Clutch device for coupling a first shaft to a second shaft in a vehicle, dual clutch system for a tractor comprising a clutch device, and drivetrain comprising a clutch device

Abstract

The invention relates to a clutch device (1) for coupling a first shaft to a second shaft in a vehicle, the clutch device comprising at least one clutch disc, at least one pressure plate (2), and at least one diaphragm spring (3), wherein the diaphragm spring (3) is designed to press the pressure plate (2) against the at least one clutch disc such that the first shaft is coupled to the second shaft, wherein the pressure plate (2) comprises at least six fixing elements (4) which are arranged radially around a circumference of the pressure plate (2), wherein the diaphragm spring (3) comprises at least six recesses (5) which are distributed around a circumference of the diaphragm spring (3) at its inner diameter, wherein the at least six fixing elements (4) are designed to be positioned in the six recesses (5) in such a way that the diaphragm spring (3) is secured against rotation and centred with respect to the pressure plate (2). The invention also relates to a clutch system comprising such a clutch device and to a drivetrain comprising such a clutch device.

Description

[0001] Coupling device for coupling a first shaft to a second shaft in a vehicle, dual clutch system for a tractor with a coupling device, drive train with a coupling device

[0002] The invention relates to a coupling device for coupling a first shaft with a second shaft in a vehicle, comprising at least one clutch disc, at least one pressure plate and at least one disc spring, wherein the disc spring is arranged to press the pressure plate against the at least one clutch disc so that the first shaft is coupled to the second shaft, a dual clutch system for a tractor with a coupling device and a drive train with such a coupling device.

[0003] Coupling devices for vehicles are generally known from the prior art. These devices serve to couple, for example, a first shaft connected to an engine and a second shaft that serves as the input shaft for a transmission. The coupling device comprises, in particular, a pressure plate that is pressed against a clutch disc by means of a disc spring to couple the shafts. The disc spring must be secured against rotation and simultaneously centered in the circumferential direction to enable optimal power transmission and reduce wear. Manufacturing the pressure plate is complex, as it requires, among other things, centering pins and corresponding bores for centering and anti-rotation purposes.

[0004] In this context, it has now become apparent that there is a need to provide a coupling device for coupling a first shaft and a second shaft in a vehicle, in particular a need to provide an improved coupling device for coupling a first shaft and a second shaft in a vehicle.

[0005] It is therefore an object of the present invention to eliminate, or at least partially eliminate, the disadvantages described above in coupling devices for connecting a first shaft and a second shaft in a vehicle. In particular, it is an object of the present invention to provide an improved coupling device for connecting a first shaft and a second shaft in a vehicle.

[0006] This problem is solved in a coupling device of the generic type according to the invention by the fact that the pressure plate has at least six fixing elements which are arranged radially over a circumference of the pressure plate; wherein the disc spring has at least six recesses which are arranged distributed over a circumference of the disc spring on its inner diameter, wherein the at least six fixing elements are arranged in such a way as to be arranged in the six recesses in such a way as to prevent rotation and to center the disc spring in the circumferential direction relative to the pressure plate.

[0007] Furthermore, the problem is solved by a dual clutch system for a tractor with the features of independent claim 9 and by a drive train with the features of independent claim 10.

[0008] Features disclosed in connection with the clutch device according to the invention naturally also apply in connection with the dual clutch system according to the invention, the drive train according to the invention and vice versa, so that with regard to the disclosure of the individual aspects of the invention, mutual reference is always made or can be made.

[0009] According to a first aspect of the present invention, a coupling device for coupling a first shaft with a second shaft in a vehicle is provided, comprising at least one clutch disc, at least one pressure plate, and at least one disc spring, wherein the disc spring is configured to press the pressure plate against the at least one clutch disc so that the first shaft is coupled to the second shaft, characterized in that the pressure plate has at least six fixing elements arranged around a circumference of the pressure plate; wherein the disc spring has at least six recesses distributed around a circumference of the disc spring on its inner diameter, wherein the at least six fixing elements are configured to be arranged in the six recesses such that anti-rotation and centering in the circumferential direction of the disc spring relative to the pressure plate is achieved.

[0010] The term "coupling" in this context refers specifically to connecting a first shaft to a second shaft for torque transmission. The first shaft, in this context, refers specifically to an output shaft connected to a motor, for example, an internal combustion engine. The second shaft, in this context, refers specifically to an input shaft for a transmission or an output shaft or power take-off shaft for a driven machine.

[0011] In this context, the term "vehicle" refers specifically to a motor vehicle. This can be, in particular, one of the following: passenger car, commercial vehicle, tractor.

[0012] The term "clutch disc" in this context refers to a disc designed to be pressed against a flywheel or a rotating housing to couple a first shaft to a second shaft. The necessary clamping force can preferably be provided by a disc spring, which presses a pressure plate against the clutch disc. The disc spring can, for example, be supported by a housing. A release mechanism can counteract the clamping force exerted by the disc spring, thus disengaging the connection. For this purpose, lever mechanisms can be used, for example, to press the pressure plate against the force of the disc spring.

[0013] The term pressure plate, as used here, refers to a structural disc designed to apply a force to the clutch disc for coupling a first shaft to a second shaft. The pressure plate may comprise a casting. The pressure plate may be produced from the casting by machining. The term disc spring, as used here, refers in particular to an annular disc with an inwardly curved or conical geometry that provides a spring force when preloaded. The disc spring may have recesses on its inner radius. These recesses may be evenly distributed around the circumference. The areas between the recesses are referred to as spring tongues. The disc spring may preferably bear its outer region against a housing of the coupling device or against a second pressure plate. The disc spring may bear its inner region against the pressure plate.

[0014] In this context, the term recess refers in particular to a radially inwardly directed free space on the disc spring, which is designed to encompass a fixing element.

[0015] The term "centering" here refers to the circumferential alignment of the disc spring. This circumferential alignment ensures optimal force transmission from the disc spring to the pressure plate. The pressure plate may, for example, have internal cams against which the disc spring radially centers and / or is supported. The disc spring may have so-called spring tongues between the recesses, which face these internal cams. Ideally, the spring tongues are positioned directly opposite the internal cams.

[0016] In this context, the term "fixing element" refers in particular to a structural area that projects axially from the pressure plate and is designed to engage in a recess of the disc spring when assembled. The fixing element may be an integral part of the pressure plate. The fixing element may have an outer contour that corresponds to an inner contour of a recess in the disc spring. When the pressure plate and disc spring are assembled, the inner contour of the disc spring and the outer contour may partially touch. The inner contour of the recess in the disc spring and the outer contour of the fixing element may be designed to provide a clearance fit. This clearance may be circumferential and / or radial. The clearance may, for example, be in the range of 0.5 mm to 1.5 mm, preferably in the range of 1 mm.The fixing elements are preferably distributed evenly around the circumference of the pressure plate.

[0017] The invention is based on the understanding that three centrifugal pins are typically used to center the disc spring circumferentially. To improve the contact between the pressure plate and the disc spring, a wire ring is additionally used, which is arranged on the inside of the pressure plate. In this case, the centrifugal pins collide with the wire ring. This results in the following conflict: the bearing diameter of the wire ring is determined by the force transmission from the disc spring to the pressure plate. However, the centering pins should also be arranged close to this diameter in order to minimize the relative movement with respect to the slots in the disc spring that the centering pins engage. Therefore, the wire ring and several centering pins would have to be arranged at approximately the same diameter, which is practically impossible to achieve with a continuous wire ring.The previous solution involved using only a centering pin and an open wire ring, i.e., a wire ring that did not completely encircle the spring. However, this only prevents the disc spring from rotating circumferentially and does not center it. A known problem in practice is that this centering pin can loosen due to vibrations in the tractor and slip out of the bore in the pressure plate. The consequence is that the disc spring can then twist, leading, among other things, to increased wear and less favorable power transmission characteristics.

[0018] The invention proposes a new form of anti-rotation device for the disc spring, using six special cams as fixing elements on the pressure plate instead of the usual centering pins. These areas are pre-cast on the raw casting and machined for the finished part, precisely matching the recesses of the disc spring geometrically. This secures the disc spring against rotation in the circumferential direction. The new design of the fixing areas thus provides not only anti-rotation but also circumferential centering.

[0019] This method advantageously eliminates the need for centering pins, simplifying the manufacturing of the pressure plate. Furthermore, a wire ring can be used to simultaneously achieve circumferential centering, optimizing power transmission and reducing wear.

[0020] According to a preferred embodiment, the fixing element can protrude into the recess of the disc spring in a mounted state.

[0021] Such a vertical design of the geometry of the fixing elements allows for a stop or positive locking mechanism, thus preventing rotation. Furthermore, it enables centering.

[0022] According to a preferred embodiment, the fixing element can be arranged to at least partially touch an inside of the recess in a circumferential and / or radial direction when the disc spring and the pressure plate are mounted, thus achieving anti-rotation and centering of the disc spring.

[0023] Such a geometric design allows for a proper fit. This fit can preferably be a clearance fit with a clearance of 0.5 mm to 1.5 mm. This enables centering as well as preventing rotation.

[0024] After machining, the lower sections of the fixing elements are shaped so that their contours can advantageously engage with the recesses, thus creating a functional centering of the disc spring relative to the pressure plate. The contact areas on the inner diameter are advantageously larger compared to previous designs, thereby preventing, or at least reducing, any potential relative movement of the disc spring. This results in less wear and reduced force hysteresis.

[0025] According to a preferred embodiment, a coupling device may further comprise a wire ring to improve contact between the disc spring and the pressure plate; wherein the pressure plate has a circumferential groove for arranging the wire ring; wherein the wire ring is arranged in the circumferential groove.

[0026] The groove can be machined by processes such as milling or turning. The wire ring effectively improves force transmission between the spring plate and the pressure plate. Combined with the six fixing elements, this results in better overall force transmission, anti-rotation protection, centering, and simplified manufacturing. The groove can be continuous or partially circumferential. The wire ring can be continuous or open. An open wire ring allows for more cost-effective production.

[0027] According to a preferred embodiment, the wire ring can be closed.

[0028] In this way, optimal power transmission can be achieved.

[0029] According to a preferred embodiment, the at least six fixing elements can be arranged radially offset to the outside of the circumferential groove.

[0030] This allows the use of a wire ring, thus improving power transmission. Furthermore, it enables easier machining.

[0031] According to a preferred embodiment, the pressure plate can have six fixing elements and the disc spring can have six corresponding recesses for the fixing elements.

[0032] Investigations have shown that optimal centering and anti-rotation protection can be achieved with six fixing elements and six corresponding recesses. This eliminates the need for additional fixing elements, which has a positive impact on manufacturing costs.

[0033] According to a preferred embodiment, the pressure plate can be a casting. The casting can be machined.

[0034] According to another aspect of the present invention, a dual clutch system for a tractor is provided with a clutch device described in more detail above.

[0035] According to another aspect of the present invention, a drive train is provided with a coupling device described in more detail above.

[0036] In this context, the term drivetrain refers to an assembly designed to transmit the power of an engine to the wheels.

[0037] The invention is explained below with the aid of a drawing. The drawing shows:

[0038] Figure 1 shows a coupling device according to the invention,

[0039] Figure 2 shows a partial view of a coupling device according to the invention.

[0040] Figure 3 shows a sectional view of a coupling device according to the invention.

[0041] Figure 4 shows another sectional view of a coupling device according to the invention, and

[0042] Figure 5 shows another view of a pressure plate according to the invention.

[0043] The figures are schematic and serve only to illustrate the invention. The same elements are identified by the same reference numerals. Figure 1 shows a coupling device 1 according to the invention for coupling a first shaft (not shown) with a second shaft (not shown) in a vehicle (not shown). The coupling device 1 comprises a pressure plate 2. The pressure plate 2 has bores 10 for connection to levers of a release device. A clutch disc (not shown) is arranged between the flywheel and the pressure plate 2. The coupling device 1 further comprises a disc spring 3, which is configured to press the pressure plate 2 against the clutch disc to enable coupling of the first shaft with the second shaft. A release device (not shown) can, for example, press the pressure plate 2 against the disc spring 3 to disengage the clutch.The disc spring 3 is supported, for example, by a housing (not shown). The pressure plate 2 has six fixing elements 4, which are evenly distributed around its circumference.

[0044] The disc spring 3 has six corresponding recesses 5 in which the six fixing elements 4 are arranged to achieve centering and alignment in the circumferential direction and to prevent rotation. Furthermore, the coupling device 1 has a wire ring 7 which is arranged in a groove 8. The fixing elements 4 are arranged radially outwards towards the groove 8 and the wire ring 7 located therein. Cams 9 and 14 are also arranged on the inner area of ​​the pressure plate 2. The inner cams 14 are located opposite the projecting areas (also called spring tongues) of the disc spring 3, which adjoin further recesses 15 of the disc spring 3. The inner cams 14 serve to center the disc spring 3 in the radial direction.

[0045] The inner cams 9 also extend to the areas opposite the fixing elements 4. The inner cams 9 are simply wider than the inner cams 14, which provides additional stability. Ventilation windows 17 are arranged between the cams 9 and 14.

[0046] Figure 2 shows a partial view of a coupling device 1 according to the invention. It can be seen that the wire ring 7 has an opening 11. Alternatively, the wire ring 7 can be closed. Furthermore, it can be seen that the contour 13 of the recess 5 is adapted to the contour 12 of the fixing element 4, so that there is a fit or only a small gap between the contours.

[0047] Figure 3 shows a sectional view of a coupling device 1 according to the invention. It can be seen that the wire ring 7 is arranged in the circumferential groove 8. Furthermore, the disc spring 3 rests on the wire ring 7.

[0048] Figure 4 shows a sectional view of a coupling device 1 according to the invention. It can be seen that in the area of ​​the fixing element 4 where the disc spring 3 does not rest on the wire ring 7, the groove 8 has a higher wall on its outer side for improved positioning of the wire ring 7. The higher wall is formed by the fixing element 4. This has a positive effect on the support of the wire ring 7. This area can preferably correspond to the area opposite the fixing element 4. In these areas, radial inner and very good radial outer support of the wire ring 7 is also provided.

[0049] Figure 5 shows another view of a pressure plate 2 according to the invention. Here it can be clearly seen that the groove 8 is interrupted by respective ventilation windows 17.

[0050] Reference symbol list

[0051] Coupling device

[0052] pressure plate

[0053] Disc spring

[0054] Fixing element

[0055] recess

[0056] Inside recess

[0057] Wire ring around running groove

[0058] cam

[0059] Drilling

[0060] Opening wire ring

[0061] Contour recess

[0062] Contour fixing element

[0063] Cam further recess

[0064] spring tongue

[0065] ventilation window

Claims

Claims 1. Coupling device (1) for coupling a first shaft with a second shaft in a vehicle, comprising at least one clutch disc, at least one pressure plate (2) and at least one disc spring (3), wherein the disc spring (3) is arranged to press the pressure plate (2) against the at least one clutch disc so that the first shaft is coupled to the second shaft, characterized in that the pressure plate (2) has at least six fixing elements (4) arranged radially around a circumference of the pressure plate (2); wherein the disc spring (3) has at least six recesses (5) distributed around its inner diameter around a circumference of the disc spring (3), wherein the at least six fixing elements (4) are arranged in the six recesses (5) such that anti-rotation and centering in the circumferential direction of the disc spring (3) relative to the pressure plate (2) is achieved.

2. Coupling device (1 ) according to claim 1 , characterized in that the fixing element (4) projects into the recess of the disc spring (3) in a mounted state.

3. Coupling device (1 ) according to claim 1 or 2, characterized in that the fixing element (4) is arranged to contact, at least partially in a circumferential and / or radial direction, an inner surface (6) of the recess (5) in a mounted state of the disc spring (3) and the pressure plate (2), so that anti-rotation protection and centering of the disc spring (3) is achieved.

4. Coupling device (1) according to one of the preceding claims, characterized in that The coupling device (1) further comprises a wire ring (7) to improve contact between the disc spring (3) and the pressure plate (2); wherein the pressure plate (2) has a circumferential groove (8) for arranging the wire ring (7); wherein the wire ring is arranged in the circumferential groove.

5. Coupling device (1 ) according to claim 4, characterized in that the wire ring (7) is closed.

6. Coupling device according to claim 4 or 5, characterized in that the at least six fixing elements (4) are arranged radially outwards offset to the circumferential groove (8).

7. Coupling device (1) according to one of the preceding claims, characterized in that the pressure plate (2) has six fixing elements (4) and the disc spring (3) has six recesses (5).

8. Coupling device (1) according to one of the preceding claims, characterized in that the pressure plate (2) is a cast part.

9. Dual clutch system for a tractor with a clutch device (1 ) according to claims 1 to 8.

10. Drive train with a coupling device (1) according to any one of claims 1 to 8.

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