Integrated Multi-Axis Force and Torque Sensor

Abstract

The present application provides an integrated multi-axis force and torque sensor, which relates to the technical field of force and torque sensors. It includes: a fixed box, an elastic component, a movable cover, a metal plate and a measurement component. The elastic component is arranged inside the fixed box and connected to the inner wall of the fixed box; the movable cover is arranged at the box opening of the fixed box and connected to the elastic component; the metal plate is arranged between the elastic component and the inner bottom wall of the fixed box and connected to the elastic component; the measurement component is arranged between the metal plate and the inner bottom wall of the fixed box and can detect the displacement or rotation of the metal plate. The present application has the advantages of relatively low production cost and relatively simple production process.

Description

Technical Field

[0001] This application relates to the technical field of force and torque sensors, and in particular to an integrated multi-axis force and torque sensor. Background Art

[0002] A multi-axis force and torque sensor is a sensor that can convert mechanical stresses applied in multiple directions into electrical signals, and is widely used in the fields of robots and drones.

[0003] Existing multi-axis force and torque sensors generally include a fixed box, an elastic body, a movable cover, and multiple strain gauges. The elastic body is suspended inside the fixed box, and the whole body of the elastic body is connected to the inside of the fixed box through multiple elastic beams. The movable cover is connected to the elastic body and floats on the mouth of the fixed box. The multiple strain gauges are dispersedly pasted on each elastic beam. When using the multi-axis force and torque sensor, the mechanical stress received by the movable cover will be transmitted to the elastic body and cause partial elastic beams on the whole body of the elastic body to undergo tensile, compressive, or bending deformations. The strain gauges attached to these elastic beams will also deform and change their own resistance values, so that the multi-axis force and torque sensor can measure the mechanical stress received by the movable cover.

[0004] However, in order to ensure that the strain gauges can correctly identify the deformations on each elastic beam, multiple strain gauges need to be attached to each elastic beam, resulting in a high production cost and a very complex production process for the multi-axis force and torque sensor.

[0005] In view of this, an integrated multi-axis force and torque sensor is needed. Summary of the Invention

[0006] In order to solve the problem that existing multi-axis force and torque sensors need to attach many strain gauges during production, resulting in high production costs and complex production processes, this application provides an integrated multi-axis force and torque sensor.

[0007] The integrated multi-axis force and torque sensor provided by this application adopts the following technical solutions: It includes a fixed box, an elastic component, a movable cover, a metal plate, and a measurement component. The elastic component is arranged inside the fixed box and connected to the inner wall of the fixed box;

[0008] The movable cover is arranged at the mouth of the fixed box and connected to the elastic component;

[0009] The metal plate is arranged between the elastic component and the inner bottom wall of the fixed box and connected to the elastic component;

[0010] The measurement component is arranged between the metal plate and the inner bottom wall of the fixed box and can detect the displacement or rotation of the metal plate.

[0011] By adopting the above technical solution, when the movable cover is subjected to mechanical stress, this part of the mechanical stress will be transmitted to the elastic component. When the elastic component bears the mechanical stress, it will deform and cause the metal plate connected to the elastic component to move or rotate, so as to convert the mechanical stress borne by the movable cover into the movement or rotation of the metal plate. At this time, the measuring component can detect the displacement or rotation of the metal plate and calculate the magnitude and direction of the mechanical stress according to the detection result, so that a large number of strain gauges do not need to be attached during the production of the integrated multi-axis force torque sensor, thus making the production cost of the integrated multi-axis force torque sensor relatively low and the production process relatively simple.

[0012] Specifically, the elastic component includes a gasket, a frame, an inner moving block and a plurality of elastic members. The gasket is abutted between the measuring component and the frame. The inner moving block is arranged inside the frame. The plurality of elastic members are arranged at intervals around the inner moving block. One end of each elastic member is connected to the inner moving block, and the other end of each elastic member is connected to the frame. An insertion through hole is formed on the inner moving block. An insertion block is arranged on the movable cover. An installation hole leading to the measuring component is formed on the gasket. The insertion block can be inserted into the insertion through hole and abutted against the inner wall of the insertion through hole. One end of the insertion block passes through the insertion through hole and is connected to the metal plate, so that the metal plate is suspended in the installation hole.

[0013] By adopting the above technical solution, when the movable cover is subjected to mechanical stress, it will drive the inner moving block and the metal plate to move together through the insertion block, and cause the elastic members around the moving block to deform; and the elastic members around the inner moving block will return to their original state after the mechanical stress applied to the movable cover disappears, and make the movable cover, the inner moving block and the metal plate return to their original positions together.

[0014] Further, the measuring component includes a measuring unit and a communication unit. The measuring unit includes a coil and an inductance measuring device. The coil is arranged below the metal plate. The inductance measuring device can detect the inductance of the coil;

[0015] The communication unit is electrically connected to the inductance measuring module and can transmit the measured inductance value to the host computer.

[0016] By adopting the above technical solution, when the metal plate moves, it will change the normal and tangential distances between the metal plate and the coil, and then cause the inductance of the coil to change. The inductance measuring device can detect the inductance of the coil and send the detection result to the host computer through the communication unit, so that the host computer can obtain the information of the mechanical stress through the change of the inductance value.

[0017] Further, the communication unit includes a circuit board and a transmission line. The circuit board is disposed between the gasket and the inner bottom wall of the fixed box. The coil and the inductance measuring device are both disposed on the circuit board. One end of the transmission line is connected to the circuit board, and the other end of the transmission line passes through a through hole formed in the box wall of the fixed box and extends outside the fixed box, and can be electrically connected to the host computer.

[0018] By adopting the above technical solution, the circuit board can be used to mount the coil and the inductance measuring device, and the detection result of the inductance measuring device can be transmitted to the host computer through the transmission line.

[0019] Further, a calibration component is further included. The calibration component includes a horizontal calibration unit and a moving unit. The horizontal calibration unit can apply a standard force in the horizontal direction to the inner moving block. The moving unit is in transmission connection with the horizontal calibration unit and can drive the horizontal calibration unit to rotate around the central axis of the inner moving block to change the direction of the standard force applied by the horizontal calibration unit.

[0020] By adopting the above technical solution, the horizontal calibration unit can apply a standard force in the horizontal direction to the inner moving block, and the moving unit can drive the horizontal calibration unit to rotate around the central axis of the inner moving block, so that the horizontal calibration unit can apply a standard force to the inner moving block in different horizontal directions, and then the user can calibrate the integrated multi-axis force torque sensor in the horizontal direction.

[0021] Further, the moving unit includes a sun gear, a planet gear and a rotating device. The sun gear is disposed in the mounting hole and located between the metal plate and the measuring component. The rotation axis of the sun gear coincides with the central axis of the inner moving block. An internal gear is provided on the inner wall of the mounting hole. The planet gear is disposed between the internal gear and the sun gear and meshes with both the internal gear and the sun gear at the same time. The rotating device is in transmission connection with the sun gear and can drive the sun gear to rotate;

[0022] The horizontal calibration unit includes a horizontal magnetic member and a horizontal terminal. The horizontal magnetic member and the horizontal terminal are both disposed on the side of the planet gear facing the inner moving block. At least two horizontal electromagnets are provided on the inner moving block. The horizontal electromagnets are spaced apart around the central axis of the inner moving block, and each horizontal electromagnet is in the same horizontal plane as the horizontal magnetic member. When the planet gear drives the horizontal magnetic member to move to a position close to any one of the horizontal electromagnets, the horizontal electromagnet can be electrically connected to the horizontal terminal and receive a standard force from the horizontal magnetic member.

[0023] By adopting the above technical solution, the rotating device can drive the sun wheel to rotate, so that the sun wheel can drive the planetary wheel to perform a planetary motion around the central axis of the inner moving block while revolving and rotating. When the planetary wheel drives the horizontal magnetic part thereon to move to a position close to any horizontal electromagnet at the bottom of the inner moving block, the horizontal electromagnet will be electrically connected to the horizontal terminal on the planetary wheel and generate a magnetic field that is the same or opposite to the magnetic pole of the horizontal magnetic part. Since each horizontal electromagnet is in the same horizontal plane as the horizontal magnetic part, the inner moving block will be subjected to a standard force in the horizontal direction.

[0024] Furthermore, the calibration assembly also includes a vertical calibration unit, which can apply a standard force along the vertical direction to the inner moving block.

[0025] By adopting the above technical solution, the vertical calibration unit can apply a standard force in the vertical direction to the inner moving block, so that the user can calibrate the integrated multi-axis force and torque sensor in the vertical direction.

[0026] Furthermore, the vertical calibration unit includes a vertical magnetic part and a vertical terminal, and the vertical magnetic part and the vertical terminal are both arranged on the side of the planetary wheel facing the inner moving block. The inner moving block is provided with a vertical electromagnet. When the planetary wheel drives the vertical magnetic part to move to directly below the vertical electromagnet, the vertical electromagnet can be electrically connected to the vertical terminal and be subjected to a standard force from the vertical magnetic part.

[0027] By adopting the above technical solution, when the planetary gear drives the vertical magnetic part to move to directly below the vertical electromagnet, the vertical electromagnet will be electrically connected to the vertical terminal and generate a magnetic field that is the same or opposite to the magnetic pole of the vertical magnetic part. Since the vertical electromagnet is located directly above the vertical magnetic part, the inner moving block will be subjected to a standard force in the vertical direction.

[0028] Furthermore, it also includes a dust-proof pad, which is arranged on the box opening of the fixed box, and the movable cover can abut against the dust-proof pad.

[0029] By adopting the above technical solution, the dust-proof pad can block the gap between the box opening of the fixed box and the movable cover, so that external dust is not easy to enter the interior of the fixed box through the gap.

[0030] Furthermore, a fixing screw hole is provided on the box opening of the fixing box, a connecting hole is provided on the dust-proof pad, and the dust-proof pad can be connected to the fixing box by passing a bolt through the connecting hole and being screwed to the fixing screw hole;

[0031] The movable cover is provided with a clearance hole matched with the bolt on the dust isolation pad, and the diameter of the screw head of the bolt is smaller than the hole diameter of the clearance hole.

[0032] By adopting the above technical solution, the dust-proof pad can be fixed on the box opening of the fixed box via bolts; the aperture of the clearance hole is set larger than the diameter of the bolt head so that the movable cover will not collide with the bolt when moving.

[0033] In summary, the present application includes at least one of the following beneficial technical effects:

[0034] 1. It includes a fixed box, an elastic component, a movable cover, a metal plate and a measuring component. The elastic component is arranged inside the fixed box and connected to the inner wall of the fixed box; the movable cover is arranged at the box mouth of the fixed box and connected to the elastic component; the metal plate is arranged between the elastic component and the inner bottom wall of the fixed box and connected to the elastic component; the measuring component is arranged between the metal plate and the inner bottom wall of the fixed box and can detect the displacement or rotation of the metal plate. When the movable cover is subjected to mechanical stress, this part of the mechanical stress will be transmitted to the elastic component, and the elastic component will deform when subjected to the mechanical stress and cause the metal plate connected to the elastic component to move or rotate, so that the mechanical stress borne by the movable cover can be converted into the movement or rotation of the metal plate. At this time, the measuring component can detect the displacement or rotation of the metal plate, and calculate the size and direction of the mechanical stress according to the detection result, so that the integrated multi-axis force torque sensor does not need to be attached with many strain gauges during production, thereby making the production cost of the integrated multi-axis force torque sensor low and the production process simpler;

[0035] 2. It also includes a calibration component, which includes a horizontal calibration unit, a moving unit and a vertical calibration unit. The horizontal calibration unit can apply a standard force along the horizontal direction to the inner moving block. The moving unit is transmission-connected to the horizontal calibration unit and can drive the horizontal calibration unit to rotate around the central axis of the inner moving block to change the direction of the standard force applied by the horizontal calibration unit, so that the horizontal calibration unit can apply a standard force to the inner moving block in different horizontal directions, thereby allowing the user to calibrate the integrated multi-axis force and torque sensor in the horizontal direction; the vertical calibration unit can apply a standard force along the vertical direction to the inner moving block, so that the user can calibrate the integrated multi-axis force and torque sensor in the vertical direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a stereogram of the integrated multi-axis force torque sensor of the present application;

[0037] Figure 2 is a top view of the integrated multi-axis force and torque sensor of the present application;

[0038] Figure 3 is along Figure 2 A schematic cross-sectional view taken along the AA direction;

[0039] Figure 4 is a schematic cross-sectional view taken along the Figure 2 B-B direction in;

[0040] Figure 5 is Figure 3 a schematic enlarged view of region C in, which shows an outer electric ring and an inner electric disk;

[0041] Figure 6 is taken along the Figure 3 D-D direction in.

[0042] Reference numerals: 1, fixed box; 2, elastic component; 21, gasket; 211, internal gear; 212, outer electric ring; 22, frame; 23, inner moving block; 231, horizontal electromagnet; 232, vertical electromagnet; 24, elastic member; 3, movable cover; 31, insertion block; 32, relief hole; 4, metal plate; 5, measurement component; 51, measurement unit; 511, coil; 52, communication unit; 521, circuit board; 522, transmission line; 6, calibration component; 61, horizontal calibration unit; 611, horizontal magnetic member; 612, horizontal terminal; 62, moving unit; 621, sun gear; 6211, inner electric disk; 622, planet gear; 623, rotating device; 63, vertical calibration unit; 631, vertical magnetic member; 632, vertical terminal; 7, dust-proof pad. Detailed implementation manners

[0043] The following will describe the present application in conjunction with the attached Figure 1 - attached Figure 6 drawings:

[0044] Referring to Figure 1 and Figure 2 , an integrated multi-axis force torque sensor includes: a fixed box 1, a measurement component 5, an elastic component 2, a movable cover 3, a metal plate 4, and a calibration component 6. The measurement component 5 includes a communication unit 52 and a measurement unit 51. The communication unit 52 includes a circuit board 521 and a transmission line 522. The circuit board 521 is disposed in the fixed box 1 and abuts against the bottom wall of the fixed box 1. One end of the transmission line 522 is connected to the circuit board 521, and the other end of the transmission line 522 passes through a through hole formed in the box wall of the fixed box 1 and extends outside the fixed box 1, and is disposed on a plug (not shown in the figure) for electrically connecting to an upper computer.

[0045] Referring to Figure 3 and Figure 6, the measuring unit 51 includes four coils 511 and an inductance measuring device (not shown in the figure). The four coils 511 are arranged in an array on the circuit board 521. The inductance measuring device is electrically connected to the four coils 511. The inductance measuring device can be a preamplifier in an eddy current displacement sensor. The preamplifier can detect the change in the inductance value of the coil 511 array, so that the inductance measuring device can form an eddy current displacement sensor with the four coils 511.

[0046] See Figure 3 and Figure 4 , the elastic component 2 includes a gasket 21, a frame 22, an inner moving block 23 and six elastic members 24. The gasket 21 is annular. The annular gasket 21 is arranged between the circuit board 521 and the frame 22. The inner ring of the annular gasket 21 forms a mounting hole. Four screw holes are equidistantly opened on the inner bottom wall of the fixed box 1 around its own central axis. Four through holes corresponding to these screw holes are provided on the frame 22, the gasket 21 and the circuit board 521. Bolts can sequentially pass through the through holes on the frame 22, the gasket 21 and the circuit board 521 and be screwed into the screw holes, so as to fix the frame 22, the gasket 21 and the circuit board 521 on the inner bottom wall of the fixed box 1; the inner moving block 23 is arranged inside the frame 22. The six elastic members 24 are arranged equidistantly around the inner moving block 23. One end of each elastic member 24 is connected to the inner moving block 23, and the other end of each elastic member 24 is connected to the frame 22. The elastic member 24 can be made of metal. When the inner moving block 23 moves or rotates in the x-axis, y-axis or z-axis direction, these elastic members 24 will deform and return the inner moving block 23 to its original position when the mechanical stress driving the inner moving block 23 to move disappears; a plugging through hole is opened in the middle of the inner moving block 23. The cross-section of the plugging through hole is square. A plugging block 31 adapted to the plugging through hole is provided on the bottom surface of the movable cover 3. The body of the plugging block 31 is inserted into the plugging through hole and abuts against the inner wall of the plugging through hole. The bottom end of the plugging block 31 passes through the plugging through hole and is connected to the metal plate 4, so that the metal plate 4 is suspended in the inner ring of the annular gasket 21. The metal plate 4 can be made of aluminum and is adhered to the plugging block 31 by glue.

[0047] See Figure 1 and Figure 5 , a circle of protrusions is provided at one end of the body of the plugging block 31 close to the movable cover 3. The protrusions can abut against the inner moving block 23 and form a circle of gaps between the bottom of the movable cover 3 and the box opening of the fixed box 1. The setting of the gaps not only enables the movable cover 3 to move back and forth with the inner moving block 23 and the metal plate 4 in the z-axis direction, but also can limit the maximum distance that the inner moving block 23 moves in the direction close to the bottom of the fixed box 1, that is, when the movable cover 3 abuts against the box opening of the fixed box 1, it cannot continue to move with the inner moving block 23 in the direction close to the bottom of the fixed box 1, so as to realize the overload protection of the elastic body around the inner moving block 23 in the z-axis direction.

[0048] Through the above arrangement, when the movable cover 3 is subjected to mechanical stress, this part of the mechanical stress will be transmitted to the inner movable block 23 and the metal plate 4, and the elastic member 24 around the inner movable block 23 will be deformed when subjected to the mechanical stress and cause the metal plate 4 to move or rotate, so as to be able to convert the mechanical stress borne by the movable cover 3 into the movement or rotation of the metal plate 4. At this time, the inductance measuring device and the coil 511 array can cooperate and detect the displacement or rotation of the metal plate 4, so that the host computer can calculate the size and direction of the mechanical stress according to the detection results, so that the integrated multi-axis force and torque sensor does not need to be attached with many strain gauges during production, thereby making the production cost of the integrated multi-axis force and torque sensor lower and the production process simpler.

[0049] Specifically, a dust-proof pad 7 can be provided at the box opening of the fixed box 1. The dust-proof pad 7 can be made of soft materials such as rubber. On the one hand, it can block a portion of the gap between the bottom of the movable cover 3 and the box opening of the fixed box 1, so that external dust is not easy to enter the interior of the fixed box 1 through the gap; on the other hand, the dust-proof pad 7 can be deformed when the movable cover 3 moves toward the box bottom of the fixed box 1, and will not restrict the movement of the movable cover 3 toward the box bottom of the fixed box 1; the box opening of the fixed box 1 is provided with fixing screw holes at equal intervals around its own central axis, and four connecting holes are provided on the dust-proof pad 7, so that the dust-proof pad 7 can be connected to the fixed box 1 by bolts passing through the connecting holes and the fixing screw holes; four clearance holes 32 are also provided on the movable cover 3 to match the bolts on the dust-proof pad 7, and the aperture of each clearance hole 32 is larger than the diameter of the screw head of the bolt on the dust-proof pad 7, so that the movable cover 3 will not collide with these bolts when moving.

[0050] See also Figure 4 and Figure 6 The calibration component 6 includes a moving unit 62, a horizontal calibration unit 61 and a vertical calibration unit 63. The moving unit 62 includes a sun gear 621, a pair of planetary gears 622 and a rotating device 623. The sun gear 621 is arranged in the inner ring of the annular gasket 21 and is located between the metal plate 4 and the measuring component 5. The rotating shaft of the sun gear 621 coincides with the central axis of the inner moving block 23. An internal gear 211 is provided on the inner ring wall of the annular gasket 21. Two planetary gears 622 are relatively arranged with the sun gear 621 as the center. Each planetary gear 622 is meshed with the internal gear 211 and the sun gear 621 at the same time. The rotating device 623 is a rotating motor, which is arranged on the circuit board 521. The driving shaft of the rotating motor is transmission-connected to the sun gear 621 and can drive the sun gear 621 to rotate.

[0051] See also Figure 4 and Figure 6, the diameter of the planetary gear 622 is set to be one-fourth of the inner ring diameter of the annular gasket 21. The horizontal calibration unit 61 includes a horizontal magnetic member 611 and a horizontal terminal 612. Both the horizontal magnetic member 611 and the horizontal terminal 612 are disposed on one side of a planetary gear 622 facing the inner moving block 23. A ring of convex rings is also provided on the wheel surface of the planetary gear 622. The gear surface of the planetary gear 622 is located below the convex ring. A conductive groove is circumferentially formed on the convex ring. An outer electric ring 212 is also provided on the inner ring wall of the annular gasket 21. An inner electric disk 6211 is provided at the top of the sun gear 621. Both the outer electric ring 212 and the inner electric disk 6211 are inserted into the conductive groove and abut against the inner wall of the conductive groove. In actual use, the outer electric ring 212 can be connected to the positive pole of the power supply and the inner electric disk 6211 can be connected to the negative pole of the power supply, or the outer electric ring 212 can be connected to the negative pole of the power supply and the inner electric disk 6211 can be connected to the positive pole of the power supply. In this way, it can not only supply power to the electrical equipment on the planetary gear 622 through the outer electric ring 212 and the inner electric disk 6211, but also prevent the planetary gear 622 from slipping off between the sun gear 621 and the internal gear 211.

[0052] See Figure 4 and Figure 6 , four horizontal electromagnets 231 are provided on the inner moving block 23. The four horizontal electromagnets 231 are equidistantly arranged around the central axis of the inner moving block 23. The connection line of two of the horizontal electromagnets 231 is arranged along the x-axis direction, and the connection line of the other two horizontal electromagnets 231 is arranged along the y-axis direction. The horizontal magnetic member 611 can be an electromagnet. The magnetic regions of each horizontal electromagnet 231 and the magnetic region of the horizontal magnetic member 611 are in the same horizontal plane. Since the diameter of the planetary gear 622 is set to be one-fourth of the inner ring diameter of the annular gasket 21, when the planetary gear 622 rotates one week around the sun gear 621, the magnetic region of the horizontal magnetic member 611 will sequentially pass in front of the magnetic regions of each horizontal electromagnet 231. When the planetary gear 622 drives the horizontal magnetic member 611 to move to a position close to any one of the horizontal electromagnets 231, the positive terminal and the negative terminal of this horizontal electromagnet 231 can abut against the horizontal terminal 612 on the planetary gear 622, so that the horizontal electromagnet 231 generates a magnetic field with the same or opposite magnetic poles as the horizontal magnetic member 611. Since each horizontal electromagnet 231 and the horizontal magnetic member 611 are in the same horizontal plane, the inner moving block 23 will be subjected to a standard force in the x-axis direction or the y-axis. The magnitude of this standard force can be specifically determined by setting the distance and magnetic magnitude between the magnetic region of the horizontal electromagnet 231 and the magnetic region of the horizontal magnetic member 611.

[0053] See Figure 4 and Figure 6, the vertical calibration unit 63 includes two vertical magnetic members 631 and two vertical terminals 632. On one side of each planet gear 622 facing the inner moving block 23, there is provided a vertical magnetic member 631 and a vertical terminal 632. Each vertical magnetic member 631 is arranged at the center of the planet gear 622. The vertical terminal 632 is in a ring structure, and the ring-shaped vertical terminal 632 surrounds the vertical magnetic member 631. The ring-shaped vertical terminal 632 is separated into two halves by an insulating material, one half is connected to the positive pole of the power supply, and the other half is connected to the negative pole of the power supply.

[0054] See Figure 4 and Figure 6 , the inner moving block 23 is provided with four vertical electromagnets 232. These four vertical electromagnets 232 are also arranged at equal intervals around the central axis of the inner moving block 23. Each vertical electromagnet 232 is located between two horizontal electromagnets 231. The vertical electromagnet 232 includes a columnar positive terminal and a negative terminal. The positive terminal and the negative terminal are oppositely arranged on both sides of the magnetic region of the vertical electromagnet 232. The positive terminals and negative terminals of adjacent two vertical electromagnets 232 are arranged in the opposite way; the vertical magnetic member 631 can be an electromagnet. When the planet gear 622 drives the two vertical magnetic members 631 to move to directly below a pair of vertical electromagnets 232, the positive terminal and the negative terminal of this pair of vertical electromagnets 232 will respectively abut against the two halves of the ring-shaped vertical terminal 632, so that these two vertical electromagnets 232 generate a magnetic field with the same or opposite magnetic poles as the vertical magnetic member 631, so that the inner moving block 23 will receive a standard force in the z-axis direction; when the planet gear 622 drives the two vertical magnetic members 631 to move to directly below another pair of vertical electromagnets 232, since the positive terminal and the negative terminal of this pair of vertical electromagnets 232 are arranged in the opposite way to the previous pair of vertical electromagnets 232, the direction of the standard force received by the inner moving block 23 in the z-axis direction at this time is also opposite, that is, one pair of vertical electromagnets 232 makes the inner moving block 23 move upward, and the other pair of vertical electromagnets 232 makes the inner moving block 23 move downward.

[0055] It should be noted that when the vertical electromagnet 232 generates a magnetic field with the same or opposite magnetic poles as the vertical magnetic member 631, the resultant moment of the force received by the inner moving block 23 is zero, so that the inner moving block 23 will only move in the z-axis direction and will not deflect, thus facilitating the calibration of the integrated multi-axis force torque sensor in the z-axis direction.

[0056] The calibration process of the integrated multi-axis force torque sensor provided by this application is as follows:

[0057] The user can start the rotating device 623 to drive the sun gear 621 to rotate, so that the sun gear 621 drives the planet gear 622 to rotate one week around the center of the sun gear 621. During the rotation process, the inner moving block 23 will be subjected to standard-sized tensile and thrust forces in the x-axis, y-axis, and z-axis directions and drive the metal plate 4 to move accordingly. Subsequently, the inductance measuring device and the coil 511 array can cooperate to detect the displacement of the metal plate 4, so that the host computer can calibrate the integrated multi-axis force torque sensor with reference to the displacement amount of the metal plate 4, the magnitude of the standard force, and the direction of the standard force.

[0058] The implementation principle of the integrated multi-axis force torque sensor described in this application is as follows:

[0059] When the movable cover 3 is subjected to mechanical stress, this part of the mechanical stress will be conducted to the inner moving block 23 and the metal plate 4. When the elastic member 24 around the inner moving block 23 bears the mechanical stress, it will deform and cause the metal plate 4 to move or rotate, so as to convert the mechanical stress borne by the movable cover 3 into the movement or rotation of the metal plate 4. At this time, the inductance measuring device and the coil 511 array can cooperate to detect the displacement or rotation of the metal plate 4, so that the host computer can calculate the magnitude and direction of the mechanical stress according to the detection results, so that the integrated multi-axis force torque sensor does not need to attach a lot of strain gauges during production, so that the production cost of the integrated multi-axis force torque sensor is relatively low and the production process is relatively simple.

[0060] The embodiments of this specific implementation manner are all preferred embodiments of this application, and do not limit the protection scope of this application accordingly. The same components are denoted by the same reference numerals. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. Integrated multi-axis force torque sensor, characterized by: It comprises a fixed box (1), an elastic component (2), a movable cover (3), a metal plate (4), a measuring component (5) and a calibration component (6), wherein the elastic component (2) is arranged inside the fixed box (1) and connected to the inner wall of the fixed box (1); The movable cover (3) is arranged at the box opening of the fixed box (1) and is connected to the elastic component (2); The elastic component (2) comprises a gasket (21), a frame (22), an inner moving block (23) and a plurality of elastic members (24); the gasket (21) is abutted between the measuring component (5) and the frame (22); the inner moving block (23) is arranged in the frame (22); a plurality of elastic members (24) are arranged at intervals around the inner moving block (23); one end of each elastic member (24) is connected to the inner moving block (23); the other end of each elastic member (24) is connected to the inner moving block (23); One end is connected to the frame (22), a plug-in through hole is provided on the inner movable block (23), a plug-in block (31) is provided on the movable cover (3), a mounting hole leading to the measuring component (5) is provided on the gasket (21), the plug-in block (31) can be inserted into the plug-in through hole and abut against the inner wall of the plug-in through hole, one end of the plug-in block (31) passes through the plug-in through hole and is connected to the metal plate (4) so ​​that the metal plate (4) is suspended in the mounting hole; The measuring component (5) is arranged between the metal plate (4) and the inner bottom wall of the fixing box (1) and is capable of detecting the displacement or rotation of the metal plate (4); The calibration component (6) comprises a horizontal calibration unit (61) and a moving unit (62); the horizontal calibration unit (61) is capable of applying a standard force along the horizontal direction to the inner moving block (23); the moving unit (62) is transmission-connected to the horizontal calibration unit (61) and is capable of driving the horizontal calibration unit (61) to rotate around the central axis of the inner moving block (23) to change the direction of the standard force applied by the horizontal calibration unit (61).

2. The integrated multi-axis force torque sensor according to claim 1, characterized in that: The measuring component (5) comprises a measuring unit (51) and a communication unit (52); the measuring unit (51) comprises a coil (511) and an inductance measuring device; the coil (511) is arranged below the metal plate (4); and the inductance measuring device is capable of detecting the inductance of the coil (511); The communication unit (52) is electrically connected to the inductance measurement module and is capable of transmitting the measured inductance value to a host computer.

3. The integrated multi-axis force torque sensor according to claim 2, characterized in that: The communication unit (52) comprises a circuit board (521) and a transmission line (522); the circuit board (521) is arranged between the gasket (21) and the inner bottom wall of the fixed box (1); the coil (511) and the inductance measuring device are both arranged on the circuit board (521); one end of the transmission line (522) is connected to the circuit board (521); the other end of the transmission line (522) passes through a through hole provided on the box wall of the fixed box (1) and extends out of the fixed box (1), and can be electrically connected to the host computer.

4. The integrated multi-axis force torque sensor according to claim 1, characterized in that: The moving unit (62) comprises a sun gear (621), a planetary gear (622) and a rotating device (623); the sun gear (621) is arranged in the mounting hole and between the metal plate (4) and the measuring assembly (5); the rotating shaft of the sun gear (621) coincides with the central axis of the inner moving block (23); an internal gear (211) is arranged on the inner wall of the mounting hole; the planetary gear (622) is arranged between the internal gear (211) and the sun gear (621) and meshes with the internal gear (211) and the sun gear (621) at the same time; the rotating device (623) is transmission-connected to the sun gear (621) and can drive the sun gear (621) to rotate; The horizontal calibration unit (61) comprises a horizontal magnetic part (611) and a horizontal terminal (612). The horizontal magnetic part (611) and the horizontal terminal (612) are both arranged on the side of the planetary gear (622) facing the inner moving block (23). At least two horizontal electromagnets (231) are arranged on the inner moving block (23). Each of the horizontal electromagnets (231) is arranged at intervals around the central axis of the inner moving block (23). Each of the horizontal electromagnets (231) is located in the same horizontal plane as the horizontal magnetic part (611). When the planetary gear (622) drives the horizontal magnetic part (611) to move to a position close to any of the horizontal electromagnets (231), the horizontal electromagnet (231) can be electrically connected to the horizontal terminal (612) and receive a standard force from the horizontal magnetic part (611).

5. The integrated multi-axis force torque sensor according to claim 4, characterized in that: The calibration component (6) further comprises a vertical calibration unit (63), wherein the vertical calibration unit (63) is capable of applying a standard force in a vertical direction to the inner moving block (23).

6. The integrated multi-axis force torque sensor according to claim 5, characterized in that: The vertical calibration unit (63) comprises a vertical magnetic part (631) and a vertical terminal (632). The vertical magnetic part (631) and the vertical terminal (632) are both arranged on the side of the planetary gear (622) facing the inner moving block (23). A vertical electromagnet (232) is arranged on the inner moving block (23). When the planetary gear (622) drives the vertical magnetic part (631) to move to the position directly below the vertical electromagnet (232), the vertical electromagnet (232) can be electrically connected to the vertical terminal (632) and receive a standard force from the vertical magnetic part (631).

7. The integrated multi-axis force torque sensor according to claim 1, characterized in that: It also comprises a dust-proof pad (7), wherein the dust-proof pad (7) is arranged on the box opening of the fixed box (1), and the movable cover (3) can abut against the dust-proof pad (7).

8. The integrated multi-axis force torque sensor according to claim 7, characterized in that: The box opening of the fixing box (1) is provided with a fixing screw hole, the dust-isolating pad (7) is provided with a connecting hole, and the dust-isolating pad (7) can be connected to the fixing box (1) by passing a bolt through the connecting hole and being screwed to the fixing screw hole; The movable cover (3) is provided with a clearance hole (32) adapted to the bolt on the dust isolation pad (7), and the diameter of the screw head of the bolt is smaller than the hole diameter of the clearance hole (32).

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