High-precision positioning assembly and automatic positioning device

Abstract

The utility model relates to the technical field of mechanical positioning, and particularly discloses a high-precision positioning assembly which comprises a positioning pin capable of moving and used for being inserted into a positioned hole and a positioning seat with a guide hole, the positioning pin is connected in the guide hole in a sliding mode, and at least two elastic blocks distributed in the circumferential direction are arranged at the end, away from the positioning hole, of the positioning pin. The tensioning device further comprises a step-shaped driving rod and a tensioning block arranged on the driving rod in a sleeving mode, the tensioning block and the elastic block can be matched through a wedge face or a conical face, the elastic block is located on the outer side of the tensioning block in the circumferential direction, the driving rod is used for pushing the positioning pin to move, the tensioning block is coaxial with the guide hole and the positioning pin, and after the tensioning block expands the elastic block, the periphery of the elastic block abuts against the guide hole. The automatic positioning device comprises the high-precision positioning assembly and further comprises a driver, and the driver is used for driving the driving rod to move. The scheme is used for solving the problem that the positioning precision is difficult to ensure due to a gap between the positioning pin and the positioning seat.

Description

Technical Field

[0001] The utility model relates to the technical field of mechanical positioning, in particular to a high-precision positioning component and an automatic positioning device. Background Art

[0002] Locating pins are used for positioning during machining or positioning of products during use. For example, when machining requires rotating the workpiece mounted on the chuck to different angles for processing, positioning is required after each angle rotation. For example, the workpiece on the chuck needs to be positioned and processed every time it rotates 60°. The chuck needs to be rotated 6 times and positioned 6 times to complete the workpiece processing. Under normal circumstances, 6 positioning holes are opened on the chuck, and the positioning pins are inserted into the corresponding positioning holes to complete the positioning. For example, when a certain device is in use, it needs to be rotated to different angles for use, and it also needs to be positioned after each rotation to the required angle. During positioning, positioning holes are also set on the positioned part, and the positioning pins will move along the guide holes on the positioning seat and be inserted into the positioning holes to achieve positioning.

[0003] In situations where the positioning accuracy requirements are not high, positioning can be achieved as long as the locating pin can be inserted into the locating hole. This type of positioning method includes manually operated positioning methods, such as the "adjustable positioner" with patent publication number CN103831635A. By screwing the locking nut connected to the positioning shaft, the positioning shaft can be controlled to rotate and move while being inserted into the positioning hole to complete the positioning; there are also electrically controlled or hydraulically controlled positioning structures, such as the "hydraulic-driven groove wheel indexing locating pin type indexing device" with patent announcement number CN202028970U. When the hydraulically driven positioning mechanism needs to position the indexing plate slot that has been rotated into place, it only needs to control the positioning cylinder to start, and the locating pin is inserted into the locating pin hole on the indexing plate to automatically complete the positioning; for example, the "a locating pin type indexing positioning device" with patent announcement number CN217596611U, after the chuck is rotated to the required angle, the patented technology controls the electric drive rod to drive the positioning shaft (also called a locating pin) to be inserted into the positioning hole to complete the positioning.

[0004] However, current positioning devices, whether manual or automatic under electric or hydraulic control, require a positioning seat with a guide hole to guide the movement of the positioning pin (or positioning shaft) in order to improve the positioning accuracy. For example, the sleeve with a guide hole in the aforementioned patented technology (some patents call it a positioning sleeve). However, the fit between the guide hole and the positioning pin is a clearance fit. In applications where extremely high positioning accuracy is required, the gap between the positioning sleeve and the positioning shaft can cause deviations in the positioning shaft position, thereby reducing positioning accuracy. However, if the clearance fit is replaced with an interference fit or transition fit, the smoothness of the positioning pin's movement will be affected, resulting in the current positioning accuracy of the positioning device being difficult to improve. In particular, when the positioned part vibrates during use or machining, the positioning pin may move slightly due to external forces, further affecting positioning accuracy. Utility Model Content

[0005] The utility model aims to provide a high-precision positioning assembly to solve the problem that the positioning accuracy is difficult to ensure due to the gap between the positioning pin and the positioning seat.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A high-precision positioning component includes a positioning pin that can move and is used to be inserted into a positioned hole, a positioning seat with a guide hole, the positioning pin is slidably connected in the guide hole, and the end of the positioning pin away from the positioning hole is provided with at least two circumferentially distributed elastic blocks, and also includes a stepped driving rod and a tightening block mounted on the driving rod, the tightening block and the elastic block can cooperate with each other in wedge surface / conical surface, the elastic block is located on the circumferential outside of the tightening block, the driving rod is used to push the positioning pin to move, the tightening block is coaxial with the guide hole and the positioning pin, and after the tightening block expands the elastic block, the outer periphery of the elastic block is against the guide hole.

[0008] The principle and advantage of this solution are: when adopting this solution, after pushing the positioning pin toward the positioning hole of the positioned part, the tensioning block is pushed to move by the driving rod, and after the tensioning block moves, it pushes the elastic block to open outward, so that the elastic block on the positioning pin is evenly pressed against the guide hole of the positioning seat, thereby eliminating the gap between the positioning pin and the guide hole, ensuring the smooth movement of the positioning pin along the guide hole before and after positioning, and ensuring high-precision positioning after eliminating the gap by tensioning. After tensioning, not only the radial positioning of the positioning pin is achieved, but also the tensioning sets an obstacle for the axial movement of the positioning pin, ensuring that the positioning pin is not prone to radial or axial movement, and also ensuring the accuracy of positioning.

[0009] In addition, the elastic block fits tightly with the guide hole in the positioning seat under the tension of the tension block, so that the outwardly extending positioning pin and the positioning seat form a whole. Even if the positioned part is vibrated by external force, the positioning accuracy of the positioning assembly will not be affected.

[0010] Preferably, as an improvement, the positioning pin and the positioning hole are matched with a conical surface.

[0011] Preferably, as an improvement, the interior of the positioning pin is hollow, one end of the driving rod passes through the positioning pin and the end facing the positioning hole is used for threaded connection with the bottom of the positioning hole.

[0012] Beneficial effect: When this solution is adopted, the driving rod rotates while being inserted into the positioning hole in the process of pushing the positioning pin to gradually insert into the positioning hole. When the driving rod is connected to the positioning hole and the positioning pin is fully inserted into the positioning hole, the elastic block is just against the guide hole. At this time, the positioned part, positioning pin, driving rod, tightening block, and positioning seat are all connected into a whole, realizing the positioning by utilizing the positioning pin and the pressing and tightening of the positioning pin to the positioning hole by utilizing the threaded connection between the driving rod and the bottom of the positioning hole, ensuring that the positioning pin will not rebound after insertion, further guaranteeing the positioning accuracy and anti-interference ability.

[0013] Preferably, as an improvement, a limit stop is fixed on the driving rod, the tensioning block is located between the limit stop and the stepped surface of the driving rod, the free end of the elastic block is fixed with a limit rod, the limit rod faces the driving rod, and the limit rod is used to abut against the end face of the tensioning block.

[0014] Beneficial effect: When this solution is adopted, when the driving rod drives the tightening block to move toward the positioned part to tighten the elastic block, the stepped surface on the driving rod gives the tightening block a thrust, so that the tightening block can expand the elastic block outward and tighten the guide hole, thereby achieving positioning under the elimination of the gap between the positioning pin and the guide hole.

[0015] When the positioning pin needs to be reset, it is only necessary to control the driving rod to reset (that is, move it away from the positioning hole). During the resetting process of the driving rod, the tensioning block is pushed to reset through the limit stopper to loosen the expansion of the elastic block. After the elastic block loses the expansion of the tensioning block, the gap between the elastic block and the guide hole increases, which makes it convenient for the driving rod to drive the positioning pin to move smoothly in the guide hole. At the same time, through the interference between the tensioning block and the limit rod, the positioning pin is driven away from the positioning hole together with the driving rod, thereby realizing the release of the positioning.

[0016] It can be seen that this solution, through the provision of the limit rod and the limit stopper, enables the driver to achieve high-precision positioning and positioning release by moving the drive rod in different directions, and the operation is simple and convenient.

[0017] Preferably, as an improvement, the limit stopper is a limit clamp detachably connected to the drive rod, so that the limit stopper can be replaced after being damaged, and the replacement is simple, convenient and low-cost.

[0018] Preferably, as an improvement, the end of the tensioning block away from the positioning hole is stepped, and a limiting ring is placed on the step of the tensioning block. The limiting ring is used to abut against the limiting rod so that the wear position is transferred from the end face of the tensioning block to the limiting ring, further reducing maintenance costs.

[0019] Preferably, as an improvement, the tensioning block and the positioning pin are ensured not to rotate relative to each other by means of a guide groove and a guide column, the guide groove is parallel to the axis of the driving rod, the guide column is inserted into the guide groove, and one of the guide groove and the guide column is set on the tensioning block and the other is set on the positioning pin.

[0020] The utility model also provides an automatic positioning device, comprising the high-precision positioning assembly and a driver, wherein the driver is used for driving the driving rod to move.

[0021] Beneficial effects: This solution can improve the degree of automation of the positioning device and improve the efficiency of positioning. In addition, for occasions where the positioning device is in a special position and is inconvenient for manual operation, it can completely replace manual operation, thereby breaking the space requirements brought by manual operation and improving positioning efficiency. It can also ensure the consistency of each positioning through the drive of the driver.

[0022] Preferably, as an improvement, the driver includes a driving motor, a driving seat, a fixed seat and a moving component threadedly connected to the fixed seat, the driving motor is used to drive the driving seat to rotate, the driving rod is axially slidingly connected to the driving seat, and the driving rod is used to be inserted into the bottom of the positioning hole and threadedly connected; the moving component includes a nut, a tapered sleeve sleeved in the nut, and an elastic member for pressing the tapered sleeve against the tapered hole in the nut, the nut and the tapered sleeve are coaxial with the driving rod, the nut is threadedly connected in the fixed seat, the tapered sleeve is axially slidingly connected to the driving rod, and a blocking member is also fixed on the driving rod, the blocking member is used to abut against the small-sized end face of the tapered sleeve, and the blocking member and the positioning pin are located on both sides of the nut.

[0023] Beneficial effect: When this solution is adopted, the driver is used to drive the driving rod to rotate with the driving seat. Since a moving assembly is sleeved on the driving rod, when the driving rod needs to drive the positioning pin to move toward the positioning hole, because the nut in the moving assembly is threadedly connected along the fixed seat, and the tapered sleeve in the moving assembly can be axially slidably connected to the driving rod, when the driving rod rotates, the tapered sleeve will rotate synchronously with the driving rod, and the elastic member will press the tapered sleeve against the nut. Therefore, the nut will rotate as a whole with the tapered sleeve under the friction force with the tapered sleeve, and the rotation of the nut will form movement, so that the driving rod is also moved by the whole formed by the nut-tapered sleeve-elastic member, thereby realizing the driving rod rotating and moving under the drive.

[0024] When the nut moves to the end of the fixed sleeve and cannot move, the driving rod has been inserted into the positioning hole due to its rotation and movement. At this time, the driver continues to drive the driving rod to rotate, and the tapered sleeve will idle relative to the nut, while the driving rod continues to move toward the positioning hole. The step on the driving rod pushes the tightening block to tighten the elastic block in the guide hole, completing the positioning and tightening operation. The positioning pin, the positioned part, the driving rod, and the tightening block form a whole, ensuring that the positioning device will not rebound, thereby ensuring positioning accuracy and positioning stability.

[0025] Preferably, as an improvement, a drive sleeve is sleeved on the drive seat, the drive motor drives the drive sleeve to rotate, the drive sleeve and the drive seat are connected by an elastic component, the elastic component includes a radially telescopic spring and a connecting piece located at the end of the spring, the connecting piece has a spherical surface, the spherical surface of the connecting piece is located at the junction of the drive sleeve and the drive seat, the drive seat and the drive sleeve are provided with a receiving groove for accommodating the spherical surface of the connecting piece, and the spring and the connecting piece can be squeezed into the same receiving groove.

[0026] Beneficial effect: When this solution is adopted, when the driving rod does not need to rotate and the driver has not stopped outputting, the driving rod cannot rotate due to the resistance of the moving components or other parts. After the power of the driver is transmitted to the driving sleeve, the driving seat will also be unable to rotate because the driving rod cannot rotate. At this time, the receiving groove on the driving sleeve will give a pushing force to the connecting part, so that the connecting part is completely located in the receiving groove on the side where the spring is located after being squeezed, thereby disconnecting the driving sleeve and the driving seat, avoiding safety problems, and thus forming an overload protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is an axial cross-sectional diagram of the first embodiment of the present invention.

[0028] Figure 2 This is an axial cross-sectional diagram of the second embodiment of the present invention (in this state, the large-diameter end face of the driving rod abuts against the tensioning block to expand the elastic block).

[0029] Figure 3 The second embodiment of the present invention is an axial cross-sectional diagram showing the structure among the moving component, the fixed seat, the driving seat and the driving sleeve.

[0030] Figure 4 It is an axial cross-sectional diagram of the second embodiment of the present invention in the positioning released state.

[0031] Figure 5 The third embodiment of the present invention is a partial axial cross-sectional diagram showing that the shift limiting pin is fixed on the driving rod.

[0032] Figure 6 The third embodiment of the present invention is a partial axial cross-sectional diagram showing that the displacement limiting pin is fixed on the inner hole wall of the tapered sleeve. DETAILED DESCRIPTION

[0033] The following is further described in detail through specific implementation methods:

[0034] The figure marks in the drawings of the specification include: positioned part 10, positioning pin 1, elastic block 11, limiting rod 12, guide groove 13, positioning seat 2, driving rod 3, limiting stopper 31, blocking member 32, tensioning block 4, limiting ring 41, guide column 42, driving machine 5, driving sleeve 51, elastic component 61, connecting part 611, spring 612, accommodating groove 600, driving seat 6, fixed seat 7, moving component 8, nut 81, tapered sleeve 82, elastic member 83, isolation ring 84, limit pin 85, limit groove 86.

[0035] Example 1

[0036] Combine Figure 1 A high-precision positioning assembly includes a positioning pin 1, a positioning seat 2, a driving rod 3 and a tensioning block 4. The specific structure is as follows:

[0037] Positioning pin 1: It is movable and is used to be inserted into the conical positioning hole of the positioning member 10. It includes an integrally formed cylindrical section and a conical section. The conical section of the positioning pin 1 cooperates with the positioning hole with a conical surface. The positioning pin 1 has a hollow structure. The cylindrical section of the positioning pin 1 is integrally processed with a multi-petal elastic block 11. The multi-petal elastic blocks 11 are evenly distributed along the circumference of the positioning pin 1. After the elastic blocks 11 are expanded outward, they can be tightly pressed against the inner wall of the guide hole.

[0038] Positioning seat 2: fixedly installed and provided with a guide hole, the positioning pin 1 is slidably connected in the guide hole, and the elastic block 11 is expanded by the tensioning block 4 and can abut against the inner wall of the guide hole;

[0039] Driving rod 3: used to push the positioning pin 1 to move. The driving rod 3 is a stepped rod. The driving rod 3 includes three integrally formed cylindrical sections of different diameters. The cylindrical section of the driving rod 3 is divided into a small diameter section, a medium diameter section and a large diameter section along the axial direction. The positioning pin 1 is sleeved on the small diameter section (the positioning pin 1 and the driving rod 3 are clearance-fitted). A section of the free end of the small diameter section is provided with a thread. The small diameter section passes through the hollow structure of the positioning pin 1 and is used to be threadedly connected to the bottom of the positioning hole; a limit stopper 31 is fixed on the medium diameter section of the driving rod 3, and the limit stopper 31 is a limit clamp that is detachably connected to the driving rod 3.

[0040] Tension block 4: Sleeved over the medium-diameter section of the drive rod 3, tension block 4 is located between the stopper 31 and the large-diameter section of the drive rod 3, and can engage with the elastic block 11 in a wedge-shaped or conical manner. In this embodiment, the engagement is specifically a conical surface, meaning that tension block 4 is a tensioning cone. Tension block 4 is located within the enclosed area of ​​multiple elastic blocks 11. After tension block 4 tightens elastic block 11, elastic block 11 abuts against the guide hole. The end of tension block 4 away from the positioning hole is stepped, with a limit ring 41 mounted on the step of tension block 4. A limit rod 12 is fixed to the inner side of the free end of elastic block 11, facing the drive rod 3, and is used to abut against the end face of limit ring 41.

[0041] The tensioning block 4 and the positioning pin 1 are ensured not to rotate relative to each other by the guide groove 13 and the guide column 42. The guide groove 13 is axially parallel to the driving rod 3, and the guide column 42 is inserted into the guide groove 13. One of the guide groove 13 and the guide column 42 is set on the tensioning block 4 and the other is set on the positioning pin 1. In this embodiment, the guide column 42 is fixed on the tensioning block 4, and the guide groove 13 is opened on one of the elastic blocks 11 or two adjacent elastic sheets to form the guide groove 13.

[0042] When adopting this embodiment, after pushing the positioning pin 1 toward the positioning hole of the positioned part 10, by designing the length of the driving rod 3, during the process of inserting the positioning pin 1 into the positioning hole, the end of the small diameter section of the driving rod 3 is gradually inserted into the bottom of the positioning hole, and then the positioning pin 1 is driven to gradually approach the positioning hole while the driving rod 3 rotates and moves. At the same time that the positioning pin 1 is in contact with the positioning hole, the tensioning block 4 is also pushed by the end face of the large diameter section of the driving rod 3 to press against the elastic block 11, causing the elastic block 11 to expand, and one end of the positioning pin 1 is positioned in the positioning hole, and the other end of the positioning pin 1 is tightened with the guide hole through the elastic block 11, and the driving rod 3 pressed against the tensioning block 4 is tightened to the bottom of the positioning hole through a threaded connection, thereby ensuring the positioning of eliminating the matching clearance between the positioning hole and the positioning pin 1, and realizing the tightening of the positioning pin 1 by the tensioning block 4, and also ensuring that the entire positioning assembly forms a whole with the positioned part 10 after positioning without rebounding, thereby greatly improving the positioning accuracy.

[0043] In addition, the elastic block 11 fits tightly with the guide hole in the positioning seat 2 under the tension of the tension block 4, so that the outwardly extending positioning pin 1 and the positioning seat 2 form a whole. Even if the positioned part 10 is subjected to external force and vibrates, it will not affect the positioning accuracy of this positioning assembly.

[0044] Example 2

[0045] Combine Figures 2 to 4 The second embodiment provides an automatic positioning device, including the high-precision positioning assembly of the first embodiment, and further including a driver, which is used to drive the driving rod 3 to rotate and move.

[0046] Specifically, the driver includes a driving machine 5, a driving seat 6, a fixed seat 7 and a moving component 8 connected to the internal thread of the fixed seat 7. The driving machine 5 is a motor, which is used to drive the driving seat 6 to rotate. The driving seat 6 is rotatably connected to the fixed seat 7 through a bearing. The driving rod 3 is axially slidably connected to the driving seat 6. Specifically, a strip groove is opened on the large diameter section of the driving rod 3, and a sliding pin is fixed on the driving seat 6. The sliding pin is used to slide in the strip groove.

[0047] The moving assembly 8 includes a nut 81, a tapered sleeve 82 sleeved in the nut 81, and an elastic member 83 for pressing the tapered sleeve 82 against the tapered hole in the nut 81. The nut 81 and the tapered sleeve 82 are coaxial with the drive rod 3. The nut 81 is threadedly connected in the fixed seat 7. The tapered sleeve 82 is axially slidably connected to the drive rod 3. The tapered sleeve 82 cooperates with the conical surface of the nut 81. A blocking member 32 is also fixed on the large diameter section of the drive rod 3. The blocking member 32 is used to abut against the small-sized end face of the tapered sleeve 82. The blocking member 32 and the locating pin 1 are located on both sides of the nut 81. The blocking member 32 is used to abut against the drive seat 6. The end face of the elastic block 11 is opposite to the end face of the nut 81. When the tensioning block 4 is not tightened, the locating pin 1 moves toward the positioning hole direction as the drive rod 3 moves through the abutment between the nut 81 and the end face of the elastic block 11.

[0048] A limiting pin is fixed on the inner wall of the nut 81, and an isolation ring 84 is provided between the limiting pin and the large-sized end face of the tapered sleeve 82. The large-sized end face of the tapered sleeve 82 is provided with a receiving hole. The elastic member 83 that presses the tapered sleeve 82 against the nut 81 includes a sphere and a spring connected to the sphere. The spring is located in the receiving hole, and the spring is used to push the sphere outward until the sphere and the end face of the isolation ring 84 are pressed against each other.

[0049] A driving sleeve 51 is sleeved on the driving seat 6, and the driving machine 5 drives the driving sleeve 51 to rotate. In this embodiment, the output shaft of the driving machine 5 and the driving sleeve 51 are connected by a belt drive, and the driving sleeve 51 and the driving seat 6 are connected by an elastic component 61. The elastic component 61 includes a spring 612 that expands and contracts in the radial direction and a connecting piece 611 connected to the end of the spring 612. The connecting piece 611 has a spherical surface, and the spherical surface of the connecting piece 611 is located at the junction of the driving sleeve 51 and the driving seat 6. The driving seat 6 and the driving sleeve 51 are both provided with a receiving groove 600 for accommodating the spherical surface of the connecting piece 611. The spring 612 can be squeezed into the same receiving groove 600 together with the connecting piece 611; the specific connecting piece 611 is a metal ball, the number of elastic components 61 is at least 2, and all elastic components 61 are evenly distributed circumferentially about the driving seat 6. In this embodiment, the spring 612 of the elastic component 61 is located in the receiving groove 600 in the driving seat 6.

[0050] When this embodiment is used, the positioning method of the automatic positioning device is as follows:

[0051] S1. Insertion and positioning: control the positioning pin 1 to be inserted into the positioning hole, and then control the tightening block 4 to continue to move toward the positioning hole to expand the elastic block 11. The elastic block 11 tightens the guide hole, and the positioning is completed.

[0052] The specific insertion positioning is divided into the following steps:

[0053] S11. In the initial state, the positioning pin 1 is away from the positioning hole, the driving rod 3 has not extended into the positioning hole, and the moving component 8 is close to the side of the fixed seat 7 away from the positioning hole; at this time, the driving motor 5 is started, the driving motor 5 is started, the driving sleeve 51 is driven, and the driving sleeve 51 drives the driving seat 6 to rotate under the connection of the elastic component 61. After the driving seat 6 rotates, the driving rod 3 rotates accordingly.

[0054] S12. Movement of the driving rod 3 before it is inserted into the bottom of the positioning hole: After the driving rod 3 rotates, the moving assembly 8 is sleeved on the driving rod 3, and the sliding connection between the tapered sleeve 82 and the driving rod 3 causes the tapered sleeve 82 and the driving rod 3 to rotate synchronously. The tapered sleeve 82 is pressed against the nut 81 by the elastic member 83, so the nut 81 and the tapered sleeve 82 rotate as a whole. The rotation of the nut 81 is along the fixed seat 7, so the moving assembly 8 realizes movement while rotating, and the driving rod 3 also moves while rotating. Under this action, the positioning pin 1 and the driving rod 3 continue to approach the positioning hole, and the small diameter section of the driving rod 3 is gradually inserted into the bottom of the positioning hole in a rotational movement manner.

[0055] S13. When the locating pin 1 just contacts the conical surface of the locating hole, the elastic block 11 has not been tightened yet. At this time, the driving rod 3 still has space to move toward the side of the locating hole. The nut 81 will no longer rotate continuously because it is against the end face of the locating pin 1 or has moved to the end of the stroke of the fixed seat 7. At this time, the driving motor 5 continues to start, and the driving rod 3 continues to rotate and move. The tapered sleeve 82 idles relative to the nut 81. The continuous movement of the driving rod 3 causes the large diameter section of the driving rod 3 to press against the tightening block 4 and move toward the locating hole, so that the tightening block 4 expands the elastic block 11, and the elastic block 11 presses against the guide hole. The gap between the locating pin 1 and the guide hole is eliminated, and the positioning is completed.

[0056] In the positioning of this embodiment, after positioning is completed, the positioned member 10, the positioning pin 1 and the driving rod 3 form a whole, thereby ensuring positioning accuracy and ensuring anti-interference ability after positioning.

[0057] To release the positioning, the driving motor 5 only needs to be controlled to rotate in the opposite direction to enable the driving rod 3 to drive the positioning pin 1 out of the positioning hole. Specifically, the driving motor 5 drives the driving rod 3 to move away from the positioning hole, and the limit stopper 31 drives the tensioning block 4 to move away from the positioning hole, thereby releasing the expansion of the elastic block 11. The elastic block 11 releases the tension on the guide hole, facilitating the smooth movement of the positioning pin 1 in the guide hole. The driving rod 3 continues to move away from the positioning hole until the driving rod 3 is completely disengaged from the threaded connection with the bottom of the positioning hole. The driving rod 3 will continue to rotate and move under the action of the moving assembly 8 until the automatic positioning device completely exits the positioning hole.

[0058] Example 3

[0059] The third embodiment is further improved on the basis of the second embodiment, as follows:

[0060] In order to avoid excessive wear of the nut 81 and the tapered sleeve 82 at the fitting position caused by the friction when the tapered sleeve 82 is idling relative to the nut 81, a limiting structure is set between the tapered sleeve 82 and the drive rod 3. The limiting structure includes a limiting groove 86 and a limiting pin 85. The limiting pin 85 slides in the limiting groove 86. The limiting groove 86 is axially parallel to the drive rod 3. One of the limiting groove 86 and the limiting pin 85 is set on the large diameter section of the drive rod 3, and the other is set on the inner surface of the tapered sleeve 82.

[0061] Combine Figure 5 The limit pin 85 is fixed on the large diameter section of the driving rod 3, and the limit groove 86 is opened on the inner hole wall of the tapered sleeve 82. When the nut 81 moves to the stroke end of the fixing seat 7 close to the positioning hole, the nut 81 no longer continues to be screwed and moved, and the driving rod 3 continues to rotate and move down (at this time the driving rod 3 has been inserted into the bottom of the positioning hole). The limit pin 85 abuts against the groove wall of the limit groove 86 close to the positioning hole, and pushes the tapered sleeve 82 to overcome the elastic force of the elastic member 83 and continue to rotate and move with the driving rod 3. The tapered sleeve 82 will be disengaged from the abutment with the nut 81, and then ensure that the driving rod 3 continues to move toward the positioning hole to ensure that the tensioning block 4 can expand the elastic block 11, and there will be no excessive friction between the tapered sleeve 82 and the nut 81, which helps to improve the service life of both.

[0062] Combine Figure 6 The limiting pin 85 is fixed on the inner hole wall of the tapered sleeve 82, and a limiting groove 86 is processed on the large diameter section of the driving rod 3. The groove wall of the limiting groove 86 away from the positioning hole can be in contact with the limiting pin 85 when the driving rod 3 continues to rotate and move while the nut 81 no longer moves. Then, the groove wall of the limiting groove 86 pushes the tapered sleeve 82 to rotate and move synchronously with the driving rod 3 and overcome the elastic force of the elastic member 83 to disengage from the nut 81, thereby reducing the friction on the conical surface and improving the service life of the tapered sleeve 82 and the nut 81.

[0063] The above description is merely an embodiment of the present invention, and the commonly known specific technical solutions and / or features of the solution are not described in detail here. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be considered as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection claimed in this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A high-precision positioning assembly, comprising a movable positioning pin for inserting into a positioning hole, and a positioning seat with a guide hole, wherein the positioning pin is slidably connected to the guide hole, characterized in that: The locating pin is provided with at least two circumferentially distributed elastic blocks at one end away from the locating hole, and also includes a stepped driving rod and a tightening block mounted on the driving rod. The tightening block and the elastic block can cooperate with each other in a wedge surface / conical surface. The elastic block is located on the circumferential outside of the tightening block. The driving rod is used to push the locating pin to move. The tightening block is coaxial with the guide hole and the locating pin. After the tightening block expands the elastic block, the outer periphery of the elastic block is against the guide hole.

2. A high-precision positioning assembly according to claim 1, characterized in that: The positioning pin and the positioning hole are matched with each other through a conical surface.

3. The high-precision positioning assembly according to claim 1, characterized in that: The interior of the positioning pin is hollow, and one end of the driving rod passes through the positioning pin and the end facing the positioning hole is used for threaded connection with the bottom of the positioning hole.

4. The high-precision positioning assembly according to claim 1, characterized in that: A limit stop is fixed on the driving rod, and the tensioning block is located between the limit stop and the stepped surface of the driving rod. The free end of the elastic block is fixed with a limit rod, which faces the driving rod and is used to abut against the end face of the tensioning block.

5. The high-precision positioning assembly according to claim 4, characterized in that: The limit stopper is a limit clamping ring detachably connected to the driving rod.

6. The high-precision positioning assembly according to claim 4, characterized in that: One end of the tensioning block away from the positioning hole is in a stepped shape, and a limiting ring is sleeved on the step of the tensioning block. The limiting ring is used to abut against the limiting insertion rod.

7. The high-precision positioning assembly according to claim 1, characterized in that: The tensioning block and the positioning pin are ensured not to rotate relative to each other by the guide groove and the guide column. The guide groove is parallel to the axis of the driving rod. The guide column is inserted into the guide groove. One of the guide groove and the guide column is set on the tensioning block and the other is set on the positioning pin.

8. An automatic positioning device, characterized in that: It comprises the high-precision positioning assembly according to any one of claims 1 to 7, and further comprises a driver for driving the driving rod to move.

9. The automatic positioning device according to claim 8, characterized in that: The driver includes a driving motor, a driving seat, a fixed seat and a moving component connected to the fixed seat through a thread. The driving motor is used to drive the driving seat to rotate, the driving rod is axially slidingly connected to the driving seat, and the driving rod is used to be inserted into the bottom of the positioning hole and threadedly connected; the moving component includes a nut, a tapered sleeve sleeved in the nut, and an elastic member used to press the tapered sleeve against the tapered hole in the nut. The nut and the tapered sleeve are coaxial with the driving rod, the nut is threadedly connected in the fixed seat, the tapered sleeve is axially slidingly connected to the driving rod, and a blocking member is also fixed on the driving rod. The blocking member is used to press against the small-sized end face of the tapered sleeve, and the blocking member and the positioning pin are located on both sides of the nut.

10. The automatic positioning device according to claim 9, characterized in that: The driving seat is covered with a driving sleeve, and the driving motor drives the driving sleeve to rotate. The driving sleeve and the driving seat are connected by an elastic component. The elastic component includes a spring that expands and contracts radially and a connecting piece located at the end of the spring. The connecting piece has a spherical surface, and the spherical surface of the connecting piece is located at the junction of the driving sleeve and the driving seat. Both the driving seat and the driving sleeve are provided with a receiving groove for accommodating the spherical surface of the connecting piece. The spring and the connecting piece can be squeezed into the same receiving groove.

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