High-reliability metal sliding bearing scroll spring automatic tensioning wheel

Abstract

This utility model discloses a high-reliability metal sliding bearing scroll spring automatic tensioner, belonging to the technical field of tensioner technology. The tensioner includes a spring support sleeve component, a support plate, a pulley, a central bushing, a panel assembly, a scroll spring, and a metal sliding bearing. One end of the central bushing is knurled to the spring support sleeve component, and the other end is fixed to the panel assembly. The support plate is mounted on the central bushing via the metal sliding bearing and can rotate relative to it. The inner surface of the metal sliding bearing is coated with polytetrafluoroethylene (PTFE), and the outer surface of the central bushing is nickel-plated to improve wear resistance. O-rings are provided at both ends of the sliding bearing to enhance sealing and dust prevention. The scroll spring provides tension force, and the double deep groove ball bearings enhance load-bearing capacity. This utility model solves the problems of rapid wear and poor dust prevention in traditional tensioners, and has the advantages of high reliability, long service life, and low maintenance, making it suitable for engine front-end wheel systems.

Description

Technical Field

[0001] This utility model relates to the field of engine tensioner technology, and in particular to a high-reliability metal sliding bearing spiral spring automatic tensioner. Background Technology

[0002] Multi-ribbed belt drives are widely used in engine front-end pulley systems, but belts are friction drives and wear down over time. Traditional fixed tensioning devices cannot automatically compensate for belt tension, leading to low transmission efficiency and high noise when tension is insufficient. To address this, automatic tensioners have been developed, using spring mechanisms to dynamically adjust tension and ensure stable engine operation. However, conventional automatic tensioners often use engineering plastic sliding bearings, which wear quickly under high-frequency dynamic oscillations, easily causing tensioner misalignment and abnormal noise. Furthermore, their dustproof sealing performance is insufficient, allowing impurities to intrude and accelerate wear, making it difficult to meet the high operating conditions (such as high temperature, high speed, and dusty environments) of China VI engines. While existing technologies have attempted to improve bearing materials or sealing structures, the wear resistance and load-bearing capacity of engineering plastic bearings are limited, and sealing designs are often complex or ineffective, affecting the overall reliability and lifespan of the tensioner. Therefore, a highly wear-resistant and highly sealing automatic tensioner solution is urgently needed. Utility Model Content

[0003] The purpose of this invention is to provide a highly reliable automatic tensioner for a metal sliding bearing spiral spring. By employing a structure that combines a metal sliding bearing with a polytetrafluoroethylene coating, nickel plating on the central bushing, O-ring seals, and double deep groove ball bearings, the wear resistance and dustproof performance of the friction surface are significantly improved, reducing the risk of uneven wear, extending the service life of the tensioner, and ensuring stable, efficient, and quiet operation of the engine front-end accessory drive system under harsh operating conditions.

[0004] This utility model is achieved using the following technical solution: a high-reliability metal sliding bearing scroll spring automatic tensioning wheel, characterized in that it includes a spring support sleeve component, a support plate, a pulley, a central bushing, a panel assembly, a scroll spring, and a metal sliding bearing; one end of the central bushing is knurled to the spring support sleeve component, and the other end is connected to the panel assembly; the support plate is mounted on the central bushing via the metal sliding bearing and can rotate relative to it; the inner surface of the metal sliding bearing is coated with polytetrafluoroethylene, and the outer surface of the central bushing is nickel-plated; both ends of the metal sliding bearing are provided with O-rings.

[0005] Furthermore, it also includes a friction-reducing plate, a disc spring, a friction-reducing partition, and a dustproof block; the friction-reducing plate is disposed between the support plate and the panel assembly, and the disc spring is disposed between the friction-reducing partition and the support plate to provide axial preload, thereby pressing the panel assembly, the friction-reducing plate, the friction-reducing partition, and the support plate together; the dustproof block is disposed between the spring support sleeve component and the spiral spring. Furthermore, one end of the support plate is provided with a hook groove for connecting the inner hook of the spiral spring, and the outer hook of the spiral spring is fixed to the limiting block of the spring support sleeve component; a spring washer is provided between each turn of the spiral spring to avoid wear between the turns.

[0006] Furthermore, the metal sliding bearing is made of metal material and is pressed against the support plate by an interference fit. The polytetrafluoroethylene coating is applied to the inner surface of the metal sliding bearing to improve wear resistance and load-bearing capacity.

[0007] Furthermore, the O-rings are positioned at both ends of the metal sliding bearing to achieve contact sealing and prevent dust and impurities from entering the friction parts.

[0008] Furthermore, it also includes a deep groove ball bearing, a shaft bolt, and a dust cover; the other end of the support plate is provided with a bearing positioning structure, at least one deep groove ball bearing is fixed to the support plate by the shaft bolt and cooperates with the pulley; the dust cover is set between the shaft bolt and the deep groove ball bearing to form a sealed dustproof structure.

[0009] Furthermore, there are two deep groove ball bearings, which are pressed side by side onto the support plate by shaft bolts to enhance the load-bearing capacity.

[0010] Furthermore, it also includes an eccentric bushing assembly, positioned between the support plate and the spring support sleeve component, to enhance wear resistance and provide auxiliary sealing function.

[0011] Furthermore, the panel assembly includes a panel, the central bushing is fixedly connected to the panel, and provides axial clamping force through a disc spring.

[0012] Furthermore, it also includes retaining rings, which are used to axially limit the deep groove ball bearing and ensure installation reliability.

[0013] The high-reliability metal sliding bearing spiral spring automatic tensioning wheel of this utility model has the following advantages: The inner surface of the metal sliding bearing is coated with polytetrafluoroethylene, and the outer surface of the central bushing is nickel-plated, forming a low-friction pair, which greatly improves wear resistance and load-bearing capacity. Compared with engineering plastic bearings, the wear rate is reduced, making it suitable for high-frequency oscillating conditions.

[0014] O-rings are installed at both ends of the metal sliding bearing to achieve contact sealing, effectively preventing dust and impurities from entering the friction parts, reducing abnormal wear and uneven wear, and extending the component life.

[0015] The design employs double deep groove ball bearings, which are fixed to the support plate by shaft bolts, thereby improving the overall load-bearing capacity and stability. Disc springs provide axial preload, which presses the panel assembly, friction-reducing plate, etc. tightly together to prevent loosening.

[0016] The dust cover and pulley form a fully sealed space, and the dust plug and labyrinth structure work together to improve protection performance in dusty environments.

[0017] The spiral spring is connected to the support plate via an inner hook and fixed to the spring support sleeve via an outer hook, providing stable torque, automatically compensating for belt extension, and ensuring constant tension. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 A schematic diagram of an automatic tensioning wheel structure for a high-reliability metal sliding bearing spiral spring. Figure 2 for Figure 1 Partial schematic diagram at point I in the middle; In the diagram: 1-Panel assembly, 2-Spring support sleeve component, 3-Rear dustproof assembly, 4-Eccentric bushing assembly, 5-Support plate, 6-Central bushing, 7-Pulley, 8-Friction reduction plate, 9-Panel, 10-Disc spring, 11-Friction reduction partition, 12-Spring, 13-Dustproof plug, 14-Shaft bolt, 15-Dustproof cover, 16-Spring washer, 17-Retaining ring, 18-Sliding bearing, 19-Bearing, 20-O-ring. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Example

[0022] like Figure 1-2As shown, this embodiment provides a high-reliability metal sliding bearing scroll spring automatic tensioning wheel, which mainly consists of a panel assembly 1, a spring support sleeve component 2, a support plate 5, a central shaft sleeve 6, a pulley 7, a friction-reducing plate 8, a panel 9, a disc spring 10, a friction-reducing partition 11, a spring 12, a dustproof plug 13, a shaft bolt 14, a dustproof cover 15, a spring washer 16, a retaining ring 17, a sliding bearing 18, a bearing 19, an O-ring 20, etc.

[0023] One end of the central bushing 6 is interference-fitted to the spring support sleeve component 2 via a knurled structure, and the other end is fixedly connected to the panel assembly 1, thereby assembling the spring support sleeve component 2, support plate 5, and other components into a single unit. The support plate 5, as the rotating component of the tension wheel, is press-fitted to the outer ring of the sliding bearing 18 via an interference fit, while the inner surface of the sliding bearing 18 directly engages with the outer surface of the central bushing 6, allowing the support plate 5 to rotate relative to the central bushing 6. The sliding bearing 18 is made of metal, with a polytetrafluoroethylene coating on its inner surface, significantly improving its load-bearing capacity and wear resistance. Simultaneously, the outer surface of the central bushing 6 is nickel-plated, further enhancing the wear resistance of the friction surface. O-rings 20 are provided at both ends of the sliding bearing 18 to achieve contact sealing, effectively preventing dust and impurities from entering the friction area and reducing the risk of uneven wear.

[0024] One end of the support plate 5 is provided with a hook groove for connecting the inner hook of the spring 12. The outer hook of the spring 12 is fixed to the limiting block of the spring support sleeve component 2, thereby providing a stable tension torque during the operation of the tensioning wheel. The spring 12 is a spiral spring, and a spring washer 16 is provided between each coil of the spring 12 to prevent wear between coils. An eccentric bushing assembly 4 is provided between the support plate 5 and the spring support sleeve component 2 to improve the wear resistance and fit stability between the rotating components and to provide an auxiliary sealing function; the eccentric bushing assembly 4 can be an integral or nested wear-resistant structure. A friction-reducing plate 8 is provided between the support plate 5 and the panel assembly 1. A disc spring 10 is installed between the friction-reducing partition 11 and the support plate 5. The disc spring 10 provides axial preload to press the panel assembly 1, the friction-reducing plate 8, the friction-reducing partition 11 and the support plate 5 tightly together to ensure that the structure does not loosen.

[0025] The other end of the support plate 5 is equipped with a bearing positioning structure. Two deep groove ball bearings 19 are pressed onto the support plate 5 by shaft bolts 14 and cooperate with the pulley 7 to ensure the smooth rotation of the pulley 7. The deep groove ball bearings 19 are arranged in a double row, which has a greater load-bearing capacity than single-row bearings and extends the service life of the tensioner. To enhance dustproof performance, a dust cover 15 is set between the shaft bolts 14 and the bearings 19 to form a fully sealed space; a dustproof plug 13 is set between the limiting block of the spring support sleeve component 2 and the outer hook of the spring 12, and the rear end area is combined with a labyrinth dustproof structure to further enhance the protection capability. The retaining ring 17 is used for axial limiting of the bearings 19 to ensure installation reliability.

[0026] During operation, when the belt of the engine front-end pulley system experiences tension changes due to stretching or wear, the support plate 5 rotates relative to the central bushing 6 via the sliding bearing 18. The spring 12 deforms accordingly, generating a restoring torque to automatically compensate for belt tension and maintain stability. The PTFE coating of the sliding bearing 18 and the nickel-plated surface of the central bushing 6 form a low-friction pair, reducing wear. The sealing design of the O-ring 20 prevents foreign matter intrusion, avoiding accelerated wear. The entire tensioner structure is compact and suitable for high-speed, dusty environments. Through the high wear resistance of the metal sliding bearing and the sealing and dustproof measures, uneven wear is significantly reduced, service life is extended, and reliable, stable, and efficient operation of the engine front-end accessory drive system is ensured.

[0027] The key technical advantages of this design are: the combination of a metal sliding bearing and a PTFE coating significantly improves wear resistance and load-bearing capacity, making it more suitable for the high operating conditions of China VI engines compared to traditional engineering plastic bearings; the optimized sealing structure effectively prevents impurities from entering and reduces abnormal wear; and the double deep groove ball bearing layout enhances overall load-bearing performance, ensuring the tensioner remains stable under dynamic oscillation. Thus, this invention achieves the goals of high reliability, long service life, and low maintenance costs.

[0028] The above embodiments describe the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Modifications and variations made by those skilled in the art without departing from the spirit and scope of this utility model should be protected within the scope of the appended claims.

Claims

1. A high-reliability metal sliding bearing scroll spring automatic tensioning wheel, characterized in that, The assembly includes a spring support sleeve component (2), a support plate (5), a pulley (7), a central bushing (6), a panel assembly (1), a spiral spring (12), and a metal sliding bearing (18). One end of the central bushing (6) is knurled to the spring support sleeve component (2), and the other end is connected to the panel assembly (1). The support plate (5) is mounted on the central bushing (6) via the metal sliding bearing (18) and can rotate relative to it. The inner surface of the metal sliding bearing (18) is coated with polytetrafluoroethylene, and the outer surface of the central bushing (6) is nickel-plated. Both ends of the metal sliding bearing (18) are provided with O-rings (20).

2. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, It also includes a friction-reducing plate (8), a disc spring (10), a friction-reducing partition (11), and a dustproof block (13); the friction-reducing plate (8) is disposed between the support plate (5) and the panel assembly (1), and the disc spring (10) is disposed between the friction-reducing partition (11) and the support plate (5) to provide axial preload force so that the panel assembly (1), the friction-reducing plate (8), the friction-reducing partition (11), and the support plate (5) are pressed together; the dustproof block (13) is disposed between the spring support sleeve component (2) and the spiral spring (12).

3. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, The support plate (5) has a hook groove at one end for connecting the inner hook of the spiral spring (12). The outer hook of the spiral spring (12) is fixed on the limiting block of the spring support sleeve component (2). A spring pad (16) is provided between each turn of the spiral spring (12) to avoid wear between turns.

4. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, The metal sliding bearing (18) is made of metal material and is pressed into the support plate (5) by interference fit. The polytetrafluoroethylene coating is applied to the inner surface of the metal sliding bearing (18) to improve wear resistance and load-bearing capacity.

5. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, The O-rings (20) are placed at both ends of the metal sliding bearing (18) to achieve contact sealing and prevent dust and impurities from entering the friction parts.

6. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, It also includes a deep groove ball bearing (19), a shaft bolt (14) and a dust cover (15); the other end of the support plate (5) is provided with a bearing positioning structure, and at least one deep groove ball bearing (19) is fixed on the support plate (5) by the shaft bolt (14) and cooperates with the pulley (7); the dust cover (15) is set between the shaft bolt (14) and the deep groove ball bearing (19) to form a sealed dustproof structure.

7. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 6, characterized in that, Two deep groove ball bearings (19) are press-fitted side-by-side onto the support plate (5) by shaft bolts (14) to enhance the load-bearing capacity.

8. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, It also includes an eccentric bushing assembly (4), which is located between the support plate (5) and the spring support sleeve component (2) to improve wear resistance and sealing auxiliary function.

9. The high-reliability metal sliding bearing spiral spring automatic tensioning wheel according to claim 1, characterized in that, The panel assembly (1) includes a panel (9), the central bushing (6) is fixedly connected to the panel (9), and provides axial clamping force through a disc spring (10).

10. A high reliability metal sliding bearing scroll spring automatic tensioning wheel according to claim 1, characterized in that, It also includes a retaining ring (17) for axially limiting the deep groove ball bearing (19) to ensure installation reliability.

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