Measuring head with active zero returning device

Abstract

The embodiment of the utility model provides a measuring head with an active zeroing device, which comprises a main body, a measuring needle seat, an active zeroing device and an active zeroing device, the upper substrate is parallel to the probe seat, and a first distance is formed between the upper substrate and the probe seat; the Z-axis spring parallelogram assembly is used for enabling the probe seat and the upper substrate to keep parallel displacement; the active zero returning device is arranged between the probe seat and the upper substrate and comprises a balance spring group, and the balance spring group comprises a middle ring, a first spring which is arranged on the upper side of the middle ring and is connected with the middle ring and the upper substrate, and a second spring which is arranged on the lower side of the middle ring and is connected with the middle ring and the probe seat; the active zeroing device further comprises a driving device connected with the middle ring, the driving device is configured to drive the middle ring to move and enable the upper substrate to keep a first distance from the probe seat, and the active zeroing device can enable the upper substrate to keep a second distance from the probe seat when probe assemblies of different models, especially different weights, are replaced. And the probe seat is always kept at the zero position.

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 that can realize the measuring capacity of geometric shape, length and circular division in a hexahedron space range, and its measuring functions include size precision, positioning precision, geometric precision and profile precision, and is widely applied to the mould, aviation, automobile, electronic and other industries.

[0003] Generally, the three-coordinate measuring machine needs to be configured with a measuring head to give an accurate trigger signal through the measuring head, in order to realize higher precision, in order to adapt to different types of measuring needles, a balancing device and an actuating device are usually required to be set to keep the measuring needle seat at zero, such as the structure shown in the document US3869799A, a spring structure is arranged between the upper plate and the lower plate to form a passive balancing device, but with the diversification of the type of measuring needle, the passive balancing device cannot meet the actual needs.

[0004] Therefore, a new technical solution is needed to solve the above technical problems. UTILITY MODEL CONTENT

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

[0006] A measuring head with an active zero reset device, comprising a main body, comprising:

[0007] A measuring needle seat;

[0008] An upper base plate is arranged in parallel with the measuring needle seat, and a first distance is included between the upper base plate and the measuring needle seat;

[0009] A Z-axis spring parallelogram assembly is used to keep the measuring needle seat and the upper base plate parallel displacement;

[0010] An active zero reset device is arranged between the measuring needle seat and the upper base plate, and comprises a balance spring group, the balance spring group comprises a middle ring, a first spring arranged on the upper side of the middle ring and connected with the middle ring and the upper base plate, and a second spring arranged on the lower side of the middle ring and connected with the middle ring and the measuring needle seat, the active zero reset device further comprises a driving device connected with the middle ring, and the driving device is configured to drive the middle ring to move and keep the upper base plate and the measuring needle seat at the first distance.

[0011] The driving device comprises a worm gear assembly and a worm for driving the worm gear assembly to rotate, wherein the worm gear assembly comprises a worm disc matched with the worm and an adjusting shaft coaxially arranged with the worm disc, the middle ring comprises an adjusting hole, the adjusting shaft is arranged in the adjusting hole, and the adjusting shaft is configured to move in the vertical direction.

[0012] The worm is arranged in the vertical direction, and the rotation axis of the worm disc is in the horizontal direction.

[0013] The probe further comprises a main bracket, the main bracket comprises a guide block configured to move in the vertical direction, and the worm gear assembly is arranged on the guide block.

[0014] The first spring is the same as the second spring.

[0015] The Z-axis spring parallelogram assembly comprises a left structure plate, a Z-axis upper plate, a right structure plate and a Z-axis lower plate, wherein a leaf spring is arranged between the left structure plate and the Z-axis upper plate, the Z-axis upper plate and the right structure plate, the right structure plate and the Z-axis lower plate, and the Z-axis lower plate and the left structure plate, and the leaf spring is configured to elastically deform in the Z-axis direction.

[0016] The left structure plate and the right structure plate are arranged in the vertical direction, the upper substrate is fixed on the left structure plate, and the probe needle seat is connected to the right structure plate.

[0017] The right structure plate comprises a horizontal plate parallel to the upper substrate, and the probe needle seat is connected to the horizontal plate.

[0018] An actuator is further arranged between the upper substrate and the horizontal plate, for moving the horizontal plate and the probe needle seat in the Z-axis direction.

[0019] The actuator is a voice coil motor comprising a magnet and a coil set, the upper substrate comprises a notch portion, the coil set comprises a coil seat fixed in the notch portion, the magnet is fixed on the horizontal plate, the upper substrate further comprises a pair of fork-shaped portions, and the upper substrate is fixed on the left structure plate through the fork-shaped portions.

[0020] Beneficial effects: the utility model discloses a measuring head, the measuring head with the initiative zero return device, including main part, including: measuring needle seat;Upper base plate, with the parallel arrangement of measuring needle seat, the upper base plate with measuring needle seat between including first distance;Z axis spring parallelogram assembly, for making measuring needle seat and upper base plate keep parallel displacement;Initiative zero return device, set up between measuring needle seat and upper base plate, including balance spring group, the balance spring group includes middle ring, set up on the upper side of middle ring and connect middle ring with the first spring of upper base plate and set up in the lower side of middle ring and connect middle ring with the second spring of measuring needle seat, the initiative zero return device still includes the drive arrangement connected with middle ring, the drive arrangement is configured as drive the movement of middle ring and make upper base plate and measuring needle seat keep first distance, through initiative zero return device can make when replacing different models especially different weight measuring needle assembly, measuring needle seat always keep in zero point position. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The measuring head schematic diagram of the utility model embodiment;

[0022] Figure 2 For Figure 1 The simplified structure schematic diagram of;

[0023] Figure 3 For Figure 1 The three-dimensional schematic diagram of initiative zero return device in;

[0024] Figure 4 For Figure 3 The left view of;

[0025] Figure element explanation:

[0026] Main part 10;Z axis spring parallelogram assembly 110;Left structure plate 111;Right structure plate 112;Cross plate 1121;Z axis lower plate 113;Leaf spring 1131;Z axis upper plate 114;Upper base plate 115;Forked portion 1151;Notch portion 1152;Initiative zero return device 120;Worm gear assembly 121;Worm wheel disc 1211;Adjusting shaft 1212;Balance spring group 122;Middle ring 1221;First spring 1222;Second spring 1223;Worm 124;Driving motor 125;Main support 126;Actuator 130;Coil group 131;Magnet 132;Displacement sensor 140;Measuring needle assembly 20;Measuring needle seat 21. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and effect of the present application more clear and definite, the following will combine the drawings to carry out the detailed description of the embodiment of the technical scheme of the present application. The following embodiment is only used for more clearly explaining the technical scheme of the present application, therefore only as example, and cannot limit the protection scope of the present application.

[0028] Please refer to the attached drawings Figures 1-4 The utility model embodiment provides a kind of probe, the probe includes probe base 21, upper substrate 115, Z axis spring parallelogram component 110 and active zero reset device 120.

[0029] The probe base 21 is configured to connect the probe assembly 20, and it can be understood that the probe assembly 20 can be various structures and forms of existing probe forms, in Figure 1 A probe set with five probes is shown to facilitate measurement of products from different directions / positions, and the probe base 21 includes a quick connection assembly to enable the probe assembly 20 to be quickly connected to the probe base 21. In a specific embodiment, the quick connection assembly includes a magnetic attraction device.

[0030] The upper substrate 115 is arranged in parallel with the probe base 21.

[0031] A Z axis spring parallelogram component 110 is included between the probe base 21 and the upper substrate 115 to maintain the parallelism of the probe base 21 and the upper substrate 115. Specifically, the Z axis spring parallelogram component 110 includes a left structure plate 111, a Z axis upper plate 114, a right structure plate 112, and a Z axis lower plate 113. Leaf springs 1131 are arranged between the left structure plate 111 and the Z axis upper plate 114, the Z axis upper plate 114 and the right structure plate 112, the right structure plate 112 and the Z axis lower plate 113, and the Z axis lower plate 113 and the left structure plate 111. These leaf springs 1131 are configured to be elastically deformed in the Z axis direction.

[0032] Specifically, the left structure plate 111 and the right structure plate 112 are arranged vertically, and the Z axis upper plate 114 and the Z axis lower plate 113 are arranged horizontally between the left structure plate 111 and the right structure plate 112. The Z axis upper plate 114 has a leaf spring 1131 arranged on each of its left and right sides. The leaf spring 1131 arranged on the left side is arranged horizontally and connects the left structure plate 111 and the Z axis upper plate 114, and the leaf spring 1131 arranged on the right side is arranged horizontally and connects the Z axis upper plate 114 and the right structure plate 112. Similarly, the Z axis lower plate 113 is also arranged horizontally between the left structure plate 111 and the right structure plate 112, and a leaf spring 1131 is arranged on each of its left and right sides. The leaf spring 1131 arranged on the left side is arranged horizontally and connects the left structure plate 111 and the Z axis lower plate 113, and the leaf spring 1131 arranged on the right side is arranged horizontally and connects the Z axis lower plate 113 and the right structure plate 112. Through the left structure plate 111, the Z axis upper plate 114, the right structure plate 112, the Z axis lower plate 113, and the leaf springs 1131 arranged therebetween, a spring parallelogram structure is formed.

[0033] The upper substrate 115 is fixedly connected with the left structure plate 111, and the probe seat 21 is arranged on the right structure plate 112, that is, the left structure plate 111 and the right structure plate 112 are kept parallel moving in the vertical direction by the Z-axis spring parallelogram assembly 110, and then the upper substrate 115 fixedly connected with the left structure plate 111 and the probe seat 21 connected with the right structure plate 112 are kept parallel moving in the vertical direction.

[0034] In addition, the right structure plate 112 includes a horizontal plate 1121 parallel to the upper substrate 115, and the probe seat 21 is connected with the horizontal plate 1121. In a specific embodiment, the probe seat 21 and the horizontal plate 1121 further include an X-axis spring parallelogram assembly and a Y-axis spring parallelogram assembly, so that the probe seat 21 can move relative to the upper substrate 115 in the X-axis direction and the Y-axis direction, and corresponding sensors are arranged to detect the displacement of the probe seat 21 relative to the upper substrate 115 in the X-axis direction and the Y-axis direction. The structures of the X-axis spring parallelogram assembly and the Y-axis spring parallelogram assembly are similar to that of the Z-axis spring parallelogram assembly 110, and will not be described here.

[0035] It can be understood that the upper substrate 115 and the probe seat 21 include a first distance, and the main body 10 further includes a driving zero-return device 120 arranged between the probe seat 21 and the upper substrate 115, including a balance spring group 122, the balance spring group 122 including a middle ring 1221, a first spring 1222 arranged on the upper side of the middle ring 1221 and connected with the middle ring 1221 and the upper substrate 115, and a second spring 1223 arranged on the lower side of the middle ring 1221 and connected with the middle ring 1221 and the probe seat 21. The driving zero-return device 120 further includes a driving device connected with the middle ring 1221, and the driving device is configured to drive the movement of the middle ring 1221 and keep the upper substrate 115 and the probe seat 21 at the first distance.

[0036] In the embodiment, the driving device includes a worm gear assembly 121 and a worm 124 for driving the worm gear assembly 121 to rotate, wherein the worm gear assembly 121 includes a worm gear disc 1211 matched with the worm 124 and an adjusting shaft 1212 coaxially arranged with the worm gear disc 1211, the middle ring 1221 includes an adjusting hole, the adjusting shaft 1212 is arranged in the adjusting hole, and the adjusting shaft 1212 is configured to move in the vertical direction to enable the middle ring 1221 to move in the vertical direction, so that the upper substrate 115 and the probe seat 21 keep the first distance.

[0037] In the embodiment, the worm 124 is arranged in a vertical direction, more specifically, the axis of the worm 124 is in the vertical direction, and the rotation axis of the worm wheel disc 1211 is in a horizontal direction, so that when the worm 124 rotates, the worm wheel disc 1211 moves in the vertical direction while rotating, and drives the adjusting shaft 1212 and the middle ring 1221 to move in the vertical direction.

[0038] Further, the measuring head further comprises a main bracket 126, the main bracket 126 comprises a guide block, the guide block is configured to be movable in the vertical direction, and the worm wheel assembly 121 is arranged on the guide block, so that when the worm 124 rotates, the worm wheel assembly 121 and the guide block move in the vertical direction.

[0039] Further, the main bracket 126 is arranged on the left structure plate 111.

[0040] Further, the first spring 1222 is formed by winding a first wire body, and comprises a first spiral part and a first connecting part connecting the first spiral part and the middle ring 1221, the second spring 1223 is formed by winding a second wire body, and comprises a second spiral part and a second connecting part connecting the second spiral part and the middle ring 1221, the second wire body is an extension of the first wire body, that is, the first spring 1222 and the second spring 1223 are in an integral structure, and the middle ring 1221 is formed by winding the first wire body.

[0041] Further, the middle ring 1221 comprises a plurality of parallel arranged coil cords, each coil cord is formed by winding the first wire body.

[0042] Further, the first spring 1222 and the second spring 1223 are the same, that is, the elastic modulus of the first spring 1222 and the elastic modulus of the second spring 1223 are the same, in a specific embodiment, the diameter and the number of turns of the first spiral part are the same as the diameter and the number of turns of the second spiral part.

[0043] In addition, the driving device further comprises a driving motor 125 for driving the worm 124 to rotate, and the driving motor 125 is coaxially arranged with the worm 124.

[0044] It can be understood that the measuring head further comprises a displacement sensor 140 for acquiring the displacement amount of the probe seat 21 in the Z-axis direction, in the embodiment, the displacement sensor 140 is an inductance displacement sensor 140.

[0045] Meanwhile, an actuating device 130 is arranged between the upper substrate 115 and the horizontal plate 1121, for moving the horizontal plate 1121 and the probe holder 21 along the Z-axis direction, in the embodiment, the actuating device 130 is a voice coil motor, comprising a magnet 132 and a coil set 131.

[0046] Further, the upper substrate 115 comprises a notch part 1152, the coil set 131 comprises a coil holder, the coil holder is fixed in the notch part 1152, and the magnet 132 is fixed on the horizontal plate 1121.

[0047] Meanwhile, the upper substrate 115 further comprises a pair of fork-shaped parts 1151, and the upper substrate 115 is fixed on the left structure plate 111 through the fork-shaped parts 1151.

[0048] The probe will be further described below by the specific form of returning the probe to zero.

[0049] Since the probe is usually arranged at the end of the Z-axis of the coordinate measuring machine and arranged in the manner that the probe needle faces downward, when a standard probe needle assembly 20 is connected on the probe holder 21, the first spring 1222 and the second spring 1223 stretch the centering ring 1221 and make the centering ring 1221 at an equilibrium point, which is defined as zero point, when different probe needle assemblies 20 are used, due to the different gravity, the second spring 1223 at the lower side is contracted or stretched and makes the zero point position change, the displacement sensor 140 acquires the displacement amount, the driving device drives the centering ring 1221 to move and makes the zero point position return, that is, makes the first distance keep unchanged, so that the consistent zero point can be kept all the time under different probe needle assemblies 20, meanwhile, when the measurement is carried out, the probe needle assembly 20 makes the position of the probe holder 21 change and further makes the corresponding position sensor send signals, so as to acquire the detection information.

[0050] The above description is only the embodiment of the utility model, and does not limit the patent range of the utility model, and any equivalent structure or equivalent flow transformation by using the contents of the utility model specification and drawings, or direct or indirect application in other related technical fields, are all included in the patent protection range of the utility model.

Claims

1. A probe head having an active zero return device comprising a body, characterised in that, The utility model relates to a probe head, comprising: a probe base; an upper substrate arranged in parallel with the probe base, the upper substrate and the probe base comprising a first distance therebetween; a Z-axis spring parallelogram assembly for enabling parallel displacement of the probe base and the upper substrate; a zero-return device arranged between the probe base and the upper substrate, comprising a balance spring set, the balance spring set comprising a middle ring, a first spring arranged on the upper side of the middle ring and connected to the middle ring and the upper substrate, and a second spring arranged on the lower side of the middle ring and connected to the middle ring and the probe base, the zero-return device further comprising a driving device connected to the middle ring, the driving device being configured to drive the middle ring to move and keep the upper substrate and the probe base at the first distance.

2. The probe head of claim 1, wherein The driving device comprises a worm gear assembly and a worm for driving the worm gear assembly to rotate, wherein the worm gear assembly comprises a worm wheel disc matched with the worm and an adjusting shaft arranged coaxially with the worm wheel disc, the middle ring comprises an adjusting hole, the adjusting shaft is arranged in the adjusting hole, and the adjusting shaft is configured to move in the vertical direction.

3. The probe head of claim 2, wherein, The worm is arranged in the vertical direction, and the rotation axis of the worm wheel disc is in the horizontal direction.

4. The probe head of claim 2 wherein, The probe head further comprises a main support, the main support comprises a guide block, the guide block is configured to be movable in the vertical direction, and the worm gear assembly is arranged on the guide block.

5. The probe head of claim 4, wherein, The first spring and the second spring are identical.

6. The probe head of claim 5, wherein, The Z-axis spring parallelogram assembly comprises a left structural plate, a Z-axis upper plate, a right structural plate, and a Z-axis lower plate, wherein a leaf spring is arranged between the left structural plate and the Z-axis upper plate, the Z-axis upper plate and the right structural plate, the right structural plate and the Z-axis lower plate, and the Z-axis lower plate and the left structural plate, and the leaf spring is configured to be elastically deformed in the Z-axis direction.

7. The probe head of claim 6 wherein, The left structural plate and the right structural plate are arranged in the vertical direction, the upper substrate is fixed on the left structural plate, and the probe base is connected to the right structural plate.

8. The probe head of claim 7, wherein The right structural plate comprises a horizontal plate, the horizontal plate is parallel to the upper substrate, and the probe base is connected to the horizontal plate.

9. The probe head of claim 8, wherein, An actuating device is further arranged between the upper substrate and the horizontal plate, for enabling the horizontal plate and the probe base to move in the Z-axis direction.

10. The probe head of claim 9, wherein, The actuating device is a voice coil motor, comprising a magnet and a coil set, the upper substrate comprises a notch portion, the coil set comprises a coil seat, the coil seat is fixed in the notch portion, the magnet is fixed on the horizontal plate, the upper substrate further comprises a pair of fork-shaped portions, and the upper substrate is fixed on the left structural plate through the fork-shaped portions.

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