A detection pin assembly

Abstract

The invention discloses a detection pin assembly, comprising a gauge bracket, a marking pin and a center pin. The gauge bracket is provided with a mounting hole in the longitudinal direction, the marking pin is slidably inserted into the mounting hole and can rotate around the axial direction of the mounting hole, the marking pin is provided with a guide hole coaxial with the mounting hole, the center pin is slidably inserted into the guide hole and can rotate around the axial direction of the guide hole, the center pin has a detection end and a handle end extending from both ends of the guide hole, the detection end comprises a first detection section and a second detection section which are sequentially arranged in a direction away from the handle end, when the center pin slides in the guide hole until the first detection section extends out of the guide hole from the marking end, the first limiting structure limits the sliding of the marking pin in the mounting hole and the axial rotation around the mounting hole, the second limiting structure limits the first detection section from sliding into the guide hole in the longitudinal direction and limits the axial rotation of the center pin around the mounting hole, and the detection pin assembly of the technical solution of the invention has three functions of marking detection, passability detection and positioning.

Description

Technical Field

[0001] The invention relates to the technical field of inspection tools, and in particular to an inspection pin assembly. Background Art

[0002] At present, manual inspection fixtures generally use movable plug-in inspection pins to detect the position of holes on parts. In addition to using through-stop type inspection pins to detect whether the position of the holes is qualified, it is also required to use a marking pin to visually inspect the offset direction and approximate offset of the holes. In the prior art, inspection pins that can be used for both passing inspection and marking are generally used. However, when the part hole is used as a test hole and needs to be a positioning hole for investigation, the diameter of the marking pin is larger than that of the positioning pin, and the diameter of the passing inspection pin is smaller than that of the positioning pin, and the inspection pin cannot realize the positioning pin function. Summary of the invention

[0003] The main purpose of the present invention is to provide a detection pin assembly, aiming to solve the problem in the prior art that the detection pin cannot be used for marking, passing and positioning at the same time.

[0004] To achieve the above object, the detection pin assembly proposed by the present invention comprises:

[0005] The inspection fixture bracket is provided with mounting holes along the longitudinal direction;

[0006] A marking pin extends longitudinally, is slidably disposed in the mounting hole and can rotate around the axial direction of the mounting hole, the marking pin is provided with a guide hole coaxial with the mounting hole, the marking pin has a marking end, and a marking tip for marking is convexly disposed on the end edge of the marking end, so as to detect the position of the part hole; and

[0007] A center pin extends longitudinally, is slidably inserted into the guide hole and can rotate around the axial direction of the guide hole, the center pin has a detection end and a handle end extending from both ends of the guide hole, the detection end is arranged corresponding to the marking end, the detection end includes a first detection section and a second detection section sequentially arranged in a direction away from the handle end, the cross section of the first detection section is larger than the cross section of the second detection section to form a step, the first detection section is used to cooperate with the part hole for positioning, and the second detection section is used to detect the passability of the part hole;

[0008] In which, the detection pin assembly also includes a first limiting structure and a second limiting structure. When the center pin slides in the guide hole until the first detection section extends out of the guide hole from the marking end, the first limiting structure limits the marking pin from sliding in the mounting hole and axially rotating around the mounting hole, and the second limiting structure limits the first detection section from sliding into the guide hole in the longitudinal direction and limits the center pin from axially rotating around the mounting hole.

[0009] Optionally, the first limiting structure comprises a limiting member provided on the gauge bracket, and the limiting member can move in a direction approaching and away from the marking pin;

[0010] When the limiting member is close to the marking pin, the marking pin can be restricted from sliding in the mounting hole and rotating around the axial direction of the mounting hole.

[0011] Optionally, the gauge bracket is provided with an elongated hole that is longitudinally penetrated, and the length direction of the elongated hole is arranged to extend in the transverse direction;

[0012] The limiting member extends in the transverse direction, one end of which can be clamped with the marking pin, and the other end of which is provided with a connecting hole extending in the longitudinal direction;

[0013] The first limiting structure also includes an adjusting bolt extending in the longitudinal direction, passing through the elongated hole, and locked in the connecting hole.

[0014] Optionally, the first limiting structure further includes a groove, which is arranged along the circumference of the scribing pin;

[0015] A plurality of locking teeth which can be locked with the groove are formed on one end of the limiting member close to the marking pin.

[0016] Optionally, the second limiting structure includes:

[0017] A card platform is convexly arranged outside the first detection section; and

[0018] A clamping groove, provided on the inner side wall of the guide hole and penetrating the end surface of the scribed end, so as to clamp the clamping platform, restrict the first detection section from sliding into the guide hole in the longitudinal direction and restrict the center pin from rotating axially around the mounting hole;

[0019] The inner side wall of the guide hole is further provided with a guide groove extending in the longitudinal direction, and the guide groove is arranged through the end surface of the marking end to be slidably connected with the card table, so that the first detection section can slide into the guide hole in the longitudinal direction;

[0020] The guide groove and the clamping groove are arranged at intervals along the circumference of the guide hole.

[0021] Optionally, the second limiting structure further includes a spring member extending in the longitudinal direction, wherein the spring member is sleeved with the center pin, one end of the spring member is connected to the handle end, and the other end of the spring member is in contact with the marking pin;

[0022] When the card platform is engaged with the card slot, the spring element is in a compressed state.

[0023] Optionally, the detection pin assembly further comprises a pin sleeve disposed in the mounting hole, and the pin sleeve is slidably sleeved on the marking pin.

[0024] Optionally, the pin sleeve is arranged in the mounting hole by interference fit.

[0025] Optionally, the handle end of the center pin is provided with a convex portion protruding toward its circumferential side.

[0026] Optionally, the projection comprises a handle ball.

[0027] In the technical solution of the present invention, the center pin can slide longitudinally and rotate around the axial direction of the guide hole relative to the marking pin. When it is necessary to detect the passability of the part hole, the center pin is operated by the handle end to slide longitudinally until the second detection section passes through the part hole; when it is necessary to detect the position of the part hole, the center pin or the marking pin is operated to rotate the marking pin so that the marking tip draws a circle on the part surface corresponding to the part hole, and the offset direction and offset amount of the circle and the part hole are observed; when the part hole needs to be used as a positioning hole, the center pin slides in the guide hole until the first detection section extends out of the guide hole from the marking end, and the first detection section The cross section is larger than the second detection section to fit the part hole for positioning. At this time, because the positioning pin requires a high position accuracy, in order to avoid the relative displacement of the center pin, the marking pin and the inspection fixture bracket, resulting in the accumulation of positioning deviations and affecting the positioning accuracy, the first limiting structure limits the sliding of the marking pin in the mounting hole and the axial rotation around the mounting hole, and the second limiting structure limits the first detection section from sliding into the guide hole in the longitudinal direction and limits the axial rotation of the center pin around the mounting hole, so that the center pin, the marking pin and the inspection fixture bracket are relatively fixed and the first detection section can be used as a positioning end to maintain the state of extending out of the guide hole, realizing the positioning pin function. The detection pin assembly has three functions: marking detection, passability detection and positioning. When multiple functions are needed, different functions can be switched without pulling out and replacing. It is easy to use and saves time and effort. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0029] Figure 1 It is a structural schematic diagram of an embodiment of a detection pin assembly of the present invention;

[0030] Figure 2 for Figure 1 Exploded view of the detection pin assembly.

[0031] Description of Figure Numbers:

[0032] Label name Label name 100 Detection pin assembly 32 Handle end 1 Check fixture bracket 321 convex part 11 Mounting holes 4 The first limit structure 12 Long hole 41 Limiting parts 2 Marking pin 411 Connection hole 21 Guide hole 412 Tooth 22 Score end 42 Adjusting bolt 221 Tip of the line 43 Grooves 222 Guide groove 5 The second limiting structure 3 Center pin 51 Card table 31 Detection end 52 Card slot 311 First detection section 53 Spring parts 312 Second detection section 6 Pin Bushing

[0033] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0036] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0037] At present, manual inspection fixtures generally use movable plug-in inspection pins to detect the position of holes on parts. In addition to using through-stop type inspection pins to detect whether the position of the holes is qualified, it is also required to use a marking pin to visually inspect the offset direction and approximate offset of the holes. In the prior art, inspection pins that can be used for both passing inspection and marking are generally used. However, when the part hole is used as a test hole and needs to be a positioning hole for investigation, the diameter of the marking pin is larger than that of the positioning pin, and the diameter of the passing inspection pin is smaller than that of the positioning pin, and the inspection pin cannot realize the positioning pin function.

[0038] In view of this, the present invention proposes a detection pin assembly 100, which has three functions: line detection, passability detection and positioning. Figure 1 to Figure 2 This is an embodiment of the detection pin assembly provided by the present invention. The detection pin assembly 100 will be described below in conjunction with specific drawings.

[0039] Reference Figure 1 to Figure 2The detection pin assembly 100 includes a gauge bracket 1, a marking pin 2 and a center pin 3. The gauge bracket 1 is provided with a mounting hole 11 in the longitudinal direction. The marking pin 2 extends in the longitudinal direction, is slidably penetrated in the mounting hole 11 and can rotate around the axial direction of the mounting hole 11. The marking pin 2 is provided with a guide hole 21 coaxial with the mounting hole 11. The marking pin 2 has a marking end 22, and a marking tip 221 for marking is convexly provided on the end edge of the marking end 22 to detect the position of the part hole. The center pin 3 extends in the longitudinal direction, is slidably penetrated in the guide hole 21 and can rotate around the axial direction of the guide hole 21. The center pin 3 has a detection end 31 and a handle end 32 extending from both ends of the guide hole 21. The detection end 31 is arranged corresponding to the marking end 22, and the detection end 31 includes a detection end 31 away from the handle end 32. The first detection section 311 and the second detection section 312 are sequentially arranged upward, the cross section of the first detection section 311 is larger than the cross section of the second detection section 312 to form a step, the first detection section 311 is used to cooperate with the part hole for positioning, and the second detection section 312 is used to detect the passability of the part hole, the detection pin assembly 100 also includes a first limiting structure 4 and a second limiting structure 5, when the center pin 3 slides in the guide hole 21 until the first detection section 311 extends out of the guide hole 21 from the marking end 22, the first limiting structure 4 limits the marking pin 2 from sliding in the mounting hole 11 and axially rotating around the mounting hole 11, the second limiting structure 5 limits the first detection section 311 from sliding into the guide hole 21 in the longitudinal direction and limits the center pin 3 from axially rotating around the mounting hole 11.

[0040] In the technical solution of the present invention, the center pin 3 can slide longitudinally relative to the marking pin 2 and rotate axially around the guide hole 21. When it is necessary to detect the passability of the part hole, the center pin 3 is operated by the handle end 32 to slide longitudinally until the second detection section 312 passes through the part hole; when it is necessary to detect the position of the part hole, the center pin 3 or the marking pin 2 is operated, and the marking pin 2 is rotated so that the marking tip 221 draws a circle on the part surface corresponding to the part hole, and the offset direction and offset amount of the circle and the part hole are observed; when the part hole needs to be used as a positioning hole, the center pin 3 slides in the guide hole 21 to the first detection section 312 When the segment 311 extends out of the guide hole 21 from the marking end 22, the cross section of the first detection segment 311 is larger than the second detection segment 312, so as to fit the part hole for positioning. At this time, because the positioning pin requires a high position accuracy, in order to avoid the relative displacement of the center pin 3, the marking pin 2 and the inspection fixture bracket 1, resulting in the accumulation of positioning deviations and affecting the positioning accuracy, the first limiting structure 4 limits the sliding of the marking pin 2 in the mounting hole 11 and the axial rotation around the mounting hole 11, and the second limiting structure 5 limits the first detection segment 311 from sliding into the guide hole 21 in the longitudinal direction and the axial rotation of the center pin 3 around the mounting hole 11. The center pin 3, the marking pin 2 and the inspection fixture bracket 1 are relatively fixed, and the first detection segment 311 can be used as a positioning end to maintain the state of extending out of the guide hole 21, so as to realize the positioning pin function. The detection pin assembly 100 has three functions: marking detection, passability detection and positioning. When multiple functions are needed, different functions can be switched without pulling out and replacing, which is convenient to use and saves time and effort.

[0041] In order to satisfy the switching of the detection pin assembly 100 between the three functions of marking detection, passability detection and positioning, the first limiting structure 4 includes a limiting member 41 provided on the inspection fixture bracket 1, and the limiting member 41 can move in the direction of approaching and moving away from the marking pin 2. When the limiting member 41 approaches the marking pin 2, it can limit the sliding of the marking pin 2 in the mounting hole 11 and the axial rotation around the mounting hole 11. When the part hole needs to be used as a positioning hole, the limiting member 41 approaches the marking pin 2 for limiting. When the part hole is not used as a positioning hole, the positioning function is not required, and the limiting member 41 moves away from the marking pin 2 to release the limiting.

[0042] In order to satisfy that the position-limiting member 41 can move in the direction of approaching and moving away from the marking pin 2, in this embodiment, the inspection fixture bracket 1 is provided with an elongated hole 12 that is longitudinally penetrated, and the length direction of the elongated hole 12 is set to extend in the transverse direction. The position-limiting member 41 extends in the transverse direction, and one end can be clamped with the marking pin 2, and the other end is penetrated with a longitudinally extending connecting hole 411. The first position-limiting structure 4 also includes an adjusting bolt 42 that extends in the longitudinal direction, passes through the elongated hole 12, and is locked in the connecting hole 411. When the position-limiting member 41 needs to move, the adjusting bolt 42 is adjusted to separate from the connecting hole 411 to unlock the position-limiting member 41. After the position-limiting member 41 moves in the transverse direction, the adjusting bolt 42 passes through the elongated hole 12 to the corresponding connecting hole 411, and is locked with the connecting hole 411 to lock the position-limiting member 41. The specific setting that satisfies the movement of the limit member 41 in the direction approaching and moving away from the marking pin 2 is not limited. In other embodiments, one end of the limit member 41 can be rotatably installed on the inspection fixture bracket 1 along the longitudinal axis, and the other end can be rotated to be engaged with the marking pin 2. The limit member 41 is rotated in the direction approaching and moving away from the marking pin 2 to achieve the two states of limiting and unlocking the marking pin 2.

[0043] The specific setting of the limiting member 41 for limiting the marking pin 2 is not limited. In one embodiment, the limiting member 41 and the marking pin 2 are provided with screw holes correspondingly. When the limiting member 41 is close to the marking pin 2, it is fixed and tightened by a screw to limit the marking pin 2. However, the screw needs to be adjusted during limiting, and the screw may contact or even damage the center pin 3. In another embodiment, the limiting member 41 and the marking pin 2 may be provided with magnetic parts that attract each other. However, the limiting by the magnetic part is unstable and easy to fall off. In this embodiment, please refer to Figure 2 The first limiting structure 4 also includes a groove 43, which is arranged along the circumference of the marking pin 2. The limiting member 41 is formed with a plurality of latching teeth 412 that can be latched with the groove 43 at one end close to the marking pin 2. When the limiting member 41 is close to the marking pin 2, it is latched with the groove 43 through the latching teeth 412. The latching teeth 412 abut against the groove wall in the longitudinal direction of the groove 43 to limit the sliding of the marking pin 2 relative to the inspection fixture bracket 1 in the longitudinal direction. The structure is simple and the limiting position is stable, and it is not easy to fall off.

[0044] In order to ensure that the center pin 3 does not slide relative to the marking pin 2 until the first detection section 311 enters the guide hole 21, making the positioning invalid when the positioning pin function is used, the second limiting structure 5 includes a card platform 51 and a card slot 52. The card platform 51 is protruded on the outside of the first detection section 311, and the card slot 52 is provided on the inner side wall of the guide hole 21 and passes through the end surface of the marking end 22. When the positioning pin function is used, the first detection section 311 extends out of the guide hole 21 from the marking end 22, and the card platform 51 is connected to the card slot 52 to limit the first detection section 311 from sliding into the guide hole 21 in the longitudinal direction and to limit the axial rotation of the center pin 3 around the mounting hole 11, thereby maintaining the positioning state of the first detection section 311 extending out of the guide hole 21 from the marking end 22. Since the card platform 51 is provided on the outside of the first detection section 311, when the detection pin assembly 100 needs to switch to the passability detection or marking detection function, the first detection section 311 needs to enter the guide hole 21. At this time, the card platform 51 will interfere with the marking pin 2. In order to avoid interference and affect the use of various functions of the detection pin assembly 100, the inner side wall of the guide hole 21 is also provided with a guide groove 222 extending along the longitudinal direction, and the guide groove 222 is set through the end face of the marking end 22 to be slidably connected with the card platform 51, so that the first detection section 311 can slide into the guide hole 21 along the longitudinal direction, and the guide groove 222 and the card slot 52 are arranged at circumferential intervals along the guide hole 21. When the detection pin assembly 100 needs to switch from the positioning pin state to other states, the card platform 51 of the center pin 3 is operated to disengage from the card slot 52, and the center pin 3 is rotated so that the card platform 51 corresponds to the guide slot 222. At this time, the center pin 3 can slide longitudinally relative to the marking pin 2, and the card platform 51 slides in the guide slot 222 to avoid interference, and the card platform 51 cooperates with the guide slot 222 to guide the center pin 3 to slide longitudinally. The specific settings of the card platform 51 and the guide slot 222 are not limited. In this embodiment, in order to ensure the stability of the positioning of the card platform 51 and the card slot 52, the first detection section 311 is circumferentially symmetrically provided with two card platforms 51, and the card slot 52 is provided with two corresponding to the card platform 51, so as to symmetrically limit the center pin 3 and avoid the shaking of the marking pin 2 relative to the center pin 3, which affects the positioning accuracy. In this embodiment, the guide slot 222 is provided with two corresponding to the card platform 51. Obviously, in one embodiment, a card platform 51 is provided on the outside of the first detection section 311, and one of the card slots 52 and the guide groove 222 is provided accordingly. The number of the card platform 51, the card slots 52 and the guide grooves 222 does not need to correspond one to one, and the number of the card slots 52 and the guide grooves 222 is not less than that of the card platform 51, and the position is set to correspond to the card platform 51.

[0045] Furthermore, when used as a positioning pin, in order to prevent the marking pin 2 from sliding relative to the center pin 3 toward the handle end 32 and affecting the positioning effect, the second limiting structure 5 also includes a spring member 53 extending longitudinally, and the spring member 53 is sleeved on the center pin 3, one end of which is connected to the handle end 32, and the other end is abutted against the marking pin 2. When the clamping platform 51 is clamped with the clamping groove 52, the spring member 53 is in a compressed state to push the marking pin 2 in the longitudinal direction, further providing a locking force for the clamping platform 51 and the clamping groove 52, limiting the sliding of the center pin 3 relative to the marking pin 2 in the longitudinal direction, and limiting the shaking between the marking pin 2 and the center pin 3, thereby improving the positioning accuracy.

[0046] In order to improve the service life and detection accuracy of the detection pin assembly 100, the detection pin assembly 100 also includes a pin sleeve 6 arranged in the mounting hole 11, and the pin sleeve 6 is slidably sleeved with the marking pin 2. The pin sleeve 6 contacts the marking pin 2 to protect the inspection fixture bracket 1, and avoids wear of the mounting hole 11 of the inspection fixture bracket 1 due to long-term use, ensuring the axial rotation of the marking pin 2 around the mounting hole 11, ensuring the accuracy of the marking pin 2 rotating and marking to detect the position of the part hole. Even if the pin sleeve 6 is worn due to use, the pin sleeve 6 can be directly replaced, reducing the maintenance and replacement of the detection pin assembly 100 and reducing costs. Furthermore, the pin sleeve 6 is arranged in the mounting hole 11 by interference fit, so that the pin sleeve 6 is fixed more firmly.

[0047] See also Figure 1 , the handle end 32 of the center pin 3 is provided with a convex portion 321 protruding toward its circumferential side, and the specific setting of the convex portion 321 is not limited, and the shape and size are not limited. In this embodiment, the convex portion 321 includes a handle ball, and in other embodiments, the convex portion 321 may also include a transversely arranged elliptical cylinder. The convex portion 321 increases the operating area of ​​the handle end 32, which is convenient for the operator to operate by hand and increases the comfort of operation. Since the convex portion 321 is convexly arranged on the circumferential side of the handle end 32, the handle end 32 can be restricted from entering the guide hole 21 when the marking pin 2 and the center pin 3 slide relative to each other in the longitudinal direction, causing the center pin 3 to be separated from the marking pin 2. It is worth mentioning that in this embodiment, since the convex portion 321 and the spring member 53 are provided at the same time, one end of the spring member 53 abuts against the marking pin 2, and the other end can directly abut against the convex portion 321, which facilitates the disassembly, assembly and replacement of the detection pin assembly 100.

[0048] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A detection pin assembly, characterized in that: include: The inspection fixture bracket is provided with mounting holes along the longitudinal direction; A marking pin extends longitudinally, is slidably disposed in the mounting hole and can rotate around the axial direction of the mounting hole, the marking pin is provided with a guide hole coaxial with the mounting hole, the marking pin has a marking end, and a marking tip for marking is convexly disposed on the end edge of the marking end, so as to detect the position of the part hole; and A center pin extends longitudinally, is slidably inserted into the guide hole and can rotate around the axial direction of the guide hole, the center pin has a detection end and a handle end extending from both ends of the guide hole, the detection end is arranged corresponding to the marking end, the detection end includes a first detection section and a second detection section sequentially arranged in a direction away from the handle end, the cross section of the first detection section is larger than the cross section of the second detection section to form a step, the first detection section is used to cooperate with the part hole for positioning, and the second detection section is used to detect the passability of the part hole; In which, the detection pin assembly also includes a first limiting structure and a second limiting structure. When the center pin slides in the guide hole until the first detection section extends out of the guide hole from the marking end, the first limiting structure limits the marking pin from sliding in the mounting hole and axially rotating around the mounting hole, and the second limiting structure limits the first detection section from sliding into the guide hole in the longitudinal direction and limits the center pin from axially rotating around the mounting hole.

2. The detection pin assembly according to claim 1, characterized in that: The first limiting structure comprises a limiting member provided on the inspection tool support, and the limiting member can move in a direction close to and away from the marking pin; When the limiting member is close to the marking pin, the marking pin can be restricted from sliding in the mounting hole and rotating around the axial direction of the mounting hole.

3. The detection pin assembly according to claim 2, characterized in that: The inspection tool bracket is provided with an elongated hole which is longitudinally penetrated, and the length direction of the elongated hole is arranged to extend in the transverse direction; The limiting member extends in the transverse direction, one end of which can be clamped with the marking pin, and the other end of which is provided with a connecting hole extending in the longitudinal direction; The first limiting structure also includes an adjusting bolt extending in the longitudinal direction, passing through the elongated hole, and locked in the connecting hole.

4. The detection pin assembly according to claim 2, characterized in that: The first limiting structure further comprises a groove, which is arranged along the circumference of the scribing pin; A plurality of locking teeth which can be locked with the groove are formed on one end of the limiting member close to the marking pin.

5. The detection pin assembly according to claim 1, characterized in that: The second limiting structure comprises: A card platform is convexly arranged outside the first detection section; and A clamping groove, provided on the inner side wall of the guide hole and penetrating the end surface of the scribed end, so as to clamp the clamping platform, restrict the first detection section from sliding into the guide hole in the longitudinal direction and restrict the center pin from rotating axially around the mounting hole; The inner side wall of the guide hole is further provided with a guide groove extending in the longitudinal direction, and the guide groove is arranged through the end surface of the marking end to be slidably connected with the card table, so that the first detection section can slide into the guide hole in the longitudinal direction; The guide groove and the clamping groove are arranged at intervals along the circumference of the guide hole.

6. The detection pin assembly according to claim 5, characterized in that: The second limiting structure further includes a spring member extending in the longitudinal direction, wherein the spring member is sleeved with the center pin, one end of the spring member is connected to the handle end, and the other end of the spring member is in contact with the marking pin; When the card platform is engaged with the card slot, the spring element is in a compressed state.

7. The detection pin assembly according to claim 1, characterized in that: The detection pin assembly also includes a pin sleeve arranged in the mounting hole, and the pin sleeve is slidably sleeved with the marking pin.

8. The detection pin assembly according to claim 7, characterized in that: The pin sleeve is arranged in the mounting hole through interference fit.

9. The detection pin assembly according to claim 1, characterized in that: The handle end of the center pin is provided with a convex portion protruding toward the peripheral side thereof.

10. The detection pin assembly according to claim 9, characterized in that: The protrusion includes a handle ball.

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