1. Sensor unit (10) for the contactless actuation of an actuator element (102), in particular a flap (101) or the like of a vehicle (100), having at least one capacitive sensor element (11, 12), wherein the sensor element (11, 12) has a wire (13) which is arranged on a base element (14), characterized in that the base element (14) is at least partially made of plastic.

2. Sensor unit (10) according to claim 1, characterized in that the wire (13) is arranged at least partially on the base element (14) and/or the base element (14) has a capacitive coupling element (18) at least partially.

3. Sensor unit (10) according to claim 1 or 2, characterized in that the base element (14) only partially fixes the wire (13), wherein in particular the individual sections (14.18) of the base element (14) are separated from one another.

4. Sensor unit (10) according to one of the preceding claims, characterized in that the individual sections of the base element (14) have different holding elements (14.13) and/or fastening elements (14.6) in order to arrange the wire (13) and/or the sensor elements (11, 12) on the vehicle (100).

5. Sensor unit (10) according to one of the preceding claims, characterized in that the base element (14) substantially encloses and accommodates the wire (13), wherein in particular a fixing element (14.6) is provided for this purpose.

6. Sensor unit (10) according to one of the preceding claims, characterized in that at least one fixing element (14.6) has a slot through which the wire (13) can be inserted into the base element (14), wherein in particular the slot of the fixing element (14.6) can be closed by a holding element (14.13), in particular in the form of a single-sided or double-sided adhesive tape strip.

7. Sensor unit (10) according to one of the preceding claims, characterized in that the capacitive coupling element (18) of the base element (14) is designed as a conductive core (18), in particular in the form of a cable (18.5).

8. A security system (110) for opening and/or closing a flap (101) or the like of a vehicle (100), in particular without contact, comprising at least one sensor unit (10) according to one of the preceding claims.

9. A method for producing a sensor unit (10) for the contactless actuation of an actuator element (102), in particular a flap (101) or the like of a vehicle (100), having at least one capacitive sensor element (11, 12), in which an electrically conductive core is substantially enclosed by a base element (14), in particular electrically insulating, characterized in that a wire (13) is continuously fastened to the base element (14).

10. Method for manufacturing a sensor unit (10) according to claim 9, wherein the sensor unit (10) is manufactured according to any of the preceding claims.

Background

Such sensor units are sufficiently known from the prior art and are used, for example, in vehicles to allow contactless opening of the tailgate. Such a sensor unit is disclosed in publication DE102010049400a 1. For this purpose, capacitive sensors are used in the corresponding sensor units as proximity sensors, which expediently have electrodes of a wide area. The electrode of wide area design has the advantage that the sensor field is optimally designed so that the approach of an object, in particular in the form of a leg of a user, can be detected in the sensor by a change in capacitance. It has thus proven advantageous if the capacitive sensor has a certain width in order to improve the measurement result. DE102010038705a1 also discloses a sensor unit for contactless actuation of a tailgate of a vehicle. In this publication too, it is stated how a collision with an object located in the area of the flap can be prevented.

A sensor unit for actuating a tailgate in a vehicle is also known from publication DE102010060364a1, which sensor unit has two separate capacitive proximity sensors in order to be able to detect a movement, in particular a movement process, of the legs in accordance with a measurement technique. The sensor unit is in contact with the safety system of the vehicle, so that the authentication of the ID transmitter can also be initiated by the user via the sensor unit.

The sensors known hitherto from the prior art for such sensor units therefore have a certain width and length in order to achieve an optimized measuring range. For this purpose, flat, electrically conductive strips or films are usually used as sensors. However, since these sensors are arranged in critical areas in the vehicle, in particular on the inside of the bumper, and are subject to strong dirt, stone blows, water jets and the like, they must be mounted in a protected manner against external influences. In practice, it has been shown here that unfortunately the sensor is not sufficiently protected from damage due to splashes of water and stone blows, which results in the sensor becoming inoperable.

Disclosure of Invention

It is an object of the present invention to provide a sensor unit and a sensor system, in particular a safety system for a vehicle, such that the disadvantages of the prior art are overcome. In particular, the object of the invention is to obtain a variably usable sensor unit which can be used in very different situations, for example in different vehicle models, different vehicle installations, etc. Furthermore, it is an object of the invention, inter alia, to create a cost-effective and robust sensor unit which is also resistant to external, mechanical environmental influences.

This object is achieved according to the invention by a sensor unit having the features of independent claim 1, in particular in the characterizing portion. This object is also achieved by a security system, in particular a (passive or active) keyless entry system for a vehicle, having the features of independent claim 30. In order to achieve the object of the invention, a method for producing a sensor unit is also proposed, which method has the features of claim 31, in particular in the characterizing portion. Preferred embodiments of the invention are specified in the device and method dependent claims. The features disclosed for the sensor unit according to the invention and/or for the safety system according to the invention are also applicable here for the production method according to the invention and vice versa. Furthermore, the sensor unit according to the invention can be produced by the method according to the invention as claimed in claims 31 and 32.

The sensor unit according to the invention for the contactless actuation of an actuating element, in particular a flap or the like of a vehicle, has at least one capacitive sensor element, wherein the sensor element in turn has a wire, which is arranged on a base element. In this case, it is provided according to the invention that the base element is at least partially made of plastic.

By using plastics as a component of the base element, it is possible on the one hand to achieve: the base element can be used in critical places in the vehicle even if it is directly subjected to weather and/or splashes of water from tires or the like. The plastic here has the advantage that the plastic is very resistant to external environmental influences, such as, for example, water, uv radiation, heat and the like. The plastic as a component of the base element has the advantage, inter alia, that the plastic can be designed more or less in any desired manner, so that the base element can be designed accordingly in order to be able to be mounted on a vehicle.

Furthermore, it is conceivable within the scope of the invention for the wire to be arranged at least partially on the base element. It is thus assumed that the base element does not need to completely support the wires, but that the wires are also arranged partly without support of the base element. It is conceivable here for the base element to fix the wire only in places, wherein in particular the individual sections of the base element are arranged separately from one another. It is thus assumed that: each section of the base element is just free of material connections with respect to the respectively adjacent section of the base element. In this case, sections of the base element can be present both in the longitudinal direction and in the transverse direction of the base element. It is also conceivable for the individual segments of the base element to be equipped with connecting elements in order to be able to connect them to one another in a form-fitting and/or force-fitting manner, if desired, so that the length or width, for example, of the segments of the base element can thereby be doubled by the connection of the corresponding segments established. The connecting element can hold the individual segments of the base element together, for example, as is the case for two puzzle pieces, for example. It is also possible to provide almost dovetail-shaped connecting elements, which cooperate with dovetail-shaped recesses in adjacent sections of the base element.

It is also conceivable according to the invention for the individual sections of the base element to have different holders and/or fasteners in order to thus arrange the wires and/or the sensor elements on the vehicle (the respective holders and fasteners are described in more detail below). The retaining element serves to fix the section of the base element to the vehicle and the fastening element serves to fix the wire to the base element.

The design of the base element in sections increases the usability of the sensor unit according to the invention, since the sensor unit can be adapted particularly easily to the desired geometric design of the respective vehicle type or vehicle (for example with or without a trailer coupling and with or without a distance monitoring system, etc.). In general, the corresponding wire can be bent easily and can thus be guided along a desired contour on a vehicle, in particular on a bumper or the like. In order to achieve a fastening to the vehicle, the individual sections of the base element can be fastened to the vehicle, in particular to the bumper, at the desired points. The sensor unit can thus be adapted to the respective installation situation or use situation not only in its longitudinal direction, but also in all three directions in a simple manner. In this case, the possibility of use can be further increased by the use of different holders and/or fasteners on the respective sections of the base element, since, for example, precisely one section of the base element has an adhesive holder and the other section of the base element has a catch-type holder in order to achieve a fastening to the vehicle.

It is also conceivable within the scope of the invention for the base element to substantially enclose and accommodate the wire. Whereby the wires are more or less completely protected by the base element. As a result, the wires are also not directly exposed to the weather, since the base element is correspondingly shielded from the weather. This is of course only effective where the wires are also actually encased by the base element. In particular, the already mentioned fixing elements can be used to enclose the wires in the base element.

It is also conceivable for at least one fastening element to have a slot through which the wire can be inserted into the base element. The slit of the fastening element can be closed by a holding element, in particular in the form of a single-sided or double-sided adhesive tape strip or adhesive tape. In this case, the wire is completely embedded in the interior of the base element and cannot be removed from the base element either, since the gap through which the wire can be removed from the base element is closed by a strip of adhesive tape or adhesive tape. A particularly stable and reliable sensor unit is thereby created. This measure has the advantage, inter alia, that also water cannot penetrate through the slot-shaped fastening element, which could lead to a considerable distortion of the measurement result of the capacitive sensor element.

It is also possible within the scope of the invention for the base element to have at least one capacitive coupling element. By means of the capacitive coupling elements, the measuring range, in particular the geometric measuring range, of the respective sensor element can be correspondingly enlarged or widened. The measurement accuracy of the sensor unit according to the invention can thus also be significantly improved. In this case, it is conceivable for the capacitive coupling element of the base body to be designed in the form of a conductive core, in particular a cable. The electrically conductive core can be arranged on or in the base element parallel to the extent of the wire. If a cable is used as the conductive core of the base element, the cable may run parallel to the wires on or in the base element. In this case, a plurality of cable bundles can also be provided, which do not necessarily have to be but can be electrically connected to one another.

It is also conceivable according to the invention for the base element itself to form the capacitive coupling element, wherein in particular the base element is formed as a conductive core. As a result, the entire base element is formed as a conductive core. This feature is further described below.

According to the invention, it is conceivable for the base element to have at least one electrically conductive core. The conductive core serves to improve the measurement-technical properties of the capacitive sensor element and, if necessary, to extend the measurement range of the sensor element. For this purpose, the conductive core is capacitively coupled to the metal filaments of the base element. The wire and the conductive core thus jointly form a capacitive sensor element, whereby a desired width of the sensor element can be achieved. For this purpose, the wire itself does not need to be directly conductively connected to the conductive core. Instead, an (electrical) insulator may also be provided between the wire and the conductive core. The sensor unit according to the invention can be produced cost-effectively by means of a particularly simple design, since an automated production of the sensor unit according to the invention with a capacitive sensor element is possible. Furthermore, the existing capacitive sensor elements are particularly well protected against external mechanical influences, so that a stable and long-lasting operation of the sensor unit in harsh measurement surroundings, such as, for example, in a wet external region of the vehicle, is ensured. By means of the capacitive coupling of the wire to the conductive core, the corresponding capacitive sensor element also possesses outstanding measuring properties, which have proven to be very advantageous in tests. It is also possible that the wire can be arranged on the base element, in particular protected against external influences. The base element thus acts almost as a housing for the wires. It is also conceivable that the wire and the base element can be arranged in a further housing or a sleeve, so that the unit is reliably protected against external influences, such as, for example, moisture, salt, etc.

The sensor unit according to the invention can have at least two or more capacitive sensor elements, which are ideally connected to one another via a common plug. It is also conceivable to use a separate plug for each sensor element. Usually, they are each arranged side by side or highly offset on the vehicle, so that the course of the movement of the user can be recognized, for example, by an indicated step or by a walk by side. The sensor unit according to the invention is electrically connected to the control unit for this purpose via an existing plug. The wires of the individual sensor elements ideally project directly into the plug, so that the connection points or the transition pieces can be dispensed with. The production costs can thereby likewise be reduced. This also eliminates critical weak points in the sensor unit, since the sensor element is designed to be contactless, i.e. without electrical contact points, nor enclosed or cast contact points. In the case of the already mentioned controllers, it is also possible to integrate a plurality of sensor units and to carry out an analysis there according to measurement techniques. The controller can then transmit the measured measurement signals to the vehicle electronics or to the respective safety system. For this purpose, the controller preferably has a data bus interface, for example in the form of a CAN bus or a LIN bus. The sensor unit according to the invention can thus be integrated in a simple manner into the integrated vehicle electronics.

According to the invention, it is conceivable that the wires run substantially parallel to the longitudinal direction of the base element. This makes it possible to dispense with the winding of the wire on the base element in order to achieve a certain width of the measuring range. The wire thereby runs essentially straight on the base element and therefore particularly short wires can be used, which can also be fastened to the base element particularly simply and reliably.

Furthermore, according to the invention, it can be provided that the wire is arranged continuously (endlos) on the base element, wherein in particular both ends of the wire are arranged in particular protruding on one end of the base element. By "continuously" is understood here that the wire is not simply arranged on or in the base element, but rather only a loop or a middle section of the wire is completely arranged on the base element and the two ends of the wire are ideally connected to the plug mentioned. The functional capability of the sensor element or of the sensor unit according to the invention can thus be checked via a simple resistance measurement. Furthermore, the plug identification can also be carried out simply by the controller, since the resistance measurement directly gives an explanation for this (Aufschluss). In this way, a permanent fracture monitoring (Bruch ü berwachung) of the capacitive sensor element with a continuous wire, which is continuously fixed to the base element, can also be achieved in a simple manner. The continuous arrangement has the advantage, inter alia, that no additional electrically conductive contact points are provided on the base element, which contact points are always weak points, since these must be protected against corrosion and mechanical stress. The coherent wire thus has the major advantage that it does not possess precisely at such weak points.

Preferably, at least the conductive core of the base element or the metal filaments on the base element have a (electrical) specific volume resistance (durchgapswinderstand), which is also material-dependent and in the case of a) aluminum is less than 10⁴Omega cm and in the case of b) magnesium less than 10⁶Ω cm (DIN 50014-23/50-2 after 48 hours of storage in normal climates according to DIN IEC 60093) in order to avoid corrosion on the conductive sites as far as possible.

It is also possible within the scope of the invention for the wire to be arranged on the base element substantially in one plane. It has proven advantageous here if the imaginary plane of the wire is arranged as close as possible to and/or parallel to the conductive core, thereby improving the capacitive power of the sensor element as a whole. For this purpose, it is also advantageous for the insulation between the wire and the conductive core to have a high dielectric constant or permittivity. By using a conductive core on or in the base element, the measuring range of the capacitive sensor element is significantly improved or enlarged. The measuring range of a capacitive sensor element with a conductive matrix is increased by a multiple compared to the measuring range of a bare wire.

It is also conceivable according to the invention for the length of the section of the wire which is arranged directly on the base element to be substantially twice as long as the length of the base element. Whereby the forward and also return guidance of the wire on the end of the base element becomes evident. It is advantageous here for the wire to be guided along the entire length of the base element and to be routed approximately 180 degrees at the opposite end⁰So as to be directed back again from the other end, i.e. the second end, to the first end. In this case, the wire is arranged on the base element, in particular in a U-shape, wherein the deflection of the wire at the second end can also take place externally, i.e. not directly, on the base element.

In order to improve the measuring properties of the sensor unit according to the invention, the conductive core can be designed to be large-area. The conductive core may be arranged completely in the base element or may be arranged only on the base element. But it is important that the wire is capacitively coupled to the conductive core.

As mentioned here in this way, it is also conceivable that the conductive core forms a matrix element. This is understood to mean that the conductive core itself is the matrix element. It is advantageous here for the wire used itself to have an insulator which galvanically isolates the wire from the base element.

It is likewise conceivable for the base element to be encased or overmolded by a protective sheath, in particular an electrical insulator. In this case, the base element can also consist entirely of the conductive core. Of course, the base element itself, which consists of a non-conductive material and has a conductive core, can also be coated or encased.

In addition, it is possible within the scope of the invention for the conductive core to be flat. It is conceivable here for the conductive core to be of film-like design. It has advantageously proved to be that the core has a thickness of less than 5mm, preferably less than 2mm and particularly preferably less than 0.5 mm. The reduced thickness of the conductive core also has the advantage here that the entire sensor element becomes more flexible, since the mechanical deformation of the conductive core becomes easier as the thickness decreases.

It is also possible within the scope of the invention for the conductive core to extend over substantially the entire length and/or width of the base element. The core need not therefore be arranged completely in the base element, but can also terminate (absclie β en) with the base element at the first end or the second end of the base element. However, a particularly long and/or wide measuring range of the sensor unit according to the invention can also be achieved by the core extending over the entire length and/or the entire width of the base element. Furthermore, the production of the base element is thereby also simpler, since the base element can be produced almost as a continuous material or as a metric article (Meterware), in particular according to the (plastic) continuous casting method, in that: embedding a very long conductive core. In order to produce the sensor unit according to the invention, the basic element bundle then only has to be cut to its desired length, wherein only the electrically conductive wire is then additionally fastened, which is advantageously achieved by clamping.

In order to make it particularly simple to design the base element to be shortened to its desired length (precisely in the case of metric goods), the conductive core and/or the base element have a corresponding separation point and/or a rated breaking point or a boundary seam. The base element with the conductive core, which is produced in particular as a rice product, can thus be brought to the desired length by simple separation, for example by cutting, sawing or twisting off or tearing off. For this purpose, the conductive core can have the already mentioned separation points and/or rated breaking points. The boundary seams already mentioned can be present in the base element for this purpose. The separation and/or the rated breaking point of the core is expediently geometrically identical to the boundary seam of the base element.

Since the electrically conductive wire is continuously guided on the base body, this wire can be provided with a plug beforehand, so that the entire production of the sensor unit according to the invention can be carried out particularly simply, substantially automatically and in a few production steps. Furthermore, it is also possible to produce individually variable sensor units, since, as already mentioned, only the base element has to be shortened to the corresponding length and then a wire of the corresponding length is arranged thereon. Other individual manufacturing criteria are thus not required. Thereby enabling the desired mass production.

Furthermore, it is possible according to the invention to provide projections (buckels) on the base element, which projections are arranged in particular in the region of the parting line of the base element and/or in the region of the separation point or the rated breaking point of the core. The aforementioned projection is a material deposit and/or an accumulation of the base element, by means of which the shortened base element can be closed at the separation point. For this purpose, projections can be used which, by heating, close the separation points of the base element in a material-bonded manner in order to thereby optimally protect the conductive core against corrosion. Even in the case of an electrically conductive core made of corrosion-resistant material, it can be expedient if the separation points of the base element are closed by a material bond by means of a raised material, so that no moisture or water can accumulate in these regions in possible gaps. It is precisely moisture and water that significantly distorts the measurement results of the capacitive sensor. The projections mentioned thereby serve to close the separation points and in particular the gaps that are present in a bonded manner when the base element is broken. The projections are ideally arranged in the region of the parting seam of the base element or in the region of the separation point or the rated breaking point of the core.

Furthermore, it is conceivable according to the invention that the electrically conductive core of the base element or the base element itself is substantially surrounded by a, in particular planar, protective sheath, which is also referred to in part as a base plate. The protective sheath can simultaneously have an electrical insulator, so that it can advantageously consist of a material. If the protective sleeve is an electrical insulator, it is thereby ensured that the wire is arranged in a current-proof manner from the core of the base element.

Irrespective of the design of the base element, it can also be provided that the wire is provided with an electrical insulator at least in the region of the base element. Advantageously, standard wire may be used for the wire, which can be obtained at low cost and as a mass commodity. Here, the wire may be in accordance with the standard: FLRY or FLY. Such a wire may be a single-core wire, which may in particular have a plurality of copper strands. The ideal cross-section of the wire is about 1mm, but thinner or thicker cross-sections are also conceivable. However, the mechanical load capacity of the wire is comparatively low when the wire is thin and thus there is a risk that damage may occur when the wire is fastened to the base element. Thicker wires have the disadvantage of being costly, since a higher copper fraction is consumed. This increases the cost, but not the technical performance of the sensor element, substantially only due to the increased copper consumption. Ideally, the wire is provided with a continuous insulating layer, which is embodied as a plug up to the sensor unit.

The sensor elements used for each sensor unit can preferably be of identical design or of identical design. The production costs can thereby be further reduced, since the number of pieces per sensor element can be significantly increased. However, it is also conceivable for two or more sensor elements of different design to form one sensor unit. In this way, for example, the length of the sensor element, which is also substantially predefined by the length of the base element, can be varied. The width of the respective sensor element of a further sensor unit can also be designed differently. This does not reduce the production costs, but nevertheless achieves an improved use of the corresponding sensor unit on the vehicle.

It is also conceivable within the scope of the invention for at least one capacitive sensor element of the sensor unit to have a local shielding. In this way, the measurement range of the sensor element can be influenced in a targeted manner in order to suppress disturbances which are otherwise detected together by the sensor and which are actually outside the desired measurement range, for example. In this way, the region of the wire between the plug and the base element can be provided with a shield. It is likewise possible for the shield to be just a wire or a metal foil or a flat strip which has a different potential than the electrical (measuring) wire of the capacitive sensor element, preferably the shield is grounded or provided with a zero potential. It is of course also possible to provide two separate shielding wires on one capacitive sensor element, and it is also conceivable to use an additional shielding element in the sensor unit according to the invention, which shielding element is arranged, for example, beside or behind both capacitive sensor elements.

In order to improve the flexibility of the sensor element, it can be provided according to the invention that the conductive core is comb-shaped, in particular double comb-shaped. Comb-like is understood to be: individual teeth project, in particular perpendicularly, from an intermediate bridge, wherein the teeth are arranged parallel to one another on the intermediate bridge. Double comb is understood to be: the teeth are arranged on both sides of the intermediate bridge. In order to improve the flexibility of the comb core, it is provided that all the teeth are arranged at the same height of the intermediate bridge, so that the teeth arranged on both sides are not offset with respect to one another. In addition, additional material costs are saved by the comb-shaped design, since material-free intermediate spaces are formed precisely between the individual teeth of the comb core.

In order to design the sensor element according to the invention as corrosion-free as possible, the conductive core is made of stainless steel, copper, brass and/or an electrically conductive polymer. The materials listed above have the advantage that they are electrically conductive on the one hand and corrosion-insensitive on the other hand. If the base element is manufactured as a metric product, the end of the conductive core thus projects from the base element unprotected. The term rice goods is to be understood in the context of the present invention as long rod-shaped materials (several meters long) from which the desired length for the base element can then be produced by cutting. Stainless steel has the advantage in this respect that stainless steel is significantly less costly than brass or copper. Copper and brass have very good electrical conductivity, thereby improving the measuring ability of the sensor element. It is also conceivable for the electrically conductive core to also comprise an electrically conductive polymer, so that the entire base element can be designed to be highly flexible. All the materials listed above can be designed as a conductive core both flat and comb-like or double comb-like.

If the conductive core or the entire matrix element has a conductive polymer, the polymer may be one of the following materials:

-poly (3, 4-dioxoethylthiophene)/poly (p-styrenesulfonic acid) (PEDOT: PSS)

Polyacetylene

-polyaniline

Poly-p-phenylene (polyparaphynylen)

-polypyrrole

Polythiophenes

Such conductive polymers are characterized by intrinsic electrical conductivity. Thus, such polymers have extended pi-electron systems. A significant increase in conductivity is only achieved in the case of doped polymers. The delokalireceiver ion center in the polymer is formed by strong oxidizing or reducing agents, where the corresponding dopant forms the counter ion. In some polymers, in particular in the case of elastomers, thermoplastic elastomers or thermoplastics, electrical conductivity can also be achieved by incorporating metal powders, carbon black or graphite. In the case of rubber-like conductive polymers, the use of the sensor unit according to the invention can be improved thereby, i.e. an extreme flexibility of the sensor element is achieved. The outer contour of the base element can thereby also be varied, so that the base element has, for example, a circular or rectangular cross section and the wires are arranged therein.

In the context of the invention, it is also conceivable for a fastening element, in particular in the form of a clip, to be provided on the base element, by means of which fastening element the wire can be fastened and/or fastened to the base. Advantageously, this fixing can take place by means of a form-fit, in which, for example, a wire can be clipped or hooked by means of a predetermined fixing. In this variant, it is additionally advantageous if the already mentioned protective sleeve or base plate of the base element is formed integrally and/or materially in accordance with the fastening element. The conductive core is expediently enclosed for this purpose by a plastic injection-molded part, on which the fastening part is directly molded. As already mentioned, such a base element can be produced as a continuous casting compound in the form of a metric article. Via the existing fastening elements, the shortened base element can then be provided with the required wires, so that the base element, together with the conductive core and the wires, forms the main component of the capacitive sensor element. The wire is arranged completely or partially wrapped on the base element by means of the fixing element.

The aforementioned fastening elements can be provided individually or in sections on the base element. It is also conceivable for the fastening element to be arranged on the base element continuously over the length of the base element. The wire can thereby be arranged in a protected manner on the base element from one end of the base element to the other end of the base element, in succession, via the fastening element. The wire is deflected only at the ends of the base element and guided back in a protected manner via a second fastening element, which is in turn arranged consecutively from beginning to end on the base element. In this way, two consecutive fastening elements are arranged on the base element, in particular parallel to one another. In order to improve the measurement-technical properties of the sensor unit, the two parallel fastening elements are preferably arranged on the base element as far as possible outside (viewed over the width of the base element), as a result of which the measurement range can be widened. The fastening means itself is essentially hook-shaped, wherein an arm or neck, to which the hook or mushroom-head-shaped head of the fastening means is then connected, projects from the flat side of the protective sleeve or from the base plate of the base element. The hook or mushroom-head-shaped head is shaped in such a way that it holds the wire, in particular in a form-fitting manner, on the base element. Due to the flexibility of the fastening element, the wire can thus be clamped to the base element by the fastening element. The gap between the hook or mushroom-head-shaped head end of the fastening element relative to the base element can be designed to be narrower than the maximum thickness of the wire. In a preferred case, this gap is virtually nonexistent, so that the fastening means, via its open hooks, again contact the flat protective sleeve of the base element or the already mentioned base plate, but are not connected thereto. The gap which exists between the open end of the fastening element and the base plate of the base element, viewed over the width of the base element, can be arranged outwardly or inwardly. The fitting of the wire is particularly simple if the hook-shaped fastening elements are opened outwards. However, if the openings of the hook-shaped fastening elements are oriented inward, i.e., toward the center axis of the base element, the wires are ideally arranged in a protected manner on the base element. It is alternatively conceivable for additional locking tongues to be provided on the fastening element, by means of which locking tongues it is ensured that: the wires are no longer accessible from the fixing after fitting on the base element. It is also conceivable that the openings of the hook-shaped fastening elements are closed in a material-engaging manner after the wire has been fitted. This can be done, for example, by potting material or silicone or welding. This ensures that the wire is arranged on the base element in a completely protected manner, surrounded by the fastening element.

In order to also protect the wires, in particular the return wires, at the ends of the base element, caps can be provided which are plugged onto the ends of the base element and, if appropriate, reliably mount the wires thereunder. The caps may for example be clipped, glued or welded to the respective ends of the base element. It is advantageous, in particular when the base element is produced as a metric or batch product, if at least the separated ends of the base element are closed with caps. The cap can also be used to guide the wire, in particular when the cap does not close the end of the base element where the wire turns. In this way, a tension-releasing element for the wire can be provided on the cap in order to mechanically fix the wire by its two ends to the cap or to the base element. The sensor element according to the invention can thus be produced in a particularly cost-effective manner overall. Furthermore, the cap can also protect the separate ends of the base element, in particular the conductive core of the base element, from environmental influences and corrosion phenomena. At the same time, the cap can also be used to fix the sensor element to the vehicle in that way: the cap has corresponding fasteners. However, if the entire base element with the provided wires is once again encased, for example by a hose, or provided in a housing, the additional cap can be dispensed with.

As already mentioned above, the fixing elements on the base element serve to guide and support the wire on the base element. For this purpose, the fastening element can have a neck and a mushroom-head-shaped end in order to be configured hook-shaped. It is also advantageous if the wire is longitudinally displaceable in the interior of the guide device by means of a fixing on the base element. The flexibility of the entire sensor element can thereby be additionally improved, wherein mechanical tensile and/or compressive stresses in the wire are avoided.

In the context of the present invention, it is particularly advantageous if the sensor element with its base element and the wire is designed to be flexible overall, in particular in the longitudinal direction. In this way, the base element can be adapted in a simple manner, for example, to different inner contours of a bumper in a vehicle. The base element is thereby adapted to the corresponding shape of the bumper or the rocker (kerschwell) or the like during assembly. This also makes it possible to guide the sensor element via corners and edges on the vehicle, so that for example the measuring region of the sensor element can also be bent 90⁰If, for example, the lateral region to the rear region of the vehicle is to be measured. In order to achieve the required flexibility, the base element itself can be constructed from a flexible base material. This makes it possible to dispense with the base elementIn particular prefabricated shapes, so that additional costs can be saved. The base element can have a base plate for this purpose, from which base plate in particular a fastening element for fastening the wire projects.

Furthermore, it is conceivable according to the invention that at least one cover element is provided on the base element, whereby the base element and the wire can be partially covered. The cover element may also completely cover the base element, so that the wire is reliably arranged under the cover element and protected against direct mechanical influences. Preferably, the cover element can be connected to the base element, in particular to the protective sleeve or the base plate, in a bonded manner or via a hinge or the like. After the assembly of the wires, the cover element can then be closed, so that it serves as an additional protective element for the wires located therebelow. The cover element is ideally hinged at least on one side to the base element, in particular to the base plate, via a film hinge. The cover element can also be closed off from the base element by means of a clip connection and then the cover element can be closed off from the other side of the cover element. The corresponding base element itself thus forms a housing in which the wound wire is reliably arranged.

Furthermore, it is conceivable within the scope of the invention that the entire base element can be arranged inside a housing or a sleeve (for example in the form of a hose) and thus be protected against external influences.

It is also conceivable for the base element to be designed as an injection-molded element made of a stable plastic. In this case, at least one dividing seam with at least one connecting bridge can be provided over the length of the base element in order to achieve flexibility of the base element, in particular in the longitudinal direction. Of course, it is also possible to provide a plurality of dividing slits over the length of the base element, whereby the flexibility is further improved. By using a parting line, it is possible to produce the injection-molded element from only one material which is sufficiently stable for guiding and holding the wound wire on the one hand, and which is flexible such that the base element or the sensor element is adapted to the predetermined shape, for example by the inner contour of the vehicle bumper. Ideally, only one intermediate bridge of the conductive core is provided in the region of the dividing seam.

In order to provide a particularly simple and reliable arrangement of the individual sensor elements in the sensor unit on the vehicle, it can be provided that a holder is provided on the base element, by means of which the sensor can be fixed on the vehicle. The mentioned retaining means can be materially bonded and/or fixed to the vehicle in a non-positive and/or positive manner. Ideally, the holder is arranged directly on the base plate or on the cover element or is injected thereon. As the holder, a flat plate can be used, whereby for example the sensor element can be glued or can be welded to the vehicle. A tongue-shaped or arrow-shaped or projection-shaped latching element can also be provided as a holder, by means of which the base element can be fixed to the vehicle by latching. Depending on the configuration of the holder, the sensor element can be irreversibly or reversibly fixed on the vehicle. It is also conceivable that the base element can be fastened to the vehicle via external fastening means, such as, for example, clips (spans) or clips or screws and rivets. Thus, for example, a housing-shaped clip can be used to fasten the base element to the vehicle, which clip at the same time partially or wholly forms a housing for the base element. Combined holders are also conceivable within the scope of the invention.

The invention is also directed to a safety system according to claim 30 for opening and/or closing a flap or the like of a vehicle, in particular without contact. At least one sensor unit according to the invention is used here (i.e. according to claims 1 to 29). As already mentioned, the individual sensor units according to the invention are connected to the safety system of the vehicle via one or more controllers. The controller can also be integrated in the safety system.

The invention is also directed to a method for producing a sensor unit according to the preamble of claim 31. According to the invention, the wire is continuously fixed to the base element. But the base element itself must be manufactured before the wires can be fixed to the base element. This can preferably be produced as a plastic injection-molded part in the form of a metric commercial product. In this case, the electrically conductive core is directly embedded in the base element or the base element itself forms the core, as long as it has an electrically conductive polymer. The fastening means provided for fastening the base element can be produced at the same time as the other aforementioned elements of the base element, or the fastening means can be connected to the base element in a materially bonded manner, such as, for example, a cover element. Now after the base element has been manufactured with its core as a metric article, it has to be shortened to the desired length, preferably by (laser) cutting, snapping, turning or sawing. The base element now has the correct length. The wire is then fixed to the base element in the following manner: the wire is clamped to the base element by means of a fastening element or pressed or pulled into the fastening element. The wire is at least partially or completely enclosed on the base element by the fastening element. As also mentioned above, it is also conceivable for the open gap of the hook-shaped fastening element to be closed in a material-bonded manner, for example by a protective sleeve or a heat-shrinkable tube. If a projection is present on the base element, the separation of the ends of the base element can thereby be closed before or after the assembly of the wire. Additionally, at least one end or both ends of the base element may be provided with a cap. The finished base element can now be assembled as long as the wires have been provided with the required plugs.

Drawings

The features of the invention, of the description and of the claims, of the device according to the invention and of the method according to the invention are essential for the invention both individually and in very different combinations. Further measures which improve the invention are shown in detail below together with the description of preferred embodiments of the invention with the aid of the drawing. In the drawings:

fig. 1 is a plan view of a sensor unit according to the invention with two capacitive sensor elements;

FIG. 1a shows a section A-A of the sensor unit according to the invention in FIG. 1 in the plug region;

FIG. 1B shows a section B-B of a first sensor element of the sensor unit according to the invention in FIG. 1;

FIG. 2 is a schematic top view of a section of a sensor element of the sensor unit according to the invention;

FIG. 2a is a section A-A of the sensor element of the sensor unit according to the invention of FIG. 2;

FIG. 2B is a section B-B in FIG. 2a in the conductive core region of the sensor element of the sensor unit according to the invention in FIGS. 2a and 2;

FIG. 3 is a similar section A-A as in FIG. 2a of an alternative sensor element of the sensor unit according to the invention as in FIG. 2;

fig. 4a shows a section a-a of an alternative sensor element, similar to fig. 2a and 3, of a sensor unit according to the invention;

FIG. 4B is a section B-B through the sensor element of the sensor unit according to the invention in FIG. 4 a;

FIG. 5 is a partial top view of a sensor unit according to the invention with two sensor elements;

FIG. 5a shows a section A-A through the sensor element of the sensor unit according to the invention in FIG. 5;

FIG. 6 shows a section A-A of a further alternatively embodied sensor element of a sensor unit according to the invention;

fig. 7 is a side view of a vehicle with a safety system according to the invention and at least one sensor unit according to the invention;

FIG. 8a is a similar section B-B of an additional sensor element similar to that of FIG. 1B, wherein the core has a separation;

FIG. 8B is a similar section B-B of one other sensor element of FIG. 8a, but with the core having a nominal fracture site;

FIG. 9 is a cross-section A-A of an alternatively configured sensor element with protrusions for closing off discrete portions of the base element;

FIG. 10a is a cross-section A-A of an alternatively configured sensor element with a protrusion as a material accumulation;

FIG. 10B is a section B-B of the sensor element of FIG. 10a with the cap shown;

FIG. 11 is a schematic top view of the initial end of the base member with the cap with the release tension member;

FIGS. 12a to 16b show a section A-A of an alternatively constructed sensor element with different base elements of different cross-sections;

FIG. 17 is a section A-A of an alternative sensor element with a rectangular cross-section and a closed fixture for the wire;

FIGS. 18a to 18c show a section A-A of an additional, optionally embodied sensor element with differently embodied base elements of different cross-sections;

FIGS. 19a and 19b are plan views of an alternatively embodied sensor element with a segmented base element; and

fig. 20 is a schematic plan view of a sensor element mounted on a bumper of a vehicle.

Detailed Description

The same reference numerals are used for the same technical features in the figures even for different embodiments, whereby the combination of features of the embodiments becomes clear.

Fig. 1 shows a plan view of a first exemplary embodiment of a sensor unit 10 according to the invention. The sensor unit 10 according to the invention can be clearly seen here in its entirety with its two sensor units 11, 12. As already mentioned, it is also conceivable for the sensor unit 10 to also have other sensor elements 11, 12 of identical or different design. In or on each sensor element 11, 12, a continuous wire 13 is provided, which has its start and its end in the plug 17. The respective wire 13 thereby runs continuously on the base element 14 of the sensor element 11 or 12 and essentially parallel to the longitudinal direction 15. The exemplary embodiment in fig. 1, 1a and 1b shows a preferred variant, since the base element 14 used here protects the existing wire 13 more or less completely by means of the fastening elements 14.6 provided.

As can also be seen from fig. 1, retaining elements 14.13 are provided on the side faces of the base elements 14 of the two sensor elements 11, 12, which retaining elements are rectangular in configuration and are distributed in sections over the length of the respective base element 14. These holding parts 14.13 can be provided with adhesive tape, so that the sensor unit 10 according to the invention can be fixed, in particular glued, to the vehicle 100. The holding parts 14.13 can also be used to fix the sensor unit 10 to the vehicle 100 in a form-fitting and/or force-fitting manner, in particular to the inner side of a bumper or side sill.

As can also be seen from fig. 1, the wire 13 of each sensor element 11, 12 extends from the plug 17 to the respective base element 14 and is fixed there to the base element 14 parallel to the longitudinal axis 14.15 and extends from a first end of the base element 14 (in the vicinity of the plug 17) to a second end of the base element 14 (see reference numeral 14.15, second end of the base element 14). At the second end, the wire 13 turns generally 180 degrees⁰And again extends parallel to the longitudinal axis 14.15 from the second end of the base element 14 back to the first end in order then to terminate again in the plug 17. In the region of the base element 14, the wires 13 run substantially parallel and are held for this purpose by means of the fastening elements 14.6 on the base element 14, as can be seen further from fig. 1 b. This continuous (endless) arrangement of the wires 13 on the base element 14 has the advantages already mentioned in detail. Additionally, the wire 13 can be provided with a shield 13.5 (see fig. 5) between the plug 17 and the base element 14.

Fig. 1B shows a section B-B through the first sensor element 11 of the sensor unit 10 according to the invention from fig. 1. As can be seen well, the wires 13 are each held in the outer region of the base element 14 by a fastening element 14.6 on the base element 14. The base element 14 has a base plate 14.1 which serves as a protective sleeve 14.1 for the conductive core 18. The base plate 14.1 or the protective sleeve 14.1 also serves as an electrical insulator for the conductive core 18, which in this case is only capacitively coupled to the wire 13. The wire 13 is fastened to the base element 14 in a form-fitting and optionally force-fitting manner by means of two fastening elements 14.6. As can be seen best in fig. 1b, two fastening elements 14.6 are arranged on the base element 14 on the edge side. At the edge side is understood as: these fastening elements utilize almost the entire width 14.11 of the base element 14 and are therefore spaced as far as possible from the longitudinal axis 14.15. The fastening element 14.6 is itself designed in the form of a hook and has an arm (stem) 14.6a, to which a hook 14.6b is then connected toward the open end. The open end of the fixing element 14.6 has only a small clearance with respect to the base plate 14.1. In the situation in fig. 1b, the two fixing elements 14.6 open out. It is also conceivable for the corresponding recess of the fastening part 14.6 to be directed inwardly, i.e. toward the longitudinal axis 14.15. In the central region of the base element (in the region of the longitudinal axis 14.15), a rib 14.10 is provided, which protrudes more or less perpendicularly from the base plate 14.1 and is formed in accordance with the base plate 14.1 and/or in material accordance therewith. The ribs 14.10 can be used to better manipulate the base element 14, for example, in order to hold and then press the base element 14 against a desired surface of the vehicle 100 when the sensor unit 10 is fastened.

As can be further seen from fig. 1b, the conductive core 18 has a width which is approximately the same as the width 14.11 of the base element 14. But only at both edge sides, the conductive core 18 is also enclosed by the base element 14. On the opposite side of the projecting rib 14.10, a flat holding part 14.13, which may consist, for example, of a double-sided adhesive tape, is arranged on the base plate 14.1. It can also be seen well that the wire 13 has an insulator 13.1 which surrounds the core wire 13.2. The core wire 13.2 is the actual electrically conductive element of the wire 13. The core 13.2 can be a multi-wire core or a single-wire core. However, as is clear from fig. 1b, the core wire 13.2 is not electrically conductively connected to the conductive core 18. It is clear from this that the wire 13 is only capacitively coupled to the conductive core 18. As can also be seen well from fig. 1b, the entire sensor element 11, 12 is of flat design and therefore has a comparatively small overall height 14.16.

Fig. 1a shows a section a-a in the region of the plug 17 in fig. 1. The two lower contacts 17.1 are used here for electrically contacting the first sensor element 11. For this purpose, the wire 13 of the first sensor element 11 is guided with its first end 13.3 out of the plug 17 and ends with its second end 13.4 back in the plug 17. In the center of the plug 17, the contact 17.3 can be used, for example, for a shield 13.5 of the wire 13 for one or both sensor elements 11, 12. The two upper contacts 17.2 of the plug 17 are provided for the second sensor element 12. The plug 17 itself has a labyrinth seal, so that a watertight connection can be achieved between the plug 17 and a corresponding connection socket in the vehicle 100. In addition, the plug 17 is equipped with a latching fastener, so that the plug 17 can be latched positively with the connection socket and cannot be loosened by vibration.

Fig. 2 shows a partial plan view of a part of the sensor unit 10 according to the invention (i.e. strictly speaking the first sensor element 11). Here, the section a-a is indicated, which is shown in detail in fig. 2 a. As can be seen best in fig. 2, the two fastening elements 14.6 extend over the entire length 14.12 of the sensor element 11 or of the corresponding base element 14.

A similar cross section as in fig. 1b is shown in fig. 2 a. The conductive core 18 is in turn surrounded by a protective sleeve 14.1 of the base element 14, which is also formed as a base plate 14.1. Two fastening elements 14.6 are formed thereon, which hold the wire 13 on the base element 14 in a form-fitting manner. Also in this case, the two fastening elements 14.6 are hook-shaped and project from the base plate 14.1 in order to receive the wire 13 in a wrapped manner. In fig. 2a is also indicated a section B-B, which is shown in detail in fig. 2B.

As can be seen in fig. 2b in cross section, the conductive core 18 is comb-shaped, a double comb shape being used here. The conductive core 18 has an intermediate bridge 18.1, which is arranged approximately in the region of the longitudinal axis 14.15. From this intermediate bridge 18.1, the individual teeth 18.2 project and are on both sides, wherein intermediate spaces 18.3 are provided between the individual teeth 18.2. In the present case, the teeth 18.2 on both sides of the intermediate bridge 18.1 are each arranged at the same height, so that no offset is formed between the teeth 18.2. This improves the flexibility of the entire base element 14 in the direction of the longitudinal axis 14.15. The sensor elements 11, 12 can thereby be adapted particularly well to the predetermined shape on the vehicle 100. In fig. 2b it is shown that the teeth 18.2 are wider compared to the corresponding intermediate gaps 18.3 between the teeth 18.2. However, the width relationship can also be reversed, so that the teeth 18.2 are formed to be significantly narrower than the intermediate spaces 18.3 between the individual teeth 18.2. This also saves material for the conductive core 18 and improves the flexibility of the base element 14.

Fig. 3 shows a similar section a-a in fig. 2 of a further sensor unit 10 according to the invention, in which the base element 14 is shown without the wire 13. The base element 14 is basically distinguished by the applied holders 14.13. The retaining element is produced in one piece and material-matched fashion with the base plate 14.1 of the base element 14 and has an arrow-shaped tip, so that the base element 14 can be fixed in a form-fitting and/or force-fitting manner to a mating retaining element on the vehicle 100. For this purpose, it merely has to be pressed into the mating holder, for which purpose the holding rib 14.10 can be reused. By means of the resulting pressing force, the base element 14 automatically latches or clips into the resilient projections of the mating holder, which projections interact positively with the arrowhead-shaped tip of the holder 14.13. It is also clear from fig. 3 that two fixing elements 14.6 are present. These fastening elements 14.6 are likewise of hook-shaped design, wherein first of all the arms 14.6a project in particular perpendicularly from the base plate 14.1. To this arm or neck 14.6a, a hook 14.6b or mushroom-head-shaped head of the fastening element 14.6 is connected. The two fastening elements 14.6 are located over the entire length 14.12 of the base element 14. The two fixing elements 14.6 utilize almost the entire width 14.11 of the base element in order to promote good capacitive coupling of the metal wire 13 with the conductive core 18 of the base element 14. The conductive core 18 may be designed as a conductive film or sheet. Preferred materials for the conductive core 18 have been discussed in detail above.

In fig. 3, the arrow-shaped holding element 14.13 can be formed continuously, i.e. over the entire length 14.12 of the base element 14, or, however, only in sections or in points. In this way, after a certain distance, a respective holding element 14.13, which is designed in a point-like manner, is arranged on the base plate 14.1 of the base element 14 in order to fix the base plate to the vehicle 100.

Fig. 4a shows a further section a-a, similar to fig. 2a and 3. Basically, the base element 14 differs in the design of the holder 14.13. In this case, a U-shaped holding element 14.13 is used, which is in turn arranged on the side of the base plate 14.1 opposite the longitudinal ribs 14.10 in order to fix the base element 14. In this case, a barb-shaped latching means is provided on the parallel legs of the U-shaped holder 14.13 in order to thereby latch the base element 14 positively and/or non-positively with the vehicle 100 or a corresponding mating holder. Additionally, in addition to the holder 14.13 shown in fig. 3 and 4a, adhesive tapes can also be provided on the same side of the holder 14.13. In order thereby also to fix the base element 14 in a material-bonding manner. Section B-B of fig. 4a is shown in fig. 4B in cross-section. As can be seen well in fig. 4b, the double comb-shaped conductive core 18 is arranged in the flat protective sleeve 14.1 of the base element 14. But here the comb structure of the conductive core 18 has a larger intermediate space 18.3, which serves as a dividing slit 14.7 for the base element 14. However, this base element 14 is formed continuously, and the intermediate bridges 18.1 of the conductive core 18 also serve as connecting bridges 14.8 in the region of the dividing seams 14.7. As can be seen in fig. 1b, however, the intermediate bridges 18.1 are also enclosed by the protective sleeve or base plate 14.1 of the base element 14 in the region of the connecting bridges 14.8. This allows a very high flexibility of the base element 14 to be achieved, but the capacitance measuring capability of the sensor elements 11, 12 is not significantly affected.

Fig. 5 shows an enlarged detail view of the optionally embodied sensor unit 10 according to the invention from fig. 1. Here, a cover element 14.4 for the base element 14 is used in principle. The first three cover elements 14.4 of each base element 14 of the two sensor elements 11, 12 are shown here. As can be seen well in the enlarged view, the individual portions of the base element 14 with the respective cover element 14.4 are separated by a dividing seam 14.7, wherein the individual regions of the base element 14 are connected to one another in a bonded manner via connecting bridges 14.8 (see also fig. 4 b). In this region, the connecting bridges 14.8 run diagonally through the dividing seams 14.7 and connect the individual segments of the sensor elements 11, 12. As can also be seen well in fig. 5, a respective bending protection 14.14 is provided at a first end of the base element 14 for the two cables 13 of the sensor elements 11, 12. A shield 13.5 can also extend in each case within the bent-over protection 14.14, as indicated by the dashed lines. The task of the shield is to avoid electromagnetic interference that may lead to negative measurement results. In fig. 5, the respective cover element 14.4 is closed on the base element 14, so that the wires 13 lying thereunder are mounted in a protected manner. The fixing of the wire 13 is again via the fixing 14.6, which in this case can also be designed only in points or in sections (see, for example, fig. 6).

In fig. 5a cross section a-a of the first sensor element 11 or 12 is shown. It is particularly emphasized that the conductive core 18 is composed of individual regions, which are arranged in the base plate 14.1. These individual segments can be connected to one another in an electrically conductive manner and form the entire core 18. It is also conceivable, from the point of view of fig. 5a, for the upper and lower regions to be formed as shielding elements 16 in order to thereby orient the measuring field of the capacitive sensor. Thus, in this case only the central section forms the conductive core 18. As can also be seen from fig. 5a, the cover element 14.4 is connected to the remaining base element 14 via a hinge 14.3. The hinge is in the present exemplary embodiment designed as a film hinge. In order to close the base element 14 with the cover element 14.4, a latching means 14.5 is additionally provided, so that the cover element 14.4 is held in the closed position on the base element 14 by the latching means 14.5 in a form-fitting manner.

As can be seen in fig. 5a, the base element 14 likewise has a base plate 14.1, on which the respective fastening means 14.6 are arranged in order to hold the wires 13. These fastening elements 14.6 are connected to the base plate 14.1 in a bonded manner and have a neck 14.6a which merges into a mushroom-head-shaped or cap-shaped end 14.6 b. The wire 13 is pressed against the holding part 14.6 by this end 14.6b, so that the wire is more or less arranged in a plane 14.2 with a constant parallel distance to the core 18.

Ideally, the sensor unit 10 is arranged on the vehicle in such a way that the mechanical influence acts not from behind on the base plate 14.1 of the base element 14 but from the front on the cover element 14.4. In this way, the functionally important wires 13 are arranged in a protected manner inside the base element 14, by means of which the measuring function of the sensor unit 10 is ensured.

In fig. 6a further base element 14 is shown in cross section (similar to section a-a in fig. 2). Here again, two edge-side fastening elements 14.6 are well visible, which serve to fasten the wire 13. The two fastening elements 14.6 also have a neck 14.6a, which is connected to the base plate 14.1 in a materially bonded manner. The open end of the retaining part 14.6 likewise terminates in an end 14.6b in the shape of a mushroom head or cap. In this sectional view, too, a recess 14.9 can be seen, which is advantageous from a manufacturing point of view.

The main difference between the exemplary embodiment in fig. 1 to 4 and the exemplary embodiment in fig. 5 and 6 is that the wire 13 rests only on the fastening means 14.6 of the base element 14 without being clamped or clipped in. However, the wire 13 cannot leave its position in the base element 14 by means of an additional cover element 14.4 or an additional hose in which the base element 14 can be arranged.

Fig. 7 shows a vehicle 100 with a safety system 110 according to the invention, a sensor unit 10 according to the invention and exemplary sensor elements 11 and 12. In order to be able to open the rear flap 101 without contact, an actuator 102 in the form of an electromechanical lock is provided, which can be actuated without contact by the sensor unit 10. The servo drive 102 can be actuated if the correct control signal has been recognized by the two sensor elements 11 and 12 or has been detected by the corresponding controller.

Fig. 8a shows a section B-B of a further sensor element 11, 12. The sensor element 11 is here constructed analogously to the sensor element 11 in fig. 4 b. However, the conductive core 18 is along the longitudinal sidesInterrupted and having a separation point 18.4 in the base element 14. As can be seen in fig. 8aIn that case, the separation point 18.4 is located in the region of the boundary seam 14.7 of the base element 14. The base element 14 can be easily separated (broken) at the separation point 18.4 or the dividing seam 14.7, precisely when the base element 14 and the integrated core 18 are produced as a metric or mass product. In the case of the design of the sensor element 11, it is also advantageous that the separation point does not have to be protected further, since the core 18 remains in the base element 14 in the region of the separation point 18.4 in a corrosion-protected manner.

In the other fig. 8B, an additional section B-B of the similar sensor elements 11, 12 of fig. 4B and 8a is shown. However, the separation point 18.4 of the core 18 is replaced by two predetermined breaking points 18.4. The two predetermined breaking points 18.4 can consist of a constriction or a slot or a perforation in the core 18. By means of the predetermined breaking point 18.4 of the core 18, which is advantageously located in the region of the dividing seam 14.7 of the base element 14, it is possible to easily break the base element 14 in this region. In the design configuration of the sensor elements 11, 12 depicted in fig. 8b, it is advantageous if the conductive core 18 is continuously electrically connected over its longitudinal extension.

In fig. 9a section a-a of a similar sensor element 11 in fig. 6 is shown. Here, projections 14.17 are provided on the surface of the base element 14, in particular on the surface of the base plate 14.1. The projections 14.17 serve as material accumulation in order to be able to close the separation point of the base element 14 in a bonded manner after the disconnection. Here, the sealing may be performed by heat generation in a manner of: the projections 14.17 are melted and the hot material is applied to the separation site.

Fig. 10a also shows a section a-a of a further sensor element 11, which is similar to sensor element 11 in fig. 2. The projections 14.17 already mentioned above have also been used here. Fig. 10B shows a section B-B of the sensor element 11 from fig. 10 a. The projections 14.17, which are arranged on the base element 14 above the base plate 14.1, are indicated here by dashed lines. A cap 19 is also shown in dashed lines, which cap surrounds the broken end of the base element 14 and additionally protects the separation region of the base element 14 against external influences.

Fig. 11 shows a plan view of the beginning of the base element 14, wherein the corresponding end of the base element 14 is closed with a cap 19. The cap 19 serves simultaneously to receive and hold the wire 13 and has a release tension element 19.1. The cap 19 thus protects not only the end of the base element 14 against external environmental influences, but also the wire 13 against mechanical loads in this region. The cap 19 may be clipped, welded, glued to the base element 14. The cap 19 can also be used to securely receive the turned wire 13 on the other end of the base element 14.

Fig. 12a to 16b show different cross sections a-a of further variants of the sensor elements 11, 12 according to the invention. In fig. 12a to 14a, the wires 13 each extend through a self-closing cross section of the base element 14. In this case, the respective base element 14 is formed tubular with a circular cross section or a rectangular cross section or an oval cross section. In fig. 12b to 14b and 15a to 16b, the respective base element 14 has a fastening element 14.6, which is described above in multiple detail, in order to fasten the wire 13 to the base element 14. The special feature of the fixing element 14.6 shown in fig. 12b, 13b, 14b is that the fixing element grips the wire while being guided back and forth, so that only one fixing element 14.6 is required for the wire 13 guided back and forth. In the embodiment of fig. 12a to 16b, the conductive cores 18 may each form a complete matrix element 14. This is possible, for example, when using a conductive polymer for the conductive core 18, as already described. Purely alternatively conceivable and shown in fig. 13b, 14b and 16a is the presence of at least one additional or alternative conductive core 18. In fig. 15b and 16b, the base element 14, which is formed entirely from the conductive core 18, is enclosed by an electrically insulating protective sheath 14.1 or a heat-shrinkable tube 14.1. The production of the sensor elements 11, 12 according to the invention is particularly simple in the exemplary embodiment shown in fig. 12b, 13b, 14b, 15a, 15b, 16a and 16b, since the wire 13 only has to be pressed into the respective fastening element 14.6. In this fastening element 14.6, the wire 13 is held in a straight line on the base element 14. This makes it possible to produce the base element 14 or the respective sensor element 11, 12 particularly easily. In fig. 15a, 15b, 16a and 16b, a holding element 14.6 is provided for the forward and backward guiding of the wire 13, into which the wire 13 must be pressed accordingly.

The exemplary embodiments of the sensor elements 11, 12 shown in fig. 12a to 16b have the advantage that they are highly flexible and can therefore be fixed to a motor vehicle in a particularly simple manner and method and can be produced particularly easily. This is particularly simple in the case of a base element 14 which is composed primarily of a conductive core 18 which in turn comprises a material composed of a conductive polymer.

Fig. 13b additionally shows the holder 14.13 as a double-sided adhesive or adhesive tape strip. By fixing the holding element 14.13 to the underside of the base element 14 and simultaneously closing the slot of the fixing element 14.6, the wire 13 can be inserted into the base element 14 through the slot in a simple manner. As a result, the wire 13 is arranged in a form-fitting manner and reliably inside the base element 14, similar to the exemplary embodiment in fig. 13a, and can be removed therefrom without problems. In addition, the illustrated holder 14.13 also closes the fastening element 14.6 or the cavity formed thereby, so that no moisture can penetrate, which could lead to a falsification of the measurement result of the sensor element 11.

It follows from the figures listed above that many combinations of the features shown are possible. Thus, the cross-section of the base member 14 is not limited to the cross-sectional shape shown. It is also possible that any of the embodiments shown is wrapped by an additional protective sheath 14.1. The protective sleeve 14.1 can also consist of a heat-shrinkable hose or other coating.

Fig. 17 shows a further section a-a of a sensor element 11 or 12 according to the invention. Here, the cross section is substantially rectangular and has two circular voids for the wires 13. In order to be able to insert the wire 13 into the respective base element 14 in a simple manner, two slots are provided for two fixing elements 14.6 which are circular in cross section. In order to simplify the insertion or insertion of the wire 13, the slots are designed in the form of wedges, the wedge tips of which are oriented toward the center of the respective round fixing element 14.6. After the wire 13 has been introduced or pressed through the two slits into the two fastening elements 14.6, these slits can now be closed by a strip of adhesive tape which simultaneously serves as a holder 14.13 for the base element 14 or the sensor element 11 or 12.

In addition, it is to be mentioned with respect to the base element 14 in fig. 17 that it can also be provided only partially on the wire 13 for the purpose of fixing it. A dividing slit 14.7, for example wedge-shaped or otherwise, may also be present in the base element 14 in order to improve the flexibility of the base element in each arbitrary direction. Since capacitive coupling element 18 or conductive core 18 is not illustrated in fig. 17, base element 14 serves as a coupling element. The base element 14 itself thus comprises an electrically conductive material, in particular in the form of an electrically conductive plastic or polymer.

Fig. 18a to 18c show further sections a-a of possible design configurations of the sensor element 11 or 12. In all three exemplary embodiments, the circularly embodied fastening means 14.6 for the wire 13 are closed by corresponding holding means 14.13, which are preferably embodied as adhesive tape strips or adhesive tapes. Since the fastening element 14.6 is of almost tubular design, the flexibility and deformability of the base element 14 in any movement axis is further increased. In order to achieve an optimized fastening surface for the base element 14, a particularly wide holder 14.13 with an optimized adhesive surface is provided in fig. 18 a. Additionally, in all of fig. 18, a capacitive coupling element 18 in the form of a conductive core 18 is embedded in the base element 14. Instead of core 18, the entire base element 14 can also be used as a capacitive coupling element 18/core 18.

In fig. 18b, at a central level of the wire 13, a connecting bridge of the base element 14 is provided, in which connecting bridge the electrically conductive core 18 is also provided. This design configuration is particularly flexible if the conductive core 18 is also composed of a conductive polymer, as in the variant of fig. 18 c. This variant differs from the one in fig. 18b only in that instead of using a conductive core 18 with a square cross section, a cable or wire 18.5 is used. The cable or the conductor 18.5 can be injected or molded together and form the conductive core 18 at the same time as the base element 14 is manufactured. A particularly cost-effective and highly flexible variant of the sensor unit 10 according to the invention can thereby be achieved.

Fig. 19a and 19b show a further embodiment of a sensor element 11 or 12 according to the invention. In both variants, a base element 14 is used, which is arranged in sections and which serves to fix the wire 13. As is shown, for example, in fig. 19a in a section 14.18 of the base element 14 close to the plug 17, the base element 14 can be divided not only over its length but also over its width. Additionally, the base element can be provided with connecting elements 14.19, so that the individual segments 14.18 of the base element 14 are designed to be connectable to one another. In the present example, a dovetail-shaped connecting element 14.19 is used. Fig. 19a also shows that different holding elements 14.13 can be used for each section 14.18 of the base element 14. In this way, a large-area holder 14.13 is provided as an adhesive strip in the first section 14.18 (viewed from the left). While in the adjacent section 14.18, a retaining element 14.13 is used which is designed in the form of a snap-in or tongue-shaped element.

Fig. 19b shows that any desired shape of the sensor element 11 or 12 can be achieved by using a segmented base element 14. In this way, a section 14.18 of the base element can even imitate the curvature or curve of the wire 13, so that the wire 13 can also be fixed with the vehicle 100 in this region.

Fig. 20 shows a purely schematic top view of a bumper 103 of the vehicle 100. In this illustration, it is to be shown how the base element 14, which is arranged in segments, follows the inner contour of the bumper 103. In this case, for example, a reinforcement 104 is provided on the inside in the region of the trailer coupling 105, to which reinforcement the sensor unit according to the invention with the first sensor element 11 or the second sensor element 12 should still be able to be fastened. However, the respective sensor element 11 or 12 can be adapted to the inner contour of the bumper 103 without problems by the segmented base element 14.

It is to be mentioned here that the sensor unit 10 according to the invention can of course also be used for opening a side door or an engine compartment cover or a tank flap or the like. Instead of the sensor element 11 shown, the sensor element 12 can also be used and vice versa. Any combination of different embodiments of the sensor elements 11 and 12 in the sensor unit 10 can also be realized.

List of reference numerals

10 sensor unit

11 first sensor element

12 second sensor element

13 wire

13.1 insulators

13.2 core wire

13.3 first end portion

13.4 second end

13.5 Shielding body

14 base element

14.1 base/protective cover

14.2 plane

14.3 hinge, film hinge

14.4 cover element

14.5 latch

14.6 fixing part, clip for 13

14.6a arm/neck

14.6b hook/mushroom head-like head

14.7 parting line

14.8 connecting bridge

14.9 voids

14.10 ribs

14.11 width

14.12 length

14.13 holder for 100

14.14 bend protection part

14.15 longitudinal axis

Height of 14.16

14.17 bulge, Material accumulation

14.1814 section

14.19 connecting element for 14.18

15 longitudinal direction

16 shield element

17 plug

17.111 contact point

17.212 contact point

17.313.5 contact point

18 core

18.1 intermediate bridge

18.2 teeth

18.3 intermediate space

18.4 rated fracture site

18.5 Cable/wire

19 cap cover

19.1 releasing the tension member

100 vehicle

101 flip cover or the like

102 actuator

103 bumper

104 reinforcing part

105 trailer adapter

110 security system