Overload protection assembly and positioning device

Abstract

The utility model relates to the technical field of mechanical positioning, in particular to an overload protection assembly which comprises a driving rod used for pushing a hollow positioning pin to move, a driving machine, a driving seat and a driving sleeve, the end, penetrating through the positioning pin, of the driving rod is used for being in threaded connection with the bottom of a positioning hole, and the driving rod is axially connected to the driving seat in a sliding mode. The driving machine drives the driving sleeve to rotate, the driving sleeve sleeves the driving seat, the driving sleeve and the driving seat are connected through an elastic assembly, the elastic assembly comprises a spring and a connecting piece, the connecting piece is provided with a spherical surface, the spherical surface of the connecting piece is located at the junction of the driving sleeve and the driving seat, and the driving seat and the driving sleeve are each provided with a containing groove used for containing the spherical surface of the connecting piece. The spring and the connecting piece can be extruded into the same containing groove. The positioning device comprises a hollow positioning pin and further comprises the overload protection assembly. According to the scheme, the overload problem needing to be solved in the mode that a positioning pin is pushed to conduct positioning in the mode of rotating and moving at the same time is solved.

Description

Technical Field

[0001] This utility model relates to the field of mechanical positioning technology, specifically to an overload protection component and positioning device. Background Technology

[0002] Positioning pins are used for positioning during machining or product use. For example, when machining a workpiece mounted on a chuck, it needs to be rotated to different angles for processing. Positioning is required after each rotation. If the workpiece needs to be positioned and processed every 60°, the chuck needs to rotate 6 times and be positioned 6 times to complete the machining. Typically, 6 positioning holes are made on the chuck, and positioning pins are inserted into the corresponding positioning holes to complete the positioning. Similarly, when a piece of equipment needs to be rotated to different angles for use, positioning is also required after each rotation to the required angle. Positioning is also done by setting positioning holes on the workpiece being positioned, and positioning pins move along the guide holes on the positioning seat and insert into the positioning holes to achieve positioning.

[0003] In applications where high positioning accuracy is not required, positioning can be achieved simply by inserting the positioning pin into the positioning hole. This type of positioning can be manual, such as the "Adjustable Positioner" in patent publication number CN103831635A, where tightening the locking nut connected to the positioning shaft controls the positioning shaft to rotate and move, thus inserting it into the positioning hole to complete the positioning. There are also electrically or hydraulically controlled positioning structures, such as the "Positioning Pin Type Indexing Device for Hydraulically Driven Grooved Wheel Indexing" in patent publication number CN202028970U. This hydraulically driven positioning mechanism, when positioning the indexing plate groove that has rotated to the desired position, only requires controlling the positioning cylinder to start, and the positioning pin inserts into the positioning pin hole on the indexing plate to automatically complete the positioning. Another example is the "Positioning Pin Type Indexing Positioning Device" in patent publication number CN217596611U, which, after the chuck rotates to the required angle, controls the electric drive rod to drive the positioning shaft (also called the positioning pin) into the positioning hole to complete the positioning.

[0004] In current positioning structures, the positioning holes are all deep. If the positioning pin is inserted too deeply, it will cause overload, damaging the positioned part or the positioning structure. In severe cases, it may even pose a safety hazard. Therefore, the overload problem is very important. The current conventional operation is to ensure that the positioning pin is not over-inserted by precisely controlling the movement stroke of the positioning pin, while also taking into account the positioning capability of the positioning pin. Within the depth of the positioning hole, the more the positioning pin is inserted, the better the positioning strength. Especially when the positioning pin and the positioning hole are in a conical fit, only when the positioning pin abuts against the conical surface of the positioning hole can the positioning accuracy be improved. However, this also requires a high degree of precision in the movement distance of the positioning pin and high requirements for hydraulic or electric control, which increases the difficulty of debugging.

[0005] Furthermore, current positioning structures all rely on single-sided insertion and tightening, lacking a method that utilizes the strength of the positioned component itself to tighten and prevent the positioning pin from springing back. The inventor proposes a positioning pin with a hollow structure. In use, the hollow positioning pin is used in conjunction with a stepped drive rod. The drive rod, fitted with the positioning pin, moves towards the positioning hole, causing the hollow positioning pin to insert into the positioning hole. After the positioning pin is in contact with the positioning hole, the drive rod is screwed on, allowing one end of the drive rod, which passes through the positioning pin, to connect with a threaded hole at the bottom of the positioning hole. This achieves the function of tightening the positioning pin onto the positioned component via the drive rod, preventing the positioning pin from springing back after positioning. However, the current design of the drive rod, which can both move and rotate, also needs to consider the overload problem caused by excessive movement. Utility Model Content

[0006] The present invention aims to provide an overload protection component to solve the overload problem that needs to be addressed in the method of positioning by pushing the positioning pin while rotating and moving.

[0007] The drive rod has an overload problem when it is positioned against the positioning pin.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An overload protection component includes a drive rod for pushing a hollow locating pin to move. One end of the drive rod passes through the locating pin and is threaded to the bottom of a locating hole. The component also includes a drive motor, a drive base, and a drive sleeve. The drive rod is axially slidably connected to the drive base. The drive motor drives the drive sleeve to rotate. The drive sleeve is fitted onto the drive base. The drive sleeve and the drive base are connected by an elastic component. The elastic component includes a radially telescopic spring and a connector located at the end of the spring. The connector has a spherical surface located at the junction of the drive sleeve and the drive base. Both the drive base and the drive sleeve are provided with receiving grooves for accommodating the spherical surface of the connector. The spring and the connector can be compressed into the same receiving groove.

[0010] The principle and advantages of this solution are as follows: When the drive rod moves while rotating and then moves to the locating pin and presses against the locating hole, one end of the drive rod is already screwed into the threaded hole at the bottom of the locating hole. If the drive rod continues to rotate and move, it will inevitably cause excessive thrust of the locating pin on the locating hole, resulting in overload. It will also easily cause the thread at the end of the drive rod to deform and strip due to the inability to continue pushing the locating pin. In this solution, when the locating pin moves toward the locating hole, the drive rod rotates and moves under the drive of the drive motor because it is threadedly connected to the bottom of the locating hole. When the locating pin is against the locating hole and cannot be pushed further by the drive rod, the drive rod will stop rotating and moving, and the drive seat will also stop rotating. Under the continued drive of the drive motor, the drive sleeve will squeeze the connector on the elastic component, so that the connector and the spring are completely squeezed into the same receiving groove where the spring is installed. The drive sleeve rotates relative to the drive seat, avoiding the overload problem caused by the continuous input of the drive motor driving force, and realizing overload protection.

[0011] Preferably, as an improvement, a positioning completion switch is provided, which is triggered by the drive rod when the positioning pin completes positioning, and the controller controls the drive motor to stop working after the positioning completion switch is triggered.

[0012] This utility model also provides a positioning device, including a hollow positioning pin, and the overload protection component.

[0013] Preferably, as an improvement, a nut is installed on the drive rod, the nut rotates together with the drive rod, the nut is threaded into the fixed seat, and the nut is coaxial with the drive rod.

[0014] Beneficial effects: Before the drive rod is inserted into the bottom of the positioning hole, it needs to be pushed into the bottom of the positioning hole. This pushing cannot be accomplished by the drive motor, drive base, and drive sleeve alone. However, the presence of the nut in this solution, which can move along the fixed base and rotate with the drive rod, allows the drive rod to rotate and move simultaneously with the cooperation of the nut, as long as the drive rod rotates.

[0015] Preferably, as an improvement, the drive rod is stepped, and a tensioning block is fitted on the drive rod. The tensioning block is located between the locating pin and the nut. The end face of the tensioning block away from the locating pin can be in contact with the stepped surface of the drive rod. At least two elastic blocks are circumferentially distributed at the end of the locating pin facing the tensioning block. The elastic blocks are located on the outer circumference of the tensioning block. The tensioning block is coaxial with the guide hole and the locating pin. After the tensioning block expands and releases the elastic blocks, the outer periphery of the elastic blocks abuts against the guide hole.

[0016] Beneficial effects: When this solution is adopted, after the locating pin is pushed to move towards the locating hole of the locating part, the step surface of the drive rod pushes the tensioning block to move. After the tensioning block moves, it pushes the elastic block to open outward, so that the elastic block on the locating pin is evenly pressed against the guide hole of the locating seat, thereby eliminating the gap between the locating pin and the guide hole, ensuring the smooth movement of the locating pin along the guide hole before and after positioning. The gap is eliminated by tensioning, ensuring high-precision positioning. Moreover, after tensioning, not only is the radial positioning tension of the locating pin achieved, but the axial movement of the locating pin is also set as an obstacle, ensuring that the locating pin is not prone to radial or axial movement, and also ensuring the positioning accuracy.

[0017] Preferably, as an improvement, a tapered sleeve is provided between the nut and the drive rod, the tapered sleeve and the nut can abut against each other on their tapered surfaces, an elastic element is provided between the nut and the tapered sleeve to press the tapered sleeve against the nut, and the tapered sleeve is axially slidably connected to the drive rod.

[0018] Beneficial effects: When the drive rod is not in contact with the bottom thread of the positioning hole, the elastic component connects the drive seat and the drive sleeve, thereby transmitting the rotational power of the drive motor to the drive rod. When the drive rod rotates, the tapered sleeve is pressed against the nut due to the elastic component. The nut and the tapered sleeve will rotate simultaneously. After the nut rotates, it will move along the fixed seat, so that the whole formed by the drive rod, the tapered sleeve and the nut will also move together, realizing the drive rod rotating and moving at the same time.

[0019] When the nut cannot rotate due to moving to the end of the fixed seat's travel, and the drive rod needs to continue pushing the tensioning block to expand the elastic block, the continued rotation of the drive rod will cause the tapered sleeve to rotate synchronously. The tapered sleeve will rotate relative to the nut, thus preventing the entire positioning device from jamming.

[0020] Preferably, as an improvement, a blocking member is also fixed on the drive rod. The blocking member is used to abut against the small-sized end face of the tapered sleeve. The blocking member and the positioning pin are located on both sides of the nut. The blocking member is used to abut against the drive seat.

[0021] Beneficial effects: When using this solution, the blocking component ensures that after the drive rod rotates and moves away from the positioning hole, it stops moving further when the blocking component abuts against the end face of the drive seat. This restricts the drive rod's movement, allowing it to rotate while the tapered sleeve and nut continue to rotate. The nut continues to rotate and moves axially. Once the tapered sleeve can no longer move axially along the drive rod, it will spin relative to the nut, preventing the nut from moving. This ensures that even if the drive rod fails to stop in time, structural jamming is avoided, effectively protecting the drive rod during the reset phase.

[0022] Preferably, as an improvement, a limiting structure is provided between the tapered sleeve and the drive rod. The limiting structure includes a limiting groove and a limiting pin. The limiting pin slides in the limiting groove. The limiting groove is parallel to the axial direction of the drive rod. One of the limiting groove and the limiting pin is provided on the drive rod, and the other is provided on the inner surface of the tapered sleeve.

[0023] Beneficial effects: When the drive rod pushes the tensioning block to move, if the nut stops rotating but the tapered sleeve still rotates synchronously with the drive rod, the limiting structure can push the tapered sleeve to overcome the elastic force of the elastic element and thus disengage from the tapered surface of the nut, reducing the free-spinning friction between the tapered sleeve and the nut, which helps to improve the service life of the nut and the tapered sleeve.

[0024] Preferably, as an improvement, a limit stop is fixed on the drive rod, the tensioning block is located between the limit stop and the stepped surface of the drive rod, and a limit plug is fixed to the free end of the elastic block, the limit plug facing the drive rod, and the limit plug is used to abut against the end face of the tensioning block.

[0025] Beneficial effects: When this solution is adopted, when the drive rod moves the tensioning block toward the positioned part to tension the elastic block, the stepped surface on the drive rod provides a thrust to the tensioning block, so that the tensioning block can expand the elastic block outward and tighten the guide hole, thereby achieving positioning without the gap between the positioning pin and the guide hole.

[0026] When the positioning pin needs to be reset, it is only necessary to control the drive rod to reset (i.e., move away from the positioning hole). During the reset process, the tension block is pushed to reset by the limit stop to release the tension of the elastic block. After the elastic block loses the tension of the tension block, the gap between the elastic block and the guide hole increases, which makes it easier for the drive rod to drive the positioning pin to move smoothly in the guide hole. At the same time, through the abutment between the tension block and the limit rod, the positioning pin is driven away from the positioning hole along with the drive rod, thus realizing the release of the positioning pin.

[0027] As can be seen, this solution, through the setting of limit rods and limit stops, enables the drive motor to achieve high-precision positioning and release of positioning by moving the drive rod in different directions, and the operation is simple and convenient.

[0028] Preferably, as an improvement, the locating pin engages with the tapered surface of the locating hole. Attached Figure Description

[0029] Figure 1 This is a cross-sectional view of Embodiment 1 of the present invention.

[0030] Figure 2 for Figure 1 A sectional view of the overload protection component applied to the positioning device.

[0031] Figure 3 This is a cross-sectional view of Embodiment 2 of the present invention.

[0032] Figure 4 This is a cross-sectional view of the positioning device in Embodiment 3 of this utility model (in this state, the large-diameter end face of the drive rod abuts against the tensioning block to expand the elastic block).

[0033] Figure 5 This is a cross-sectional view of Embodiment 3 of the present invention, showing the connection relationship between the positioning pin, the drive rod and the guide assembly.

[0034] Figure 6 This is a cross-sectional view of Embodiment 3 of the present invention, showing the connection relationship between the drive rod and the moving component.

[0035] Figure 7 This is a cross-sectional view of the positioning device in the third embodiment of the present invention after it has been in contact positioning.

[0036] Figure 8 This is a partial axial cross-sectional view of Embodiment 4 of the present invention, showing the limiting pin fixed on the drive rod.

[0037] Figure 9 This is a partial axial cross-sectional view of Embodiment 4 of the present invention, showing the limiting pin fixed on the inner wall of the tapered sleeve. Detailed Implementation

[0038] The following detailed description illustrates the specific implementation method:

[0039] The reference numerals in the accompanying drawings include: 10 for the positioned component, 1 for the positioning pin, 11 for the elastic block, 12 for the limiting rod, 13 for the guide groove, 2 for the positioning seat, 3 for the drive rod, 31 for the limiting stop, 32 for the blocking component, 4 for the tensioning block, 41 for the limiting ring, 42 for the guide post, 5 for the drive motor, 51 for the drive sleeve, 61 for the elastic component, 611 for the connecting component, 612 for the spring, 600 for the receiving groove, 6 for the drive seat, 7 for the fixed seat, 8 for the moving component, 81 for the nut, 82 for the cone sleeve, 83 for the elastic component, 84 for the isolation ring, 85 for the movement limiting pin, 86 for the movement limiting groove, and 100 for the positioning completion switch.

[0040] Example 1

[0041] Combination Figure 1 and Figure 2 An overload protection component includes a drive rod 3 for pushing a hollow positioning pin 1 to move. One end of the drive rod 3 passes through the positioning pin 1 and is threaded to the bottom of the positioning hole. The drive rod 3 is a three-section stepped structure, consisting of three integrally formed cylindrical sections of different diameters. The cylindrical sections of the drive rod 3 are divided into a small diameter section, a medium diameter section, and a large diameter section along the axial direction. The small diameter section of the drive rod 3 passes through the hollow structure of the positioning pin 1 and is threaded to the bottom of the positioning hole on the positioned part 10.

[0042] It also includes a drive motor 5, a drive base 6, and a drive sleeve 51. The drive motor 5 is fixedly installed and can be an electric motor. The drive motor 5 is used to drive the drive sleeve 51 to rotate. The specific transmission method can be belt drive. The drive sleeve 51 is fitted on the drive base 6. The drive base 6 is rotatably connected to the fixedly installed fixed base 7 through a bearing. The drive rod 3 is axially slidably connected to the drive base 6. Specifically, a strip groove is opened on the large diameter section of the drive rod 3. A sliding pin is fixed on the drive base 6. The sliding pin is used to slide in the strip groove.

[0043] The drive sleeve 51 and the drive seat 6 are connected by an elastic component 61. The elastic component 61 includes a radially extending spring 612 and a connector 611 connected to the end of the spring 612. The connector 611 has a spherical surface, which is located at the junction of the drive sleeve 51 and the drive seat 6. Both the drive seat 6 and the drive sleeve 51 are provided with a receiving groove 600 for accommodating the spherical surface of the connector 611. The spring 612 and the connector 611 can be pressed into the same receiving groove 600. Specifically, the connector 611 is a metal ball. There are at least two elastic components 61. All elastic components 61 are evenly distributed around the drive seat 6. In this embodiment, the spring 612 of the elastic component 61 is located in the receiving groove 600 in the drive seat 6.

[0044] When the drive rod 3 moves while rotating and moves to the positioning pin 1 and then to the positioning hole, one end of the drive rod 3 is screwed into the threaded hole at the bottom of the positioning hole. If the drive rod 3 continues to rotate and move, it will inevitably cause the positioning pin 1 to exert too much force on the positioning hole and cause overload. In this embodiment, when the positioning pin 1 moves toward the positioning hole, the drive rod 3 rotates and moves under the drive of the drive machine 5 because it is threaded to the bottom of the positioning hole. When the positioning pin 1 is against the positioning hole and cannot be pushed by the drive rod 3, the drive rod 3 will stop rotating and moving, and the drive seat 6 will also stop rotating. Under the continued drive of the drive machine 5, the drive sleeve 51 will squeeze the connector 611 on the elastic component 61, so that the connector 611 and the spring 612 are completely squeezed into the receiving groove 600 where the spring 612 is installed. The drive sleeve 51 rotates relative to the drive seat 6, avoiding the continuous input of the driving force of the drive machine 5, thereby avoiding the overload problem.

[0045] Example 2

[0046] Combination Figure 3 The second embodiment is a further improvement on the first embodiment. Specifically, it includes a positioning completion switch 100. When the positioning pin 1 completes positioning, the drive rod 3 triggers the positioning completion switch 100. After the positioning completion switch 100 is triggered, the controller controls the drive motor 5 to stop working, so as to ensure that the drive motor 5 of the overload protection component stops working in time. The positioning completion switch 100 in this embodiment can be an inductive switch or a limit switch.

[0047] Example 3

[0048] Combination Figures 4 to 7 This embodiment provides a positioning device, including a hollow positioning pin 1, an overload protection component of Embodiment 1, a moving component 8 sleeved on a drive rod 3, and a guide component for guiding the movement of the positioning pin 1.

[0049] Combination Figure 5 Positioning pin 1: Movable and inserted into the conical positioning hole of the positioned part 10, comprising an integrally formed cylindrical section and a conical section. The conical section of positioning pin 1 engages with the positioning hole via a conical surface. Positioning pin 1 has a hollow structure and is fitted onto the small-diameter section of the drive rod 3 (positioning pin 1 and drive rod 3 are clearance-fitted). A limit stop 31 is fixed on the middle-diameter section of the drive rod 3. The limit stop 31 is a detachable limit retaining ring connected to the drive rod 3. The cylindrical section of positioning pin 1 is integrally machined with multi-lobed elastic blocks 11, which are evenly distributed along the circumference of positioning pin 1. The elastic blocks 11 can be expanded outward.

[0050] Combination Figure 5 The guide assembly includes a positioning seat 2 with a guide hole and a tensioning block 4 for expanding the elastic block 11 of the positioning pin 1. The positioning seat 2 is fixedly installed, the positioning pin 1 is slidably connected in the guide hole, and the elastic block 11 can abut against the inner wall of the guide hole after being expanded by the tensioning block 4.

[0051] A limiting stop 31 is fixed on the middle diameter section of the drive rod 3. The limiting stop 31 is a limiting retaining ring detachably connected to the drive rod 3. A tensioning block 4 is fitted on the middle diameter section of the drive rod 3. The tensioning block 4 is located between the limiting stop 31 and the large diameter section of the drive rod 3, and can engage with the elastic block 11 on a wedge / conical surface. In this embodiment, it is specifically a conical surface engagement, that is, the tensioning block 4 is a tensioning cone. The tensioning block 4 is located within the enclosed area of ​​multiple elastic blocks 11. After the tensioning block 4 tensions the elastic block 11, the elastic block 11 abuts against the guide hole. The end of the tensioning block 4 away from the positioning hole is stepped. A limiting ring 41 is fitted on the step of the tensioning block 4. A limiting insert 12 is fixed on the inner side of the free end of the elastic block 11. The limiting insert 12 faces the drive rod 3 and is used to abut against the end face of the limiting ring 41.

[0052] The tensioning block 4 and the positioning pin 1 are ensured not to rotate relative to each other by the provided guide groove 13 and guide post 42. The guide groove 13 is parallel to the axis of the drive rod 3. The guide post 42 is inserted into the guide groove 13. One of the guide groove 13 and the guide post 42 is set on the tensioning block 4 and the other is set on the positioning pin 1. In this embodiment, the guide post 42 is fixed on the tensioning block 4. The guide groove 13 is formed on one of the elastic blocks 11 or by two adjacent elastic blocks.

[0053] In this embodiment, the drive rod 3 rotates and moves while driving the positioning pin 1 to be inserted into the positioning hole. After the positioning pin 1 contacts the positioning hole, the drive rod 3 continues to rotate and move, so that the tensioning block 4 is pushed by the stepped surface of the drive rod 3 to expand the elastic block 11. The elastic block 11 is tightened with the guide hole, eliminating the gap between the positioning pin 1 and the guide hole, thereby ensuring high-precision positioning.

[0054] Furthermore, the elastic block 11, under the tension of the tensioning block 4, fits tightly with the guide hole inside the positioning seat 2, making the outwardly protruding positioning pin 1 and the positioning seat 2 form a whole, greatly improving the positioning stability after positioning and ensuring that the positioning device will not rebound. Even if the positioned part 10 is subjected to external force and vibrates, it will not affect the positioning accuracy of this positioning device.

[0055] Combination Figure 6 The moving component 8 includes a nut 81, a tapered sleeve 82, and an elastic element 83 that abuts the tapered sleeve 82 against the nut 81. The drive rod 3 is in the form of a three-section stepped structure. The nut 81 is threadedly connected to the inner hole of the fixed seat 7. The nut 81 and the tapered sleeve 82 are coaxial with the drive rod 3. The nut 81 is threadedly connected inside the fixed seat 7. The tapered sleeve 82 is engaged with the tapered surface of the nut 81. The tapered sleeve 82 is axially slidably connected to the large-diameter section of the drive rod 3. A blocking element 32 is also fixed on the large-diameter section of the drive rod 3. The blocking element 32 is used to abut against the small-sized end face of the tapered sleeve 82. The blocking element 32 and the positioning pin 1 are located on both sides of the nut 81. The blocking element 32 is used to abut against the drive seat 6.

[0056] A limiting pin is fixed on the inner wall of the nut 81. An isolation ring 84 is provided between the limiting pin and the large-size end face of the tapered sleeve 82. The large-size end face of the tapered sleeve 82 is provided with a receiving hole. The elastic element 83 that abuts the tapered sleeve 82 against the nut 81 includes a sliding body and a spring connected to the sliding body. The spring is located in the receiving hole. The spring is used to push the sliding body outward until the sliding body abuts against the end face of the isolation ring 84. In this embodiment, the sliding body is spherical.

[0057] In this embodiment, the rotation of the drive motor 5 drives the drive sleeve 51 to rotate. After the drive sleeve 51 rotates, the rotational power is transmitted to the drive seat 6 through the elastic component 61. After the drive seat 6 rotates, the drive rod 3 is driven to rotate. The conical sleeve 82 on the drive rod 3 rotates with it. The conical sleeve 82 is pressed against the nut 81 by the elastic component 83. Therefore, the nut 81 and the conical sleeve 82 rotate as a whole. The rotation of the nut 81 is along the fixed seat 7. Therefore, the nut 81, the conical sleeve 82 and the drive rod 3 will form a whole and achieve rotation and movement at the same time. That is, the drive rod 3 achieves variable rotation and movement. Under this action, the positioning pin 1 and the drive rod 3 in the positioning device continuously move closer to the positioning hole. The small diameter section of the drive rod 3 is also gradually inserted into the bottom of the positioning hole by rotational movement. The positioning pin 1 is also inserted into the positioning hole.

[0058] When the nut 81 moves to the end of its stroke and stops rotating, if the drive motor 5 is still outputting rotation, the drive rod 3 will continue to rotate because it is threaded to the bottom of the positioning hole. The tapered sleeve 82 will also continue to rotate with the drive rod 3. At this time, the tapered sleeve 82 will rotate freely relative to the nut 81, ensuring that the entire positioning device will not jam. If the drive rod 3, the tapered sleeve 82, and the nut 81 form a whole and stop rotating, the elastic component 61 will play its role. The connector 611 on the elastic component 61 will move into the receiving groove 600 of the drive seat 6, so that the drive sleeve 51 will rotate freely relative to the drive seat 6, which also ensures that the entire positioning device will not be overloaded and jammed, thus protecting the device.

[0059] Example 4

[0060] To prevent excessive wear at the mating position of the nut 81 and the tapered sleeve 82 due to friction when the tapered sleeve 82 rotates relative to the nut 81, a limiting structure is provided 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, which is parallel to the axis of the drive rod 3. One of the limiting groove 86 and the limiting pin 85 is located on the large-diameter section of the drive rod 3, while the other is located on the inner surface of the tapered sleeve 82.

[0061] Combination Figure 8 The limiting pin 85 is fixed on the large-diameter section of the drive rod 3, and the limiting groove 86 is opened on the inner wall of the tapered sleeve 82. When the nut 81 moves to the end of the stroke of the fixed seat 7 near the positioning hole, the nut 81 stops turning and moving, while the drive rod 3 continues to rotate and move down (at this time, the drive rod 3 has been inserted into the bottom of the positioning hole). The limiting pin 85 abuts against the groove wall of the limiting groove 86 near the positioning hole and pushes the tapered sleeve 82 to overcome the elastic force of the elastic element 83 and continue to rotate and move with the drive rod 3. The tapered sleeve 82 will disengage from the nut 81, thereby ensuring that the drive rod 3 continues to move towards the positioning hole so that the tensioning block 4 can expand the elastic block 11. There will also be no excessive friction between the tapered sleeve 82 and the nut 81, which helps to improve the service life of both.

[0062] Combination Figure 9 The limiting pin 85 is fixed on the inner wall of the tapered sleeve 82. The limiting groove 86 is machined on the large diameter section of the drive rod 3. The groove wall of the limiting groove 86, which is far away from the positioning hole, can come into contact with the limiting pin 85 when the drive rod 3 continues to rotate and move while the nut 81 stops moving. Then, the groove wall of the limiting groove 86 pushes the tapered sleeve 82 to rotate and move synchronously with the drive rod 3 and overcomes the elastic force of the elastic element 83 to disengage from the nut 81, reducing the degree of friction on the tapered surface and improving the service life of the tapered sleeve 82 and the nut 81.

[0063] The above descriptions are merely embodiments of this utility model. Commonly known technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. These modifications and improvements should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An overload protection component, characterized in that: The device includes a drive rod for pushing the hollow positioning pin to move. One end of the drive rod passes through the positioning pin and is threaded to the bottom of the positioning hole. It also includes a drive motor, a drive seat, and a drive sleeve. The drive rod is axially slidably connected to the drive seat. The drive motor drives the drive sleeve to rotate. The drive sleeve is fitted onto the drive seat. The drive sleeve and the drive seat are connected by an elastic component. The elastic component includes a radially telescopic spring and a connector located at the end of the spring. The connector has a spherical surface. The spherical surface of the connector is located at the junction of the drive sleeve and the drive seat. Both the drive seat and the drive sleeve are provided with receiving grooves for accommodating the spherical surface of the connector. The spring and the connector can be squeezed into the same receiving groove.

2. The overload protection component according to claim 1, characterized in that: It includes a positioning completion switch. When the positioning pin completes positioning, the drive rod triggers the positioning completion switch. After the positioning completion switch is triggered, the controller controls the drive motor to stop working.

3. A positioning device, comprising a hollow positioning pin, characterized in that: It also includes an overload protection component as described in any one of claims 1-2.

4. A positioning device according to claim 3, characterized in that: A nut is installed on the drive rod, and the nut rotates together with the drive rod. The nut is threaded into the fixed seat, and the nut is coaxial with the drive rod.

5. A positioning device according to claim 4, characterized in that: The drive rod is stepped, and a tensioning block is fitted on the drive rod. The tensioning block is located between the positioning pin and the nut. The end face of the tensioning block away from the positioning pin can be in contact with the stepped surface of the drive rod. At least two elastic blocks are circumferentially distributed on the end of the positioning pin facing the tensioning block. The elastic blocks are located on the outer circumference of the tensioning block. The tensioning block is coaxial with the guide hole and the positioning pin. After the tensioning block expands and releases the elastic blocks, the outer circumference of the elastic blocks abuts against the guide hole.

6. A positioning device according to claim 5, characterized in that: A tapered sleeve is provided between the nut and the drive rod, and the tapered sleeve and the nut can abut against each other on their tapered surfaces. An elastic element is provided between the nut and the tapered sleeve to press the tapered sleeve against the nut. The tapered sleeve is axially slidably connected to the drive rod.

7. A positioning device according to claim 6, characterized in that: The drive rod is also fixed with a blocking component, which is used to abut against the small end face of the tapered sleeve. The blocking component and the positioning pin are located on both sides of the nut, and the blocking component is used to abut against the drive seat.

8. A positioning device according to claim 6, characterized in that: A limiting structure is provided between the tapered sleeve and the drive rod. The limiting structure includes a limiting groove and a limiting pin. The limiting pin slides in the limiting groove. The limiting groove is parallel to the axis of the drive rod. One of the limiting groove and the limiting pin is provided on the drive rod, and the other is provided on the inner surface of the tapered sleeve.

9. A positioning device according to claim 5, characterized in that: A limit stop is fixed on the drive rod, and a tensioning block is located between the limit stop and the stepped surface of the drive rod. A limit plug is fixed to the free end of the elastic block, with the limit plug facing the drive rod and used to abut against the end face of the tensioning block.

10. A positioning device according to any one of claims 4-9, characterized in that: The locating pin engages with the conical surface of the locating hole.

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