Double-groove roller clutch

Abstract

A double-groove roller clutch includes a driven shaft and a mounting base rotatably sleeved on the driven shaft. The mounting base includes a sleeve and a clutch disc fixed to one end of the sleeve. The clutch disc has alternating first and second inclined grooves. A friction plate assembly is sleeved on the sleeve, and a housing is fixed to the driven shaft. A first roller is located in the first inclined groove, and a second roller with a weight less than the first roller is located in the second inclined groove. When the two rollers are at the bottom of the groove, their axial distance from the friction plate assembly is similar. Upon startup, the lighter second roller responds first to the centrifugal force, pushing against the friction plate assembly and providing preload. This makes it easier for the first roller to engage as the speed increases, thus accelerating the clutch response speed. This invention achieves sequential actuation through weight grading, resulting in smooth engagement and rapid response.

Description

Technical Field

[0001] This utility model relates to the field of clutch technology, specifically to a double-groove roller clutch. Background Technology

[0002] The clutch is a key component in a motorcycle's transmission system, used to transmit or disconnect power between the engine and the gearbox. Currently, centrifugal dry clutches are mainly divided into two types: shoe-type and plate-type.

[0003] Shoe-type clutches, such as traditional scooter clutches, transmit torque through centrifugal shoes that directly rub against the inner wall of the clutch housing. However, this structure is prone to vehicle vibration and noise during engagement, and has limited torque capacity, resulting in poor riding comfort.

[0004] To address the aforementioned problems, plate clutches have been widely adopted. One existing dry plate clutch (publication number CN115807820A) includes upper and lower spring fixing plates connected by connecting springs, with a driven plate installed between them. Centrifugal force generated by a centrifugal rotor presses down on the spring fixing plates, causing the driven plate to press against the friction plate to transmit torque. While this structure is more stable than a shoe-type clutch, its centrifugal drive mechanism and pressing mechanism are relatively separated, resulting in a longer axial dimension and a less compact structure.

[0005] Another existing technology (publication number CN112429143B) is a continuously variable transmission (CVT) mechanism for motorcycles. It utilizes a guide post within an inclined hole on the drive wheel, which, under centrifugal force, is thrown out and pushes against a tray, thereby changing the working radius of the transmission belt. This structure reveals the principle of converting centrifugal force into axial thrust using an inclined channel. However, its application is in a transmission mechanism, the drive element is a guide post, the movement is sliding, resulting in relatively high frictional resistance, and there is still room for improvement in response sensitivity.

[0006] Another example is the magnetic automatic clutch (announcement number CN219840944U), which utilizes a flyblock that rolls and moves axially within an inclined guide groove to press against alternately arranged clutch plates. This mechanism uses a rolling method to reduce frictional resistance, but it relies on magnetic attraction to control the engagement timing, resulting in a complex structure and lacking multi-stage actuation to optimize the engagement process.

[0007] A common problem in existing technologies is that the clutch's transition from disengagement to full engagement is abrupt and lacks a smooth transition. During vehicle start-up, the centrifugal components need to overcome spring resistance and eliminate friction plate gaps before establishing effective engagement, resulting in a delayed response that affects start-up smoothness and driving experience.

[0008] Therefore, there is a lack of centrifugal clutches in the prior art that can achieve graded actuation, smooth engagement, and rapid response. Utility Model Content

[0009] The present invention aims to provide a double-groove roller clutch to solve the technical problems of abrupt engagement and delayed response in existing clutches.

[0010] The technical solution adopted by this utility model to solve its technical problem is: a double-groove roller clutch, comprising: a driven shaft; a mounting base rotatably sleeved on the driven shaft for receiving external rotational power; the mounting base includes a sleeve and a clutch disc fixedly disposed at one end of the sleeve; the clutch disc has a plurality of first inclined grooves around its axis, and a second inclined groove is provided between two adjacent first inclined grooves; a friction plate assembly sleeved on the sleeve; a housing fixedly sleeved on the driven shaft; a plurality of first rollers, each correspondingly rolling in each of the first inclined grooves; a plurality of second rollers, each correspondingly rolling in each of the second inclined grooves, wherein the weight of the second rollers is less than the weight of the first rollers, and when the first rollers and the second rollers are at the bottom of their respective grooves, the axial distance between their upper ends and the friction plate assembly is similar.

[0011] Preferably, the friction plate assembly includes at least one first friction plate and at least one second friction plate alternately stacked, wherein the first friction plate is engaged with the sleeve in a manner that allows axial sliding and circumferential linkage, and the second friction plate is engaged with the housing in a manner that allows axial sliding and circumferential linkage.

[0012] Preferably, the outer wall of the sleeve is provided with a plurality of first slots extending along its axial direction, the inner hole of the first friction plate is provided with a first locking block that slides and engages with the first slot; the outer ring of the second friction plate is provided with a second locking block, and the side wall of the sleeve is provided with a plurality of second slots extending along its axial direction, and the second locking block of each second friction plate is correspondingly slidably engaged in each of the second slots.

[0013] Preferably, the first inclined groove is correspondingly provided and connected to the first slot extending axially on the outer wall of the sleeve.

[0014] Preferably, the mounting base further includes a pressure plate, which is fixedly disposed at the other end of the sleeve away from the clutch disc, and the friction plate assembly is located between the clutch disc and the pressure plate.

[0015] Preferably, the mounting base further includes a bushing, the sleeve is connected to the bushing via the pressure plate, the bushing is rotatably fitted onto the driven shaft, and the bushing is used to receive external rotational power and transmit the power to the sleeve.

[0016] Preferably, the first roller and the second roller are cylinders or spheres.

[0017] The beneficial effects of this utility model are: 1. When the vehicle starts and the mounting seat rotates to generate centrifugal force, the lighter second roller only needs a small centrifugal force to roll outward along the second inclined groove first, pushing the friction plate assembly and giving the friction plate assembly a preload, eliminating the gap between each friction plate. When the vehicle starts, the engine speed increases, and the centrifugal force increases, the first roller, because the friction plate assembly has been preloaded, only needs to overcome a small additional resistance to push out and press each friction plate, so that the entire clutch can quickly complete the engagement, significantly increasing the clutch engagement speed. 2. Through the successive action of the two-stage rollers, the clutch engagement process changes from sudden pressing to a gradual process of "pre-pressing-pressing", avoiding the shock and jerking caused by the one-time pressing of the traditional centrifugal clutch, making the power transmission smoother and improving the driving comfort. 3. The centrifugal drive mechanism (tilting groove and roller) is directly integrated on the clutch disc of the mounting base, realizing the integrated design of the drive mechanism and the actuator. There is no need for additional raceway seats, fly block frames and other structures, which shortens the axial dimension, shortens the force transmission path, and makes the power transmission direct and efficient. 4. By using rollers rolling in the inclined groove, centrifugal force is converted into axial thrust. Compared with the sliding of guide pillars, this method results in less frictional resistance, less wear, and extended service life of parts. Attached Figure Description

[0018] Figure 1 This is a usage state diagram of an embodiment of this utility model; Figure 2 This is an exploded view of an embodiment of the present utility model; Figure 3 This is a utility model Figure 2 Enlarged view of point A; Figure 4 This is a side view of an embodiment of the present utility model; Figure 5 This is a utility model Figure 4 DD sectional view.

[0019] In the figure: 1. Driven shaft; 2. Mounting base; 21. Sleeve; 211. First slot; 22. Clutch disc; 222. First inclined groove; 223. Second inclined groove; 23. Pressure plate; 3. Friction plate assembly; 31. First friction plate; 311. First locking block; 32. Second friction plate; 321. Second locking block; 4. Sleeve housing; 41. Second slot; 5. Elastic reset element; 61. First roller; 62. Second roller; 7. Bushing. Detailed Implementation

[0020] The technical solution of this utility model will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings. Example

[0021] like Figures 1 to 5 The illustrated double-groove roller clutch is particularly suitable as an automatic centrifugal clutch for motorcycles. The clutch includes a driven shaft 1, a mounting base 2, a friction plate assembly 3, a housing 4, a resilient reset element 5, a plurality of first rollers 61, and a plurality of second rollers 62.

[0022] The driven shaft 1 is the power output end of the clutch. In actual use, it is connected to the input shaft of the motorcycle's gearbox to transmit power to the rear wheel.

[0023] The mounting base 2 is rotatably fitted onto the driven shaft 1 to receive rotational power from an external power source such as an engine. Specifically, the mounting base 2 includes a bushing 7, a sleeve 21, a clutch disc 22, and a pressure plate 23. The bushing 7 is rotatably fitted onto the driven shaft 1 via bearings, and its outer end is used to fixally connect to a driven wheel (e.g., a sprocket or pulley). The driven wheel is connected to the drive wheel on the engine crankshaft via a chain or belt. The sleeve 21 and the clutch disc 22 are integrally formed. The sleeve 21 and the bushing 7 are connected by the pressure plate 23. Specifically, the pressure plate 23 has a non-circular hole (or a spline hole) at its center, and the outer wall of the bushing 7 has a non-circular mating section (or spline section) that matches the shape of the non-circular hole. During assembly, the pressure plate 23 is first fixedly connected to the sleeve 21, and then the entire structure is fitted onto the bushing 7, so that the mating section of the bushing 7 passes into the non-circular hole of the pressure plate 23, thereby realizing the transmission connection between the bushing 7 and the mounting base 2. The pressure plate 23 is fixedly located at the other end of the sleeve 21 away from the clutch plate 22, and the friction plate assembly 3 is located between the clutch plate 22 and the pressure plate 23.

[0024] On the outer wall of the sleeve 21, several first grooves 211 extending axially are formed along its circumference. The clutch disc 22 has several first inclined grooves 222 around its axis, and a second inclined groove 223 is provided between two adjacent first inclined grooves 222. The first inclined grooves 222 correspond to and are connected to the first grooves 211 on the outer wall of the sleeve 21. The depth direction of both the first inclined grooves 222 and the second inclined grooves 223 is inclined to the axial direction of the clutch disc 22, that is, the bottom of the groove is close to the axis, and the opening of the groove is away from the axis and inclined towards the pressure plate 23.

[0025] The friction plate assembly 3 is sleeved on the sleeve 21 and located between the clutch disc 22 and the pressure plate 23. The friction plate assembly 3 includes at least one first friction plate 31 and at least one second friction plate 32 arranged alternately. The first friction plate 31 is the driving plate, and its inner hole edge has several first locking blocks 311 protruding inward to match the first locking groove 211. The first locking blocks 311 are slidably engaged in the first locking groove 211, so that the first friction plate 31 can both rotate with the mounting base 2 and slide axially. The second friction plate 32 is the driven plate, and its outer ring has several second locking blocks 321 protruding outward.

[0026] The housing 4 is an open-end cover that is fixedly fitted onto the driven shaft 1. Several axially extending second slots 41 are provided on the cylindrical sidewall of the housing 4. The second locking blocks 321 of each second friction plate 32 are correspondingly slidably engaged within the second slots 41, allowing the second friction plate 32 to rotate with the housing 4 and the driven shaft 1, and also to slide axially.

[0027] The elastic reset member 5 is coaxially sleeved on the sleeve 21 and is used to apply an elastic force to the friction plate assembly 3, causing the friction plates to tend to separate in the non-working state. In this embodiment, the elastic reset member 5 is a wave spring, and its number is the same as that of the second friction plates 32. Each elastic reset member 5 is located in the inner hole of one of the second friction plates 32. The outer diameter of the elastic reset member 5 is smaller than the inner hole diameter of the second friction plate 32, so that it is radially supported between the inner hole of the second friction plate 32 and the outer wall of the sleeve 21, which not only plays a role in radial centering of the second friction plate 32, but also keeps the second friction plate 32 and the sleeve 21 coaxial. The elastic reset member 5 is elastically clamped between adjacent first friction plates 31, or between the first friction plate 31 and the pressure plate 23, or between the first friction plate 31 and the clutch plate 22. When the clutch is not engaged, the elastic force of the elastic reset member 5 will force the first friction plates 31 and the second friction plates 32 to separate from each other, forming a gap and cutting off the power transmission.

[0028] A plurality of first rollers 61 are rolled in each of the first inclined grooves 222, and a plurality of second rollers 62 are rolled in each of the second inclined grooves 223. Both the first rollers 61 and the second rollers 62 are cylinders (or spheres). The weight of the second rollers 62 is less than the weight of the first rollers 61. When the first rollers 61 and the second rollers 62 are at the bottom of their respective grooves, a gap is left between their upper ends and the end of the clutch disc 22, meaning that the axial distance between them and the adjacent friction plate assembly 3 is similar.

[0029] The working process of this utility model is divided into three stages: Separated State: When the engine is idling or at low speed, the mounting base 2 rotates at very low speed, and the centrifugal force on the first roller 61 and the second roller 62 is very small, so they both remain at the bottom of their respective inclined grooves. At this time, under the elastic force of the elastic reset member 5, the first friction plate 31 and the second friction plate 32 separate from each other, with a gap existing. The clutch is in the disengaged state, and power is not transmitted.

[0030] Pre-compression state: When the vehicle starts, the rotational speed of the mounting base 2 begins to increase, and the centrifugal force gradually increases. Since the weight of the second roller 62 is less than that of the first roller 61, at the same rotational speed, the centrifugal force on the second roller 62 is sufficient to make it roll outward along the second inclined groove 223 before the first roller 61. Furthermore, since the axial distance between the second roller 62 and the friction plate assembly 3 is similar to that of the first roller 61, the upper end of the second roller 62 quickly contacts the adjacent friction plate and pushes against the friction plate assembly 3, eliminating the gaps between the friction plates and giving the friction plate assembly 3 a pre-compression. At this time, the first roller 61 has not yet moved or has only moved slightly.

[0031] Fully engaged state: As the vehicle starts and the engine speed increases further, the centrifugal force continues to increase. Since the second roller 62 has already provided preload to the friction plate assembly 3, the gap between the friction plates has been eliminated. The first roller 61 can roll outward along the first inclined groove 222 without requiring too much centrifugal force, and together with the second roller 62, presses the first friction plates 31 and the second friction plates 32 axially between the clutch disc 22 and the pressure plate 23. At this time, the power of the rotating mounting seat 2 is transmitted from the first friction plate 31 to the second friction plate 32 through friction, and then from the second friction plate 32 to the housing 4, ultimately driving the driven shaft 1 to rotate, achieving full engagement and transmission of power.

[0032] When the engine speed decreases, the centrifugal force decreases, and the first roller 61 and the second roller 62 gradually return to their respective inclined grooves under the elastic force of the elastic reset member 5 or by their own weight. The friction plates separate again, and the clutch cuts off the power transmission.

[0033] Through the above structure and working process, the clutch in this embodiment achieves sequential actuation by using two-stage rollers of different weights. The second roller eliminates the gap first and provides pre-pressure, enabling the first roller to complete the clamping engagement more quickly when the speed increases, which significantly increases the engagement speed of the clutch and makes the engagement process smoother, reducing shock and jerking.

Claims

1. A dual-groove roller clutch characterized by: include: Driven shaft (1); Mounting base (2) is rotatably sleeved on the driven shaft (1) for receiving external rotational power; the mounting base (2) includes a sleeve (21) and a clutch disc (22) fixedly disposed at one end of the sleeve (21); the clutch disc (22) has a plurality of first inclined grooves (222) around its axis, and a second inclined groove (223) is provided between two adjacent first inclined grooves (222). Friction pad assembly (3) is sleeved on the sleeve (21); The housing (4) is fixedly sleeved on the driven shaft (1); A number of first rollers (61) are rolled in each of the first inclined grooves (222) in a corresponding manner; Several second rollers (62) are rolled in each of the second inclined grooves (223) in a corresponding manner. The weight of the second roller (62) is less than that of the first roller (61), and when the first roller (61) and the second roller (62) are at the bottom of their respective grooves, the axial distance between their upper ends and the friction plate assembly (3) is similar.

2. The dual-groove roller clutch of claim 1, wherein: The friction plate assembly (3) includes at least one first friction plate (31) and at least one second friction plate (32) alternately stacked. The first friction plate (31) is engaged with the sleeve (21) in a manner that allows axial sliding and circumferential linkage, and the second friction plate (32) is engaged with the housing (4) in a manner that allows axial sliding and circumferential linkage.

3. The dual-groove roller clutch of claim 2, wherein: The outer wall of the sleeve (21) is provided with a plurality of first slots (211) extending along its axial direction. The inner hole of the first friction plate (31) is provided with a first block (311) that slides and engages with the first slot (211). The outer ring of the second friction plate (32) is provided with a second block (321). The side wall of the sleeve (4) is provided with a plurality of second slots (41) extending along its axial direction. The second block (321) of each second friction plate (32) slides and engages with each second slot (41).

4. The double-groove roller clutch according to claim 3, characterized in that: The first inclined groove (222) is correspondingly provided and connected to the first slot (211) extending axially on the outer wall of the sleeve (21).

5. The double-groove roller clutch according to claim 1, characterized in that: The mounting base (2) also includes a pressure plate (23), which is fixedly disposed at the other end of the sleeve (21) away from the clutch disc (22), and the friction plate assembly (3) is located between the clutch disc (22) and the pressure plate (23).

6. The double-groove roller clutch according to claim 5, characterized in that: The mounting base (2) also includes a bushing (7). The sleeve (21) is connected to the bushing (7) through the pressure plate (23). The bushing (7) is rotatably mounted on the driven shaft (1). The bushing (7) is used to receive external rotational power and transmit the power to the sleeve (21).

7. The double-groove roller clutch according to claim 1, characterized in that: The first roller (61) and the second roller (62) are cylinders or spheres.

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