A self-locking pin-type torque limiter
By introducing a small steel ball and an arc groove into the pin-type torque limiter, self-locking is achieved using elastic force, which solves the problem of friction on the rear end face of the pin-type torque limiter after disengagement, extends its service life and keeps the torque setting value stable.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING WISDOM TRANSMISSION MASCH CO LTD
- Filing Date
- 2025-06-16
- Publication Date
- 2026-04-17
AI Technical Summary
The existing pin-type torque limiter suffers from torque setpoint drop due to friction on the rear end face after disengagement, and fails after repeated use, requiring readjustment.
Design a self-locking pin-type torque limiter that uses a combination of a small steel ball and an arc groove. The small steel ball is made to slide into the arc groove instantaneously by elastic force, thereby achieving self-locking of the pin and avoiding friction between the large steel ball and the end face.
It effectively prevents end face friction when the torque is overloaded, extends service life, ensures that the torque setting value remains unchanged, and can still be used normally after multiple protections.
Smart Images
Figure CN224135031U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of limiter technology, and in particular to a self-locking pin-type torque limiter. Background Technology
[0002] The pin-type torque limiter is a device used for overload protection of transmission systems and is widely used in transmission equipment.
[0003] The commonly used pin-type torque limiter typically has the pin housing mounted on the flange of the driving end (motor), and the ball joint mounted on the coupling assembly of the driven end (gearbox). In the engaged state, the stacked spring pushes the pressure plate, pressing the slider and causing the push rod to fall into the ball socket, thus rotating the driven end.
[0004] When the passive end is overloaded and the torque exceeds the set torque, the large steel ball runs out of the ball socket, and the slider is squeezed onto the outer circle of the push rod and presses against the outer circle of the push rod, causing the active end and the passive end to disengage and not automatically reset, thus protecting the equipment from damage. When the fault is cleared, applying external force to the rear end of the push rod can reset it to the meshing state shown in the figure.
[0005] Theoretically, when disengaged, there should be no residual torque between the ejector housing and the two end faces of the ball joint. However, in actual use, it was found that after each disengagement, the two end faces actually rub against each other. If the machine is not stopped immediately, the end faces will be rubbed into spherical grooves by the large steel ball. After each reset, the torque will be lower than the original set value. After several repetitions, this torque limiter becomes ineffective, and the torque must be readjusted. Utility Model Content
[0006] Purpose of the utility model: Based on the problems mentioned in the background art, a self-locking pin-type torque limiter is proposed.
[0007] Technical solution: A self-locking pin-type torque limiter, comprising:
[0008] The ejector housing is assembled to the kinetic energy output end; the ejector housing has assembly holes of different diameters inside;
[0009] A ball joint is assembled on the equipment end; a ball groove is formed at the end of the ball joint;
[0010] A push rod is slidably disposed within the mounting hole; a large steel ball is mounted at the end of the push rod, the shape of which is adapted to the spherical groove.
[0011] Its characteristic is that it further includes an elastic component disposed in the assembly hole, and a plurality of small steel balls assembled at the output end of the elastic component;
[0012] The elastic component is used to provide a preset elastic force, so that the push rod is in a preset position inside the inner hole under the action of the elastic force;
[0013] The outer side of the push rod has an arc groove that matches the shape of the small steel ball. When the small steel ball slides into the arc groove, the push rod is subjected to a component of the elastic force away from the spherical groove, thus forming a self-locking mechanism for the current displacement of the push rod.
[0014] In a further embodiment, the inner diameter of the assembly hole increases in a stepped manner along its length direction, and includes at least a first guide hole, a second mounting hole, and an inner inclined surface between the two inner holes, wherein the inner diameter of the first guide hole is the smallest; the small steel ball is pressed against the inner inclined surface under the action of elastic force, and the shape of the inner inclined surface is adapted to the small steel ball.
[0015] In a further embodiment, the diameter of the push rod decreases in a stepped manner along its axial direction, including at least a first outer side and a second outer side; the diameter of the first outer side is the largest, and an outer inclined surface is formed between the two outer sides; the first outer side is adapted to the first guide hole, and the second outer side and the second mounting hole form an assembly area for assembling the elastic element; the small steel ball is pressed against the outer inclined surface under the action of elastic force, and the shape of the outer inclined surface is adapted to the small steel ball.
[0016] In a further embodiment, the resilient component includes at least:
[0017] A stacked spring is disposed within the assembly area and on the outer circumference of the push rod;
[0018] A pressure plate is disposed in the assembly area and located at the output end of the stacked spring; the output end face of the pressure plate is an inclined surface, and the direction line of the force applied to the small steel ball passes through one of the points on the axis of the push rod.
[0019] In a further embodiment, the arcuate groove is formed on the first outer side surface and is close to the outer inclined surface.
[0020] In a further embodiment, when the torque at the kinetic energy output end is within a preset threshold, the arc groove is located within the first guide hole.
[0021] In a further embodiment, the diameter of the small steel ball is less than or equal to the difference in diameter between the first guide hole and the second mounting hole.
[0022] In a further embodiment, an adjusting bolt is mounted on the end of the stacked spring.
[0023] In a further embodiment, the height of the end of the arc groove near the small steel ball is less than or equal to the height of the end of the arc groove away from the small steel ball.
[0024] In a further embodiment, the depth of the arc groove is less than 8% of the diameter of the small steel ball.
[0025] Beneficial effects:
[0026] 1. This utility model can effectively prevent the large steel ball from rubbing against the end face of the ejector housing when the torque is overloaded. The small steel ball slides into the arc groove instantly, causing the ejector rod to shift again. Its end can quickly move away from the end face of the ejector housing again, and at the same time, the ejector rod is self-locked.
[0027] 2. This application has a clever structure that utilizes the existing spring force and the misalignment of the small steel ball and the arc groove, thus achieving high efficiency in mechanical design. Attached Figure Description
[0028] Figure 1 This is a schematic diagram of the overall structure of this utility model.
[0029] Figure 2 This is a schematic diagram of the working state of this utility model.
[0030] Figure 3 This is a partial structural schematic diagram of the present invention.
[0031] Figure 4 This is a schematic diagram of the operation of this utility model under torque overload conditions.
[0032] The labels in the figure are as follows: 1. Ball socket connector; 2. Ejector housing; 3. Ejector rod; 4. Stacked spring; 5. Large steel ball; 6. Small steel ball; 7. Spherical groove; 8. Adjusting bolt; 9. Pressure plate; 10. Assembly area; 21. First guide hole; 22. Second mounting hole; 23. Inner inclined surface; 31. Circular groove; 32. First outer surface; 33. Second outer surface; 34. Outer inclined surface. Detailed Implementation
[0033] The present invention will be further described below with reference to the accompanying drawings.
[0034] Example 1
[0035] Based on the existing self-locking torque limiter solutions mentioned in the background art, this application makes improvements so that the torque limiter can extend its service life, while ensuring that the preset value of the torque remains unchanged after multiple safety torque protection operations, and the limiter can still be used normally.
[0036] The innovation of this embodiment lies in the secondary utilization of traditional elastic force, such as spring force, by using a small steel ball 6 and opening an arc groove 31 at the corresponding position of the push rod 3. When the output torque exceeds the safety setting standard, the push rod 3 begins to move away from the output end. At this instant, the small steel ball 6, with the help of the existing elastic force, begins to enter the arc groove 31 within the preset track or space. At the same time, the small steel ball 6 applies a force that causes the push rod 3 to move backward, causing the push rod 3 to move quickly again. That is, through the small steel ball 6, the push rod 3 is once again provided with a pushing force that can displace a certain distance, so that the large steel ball 5 no longer contacts the end face of the ball socket joint 1.
[0037] To better illustrate this embodiment, a detailed explanation will be provided based on a conventional limiter. Figures 1 to 3 Please provide a more detailed description.
[0038] The specific structure mainly includes: a pin housing 2, a ball joint 1, a push rod 3, a small steel ball 6, and an elastic component that provides elastic force to the small steel ball 6 and the push rod 3, such as... Figure 1 As shown, the assembly scheme and principle are as follows: the ejector housing 2 is assembled at the kinetic energy output end of the motor, etc. A spherical groove 7 is opened on the other end face of the ball joint, the depth of which is less than the radius of the large steel ball 5. The ball joint 1 is assembled at the kinetic energy transmission end, such as on a coupling. An assembly hole is opened inside the ball joint 1 for assembling the ejector rod 3, elastic component, etc. The ejector rod 3 is slidably set in the assembly hole. A large steel ball 5 is installed at the end of the ejector rod 3. The shape of the large ball is adapted to the spherical groove 7. Numerous small steel balls 6 are set at the output end of the elastic component. The elastic component is used to provide a preset elastic force. Through the small steel balls 6, the ejector rod 3 is positioned in a preset position within the inner hole under the action of this elastic force. Figure 1 As shown, when the push rod 3 moves, it needs to overcome the spring force. The outer side of the push rod 3 has an arc groove 31, which is adapted to the shape of the small steel ball 6. When the small steel ball 6 slides into the arc groove 31, the push rod 3 is subjected to the component of the elastic force away from the spherical groove 7. The small steel ball 6 slides into the arc groove 31, forming a self-locking effect on the current displacement of the push rod 3. At this time, the large steel ball 5 can move away from the end face of the ball socket joint 1 and will not rub against the end face of the ejector housing 2.
[0039] To better illustrate the specific details, the ball joint 1 is located away from the ejector housing 2, such as... Figures 1 to 2 As shown, from left to right, the inner diameter of the assembly hole increases in a stepped manner, including at least the first guide hole 21, the second mounting hole 22, and the inner inclined surface 23 generated by the diameter difference between the two inner holes. The inner diameter of the first guide hole 21 is the smallest. Under the action of elastic force, the small steel ball 6 is pressed against the inner inclined surface 23, and the shape of the inner inclined surface 23 is adapted to the small steel ball 6.
[0040] At the same time, push rod 3 along its axial direction, such as Figures 1 to 2As shown, its diameter decreases in a stepped manner, including at least a first outer surface 32 and a second outer surface 33. The first outer surface 32 has the largest diameter, and the two outer surfaces have different diameters, forming an outer inclined surface 34. The first outer surface 32 is adapted to the first guide hole 21, and the second outer surface 33 and the second mounting hole 22 form an assembly area 10 for assembling elastic components. Under the action of elastic force, the small steel ball 6 is pressed against the outer inclined surface 34, and the shape of the outer inclined surface 34 is adapted to the small steel ball 6. Figures 1 to 2 As shown, the inner inclined surface 23 and the outer inclined surface 34 adopt an angled structure to limit the position of the small steel ball 6 under the action of spring force.
[0041] The elastic component in this embodiment includes at least: a stacked spring 4 and a pressure plate 9. The stacked spring 4 is disposed within the assembly area 10 and can be wrapped around the outer circumference of the push rod 3. Alternatively, multiple springs can be selected and disposed on the outer circumference of the push rod 3 respectively. The push rod 3 passes through the pressure plate 9, which is located at the output end of the stacked spring 4. The cross-section of the output end of the pressure plate 9 is an inclined plane, and the direction line of the force applied to the small steel ball 6 passes through one point on the axis of the push rod 3. The direction lines of the force applied to the small steel ball 6 by the end of the pressure plate 9 in contact with the small steel ball 6 all pass through the axis of the push rod 3 and converge at the same point. This results in the force exerted by the small steel ball 6 on the push rod 3 when the spring force is transmitted to the small steel ball 6 not being parallel to the axis of the push rod 3, but rather forming a specified angle with the axis of the push rod 3. Combined with the aforementioned arc groove 31, the effect of this solution can be achieved. The arc groove 31 is formed on the first outer surface 32 and close to the outer inclined surface 34. When the torque at the kinetic energy output end is within a preset threshold, the arc groove 31 is located within the first guide hole 21. When the torque at the kinetic energy output end is overloaded, the arc groove 31 is located within the second mounting hole 22.
[0042] Furthermore, the diameter of the small steel ball 6 is less than or equal to the diameter difference between the first guide hole 21 and the second mounting hole 22. An adjusting bolt 8 is installed at the end of the stacked spring 4 to adjust the set value of the spring force.
[0043] Furthermore, such as Figure 3 As shown, the height of the end of the arc groove 31 near the small steel ball 6 is less than or equal to the height of the end of the arc groove 31 away from the small steel ball 6, which facilitates the sliding of the small steel ball 6. At the same time, the depth of the arc groove 31 is less than 8% of the diameter of the small steel ball 6. This ensures that the small steel ball 6 locks the push rod 3 and cannot move freely, and also ensures that during reset, the small steel ball 6 can easily exit the arc groove 31 and return to the outer inclined surface 34 of the push rod 3.
[0044] Working principle: In the meshing state, the inner inclined surface 23 on the inner side of the ejector housing 2 and the inclined surface of the pressure plate 9, under the spring force of the disc spring 4, press the small steel ball 6 onto the outer inclined surface 34 of the ejector rod 3, causing the large steel ball 5 on the ejector rod 3 to push forward against the spherical groove 7, and the power output end drives the equipment to operate. When the equipment is overloaded, such as... Figure 4 As shown, the overload torque will push the push rod 3 away from the spherical groove 7. At this time, the push rod 3 slides backward with the ejector housing 2 as a reference. The small steel ball 6 will roll upward along the outer inclined surface 34 of the push rod 3 under the spring force of the disc spring 4. When the large steel ball 5 gets out of the spherical groove 7, the small steel ball 6 just enters the edge of the arc groove 31 on the outer side of the push rod 3. Because the pressure plate 9 is always under the elastic force of the disc spring 4, the pressure plate 9 will push these small steel balls 6 into the arc groove 31 in an instant. In this way, these small steel balls 6 will lock the push rod 3, and the push rod 3 cannot move freely. During the rolling process of the small steel ball 6, a force will be generated that push rod 3 moves backward, causing the push rod 3 to move backward quickly again. As a result, a larger gap will be generated between the large steel ball 5 at the end of the push rod 3 and the spherical groove 7. At this time, there is no residual torque between the power output end and the equipment end.
[0045] The above are merely preferred embodiments of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model.
Claims
1. A self-locking pin-type torque limiter, comprising: The ejector housing is assembled to the kinetic energy output end; the ejector housing has assembly holes of different diameters inside; Ball joint, assembled at the equipment end; The ball joint has a spherical groove at its end; A push rod is slidably disposed within the mounting hole; a large steel ball is mounted at the end of the push rod, the shape of which is adapted to the spherical groove. Its characteristic is that it further includes an elastic component disposed in the assembly hole, and a plurality of small steel balls assembled at the output end of the elastic component; The elastic component is used to provide a preset elastic force, so that the push rod is in a preset position inside the inner hole under the action of the elastic force; The outer side of the push rod has an arc groove that matches the shape of the small steel ball. When the small steel ball slides into the arc groove, the push rod is subjected to a component of the elastic force away from the spherical groove, thus forming a self-locking mechanism for the current displacement of the push rod.
2. A self-locking plunger type torque limiter according to claim 1, wherein The inner diameter of the assembly hole increases in a stepped manner along its length, and includes at least a first guide hole, a second mounting hole, and an inner inclined surface between the two inner holes. The inner diameter of the first guide hole is the smallest. Under the action of elastic force, the small steel ball is pressed against the inner inclined surface, and the shape of the inner inclined surface is adapted to the small steel ball.
3. A self-locking plunger type torque limiter according to claim 2, wherein The diameter of the push rod decreases in a stepped manner along its axial direction, and includes at least a first outer side and a second outer side; the diameter of the first outer side is the largest, and an outer inclined surface is formed between the two outer sides; the first outer side is adapted to the first guide hole, and the second outer side and the second mounting hole form an assembly area for assembling the elastic element; the small steel ball is pressed against the outer inclined surface under the action of elastic force, and the shape of the outer inclined surface is adapted to the small steel ball.
4. A self-locking plunger type torque limiter according to claim 3, wherein The resilient component includes at least: A stacked spring is disposed within the assembly area and on the outer circumference of the push rod; A pressure plate is disposed in the assembly area and located at the output end of the stacked spring; the output end face of the pressure plate is an inclined surface, and the direction line of the force applied to the small steel ball passes through one of the points on the axis of the push rod.
5. A self-locking plunger type torque limiter according to claim 3, wherein The arc groove is formed on the first outer side surface and is close to the outer inclined surface.
6. A self-locking plunger type torque limiter according to claim 3, wherein When the torque at the kinetic energy output end is within a preset threshold, the position of the arc groove is located within the first guide hole.
7. A torsion limiter with self-locking ejector pin according to claim 3, characterized in that The diameter of the small steel ball is less than or equal to the difference in diameter between the first guide hole and the second mounting hole.
8. A self-locking pin-type torque limiter according to claim 4, characterized in that, An adjusting bolt is installed at the end of the stacked spring.
9. A self-locking plunger type torque limiter according to claim 3, wherein The height of the end of the arc groove near the small steel ball is less than or equal to the height of the end of the arc groove away from the small steel ball.
10. A self-locking plunger type torque limiter according to claim 3, wherein The depth of the arc groove is less than 8% of the diameter of the small steel ball.