Wave spring and novel overrun clutch

Abstract

The invention relates to a wave spring and a novel overrun clutch. The wave spring comprises a lintel, a special-shaped roller fixing window hole, a cross beam, a concave arc, an arc transition rectangular hole, a reverse bending part, a pre-tightening elastic sheet and a lintel bending part, a concave arc is arranged on the lintel; an arc transition rectangular hole is formed in the cross beam, a pre-tightening elastic sheet is arranged on one side of the arc transition rectangular hole, the end part of the pre-tightening elastic sheet is in an arc shape in good contact with the special-shaped roller, and a reverse bending part for keeping elastic clamping is arranged in the middle of the pre-tightening elastic sheet; the left lintel and the right lintel are provided with lintel bending parts which correspond to the reverse bending parts in position and are opposite in direction, and the lintel bending parts are matched with the reverse bending parts to jointly keep the elasticity of the wave spring. The wave spring is ingenious in design and simple in structure, the rigidity of the wave spring is evenly distributed, the pre-tightening elastic piece makes good contact with the special-shaped roller, elasticity attenuation is effectively reduced, the performance of the clutch is greatly improved, and the wave spring has good market prospects and development space compared with the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of clutches, and in particular to a wave spring and a novel overrunning clutch. Background Art

[0002] The overrunning clutch is installed between the inner raceway of the inner shaft and the outer raceway of the outer ring. It is generally composed of an inner cage, an outer cage, a special-shaped roller and a wave spring. Figure 1 As shown. The essence of the working principle of this overrunning clutch is self-locking: it can form a locking state by relying on friction without relying on external pressure. The special-shaped roller is the main load-bearing part; the inner and outer retainers leave a certain gap with the inner and outer rings of the clutch respectively to achieve the guiding function, and the multiple windows of the retainer allow the special-shaped rollers to be evenly distributed, thereby maximizing the load of the clutch; the main function of the wave spring is to keep the special-shaped roller in contact with the inner and outer rings of the clutch at all times through the pre-tightening elastic sheet of the window hole, ensuring that the clutch can transition from the overrunning state to the wedging state at any time.

[0003] The working modes of the overrunning clutch are divided into two types: wedging and overrunning. The wedging mode is the working mode in which the clutch transmits torque; the overrunning mode is the working mode in which the speed between the input end (connected to the engine) and the output end (connected to the transmission system) is different, and the clutch does not transmit torque.

[0004] The working principle of overrunning clutch is as follows Figure 2 As shown, the working surfaces of the special-shaped roller are mainly the upper and lower eccentric arc surfaces. The dimension b on the special-shaped roller is larger than the distance a between the inner and outer rings of the clutch, while the dimension c on the special-shaped roller is smaller than the distance a between the inner and outer rings of the clutch.

[0005] When the inner ring of the clutch rotates counterclockwise, the special-shaped roller is subjected to the elastic force of the wave spring preload elastic sheet and the friction between the special-shaped roller and the inner and outer rings of the clutch, causing the special-shaped roller to wedge between the inner and outer rings of the clutch, thereby completing the movement and torque transmission between the two shaft systems, and the clutch is in a wedged state; when the inner ring of the clutch rotates clockwise, the special-shaped roller is also subjected to the elastic force of the wave spring preload elastic sheet and the friction between the special-shaped roller and the inner and outer rings of the clutch, causing the inner and outer rings of the clutch and the special-shaped roller to move independently of each other, and the clutch is in an overrunning state.

[0006] The main function of the wave spring is to provide preload to the profiled roller through the elastic sheet structure in the middle, so that the profiled roller always keeps in contact with the inner raceway of the inner shaft and the outer raceway of the outer ring. Figure 3As shown. This type of wave spring can meet the working requirements under normal circumstances, but under the requirements of high speed and long life, there are the following problems: (1) After the wave spring is installed in the inner and outer retainers, it is bent from a strip shape to a ring shape that is close to the inner wall of the outer retainer. During the bending process, due to its porous special-shaped structure, it becomes an irregular ring shape. The force of the elastic sheet at the window hole position on the special-shaped roller is uneven, making the clutch wedging process unstable and affecting the performance of the clutch. (2) The wave spring is a stamping part with poor roughness. The contact position between the end of the single preload elastic sheet at the window hole position and the side of the special-shaped roller is affected by the processing method, resulting in greater friction and uneven contact with the special-shaped roller, which interferes with the posture of the special-shaped roller, causing abnormal wear and affecting the performance of the clutch. (3) The preload elastic sheet at the window hole position of the wave spring shows fatigue extension at the bend after the clutch is used many times, and its elastic force is attenuated to varying degrees, affecting the performance of the clutch.

[0007] How to design a wave spring and a new overrunning clutch with ingenious design, simple structure, uniform distribution of wave spring stiffness, good contact between the preloaded elastic sheet and the special-shaped roller, effective reduction of elastic force attenuation, and greatly improved clutch performance is a problem that needs to be solved at present. Summary of the invention

[0008] In order to solve the problems of uneven elastic force distribution, uneven friction and contact, elastic force attenuation, and clutch performance impact in the existing overrunning clutch wave spring, the present invention provides a wave spring and a novel overrunning clutch to achieve ingenious design, simple structure, uniform stiffness distribution of the wave spring, good contact between the pre-tightening elastic sheet and the special-shaped roller, effectively reducing elastic force attenuation, and greatly improving clutch performance.

[0009] The technical solution adopted by the present invention to solve the above technical problems is: a wave spring, which is a circular array structure, including left and right two beams, a special-shaped roller fixing window hole, a crossbeam, a concave arc, an arc transition rectangular hole, a reverse bending portion, a pre-tightening elastic sheet and a beam bending portion, a plurality of crossbeams perpendicular to each other are arranged between the left and right beams, and a special-shaped roller fixing window hole is formed between two adjacent crossbeams; the beam is provided with a concave arc for easy bending into a circular ring; the crossbeam is provided with an arc transition rectangular hole for easy maintenance of the ring structure, a pre-tightening elastic sheet is arranged on one side of the arc transition rectangular hole, the end of the pre-tightening elastic sheet is arranged in a circular arc shape for good contact with the special-shaped roller, and the middle of the pre-tightening elastic sheet is provided with a reverse bending portion for maintaining elastic clamping; the left and right beams are provided with beam bending portions corresponding to the position of the reverse bending portion and opposite to the direction of the reverse bending portion, so as to cooperate with the reverse bending portion to jointly maintain the elasticity of the wave spring.

[0010] As a further optimization solution of the above-mentioned wave spring, the arc-shaped end of the preload elastic sheet is in smooth contact with the arc surface of the waist of the special-shaped roller.

[0011] A novel overrunning clutch further comprises an outer ring, special-shaped rollers, an outer retaining frame, an inner retaining frame and an inner ring.

[0012] As a further optimization solution of the above-mentioned novel overrunning clutch, the wave spring is arranged between the outer retaining frame and the inner retaining frame, and the special-shaped rollers are arranged in turn in the special-shaped roller fixing window holes of the wave spring.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. The first innovation of the present invention is that the side of the wave spring at the beam position is designed as a concave arc, and the cross beam position is designed as a hollow arc transition rectangular hole, so that the stiffness of the wave spring is evenly distributed, and the bending shape of the wave spring after being installed in the inner and outer retaining frames is closer to a circle.

[0014] 2. The second innovative point of the present invention is that the contact position between the preload elastic sheet at the window hole and the special-shaped roller is designed as a circular arc surface, which ensures good contact between the preload elastic sheet and the special-shaped roller.

[0015] 3. The third innovation of the present invention is that the bending position of the preload elastic sheet at the wave spring window hole is designed to be reversely bent, and the preload elastic sheet is in a compressed state when in use, which can effectively reduce the attenuation of the elastic force, thereby improving the performance of the clutch. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the cross-sectional structure of an existing double-cage type overrunning clutch; Figure 2 It is a partially enlarged schematic diagram of an existing double-cage type overrunning clutch; Figure 3 It is a schematic diagram of the working principle of the overrunning clutch; Figure 4 It is a schematic diagram of the two-dimensional unfolded structure of the wave spring before the structural improvement; Figure 5 It is a schematic diagram of the three-dimensional assembly structure of the wave spring before the structural improvement; Figure 6 This is a schematic diagram of the local structure of the wave spring window hole before the structural improvement; Figure 7 This is a schematic diagram of the contact position between the wave spring and the special-shaped roller before the structural improvement; Figure 8 It is a schematic diagram of the cross-sectional structure of the overrunning clutch after structural improvement; Fig. 9 It is a partial enlarged schematic diagram of the overrunning clutch after structural improvement; Fig.10 It is a schematic diagram of the three-dimensional assembly structure of the wave spring after the structure improvement; Fig.11 This is a partial enlarged schematic diagram of the window hole of the wave spring after the structure is improved; Fig.12 It is a partial enlarged schematic diagram of the wave spring preload elastic sheet after the structure improvement; Fig.13 This is a schematic diagram of the contact position between the new wave spring and the special-shaped roller.

[0017] Markings in the figure: 1 is the outer ring; 2 is the special-shaped roller; 3 is the outer retainer; 4 is the wave spring; 401 is the lintel; 402 is the fixing window hole for the special-shaped roller; 403 is the crossbeam; 404 is the inner concave arc; 405 is the arc transition rectangular hole; 406 is the reverse bending part; 407 is the preloaded elastic sheet; 408 is the lintel bending part; 409 is the same direction bending part; 5 is the inner retainer; 6 is the inner ring. DETAILED DESCRIPTION

[0018] The specific implementation modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0019] like Figure 1 As shown, Figure 1 It is a schematic diagram of the cross-sectional structure of an existing double cage type overrunning clutch. Figure 2 It is a partially enlarged schematic diagram of an existing double-cage type overrunning clutch; the overrunning clutch is installed between the inner raceway of the inner shaft and the outer raceway of the outer ring, and is generally composed of an inner cage 5, an outer cage 3, a special-shaped roller 2 and a wave spring 4.

[0020] like Figure 3 As shown, Figure 3 It is a schematic diagram of the working principle of the overrunning clutch; the working surface of the special-shaped roller 2 is mainly the upper and lower eccentric arc surfaces, the dimension b on the special-shaped roller 2 is larger than the distance a between the inner and outer rings of the clutch, and the dimension c on the special-shaped roller 2 is smaller than the distance a between the inner and outer rings of the clutch.

[0021] When the clutch inner ring 6 rotates counterclockwise, the special-shaped roller 2 is subjected to the elastic force of the preloaded elastic sheet 407 of the wave spring 4 and the friction force between the special-shaped roller 2 and the inner and outer rings of the clutch, so that the special-shaped roller 2 is wedged between the inner and outer rings of the clutch, thereby completing the movement and torque transmission between the two shaft systems, and the clutch is in a wedged state; when the clutch inner ring 6 rotates clockwise, the special-shaped roller 2 is also subjected to the elastic force of the preloaded elastic sheet 407 of the wave spring 4 and the friction force between the special-shaped roller 2 and the inner and outer rings of the clutch, so that the inner and outer rings of the clutch and the special-shaped roller move independently of each other, and the clutch is in an overrunning state.

[0022] like Figure 4 ,5 , 6, and 7, Figure 4 It is a schematic diagram of the two-dimensional unfolded structure of the wave spring before the structural improvement; Figure 5 It is a schematic diagram of the three-dimensional assembly structure of the wave spring before the structural improvement; Figure 6 This is a schematic diagram of the local structure of the wave spring window hole before the structural improvement; Figure 7 This is a schematic diagram of the contact position between the wave spring 4 and the profiled roller 2 before the structural improvement; this type of wave spring 4 can meet the working requirements under normal circumstances, but under the requirements of high speed and long life, there are the following problems: (1) After the wave spring 4 is installed in the inner and outer retainers, it is bent from a band shape to a ring shape that is close to the inner wall of the outer retainer. During the bending process, due to its porous profiled structure, it becomes an irregular ring shape. The force exerted by the elastic sheet at the window position on the profiled roller 2 is uneven, making the clutch wedging process unstable and affecting the performance of the clutch. (2) The wave spring is a stamped part with poor roughness. The contact position between the end of the single preloaded elastic sheet at the window position and the side of the profiled roller 2 is affected by the processing method, resulting in greater friction and uneven contact with the profiled roller 2, which interferes with the posture of the profiled roller 2, causing abnormal wear and affecting the performance of the clutch. (3) The same-direction bending portion 409 on the preload elastic sheet 407 and the lintel bending portion 408 on the lintel 401 have the same bending direction. The end of the preload elastic sheet 407 at the window hole of the wave spring is a flat structure. After the clutch is used many times, fatigue extension occurs at the above-mentioned bending portion, and its elastic force attenuates to varying degrees, affecting the performance of the clutch.

[0023] like Figure 8 , 9 , 10, 11, 12, Figure 8 It is a schematic diagram of the cross-sectional structure of the overrunning clutch after structural improvement; Fig. 9 It is a partial enlarged schematic diagram of the overrunning clutch after structural improvement; Fig.10 It is a schematic diagram of the three-dimensional assembly structure of the wave spring after the structure improvement; Fig.11 This is a partial enlarged schematic diagram of the window hole of the wave spring after the structure is improved; Fig.12It is a partially enlarged schematic diagram of the wave spring preload elastic sheet after the structure is improved; a new type of overrunning clutch, the overrunning clutch also includes an outer ring 1, a special-shaped roller 2, an outer retainer 3, an inner retainer 5 and an inner ring 6. The wave spring 4 is arranged between the outer retainer 3 and the inner retainer 5, and the special-shaped roller 2 is arranged in the special-shaped roller fixing window hole 402 of the wave spring 4 in sequence. The wave spring 4 is a circular array structure, including left and right crossbeams 401, special-shaped roller fixing window holes 402, crossbeams 403, concave arcs 404, arc transition rectangular holes 405, reverse bending portions 406, preloaded elastic sheets 407 and crossbeam bending portions 408. A plurality of crossbeams 403 perpendicular to each other are arranged between the left and right crossbeams 401, and special-shaped roller fixing window holes 402 are formed between two adjacent crossbeams 403; the crossbeams 401 are provided with concave arcs 404 for easy bending into a circular ring; the crossbeams 403 are provided with arc transition rectangular holes 405 for easy maintenance of the ring structure. This structural design makes the bending shape of the wave spring 4 closer to a circle after being installed in the outer retaining frame, so that the wave spring stiffness in the linear direction is evenly distributed, thereby improving the consistency of the action of the wave spring on the special-shaped roller.

[0024] A preload elastic sheet 407 is provided on one side of the arc transition rectangular hole 405, and the end of the preload elastic sheet 407 is set to an arc shape for good contact with the special-shaped roller 2, and a reverse bending portion 406 for maintaining elastic clamping is provided in the middle of the preload elastic sheet 407; and a beam bending portion 408 corresponding to the position of the reverse bending portion 406 and opposite in direction is provided on the left and right beams 401 to cooperate with the reverse bending portion 406 to jointly maintain the elasticity of the wave spring 4.

[0025] The bending position on the preload elastic sheet 407 is designed as a reverse bending portion 406. The wave spring 4 is first installed into the retaining frame, and then the special-shaped roller 2 is installed into the special-shaped roller fixing window hole 402. At this time, the arc at the end of the wave spring preload elastic sheet 407 contacts the side of the waist of the special-shaped roller 2, and deformation occurs at the bending portion. The deformation is a compression deformation, which can effectively reduce the attenuation of the elastic force, thereby improving the performance and service life of the clutch.

[0026] like Fig.13 As shown, Fig.13 It is a schematic diagram of the contact position between the new wave spring and the special-shaped roller. A preload elastic sheet 407 is provided on one side of the arc transition rectangular hole 405. The end of the preload elastic sheet 407 is arranged in an arc shape for good contact with the special-shaped roller 2, so that the arc surface of the end of the preload elastic sheet 407 is in uniform contact with the contact position of the special-shaped roller 2, and the arc surface of the preload elastic sheet 407 is in good contact with the special-shaped roller 2, thereby improving the consistency of the action of the wave spring on the special-shaped roller.

[0027] The present invention has a clever design and a simple structure. The stiffness of the wave spring is evenly distributed, and the pre-tightening elastic sheet has good contact with the special-shaped roller, which effectively reduces the attenuation of the elastic force. The clutch performance is greatly improved, and the problems of uneven elastic force distribution, friction and uneven contact, elastic force attenuation, and clutch performance in the existing overrunning clutch wave spring are solved. Compared with the existing technology, it has a good market prospect and development space.

[0028] The preferred specific implementation modes and embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes and embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the concept of the present invention.

Claims

1. A wave spring, characterized in that: The wave spring (4) is a circular array structure, comprising left and right lintels (401), a special-shaped roller fixing window hole (402), a crossbeam (403), an inwardly concave arc (404), an arc transition rectangular hole (405), a reverse bending portion (406), a preloaded elastic sheet (407) and a lintel bending portion (408); a plurality of crossbeams (403) perpendicular to each other are arranged between the left and right lintels (401); a special-shaped roller fixing window hole (402) is formed between two adjacent crossbeams (403); and a concave arc (404) is arranged on the lintel (401) to facilitate bending into a circular ring. The cross beam (403) is provided with an arc transition rectangular hole (405) for maintaining the annular structure, a preload elastic sheet (407) is provided on one side of the arc transition rectangular hole (405), the end of the preload elastic sheet (407) is provided in an arc shape for good contact with the special-shaped roller (2), and a reverse bending portion (406) for maintaining elastic clamping is provided in the middle of the preload elastic sheet (407); the left and right lintels (401) are provided with lintel bending portions (408) corresponding to the reverse bending portion (406) in position and opposite in direction, so as to cooperate with the reverse bending portion (406) to jointly maintain the elasticity of the wave spring (4).

2. A wave spring according to claim 1, characterized in that: The arc-shaped end of the pre-tightening elastic sheet (407) is in smooth contact with the arc surface of the waist of the special-shaped roller (2).

3. A novel overrunning clutch having the wave spring according to claim 1, characterized in that: The overrunning clutch further comprises an outer ring (1), special-shaped rollers (2), an outer retaining frame (3), an inner retaining frame (5) and an inner ring (6).

4. A novel overrunning clutch as claimed in claim 3, characterized in that: The wave spring (4) is arranged between the outer retainer (3) and the inner retainer (5), and the special-shaped rollers (2) are arranged in sequence in the special-shaped roller fixing window holes (402) of the wave spring (4).

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