1. A locking device (12) intended to detachably fix a panel (18) to a structure (14), comprising:

-a holder (30) fixable to the panel;

-a locking head (32, 132) hinged to the bracket, rotating about a first axis (52);

-a pusher (34) hinged to the bracket, rotating about a second axis (74) parallel to the first axis;

-a torsion spring (40) comprising at least one coil (90) and a first arm (86) and a second arm (88) connected thereto, the ends of the two arms being connected to the locking head and the push rod, respectively;

the locking device can move between a closed state and an open state, and in the closed state, the lock head is connected with the push rod; in the opening state, the lock head and the push rod do not need to be connected; the first stress of the torsion spring in the closed state is larger than the second stress of the torsion spring in the open state;

the locking device is characterized in that:

-the torsion spring has at least one coil (90) centerline located on the second axis (74); -the locking means comprise a displacement surface (42) associated with the end of the first arm (86); and

in the closed configuration and in the open configuration of the locking device, the locking head has a displacement trajectory (58, 158) in contact with the displacement surface (42): the displacement surface will move along a displacement trajectory when the locking device is moved between the closed configuration and the open configuration.

2. The locking device according to claim 1, wherein the displacement surface comprises a roller (42) hinged to the end of the first arm (86) on a third axis (98) parallel to the second axis.

3. A locking device according to claim 1 or 2, wherein the displacement path comprises a first end (60) and a second end (62), the second end being contiguous with the displacement surface (42) in the open configuration, the first axis (52) being spaced from the second end by a distance less than the first axis.

4. The locking device of claim 3, the displacement path (58, 158) further including a middle region (64) adjacent the first end (60), the first axis (52) being spaced from the second end by a distance less than the first axis.

5. Locking device according to the preceding claim, the second axis (74) being at a smaller distance from the third axis (98) than the first axis (52).

6. Locking device according to the preceding claim, wherein in the closed configuration the first and second arms of the spring are angled by a first angle (a); in the open position, the included angle is a second angle (b), the difference between the first angle and the second angle is less than 60 degrees, preferably less than 30 degrees, and more preferably less than 20 degrees.

7. Locking device according to claim 2, the first arm (86) of the torsion spring comprising two substantially parallel branches (92), the roller (42) being located between the two branches.

8. Locking device according to the preceding claim, the locking head (32, 132) comprising two inner walls (56, 156) crossed by the first shaft (52).

9. The locking device of claim 8, wherein the displacement path (158) of the locking head (132) is formed by a single piece secured between the double-walled inner walls (156).

10. An aircraft, comprising: a structure (14); a movable panel (18) securable to the structure; and a locking device (12) as claimed in the preceding claim, which is secured to the panel and which, when in the closed configuration, is capable of closing the panel on the structure and obstructing its opening.

Background

The locking device includes: the locking mechanism comprises a panel, a bracket which can be fixed on the panel, a rotary locking head which is hinged on the bracket and surrounds a first shaft, a rotary push rod which is hinged on the bracket and surrounds a second shaft (which is parallel to the first shaft), and a torsion spring which comprises a first arm and a second arm which are connected through at least one spiral component, wherein one ends of the first arm and the second arm are respectively connected with the locking head and the push rod to serve as supports. The locking device is movable between a closed configuration and an open configuration. When the lock is in a closed state, the lock head is connected with the push rod; when the lock is in the opening state, the lock head is not connected with the push rod. The torsion spring is subjected to a first stress when in the closed position which is greater than a second stress when in the open position.

Such locking devices are known from documents FR 255699 and FR 2605671.

The spring of the locking device is generally subjected to high mechanical stresses due to the large spring arm play between the closed configuration and the open configuration. This stress can shorten the service life of the locking device.

Disclosure of Invention

The invention aims to provide an improved locking device, and the service life of a corresponding spring is longer.

To this end, the invention is directed to a locking device of the type described above, which is structured as: the torsion spring has at least one helical fitting on the second shaft; the locking device also comprises a displacement surface which is connected with the end head of the first arm; in the closed and open configuration of the locking device, the lock head comprises a displacement trajectory which is connected with the displacement surface: the displacement surface will move along a displacement trajectory when the locking device is moved between the closed configuration and the open configuration.

According to other advantages of the invention, the locking device comprises one or more of the following features, which may be present alone or in any technically feasible combination:

the displacement surface comprises a roller (on a third axis parallel to the second axis) hinged to the end of the first arm;

-the displacement trajectory comprises a first end and a second end, the second end being connected to the displacement surface in the open configuration, the distance between the first axis and the second end being smaller than the distance between the first axis and the first end;

-the displacement trajectory further comprises a middle region near the first end, the first axis being at a smaller distance from the second end than the first axis;

-the second axis is at a smaller distance from the third axis than the first axis;

in the closed configuration, the first arm and the second arm of the spring are at a first angle; in the open position, the included angle is a second angle. The difference between the first angle and the second angle is less than 60 °, preferably less than 30 °, and more preferably less than 20 °.

The first arm of the torsion spring comprises two substantially parallel branches, between which the roller is located;

the locking head comprises two layers of inner walls passing through the first shaft;

the displacement trajectory of the locking head is constituted by a single piece fixed between the double walls.

The invention can be used in an aircraft, which comprises: a structure; a movable panel securable to the structure; and a locking device as described above, the device being secured to the panel and being capable of locking the panel of the structure open when in the closed configuration.

Drawings

The invention will be understood more clearly on reading the description which follows, by way of non-limiting example and with reference to the accompanying drawings:

fig. 1 is a detailed cross-section of an aircraft including the locking device according to the invention, in a first form of realisation;

FIG. 2 is a cross-sectional view of the locking device of FIG. 1, in a second configuration;

FIG. 3 is an end view of the locking device of FIGS. 1 and 2, in a second configuration; and

fig. 4 is a perspective view of a lock head of a locking device, which is a second form of realisation of the invention.

Detailed Description

Fig. 1 shows an aircraft 10 containing a locking device 12. More precisely, the aircraft 10 further comprises: a structure 14 provided with a compartment 16, and a panel 18 hinged to the structure 14 and allowing the compartment 16 to be opened and closed. As shown in FIG. 1, when the compartment 16 is in the closed configuration, an edge 20 of the panel 18 interfaces with an edge 22 of the structure 14.

Near the edge 20, the panel 18 comprises a perforation 24, preferably of closed profile.

The locking device 12 is mounted on the panel 18 as described below. The following description uses coordinate axes (X, Y, Z) associated with the face plate 18 and the lock device 12, with the Z direction representing the vertical direction.

The panel 18 is divided into two portions, an upper surface 26 and a lower surface 28, both of which lie in the (X, Y) plane. In the closed configuration shown in fig. 1, the lower surface 28 faces the barrier 16.

The locking device 12 shown in fig. 2 and 3 comprises: bracket 30, lock head 32, push rod 34, rivet one 36, rivet two 38, spring 40, and a displacement surface. In the above-described mode of the apparatus, the displacement surface is the roller 42.

The bracket 30 includes a surface 44 (for attachment to the faceplate 18), the surface 44 lying in an (X, Y) plane. As shown in fig. 3, bracket 30 is omega-shaped and includes two upper legs 46 and a mounting surface 44. The legs 46 are provided with fastening holes 48 for fastening to the panel 18.

Bracket 30 further comprises two side faces 50, which lie substantially in the (X, Z) plane. The upper end of the side 50 is formed by a plurality of legs 46. The bracket 30 further comprises a base 51, substantially in the (X, Y) plane, connected to the lower ends of the two sides 50.

The lock head 32 is rotatable relative to the bracket 30 about a first axis 52 (parallel to the Y direction). The locking head 32 is located between the two sides 50 of the bracket. The position of the first shaft 52 is fixed by a first rivet 36 to which the two sides 50 are attached.

Fig. 4 shows a locking head 132 according to a variant of the invention. The locking head 132 is used to replace the locking head 32 in the locking device 12. The locking head 132 and the locking head 32 will be described simultaneously below, and common parts will be identified by the same reference numerals.

The lock head 32, 132 includes: the rotary bodies 53, 153; extension member number one 54; and a second extension member 55.

The rotating bodies 53, 153 are penetrated by the first rivet 36 and positioned on the first shaft 52. In the illustrated embodiment, the rotating bodies 53, 153 are provided with two inner walls 56, 156, one at each end of the first rivet 36, with a compartment between them.

The bodies of revolution 53, 153 each have a displacement path, here a convex curved contour 58, 158. The curved profiles 58, 158 are substantially provided with one or more circular arcs of different radii, one concave face of which is directed towards the first axis 52. In a variant not shown, the displacement trajectory may comprise an inclined plane.

Curved profiles 58, 158 are located between first head 60 and second head 62. The second stub 62 is closer to the first shaft 52 than the first stub 60.

The curved profile 58, 158 includes a middle region 64 near the first end position. The second end 62 is closer to the first shaft 52 than the middle region 64. More preferably, the intermediate region 64 is closer to the first shaft 52 than the first shaft 60.

More preferably, the convex portions of the curved profiles 58, 158 should be free of depressions.

In the implementation illustrated in fig. 1 to 3, the curved profile 58 of the locking head 32 is the same part as the inner wall 56 of the rotating body 53. For example, the curved profile 58 already contains the inner wall edge.

In the embodiment shown in fig. 4, the curved contour 158 of the locking head 132 is a fitting which is located between the inner walls 156 of the rotational body 153 and is fixed thereto. And is secured by rivets 166.

The first extension 54 and the second extension 55 of the lock head 32, 132 extend in a direction perpendicular to the first axis 52 from the rotating body 53, 153. The first extension 54 and the second extension 55 are located on either side of a plane intersecting the first axis 52.

Extension number 54 of lock head 32, 132 includes a number one tongue 70 that forms the movable end of the extension number one.

The second extension 55 of the lock head 32, 132 is provided with a contact surface 72. In the illustrated implementation, the contact surface 72 is planar.

The push rod 34 is rotatable about a second axis 74 (parallel to the Y direction) relative to the bracket 30. The push rod 34 is located between two sides 50 of the bracket. The second shaft 74 is secured by a second rivet 38 to which the two sides 50 are attached.

The push rod 34 is U-shaped and includes a central member 76 and two side members 78 (connected by the central member).

The central member 76 includes a thrust surface 80 and a support surface 82 that are oriented in opposite directions along the Z-axis. Central member 76 also includes a second tongue 83 that lies in the (X, Y) plane in which central member 76 lies. Each side end of the central member is connected to one of the side members 78.

The side members 78 are spaced apart from each other in the Y-axis, and each side member 78 has a second rivet 38 passing therethrough.

The pusher comprises at least one stop 84, 85, lying in a plane parallel to the (X, Y) plane. In the illustrated implementation, central member 76 contains a first stop 84; opposite the central part, each side part contains a stop number two 85. The surfaces of stop number one 84 and stop number two 85 are both facing in the opposite direction to the Z axis.

The spring 40 is a torsion spring made of a metal wire. Torsion spring 40 includes a first arm 86 and a second arm 88 connected by at least one helical member 90. At least one screw member is located around the second rivet 38 between the side members 78 of the pushrod. The helical member comprises at least one helical coil, more preferably a plurality of helical coils.

In the illustrated implementation, first arm 86 and second arm 88 each have two branches 92, 94, respectively, that are substantially parallel to the (X, Z) plane. In addition, spring 40 contains two coil members 90, each positioned on the Y-axis between branch 92 of arm number one and branch 94 of arm number two.

The ends of branches 94 of second arm 88 are connected to each other to form second arm end 96.

Roller 42 is hinged at the end of branch 92 of first arm 86, forming a third axis of rotation 98 parallel to the Y axis. The second axis 74 is less distant from the third axis 98 than the second axis 74 is distant from the first axis 52; thus, the roller shaft 98 is offset in the X-axis relative to the cylinder first shaft 52.

In the implementation shown in fig. 1, the locking device 12 is mounted on a panel 18. The fixed face 44 of the bracket 30 is attached to the panel bottom 28 such that the thrust surfaces 80 of the lock head 32 and the push rod 34 are aligned with the aperture 24 in the panel.

Fig. 1 shows the first configuration of the locking device 12, i.e. the closed configuration (compartment 16 in the closed state).

In the closed configuration of the lock 12, the end 96 of the second arm 88 of the spring 40 contacts the bearing surface 82 of the push rod 34 and the roller 42 abuts the middle region 64 of the curved profile 58 of the lock head 32. First arm 86 and second arm 88 of the spring form a first angle a.

In the closed configuration, the force of the spring 40 on the push rod 34 causes the support surface 82 to be raised. In addition, the force exerted by the roller 42 against the curved profile 58 of the lock 32 is a normal force on the surface of the roller. This normal force is used to rotate the lock cylinder by lifting the extension member number one (including the tongue number one) of the lock cylinder 32.

Stop number one 84 and stop number two 85 of push rod 34 interface with bottom 28 of face plate 18 and bottom 51 of the bracket, respectively, when compartment 16 is in the closed configuration. Further, the upper surface of the first tongue of the lock head 32 is in contact with the lower surface of the second tongue 83 of the push rod 34.

The contact points alternately lock the ram 34 and the lock head 32. The arms 86, 88 of the spring 40 are thus subjected to a first torsional stress.

Furthermore, when the compartment 16 is in the closed condition, the contact surface 72 of the lock head 32 comes into contact with the edge 22 of the structure 14 of the aircraft 10, thus preventing the edge 20 of the panel 18 from coming out of the structure and lifting. The panel 18 is thus locked in the closed configuration.

Preferably, the arrangement of the locking device 12 and the panel 18 is such that the locking head 32 and the thrust surface 80 of the push rod 34 are simultaneously flush with the upper surface 26 of the panel when the compartment 16 is in the closed condition.

Fig. 2 and 3 show the second, open configuration of the locking device 12. The open configuration of the locking device 12 corresponds to the unlocked state of the panel 18. The panel and structure 14 are not shown in fig. 2 and 3.

In the open configuration of the locking device 12, the angle of the locking head 32 relative to the bracket 30 is different from the position in the closed configuration. Specifically, in the open configuration, the first 54 and second 55 extension members of the lock head rotate about the first axis 52, with the lock head 32 lying on a mid-plane perpendicular to the bracket bottom 51. The first tongue 70 of the lock head 32 is spaced from the second tongue 83 of the push rod 34 and the contact surface 72 of the lock head is spaced from the structure 14 of the aircraft 10. The contact surface 72 is blocked by the edge 99 of the base 51, thereby restricting rotation of the lock cylinder about the first shaft 52.

In the open configuration of the lock 12, the end 96 of the second arm 88 of the spring 40 and the pusher 34 are always in contact with the support surface 82 of the pusher 34, and the roller 42 and the second end 55 of the curved profile 53 of the lock head 32. The arms 86, 88 of the spring 40 are thus subjected to a second torsional stress. The second stress is less than the first stress when in the closed configuration with the locking device 12.

First arm 86 and second arm 88 of the spring form a second angle b. In the above-mentioned open configuration, the second angle b is smaller than the first angle a when the locking means 12 is in the closed configuration.

Preferably, the difference between the first angle a and the second angle b is less than 60 °, more preferably less than 30 °, most preferably less than 20 °, in absolute terms.

Next, the procedure for operating the locking device 12 of the aircraft 10 will be described.

The initial state of the compartment 16 and locking device 12 defaults to the closed configuration.

The operator depresses thrust surface 80 of push rod 34, unlocking panel 18 to open compartment 16. The central member 76 of the push rod moves downward causing the push rod 34 to rotate counterclockwise (as viewed in FIG. 1) about the second axis 74. As the push rod rotates, the stress applied to the torsion spring 40 increases. The stress exerted by the roller 42 on the displacement trajectory of the cylinder 32 is also increased. The roller 42 moves from the intermediate region 64 to the first end 60 of the curved profile 58.

The push rod 34 continues to rotate in the counterclockwise direction until the second tongue 83 disengages from the first tongue 70 of the lock head 32. The lock is thus unlocked and, under the force exerted by the roller 42, the lock is caused to rotate due to the misalignment of the roller shaft with the first shaft 52. This rotation is a clockwise rotation of the lock cylinder about the first shaft 52, as shown in fig. 1. Thereby, the contact surface 72 of the lock head 32 is offset from the edge 22 of the structure 14 of the aircraft 10.

During rotation of the lock cylinder 32, the roller 42 moves from the first end 60 to the second end 62 of the curved profile 58. The stress applied to the spring 40 is gradually reduced.

At the same time, once the operator stops pressing on thrust surface 80, pushrod 34 returns to the initial position of the closed configuration, and stop two 85 abuts bottom 51 of bracket 30.

When the roller 42 contacts the second end 62 of the curved profile 58, the locking device 12 is in the open configuration. When the latch interface 72 is misaligned with the structure 14 of the aircraft 10, the panel 18 may be opened.

The direction of movement of the roller 42 in contact with the lock head displacement trajectory is improved due to the different radii of the different regions (60, 62, 64) of the curved profile 58.

Because there is no concavity between the first and second stubs 60, 62, the displacement trajectory (i.e., the roller 42) does not get stuck in the concavity when the push rod 34 is pressed or when the lock cylinder 32 is rotated about the first shaft 52.

To lock the panel 18 again in the closed configuration, the operator presses the lock head 32, causing the first tongue 70 to rotate towards the second tongue 83, causing it to re-engage, to complete the closed configuration of the locking device 12. Thereby, the contact surface 72 of the lock head 32 interfaces with the structure 14 of the aircraft 10.

The locking mechanism provides a small play between the open configuration and the closed configuration, represented by the difference between the angles a and b. The smaller play reduces wear of the spring 40 over time, thereby increasing the service life of the locking device.

In a variant of the locking device 12, which is not shown, the torsion spring 40 is replaced by a spring consisting of a coil and two single arms. Meanwhile, the spring 40 is replaced by a leaf spring.

Since the displacement surface of the locking device 12 is fixed by the roller 42, the friction is reduced, thereby extending the service life of the spring. The displacement surface may not include a roller. In a variation not shown, one or more of the ends 92 of the arms 86 may be unprotected, or may be covered with a lubricating sleeve (e.g., teflon) to improve the sliding connection between the ends 92 of the spring and the curved profile 58 of the lock cylinder.

The various components of the locking device 12 are preferably made of metal (e.g., aluminum or stainless steel) to increase their strength and/or to extend their useful life. Some parts which are less mechanically stressed (e.g. brackets, locks or push rods) may be made of plastic or composite materials. The weight of the locking device can be reduced according to different materials of the components, so that the production is easier and the cost is lower.