Overrunning clutch and its transmission assembly

Abstract

The scheme discloses a kind of overrunning clutch and its transmission assembly, the overrunning clutch includes coaxially arranged and mutually nested outer ring and inner ring, and outer ring includes annular and coaxially arranged conversion piece and connecting piece.The conversion piece includes mutually parallel and coaxially arranged first annular substrate and second annular substrate, and multiple oblique rods are arranged between two substrates.Multiple oblique rods are same in shape, same in size and same in inclination angle, their first end is connected to the side of first annular substrate towards second annular substrate, and connection point is equidistantly distributed on first circumference, their second end is connected to the side of second annular substrate towards first annular substrate, and connection point is equidistantly distributed on second circumference;First circumference and second circumference are same in diameter, and they are coaxial with first annular substrate, second annular substrate.Second annular substrate is fixedly connected with connecting piece;The outer circumferential surface of inner ring is provided with first taper surface, and the inner circumferential surface of connecting piece is provided with second taper surface matched therewith.

Description

Technical Field

[0001] This solution belongs to the field of mechanical transmission technology, specifically involving an overrunning clutch and its transmission components. Background Technology

[0002] Overrunning clutches are widely used in civilian transportation (bicycles, motorcycles, electric vehicles, etc.), robotics, helicopter drive systems, and many other fields. Typical overrunning clutches include ratchet, roller, and wedge types. However, traditional structures suffer from discontinuous contact at multiple points, leading to failure after a certain degree of wear. Traditional clutches are multi-component assemblies sensitive to manufacturing processes and precision, increasing manufacturing costs and the probability of failure. Summary of the Invention

[0003] This solution aims to overcome at least one defect in the prior art and provide a new overrunning clutch that has a simple structure, is not sensitive to machining accuracy, and can perform good self-compensation after wear.

[0004] To solve the above-mentioned technical problems, the following technical solution is adopted:

[0005] In a first aspect, an overrunning clutch is proposed, comprising an outer ring and an inner ring coaxially arranged and nested within each other. The outer ring includes a conversion element and a connecting element, both annular and coaxially arranged. The conversion element includes a first annular base plate, a second annular base plate, and multiple inclined rods. The first and second annular base plates are parallel to each other and coaxially arranged. The multiple inclined rods are disposed between the first and second annular base plates. The multiple inclined rods have the same shape, size, and inclination angle. Their first ends are connected to the side of the first annular base plate facing the second annular base plate, and their connection points are equidistantly distributed on the first circumference. Their second ends are connected to the side of the second annular base plate facing the first annular base plate, and their connection points are equidistantly distributed on the second circumference. The first and second circumferences have the same diameter, and they are all coaxial with the first and second annular base plates. The second annular base plate is fixedly connected to the end face or outer circumferential surface of the connecting element. The outer circumferential surface of the inner ring is provided with a first conical surface, and the inner circumferential surface of the connecting element is provided with a matching second conical surface.

[0006] In this design, the inner ring and the connecting component together form a conical friction structure. Through the cooperation of this conical friction structure and the conversion component, both drive and overrun modes can be achieved. In the free state, the first and second conical surfaces of the conical friction structure are in slight contact. Under the action of the drive torque, the initial contact force generates an initial torque acting on the second annular base plate of the conversion component. Combined with the pulling action of the inclined rod, this causes the second annular base plate to generate an axial force that presses against the conical friction structure. There is no relative rotation between the first and second conical surfaces, and the torque is transmitted, achieving the drive mode. Under the action of the overrun torque, the initial contact force generates an initial torque acting on the second annular base plate of the conversion component. Combined with the pushing action of the inclined rod, this causes the second annular base plate to generate an axial force in the opposite direction, separating the first and second conical surfaces. The torque is not transmitted, achieving the overrun mode. Compared with traditional overrunning clutches, the clutch structure proposed in this design is simple, insensitive to machining precision, and can perform good self-compensation after wear.

[0007] Specifically, under the action of driving torque, the above-mentioned overrunning clutch satisfies When self-locking occurs, there is no relative rotation between the first and second conical surfaces, and torque is transmitted, achieving the driving mode. Here, μ represents the coefficient of kinetic friction between the first and second conical surfaces, η1 represents the force-to-torque ratio of the conversion element under pure torsion, r represents the equivalent radius at the contact point between the first and second conical surfaces, and θ represents the slope of the first and second conical surfaces. Under overrunning torque, the first and second conical surfaces separate, and torque is not transmitted, achieving the overrunning mode.

[0008] A tapered friction structure with a smaller slope has better self-locking capability, but it is necessary to prevent the tapered friction structure from jamming. Therefore, the above-mentioned overrunning clutch should ideally meet the following requirements: Where μ represents the coefficient of kinetic friction between the first and second conical surfaces, and θ represents the slope of the first and second conical surfaces.

[0009] The ratio η1 of force to torque of the conversion component under pure torsion is related to the diagonal bar structure. The diagonal bar is preferably a strip structure, and more preferably a strip structure in which both the first and second ends are arc-shaped and the center of the arc faces the outer peripheral surface of the conversion component.

[0010] The inner ring can be formed by combining a first half-ring and a second half-ring with identical structures, so as to be mounted on the input shaft for input torque and drive-connected to the input shaft; the first half-ring and the second half-ring can be connected by fasteners to hold the input shaft and achieve the drive connection. The inner ring can also be a complete ring with an inner diameter slightly larger than the outer diameter of the input shaft, and drive-connected to the input shaft by a key connection. Regardless of whether the inner ring is a complete ring or composed of two half-rings, it can be configured to include a hollow cylindrical segment and a hollow frustum segment arranged coaxially, the outer peripheral surface of the hollow frustum segment forming the aforementioned first conical surface, the lower base of the hollow frustum segment facing the first annular base plate and connected to one end of the hollow cylindrical segment.

[0011] Secondly, a transmission assembly is proposed, including an input shaft, an output component, and the aforementioned overrunning clutch. The inner ring of the overrunning clutch is sleeved on the input shaft and is drive-connected to the input shaft. The first annular base plate of the overrunning clutch is drive-connected to the output component.

[0012] This solution employs a specially structured overrunning clutch. Through the cooperation of a conical friction structure and a conversion element, this overrunning clutch can achieve both drive and overrunning modes. Compared to traditional overrunning clutches, this overrunning clutch has a simpler structure, is less sensitive to machining precision, and can perform self-compensation effectively after wear, thus extending the service life of the transmission components.

[0013] Compared with existing technologies, this solution has the following advantages: The overrunning clutch proposed in this solution achieves driving mode and overrunning mode through the cooperation of a special conversion component and a conical friction structure. Compared with traditional overrunning clutches, this overrunning clutch has a simple structure, is not sensitive to machining accuracy, and can perform self-compensation after wear. Attached Figure Description

[0014] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this solution. To better illustrate the solution, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0015] Figure 1 This is a three-dimensional structural diagram of the overrunning clutch and the transmission components it comprises.

[0016] Figure 2 This is a side view of the overrunning clutch and the transmission components it comprises.

[0017] Figure 3 This is a structural schematic diagram of the conversion component.

[0018] Figure 4 This is a structural diagram of the connector.

[0019] Figure 5 This is a schematic diagram of the inner ring structure.

[0020] Figure 6 This is a schematic diagram of the force analysis of the working state of the conical friction structure.

[0021] Figure 7 This is a schematic diagram of the force analysis of the conical friction structure in the transcendent state.

[0022] Figure 8 This is a schematic diagram of the force analysis of a conical friction structure in a static state.

[0023] Explanation of reference numerals in the attached drawings: outer ring 100, conversion component 110, first annular base plate 111, second annular base plate 112, inclined rod 113, connector 120, second conical surface 121, inner ring 200, hollow cylindrical segment 210, hollow frustum segment 220, first conical surface 221, input shaft 310. Detailed Implementation

[0024] To enable those skilled in the art to better understand this solution, the following detailed description is provided in conjunction with specific embodiments.

[0025] Figures 1-2 An embodiment of an overrunning clutch and its associated transmission assembly is shown. The transmission assembly includes an input shaft 310, an output component (not shown), and an overrunning clutch; the overrunning clutch includes an outer ring 100 and an inner ring 200 that are coaxially arranged and nested together, the outer ring 100 including a transition component 110 and a connecting component 120, both of which are annular and coaxially arranged.

[0026] The conversion component 110 can achieve the conversion between compression and torsion or tension and torsion through elastic deformation. Its structure includes a first annular base plate 111, a second annular base plate 112, and multiple (three or more) diagonal bars 113, such as... Figure 3 As shown. The first annular substrate 111 and the second annular substrate 112 are parallel to each other and coaxially arranged, and multiple diagonal rods 113 are disposed between the first annular substrate 111 and the second annular substrate 112. The first annular substrate 111 and the second annular substrate 112 are collectively referred to as substrates, which can be configured as circular rings or regular polygonal rings. The number of sides of the regular polygonal ring is preferably an integer multiple of the number of diagonal rods 113. All diagonal rods 113 have the same shape, the same size, and the same inclination angle, where the inclination angle refers to the angle between the diagonal rod 113 and the plane of the substrate.

[0027] The first ends of all the diagonal rods 113 are connected to the side of the first annular substrate 111 facing the second annular substrate 112, and the connection points are equidistantly distributed on the first circumference. Their second ends are connected to the side of the second annular substrate 112 facing the first annular substrate 111, and the connection points are equidistantly distributed on the second circumference. The connection points can be understood as the geometric centers of the end faces of the diagonal rods 113. The first circumference and the second circumference can be collectively referred to as the circumference enclosed by the diagonal rods 113. They have the same diameter and are both coaxial with the first annular substrate 111 and the second annular substrate 112. That is, the first annular substrate 111, the second annular substrate 112, the first circumference, and the second circumference are all coaxial.

[0028] The second annular substrate 112 is fixedly connected to the end face of the connector 120, such as Figure 1 As shown, specifically, the side of the second annular substrate 112 facing away from the first annular substrate 111 is fixedly connected to one end face of the connector 120. Furthermore, the second annular substrate 112 can also be fixedly connected to the outer peripheral surface of the connector 120, specifically, the inner peripheral surface of the second annular substrate 112 is fixedly connected to the outer peripheral surface of the connector 120. It should be noted that the second annular substrate 112 and the connector 120 can also be integrated into one piece.

[0029] The outer circumferential surface of the inner ring 200 is provided with a first conical surface 221, such as Figure 5 As shown, the inner circumferential surface of the connector 120 is provided with a second conical surface 121 that mates with it, such as... Figure 4 As shown, the two constitute a conical friction structure, with the first conical surface 221 and the second conical surface 121 of the conical friction structure slightly in contact in the free state. The inner ring 200 is sleeved on the input shaft 310 and is drivenly connected to the input shaft 310. The first annular base plate 111 is drivenly connected to the output component. The axial displacement of the input shaft 310 and the output component is constrained, which also constrains the axial displacement of the inner ring 200 and the first annular base plate 111.

[0030] Under the action of the torque in the driving direction (hereinafter referred to as driving torque), the initial contact force generates an initial torque acting on the second annular base plate 112 of the conversion element 110. Combined with the pulling action of the inclined rod 113, this causes the second annular base plate 112 to generate an axial force that presses against the conical friction structure. There is no relative rotation between the first conical surface 221 and the second conical surface 121, and the torque is transmitted, thus achieving the driving mode. Under the action of the torque in the overtaking direction (hereinafter referred to as overtaking torque), the initial contact force generates an initial torque acting on the second annular base plate 112 of the conversion element 110. Combined with the pushing action of the inclined rod 113, this causes the second annular base plate 112 to generate an axial force in the opposite direction, causing the first conical surface 221 and the second conical surface 121 to separate. The torque is not transmitted, thus achieving the overtaking mode. In short, this overtaking clutch can achieve both driving and overtaking modes through the cooperation of the conical friction structure and the conversion element 110. It should be noted that the overtaking direction is the opposite direction of the driving direction. Figure 1 The input direction shown is the driving direction.

[0031] The self-locking problem of this overrunning clutch under driving load can be analyzed using micro-elements on the contact surface between the inner ring 200 and the connecting member 120, such as... Figure 6 The formula for calculating the total torque T is:

[0032] T=∫rdF T (1)

[0033] Where r represents the equivalent radius at the contact point between the first and second conical surfaces. Under the load of torque T, the conversion component 110 has no axial strain in the x-direction, and the axial force F... D This is caused by the pressure-torsion behavior of the conversion element 110:

[0034] F D =η1T (2)

[0035] Where η1 represents the ratio of force to torque of the conversion element 110 under pure torsion. For simplified calculation, it is assumed that r is a constant and exists:

[0036] dF D =η1rdF T (3)

[0037] In the xy plane, force dF N dF D and dF R In equilibrium:

[0038]

[0039] Where θ represents the slope of the first conical surface 221 and the second conical surface 121, the frictional force is calculated from this:

[0040]

[0041] Assume the maximum static friction coefficient equals the kinetic friction coefficient. If the maximum static friction force is greater than the shear force, then:

[0042]

[0043]

[0044] When inequality (7) is satisfied, the overrunning clutch self-locks; otherwise, it overruns.

[0045] like Figure 7 As shown, under the action of reverse torque T, the force dF D The reversal also occurs, with the first conical surface 221 and the second conical surface 121 separating, thus achieving transcendence.

[0046] A tapered friction structure with a smaller slope has better self-locking capability, but it is necessary to prevent the tapered friction structure from jamming. For example... Figure 8 As shown, after driving, the deformation of the conical friction structure will generate a radial force dF on the contact surface. R Compression force dF N This leads to frictional force dF S The maximum static friction force can be expressed as:

[0047]

[0048] If the maximum static friction force is greater than dF R The component parallel to the contact surface may cause the structure to jam. To prevent jamming, it is best to satisfy:

[0049]

[0050]

[0051] The force-to-torque ratio η1 of the conversion element 110 under pure torsion is related to the structure of the diagonal member 113. For example... Figure 3 As shown, the inclined rod 113 is designed as a strip structure, with both its first and second ends being arc-shaped and the center of the arc facing the outer circumference of the conversion member 110. This is beneficial to improving the force-to-torque ratio η1 of the conversion member 110 under pure torsional conditions, so that the overrunning clutch can achieve the driving mode under greater driving torque.

[0052] like Figure 5As shown, the inner ring 200 is formed by combining a first half-ring and a second half-ring with identical structures, so as to be mounted on the input shaft 310 for input torque and to be driven by the input shaft 310; the first half-ring and the second half-ring are connected by fasteners, thereby holding the input shaft 310 tightly to achieve the drive connection. Alternatively, the inner ring 200 can also be a complete ring with an inner diameter slightly larger than the outer diameter of the input shaft 310, and is driven by a key connection with the input shaft 310. Regardless of whether the inner ring 200 is a complete ring or is formed by combining two half-rings, it can be configured to include a hollow cylindrical section 210 and a hollow frustum section 220 arranged coaxially, the outer peripheral surface of the hollow frustum section 220 forming the aforementioned first conical surface 221, and the lower base of the hollow frustum section 220 facing the first annular base plate 111 and connected to one end of the hollow cylindrical section 210.

[0053] Compared with traditional overrunning clutches, this overrunning clutch has a simple structure, is not sensitive to machining precision, can perform self-compensation after wear, and the transmission components composed of it have stable performance and long service life.

[0054] Obviously, the above embodiments of this solution are merely examples for clearly illustrating this solution, and are not intended to limit the implementation of this solution. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this solution should be included within the scope of protection of the claims of this solution.

Claims

1. An overrunning clutch, comprising an outer ring and an inner ring coaxially arranged and nested within each other, characterized in that, The outer ring includes a conversion component and a connector, both of which are annular and coaxially arranged. The conversion component includes a first annular base plate, a second annular base plate, and multiple inclined rods. The first annular base plate and the second annular base plate are parallel to each other and coaxially arranged. The multiple inclined rods are arranged between the first annular base plate and the second annular base plate. The multiple inclined rods have the same shape, size, and inclination angle. Their first ends are connected to the side of the first annular base plate facing the second annular base plate, and their connection points are equidistantly distributed on the first circumference. Their second ends are connected to the side of the second annular base plate facing the first annular base plate, and their connection points are equidistantly distributed on the second circumference. The first circumference and the second circumference have the same diameter and are both coaxial with the first annular base plate and the second annular base plate. The second annular base plate is fixedly connected to the end face or outer circumferential surface of the connector. The outer circumferential surface of the inner ring is provided with a first conical surface, and the inner circumferential surface of the connector is provided with a second conical surface that mates with it.

2. The overrunning clutch according to claim 1, characterized in that, The overrunning clutch satisfies: Where μ represents the coefficient of kinetic friction between the first and second conical surfaces, and θ represents the slope of the first and second conical surfaces.

3. The overrunning clutch according to claim 1, characterized in that, Under the action of driving torque, the overrunning clutch satisfies Self-locking; where μ represents the coefficient of dynamic friction between the first and second conical surfaces, η1 represents the ratio of force to torque of the conversion component under pure torsion, r represents the equivalent radius of the contact position between the first and second conical surfaces, and θ represents the slope of the first and second conical surfaces.

4. The overrunning clutch according to claim 1, characterized in that, Under the action of overrunning torque, the overrunning clutch overruns.

5. The overrunning clutch according to any one of claims 1 to 4, characterized in that, The diagonal bar is designed as a strip structure.

6. The overrunning clutch according to claim 5, characterized in that, Both the first and second ends of the diagonal rod are arc-shaped with the center of the arc facing the outer circumference of the conversion component.

7. The overrunning clutch according to any one of claims 1 to 4, characterized in that, The inner ring is formed by combining a first half-ring and a second half-ring with the same structure.

8. The overrunning clutch according to claim 7, characterized in that, The first half-ring and the second half-ring are connected by fasteners.

9. The overrunning clutch according to claim 7, characterized in that, The inner ring includes a hollow cylindrical segment and a hollow frustum segment arranged coaxially; the outer peripheral surface of the hollow frustum segment forms the first conical surface, with its lower base facing the first annular substrate and connected to one end of the hollow cylindrical segment.

10. A transmission assembly, characterized in that, It includes an input shaft, an output component, and an overrunning clutch as described in any one of claims 1 to 9, wherein the inner ring of the overrunning clutch is fitted onto the input shaft and is drive-connected to the input shaft, and the first annular base plate of the overrunning clutch is drive-connected to the output component.

Images