Closed maintenance-free torque-limited slip clutch

Abstract

This invention discloses a closed, maintenance-free, torque-limiting sliding clutch, relating to the field of key agricultural machinery components. It includes a driven disc with friction plates fixed on both sides, and a disc hub riveted to the driven disc to form a first assembly; a housing A with a bearing B pressed into its inner hole to form a second assembly; housing B with a bearing A pressed into its inner hole to form a third assembly; and a drive shaft with a bushing fitted on it, and a pressure plate fitted around the bushing. Housings A and B are riveted together to form a closed inner cavity. The drive shaft passes through housings A and B sequentially. The first assembly is placed into the inner cavity and fitted onto the drive shaft. A support ring is embedded in the inner wall of housing B, and a diaphragm spring is positioned between the support ring and the pressure plate. This invention employs a closed structure, using a diaphragm spring instead of a compression spring to provide clamping force. Even when the friction plates wear to their limit, the clamping force remains largely unchanged, thus requiring virtually no maintenance during the product's service life.

Description

Technical Field

[0001] This invention relates to the field of key components for agricultural machinery, specifically to a closed, maintenance-free, torque-limiting sliding clutch. Background Technology

[0002] In the transmission system of the front accessories of a combine harvester, in order to prevent overload of the transmission system caused by blockage or other reasons, a sliding clutch is required to transmit torque. Since it is in a constantly engaged state and does not require a disengagement device, when the impact torque exceeds the set limit, the sliding clutch slips to limit the transmission of overload torque and protect the components in the transmission system from damage.

[0003] like Figure 13 , 14 As shown, the existing conventional sliding clutch installation relationship is as follows: the friction plate (4') and the steel back (2') are bonded together to form component one; the two inner bushings (12') are pressed into the inner hole of the outer bushing (1') and the oil nozzle (8') is installed to form component two; the outer bushing (13'), component one, and the front cover (5') are sequentially assembled on the inner bushing (3'), and the six bolts (11') are sequentially assembled with flat washers (9'), spring A (6'), and spring B (7') and passed through the through hole on the front cover to press component one onto the inner bushing, and the retaining rings (10') are sequentially inserted into the small holes of the heads of the two adjacent bolts to form component three; component two and component three are assembled together to form a sliding clutch assembly, and the steel back and the outer bushing are locked together with locking washers (14') and mounting bolts (15'). The torque transmission route of this conventional slipper clutch is as follows: shaft 1 → inner bushing → bolt → spring → front cover → friction plate → steel back → outer bushing → pulley. It requires the cooperation of multiple parts and the transmission route is long. If any part fails or is damaged, the clutch will fail.

[0004] Because conventional slipper clutches do not employ a closed structure, most components, such as spring A, spring B, and the front cover, are directly exposed to the air. Combine harvesters generate a large amount of dust and dirt during harvesting, and are essentially not cleaned throughout a harvest season. This type of structure makes it difficult to guarantee the normal operation of combine harvesters under these operating conditions and in diverse climates worldwide.

[0005] Furthermore, conventional slipper clutches use six springs A and six springs B to provide clamping force, which brings many difficulties to product assembly and adjustment. During use, as the friction plates wear, the compression springs gradually elongate, causing the clamping force to rapidly decline and rendering the clutch unusable. Frequent spring readjustment is necessary, which is time-consuming, labor-intensive, and difficult to restore to its initial working state. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a closed, maintenance-free, torque-limiting sliding clutch. This sliding clutch, through a novel design, employs a closed structure within its permissible dimensional space to minimize the impact of combine harvester operating conditions and environmental factors on product performance, making the product safer and more stable to use. Furthermore, a diaphragm spring is used instead of a compression spring to provide the clamping force. The diaphragm spring has excellent non-linear characteristics; with proper design, even when the friction plates wear to their limit, the clamping force remains largely unchanged, thus requiring virtually no maintenance during the product's service life.

[0007] The objective of this invention is achieved through the following technical solution: this closed-loop, maintenance-free, torque-limiting slip clutch includes...

[0008] A friction plate is fixed on each of the two surfaces of the driven disc. A hub is installed in the inner hole of the driven disc and the hub is riveted to the driven disc to form the first component.

[0009] Cover A, bearing B is pressed into the inner hole of cover A to form the second component;

[0010] Housing B, bearing A is pressed into the inner hole of housing B to form a third component; and

[0011] A drive shaft, on which a bushing is fitted, and a pressure plate is fitted around the outer periphery of the bushing;

[0012] The housing A of the second component and the housing B of the third component are aligned and riveted together to form a closed inner cavity. The drive shaft passes through housing A and housing B in sequence and is supported on bearings A and B. The first component is placed into the inner cavity and mounted on the drive shaft through a hub. A support ring is embedded in the inner wall of housing B. A diaphragm spring is provided between the support ring and the pressure plate to apply pressure to the pressure plate, so that the pressure plate presses the friction plate on one side of the driven plate, and the friction plate on the other side of the driven plate is pressed against the inner wall of housing A.

[0013] As a further technical solution, the drive shaft engages with the inner spline of the disc hub via an external spline.

[0014] As a further technical solution, a disc spring is placed between the inner hole of the cover B and one side end face of the bearing A, so that the bushing is pressed between the other side end face of the bearing A and the end face of the external spline.

[0015] As a further technical solution, a disc spring is placed between the inner hole of the cover A and one end face of the bearing B, and a wave washer is placed between the other end face of the bearing B and the end face of the external spline.

[0016] As a further technical solution, the outer wall of the pressure plate is provided with a spline groove, which is used to cooperate with the internal teeth on the inner wall of the cover B.

[0017] As a further technical solution, an annular groove is formed on the inner wall of the cover B for inserting the support ring.

[0018] As a further technical solution, sealant is applied to the mounting surfaces of the housing A and housing B.

[0019] The beneficial effects of this invention are as follows:

[0020] 1. Considering the operating conditions and environment of combine harvesters, which have extremely high requirements for corrosion resistance, a closed structure design is adopted. The surfaces of cover A and cover B are treated with anti-rust paint and sealant to increase rust and corrosion resistance and effectively improve the service life of the clutch.

[0021] 2. Adopting a diaphragm spring structure, based on the design principle of clutch diaphragm springs, due to the excellent non-linear characteristics of diaphragm springs, the clamping force can still maintain minimal change within the service life of the friction plates (wear ≤3mm), basically requiring no adjustment or maintenance, thus improving product reliability and convenience;

[0022] 3. The drive shaft is fixed at both ends with wave washers, bushings and bearings respectively mounted on housing A and housing B. The wave washers can eliminate the assembly gap between the components, and the gap between the bearing and the housing is eliminated by installing disc springs, which can ensure the clamping force and improve the sealing performance. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the main structure of the first component in this invention.

[0024] Figure 2 for Figure 1 AA sectional view.

[0025] Figure 3 This is a schematic diagram of the main structure of the second component in this invention.

[0026] Figure 4 for Figure 3 BB cross-sectional view.

[0027] Figure 5 This is a schematic diagram of the main structure of the third component in this invention.

[0028] Figure 6 for Figure 5 CC section view.

[0029] Figure 7 This is a schematic diagram of the main structure of the present invention.

[0030] Figure 8 for Figure 7 PP sectional view.

[0031] Figure 9 This is a schematic diagram of the assembly structure of the drive shaft, hub, and bushing in this invention.

[0032] Figure 10 This is a schematic diagram of the hub structure in this invention.

[0033] Figure 11 This is a schematic diagram of the pressure plate in this invention.

[0034] Figure 12 This is a schematic diagram of the structure of the cover B in this invention.

[0035] Figure 13 This is a schematic diagram of the front view structure of a slipper clutch in the prior art.

[0036] Figure 14 for Figure 13 DD sectional view.

[0037] Explanation of reference numerals in the attached drawings: outer bushing 1', steel back 2', inner bushing 3', friction plate 4', front cover 5', spring A6', spring B7', grease nipple 8', flat washer 9', snap ring 10', bolt 11', inner bushing 12', outer bushing 13', locking washer 14', mounting bolt 15';

[0038] Cover A1, Cover B2, Friction Plate 3, Driven Disc 4, Pressure Plate 5, Disc Hub 6, Diaphragm Spring 7, Support Ring 8, Bearing A9, Disc Spring 10, Drive Shaft 11, Wave Washer 12, Bushing 13, Rivet A14, Rivet B15, Bearing B16, Spline Groove 17, Internal Gear 18, External Spline 19, Internal Spline 20, Groove 21. Detailed Implementation

[0039] The present invention will now be described in detail with reference to the accompanying drawings:

[0040] Example: As attached Figures 1-12 As shown, this enclosed, maintenance-free, torque-limiting slip clutch includes a housing A1, a housing B2, a friction plate 3, a driven disc 4, a pressure plate 5, a disc hub 6, a diaphragm spring 7, a support ring 8, a bearing A9, a disc spring 10, a drive shaft 11, a wave washer 12, a bushing 13, rivets A14 and B15, a bearing B16, a spline groove 17, internal teeth 18, external splines 19, internal splines 20, and a groove 21.

[0041] Reference Appendix Figure 1 , 2 A friction plate 3 is bonded to both the left and right surfaces of the driven disk 4. After the disk hub 6 is inserted into the inner hole of the driven disk 4, it is riveted to one side of the driven disk 4 by rivets A14 to form the first component.

[0042] like Figure 3 , 4 As shown, a disc spring 10 is placed in the inner hole of the cover A1, and then the bearing B16 is pressed into the inner hole of the cover A1 so that it abuts against the disc spring 10 to form the second component.

[0043] Reference Appendix Figure 5 , 6 A disc spring 10 is also placed in the inner hole of the cover B2, and then the bearing A9 is pressed into the inner hole of the cover B2 so that it abuts against the disc spring 10 to form the third component.

[0044] Furthermore, an annular groove 21 is formed on the inner wall of the casing B2 (as shown in the image). Figure 6 , 12 As shown), it is used to place the support ring 8. Figure 7 , 8 The housing A1 of the second component and the housing B2 of the third component are aligned and riveted together by rivets B15 to form a closed inner cavity. The drive shaft 11 passes through the housing A1 and housing B2 in sequence and is supported on bearings A9 and B16. The first component is placed in the inner cavity and is sleeved on the drive shaft 11 by the hub 6. A diaphragm spring 7 is provided between the support ring 8 and the pressure plate 5 to apply pressure to the pressure plate 5, so that the pressure plate 5 presses the friction plate 3 on one side of the driven plate 4, and the friction plate 3 on the other side of the driven plate 4 is pressed against the inner wall of the housing A1.

[0045] Preferably, the drive shaft 11 engages with the inner spline 20 of the hub 6 via the external spline 19. A disc spring 10 is inserted between the inner bore of the cover B2 and one end face of the bearing A9, pressing the bushing 13 between the other end face of the bearing A9 and the end face of the external spline 19; a disc spring 10 is inserted between the inner bore of the cover A1 and one end face of the bearing B16, and a wave washer 12 is inserted between the other end face of the bearing B16 and the end face of the external spline 19. The outer wall of the pressure plate 5 is provided with a spline groove 17, which can cooperate with the internal teeth 18 on the inner wall of the cover B2. The mounting surfaces of the cover A1 and the cover B2 are coated with sealant and sprayed with anti-rust paint to increase rust and corrosion resistance, improve sealing performance, and effectively extend the service life of the clutch.

[0046] Assembly process of the present invention:

[0047] During assembly, a support ring 8 is inserted into the groove 21, and the diaphragm spring 7 is placed on the support ring 8 with its small end facing down. Then, a bushing 13 is placed on the bearing A9 of the third assembly. The drive shaft 11 is passed through the inner hole of the bushing 13 and fitted onto the inner hole of the bearing A9, and pressed and fixed. Positioning the pressure plate 5 around the outer diameter of the bushing 13, the spline groove 17 on the outer diameter of the pressure plate 5 engages with the internal teeth 18 on the cover B2. Next, the first assembly is fitted onto the drive shaft 11, and the internal spline 20 of the hub 6 on the first assembly engages with the external spline 19 of the drive shaft 11. Finally, a wave washer 12 and the second assembly are fitted onto the drive shaft 11, and the cover A1 and cover B2 are riveted together with rivets B15 to form a sliding clutch assembly.

[0048] During operation, the sliding clutch is mounted on the pulley and secured with bolts. A diaphragm spring provides clamping force. The center diameter of the support ring and the radius R of the pressure plate serve as fulcrums. The pressure plate presses the friction plate assembly against housing A. The outer teeth of the pressure plate are connected to housing B via a spline fit. The inner teeth of the friction plate assembly's hub are connected to the drive shaft via a spline fit. Both ends of the drive shaft are secured with wave washers, bushings, and bearings respectively mounted on housing A and housing B. The wave washers are used to eliminate assembly gaps between components, and the bushings are used for center positioning of the pressure plate. Sealant is applied to the mounting surfaces of housing A and housing B, and they are riveted together. The gap between the bearings and the housing is eliminated using disc springs. The drive shaft is connected to a shaft via a key fit.

[0049] Working principle:

[0050] The pressure plate applies force through the diaphragm spring to the friction plate assembly (friction plate and driven plate). By calculating and selecting the appropriate diaphragm spring angle and thickness, an appropriate clamping force is generated. When the impact torque exceeds the set limit, it is greater than the force of the diaphragm spring, making it impossible for the diaphragm spring to press the friction plate assembly. The transmission of overload torque is limited by the sliding friction of the friction plate assembly.

[0051] Torque transmission route: Shaft 1 → Drive shaft → Hub → Friction plate → Pressure plate → Cover B → Pulley.

[0052] This invention primarily targets the Claas combine harvester, with a designed slippage torque of 900±100 N·m. Based on the product's slippage torque, comprehensive verification and calculations were performed to maximize reliability while ensuring product performance. Considering the combine harvester's operating conditions and environment, which demand extremely high corrosion resistance, a closed structural design was adopted. The surfaces of casings A and B are treated with anti-rust paint to enhance rust and corrosion resistance. A diaphragm spring structure was employed. Based on the design principles of clutch diaphragm springs, the clamping force remains minimally altered within the service life of the friction plates (wear ≤3mm), requiring virtually no adjustment or maintenance, thus improving product reliability and convenience.

[0053] It is understood that, for those skilled in the art, any equivalent substitutions or modifications to the technical solutions and inventive concepts of this invention should fall within the scope of protection of the appended claims.

Claims

1. A closed-maintenance-free torque-limited slip clutch characterized by: include Driven disk (4), a friction plate (3) is fixed on both sides of the driven disk (4), a hub (6) is installed in the inner hole of the driven disk (4), and the hub (6) is riveted to the driven disk (4) to form the first component; Cover A (1), bearing B (16) is pressed into the inner hole of cover A (1) to form a second component; Housing B(2), bearing A(9) is pressed into the inner hole of housing B(2) to form a third component; and A drive shaft (11) is fitted with a bushing (13), and a pressure plate (5) is fitted around the outer periphery of the bushing (13). The second component's housing A (1) and the third component's housing B (2) are aligned and riveted together to form a closed inner cavity. The drive shaft (11) passes through housing A (1) and housing B (2) in sequence and is supported on bearing A (9) and bearing B (16). The first component is placed into the inner cavity and fitted onto the drive shaft (11) through a hub (6). A support ring (8) is embedded in the inner wall of housing B (2). A diaphragm spring (7) is provided between the support ring (8) and the pressure plate (5) to apply pressure to the pressure plate (5), so that the pressure plate (5) presses the friction plate (3) on one side of the driven plate (4), and the friction plate (3) on the other side of the driven plate (4) is pressed against the inner wall of housing A (1). The drive shaft (11) engages with the inner spline (20) of the hub (6) via an external spline (19); A disc spring (10) is placed between the inner hole of the cover B (2) and one side end face of the bearing A (9), so that the bushing (13) is pressed between the other side end face of the bearing A (9) and the end face of the external spline (19).

2. The closed-maintenance, limited-torque, slip clutch of claim 1, wherein: A disc spring (10) is placed between the inner hole of the housing A (1) and one side end face of the bearing B (16), and a wave washer (12) is placed between the other side end face of the bearing B (16) and the end face of the external spline (19).

3. The closed-maintenance, limited-torque, slip clutch of claim 1, wherein: The outer wall of the pressure plate (5) is provided with a spline groove (17) for cooperating with the internal teeth (18) on the inner wall of the cover B (2).

4. The closed-maintenance, limited-torque slip clutch of claim 1, wherein: An annular groove (21) is provided on the inner wall of the cover B (2) for inserting the support ring (8).

5. The closed-type maintenance-free torque-limiting slip clutch according to claim 1, characterized in that: Sealant was applied to the mounting surfaces of the housing A (1) and housing B (2).

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