Clutch device having an intermediate lever and a path-based wear adjustment device which acts on said intermediate lever

Abstract

The invention relates to a clutch device (1) for an agricultural tractor, comprising a friction clutch (5) having a counter plate (2), a pressure plate (3) which can be axially moved relative to the counter plate (2), and a clutch disc (4) which can be frictionally pressed between the counter plate (2) and the pressure plate (3); and an actuating device (6) for axially moving the pressure plate (3), an actuating lever (7) of the actuating device (6) being pivotably mounted on a bearing device (8) fixed to the housing and being axially movably coupled to the pressure plate (3) indirectly via an actuating device (6) intermediate lever (9) which is pivotally mounted on the actuating lever (7). The radially inner end (10a) of the actuating lever (7) is coupled to an axially movable actuating ring (11), and the radially inner end (12a) of the intermediate lever (9) rests against a bearing surface (13) of an adjustable ramp device (14) while the radially outer end (12b) thereof is axially movably coupled to the pressure plate (3). The ramp device (14) is desgined to adjust the actuating lever (7) starting position, which can be changed due to a wear-induced movement of the pressure plate (3) relative to the counter plate (2), the ramp device (14) having a ramp ring (15) which defines the bearing surface (13) and which is driven by an automatic drive (16) controlled on the basis of wear.

Description

[0001] Coupling device with an intermediate lever and a wear adjustment device acting on it, based on the lever arm

[0002] The invention relates to a clutch device for an agricultural tractor, comprising a friction clutch with a counter plate, a pressure plate axially displaceable relative to the counter plate, and a clutch disc pressed between the counter plate and the pressure plate by frictional engagement. Furthermore, the clutch device has an actuating device for axially displacing the pressure plate, wherein an actuating lever of the actuating device is pivotably arranged on a housing-fixed bearing device and is indirectly coupled axially displaceably to the pressure plate via an intermediate lever of the actuating device which is in turn pivotably mounted on the actuating lever.The actuating lever is coupled at its radially inner end to an axially displaceable actuating ring, and the intermediate lever rests at its radially inner end against a bearing surface of an adjustable ramp device, while its radially outer end is axially displaceably coupled to the pressure plate. The ramp device (as part of a wear adjustment device) is designed to adjust the initial position of the lever, which changes as a result of wear-induced displacement of the pressure plate relative to the counter plate.

[0003] Basic coupling devices, also simply referred to as tractor couplings, are already well-known in the prior art. One such tractor coupling is disclosed, for example, in DE 10 2022 133 281 A1. The individual components of tractor couplings are usually designed to be so robust that, despite a certain amount of wear on the friction surfaces, the couplings could be operated throughout their entire service life. However, past developments and the lightweight construction measures implemented in this context, including reductions in installation space, have revealed that tractor couplings are often no longer sufficiently wear-resistant.

[0004] It is therefore an object of the present invention to enable a more efficient clutch actuation of a tractor clutch, which also makes clutches with a compact design usable over a long service life.

[0005] This is solved according to the invention by the fact that the ramp device has a ramp ring that defines the support surface and is driven by an automatic, wear-dependent controlled drive.

[0006] This design of the actuating mechanism allows the tractor clutch to be operated efficiently throughout its entire service life, despite its reduced dimensions. At the same time, it enables low-maintenance operation of the clutch system.

[0007] Further advantageous embodiments are claimed in the dependent claims and are explained in more detail below.

[0008] Accordingly, it is also advantageous if the drive has a preloading device designed such that it is brought into a preloaded state by the actuating ring during axial clutch actuation (preferably opening the friction clutch). This cleverly generates the drive energy required for subsequent readjustment from the axial adjustment that occurs anyway. The design can thus be further simplified.

[0009] In this regard, it is also advantageous if a locking device is provided which, in its locked state, blocks the drive of the ramp ring by the preloading device. Preferably, the locking device automatically assumes its locked state upon the preloading device reaching its preloaded state once. This allows the clutch to be actuated initially over a certain wear range / up to a certain wear limit without unnecessarily actuating the preloading device and the locking device.

[0010] Accordingly, it is also advantageous if the locking device, in the locking state, holds the pre-tensioning device in the pre-tensioned state.

[0011] If the locking device is designed in such a way that it maintains the locking state of the preloading device up to a certain wear limit of the contacting friction surfaces of the pressure plate, clutch disc and / or counter plate, normal operation can be carried out as efficiently as possible.

[0012] Furthermore, it is advantageous if the locking device is designed such that, upon exceeding a certain wear limit of the contacting friction surfaces of the pressure plate, clutch disc, and / or counter plate, it automatically assumes an unlocked state, thereby releasing a rotation of the ramp ring using the drive force / energy previously stored in the preloading device and thus readjusting the contact surface to the intermediate lever in the direction of the initial position. This ensures a simple final readjustment.

[0013] To ensure the least possible wear on the actuating device, it is advantageous if the radially inner end of the intermediate lever slides against the support surface designed as a ramp rising or falling in the circumferential direction.

[0014] Furthermore, the actuating mechanism is kept as simple as possible if the axial position of the radially inner end of the actuating lever is directly influenced by the position of the intermediate lever. This ensures that any wear-related adjustment / readjustment of the intermediate lever also directly results in a readjustment of the position of the side of the actuating lever contacting the actuating ring (the radially inner end). If the friction clutch is designed as a normally closed clutch, the actuating mechanism, including its wear adjustment, can be implemented as simply as possible.

[0015] Furthermore, it is advantageous to have two friction clutches and to have an actuating device designed for independent actuation of these two friction clutches. This allows for the efficient implementation of a compact dual clutch.

[0016] In other words, a self-acting, wear-dependent drive for a ramp ring is proposed. For this purpose, during axial clutch actuation (e.g., opening the clutch), the ramp ring drive is first pre-tensioned by, for example, tensioning a spring accumulator (pre-tensioning device) to an increased force / torque level. At the end of this axial movement, a lock (locking device) is activated to maintain the pre-tensioned state of the adjusting drive. This means that during a subsequent, opposing axial movement of the clutch actuation (e.g., closing the clutch), an adjustment (rotation of the ramp ring) does not necessarily have to occur immediately. An adjustment step should only occur when this lock is deactivated again. It follows that with several successive clutch actuations (e.g.,(Multiple opening of the clutch) without adjustment may only require a single tensioning of the spring accumulator.

[0017] The deactivation of the adjustment lock is designed to be wear-dependent, for example, depending on the height of the actuating lever tips / inner ends of the actuating levers, when the clutch is not engaged. If a certain height threshold is exceeded, the adjustment lock is automatically deactivated. In this situation (not engaged), the actuating levers are only subjected to a preload, but not to an actuating force. The contact forces on the adjustment ramp / ramp of the ramp ring are correspondingly low, so that the preload of the spring accumulator (force / torque level) is sufficient to perform one adjustment step. The energy for tensioning the spring accumulator is thus supplied by the actuating movement when the clutch is opened / engaged. Tensioning of the spring accumulator occurs with every clutch opening / engagement operation, regardless of the clutch's wear condition.

[0018] The clamping process (step 1) and the readjustment process (step 2) do not necessarily have to be carried out in a single operation to open / close the coupling.

[0019] The invention will now be explained in more detail below with reference to figures, in which context different embodiments are also illustrated.

[0020] They show:

[0021] Fig. 1 shows a schematic representation of a coupling device according to the invention in a preferred embodiment, in which in particular the structure of an actuating device of the coupling device can be seen and a closed position / a closed state of a friction clutch is implemented.

[0022] Fig. 2 shows a schematic representation of the coupling device similar to Fig. 1, wherein the actuating device in its actuated state has now moved the friction clutch into its open position / open state, while at the same time a preloading device of a wear adjustment device is preloaded.

[0023] Fig. 3 is a schematic representation of the coupling device similar to Fig. 1, illustrating that, following the state of Fig. 2, after the friction clutch has closed again, a locking device holds the preloading device in its preloaded state. Fig. 4 is a schematic representation of the coupling device similar to Fig. 1, wherein the friction clutch closes after a certain wear of the friction clutch components, so that the locking device releases the preloading device again and it can act on the ramp ring.

[0024] Fig. 5 shows a schematic representation of the coupling device similar to Fig. 1, wherein, compared to Fig. 4, the ramp ring has been adjusted.

[0025] Fig. 6 shows a schematic representation of the coupling device similar to Fig. 1 in the state after adjustment of the actuating device.

[0026] Fig. 7 shows a longitudinal section of the coupling device according to the invention according to Fig. 1, with a detailed illustration of the components of the coupling device, including an actuating ring (in its initial position) that adjusts several actuating levers of the actuating device.

[0027] Fig. 8 shows a longitudinal section view of the coupling device, similar to Fig. 7, with the friction coupling in its open state.

[0028] Fig. 9 shows a longitudinal section view of the coupling device after wear adjustment.

[0029] Fig. 10 shows a perspective view of a partial assembly of the coupling device, comprising a housing and several actuating levers of the actuating device pivotably mounted thereon.

[0030] Fig. 11 shows a perspective view of the assembly according to Fig. 10, additionally with an actuating ring that acts on the actuating levers to adjust them.

[0031] Fig. 12 shows a perspective view of the actuating ring alone,

[0032] Fig. 13 shows a perspective view of part of the actuating device on the housing in the area of ​​the ramp ring, as well as the drive ring that drives this ramp ring during operation. Figs. 14 and 15 show two top views of the coupling device in the area of ​​the ramp ring and the preloading device implemented in detail.

[0033] Fig. 16 shows a top view of the inserted ramp ring,

[0034] Fig. 17 shows a perspective view of one half of the ramp ring,

[0035] Fig. 18 shows a sectional view of the assembly of the coupling device of Fig. 11, in which a conical bolt on the actuating ring for driving the drive ring is clearly visible.

[0036] Fig. 19 shows a sectional view of the assembly of Fig. 11, similar to Fig. 17, in which the drive ring is now shifted / rotated in the circumferential direction by the conical bolt and at the same time the actuating device is actuated.

[0037] Figs. 20a and 20b show two perspective views of the coupling device in the area of ​​the cone bolt before (Fig. 20a) and after (Fig. 20b) pre-tensioning of the pre-tensioning device in the unactuated / closed state of the friction clutch.

[0038] Fig. 21 shows a perspective view of the entire coupling device of Fig. 7, as well as

[0039] Figs. 22a to 26b show different views of the coupling device in the area of ​​the pre-tensioning device and the locking device in the individual states before and after wear-related readjustment.

[0040] The figures are purely schematic and serve solely to illustrate the invention. The same elements are identified by the same reference numerals. Fig. 1 schematically depicts the coupling device 1 according to a preferred embodiment of the invention. The coupling device 1 is designed as a double coupling. Furthermore, the coupling device 1 is used as a tractor coupling, that is, as a coupling in a drive train of an agricultural tractor.

[0041] The coupling device 1 therefore has two friction clutches 5, of which only one friction clutch 5 is shown in Fig. 1 for the sake of clarity. In alternative embodiments, the coupling device 1 can also be implemented as a single clutch and thus contain only one friction clutch 5. The two friction clutches 5 can be actuated independently of each other.

[0042] An actuating device 6, which is also part of the coupling device 1, serves to actuate the friction clutch 5 shown in Fig. 1. For a more detailed description of the design and function of this actuating device 6, reference is made to DE 10 2022 133 281 A1, which is considered incorporated herein for this purpose. The basic design of the actuating device 6 thus corresponds to the actuating device of DE 10 2022 133 281 A1.

[0043] The actuating device 6 therefore serves to actuate the friction clutch 5, that is, to adjust the friction clutch 5 between a closed position and an open position, the closed position representing a normal / start position of the friction clutch 5. The friction clutch 5 is thus implemented as a normally closed friction clutch 5. The actuating device 6 is therefore arranged in its unactuated / inactivated state such that the friction clutch 5 is closed, and in its actuated / activated state such that the friction clutch 5 is open.

[0044] The actuating device 6 has a known design and includes an actuating lever 7, the radially inner / first end 10a of which is axially displaceable by a corresponding actuating bearing, here with an actuating ring 11 interposed. Furthermore, the actuating lever 7 is mounted at its radially outer / second end 10b in a housing-fixed bearing device 8 (pivotably). The actuating device 6 has several (approximately three) actuating levers 7, which are intended for actuating the friction clutch 5.

[0045] Radially between the first end 10a and the second end 10b, each actuating lever 7 is coupled in a displacement-resistant manner to an intermediate lever 9, preferably also via a bearing device 8 / pivot bearing.

[0046] The intermediate lever 9 rests with its radially outer / second end 12b directly against a coupling element 23 which is connected to a pressure plate 3 of the friction clutch 5 in a displacement-resistant manner. With its radially inner / first end 12a, the intermediate lever 9 rests against a support area, preferably further supported by the housing, in the form of a bearing surface 13 of a ramp ring 15. The ramp ring 15 and the previously mentioned actuating ring 11 are part of a wear adjustment device 24, which will be explained in more detail below.

[0047] The wear adjustment device 24 serves to adjust / recalibrate the contact surface 13 and thus indirectly also to adjust the area of ​​the actuating lever 7 in contact with the actuating ring 11 and thus the actuating bearing in the event of wear occurring during operation of the friction surfaces 19 of the pressure plate 3 and the (usually housing-fixed) counter plate 2, and in particular the clutch disc 4 arranged between them. The wear adjustment device 24 thus serves to adjust / axially adjust a contact area between the intermediate lever 9 and the contact surface 13 / the ramp ring 15 ( / a housing-fixed support point of the intermediate lever 9) at a specific wear path / a specific wear limit.

[0048] The ramp ring 15 forming a ramp device 14 of the wear adjustment device 24 can also be seen in the detailed illustrations of the coupling device 1 in Figs. 7 to 26b. The ramp ring 15 has a support surface 13 designed as a ramp for each intermediate lever 9 and thus for each contact area with an intermediate lever 9.

[0049] The ramps slope downwards in the circumferential direction with respect to the initial position shown in Fig. 1 (maximum height of the support surface 13). This is shown in a highly simplified manner in Fig. 1.

[0050] The ramp ring 15 is fixed to the housing, i.e., rotatably mounted on the housing 20, which can be seen, for example, in Fig. 10. The ramp ring 15 can be driven by a preloading device 17. The preloading device 17 is thus part of a drive 16 for driving / rotating the ramp ring 15.

[0051] The preloading device 17 has a preload spring 25 which, as can be seen below with reference to Figures 1 to 6, serves to temporarily store a preload force. Furthermore, the preloading device 17 has a drive ring 21 which in turn can be driven directly by the actuating ring 11. When the drive ring 21 rotates, it directly preloads the preload spring 25.

[0052] The (disc-shaped) actuating ring 11 has a contact surface / contact line that runs diagonally in the axial direction towards the drive ring 21. This contact slope 26 is formed, for example, by a conical bolt 22 and causes the drive ring 21 to rotate in a specific direction when the actuating ring 11 is moved / displaced axially (when the friction clutch 5 is actuated). The drive ring 21 and the preload spring 25 are matched to each other and, in turn, to the contact slope 26 of the actuating ring 11, such that axial movement of the actuating ring 11 during actuation of the friction clutch 5 causes the drive ring 21 to preload the preload spring 25.In the ultimately achieved pre-tensioned state of the pre-tensioning device 17, a locking device 18 stores the drive energy required for the subsequent wear adjustment by pre-tensioning the pre-tensioning spring 25.

[0053] The locking device 18 is preferably supported / mounted in a housing-fixed manner on one side and designed to provide positive-locking, rotationally fixed support for the drive ring 21 on the other. In its locked state, the locking device 18 thus directly blocks the drive ring 21. The locking device 18 can be unlocked by the actuating ring 11.

[0054] As can be seen in Figures 4 to 6, when a certain wear limit is reached of the friction surfaces 19 of the counter plate 2, pressure plate 3, and clutch disc 4, the actuating ring 11 is displaced by the changed lever height of the intermediate lever 9 and the actuating lever 7 by the actuating bearing (not shown for clarity) to such an extent that the locking device 18 automatically releases from its locked position and thus immediately releases the preloading device 17. It should be noted that the actuating ring 11, which is displaced by the actuating bearing when the clutch is disengaged / actuated, is conversely driven by the actuating levers 7 when the clutch is engaged / closed and, in its worn state, reaches an axial height to trigger the adjustment. The actuating bearing may, under certain circumstances, already lift off the actuating ring 11 in the axial direction; thus, it does not actuate in this case.

[0055] The preloading device 17 thus transfers the drive energy previously stored in the preload spring 25 directly to the drive ring 21, which in turn rotates the ramp ring 15 via a corresponding detent mechanism 27. This brings the preload spring 25 into its relaxed state, while simultaneously rotating the ramp ring 15 relative to the intermediate lever 9 and thus causing the radially inner end 12a of the intermediate lever 9 to slide along the ramped support surface 13. This ultimately returns the contact area between the intermediate lever 9 and the actuating lever 7 axially to its initial position.

[0056] Figures 7 to 26b then show several details of the preferred designs of the individual components.

[0057] In other words, Figures 1 to 3 show a scheme of the process during clutch actuation, with the tensioning of the spring accumulator (pre-tensioning device 17) and activation of the adjustment lock (locking device 18).

[0058] The schematic diagram initially shows an actuating lever 7 with an intermediate lever 9 and adjustment ramps. Furthermore, it shows a section with elements for tensioning the adjusting spring accumulator (pre-tensioning device 17) and one for locking / unlocking the adjustment based on wear (wear sensing).

[0059] An intermediate component (actuating ring 11) is mounted between the tips / ends of the actuating levers 7 and the actuating bearing (release bearing). The actuation of the levers (actuating levers 7) is effected indirectly via this intermediate component.

[0060] When the clutch (friction clutch 5) is actuated / opened, a ramp mechanism 28 acts during the axial disengagement movement and tensions a spring element or several springs (preload spring 25) to a higher force / torque level. With sufficiently large axial movement (minimum for disengaging the clutch), the locking device 18 activates and prevents the spring accumulator from immediately returning to its initial position when the clutch is subsequently closed. Thus, when the clutch is closed / unactuated, the spring accumulator initially remains in a tensioned position. Figures 3 to 6 illustrate a schematic of the sequence during an adjustment step: 1. Spring accumulator tensioned and adjustment lock activated (Fig. 3); 2. Adjustment lock is opened and the ramp ring 15 is moved (rotated) (Fig. 4); 3. The lever tip height is adjusted / reduced (Fig. 5); and 4. The spring accumulator relaxes.

[0061] In the closed / disengaged state of the clutch, the spring accumulator is pre-tensioned by the previous disengagement process, and if there is insufficient wear, the lock remains engaged. No adjustment step occurs. Only when further wear occurs does the height of the actuating lever 7 increase, and the lock is released. The pre-tensioned spring accumulator can now perform an adjustment step (rotation of the ramp ring 15). The range of motion for this adjustment is limited, for example, by a travel-limiting stop on the spring accumulator. The movement of the ramp ring 15 changes the contact height of the intermediate lever 9 on the ramp ring 15, and consequently, the height of the actuating lever 7 decreases. Thus, the change in lever height due to wear is at least partially or completely compensated.The axial height of the actuating ring 11 is reduced so that the locking device for the spring accumulator can be reactivated during a subsequent disengagement process.

[0062] Figures 7 and 8 show cross-sectional views of the coupling / coupling device 1 such that in Figure 7 the coupling is closed in the unactuated state and in Figure 8 it is open in the actuated state.

[0063] The arrangement and function of the actuating lever 7 (e.g. three arranged in a pattern on a coupling) with intermediate lever 9 and contact of the intermediate lever 9 to a ramp ring 15 mounted on the housing 20 is also recognizable here.

[0064] The wear adjustment preferably acts only on one friction clutch 5 (driving clutch) of the dual clutch. Therefore, only the relevant parts of the actuation of this clutch are mentioned in the following explanations. Figures 7 and 9 again show the clutch in cross-sectional view such that the clutch in Figure 7 is shown in its new condition (without wear) and in Figure 9 (also in the unactuated state (clutch closed)) in its worn condition, with the adjusted ramp ring 15.

[0065] It is evident that the wear condition can be compensated for by changing the contact height of the intermediate lever 9 on the ramp ring 15. The height of the actuating levers 7 remains largely unchanged. This also means that the axial height or working travel of the actuating ring 11 between the lever tips and the release / actuating bearing remains largely constant.

[0066] In Figs. 10 to 12 the arrangement of the actuating ring 11 can be clearly seen, with Fig. 10 showing the arrangement with the actuating levers 7 of the drive clutch and a second clutch (e.g. PTO), Fig. 11 showing this arrangement with the actuating ring 11 and Fig. 12 showing an exemplary embodiment of the actuating ring 11.

[0067] It can be seen that the actuating ring 11 rests on the tips of the actuating levers 7 for the self-adjusting clutch. The release / actuating bearing acts on the lever tips via the inner area of ​​the actuating ring 11.

[0068] When the clutch is engaged / disengaged, the actuating ring 11 is moved axially. With wear, the axial height of the actuating ring 11 changes accordingly when the clutch is engaged / disengaged.

[0069] To prevent axial separation / lifting of the actuating ring 11 from the tips of the actuating levers 7 when the clutch is closed / unactuated (the release bearing lifts off the actuating levers 7), preload springs exert an axial force on the actuating ring 11 and hold it against the lever tips.

[0070] Figures 13 to 17 clearly show the arrangement of the spring accumulator for the ramp ring drive. The arrangement of a ramp ring 15, for example, mounted in the housing 20, is visible. The ramp ring 15 has a toothed section 29 (the detent mechanism 27) and can thus be driven stepwise, for example, by a drive spring 30, to perform the adjustment movements. For this purpose, the drive spring 30, which is fixed to the drive ring 21, must be moved stepwise in the circumferential direction.

[0071] During circumferential movement against the adjustment direction, the radially elastic part (arm) of the drive spring 30 initially skips one tooth of the gearing 29 / ramp ring gearing. For each adjustment step, the drive spring 30 then advances the ramp ring 15 by one tooth width in the direction of adjustment.

[0072] The drive (force / torque) for this adjustment step is to be provided by the spring accumulator. For this purpose, several spring elements (preload springs 25 (here designed as torsion springs, acting between the housing 20 and the drive ring 21, which is mounted, for example, on the housing 20) preferably act between the housing 20 and the drive ring 21 and are mounted, for example, on housing-fixed bolts 31). The force / torque level of the spring accumulator should preferably be dimensioned such that it is sufficient for the complete execution of a full adjustment step. The extent of each adjustment step is limited by an end stop acting on the drive ring 21 and / or the drive spring 30.

[0073] The tensioning of the spring accumulator to a force / torque level required for readjustment is to be achieved by the axial movement of the actuating ring 11 when the clutch is disengaged / opened.

[0074] Figures 18 and 19 again show cross-sections of the clutch, which illustrate the operation of the arrangement for tensioning the spring accumulator, with Figure 18 showing the situation with the clutch unactuated / closed and Figure 19 showing the situation with the clutch actuated / open.

[0075] The upper actuating ring is axially displaceable on several guide elements, e.g., guide pins 32 (directly realized by bolts 31), and can thus follow the movements during clutch actuation, while being supported in the direction of rotation (rotational test). The drive ring 21 is axially fixed (not vertically displaceable) in the housing 20, but rotatably mounted (e.g., in recesses / rotation contours of the lever bearing blocks). A ramp arrangement (ramp mechanism 28) acts between the actuating ring and the drive ring 21. For this purpose, conical bolts 22 are fixed to the actuating ring, and ramp sections 33 are formed on the drive ring 21 (e.g., arranged three times; other ramp configurations are also possible). During the axial disengagement movement to open the clutch, the ramp contacts act in such a way that the drive ring 21 is rotated. The rotation occurs against the force / torque of the spring accumulator, which is thus (further) tensioned.The force / energy required to tension the spring is thus derived from the release movement. This means that a slightly increased actuation / release force is required for the tensioning process.

[0076] List of reference signs

[0077] 1 coupling device

[0078] 2 Counter plate

[0079] 3 pressure plate

[0080] 4 clutch disc

[0081] 5 friction clutch

[0082] 6 Actuating device

[0083] 7 operating levers

[0084] 8 Storage device

[0085] 9 intermediate levers

[0086] 10a first end of the actuating lever

[0087] 10b second end of the actuating lever

[0088] 11 Actuating ring

[0089] 12a first end of the intermediate lever

[0090] 12b second end of the intermediate lever

[0091] 13 Contact surface

[0092] 14 Ramp device

[0093] 15 Ramp Ring

[0094] 16 Drive

[0095] 17 Pre-tensioning device

[0096] 18 Locking device

[0097] 19 friction surface

[0098] 20 cases

[0099] 21 Drive ring

[0100] 22 cone bolts

[0101] 23 coupling element

[0102] 24 Wear adjustment device

[0103] 25 Preload spring

[0104] 26 Contact angle

[0105] 27 Locking mechanism

[0106] 28 Ramp mechanism

[0107] 29 Gearing

[0108] 30 Drive spring

[0109] 31 bolts

[0110] 32 guide pins

[0111] 33 Ramp area

Claims

Patent claims 1. Coupling device (1) for an agricultural tractor, comprising a counter plate (2), a pressure plate (3) axially displaceable relative to the counter plate (2), and a clutch disc (4) frictionally pressed between the counter plate (2) and the pressure plate (3), an actuating device (6) for axially displacing the pressure plate (3), wherein an actuating lever (7) of the actuating device (6) is pivotably arranged on a housing-fixed bearing device (8) and is indirectly axially displaceably coupled to the pressure plate (3) via an intermediate lever (9) of the actuating device (6) pivotably mounted on the actuating lever (7).wherein the actuating lever (7) is coupled at its radially inner end (10a) to an axially displaceable actuating ring (11) and the intermediate lever (9) bears at its radially inner end (12a) against a support surface (13) of an adjustable ramp device (14), while its radially outer end (12b) is axially displaceably coupled to the pressure plate (3), wherein the ramp device (14) is designed to readjust an initial position of the actuating lever (7) which may change as a result of wear-related displacement of the pressure plate (3) relative to the counter plate (2), characterized in that the ramp device (14) has a ramp ring (15) that defines the support surface (13) and is driven by an automatic, wear-dependent controlled drive (16).

2. Coupling device (1 ) according to claim 1 , characterized in that the drive (16) has a preloading device (17) which is designed such that it is brought into a preloaded state during axial clutch actuation by the actuating ring (11 ).

3. Coupling device (1) according to claim 1 or 2, characterized in that a locking device (18) is further provided which is designed such that that in its locked state it blocks the driving of the ramp ring (15) by means of the pretensioning device (17).

4. Coupling device (1 ) according to claim 3, characterized in that the locking device (18) in the locked state holds the preloading device (17) in the preloaded state.

5. Coupling device (1 ) according to claim 3 or 4, characterized in that the locking device (18) is designed such that it maintains the locking state of the preloading device (17) up to a certain wear limit of the friction surfaces (19) in contact of the pressure plate (3), clutch disc (4) and / or counter plate (2).

6. Coupling device (1) according to claims 3 to 5, characterized in that the locking device (18) is designed such that, when a certain wear limit of the contacting friction surfaces (19) of the pressure plate (3), clutch disc (4) and / or counter plate (2) is exceeded, it automatically assumes an unlocked state, releasing a rotation of the ramp ring (15) by means of the drive force previously stored in the preloading device (17) and thus adjusting the contact surface (13) to the intermediate lever (9) in the direction of the initial position.

7. Coupling device (1 ) according to one of claims 1 to 6, characterized in that the radially inner end (12a) of the intermediate lever (9) slides against the support surface (13) designed as a ramp rising or falling in the circumferential direction.

8. Coupling device (1 ) according to one of claims 1 to 7, characterized in that an axial position of the radially inner end (10a) of the actuating lever (7) is directly influenced by the position of the intermediate lever (9).

9. Coupling device (1 ) according to one of claims 1 to 8, characterized in that the friction coupling (5) is designed as a normally closed coupling.

10. Coupling device (1 ) according to one of claims 1 to 9, characterized in that two friction clutches (5) are provided and the actuating device (6) is designed for independent actuating of both friction clutches (5).

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