A three-way isotropic scanning probe head

Abstract

The application discloses a three-way isotropic scanning probe, which comprises a base capable of moving in X, Y and Z directions, a measuring ball, a probe moving frame, an X-direction deformation assembly, a Y-direction deformation assembly and a Z-direction deformation assembly; the measuring ball is connected with the probe moving frame through a measuring rod; the base is elastically connected with the probe moving frame through the X-direction deformation assembly, the Y-direction deformation assembly and the Z-direction deformation assembly which are connected in parallel with each other; when the probe is subjected to forces in the X, Y and Z directions, the forces are respectively recorded as Fx, Fy and Fz; Fx, Fy and Fz are respectively transmitted to the X-direction deformation assembly, the Y-direction deformation assembly and the Z-direction deformation assembly through the probe moving frame. The masses of the moving parts in the X, Y and Z directions of the three-way isotropic scanning probe are equal, the stiffnesses in the three directions are equal, the natural frequencies of the three directions of the probe are equal, and the static characteristics and the dynamic characteristics of the probe are three-way isotropic.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of precision measuring instrument, and particularly relates to a three-way isotropic scanning probe. BACKGROUND

[0002] As a precision sensor, the probe is a key component of a coordinate measuring machine, a gear measuring center and other measuring equipment, and directly affects the measurement accuracy, working performance, use efficiency and flexibility of the precision measuring instrument; from the perspective of mechanical structure, although the existing parallel three-dimensional structure has solved the problem of inconsistent mass M in the three directions of the serial structure, it still needs to be further improved in terms of torsion resistance; the problem of mutual difference in dynamic characteristics of the three directions in the measurement process of the three-dimensional scanning probe has not been solved. SUMMARY

[0003] The present application provides a three-way isotropic scanning probe, which realizes mutual decoupling through an elastic rod and a parallel spring sheet mechanism and a probe moving frame, so as to improve the mechanical precision of the probe system; the three-way isotropy of the three-dimensional scanning probe is realized by designing equal total stiffness in three directions, so as to improve the measurement accuracy and the dynamic performance of the probe.

[0004] Technical scheme: In order to achieve the above object, the three-way isotropic scanning probe comprises a base capable of moving in X, Y and Z directions, a measuring ball, a probe moving frame, an X-direction deformation assembly, a Y-direction deformation assembly and a Z-direction deformation assembly; the measuring ball is connected with the probe moving frame through a measuring rod; the base is elastically connected with the probe moving frame through the X-direction deformation assembly, the Y-direction deformation assembly and the Z-direction deformation assembly which are connected in parallel with each other; when the probe is subjected to forces in X, Y and Z directions, the forces are respectively recorded as Fx, Fy and Fz; Fx, Fy and Fz are respectively transmitted to the X-direction deformation assembly, the Y-direction deformation assembly and the Z-direction deformation assembly through the probe moving frame.

[0005] Further, the X-direction deformation assembly comprises an x fixed frame, an x hinge plate and an x spring sheet; the x hinge plate is connected with the probe moving frame through a group of x elastic rods; the plane of the x hinge plate is perpendicular to the Y direction, the plane of the x spring sheet is perpendicular to the X direction, the x hinge plate is hinged to one end of the x spring sheet, the other end of the x spring sheet is connected with the x fixed frame, the x elastic rods are parallel to the X direction, and the x fixed frame is fixed on the base.

[0006] Further, the Y-direction deformation assembly comprises a y fixed frame, a y hinge plate and a y spring sheet; the y hinge plate is connected with the probe moving frame through a group of y elastic rods; the plane of the y hinge plate is perpendicular to the Z direction, the plane of the y spring sheet is perpendicular to the Y direction, the y hinge plate is hinged to one end of the y spring sheet, the other end of the y spring sheet is connected with the y fixed frame, the y elastic rods are parallel to the Y direction, and the y fixed frame is fixed on the base.

[0007] Further, the Z-direction deformation assembly comprises a z fixed frame, a z hinge plate and a z spring leaf; the z hinge plate is connected with the probe motion frame through a group of z elastic rods; the plane where the z hinge plate is located is perpendicular to the X direction, the plane where the z spring leaf is located is perpendicular to the Z direction, the z hinge plate is hingedly connected with one end of the z spring leaf, the other end of the z spring leaf is connected with the z fixed frame, the z elastic rods are parallel to the Z direction, and the z fixed frame is fixed on the base.

[0008] Further, the Z-direction deformation assembly further comprises a Z-direction gravity balance spring, the upper end of the Z-direction gravity balance spring is fixedly connected with the base, and the lower end is connected with the z hinge plate through a connecting piece.

[0009] Further, the upward pulling force of the gravity balance spring on the z hinge plate is equal to the gravity of the z hinge plate.

[0010] Further, the x spring leaf has two pieces, the two pieces of x spring leaf are parallel to each other, the two pieces of x spring leaf, the x hinge plate and the x fixed frame form a parallelogram elastic hinge structure; the y spring leaf has two pieces, the two pieces of y spring leaf are parallel to each other, the two pieces of y spring leaf, the y hinge plate and the y fixed frame form a parallelogram elastic hinge structure; the z spring leaf has two pieces, the two pieces of z spring leaf are parallel to each other, and the two pieces of z spring leaf, the z hinge plate and the z fixed frame form a parallelogram elastic hinge structure.

[0011] Further, the x spring leaf, the y spring leaf and the z spring leaf are respectively provided with a linear displacement sensor.

[0012] Further, the mass Mx of all the X-direction moving parts, the mass My of all the Y-direction moving parts and the mass Mz of all the Z-direction moving parts are the same.

[0013] Further, the stiffness K 1x , K 1y and K 1z of the x elastic rod, the y elastic rod and the z elastic rod are the same; the stiffness K 2x and K 2y of the x spring leaf and the y spring leaf are the same; the combined stiffness K 2z of the z spring leaf and the gravity balance spring is the same as the stiffness K 2x and K 2y ; as a result, the X-direction stiffness Kx, the Y-direction stiffness Ky and the Z-direction stiffness Kz are all equal.

[0014] Further, the masses of the moving parts in the X, Y and Z directions of the three-dimensional scanning probe are equal, the stiffnesses in the three directions are equal, the natural frequencies of the probe in the three directions are equal, and the static characteristics and dynamic characteristics of the probe in the three directions are equal.

[0015] Beneficial Effects: The triaxial isotropic 3D scanning probe of this invention, when measuring in one direction, addresses mechanical coupling issues in other directions by decoupling them through two parallel springs, an elastic rod, and the probe's motion frame, thereby improving the mechanical accuracy of the probe system. The triaxial isotropy of the 3D scanning probe is achieved by designing equal total stiffness in all three directions; on one hand, the total mass M is the same in all three directions; on the other hand, the elastic restoring force F and total stiffness K are the same in all three directions under the action of the parallel springs, elastic rod, and spring, thus improving measurement accuracy and probe dynamic performance. The mechanical mechanism is compact, with a small spatial volume and high sensitivity, resulting in high measurement accuracy and improved measurement efficiency. Attached Figure Description

[0016] Appendix Figure 1 Overall view of the triaxial isotropic scanning probe Detailed Implementation

[0017] The invention will now be further described with reference to the accompanying drawings.

[0018] As attached Figure 1 As shown, a triaxial isotropic scanning probe includes a base capable of displacement in the X, Y, and Z directions, a probe ball 1, a probe motion frame 3, an X-direction deformation component, a Y-direction deformation component, and a Z-direction deformation component; the probe ball 1 is connected to the probe motion frame 3 via a probe rod 2; the base is elastically connected to the probe motion frame 3 via the X-direction deformation component, the Y-direction deformation component, and the Z-direction deformation component connected in parallel; when the probe is subjected to forces in the X, Y, and Z directions respectively, the forces subjected to the probe are denoted as Fx, Fy, and Fz respectively; Fx, Fy, and Fz are transmitted to the X-direction deformation component, the Y-direction deformation component, and the Z-direction deformation component respectively through the probe motion frame 3.

[0019] like Figure 1 As shown, the X-direction deformation assembly includes an X-fixed frame 71, an X-hinge plate 5, and an X-spring 6; the X-hinge plate 5 is connected to the probe motion frame 3 through a set of X-elastic rods 4; the plane of the X-hinge plate 5 is perpendicular to the Y-direction, the plane of the X-spring 6 is perpendicular to the X-direction, one end of the X-hinge plate 5 and the X-spring 6 are hinged, the other end of the X-spring 6 is connected to the X-fixed frame 71, the X-elastic rods 4 are parallel to the X-direction, and the X-fixed frame 71 is fixed on the base.

[0020] like Figure 1 As shown, the Y-direction deformation assembly includes a Y-fixed frame 72, a Y-hinge plate 14, and a Y-spring 13; the Y-hinge plate 14 is connected to the probe motion frame 3 through a set of Y-elastic rods 15; the plane of the Y-hinge plate 14 is perpendicular to the Z-direction, the plane of the Y-spring 13 is perpendicular to the Y-direction, one end of the Y-hinge plate 14 and the Y-spring 13 are hinged, the other end of the Y-spring 13 is connected to the Y-fixed frame 72, the Y-elastic rods 15 are parallel to the Y-direction, and the Y-fixed frame 72 is fixed on the base.

[0021] likeFigure 1 As shown, the Z-direction deformation assembly includes a Z-fixed frame 73, a Z-hinge plate 11, and a Z-spring 8; the Z-hinge plate 11 is connected to the probe motion frame 3 through a set of Z-elastic rods 12; the plane of the Z-hinge plate 11 is perpendicular to the X direction, the plane of the Z-spring 8 is perpendicular to the Z direction, one end of the Z-hinge plate 11 and the Z-spring 8 are hinged, the other end of the Z-spring 8 is connected to the Z-fixed frame 73, the Z-elastic rods 12 are parallel to the Z direction, and the Z-fixed frame 73 is fixed on the base.

[0022] The Z-direction deformation assembly also includes a Z-direction gravity balance spring 9, the upper end of which is fixedly connected to the base, and the lower end is connected to the Z-hinge plate 11 via a connector 10.

[0023] The upward pulling force of the gravity balance spring 9 on the z-hinge plate 11 is equal to the weight of the z-hinge plate 11.

[0024] like Figure 1 As shown, there are two x-springs 6, which are parallel to each other. The two x-springs 6, together with the x-hinge plate 5 and the x-fixed frame 71, form a parallelogram elastic hinge structure. There are two y-springs 13, which are parallel to each other. The two y-springs 13, together with the y-hinge plate 14 and the y-fixed frame 72, form a parallelogram elastic hinge structure. There are two z-springs 8, which are parallel to each other. The two z-springs 8, together with the z-hinge plate 11 and the z-fixed frame 73, form a parallelogram elastic hinge structure.

[0025] The X-shaped deformation assembly includes two X-spring plates 6. These two X-spring plates 6, together with the X-hinge plate 5 and the X-fixed frame 71, form a parallelogram-shaped elastic hinge structure. Within this parallelogram-shaped elastic hinge structure, only the two X-spring plates 6 can undergo elastic deformation. Simultaneously, under the constraint of this parallelogram-shaped elastic hinge structure, the two X-spring plates are not prone to torsional deformation. Due to the parallelogram-shaped elastic hinge structure, the X-spring plates 6 only undergo bending deformation when subjected to a force Fx in the X direction. When the probe is subjected to a force in the Y or Z direction, the X-spring plate 6 will not bend. Spring 6 will not undergo torsional deformation; similarly, when moving in the X direction, the two x springs 6 will undergo bending deformation; at this time, because the Y deformation assembly also has a parallelogram elastic hinge structure composed of two y springs 13, y hinge plate 14 and y fixing frame 72, and the Z deformation assembly also has a parallelogram elastic hinge structure composed of two z springs 8, z hinge plate 11 and z fixing frame 73; therefore, when the two x springs 6 undergo bending deformation, the two y springs 13 and two z springs 8 in the Y deformation assembly and the Z deformation assembly will not undergo torsional deformation.

[0026] The torsional parallelogram elastic hinge structures and elastic rods in the X-axis, Y-axis, and Z-axis deformation components cooperate with each other to achieve mutual decoupling of the X-axis, Y-axis, and Z-axis deformation components.

[0027] Each of the x-spring 6, y-spring 13, and z-spring 8 is respectively equipped with a linear displacement sensor or a deformation sensor. The function of the linear displacement sensor is to convert the deformation or displacement of the spring into an electrical signal, thereby identifying the bending deformation of the spring.

[0028] The masses Mx of all moving parts in the X direction, My of all moving parts in the Y direction, and Mz of all moving parts in the Z direction are the same.

[0029] The mass Mx of all moving parts in the X direction and the mass My of all moving parts in the Y direction are each composed of the same mass x-hinge plate 5 and y-hinge plate 14, x-spring 6 and y-spring 13, x-fixed frame 71 and y-fixed frame 72, and x-elastic rod 4 and y-elastic rod 15. Therefore, the mass Mx of all moving parts in the X direction is the same as the mass My of all moving parts in the Y direction. The mass Mz of all moving parts in the Z direction is also composed of z-hinge plate 11, z-spring 8, z-fixed frame 73, and z-elastic rod 12; however, since the Z-deformation component has a static self-weight, a gravity balance spring 9 is used to make the mass Mx of all moving parts in the X direction, the mass My of all moving parts in the Y direction, and the mass Mz of all moving parts in the Z direction the same.

[0030] The stiffness K of the x-elastic rod 4, y-elastic rod 15 and z-elastic rod 12 1x K 1y and K 1z Same; the stiffness K of the x-spring 6 and y-spring 13 2x and K 2y Same; the combined stiffness K of the z-spring 8 and the gravity balance spring 9 is the same. 2z , and stiffness K 2x K 2y The results are the same; the stiffness in the X direction (Kx), Y direction (Ky), and Z direction (Kz) are all equal.

[0031] The x-spring 6 and y-spring 13 have the same working length, as do the x-elastic rod 4 and y-elastic rod 15; the z-spring 8 has a slightly longer working length than the z-spring 8 and y-spring 13.

[0032] The reeds in the scanning probe are usually made of common metal materials, including stainless steel, nickel alloys, and copper alloys.

[0033] Elastic rods are usually made of highly elastic materials, such as beryllium copper and stainless steel, which have good fatigue resistance and corrosion resistance.

[0034] The function of the elastic rod is to increase the accuracy and stability of the measurement, and at the same time, it can absorb vibrations and shocks caused by environmental factors or other factors, protecting the measuring element from damage.

[0035] The moving parts of the three-dimensional scanning probe have equal masses and equal stiffness in the X, Y, and Z directions, resulting in equal natural frequencies in the three directions, thus achieving isotropic static and dynamic characteristics of the probe.

[0036] A working method for measurement using a three-dimensional isotropic scanning probe.

[0037] When measuring the X direction, when the scanning probe moves in the X direction and the measuring ball 1 touches the object, the scanning probe is subjected to a force Fx in the X direction. Fx is transmitted synchronously to the probe motion frame 3 through the measuring rod 2. Fx acts on the x elastic rod 4 connected to the probe motion frame 3, and the x elastic rod 4 undergoes elastic deformation to generate elastic force. The elastic force acts on the x hinge plate 5 connected to it, and the x hinge plate 5 moves in the X direction due to the elastic force, causing the x spring 6 to deform. A linear displacement sensor is set on the x spring 6. The linear displacement sensor detects the deformation, transmits and analyzes the deformation, and completes the measurement in the X direction.

[0038] When measuring in the Y direction, when the scanning probe moves in the Y direction and the measuring ball 1 touches the object, the scanning probe is subjected to a force Fy in the Y direction. Fy is transmitted synchronously to the probe motion frame 3 through the measuring rod 2. Fy acts on the Y elastic rod 15 connected to the probe motion frame 3, and the Y elastic rod 15 undergoes elastic deformation to generate elastic force. The elastic force acts on the Y hinge plate 14 connected to it. The Y hinge plate 14 moves in the Y direction due to the elastic force, which drives the Y spring 13 to deform. A linear displacement sensor is set on the Y spring 13. The linear displacement sensor detects the deformation, transmits and analyzes the deformation, and completes the measurement in the Y direction.

[0039] When measuring in the Z direction, when the scanning probe moves in the Z direction and the measuring ball 1 touches the object, the scanning probe is subjected to a force Fz in the Z direction. Fz is transmitted synchronously to the probe motion frame 3 through the measuring rod 2. Fz acts on the z elastic rod 12 connected to the probe motion frame 3. The z elastic rod 12 undergoes elastic deformation and generates elastic force. The elastic force acts on the z hinge plate 11 connected to it. The z hinge plate 11 moves in the Z direction due to the elastic force, which drives the z spring 8 to deform. A linear displacement sensor is set on the z spring 8. The linear displacement sensor detects the deformation, transmits and analyzes the deformation, and completes the measurement in the Z direction.

[0040] During the measurement process, when the X-deformation component is subjected to force Fx, the x-elastic rod 4 generates an elastic force due to Fx, which in turn drives the x-hinge plate 5 to move in the X direction. At this time, the y-elastic rod 15 and z-elastic rod 12 are not affected by Fx due to their unique elastic properties, and therefore the y-spring and z-spring will not deform. Similarly, when the Y-deformation component is subjected to force Fy and the Z-deformation component is subjected to force Fz, the other two deformation components will not be affected.

[0041] The above are the preferred embodiments described in this invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention.

Claims

1. A triaxial isotropic scanning probe, characterized in that: The device includes a base capable of displacement in the X, Y, and Z directions, a measuring ball (1), a probe motion frame (3), an X-direction deformation component, a Y-direction deformation component, and a Z-direction deformation component; the measuring ball (1) is connected to the probe motion frame (3) via a measuring rod (2); the base is elastically connected to the probe motion frame (3) via the X-direction deformation component, the Y-direction deformation component, and the Z-direction deformation component connected in parallel; when the probe is subjected to forces in the X, Y, and Z directions respectively, the forces subjected to the probe are denoted as Fx, Fy, and Fz respectively; Fx, Fy, and Fz are transmitted to the X-direction deformation component, the Y-direction deformation component, and the Z-direction deformation component respectively through the probe motion frame (3); The X-direction deformation assembly includes an X-fixed frame (71), an X-hinge plate (5), and an X-spring (6); the X-hinge plate (5) is connected to the probe motion frame (3) through a set of X-elastic rods (4); the plane of the X-hinge plate (5) is perpendicular to the Y direction, the plane of the X-spring (6) is perpendicular to the X direction, one end of the X-hinge plate (5) and the X-spring (6) are hinged, the other end of the X-spring (6) is connected to the X-fixed frame (71), the X-elastic rods (4) are parallel to the X direction, and the X-fixed frame (71) is fixed on the base; The Y-direction deformation component includes a Y-fixed frame (72), a Y-hinge plate (14), and a Y-spring (13); the Y-hinge plate (14) is connected to the probe motion frame (3) through a set of Y-elastic rods (15); the surface of the Y-hinge plate (14) is perpendicular to the Z-direction, the surface of the Y-spring (13) is perpendicular to the Y-direction, one end of the Y-hinge plate (14) and the Y-spring (13) are hinged, the other end of the Y-spring (13) is connected to the Y-fixed frame (72), the Y-elastic rods (15) are parallel to the Y-direction, and the Y-fixed frame (72) is fixed on the base; The Z-direction deformation assembly includes a z-fixed frame (73), a z-hinge plate (11), and a z-spring (8); the z-hinge plate (11) is connected to the probe motion frame (3) through a set of z-elastic rods (12); the plane of the z-hinge plate (11) is perpendicular to the X direction, the plane of the z-spring (8) is perpendicular to the Z direction, one end of the z-hinge plate (11) and the z-spring (8) are hinged, the other end of the z-spring (8) is connected to the z-fixed frame (73), the z-elastic rods (12) are parallel to the Z direction, and the z-fixed frame (73) is fixed on the base.

2. The triaxial isotropic scanning probe according to claim 1, characterized in that: The Z-direction deformation assembly also includes a Z-direction gravity balance spring (9), the upper end of which is fixedly connected to the base, and the lower end is connected to the Z-hinge plate (11) through a connector (10).

3. A triaxial isotropic scanning probe according to claim 2, characterized in that: The upward pulling force of the gravity balance spring (9) on the z-hinge plate (11) is equal to the gravity of the z-hinge plate (11).

4. A triaxial isotropic scanning probe according to claim 1, characterized in that: There are two x-springs (6), which are parallel to each other. The two x-springs (6), together with the x-hinge plate (5) and the x-fixed frame (71), form a parallelogram elastic hinge structure. There are two y-springs (13), which are parallel to each other. The two y-springs (13), together with the y-hinge plate (14) and the y-fixed frame (72), form a parallelogram elastic hinge structure. There are two z-springs (8), which are parallel to each other. The two z-springs (8), together with the z-hinge plate (11) and the z-fixed frame (73), form a parallelogram elastic hinge structure.

5. A triaxial isotropic scanning probe according to claim 4, characterized in that: The x-spring (6), y-spring (13) and z-spring (8) are each respectively equipped with a linear displacement sensor.

6. A triaxial isotropic scanning probe according to claim 1, characterized in that: The masses Mx of all moving parts in the X direction, My of all moving parts in the Y direction, and Mz of all moving parts in the Z direction are the same.

7. A triaxial isotropic scanning probe according to claim 1, characterized in that: The stiffness K of the x-elastic rod (4), y-elastic rod (15) and z-elastic rod (12) 1x K 1y and K 1z Same; the stiffness K of the x-spring (6) and y-spring (13) 2x and K 2y Same; the combined stiffness K of the z-spring (8) and the gravity balance spring (9) 2z， With stiffness K 2x K 2y The results are the same; the stiffness in the X direction (Kx), Y direction (Ky), and Z direction (Kz) are all equal.

8. A triaxial isotropic scanning probe according to claim 7, characterized in that: The moving parts of the triaxial isotropic scanning probe have equal masses and equal stiffness in the X, Y, and Z directions, resulting in equal natural frequencies in the three directions, thus achieving triaxial isotropy in both static and dynamic characteristics.

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