1. A path-exploring type measuring head device integrating a confocal method and a trigonometry comprises a measuring head seat (1), a confocal method displacement sensor probe (9), a trigonometry laser displacement sensor (12) and a displacement type sensor mounting assembly; the method is characterized in that: the confocal displacement sensor probe (9) is arranged at the bottom of the head seat (1), and the detection head is arranged downwards; the triangulation laser displacement sensor (12) is connected with the measuring head seat (1) through a displacement type sensor mounting component; the displacement type sensor mounting assembly can drive the triangular laser displacement sensor (12) to lift and drive the position of the triangular laser displacement sensor (12) to be switched on two sides of the confocal displacement sensor probe (9);

the displacement type sensor mounting assembly comprises a first electromagnet (2), a second electromagnet (3), a stepping motor (5), an upper arm (10), a sliding seat (13), a bottom plate (15), a polished rod (16) and a lead screw motor (19); the stepping motor (5) is fixed on the measuring head seat (1); the output axis of the stepping motor (5) is collinear with the central axis of the confocal displacement sensor probe (9); an output shaft of the stepping motor (5) is fixed with one end of the upper arm (10); the other end of the upper arm (10) is fixed with the bottom plate (15); the first electromagnet (2) and the second electromagnet (3) are respectively positioned at two sides of the output axis of the stepping motor (5); the first electromagnet (2) and the second electromagnet (3) are arranged at the same height as the upper arm (10); a first iron block (10-2) and a second iron block (10-3) are respectively arranged on two sides of the lower arm (11); the first iron block (10-2) and the second iron block (10-3) correspond to the first electromagnet (2) and the second electromagnet (3) in position respectively; when the bottom plate (15) reaches a first limit position under the driving of the stepping motor (5), the first electromagnet (2) is contacted with the first iron block (10-2); when the bottom plate (15) reaches a second limit position under the driving of the stepping motor (5), the second electromagnet (3) is contacted with the second iron block (10-3);

the polished rod (16) is fixed on the bottom plate (15), and the axis of the polished rod is parallel to the axis of the stepping motor (5); the screw motor (19) is fixed on the bottom plate (15); the sliding seat (13) is connected with the polish rod (16) in a sliding way; the sliding seat (13) and an output screw of a screw motor (19) form a screw pair; the triangle method laser displacement sensor (12) is fixed on the sliding seat (13); the central line (34) of measuring light emitted by the confocal displacement sensor probe (9) is parallel to the incident light (35) of the triangular laser displacement sensor (12); the central line (34) of measuring light emitted by the confocal method displacement sensor probe (9), the incident light (35) of the triangular method laser displacement sensor (12) and the receiving light (36) are positioned in the same plane.

2. A probing head device integrating confocal measurement and triangulation measurement according to claim 1, wherein: the displacement type sensor mounting assembly also comprises a probe seat cover (8); the probe seat (1) comprises a connecting rod (1-1) and a probe seat (1-2) which are integrally formed; the probe base (1-2) is connected with the probe base cover (8) through a screw, and a confocal displacement sensor probe (9) is clamped; the connecting rod (1-1) is used for being connected with a measuring driving device; the central axis of the connecting rod (1-1) is collinear with the central axis of the confocal displacement sensor probe (9).

3. A probing head device integrating confocal measurement and triangulation measurement according to claim 1, wherein: the displacement type sensor mounting assembly further comprises a lower arm (11); the stepping motor (5) adopts a double-output-shaft motor, and two ends of an output shaft are respectively fixed with one end of the upper arm (10) and one end of the lower arm (11); the other end of the lower arm (11) is fixed with the bottom plate (15).

4. A probing head device according to claim 3 wherein said probing head device integrates confocal and trigonometric methods and further comprises: the displacement type sensor mounting assembly further comprises a first positioning column (6) and a second positioning column (7); the first positioning column (6) and the second positioning column (7) are respectively positioned at two sides of the output axis of the stepping motor (5); the first positioning column (6) and the second positioning column (7) are arranged at the same height as the lower arm (11); semi-ball sockets are arranged at the outer end parts of the first positioning column (6) and the second positioning column (7); a second hemisphere (11-3) and a first hemisphere (11-2) are respectively arranged on two sides of the inner end of the lower arm (11); the radiuses of the first hemisphere (11-2) and the second hemisphere (11-3) are respectively equal to the radiuses of hemisphere sockets at the ends of the first positioning column (6) and the second positioning column (7); the first hemisphere (11-2) and the second hemisphere (11-3) correspond to the first positioning column (6) and the second positioning column (7) in position respectively.

5. A method of measuring a probing head device integrating confocal method and triangulation method according to claim 1, wherein: step one, a measuring head seat (1) is arranged at the tail end of a measuring driving device;

calibrating the measuring range of the confocal method displacement sensor in the measuring range of the triangular method laser displacement sensor (12), so that whether the confocal method displacement sensor can meet the measuring range requirement when reaching a measuring point can be known after the triangular method laser displacement sensor (12) measures at the measuring point;

step three, placing the measured object in the motion range of the measuring head device, and establishing a measuring coordinate system;

driving the triangular laser displacement sensor (12) to reach the upper part of the measured object by the measuring driving device, and enabling the output measured value of the triangular laser displacement sensor (12) to be the range midpoint value of the triangular laser displacement sensor;

driving a triangular laser displacement sensor (12) to transversely move by a measurement driving device, and transversely scanning the surface of the measured object point by point; when the triangulation laser displacement sensor (12) detects that a measured position exceeds the measuring range of the confocal displacement sensor, marking the measured point as an over-distance measuring point; each over-distance measuring point corresponds to an over-distance adjusting distance delta; when the confocal displacement sensor positioned right above the over-distance measuring point moves downwards by the corresponding over-distance adjusting distance delta, the over-distance measuring point enters the measuring range of the confocal displacement sensor;

every time when the confocal method displacement sensor reaches the position right above one over-distance measuring point, downward movement measurement is carried out; the process of the downshifting measurement is as follows: a screw motor (19) drives a triangular laser displacement sensor (12) to move upwards for a distance to a position where the triangular laser displacement sensor is prevented from touching a measured object, meanwhile, a measurement driving device drives the whole measuring head device to move downwards for an over-distance adjusting distance delta corresponding to a current over-distance measuring point, the confocal displacement sensor measures the distance of the over-distance measuring point, and the obtained distance value increased delta is the corresponding actual distance value of the over-distance measuring point; after the measurement of the over-distance measuring point is finished, the lead screw motor (19) drives the triangular laser displacement sensor (12) to move downwards for resetting, and the measurement driving device drives the whole measuring head device to move upwards for resetting;

sixthly, after the confocal method displacement sensor finishes one-time transverse scanning on the surface of the measured object, the measurement driving device drives the whole side head device to move a safe distance in the direction away from the measured object; the second electromagnet (3) is powered off, the first electromagnet (2) is powered on, and the stepping motor (5) drives the upper arm (10) to move from the first limit position to the second limit position, so that the triangular laser displacement sensor (12) moves to one side of the confocal displacement sensor, which is close to the measured object; then, the measuring driving device drives the measuring head device to longitudinally move for a measuring step length;

step seven, the measuring driving device drives the measuring head device to perform transverse point-by-point scanning along the direction opposite to the direction of the step five, and the specific process is the same as the step five;

step eight, after the confocal method displacement sensor finishes one-time transverse scanning of the surface of the measured object, the measurement driving device drives the whole side head device to move a safe distance in the direction away from the measured object; the first electromagnet (2) is powered off, the second electromagnet (3) is powered on, and the stepping motor (5) drives the upper arm (10) to move from the second limit position to the first limit position, so that the triangular laser displacement sensor (12) moves to one side of the confocal displacement sensor, which is close to the measured object; then, the measuring driving device drives the measuring head device to longitudinally move for a measuring step length;

and step nine, repeating the step five to the step eight until the surface of the measured object is completely scanned, and obtaining the measurement data.

6. The measurement method according to claim 5, characterized in that: the triangulation laser displacement sensor (12) is a point triangulation laser displacement sensor.

7. The measurement method according to claim 5, characterized in that: the measurement step ζ satisfies the following relationWherein, the distance between the central line (34) of the measuring light emitted by the confocal method displacement sensor probe (9) and the incident light (35) of the trigonometry laser displacement sensor (12); n is a positive integer.

8. The measurement method according to claim 5, characterized in that: the over-distance measurement value delta is smaller than the measurement value of the triangular laser displacement sensor (12) at the corresponding over-distance measurement point and is larger than the difference value obtained by subtracting the measuring range of the confocal displacement sensor probe (9) from the measurement value of the triangular laser displacement sensor (12) at the corresponding over-distance measurement point.

9. The measurement method according to claim 5, characterized in that: the measuring driving device adopts a three-standard measuring machine.

10. The measurement method according to claim 5, characterized in that: in the second step, the method for calibrating the range of the displacement sensor by the confocal method in the range of the laser displacement sensor (12) by the triangulation method comprises the following specific steps:

(1) the measuring driving device drives the whole measuring head device to move, so that the output measuring value of the confocal displacement sensor is the minimum value x of the measuring range₁(ii) a The lead screw motor (19) drives the triangular laser displacement sensor (12) to perform lifting motion, so that the output measurement value of the triangular laser displacement sensor (12) is the minimum value h of the measurement range₁；

(2) The measuring driving device drives the whole measuring head device to move upwards by a distance x, wherein x is the calibration range of the confocal displacement sensor when leaving the factory, and the output measured value of the confocal displacement sensor is the maximum value x of the range₂And recording the output measurement value h' of the triangular laser displacement sensor (12) at the moment; when the output measurement value of the triangular method laser displacement sensor (12) is larger than h', the measurement point is judged to be beyond the measuring range of the confocal method displacement sensor.

Background

In the fields of automobile manufacturing, aerospace, reverse engineering, integrated circuit board printing or welding and the like, in order to meet the requirements of external dimensions, installation positions and the like, high-precision measurement is often required to be performed on the surface of a workpiece so as to realize a predetermined function.

The current measuring modes are mainly divided into a contact type and a non-contact type, the contact type measuring precision is high, but a measuring head needs to be in direct contact with the surface of a measured object during measurement, so that the measurement cannot be carried out on products with surfaces which are not allowed to be in contact or soft in texture. Non-contact measurement has no contact force, and the measurement accuracy is continuously improved, so that in many measurement occasions, non-contact measurement is gradually replacing contact measurement.

The non-contact measurement mainly includes electromagnetic wave measurement, ultrasonic wave measurement, optical measurement, and the like. The electromagnetic wave measurement is only limited to the measurement of metal materials, and the divergence angle of ultrasonic measurement is large and the directivity is poor. In contrast, optical measurement has the advantages of fast frequency response, simple structure, no special requirement on the material of the measured object and the like, and is most widely applied in the field of non-contact shape measurement.

Currently, commonly used optical shape measurement methods include a laser triangulation method, a structured light method, a time-of-flight method, a confocal method, and the like. The laser triangulation method has high measurement precision when the measuring range is small, and the measurement precision is greatly reduced when the measuring range is large; the measurement principle is as follows: the laser emits laser, the laser is incident to the surface of a measured object, and diffuse reflection light is generated on the surface of the measured object; then, a part of the diffuse reflection light is converged through a focusing lens, and the converged diffuse reflection light forms light spots on the position sensitive element; and finally, measuring the displacement of the light spot to indirectly obtain an actual displacement measurement value. The range of the confocal method is usually small, but the measurement precision is high, and the confocal method is generally applied to high-precision measurement occasions. The measurement principle of the confocal method is as follows: the measuring light source emits a beam of white light, spectral dispersion is carried out through the dispersion lens, monochromatic light with different wavelengths is formed, the focus of each monochromatic light wavelength corresponds to a distance value, when the dispersed light irradiates the surface of a measured object and is reflected, only light meeting confocal conditions can pass through the small hole and be detected by the spectrograph, and the measured distance value can be indirectly obtained by calculating the wavelength of the detected focus light.

The existing non-contact displacement measuring sensor can only take one of the measuring range and the precision. However, in the actual displacement detection occasion, some occasions with high requirements on not only the measurement accuracy but also the range are often encountered, and at this time, the existing sensor is often not capable of meeting the requirements.

For the problems, the method usually adopted is to measure the measured object twice respectively, namely, firstly, a large-range sensor is used for rough measurement, and then, data obtained by rough measurement is used for carrying out accurate measurement on a high-precision sensor for planning a measurement path, so that the high-precision sensor is ensured to work in a range all the time in the measurement process. However, when the method is applied to a production field, time cost and equipment cost are increased, and in the process of mounting the sensor twice, mounting errors of the sensor are introduced, so that the final measurement accuracy is affected.

Disclosure of Invention

The invention aims to provide a path-exploring type measuring head device integrating a confocal method and a trigonometry and a measuring method thereof.

The invention discloses a path-exploring type measuring head device integrating a confocal method and a trigonometry, which comprises a measuring head seat, a confocal method displacement sensor probe, a trigonometry laser displacement sensor and a displacement sensor mounting assembly. The confocal displacement sensor probe is arranged at the bottom of the measuring head seat, and the measuring head is arranged downwards. The triangulation laser displacement sensor is connected with the measuring head seat through a displacement type sensor mounting component. The displacement type sensor mounting assembly can drive the triangulation laser displacement sensor to lift, and the position of the triangulation laser displacement sensor is driven to be switched on two sides of the probe of the confocal displacement sensor.

The displacement type sensor mounting assembly comprises a first electromagnet, a second electromagnet, a stepping motor, an upper arm, a sliding seat, a bottom plate, a polished rod and a lead screw motor; the stepping motor is fixed on the measuring head seat; the output axis of the stepping motor is collinear with the central axis of the confocal displacement sensor probe. An output shaft of the stepping motor is fixed with one end of the upper arm. The other end of the upper arm is fixed with the bottom plate. The first electromagnet and the second electromagnet are respectively positioned on two sides of the output axis of the stepping motor. The first electromagnet and the second electromagnet are arranged at the same height with the upper arm. A first iron block and a second iron block are respectively arranged on two sides of the lower arm; the first iron block and the second iron block correspond to the first electromagnet and the second electromagnet in position respectively. When the bottom plate reaches a first limit position under the driving of the stepping motor, the first electromagnet is contacted with the first iron block. When the bottom plate reaches a second limit position under the driving of the stepping motor, the second electromagnet is contacted with the second iron block.

The polished rod is fixed on the bottom plate, and the axis of the polished rod is parallel to the axis of the stepping motor. The screw motor is fixed on the bottom plate; the sliding seat is connected with the polish rod in a sliding way; the sliding seat and an output screw of the screw motor form a screw pair. The triangle method laser displacement sensor is fixed on the sliding seat. The central line of measuring light emitted by a probe of the confocal method displacement sensor is parallel to the incident light of the triangular method laser displacement sensor; the central line of the measuring light emitted by the confocal method displacement sensor probe, the incident light and the receiving light of the triangular method laser displacement sensor are positioned in the same plane.

Preferably, the displaceable sensor mounting assembly further comprises a probe seat cover. The probe seat comprises a connecting rod and a probe seat which are integrally formed. The probe base is connected with the probe base cover through a screw, and a confocal displacement sensor probe is clamped; the connecting rod is used for being connected with the measuring driving device. The central axis of the connecting rod is collinear with the central axis of the confocal displacement sensor probe.

Preferably, the displaceable sensor mounting assembly further comprises a lower arm. The stepping motor adopts a double-output-shaft motor, and two ends of an output shaft are respectively fixed with one end of an upper arm and one end of a lower arm. The other end of the lower arm is fixed with the bottom plate.

Preferably, the displacement sensor mounting assembly further comprises a first positioning column and a second positioning column. The first positioning column and the second positioning column are respectively positioned at two sides of the output axis of the stepping motor. The first positioning column and the second positioning column are arranged at the same height with the lower arm. Half ball sockets are respectively arranged at the outer end parts of the first positioning column and the second positioning column. A second hemisphere and a first hemisphere are respectively arranged on two sides of the inner end of the lower arm; the radiuses of the first hemisphere and the second hemisphere are equal to the radiuses of the hemisphere sockets at the end parts of the first positioning column and the second positioning column respectively. The first hemisphere and the second hemisphere correspond to the first positioning column and the second positioning column respectively in position.

The method for measuring the path-exploring type measuring head device integrating the confocal method and the trigonometry comprises the following steps:

step one, mounting a measuring head seat at the tail end of a measuring driving device.

And step two, calibrating the measuring range of the confocal method displacement sensor in the measuring range of the triangular method laser displacement sensor, so that whether the confocal method displacement sensor can meet the measuring range requirement when reaching a measuring point can be known after the triangular method laser displacement sensor measures at the measuring point.

And step three, placing the measured object in the motion range of the measuring head device, and establishing a measurement coordinate system.

And fourthly, driving the triangular laser displacement sensor to reach the upper part of the measured object by the measurement driving device, and enabling the output measurement value of the triangular laser displacement sensor to be the self range midpoint value.

And step five, driving the triangular laser displacement sensor to transversely move by the measuring driving device, and transversely scanning the surface of the measured object point by point. When the triangular method laser displacement sensor detects that a measuring position is beyond the measuring range of the confocal method displacement sensor, the measuring point is marked as an over-distance measuring point. Each over-distance measuring point corresponds to an over-distance adjusting distance delta. When the confocal displacement sensor positioned right above the over-distance measuring point moves downwards by the corresponding over-distance adjusting distance delta, the over-distance measuring point enters the measuring range of the confocal displacement sensor.

Every time the confocal method displacement sensor reaches a position right above one over-distance measurement point, one downward movement measurement is performed. The process of the downshifting measurement is as follows: the screw motor drives the triangle method laser displacement sensor to move upwards to a position where the triangle method laser displacement sensor is prevented from touching a measured object, meanwhile, the measurement driving device drives the whole measuring head device to move downwards after the distance adjusting distance delta corresponding to the current distance measuring point is reached, the confocal method displacement sensor carries out distance measurement on the distance measuring point, and the obtained distance value is increased delta, namely the corresponding actual distance value of the distance measuring point. After the measurement of the over-distance measuring point is completed, the lead screw motor drives the triangle laser displacement sensor to move downwards for resetting, and the measurement driving device drives the whole measuring head device to move upwards for resetting.

And sixthly, after the confocal method displacement sensor finishes one-time transverse scanning on the surface of the measured object, the measurement driving device drives the whole side head device to move a safe distance in the direction away from the measured object. And the second electromagnet is powered off, the first electromagnet is powered on, and the stepping motor drives the upper arm to move from the first limit position to the second limit position, so that the triangulation laser displacement sensor moves to one side of the confocal displacement sensor close to the measured object. And then, the measuring driving device drives the measuring head device to longitudinally move for one measuring step length.

And step seven, the measuring driving device drives the measuring head device to perform transverse point-by-point scanning along the direction opposite to the step five, and the specific process is the same as the step five.

And step eight, after the confocal method displacement sensor finishes one-time transverse scanning of the surface of the measured object, the measurement driving device drives the whole side head device to move a safe distance in the direction away from the measured object. The first electromagnet is powered off, the second electromagnet is powered on, and the stepping motor drives the upper arm to move from the second limit position to the first limit position, so that the triangulation laser displacement sensor moves to one side of the confocal displacement sensor close to the measured object. And then, the measuring driving device drives the measuring head device to longitudinally move for one measuring step length.

And step nine, repeating the step five to the step eight until the surface of the measured object is completely scanned, and obtaining the measurement data.

Preferably, the triangulation laser displacement sensor is a point triangulation laser displacement sensor.

Preferably, the measurement step ζ satisfies the following relational expressionThe distance between the central line of the measuring light emitted by the probe of the confocal method displacement sensor and the incident light of the triangular method laser displacement sensor is measured; n is a positive integer.

Preferably, the over-distance measurement value delta is smaller than the measurement value of the triangular laser displacement sensor at the corresponding over-distance measurement point and is larger than the difference value obtained by subtracting the measuring range of the confocal displacement sensor probe from the measurement value of the triangular laser displacement sensor at the corresponding over-distance measurement point.

Preferably, the measuring driving device adopts a three-standard measuring machine.

Preferably, in the second step, the method for calibrating the range of the displacement sensor by the confocal method in the range of the laser displacement sensor by the triangulation method specifically comprises the following steps:

(1) the measuring driving device drives the whole measuring head device to move, so that the output measuring value of the confocal displacement sensor is the minimum value x of the measuring range₁(ii) a The lead screw motor drives the triangle laser displacement sensor to perform lifting motion, so that the output measurement value of the triangle laser displacement sensor is the minimum value h of the measurement range₁。

(2) The measuring driving device drives the whole measuring head device to move upwards by a distance x, wherein x is the calibration range of the confocal displacement sensor when leaving the factory, and the output measured value of the confocal displacement sensor is the maximum value x of the range₂And recording the output measurement value of the triangular laser displacement sensor as h'. And when the output measurement value of the triangular laser displacement sensor is larger than h', judging that the measurement point is out of the range of the confocal displacement sensor.

The invention has the beneficial effects that:

1. the invention carries out path detection through the triangulation laser displacement sensor, achieves the measurement precision of the confocal displacement sensor in the measuring range of the triangulation laser displacement sensor, and can meet the non-contact measurement occasion with large measuring range and high precision.

2. The invention fully combines the unique measurement advantages of the triangular laser displacement sensor and the confocal displacement sensor into a whole, realizes automatic path detection by motor driving, and has simple integral structure and easy maintenance.

3. Compared with the traditional measuring mode, the invention can improve the measuring efficiency to a certain extent and reduce the measuring time cost.

Drawings

Fig. 1 is a perspective view of a first overall structure of a probe device provided by the invention;

fig. 2 is a perspective view of a second overall structure of the measuring head device provided by the invention;

fig. 3 is a front view of the overall structure of the measuring head device provided by the invention;

fig. 4 is a schematic diagram illustrating the proving of a probe seat in the probe device provided by the present invention;

fig. 5 is a partial structural schematic diagram of a displacement sensor mounting assembly in the probe device provided by the invention;

fig. 6 is a perspective view of a sliding seat in the probe device provided by the present invention;

fig. 7 is a perspective view of an upper arm of the probe device provided in the present invention;

fig. 8 is a perspective view of a lower arm in the probe device according to the present invention;

fig. 9 is a schematic view of the measuring head device provided by the invention in the + Y direction;

fig. 10 is a schematic view of the measuring head device provided by the invention in the-Y direction;

fig. 11 is a schematic diagram of a distance relationship measured in real time by the measuring head device provided by the invention.

In the figure: 1. a measuring head seat, 1-1, a connecting rod, 1-2, a probe seat, 2, a first electromagnet, 3, a second electromagnet, 4, a first motor seat, 5, a stepping motor, 6, a first positioning column, 7, a second positioning column, 8, a probe seat cover, 9, a confocal displacement sensor probe, 10, an upper arm, 10-1, a first cylindrical through hole, 10-2, a first iron block, 10-3, a second iron block, 10-4, a first U-shaped groove, 11, a lower arm, 11-1, a second cylindrical through hole, 11-2, a first hemisphere, 11-3, a second hemisphere, 11-4, a second U-shaped groove, 12, a laser displacement sensor, 13, a sliding seat, 13-1, a first connecting seat, 13-2, a second connecting seat, 14, a first mounting seat, 15, a bottom plate, 16, a polish rod, 17, a second motor seat, 18. second mount, 19, screw motor, 20, first screw, 21, second screw, 22, first bolt group, 23, second bolt group, 24, third bolt group, 25, fourth bolt group, 26, third screw, 27, fourth screw, 28, fifth screw, 29, fifth bolt group, 30, sixth screw, 31, seventh screw, 32, eighth screw, 33, sixth bolt group, 34, center line of measuring light, 35, incident light, 36, received light.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

As shown in fig. 1,2,3, 4, 5, 6, 7, 8 and 11, a probe head device integrating confocal method and triangulation method includes a head base 1, a confocal method displacement sensor probe 9, a triangulation method laser displacement sensor 12 and a displacement sensor mounting assembly. The confocal displacement sensor probe 9 is arranged at the bottom of the head base 1, and the detection head is arranged downwards. The triangulation laser displacement sensor 12 is connected with the measuring head seat 1 through a displacement type sensor mounting component. The displacement type sensor mounting assembly can drive the triangulation laser displacement sensor 12 to lift and drive the triangulation laser displacement sensor 12 to move to two sides of the confocal displacement sensor probe 9, so that the confocal displacement sensor probe 9 can share the same triangulation laser displacement sensor 12 when moving in opposite directions.

The displacement type sensor mounting assembly comprises a first electromagnet 2, a second electromagnet 3, a first motor base 4, a stepping motor 5, a first positioning column 6, a second positioning column 7, a probe base cover 8, an upper arm 10, a lower arm 11, a sliding base 13, a first mounting base 14, a bottom plate 15, a polished rod 16, a second motor base 17, a second mounting base 18 and a lead screw motor 19; the first motor base 4 is connected with the measuring head base 1 through a fifth bolt set 29. The first motor base 4 is connected with the stepping motor 5 through a first screw 20; the probe seat 1 comprises a connecting rod 1-1 and a probe seat 1-2 which are integrally formed. The probe seat 1-2 is connected with the probe seat cover 8 through a second screw 21 and clamps the confocal displacement sensor probe 9; the connecting rod 1-1 is positioned at the top of the probe seat 1-2. The central axis of the connecting rod 1-1, the output axis of the stepping motor 5 and the central axis of the confocal method displacement sensor probe 9 are collinear.

The stepping motor 5 adopts a double-output-shaft motor, and two ends of an output shaft are respectively fixed with one end of an upper arm 10 and one end of a lower arm 11. The other ends of the upper arm 10 and the lower arm 11 are fixed with the bottom plate 15. Specifically, the inner end of the upper arm 10 is provided with a first cylindrical through hole 10-1, and the outer end is provided with a first U-shaped groove 10-4; the first cylindrical through hole 10-1 is in interference connection with the top end of an output shaft of the stepping motor 5; the first U-shaped grooves 10-4 are clamped at both sides of the bottom plate 15 and connected by a first bolt group 22. The inner end of the lower arm 11 is provided with a second cylindrical through hole 11-1, and the outer end is provided with a second U-shaped groove 11-4; the second cylindrical through hole 11-1 is in interference connection with the bottom end of the output shaft of the stepping motor 5; the second U-shaped groove 11-4 is clamped at both sides of the bottom plate 15 and connected by a second bolt group 23. The first electromagnet 2 is connected with the measuring head seat 1 through a fourth screw 27; the second electromagnet 3 is connected with the measuring head seat 1 through a fifth screw 28; the first positioning column 6 is connected with the measuring head seat 1 through a sixth screw 30; the second positioning column 7 is connected with the measuring head seat 1 through a seventh screw 31;

the first positioning column 6 and the second positioning column 7 are respectively positioned at two sides of the axis of the output shaft of the stepping motor 5. The first positioning column 6 and the second positioning column 7 are arranged at the same height with the lower arm 11. Half ball sockets are respectively arranged at the end parts of the outer ends of the first positioning column 6 and the second positioning column 7. A second hemisphere 11-3 and a first hemisphere 11-2 are respectively arranged on two sides of the inner end of the lower arm 11; the radiuses of the first hemisphere 11-2 and the second hemisphere 11-3 are equal to the radiuses of hemisphere sockets at the ends of the first positioning column 6 and the second positioning column 7 respectively. The first hemisphere 11-2 and the second hemisphere 11-3 correspond to the first positioning column 6 and the second positioning column 7 in position respectively, and are used for realizing accurate positioning of the bottom plate 15 at two limit positions.

The first electromagnet 2 and the second electromagnet 3 are respectively positioned at two sides of the output axis of the stepping motor 5. The first electromagnet 2 and the second electromagnet 3 are arranged at the same height with the upper arm 10. A first iron block 10-2 and a second iron block 10-3 are respectively arranged on two sides of the inner end of the lower arm 11; the first iron block 10-2 and the second iron block 10-3 correspond to the first electromagnet 2 and the second electromagnet 3 in position respectively, and are used for providing fastening force when the bottom plate 15 is at two limit positions and keeping the relative positions of the confocal method displacement sensor probe 9 and the triangulation method laser displacement sensor 12 stable.

The first mounting seat 14 is connected with the bottom of the side surface of the bottom plate 15 through a fourth bolt group 25; the second mounting seat 18 is connected with the top of the side surface of the bottom plate 15 through a third bolt group 24; the two ends of the polish rod 16 are fixed to the first and second mounting seats 14 and 18, respectively.

The second motor base 17 is connected to the base plate 15 by a sixth bolt group 33. The second motor base 17 is connected with the screw motor 19 through a third screw 26; the sliding seat 13 is connected with the polish rod 16 in a sliding way; the slide base 13 and the output screw of the screw motor 19 form a screw pair. Specifically, the sliding seat 13 is provided with a first connecting seat 13-1 and a second connecting seat 13-2; the first connecting seat 13-1 is provided with a through hole with trapezoidal threads and can be matched with an output screw of a screw motor 19; the second connecting seat 13-2 is provided with a cylindrical through hole which can be in clearance fit with the polish rod 16.

The trigonometry laser displacement sensor 12 is connected to the slide base 13 by an eighth screw 32. The first electromagnet 2, the second electromagnet 3, the stepping motor 5, the lead screw motor 19 and the trigonometry laser displacement sensor 12 are respectively connected with a controller; the confocal method displacement sensor probe 9 is connected with the controller to form a confocal method displacement sensor, and a central line 34 of measuring light emitted by the confocal method displacement sensor probe 9 is parallel to incident light 35 of the triangular method laser displacement sensor 12; the central line 34 of the measuring light emitted by the confocal displacement sensor probe 9, the incident light 35 of the triangular laser displacement sensor 12 and the receiving light 36 are positioned in the same plane.

The triangulation laser displacement sensor 12 is a point triangulation laser displacement sensor.

The measuring head base 1, the first positioning column 6, the second positioning column 7, the probe base cover 8, the upper arm 10, the lower arm 11, the sliding base 13, the first mounting base 14, the bottom plate 15 and the second mounting base 18 are all made of aviation aluminum materials.

As shown in fig. 9, 10 and 11, the measurement method of the probe-type probe apparatus integrating the confocal method and the triangulation method specifically includes the following steps:

the method comprises the following steps: the measuring head device is fixedly installed with the Z axis of the three-standard measuring machine through the measuring head seat 1, so that the central line 34 of measuring light emitted by the confocal method displacement sensor probe 9 and the incident light 35 of the triangular method laser displacement sensor 12 are parallel to the Z axis of the three-coordinate measuring machine.

Step two: calibrating the range of the confocal displacement sensor within the range of the trigonometry laser displacement sensor 12, and calibrating the range x of the confocal displacement sensor₁x₂Corresponding to the interval h within the range of the trigonometric laser displacement sensor 12₁h′。

Step three: the object to be measured is placed in a suitable posture in the measurable area of the three-coordinate measuring machine platform and a measuring coordinate system is established on the basis of the X, Y, Z coordinate axes of the three-coordinate measuring machine.

Step four: moving the measuring head device to the upper part of the measured object, and adjusting the position of the Z axis of the three-coordinate measuring machine in the vertical direction, thereby adjusting the position of the measuring head device in the vertical direction and enabling the output measurement value of the trigonometric laser displacement sensor 12 to be the midpoint value h of the measuring range₀。

Step five: the measuring head device is driven by a Z axis of the three-coordinate measuring machine to perform horizontal point-by-point scanning measurement on the surface of the measured object in an XY plane of the three-coordinate measuring machine. Firstly, the triangulation laser displacement sensor 12 scans and measures the surface of the measured object point by point in the transverse direction (in the direction of + Y in the drawing) according to the step length zeta; then, the output measurement value of the triangular laser displacement sensor 12 is determined whether or not it is in the section h₁And h', judging whether the confocal displacement sensor exceeds the range of the measuring range when measuring the point in real time. If the output measurement value of the trigonometric laser displacement sensor 12 is in the interval h₁h', it can be determined that the confocal displacement sensor does not measure the point beyondRange of measurement, directly measuring and storing the measured data as (x)_n,y_n,z_n) Wherein n is 1,2,3, … …. If the output measurement value of the trigonometry laser displacement sensor 12 is not in the interval h₁Within h '(i.e., the interval h' h in FIG. 11)₂Inner), it can be determined that the confocal displacement sensor will exceed its range when measuring the point; when the confocal method displacement sensor is about to measure the point, the upper computer calculates the downward translation distance delta of the Z-axis of the three-coordinate measuring machine according to the output measurement value of the triangular method laser displacement sensor 12, so that the measurement point falls into the range of the measuring range of the confocal method displacement sensor after the confocal method displacement sensor moves down by the distance delta, meanwhile, the upper computer drives the output shaft of the screw motor 19 to rotate in the positive direction (clockwise rotation when looking down the measuring head device) through the controller, and the triangular method laser displacement sensor 12 moves up by the distance delta h to a safe position under the drive of the sliding seat 13, so as to prevent the measured object from being impacted; then, the three-coordinate measuring machine drives the measuring head device to move downwards by a distance delta along the Z coordinate direction; finally, the measurement is performed and the measurement data is saved as (x)_n,y_n,z_nδ), where n is 1,2,3, … …, after the measurement data is saved, the Z-axis of the coordinate measuring machine drives the probe device to move up by a distance δ along the Z-coordinate direction, and the upper computer drives the output shaft of the lead screw motor 19 to rotate reversely (counterclockwise rotation when looking down the probe device) through the controller, so as to move the trigonometric laser displacement sensor 12 down by a distance Δ h under the driving of the sliding seat 13.

Step six: and repeating the process of the fifth step, scanning the surface of the measured object point by point in the transverse direction (the + Y direction in the attached drawing), and when the first line is scanned, continuing to advance the measuring head device to a safe position by a safe distance s along the transverse (the + Y direction in the attached drawing) scanning direction. Then, the second electromagnet 3 is powered off, the first electromagnet 2 is powered on, the upper computer drives the output shaft of the stepping motor 5 to rotate 180 degrees clockwise (when looking down the probe device) through the controller until the first electromagnet 2 is attached to and attracted by the first iron block 10-2 in the upper arm 10, and meanwhile, the first positioning column 6 is matched with the first hemisphere 11-2 in the lower arm 11, and the stepping motor 5 stops working.

Step seven: the measuring head device is driven by the three-coordinate measuring machine to advance along the longitudinal direction by a distance step zeta, then the second row is scanned point by point in the transverse direction (the-Y direction in the attached drawing), and the point by point scanning method is the same as the step five.

Step eight: when the second row is scanned, the stylus device continues to advance in the transverse (Y-direction in the drawing) scanning direction for a safety distance s to a safety position. Then, the first electromagnet 2 is powered off, the second electromagnet 3 is powered on, the upper computer drives the output shaft of the stepping motor 5 to rotate 180 degrees in the anticlockwise direction through the controller (when looking down the measuring head device), until the second electromagnet 3 is attached to and attracted by the second iron block 10-3 in the upper arm 10, and meanwhile, the second positioning column 7 is matched with the second hemisphere 11-3 in the lower arm 11, and the stepping motor 5 stops working.

Step nine: and the measuring head device is driven by the three-coordinate measuring machine to advance along the longitudinal direction by a distance step zeta, then the third row is scanned transversely point by point, and the point by point scanning method is the same as the step five.

Step ten: and repeating the fifth step, the sixth step, the seventh step, the eighth step and the ninth step until the whole scanning of the surface of the measured object is finished and the measured data is obtained.

Further, the step size ζ should satisfy the following condition:

in the formula, L₂Is the distance between the central line 34 of the measuring light emitted from the confocal displacement sensor probe 9 and the incident light 35 of the triangulation laser displacement sensor 12.

Further, the upper computer calculates the downward translation distance δ of the three-coordinate measuring machine Z axis according to the output measurement value of the trigonometry laser displacement sensor 12, and the following condition is satisfied:

wherein h' is the output measurement of the trigonometric laser displacement sensor 12 when the measurement value output by the confocal method displacement sensor is the maximum value of the measurement rangeMagnitude, h_xThe output measurement value of the triangular laser displacement sensor 12 at the real-time measurement point of the confocal displacement sensor is obtained.

Further, the relationship between the number of rotations of the screw motor 19 and the distance Δ h from the laser displacement sensor 12 to the safety position is:

in the formula, N is the number of rotation turns of the screw motor 19, Δ h is a distance value of the laser displacement sensor 12 moving up to the safety position, and L is a lead of the trapezoidal thread of the output shaft of the screw motor 19.

Further, in order to prevent the triangulation laser displacement sensor 12 from impacting the object to be measured, the distance Δ h that the triangulation laser displacement sensor 12 moves up to the safe position should satisfy the following condition:

Δh≥h

in the formula, h is the factory calibration range value of the trigonometric laser displacement sensor 12.

To further explain, in order to prevent the bottom of the bottom plate 15 from impacting the object to be measured, the distance L between the bottom of the bottom plate 15 and the bottom of the confocal displacement sensor probe 9 is set₁The following conditions should be satisfied:

L₁≥h

in the formula, h is the factory calibration range value of the trigonometric laser displacement sensor 12.

Further, in order to prevent the probe path portion of the probe device from impacting the object to be measured after each line of measurement is completed, the safety distance s that the probe device advances along the transverse scanning direction should satisfy the following conditions:

s≥L₃

in the formula, L₃Is the distance between the end surface of the outer side of the sliding seat 13 and the central line of the connecting rod 1-1.

In the measuring range of the triangulation laser displacement sensor 12, the method for calibrating the measuring range of the confocal displacement sensor specifically comprises the following steps:

(1) the second electromagnet 3 is electrified, and the upper computer controls the output shaft of the stepping motor 5 to rotate reversely through the controller until the second electromagnet 3 is attached to and absorbed by the second iron block 10-3 in the upper arm 10. Meanwhile, the second positioning column 7 is matched with a second hemisphere 11-3 in the lower arm 11, and the stepping motor 5 stops working.

(2) Adjusting the position of the measuring head device in the Z-axis direction of the three-coordinate measuring machine to make the output measurement value of the confocal displacement sensor be the minimum value x of the measuring range₁Then the upper computer controls the screw motor 19 to output the screw to rotate through the controller, and adjusts the height of the triangle laser displacement sensor 12 to enable the output measurement value of the triangle laser displacement sensor 12 to be the minimum value h of the measuring range₁。

(3) Moving the three-coordinate measuring machine by x distance in the Z-axis direction, wherein x is the calibration range of the displacement sensor in the confocal method when leaving the factory, and adjusting the position of the measuring head device on the Z-coordinate axis of the three-coordinate measuring machine to make the output measurement value of the displacement sensor in the confocal method be the maximum value x of the range₂And the output measurement value of the trigonometric laser displacement sensor 12 at this time is recorded as h'.

(4) The measuring range of the calibrated confocal displacement sensor is recorded in the measuring range of the triangular laser displacement sensor 12, and the measuring range of the calibrated confocal displacement sensor is h₁h′。