Automobile transmission belt wheel structure with anti-off function

Abstract

The application relates to the technical field of tensioning wheels and discloses an automobile transmission belt wheel structure with a falling-off prevention function, which comprises a fixed support piece, a pivot fixedly arranged on the fixed support piece and defining a first axis, an intermediate element sleeved outside the pivot and swinging around the first axis, a belt wheel supported on the intermediate element through a bearing and rotating around a second axis, the second axis being parallel to the first axis and not coinciding with the first axis, and an elastic element acting between the intermediate element and the fixed support piece and used for driving the intermediate element to swing around the first axis so that the belt wheel is pressed against a belt, wherein the automobile transmission belt wheel structure further comprises an eccentric wedge block ring arranged between the pivot and the intermediate element, the eccentric wedge block ring has an outer cylindrical surface, an inner tapered surface matched with an outer tapered surface of the pivot, a fixed eccentric distance existing between the axis of the inner tapered surface and the axis of the outer cylindrical surface, and the eccentric wedge block ring slides on the pivot in the axial direction and generates a radial damping force through the contact between the inner tapered surface and the outer tapered surface.

Description

Technical Field

[0001] This invention relates to the technical field of tensioners, and more particularly to a structure for an automotive transmission belt pulley with an anti-derailment function. Background Technology

[0002] Tensioners are indispensable retaining devices in belt and chain drive systems, widely used in various mechanical transmission scenarios. Their core function is to regulate the tension of the belt and chain in real time during transmission, maintaining it within a reasonable range. This effectively prevents belt slippage and detachment, and also prevents chain tooth skipping and breakage, thereby reducing wear on sprockets, chains, and belts. This ensures smooth and efficient operation of the transmission system and extends the service life of all transmission components.

[0003] Patent CN108916332A discloses an automotive belt tensioner, comprising a pulley, a dust cover, a central pivot arm, a spring chamber, a bushing, and a damping plate. The spring chamber has a centrally located, conductive shaft cavity, and a spring cavity coaxially arranged on the outer side of the shaft cavity. A spring is housed within the spring cavity, with its top end abutting the bottom of the spring cavity and the top end of the spring abutting the bushing. The upper surface of the bushing is fitted with the damping plate. A main shaft passes through the shaft cavity, and a central pivot arm is fitted onto the upper end of the main shaft. The central pivot arm covers the spring chamber and presses against the damping plate. The upper end of the central pivot arm has a shaft hole, and its upper end is connected to the pulley via bolts. The end face of the pulley is located on the dust cover, which is fastened to the upper end face of the pulley by the bolts.

[0004] The existing technology has the following drawbacks: Existing automotive transmission pulley structures generally exhibit certain technical limitations during long-term operation. Most traditional structures employ conventional tensioning and damping methods, with damping control mechanisms often fixed, making it difficult to adapt to dynamic tension changes under varying loads and operating conditions. This frequently leads to a mismatch between damping force and actual requirements, resulting in insufficient transmission stability. Regarding anti-loosening locking, existing solutions have relatively simple limiting structures, which are prone to loosening or displacement of connecting parts under the vibrations and impacts of long-term vehicle operation, thus affecting tension accuracy and structural reliability. Furthermore, some pulleys lack effective automatic alignment mechanisms, making the belt prone to lateral shift during operation, accelerating belt wear, and shortening service life. The overall design still has room for improvement in terms of adaptive adjustment and long-term operational stability. Summary of the Invention

[0005] In view of the above-mentioned problems in the existing technology, a car transmission belt pulley structure with anti-detachment function is proposed.

[0006] One aspect of this application provides an automotive transmission pulley structure with anti-slip function, the purpose of which is to solve the problems of belt loosening, insufficient damping adjustment flexibility, and poor structural stability that traditional pulley structures are prone to under long-term working conditions, and to achieve adaptive adjustment of belt tension and anti-slip locking.

[0007] The technical solution of the present invention is: a car transmission belt pulley structure with anti-detachment function, including a fixed support member; A pivot is fixedly mounted on the fixed support member and defines a first axis. An intermediate element is fitted outside the pivot and swings about the first axis; The pulley is supported on the intermediate element by bearings and rotates about a second axis, which is parallel to and does not coincide with the first axis. An elastic element, acting between the intermediate element and the fixed support, drives the intermediate element to swing around the first axis, so that the pulley presses against the belt. It also includes an eccentric wedge ring, which is disposed between the pivot and the intermediate element, and the outer wall of the pivot is provided with an outer conical surface; The eccentric wedge ring has: The outer cylindrical surface is connected to the inner hole of the intermediate element; The inner conical surface mates with the outer conical surface of the pivot; There is a fixed eccentricity between the axis of the inner conical surface and the axis of the outer cylindrical surface, so that the wall thickness of the eccentric wedge ring changes continuously along the circumference. The eccentric wedge ring slides axially on the pivot and generates radial damping force through the contact between the inner conical surface and the outer conical surface.

[0008] Furthermore, it also includes an axial elastic group, disposed at the upper end of the eccentric wedge ring, for applying an initial axial preload to the eccentric wedge ring.

[0009] Furthermore, the axial elastic group is at least one compression spring or a set of disc springs.

[0010] Furthermore, it also includes a wedge-shaped locking ring, which is disposed at the upper end of the eccentric wedge block ring; The wedge-shaped locking ring has a first inclined surface, which cooperates with a second inclined surface correspondingly provided on the fixed support member, and is used to restrict the eccentric wedge ring from moving in the opposite direction along the axial direction.

[0011] Furthermore, it also includes a damping adjusting nut, which is disposed at the end of the pivot and abuts against one end of the axial elastic group, for adjusting the axial preload of the eccentric wedge ring from the outside.

[0012] Furthermore, the semi-cone angle of the inner conical surface of the eccentric wedge ring is 8° to 15°.

[0013] Furthermore, the eccentricity of the eccentric wedge ring is 2mm to 5mm.

[0014] Furthermore, the pulley is a convex pulley, with its outer circumferential surface forming an outwardly convex arc-shaped surface along the axial direction, used to guide the belt to automatically center.

[0015] Furthermore, when the belt applies tension to the pulley, the tendency of the intermediate element to swing around the first axis is transformed into an axial component force acting on the eccentric wedge ring through the eccentric geometric relationship between the outer cylindrical surface and the inner conical surface of the eccentric wedge ring. This axial component force is proportional to the belt tension, thereby automatically increasing the normal pressure between the inner conical surface and the outer conical surface, and realizing the damping torque adaptively increasing with the belt tension.

[0016] The beneficial effects of this invention are: Achieving adaptive adjustment of damping torque: Through the eccentric geometric design of the eccentric wedge ring, the belt tension can be converted into the axial component force of the eccentric wedge ring, so that the damping torque increases or decreases adaptively with the belt tension, ensuring that the belt is always in a stable tension state and effectively preventing belt slippage.

[0017] It has a reliable anti-loosening locking function: the wedge-shaped locking ring and the inclined surface of the fixed support are matched, and the double limit of the fixed nut and the shaft step can effectively limit the axial reverse movement of the eccentric wedge ring, prevent the structure from loosening under vibration conditions, and improve the long-term operational reliability.

[0018] The damping is flexibly adjustable: by using the pivot thread section and the damping adjustment nut, the preload of the axial elastic component can be adjusted from the outside, thereby adjusting the basic damping size to adapt to different working conditions and improve the versatility of the structure.

[0019] Reduce belt wear and extend service life: The pulley adopts a convex arc surface design, which can guide the belt to automatically center itself, avoid lateral belt deviation, reduce wear, and at the same time, the damping structure reduces vibration and impact, further extending the service life of the belt and the overall structure. Attached Figure Description

[0020] Figure 1 This is a perspective view of the automotive transmission belt pulley structure with anti-detachment function according to the present invention; Figure 2 For the present invention Figure 2 Top view; Figure 3 For the present invention Figure 2 Sectional view at point AA; Figure 4This is an exploded view showing the installation of the connecting components in the automotive transmission belt pulley structure with anti-detachment function of the present invention.

[0021] In the picture: 1. Fixed support; 2. Pivot; 3. Intermediate element; 4. Pulley; 5. Bearing; 6. Elastic element; 7. Eccentric wedge ring; 8. Outer conical surface; 9. Outer cylindrical surface; 10. Inner conical surface; 11. Axial elastic group; 12. Wedge locking ring; 13. Inclined surface one; 14. Inclined surface two; 15. Damping adjusting nut; A. First axis; B. Second axis; e. Eccentricity; 16. Base plate; 17. Support plate; 18. Mounting groove; 19. Threaded section; 20. Fixing nut. Detailed Implementation

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] Example, refer to Figures 1-4 This invention provides an automotive transmission pulley structure with anti-detachment function. The structure includes a fixed support 1, a pivot 2, an intermediate element 3, a pulley 4, an elastic element 6, an eccentric wedge ring 7, an axial elastic assembly 11, a damping adjusting nut 15, and a wedge-shaped locking ring 12. The pivot 2 is fixedly mounted on the fixed support 1, and together they form the mounting base of the entire structure, defining a first axis A, providing a reference for the assembly and movement of each moving component. The intermediate element 3 is sleeved on the outside of the pivot 2 and can swing around the first axis A. The upper part of the intermediate element 3 is a cylindrical structure, and the axis of this cylindrical structure is defined as a second axis B. A base plate 16 extends from the bottom of the intermediate element 3, supporting a bearing 5. The pulley 4 is supported on the intermediate element 3 by the bearing 5 and can rotate around the second axis B. The second axis B is parallel to and does not coincide with the first axis A, forming an eccentric arrangement, thereby ensuring that the pulley 4 can generate a corresponding movement tendency under belt tension. The elastic element 6 is installed between the intermediate element 3 and the fixed support 1. The elastic element 6 provides driving force for the intermediate element 3 to swing around the first axis A, driving the intermediate element 3 to swing, thereby driving the pulley 4 to press the transmission belt and maintain the continuous tension of the belt.

[0024] The core improvement of this embodiment lies in the addition of an eccentric wedge ring 7, which is positioned between the pivot 2 and the intermediate element 3. The outer wall of the pivot 2 has an outer conical surface 8, and the eccentric wedge ring 7 has a corresponding outer cylindrical surface 9 and an inner conical surface 10. The outer cylindrical surface 9 of the eccentric wedge ring 7 connects to the inner hole of the intermediate element 3, enabling their assembly and positioning. The inner conical surface 10 engages with the outer conical surface 8 of the pivot 2, and relative rotation between the inner and outer conical surfaces is possible. To ensure damping effect, the inner and outer conical surfaces 10 are made of a damping material, thereby improving the frictional damping performance of the conical mating pair through material properties. A fixed eccentricity e is provided between the axis of the inner conical surface 10 and the axis of the outer cylindrical surface 9 of the eccentric wedge ring 7. This eccentricity e design makes the wall thickness of the eccentric wedge ring 7 continuously change along its circumference. The eccentric wedge ring 7 can slide along the axial direction of the pivot 2. During the sliding process, the inner conical surface 10 and the outer conical surface 8 come into contact with each other and squeeze, thereby generating radial damping force and realizing the control of the motion damping of the pulley 4. A receiving plate 17 is also provided at the bottom of the eccentric wedge ring 7. The bottom plate 16 is engaged in the receiving plate 17. The bottom of the receiving plate 17 is also provided with a mounting groove 18 for fixing the elastic element 6.

[0025] To achieve damping preload and adjustment, this embodiment also includes an axial elastic assembly 11 and a damping adjusting nut 15. The axial elastic assembly 11 is located at the upper end of the eccentric wedge ring 7 and is used to apply an initial axial preload to the eccentric wedge ring 7. An annular groove is formed at the top of the eccentric wedge ring 7 for mounting and positioning the axial elastic assembly 11. The axial elastic assembly 11 can employ at least one compression spring or a set of disc springs, providing a stable preload through the elastic action of the elastic components. The damping adjusting nut 15 is located at the end of the pivot 2. The upper end of the pivot 2 is constructed as a threaded section 19, which engages with the damping adjusting nut 15. One end of the damping adjusting nut 15 abuts against the axial elastic assembly 11. The operator can adjust the preload applied to the axial elastic assembly 11 from outside the structure by rotating the damping adjusting nut 15, thereby changing the clamping force of the eccentric wedge ring 7 on the conical surface of the pivot 2 and adjusting the basic damping magnitude.

[0026] To address the anti-loosening locking function of the structure, this embodiment includes a wedge-shaped locking ring 12. The wedge-shaped locking ring 12 is fitted onto the threaded section 19 of the pivot 2 and is located at the upper end of the eccentric wedge ring 7. The lower end of the wedge-shaped locking ring 12 has a first inclined surface 13, and a second inclined surface 14 is correspondingly positioned on the fixed support 1. The first inclined surface 13 and the second inclined surface 14 cooperate with each other, and through the abutment and limiting between the inclined surfaces, the eccentric wedge ring 7 is restricted from moving in the opposite direction along the axial direction, preventing the structure from loosening under vibration conditions. To further secure the wedge-shaped locking ring 12, a fixing nut 20 is provided above the wedge-shaped locking ring 12. The fixing nut 20 cooperates with the threaded section 19 of the pivot 2 to achieve axial positioning of the wedge-shaped locking ring 12. The lower end of the pivot 2 has a shaft step, which abuts against the wedge-shaped locking ring 12, cooperating with the fixing nut 20 to complete the limiting of the wedge-shaped locking ring 12 in both axial directions, improving the reliability of the locking structure.

[0027] In this embodiment, the pulley 4 is preferably a convex pulley 4, whose outer circumferential surface is constructed as an outwardly convex arc surface along the axial direction. This arc surface structure can guide the belt during belt transmission, guide the belt to automatically center, avoid the risk of increased wear and fall-off caused by belt deviation during operation, and further improve the stability of the entire transmission structure.

[0028] The working principle of this embodiment is as follows: In the initial state, by rotating the damping adjustment nut 15, the axial elastic group 11 is pushed to produce elastic deformation, thereby applying an initial axial preload to the eccentric wedge ring 7. The eccentric wedge ring 7 is pressed axially along the pivot 2 and its conical mating pair with the pivot 2. A radial pressing force is generated between the conical mating pairs, thereby forming the basic damping torque. At the same time, the wedge locking ring 12, through the inclined surface mating and the limiting effect of the fixed nut 20 and the shaft step, firmly locks the eccentric wedge ring 7, preventing it from axially loosening under the vibration conditions of vehicle driving, and ensuring the initial stability of the structure.

[0029] When the drive belt applies tension to pulley 4, the force on pulley 4 causes the intermediate element 3 to tend to oscillate around the first axis A. This oscillation tendency is converted into an axial component force acting on the eccentric wedge ring 7 through the eccentric geometric relationship between the outer cylindrical surface 9 and the inner conical surface 10 of the eccentric wedge ring 7. This axial component force is proportional to the belt tension. As the axial component force increases, the clamping force of the eccentric wedge ring 7 on the outer conical surface 8 of the pivot 2 further increases, resulting in an increase in the normal force between the inner conical surface 10 and the outer conical surface 8. This achieves an adaptive increase in the damping torque with the belt tension. Conversely, when the belt tension decreases, the oscillation tendency of the intermediate element 3 weakens, the converted axial component force decreases accordingly, the clamping force of the eccentric wedge ring 7 decreases, and the damping torque also automatically decreases. Through this adaptive adjustment mechanism, regardless of the belt tension, the damping and clamping force can be adjusted in a timely manner to ensure that the belt is always in a stable tension state, effectively preventing belt slippage and improving the service life and operational reliability of the entire automotive drive pulley 4 structure.

[0030] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A vehicle transmission belt pulley structure with anti-derailment function, comprising: Fixed support (1); Pivot (2) is fixedly mounted on the fixed support (1) and defines the first axis (A); The intermediate element (3) is sleeved outside the pivot (2) and swings about the first axis (A); The pulley (4) is supported on the intermediate element (3) by the bearing (5) and rotates about the second axis (B), which is parallel to and does not coincide with the first axis (A); An elastic element (6) acts between the intermediate element (3) and the fixed support (1) to drive the intermediate element (3) to swing around the first axis (A) so that the pulley (4) presses the belt, characterized in that: It also includes an eccentric wedge ring (7), which is disposed between the pivot (2) and the intermediate element (3), and the outer wall of the pivot (2) is provided with an outer conical surface (8). The eccentric wedge ring (7) has: The outer cylindrical surface (9) is connected to the inner hole of the intermediate element (3); The inner conical surface (10) mates with the outer conical surface (8) of the pivot (2); There is a fixed eccentricity (e) between the axis of the inner conical surface (10) and the axis of the outer cylindrical surface (9), so that the wall thickness of the eccentric wedge ring (7) changes continuously along the circumferential direction. The eccentric wedge ring (7) slides axially on the pivot (2) and generates radial damping force through the contact between the inner conical surface (10) and the outer conical surface (8).

2. The automotive transmission belt pulley structure with anti-detachment function according to claim 1, characterized in that: It also includes an axial elastic group (11), which is disposed at the upper end of the eccentric wedge ring (7) and is used to apply an initial axial preload to the eccentric wedge ring (7).

3. The automotive transmission belt pulley structure with anti-detachment function according to claim 2, characterized in that: The axial elastic group (11) is at least one compression spring or a group of disc springs.

4. The automotive transmission belt pulley structure with anti-detachment function according to claim 1, characterized in that: It also includes a wedge-shaped locking ring (12), which is disposed at the upper end of the eccentric wedge ring (7); The wedge-shaped locking ring (12) has an inclined surface (13) that cooperates with the inclined surface (14) correspondingly provided on the fixed support (1) to restrict the eccentric wedge ring (7) from moving in the opposite direction along the axial direction.

5. The automotive transmission belt pulley structure with anti-detachment function according to claim 2, characterized in that: It also includes a damping adjustment nut (15), which is located at the end of the pivot (2) and abuts against one end of the axial elastic group (11) for adjusting the axial preload of the eccentric wedge ring (7) from the outside.

6. The automotive transmission belt pulley structure with anti-detachment function according to claim 1, characterized in that: The semi-cone angle of the inner conical surface (10) of the eccentric wedge ring (7) is 8° to 15°.

7. The automotive transmission belt pulley structure with anti-detachment function according to claim 1, characterized in that: The eccentricity (e) of the eccentric wedge ring (7) is 2 mm to 5 mm.

8. The automotive transmission belt pulley structure with anti-detachment function according to claim 1, characterized in that: The pulley (4) is a convex pulley, and its outer circumferential surface is an outwardly convex arc surface along the axial direction, which is used to guide the belt to automatically center.

9. The automotive transmission belt pulley structure with anti-detachment function according to claim 1, characterized in that: When the belt applies tension to the pulley (4), the tendency of the intermediate element (3) to swing around the first axis (A) is transformed into an axial component force acting on the eccentric wedge ring (7) through the eccentric geometric relationship between the outer cylindrical surface (9) and the inner conical surface (10) of the eccentric wedge ring (7). This axial component force is proportional to the belt tension, thereby automatically increasing the normal pressure between the inner conical surface (10) and the outer conical surface (8), and realizing the damping torque adaptively increasing with the belt tension.

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