Electromagnetic chuck of scanning probe

Abstract

The embodiment of the utility model provides an electromagnetic chuck for a scanning probe, and the chuck comprises a pedestal which comprises a mounting hole; the actuating device is arranged in the mounting hole and comprises a voice coil motor formed by a magnet cup and a moving coil, the magnet cup comprises a central magnet, an outer ring part and a containing cavity, and the moving coil is located in the containing cavity and configured to move in the axis direction of the central magnet; the magnetic suction coil is arranged on the moving coil, the magnetic suction coil is a planar coil and comprises a magnetic suction surface, the magnetic suction surface is perpendicular to the axis of the central magnet and is used for magnetically sucking the probe assembly, and the central magnet of the magnet cup serves as a permanent magnet, can temporarily fix the probe assembly and serves as a part of the voice coil motor at the same time; when separation is needed, the moving coil can drive the magnetic attraction coil to be far away from the probe assembly so as to achieve better separation, and the magnetic attraction coil can be driven by the moving coil to be far away from the probe assembly so as to be attached to the probe assembly.

Description

TECHNICAL FIELD

[0001] The utility model relates to a measuring head, especially a measuring head applied to a three-coordinate measuring machine. BACKGROUND

[0002] The three-coordinate measuring machine is an instrument capable of realizing measuring capabilities such as geometric shape, length, and circular division within a six-faced space, and its measuring functions include dimensional accuracy, positioning accuracy, geometric accuracy, and profile accuracy, and it is widely used in the mold, aviation, automobile, and electronic industries.

[0003] Generally, the three-coordinate measuring machine needs to be configured with a measuring head to accurately give a trigger signal through the measuring head. In order to adapt to different types of measuring needle assemblies and quickly replace the measuring needle assemblies, an electromagnetic chuck is usually configured, that is, the measuring needle assembly is fixed through the electromagnetic chuck. The conventional electromagnetic chuck usually includes a permanent magnet and an electromagnet, which temporarily fixes the measuring needle assembly through the permanent magnet, and reinforces through the electromagnet to prevent the measuring needle assembly from falling unexpectedly during testing. Although the permanent magnet is arranged in the middle of the chuck, the measuring needle assembly can be temporarily fixed easily, but when the measuring needle assembly needs to be replaced frequently, such as in a fast scanning measuring head, the permanent magnet still has a large holding force, making it difficult to separate and switch.

[0004] Therefore, a new technical solution is needed to solve the above technical problems. INVENTION CONTENTS

[0005] Therefore, the utility model provides a measuring head to solve the above technical problems.

[0006] A scanning measuring head electromagnetic chuck, comprising:

[0007] A base including a mounting hole;

[0008] An actuator device arranged in the mounting hole, including a voice coil motor formed by a magnet cup and a moving coil, the magnet cup including a center magnet, an outer ring portion surrounding the periphery of the center magnet, and a receiving cavity between the center magnet and the outer ring portion, the moving coil being located in the receiving cavity and being configured to move along the axis of the center magnet;

[0009] A magnetic attraction coil arranged on the moving coil, the magnetic attraction coil being a planar coil including a magnetic attraction surface, the magnetic attraction surface being perpendicular to the axis of the center magnet, and being used for magnetically attracting the measuring needle assembly.

[0010] The receiving cavity includes an upper cavity and a lower cavity, and a plurality of gap magnetic blocks are arranged in the lower cavity, the lower cavity includes a supporting surface, the supporting surface is in the form of a circular ring, and the plurality of gap magnetic blocks are arranged in the form of a circular array on the supporting surface.

[0011] The magnetic pole direction of the gap magnetic block passes through the central magnet axis, and the N poles of the gap magnetic blocks are all directed to the central magnet axis or all directed away from the central magnet axis.

[0012] The projection of each gap magnetic block on the placement surface is a sector.

[0013] The actuating device further comprises an actuating disc, the magnetic attraction coil is stacked on the actuating disc, and the actuating disc is fixed on the moving coil.

[0014] An inner ring part is arranged below the central magnet, a connecting part connects the outer ring part and the inner ring part, the outer ring part, the central magnet, the inner ring part and the connecting part form a containing cavity, and the inner ring part, the outer ring part and the connecting part form a soft magnet.

[0015] The base comprises a base part with an attached surface, the N pole of the central magnet is directed to the attached surface, and the N pole of each gap magnetic block is directed to the central magnet axis.

[0016] The base further comprises at least three protruding parts radially extending outward from the base part, each protruding part is provided with a positioning assembly, the positioning assembly is a pair of spaced positioning balls, and the pair of positioning balls have the same shape.

[0017] The actuating device further comprises a guide column, the guide column comprises a guide section and a positioning section, the guide section is a frustum, and the positioning section is a cylinder.

[0018] The mounting hole further comprises a limiting part extending from the mounting hole sidewall to the mounting hole middle part, and the bottom surface of the actuating device abuts against the limiting part.

[0019] Beneficial effects: the utility model discloses a scanning probe electromagnetic chuck, comprising: base, including mounting hole;Actuator, set up in mounting hole, including the voice coil motor formed by magnet cup and moving coil, the magnet cup includes center magnet, the outer ring portion of surrounding center magnet periphery and the accommodation cavity between center magnet and outer ring portion, the moving coil is located in the accommodation cavity, and be configured as along center magnet axis direction movement;Magnetic attraction coil, set up on the moving coil, the magnetic attraction coil is plane coil, including a magnetic attraction surface, the magnetic attraction surface is perpendicular to center magnet axis, for magnetic attraction probe assembly, the center magnet of magnet cup is as permanent magnet one aspect can provide temporary fixation to probe assembly, simultaneously as the part of voice coil motor, make moving coil can act to make magnetic attraction coil move to probe assembly and attach probe assembly to form more stable magnetic attraction connection, to make scanning probe electromagnetic chuck can stably form fixation to probe assembly, when needing to separate, moving coil can drive magnetic attraction coil and move away from probe assembly to realize better separation. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The utility model embodiment's scanning probe electromagnetic chuck three -dimensional schematic diagram;

[0021] Figure 2 For Figure 1 Front view;

[0022] Figure 3 For Figure 2 Middle A-A cross section schematic diagram;

[0023] Figure 4 For magnet cup and gap magnetic block arrangement schematic diagram;

[0024] Figure 5 For Figure 3 Left side portion magnetic induction line distribution schematic diagram;

[0025] Figure 6 For scanning probe electromagnetic chuck connection probe assembly schematic diagram.

[0026] Illustrate element explanation:

[0027] Base 10;Protruding portion 11;Positioning ball 12;Limiting portion 13;Actuator 20;Magnet cup 21;Center magnet 211;Connection portion 212;Outer ring portion 213;Inner ring portion 214;Accommodation cavity 215;Upper cavity 2151;Lower cavity 2152;Actuator cylinder 22;First coil 23;Actuator disc 24;Lower magnet 25;Gap magnetic block 251;Mounting disc 252;Magnetic attraction coil 31;Guide column 41;Guide section 411;Positioning section 412;Scanning probe electromagnetic chuck 500;Probe assembly 600. DETAILED DESCRIPTION

[0028] For the purpose, technical scheme and effect of the present application to be clearer and more explicit, the embodiments of the technical scheme of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to illustrate the technical scheme of the present application more clearly, thus only serve as examples, and cannot limit the protection scope of the present application.

[0029] Please refer to the accompanying Figures 1-6 The utility model discloses a kind of scanning probe electromagnetic chuck 500, it is usually arranged on the probe of three coordinate measuring machine, especially on scanning probe, for fixed probe needle assembly 600, the scanning probe electromagnetic chuck 500 includes base 10, actuator 20 and magnetic attraction coil 31.

[0030] The base 10 is used to be connected with probe and is positioned for probe needle assembly 600, in the embodiment, the base 10 includes the base body portion with the attached surface and at least three protruding parts 11 outwardly extending from the base body portion in a radial manner, positioning assembly is arranged on the protruding part 11, for positioning probe needle assembly 600 connected to electromagnetic chuck.

[0031] More specifically, a positioning assembly is arranged on each protruding part 11, the positioning assembly in the embodiment is a pair of interval positioning balls 12, the pair of positioning balls 12 has same form, the same form is that the material, radius, surface roughness of positioning ball 12 are same.The protruding part 11 includes positioning hole, the positioning ball 12 is contained in the positioning hole, so that the positioning ball 12 has first exposed part, it can be understood that the first exposed part of each positioning ball 12 is same.In addition, the interval between the pair of positioning balls 12 in each positioning assembly should be same, at the same time, when the base 10 includes a central axis, the interval between each positioning ball 12 and the central axis is equal.

[0032] In a specific embodiment, the probe needle assembly 600 includes a positioning column matched with the positioning ball 12, the positioning column has a second exposed part, the second exposed part is arc-shaped, and the whole is a cylindrical arch type, when the probe needle assembly 600 is connected to the electromagnetic chuck in the form of facing the attached surface, the second exposed part will be clamped between the pair of positioning balls 12, the arc surface point contact formed by the positioning ball 12 and the positioning column makes the probe needle assembly 600 be accurately positioned to the predetermined position.

[0033] The base 10 includes mounting hole, the actuator 20 is arranged in mounting hole, in the embodiment, the mounting hole also includes limiting portion 13 outwardly extending from mounting hole side wall to mounting hole middle part, the bottom surface of actuator 20 abuts the upper side of limiting portion 13, so that actuator 20 is limited by the limiting portion 13 in the axial direction of mounting hole.

[0034] The actuator 20 comprises a voice coil motor formed by the magnet cup 21 and the moving coil, the magnet cup 21 comprises a center magnet 211, an outer ring 213 surrounding the periphery of the center magnet 211, and a receiving cavity 215 between the center magnet 211 and the outer ring 213, the moving coil is located in the receiving cavity 215 and is configured to move along the axis direction of the center magnet 211.

[0035] Specifically, the center magnet 211 is in a cylindrical shape, the axis of the center magnet 211 is the axis of the cylinder, and the magnetic pole direction is parallel to the axis of the center magnet 211. In this embodiment, the N level of the center magnet 211 faces the attachment surface, and the S level faces away from the attachment surface.

[0036] The outer ring 213 surrounds the outside of the center magnet 211, and an inner ring 214 is arranged below the center magnet 211. A connecting part 212 connects the outer ring 213 and the inner ring 214. The outer ring 213, the center magnet 211, the inner ring 214, and the connecting part 212 form a ring-shaped receiving cavity 215, and the cross section of the entire magnet cup 21 is in the shape of "E". It can be understood that the inner ring 214, the outer ring 213, and the connecting part 212 are made of soft magnetic material and form soft magnets. In a specific embodiment, the inner ring 214, the outer ring 213, and the connecting part 212 are made of silicon steel.

[0037] In this embodiment, the receiving cavity 215 comprises an upper cavity 2151 adjacent to the attachment surface and a lower cavity 2152 adjacent to the connecting part 212 and away from the attachment surface. The moving coil is arranged in the upper cavity 2151 and is configured to move along the axis direction of the center magnet 211. More specifically, the moving coil comprises an actuator cylinder 22 sleeved on the center magnet 211 and a first coil 23 wound on the actuator cylinder 22. When current is passed through the first coil 23, according to the left-hand rule, the magnetic field formed by the first coil 23 has the same magnetic pole direction along the axis direction of the center magnet 211. By passing current in different directions, the magnetic pole direction of the magnetic field formed by the first coil 23 is the same as or opposite to the magnetic pole direction of the center magnet 211. The size of the current passed controls the magnetic force between the first coil 23 and the center magnet 211, that is, a voice coil motor structure is formed by the magnet cup 21 and the moving coil.

[0038] The magnetic attraction coil 31 is used to generate magnetic force to attract the measuring needle assembly 600. The magnetic attraction coil 31 is a planar coil, which includes a magnetic attraction surface. The magnetic attraction surface is perpendicular to the axis of the central magnet 211. According to the left-hand rule, the magnetic pole direction of the magnetic attraction coil 31 is parallel to the axis direction of the central magnet 211. The magnetic attraction coil 31 is arranged on the moving coil and moves together with the moving coil. When the moving coil moves along the axis direction of the central magnet 211, the magnetic attraction coil 31 also moves along the axis direction of the central magnet 211. More specifically, when the measuring needle assembly 600 contacts the attachment surface, the moving coil moves along the axis direction of the central magnet 211 towards the measuring needle assembly 600, and the magnetic attraction coil 31 is adjacent to the measuring needle assembly 600 and attracts the measuring needle assembly 600. It can be understood that the measuring needle assembly 600 includes a magnetizable component adjacent to the magnetic attraction coil 31, so that the magnetizable component is attracted by the magnetic field generated by the magnetic attraction coil 31.

[0039] Further, the actuating device 20 further includes an actuating disc 24. The magnetic attraction coil 31 is arranged on the actuating disc 24, and the actuating disc 24 is fixed on the moving coil. On the one hand, the actuating disc 24 keeps the magnetic attraction coil 31 in the form of a planar coil. On the other hand, the actuating disc 24 keeps the magnetic attraction coil 31 stable during the operation. It can be understood that at least a part of the actuating disc 24 is attached to the actuating cylinder 22, and the actuating disc 24 is coaxially arranged with the actuating cylinder 22.

[0040] Further, the actuating device 20 further includes a guide column 41, which is used to make the measuring needle assembly 600 more stably enter the predetermined position and form an integral body after being attracted by the magnetic attraction coil 31. The guide column 41 can be fixed or movable. When the guide column 41 is fixed, the guide column 41 is fixed on the central magnet 211. When the guide column 41 is movable, the guide column 41 is fixed on the actuating disc 24. The guide column 41 includes a guide segment 411 and a positioning segment 412. The guide segment 411 is in the form of a truncated cone. The measuring needle assembly 600 includes a guide hole. When the guide segment 411 is inserted into the guide hole, the guide hole is guided into the positioning segment 412 through the form of the truncated cone, and matches with the positioning segment 412. The position of the measuring needle assembly 600 is accurately positioned by the positioning ball 12.

[0041] It can be understood that the positioning segment 412 is in the form of a cylinder.

[0042] Further, a plurality of gap magnetic blocks 251 are arranged in the lower cavity 2152. The lower cavity 2152 includes a supporting surface. It can be understood that the supporting surface is in the form of a ring. The gap magnetic blocks 251 are arranged on the supporting surface in the form of a circumferential array.

[0043] Further, the projection of each gap magnetic block 251 on the placement surface is a sector.

[0044] Further, the magnetic pole direction of the gap magnetic block 251 passes through the axis of the center magnet 211, and the N pole of each gap magnetic block 251 faces the axis of the center magnet 211 or faces away from the axis of the center magnet 211.

[0045] It can be understood that the N pole of each gap magnetic block 251 should be arranged adjacent to the S pole of the center magnetic block or the S pole should be arranged adjacent to the N pole of the center magnetic block, so that the entire magnet cup 21 has more stable magnetic flux and reduces the magnetic resistance. In the embodiment, the N pole of each gap magnetic block 251 faces the axis of the center magnet 211, and the S pole faces away from the axis of the center magnet 211.

[0046] In addition, it can be seen that the center magnet 211 of the magnet cup 21 as a permanent magnet can provide temporary fixation to the probe assembly 600 on the one hand, and as part of the voice coil motor, the moving coil can move so that the magnetic attraction coil 31 moves to the probe assembly 600 and adheres to the probe assembly 600 to form a more stable magnetic attraction connection, so that the scanning probe electromagnetic chuck 500 can stably fix the probe assembly 600. When separation is required, the moving coil can drive the magnetic attraction coil 31 away from the probe assembly 600 to achieve better separation.

[0047] Further, a mounting disc 252 is arranged on the lower side of the gap magnetic block 251, the mounting disc 252 is a disc with a central hole, and the gap magnetic block 251 is fixedly arranged on the mounting disc 252 so that each gap magnetic block 251 and the mounting disc 252 form an integral whole, which can be the lower magnet 25. Through this form, the installation is easier.

[0048] The above only describes the embodiments of the present application, and does not limit the patent range of the present application, and any equivalent structure or equivalent process transformation according to the content of the present application specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection range of the present application.

Claims

1. A scanning probe electromagnetic chuck, characterized by, The utility model relates to a magnetic needle assembly, comprising: a base comprising a mounting hole; an actuating device arranged in the mounting hole, comprising a voice coil motor formed by a magnet cup and a moving coil, the magnet cup comprising a central magnet, an outer ring portion surrounding the periphery of the central magnet, and a receiving cavity between the central magnet and the outer ring portion, the moving coil being arranged in the receiving cavity and configured to move along the axis of the central magnet; a magnetic attraction coil arranged on the moving coil, the magnetic attraction coil being a planar coil comprising a magnetic attraction surface perpendicular to the axis of the central magnet for magnetically attracting the magnetic needle assembly.

2. The scanning probe electromagnetic chuck of claim 1 wherein, The receiving cavity comprises an upper cavity and a lower cavity, and a plurality of gap magnets are arranged in the lower cavity, the lower cavity comprising a supporting surface in the form of a circular ring, and the plurality of gap magnets being arranged in a circumferential array on the supporting surface.

3. The scanning probe electromagnetic chuck of claim 2 wherein, The magnetic poles of the gap magnets are arranged along the axis of the central magnet, and the N poles of the gap magnets are arranged to face or be away from the axis of the central magnet.

4. The scanning probe electromagnetic chuck of claim 2 wherein, The projections of the gap magnets on the supporting surface are in the form of a sector.

5. The scanning probe electromagnetic chuck of claim 2 wherein, The actuating device further comprises an actuating disc, the magnetic attraction coil being arranged on the actuating disc, and the actuating disc being fixed to the moving coil.

6. The scanning probe electromagnetic chuck of claim 5 wherein, An inner ring portion is arranged below the central magnet, and a connecting portion connects the outer ring portion and the inner ring portion, the outer ring portion, the central magnet, the inner ring portion, and the connecting portion forming the receiving cavity, and the inner ring portion, the outer ring portion, and the connecting portion forming a soft magnet.

7. The scanning probe electromagnetic chuck of claim 6 wherein, The base comprises a base portion having an attachment surface, the N pole of the central magnet facing the direction of the attachment surface, and the N poles of the gap magnets facing the axis of the central magnet.

8. The scanning probe electromagnetic chuck of claim 7 wherein, The base further comprises at least three protruding portions extending radially outward from the base portion, each protruding portion comprising a positioning assembly, the positioning assembly comprising a pair of positioning balls arranged in a spaced relationship.

9. The scanning probe electromagnetic chuck of claim 8 wherein, The actuating device further comprises a guide column, the guide column comprising a guide section and a positioning section, wherein the guide section is in the form of a truncated cone, and the positioning section is in the form of a cylinder.

10. The scanning probe electromagnetic chuck of claim 9 wherein, The mounting hole further comprises a limiting portion extending from the side wall of the mounting hole to the middle portion of the mounting hole, and the bottom surface of the actuating device abutting against the limiting portion.

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