A zero point positioning device

Abstract

The present invention relates to the technical field of machine tool equipment, and discloses a zero-point positioning device, which includes a base and at least two positioners arranged in groups, each of which is arranged on the base at intervals; the positioner includes a positioning key, which is inserted into the insertion port from top to bottom, and the positioning key has a positioning portion, and the outer periphery of the positioning portion includes two first positioning surfaces arranged opposite to each other and two second positioning surfaces arranged opposite to each other, the first positioning surface and the first matching surface are in clearance fit, and the second positioning surface and the second matching surface are in abutment with each other; wherein, in a group of the positioners, when observed along any cross section, the second matching surfaces of the two matching portions intersect. The present invention facilitates the assembly of the workpiece to be processed and the positioning key, while completely restricting the horizontal and vertical degrees of freedom of the workpiece to be processed, thereby making the workpiece to be processed fixedly connected to the positioning key accurately positioned.

Description

Technical Field

[0001] The invention relates to the technical field of machine tool equipment, in particular to a zero point positioning device. Background Art

[0002] The zero-point positioning device is a positioning and locking device that can ensure that the workpiece remains unchanged when it is moved from one station to another, from one process to another, or from one machine tool to another. This can save the auxiliary time for re-alignment and improve work efficiency.

[0003] The current zero-point positioning device generally uses a circular pin to directly connect with the workpiece. In order to facilitate the connection between the zero-point positioning device and the workpiece, a small gap is often left between the pin and the assembly hole of the workpiece. The gap will cause deviations in positioning accuracy, thereby causing displacement. Summary of the invention

[0004] The purpose of the present invention is to provide a zero point positioning device to solve the problem that a small gap between a pin and an assembly hole of a workpiece being processed may cause a deviation in positioning accuracy, thereby causing displacement.

[0005] To achieve the above object, the technical solution of the present invention is as follows:

[0006] A zero point positioning device comprises a base and at least two positioners arranged in a group, wherein each of the positioners is arranged on the base at intervals;

[0007] The locator comprises:

[0008] A shell seat, the shell seat is mounted on the base, the top surface of the shell seat is provided with an insertion port, the top of the insertion port has a matching section, the matching section includes two first matching surfaces that are oppositely arranged and two second matching surfaces that are oppositely arranged, the two first matching surfaces are spaced and arranged in parallel, the two second matching surfaces are spaced, the two second matching surfaces are inclined from top to bottom toward a side close to each other, and when observed along any cross section, the two second matching surfaces are arranged in parallel;

[0009] A positioning key is inserted into the insertion port from top to bottom, the positioning key has a positioning portion, the outer periphery of the positioning portion includes two first positioning surfaces that are oppositely arranged and two second positioning surfaces that are oppositely arranged, the first positioning surface is clearance-matched with the first matching surface, the second positioning surface is matched with the second matching surface and abuts, and the outer periphery of the positioning key is also provided with a locking groove, and the locking groove is located below the positioning portion;

[0010] A locking assembly, the locking assembly is arranged inside the shell seat, the locking assembly includes a driving mechanism and a locking block, the driving mechanism can drive the locking block to move between a locking position and an unlocking position, when the locking block is located at the locking position, the locking block is inserted into the locking groove so that the positioning key is locked on the shell seat, when the locking block is located at the unlocking position, the locking block is disengaged from the locking groove so that the positioning key can slide relative to the shell seat;

[0011] Among them, in a group of the positioners, when observed along any cross section, the second mating surfaces of the two mating parts intersect.

[0012] Furthermore, in a group of the positioners, when observed along any cross section, the second mating surfaces of the two mating parts are perpendicular to each other.

[0013] Furthermore, the housing seat comprises:

[0014] Bottom shell;

[0015] A cover body, the cover body is covered on the upper end of the bottom shell, and the bottom shell and the cover body cooperate to form a slot; and

[0016] Two fixing blocks are installed on the cover body, and the two fixing blocks are embedded on opposite sides of the top of the slot, and a gap is defined between the two fixing blocks, and the gap is connected with the slot to define the insertion port, and the second mating surface is defined on the sides of the two fixing blocks facing each other, and the interior of the fixing block is a hollow structure.

[0017] Furthermore, the positioning key also includes:

[0018] A positioning protrusion, the positioning protrusion is arranged on the top of the positioning portion and protrudes from the top surface of the housing seat; and

[0019] A bolt is installed on the positioning protrusion.

[0020] Furthermore, a guiding slope is provided at the lower end of the positioning key and is inclined from top to bottom toward the center of the positioning key.

[0021] Furthermore, a mounting cavity and a sliding track are provided in the housing seat, the mounting cavity is arranged around the outer circumference of the insertion port, and the sliding track connects the mounting cavity and the insertion port;

[0022] The driving mechanism comprises an annular elastic cavity, a spring and an abutment plate, all of which are arranged in the installation cavity; the annular elastic cavity is arranged around the insertion port; the abutment plate is connected to the lower end surface of the annular elastic cavity; the upper end of the spring abuts the abutment plate; the lower end of the spring abuts the shell seat; the locking block is slidably arranged in the sliding track; a slide groove is arranged on the abutment plate; the slide groove gradually extends obliquely from top to bottom toward the insertion port; the locking block has a guide column arranged in the slide groove and capable of sliding along the slide groove;

[0023] The inflation and deflation of the annular elastic cavity can drive the abutment plate to move up and down, thereby driving the locking block to slide along the sliding track, so that the locking block moves between the locking position and the unlocking position.

[0024] Furthermore, the annular elastic cavity is defined by the upper side surface of an annular extrusion plate arranged inside the shell seat and the shell seat; when the locking block is in the locking position, the annular extrusion plate protrudes upward, and when the locking block is in the unlocking position, the annular extrusion plate protrudes downward, and the abutment plate is fixedly connected to the lower end surface of the annular extrusion plate.

[0025] Furthermore, a limit rod inserted into the spring is provided in the shell seat, a limit channel for inserting the limit rod is provided at the lower end of the abutment plate, a limit stop ring protruding toward the inside of the limit channel is provided at the lower end of the limit channel, and a limit protrusion is provided at the upper end of the limit rod for limiting the upward movement of the limit stop ring.

[0026] Furthermore, the annular extrusion plate is detachably connected to the shell seat.

[0027] Further, two groups of the positioners are arranged on the base at intervals, each group of the positioners includes a first positioner and a second positioner, and when observed along any cross section, the second mating surfaces of the first positioners are parallel to each other, and when observed along any cross section, the second mating surfaces of the second positioners are parallel to each other.

[0028] The zero-point positioning device of the present invention has the beneficial effect compared with the prior art in that the second mating surface of the positioning part locks the positioning key, and in a group of the positioners, the second mating surfaces of the two mating parts intersect along any cross section, thereby limiting the freedom of the positioning key in the horizontal direction, and the positioning key is locked by the locking component in the positioner, limiting the freedom of the positioning key in the vertical direction, thereby making the processing workpiece fixedly connected to the positioning key accurately positioned; at the same time, the first positioning surface and the first mating surface are clearance-matched, thereby avoiding positioning interference caused by over-positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a cross-sectional view of a locked state of a positioner in a zero-point positioning device in Embodiment 1 of the present invention;

[0030] Figure 2 is a cross-sectional view of the unlocked state of the positioner in the zero-point positioning device of Example 1 of the present invention;

[0031] Figure 3 is a cross-sectional view of a locked state of a positioner (without a positioning key inserted) in a zero-point positioning device according to Embodiment 1 of the present invention;

[0032] Figure 4 yes Figure 3 The enlarged view of point A in the middle;

[0033] Figure 5 is a cross-sectional view of a zero-point positioning device connected to a workpiece to be processed in Example 1 of the present invention;

[0034] Figure 6 is a top view of a group of positioners of the zero point positioning device of Example 1 of the present invention;

[0035] Figure 7 is a top view of two groups of positioners of the zero point positioning device of Example 2 of the present invention;

[0036] Figure 8 is an external structural diagram of a zero point positioning device according to Embodiment 3 of the present invention;

[0037] Fig. 9 is a cross-sectional view of an end cover in a zero-point positioning device according to Embodiment 3 of the present invention;

[0038] In the figure, 1, positioner; 11, shell seat; 111, insertion port; 1111, first mating surface; 1112, second mating surface; 1113, fixing block; 1114, slot; 112, sliding track; 113, limiting rod; 1131, limiting protrusion; 114, bottom shell; 115, cover body; 1151, threaded hole; 1152, headless screw; 1153, clamping block; 116, installation cavity; 117, end cover; 1171, clamping part; 12, positioning key; 121, positioning part; 1 211. First positioning surface; 1212. Second positioning surface; 122. Locking groove; 123. Bolt; 124. Positioning protrusion; 125. Guide slope; 13. Locking assembly; 131. Drive mechanism; 1311. Annular elastic cavity; 13111. Annular extrusion plate; 1312. Spring; 1313. Limiting channel; 13131. Limiting ring; 1314. Abutment plate; 13141. Slide groove; 132. Locking block; 1321. Guide column; 2. Base; 3. Workpiece to be processed. DETAILED DESCRIPTION

[0039] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0040] Embodiment 1:

[0041] like Figure 1-3 As shown in Figures 5-6, a zero-point positioning device of a preferred embodiment of the embodiment of the present invention comprises a base 2 and at least two positioners 1 arranged in groups, each of which is arranged on the base 2 at intervals; by arranging multiple groups of positioners 1, the stress on the positioner 1 can be dispersed to reduce the force deformation of the positioner 1 and ensure the processing accuracy; the positioner 1 comprises a shell seat 11, a positioning key 12 and a locking assembly 13, the shell seat 11 is installed on the base 2, the top surface of the shell seat 11 is provided with an insertion port 111, the top of the insertion port 111 has a mating section, the mating section comprises two first mating surfaces 1111 arranged opposite to each other and two second mating surfaces 1112 arranged opposite to each other, the two first mating surfaces 1111 are arranged at intervals and in parallel, the two second mating surfaces 1112 are arranged at intervals, the two second mating surfaces 1112 are arranged inclined from top to bottom toward the side close to each other, and when observed along any cross section, the two second mating surfaces 1112 are arranged in parallel.

[0042] The positioning key 12 is inserted into the insertion port 111 from top to bottom, and the positioning key 12 has a positioning portion 121. The outer periphery of the positioning portion 121 includes two first positioning surfaces 1211 and two second positioning surfaces 1212 that are oppositely arranged. The first positioning surface 1211 is clearance-matched with the first matching surface 1111 (not shown in the figure), and the second positioning surface 1212 is matched and abutted with the second matching surface 1112. The outer periphery of the positioning key 12 is also provided with a locking groove 122, and the locking groove 122 is located below the positioning portion 121; the locking groove 122 is located below the positioning portion 121. The fixed component 13 is arranged inside the shell base 11, and the locking component 13 includes a driving mechanism 131 and a locking block 132. The driving mechanism 131 can drive the locking block 132 to move between a locked position and an unlocked position. When the locking block 132 is located at the locked position, the locking block 132 is inserted into the locking groove 122 so that the positioning key 12 is locked on the shell base 11. When the locking block 132 is located at the unlocked position, the locking block 132 is disengaged from the locking groove 122 so that the positioning key 12 can slide relative to the shell base 11.

[0043] Among them, in a group of the positioners 1, when observed along any cross section, the second mating surfaces 1112 of the two mating parts intersect.

[0044] Based on this, the second mating surface 1112 of the positioning part 121 locks the positioning key 12, and in a group of the positioners 1, when observed along any cross section, the second mating surfaces 1112 of the two mating parts intersect, thereby limiting the horizontal freedom of the positioning key 12. The positioning key 12 is locked by the locking assembly 13 in the positioner 1, limiting the vertical freedom of the positioning key 12, thereby making the workpiece 3 fixedly connected to the positioning key 12 accurately positioned; at the same time, the first positioning surface 1211 is clearance-fitted with the first mating surface 1111, thereby avoiding positioning interference caused by over-positioning.

[0045] Preferably, if Figure 5-6 As shown, in order to reduce over-positioning and installation interference, in a group of the positioners 1, when observed along any cross section, the second mating surfaces 1112 of the two mating parts are perpendicular to each other.

[0046] Furthermore, in order to make the second mating surface 1112 and the second positioning surface 1212 of the positioning portion 121 have an interference fit, the second mating surface 1112 is made of an elastic material.

[0047] Furthermore, if Figure 1-3 As shown, in order to facilitate the installation and disassembly of the locking assembly 13 inside the shell base 11, the shell base 11 includes a bottom shell 114, a cover body 115 and two fixing blocks 1113; the cover body 115 is covered on the upper end of the bottom shell 114, the cover body 115 and the bottom shell 114 are detachably connected, and the bottom shell 114 and the cover body 115 cooperate to form a slot 1114; the fixing blocks 1113 are installed on the cover body 115, and the two fixing blocks 1113 are embedded in the top of the slot 1114 On opposite sides, a gap is defined between the two fixing blocks 1113, and the gap is connected with the slot 1114 to define the insertion port 111. The second mating surface 1112 is defined on the sides facing each other of the two fixing blocks 1113. The interior of the fixing block 1113 is a hollow structure, and the hollow structure can increase the deformation degree of the fixing block 1113, thereby increasing the pressure applied by the second mating surface 1112 to the second positioning surface 1212, so that the positioning of the positioning key 12 is more precise and stable.

[0048] Furthermore, if Figure 2-3As shown, the positioning key 12 also includes a positioning protrusion 124 and a bolt 123. The positioning protrusion 124 is arranged at the top of the positioning portion 121. The positioning protrusion 124 may be rectangular in shape. The positioning protrusion 124 is provided with a through hole (not shown in the figure). The through hole connects the upper and lower ends of the positioning protrusion 124 and protrudes from the top surface of the shell seat 11. The bolt 123 is installed on the positioning protrusion 124. Specifically, the bolt 123 is inserted into the through hole from bottom to top and is fixedly connected with the positioning protrusion 124. The top of the bolt 123 is fixedly connected with the workpiece 3 to be processed. Further, in order to facilitate the insertion of the positioning key 12 into the insertion port 111, the lower end of the positioning key 12 is provided with a guiding inclined surface 125 inclined from top to bottom toward the center of the positioning key 12.

[0049] Furthermore, if Figure 3As shown, the shell seat 11 is further provided with an installation cavity 116 and a sliding track 112, the installation cavity 116 is arranged around the outer periphery of the insertion port 111, and the sliding track 112 communicates with the installation cavity 116 and the insertion port 111; the driving mechanism 131 comprises an annular elastic cavity 1311, a spring 1312 and an abutment plate 1314, all of which are arranged in the installation cavity 116, the annular elastic cavity 1311 is arranged around the insertion port 111, the abutment plate 1314 is connected to the lower end surface of the annular elastic cavity 1311, the upper end of the spring 1312 abuts the abutment plate 1314, and the lower end of the spring 1312 abuts the shell seat 11, the locking block 132 is slidably arranged in the sliding track 112, and the abutment plate 1314 is provided with a slide groove 13141, and the slide groove 13141 gradually moves from top to bottom toward the insertion port. The opening 111 extends obliquely, and the locking block 132 has a guide column 1321 arranged in the slide groove 13141 and capable of sliding along the slide groove 13141; the spring 1312 is always in a compressed state, and the inflation and deflation of the annular elastic cavity 1311 can drive the abutment plate 1314 to slide up and down, thereby driving the locking block 132 to slide along the sliding track 112, so that the locking block 132 moves between the locked position and the unlocked position; when the annular elastic cavity 1311 is in a deflated state, the abutment plate 1314 is in a high position. At this time, the locking block 132 locks the positioning key 12. The purpose of this design is to ensure that the positioner 1 fixes the positioning key 12 without the need for any energy, so as to prevent the positioner 1 from being unable to normally lock the positioning key 12 in an emergency such as a power outage, resulting in a safety accident caused by the positioning key 12 popping out. When the annular elastic cavity 1311 is in an inflated state, the abutment plate 1314 is in a low position and drives the locking block 132 to unlock the positioning key 12. In addition, when the positioning key 12 is not inserted into the insertion port 111, the locking block 132 is generally in a locked state. Figure 3 As shown, the locking block 132 is in the unlocked state only when the positioning key 12 needs to be inserted in front of the insertion port 111 and the positioning key 12 needs to be pulled out.

[0050] Specifically, Figure 1-3As shown, in order to make the lower surface of the annular elastic cavity 1311 a hard surface and improve its response speed of inflation and downward pressure, the annular elastic cavity 1311 is formed by the upper side of the annular extrusion plate 13111 arranged inside the shell seat 11 and the shell seat 11; the annular extrusion plate 13111 is made of a deformable material, and when inflated, the annular extrusion plate 13111 protrudes downward, and the annular extrusion plate 13111 pushes the abutment plate 1314 to move downward, and when deflated, the annular extrusion plate 13111 protrudes upward, and the spring 1312 rebounds and pushes the The abutment plate 1314 moves upward. As an expansion solution, the annular extrusion plate 13111 can be slid up and down and sealedly connected to the shell seat 11, or an airbag is arranged between the annular extrusion plate 13111 and the shell seat 11, and the annular extrusion plate 13111 is controlled to move up and down by inflation and deflation of the airbag. Thus, the annular extrusion plate 13111 can move up and down as a whole. Furthermore, in order to facilitate the replacement of the annular extrusion plate 13111 and the disassembly or installation of the driving mechanism 131, the annular extrusion plate 13111 is detachably connected to the shell seat 11.

[0051] Furthermore, if Figure 1-3 As shown, in order to limit the spring 1312 to perform telescopic movement within a limited space, a limiting rod 113 inserted into the spring 1312 is provided in the shell seat 11, thereby limiting the spring 1312 from telescoping in the extending direction of the limiting rod 113. In order to keep the spring 1312 always in a compressed state, a limiting protrusion 1131 is provided at the upper end of the limiting rod 113, and a limiting channel 1313 for inserting the limiting rod 113 is provided at the lower end of the abutment plate 1314. A limiting baffle ring 13131 protruding toward the inside of the limiting channel 1313 is provided at the lower end of the limiting rod 113. A limiting protrusion 1131 is provided for limiting the upward movement of the limiting stop ring 13131. When the annular elastic cavity 1311 is exhausted outwardly, the spring 1312 presses the annular extrusion plate 13111 upward, so that the annular extrusion plate 13111 drives the abutment plate 1314 to move upward until the limiting protrusion 1131 abuts against the limiting stop ring 13131, and the annular extrusion plate 13111 reaches the highest position. The above-mentioned arrangement effectively ensures that the spring 1312 is in a compressed state when the locking block 132 is in the unlocking position, thereby ensuring that the locking assembly 13 works stably.

[0052] Embodiment 2:

[0053] Different from the embodiment 1, some embodiments 2 of the present invention include two groups of positioners 1, such as Figure 7As shown, two groups of the positioners 1 are spaced apart on the base 2, and each group of the positioners 1 includes a first positioner 1 and a second positioner 1. When observed along any cross section, the second mating surfaces 1112 of each of the first positioners 1 are parallel to each other. When observed along any cross section, the second mating surfaces 1112 of each of the second positioners 1 are parallel to each other.

[0054] Embodiment 3:

[0055] The difference between Example 3 and Example 1 is:

[0056] like Figure 8 As shown, a cavity (not shown in the figure) is provided inside the positioning key 12. The purpose of providing the cavity is to make the positioning key 12 have an interference fit when being locked by the locking block 132, thereby improving the position accuracy of the positioning key 12. Furthermore, without affecting the fixing effect of the bolt 123, cavities (not shown in the figure) are provided at intervals on the side walls of the through hole; without affecting the locking effect of the locking groove 122 and the locking block 132, cavities are provided at intervals on the outer edge of the locking groove 122. The positioner 1 is provided with a threaded hole 1151 that passes through the top of the positioner 1 and the side wall of the positioner 1. A headless screw 1152 is provided inside the threaded hole 1151. The positioner 1 abuts against the base 2 through the headless screw 1152 to fix the positional relationship between the positioner 1 and the base 2, thereby improving the positioning accuracy of the positioner 1.

[0057] like Fig. 9 As shown, the fixing block 1113 is installed on the cover body 115 through the end cover 117. The fixing block 1113 is fixedly connected to the end cover 117. The end cover 117 is provided with a clamping portion 1171 extending downward. The cover body 115 is provided with a clamping block 1153 cooperating with the clamping portion 1171. The clamping portion 1171 can be elastically deformed. Thus, the end cover 117 and the cover body 115 are detachably connected. The purpose of such design is to facilitate the replacement of the worn fixing block 1113 and ensure the accurate positioning of the positioning key 12.

[0058] The working process of the present invention is as follows: first, a group of the positioning keys 12 are connected to the workpiece 3 to be processed by the bolts 123, and then compressed air is introduced into the annular elastic cavity 1311, and the annular extrusion plate 13111 bulges and deforms downward, pushing the abutment plate 1314 to overcome the elastic force of the spring 1312 and move downward, and the slide groove 13141 moves downward at the same time, and the guide column 1321 in the slide groove 13141 is pushed by the slide groove 13141, driving the locking block 132 away from the insertion port 111, so that the locking block 132 is in an unlocked state, and the positioning key 12 is inserted into the insertion port 111; when locking is required, the annular elastic cavity 1311 is deflated, the extrusion force on the spring 1312 is reduced, and the spring 1312 pushes the abutment plate 1314 to move upward, and the locking block 132 gradually approaches the locking groove 122, and finally the locking of the positioning key 12 is completed.

[0059] In summary, the second mating surface 1112 of the positioning part 121 locks the positioning key 12, and in a group of the positioners 1, when observed along any cross section, the second mating surfaces 1112 of the two mating parts intersect, thereby limiting the horizontal freedom of the positioning key 12. The positioning key 12 is locked by the locking assembly 13 in the positioner 1, limiting the vertical freedom of the positioning key 12, thereby enabling the workpiece 3 fixedly connected to the positioning key 12 to be accurately positioned; at the same time, the first positioning surface 1211 is clearance-fitted with the first mating surface 1111, thereby avoiding positioning interference caused by over-positioning.

[0060] It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the "first" information may also be referred to as the "second" information, and similarly, the "second" information may also be referred to as the "first" information. In addition, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0061] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A zero point positioning device, characterized in that: It comprises a base and at least two positioners arranged in a group, each of the positioners is arranged on the base at intervals; The locator comprises:

4. The repairing kit for automotive dents, according to claim 1, wherein the two foot pieces are made of the same material, and the two foot pieces are made of the same material. The two foot pieces are made of the same material and are suitable for being used in the repair of foot-tips and for helping in the repair of foot-tips. A positioning key is inserted into the insertion port from top to bottom, the positioning key has a positioning portion, the outer periphery of the positioning portion includes two first positioning surfaces that are oppositely arranged and two second positioning surfaces that are oppositely arranged, the first positioning surface is clearance-matched with the first matching surface, the second positioning surface is matched with the second matching surface and abuts, and the outer periphery of the positioning key is also provided with a locking groove, and the locking groove is located below the positioning portion; A locking assembly, the locking assembly is arranged inside the shell seat, the locking assembly includes a driving mechanism and a locking block, the driving mechanism can drive the locking block to move between a locking position and an unlocking position, when the locking block is located at the locking position, the locking block is inserted into the locking groove so that the positioning key is locked on the shell seat, when the locking block is located at the unlocking position, the locking block is disengaged from the locking groove so that the positioning key can slide relative to the shell seat; Among them, in a group of the positioners, when observed along any cross section, the second mating surfaces of the two mating parts intersect.

2. The zero point positioning device according to claim 1, characterized in that: In a group of the positioners, when viewed along any cross section, the second mating surfaces of the two mating parts are perpendicular to each other.

3. The zero point positioning device according to claim 1, characterized in that: The positioning key also includes: A positioning protrusion, the positioning protrusion is arranged on the top of the positioning portion and protrudes from the top surface of the housing seat; and A bolt is installed on the positioning protrusion.

4. The zero point positioning device according to any one of claims 1 to 3, characterized in that: The lower end of the positioning key is provided with a guiding inclined surface which is inclined from top to bottom toward the center of the positioning key.

5. The zero point positioning device according to claim 1, characterized in that: The housing seat is further provided with an installation cavity and a sliding track, wherein the installation cavity is arranged around the outer periphery of the insertion port, and the sliding track is connected with the installation cavity and the insertion port; The driving mechanism comprises an annular elastic cavity, a spring and an abutment plate, all of which are arranged in the installation cavity; the annular elastic cavity is arranged around the insertion port; the abutment plate is connected to the lower end surface of the annular elastic cavity; the upper end of the spring abuts the abutment plate; the lower end of the spring abuts the shell seat; the locking block is slidably arranged in the sliding track; a slide groove is arranged on the abutment plate; the slide groove gradually extends obliquely from top to bottom toward the insertion port; the locking block has a guide column arranged in the slide groove and capable of sliding along the slide groove; The inflation and deflation of the annular elastic cavity can drive the abutment plate to move up and down, thereby driving the locking block to slide along the sliding track, so that the locking block moves between the locking position and the unlocking position.

6. The zero point positioning device according to claim 5, characterized in that: The annular elastic cavity is defined by the upper side surface of the annular extrusion plate arranged inside the shell seat and the shell seat; when the locking block is in the locking position, the annular extrusion plate protrudes upward, and when the locking block is in the unlocking position, the annular extrusion plate protrudes downward, and the abutment plate is fixedly connected to the lower end surface of the annular extrusion plate.

7. The zero point positioning device according to claim 6, characterized in that: A limit rod inserted into the spring is provided in the shell seat, a limit channel for inserting the limit rod is provided at the lower end of the abutment plate, a limit ring protruding into the inner part of the limit channel is provided at the lower end of the limit channel, and a limit protrusion for limiting the upward movement of the limit ring is provided at the upper end of the limit rod.

8. The zero point positioning device according to claim 6, characterized in that: The annular extrusion plate is detachably connected to the shell seat.

9. The zero point positioning device according to claim 1, characterized in that: Two groups of the positioners are arranged on the base at intervals, each group of the positioners includes a first positioner and a second positioner, and when observed along any cross section, the second mating surfaces of the first positioners are parallel to each other, and when observed along any cross section, the second mating surfaces of the second positioners are parallel to each other.

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