BE1014007A3 - CLUTCH, CONNECTING ELEMENT AND DEVICE FORMED THEREFROM AND METHOD FOR ASSEMBLING A CLUTCH. - Google Patents

Abstract

In the case of a clutch with at least two discs of

Description

"Clutch, connection element and device formed therefrom and method of assembling a clutch” The invention relates to a clutch, a connection element of a clutch release unit and a device consisting of a clutch declutching unit and a corresponding connection element as well as a method of assembling a clutch.

The invention relates to clutches, used or intended to be used especially in combination with composite gearboxes in particular in the automotive sector. Such gearboxes are currently being tested for use in the automotive sector, since conventional gearboxes can no longer meet the increasing requirements associated with emission requirements. To be able to offer a gearbox serving as an alternative to automatic gearboxes or progressive gearboxes, we are working on automating a manual gearbox. It is therefore proposed to operate a gear shift by means of two drive shafts each provided with drive gears, which can mesh with corresponding drive gears of a driven shaft. One of the drive shafts must then carry the even ratios, and the other drive shaft, the odd ratios. With such gearboxes, it is possible to engage an even number ratio and an odd number ratio, while the corresponding clutch process is done by clutching and disengaging the relevant drive shaft. A gearbox of this kind essentially corresponds, in terms of shifting, to a manual gearbox, but it is more economical and has a higher efficiency and a higher number of reports than automatic gearboxes. Furthermore, such a gearbox also engages even under load and therefore does not have to be uncoupled completely, and therefore does not need as much synchronization as necessary with conventional gearboxes.

To make such a device, two clutches are therefore required. These however require a relatively large size and are relatively expensive.

The invention therefore aims to provide a device which can effectively and appropriately associate such a gearbox with a drive device, and which nevertheless has only the smallest possible footprint.

As a solution, a clutch is proposed with at least two friction discs, two corresponding coupling faces and two associated pressure plates, which can be actuated individually. On the one hand, such a device requires relatively little space, because only a clutch is used and in particular also a single clutch housing. In particular, only one clutch drive element must be connected to a motor or similar device. In addition, the device nevertheless ensures that the clutch operation and the mutual clutch and disengagement can be adapted adequately to existing situations.

The two coupling faces are preferably provided on at least one module, rigidly secured to a clutch housing. This may especially be the common clutch plate already described. On the one hand, such a rigid connection can be manufactured inexpensively. On the other hand, the individually actuable pressure plates allow, as before, individual clutch and disengage operations.

It is in particular possible to group the two coupling faces on a clutch plate. This ensures, on the one hand, a reduction in manufacturing costs and, on the other, a further reduction in size, since only a clutch plate has to be provided. The clutch plate is preferably arranged in the center between the two pressure plates. This results in another reduction in the size, so that such a clutch requires a size which is only very slightly greater than that of a simple clutch.

The construction of the clutch of the invention is particularly compact if a clutch housing envelops the two friction discs and the two pressure plates and, optionally, the clutch plate.

The housing may have radial openings to counter an accumulation of heat caused by the two friction discs.

The housing can be designed in such a way that it compensates for the control forces of two control springs associated respectively with a pressure plate. This can then be done particularly simply if the casing envelops the rest of the clutch. Thus, the compensation can be done through a device for holding the control springs or other spring elements and one or more other modules, rigidly secured to the clutch housing.

Preferably, one of the two pressure plates is pressed in the unloaded state against the corresponding coupling face (normally closed NC). In this context, the expression "unloaded state" describes a situation in which the clutch is not actuated. With such a device, it is ensured that the corresponding shaft is engaged, even in the event of an operational failure.

The pressure plate can in particular be applied against the friction disc by means of a spring washer. In this way, this part of the device of this clutch can be made as a single-plate clutch.

In addition, the second of the two pressure plates can freely rotate the friction disc corresponding to the unloaded state (normally open NO). In this way, even in the event of a breakdown, it is ensured that this shaft is uncoupled. This offers the advantage, in particular in combination with a first NC pressure plate, that no competing relationship is engaged.

Advantageously, both the first gear and the reverse gear interact with the pressure plate NC, so that in the event of a breakdown, at least the first gear or the reverse gear can be engaged. It goes without saying that such a clutch structure consisting of a clutch NC and a clutch NO is also advantageous independently of the other characteristics of the clutch.

The friction discs are preferably connected to output shafts arranged concentrically leading in turn to a corresponding gearbox. This allows a very compact structure of the entire device consisting of the clutch and the gearbox. In addition, the clutch can also be extremely compact, since then the friction discs themselves are arranged coaxially.

At least one of the friction discs can be designed so that it can oscillate easily. This makes it possible to compensate for alignment errors which can occur in particular due to the coaxial output shafts. In addition, such a device is suitable, here again independently of the other characteristics of the clutch, for economic compensation for such errors.

In particular, it is possible to produce the friction disc with elasticity in the radial direction. This can be ensured, for example, by suitable recesses which are provided in an area of the friction disc which fixes the friction lining to the corresponding shaft in the direction of rotation. Thus, we can do without autonomous spring elements. On the contrary, the term "rigid" means, in the present context, a positive engagement connection in the peripheral direction between the shaft and the friction lining, which is however capable of oscillating.

In addition, the friction disc may have axially directed zones, in particular in its zone connecting the friction lining to the corresponding shaft, which allow such oscillation. Thanks to such axially directed zones, the size can be better exploited, so that the clutch can be smaller.

Preferably, the lining of the first of the two friction discs is soft, and the lining of the second of the two friction discs is hard. In this case, the friction lining can be connected to a shaft for first gear and / or reverse. The soft friction disc ensures that the clutch guarantees a pleasant start. On the other hand, the hard friction disc should not meet this requirement, since it is only used for higher ratios. This device is advantageous, in particular in the sense that a hard friction disc has a significantly more compact construction.

In the present context, the expression "soft friction disc" describes a friction disc which satisfies all the requirements imposed on a clutch during starting. A "hard friction disc", on the other hand, is only a little harder than these requirements allow. In particular, a rigid sintered lining can be chosen as the hard friction disc, while a soft friction disc for vehicles is used as the soft friction disc. For the latter, packing springs can also be used.

To actuate the pressure plates, one can provide at least one control spring which has, both internally and externally, a lever arm. This means that a point of rotation following the exercise of centrifugal forces is moved radially inward and that the lever arms are exposed to moments of rotation in mutual opposition caused by centrifugal forces. One can also provide on the lever arm located externally, which will normally be the shortest, an additional mass which amplifies such compensation for centrifugal forces. Such a device can also be used independently of the other characteristics of the clutch for normal or simple clutch.

It is also possible, and in particular in combination with axial zones of the friction discs, which allow a reduction in space, to arrange the control springs almost radially, so that the influence of the force centrifugal is still largely reduced to a minimum.

The clutch can also have a clutch unit with two clutch release clutch stops, which can be actuated separately and each interact with one of the two pressure plates. The use of such a declutching unit allows a construction of the clutch of the invention with a relatively small footprint, despite the fact that the pressure plates are actuable individually.

At least one of the disengaging clutch releases is actuated preferably hydraulically. This allows on the one hand a relatively simple transmission of forces, and on the other, to be able to apply significant forces despite a relatively small footprint.

Preferably, at least one of the disengaging clutch releases is operationally associated with an electric actuator. This can also be done, for example, via a hydraulic device serving as a transmission element and force multiplication. The use of an electric actuator allows without any problem a actuation of the clutch controlled by computer, so that the clutch operations and uncoupling of an odd ratio and the clutch of an even ratio or conversely can be adjusted optimally.

Preferably, a first clutch release bearing is arranged radially outside the second clutch release bearing. This guarantees a compact construction and also allows a structure with radial symmetry, so that an angle-dependent mounting is not necessary.

The declutching unit is preferably also arranged coaxially with at least one of the output shafts, so that the construction of the entire device is symmetrical in revolution and compact. Such a device is therefore extremely reliable and simple to mount, since it is not necessary to center the declutching unit relative to the other modules.

The declutching unit is preferably configured in such a way that in the operating situation, the declutching declutching stops are contacted by opposing forces. Thus, by an appropriate choice of the corresponding spring elements or by additional compensation means, a large compensation can take place. It follows that not only is the clutch itself practically without force, but that the declutching unit is also practically without force when actuated. This allows load shedding of the gears and / or the crankshaft of an engine.

At least one clutch release bearing may be operationally associated with a control spring designed so that in the non-stressed state by a holding force, preferably a holding force of a hydraulic control for the clutch release bearing , it acts against the clutch release bearing. Thus, the entire device can be produced practically without play. On the other hand, it is also possible to provide instead of additional spring elements, which intervene directly on the clutch release bearing.

A control element may be provided between a first of the two control springs, preferably between an external lever arm of the control springs, and a first of the two pressure plates. This allows the actuation forces to be transmitted over a greater distance, so that, despite the use of a declutching unit with two clutch declutching stops, the pressure plate can be provided axially at another place. This ensures a simple structure during construction, which simplifies the entire assembly. This then results in a reduction in costs as a result.

In addition, such a device ensures that the declutching unit is accessible from one side and that the two pressure plates can be actuated without problem. The control element is preferably located radially outside the friction discs.

The control element may comprise at least one release finger preferably arranged axially between the control spring and the pressure plate. This allows the corresponding actuation forces to be transmitted relatively easily.

The control element may in particular have several disengaging fingers connected together by a retaining ring. This retaining ring thus makes it possible to assemble the entire declutching element in a working cycle, which leads to a corresponding reduction in costs.

To ensure better compensation for forces, tangential leaf springs known per se, arranged between the pressure plates and the casing for mounting the pressure plates with torsional resistance relative to the casing, can be designed so that 'they oppose a declutching effort. This means that this pressure plate must be disengaged with an amplified disengagement force, which is advantageous if a clutch of the other pressure plate is made with a force greater than that necessary for the disengagement of the first pressure plate. It goes without saying that such a tangential leaf spring, which exerts a force opposite to a disengaging force, can be advantageously used for the compensation of forces, also independently of the other characteristics of a clutch. This is particularly advantageous in combination with a control element, because this can generate an active declutching and therefore the tangential leaf spring should not be used for declutching as is the case in the state of the technical.

In addition, the declutching unit can be provided with a connector with symmetry of revolution with respect to an axis of rotation of the clutch. This connector may have at least one connecting element ensuring the connection of at least one clutch release bearing with an actuator.

With such a device, the assembly is clearly simplified, because the connector does not have to be assembled in a particular direction of rotation. On the contrary, it is possible to connect it without any problem to a corresponding connection element.

The invention therefore also provides a connection element for a clutch or for a clutch declutching unit, which has a recess with symmetry of revolution. Also in this recess, it is possible to provide at least one connecting element ensuring the connection of at least one declutching stopper to an actuator.

With such a device, it is in particular possible to already fix or connect the declutching unit to the rest of the clutch, and then proceed to assemble the entire device. It then suffices to engage the coupling of the declutching unit in the corresponding recess.

The invention therefore also provides a device consisting of a clutch release unit and a connection element consequently, device which comprises at least one peripheral groove formed in one of the two modules consisting of the clutch and connecting element. This groove can in this way be connected to an opening in the other of the two modules consisting of the declutching unit and the connection element, so that a connection can be created between an actuator and a stop of declutching unit release.

The groove can be provided in the coupling of the declutching unit or in the connection element.

Thanks to such a device, the connection between the actuator and the declutching stop is also made independently of an angle of rotation of the declutching unit, so that the declutching unit can be assembled without any problem.

An easy assembly of a clutch can be ensured by the fact that before fixing the clutch housing, a declutching unit is arranged on the friction disc side, behind a control spring. This creates a connection between the declutching unit and the rest of the clutch, so that the entire device can be assembled in one mounting operation.

Such an assembly is particularly simple to carry out if, after being placed behind the control spring, the declutching unit is connected to a connection element. This is preferably done after the clutch housing has been attached.

It goes without saying that with the clutch described, it is only of secondary importance that the flow of forces passes from the clutch plate or from the pressure plates to the shafts of the friction discs or vice versa. To this extent, the invention also includes devices in which modules qualified by the term "output" are used as input, that is to say drive.

Other advantages, objectives and properties of the present invention are explained with the aid of the description of the accompanying drawings, on which three clutches according to the invention have been shown, by way of illustration. In these drawings:

FIG. 1 a first embodiment of a clutch according to the invention, in section,

FIG. 2 a top view of the tangential leaf springs of the clutch, according to FIG. 1,

FIG. 3 a profile view of the external control springs of the clutch according to FIG. 1,

Figure 4 the connection between the control spring and the clutch release finger according to Figure 1, in section,

Figure 5 the device of Figure 4 in top view,

FIG. 6 a variant of the device illustrated in FIG. 4,

FIG. 7 a second embodiment of a clutch according to the invention, by a representation similar to that of FIG. 1, and

Figured a third embodiment of a clutch according to the invention, by a representation similar to those of Figures 1 and 7.

In the embodiment illustrated in Figure 1, two friction discs 10, 20 are arranged on either side of a clutch plate 30 and can be applied against the clutch plate by means of plates pressure 11 and 21. To do this, suitable coupling faces 31 and 32 are provided respectively on the clutch plate 30.

The clutch plate 30 is rigidly connected to a casing 40, which is in turn fixed to a dual mass flywheel 41 or to a similar device.

Via this, the clutch is in operational connection with a drive device or a motor.

In Figure 1, the clutch is shown in the unsolicited state. This means that the declutching unit 50 is not exposed to a force. As can be seen, in this non-stressing situation, the pressure plate 11 is applied by a spring washer 12 against the friction disc 10 or the associated coupling face 31 (normally closed NC). The other pressure plate 21 is on the other hand open and let the corresponding friction disc 20 rotate freely (normally open NO).

The casing 40 surrounds the two friction discs 10, 20 and the two pressure plates 11, 21 and has, at its end oriented opposite the flywheel with two masses 41, bearing projections 42, 43 on which take support of the control springs 13, 22 respectively. Each of the control springs has lever arms 13a, 13b, both radially inside and radially outside (referenced by way of example in FIGS. 3 to 5) which compensate each other in their action following centrifugal force. In addition, these control springs 13, 22 are arranged substantially radially. The radially outer lever arms 13b have openings 13c in which disengaging fingers 14 engage with lugs 15. The disengaging fingers are connected together by a retaining ring 16. The retaining ring 16 as well as the recesses 13c and the tenons 15 collect the centrifugal forces.

FIG. 6 represents an alternative embodiment, in which a lug 13c 'of the control spring 13' surrounds disengaging fingers 14 '.

The declutching unit 50 has two declutching declutching stops 51 and 52, each operationally connected to control springs 13 and 22. If these declutching declutching stops 51, 52 are stressed, they exert opposing forces on the springs 13 and 22. They are then set in motion via two hydraulic lines 53. The hydraulic lines 53 open into openings 44 provided for their part in a tube 55 of the declutching unit 50. The tube 55 is arranged in a corresponding recess of a connecting element 56, recess in which rotate two grooves 57 into which open the openings 54. The grooves 57 are in turn provided with actuators not shown.

As can be seen, the clutch release bearing 52 is in fact a clutch bearing, since it closes the pressure plate 21 under load against the clutch plate 30.

As can be seen directly in fig. 1, the forces of the two declutching stops 51 and 52 compensate each other. In view of the elastic characteristic of the leaf spring 12, this however cannot always be fully ensured. To increase the degree of compensation, the tangential leaf springs 17 of the pressure plate 11, in any case present in the state of the art, are designed to oppose a disengagement. To do this, the springs are dimensioned so that there is a greater compensation, in particular in the event of relatively large disengagement forces or paths.

The friction discs 10 and 20 have different linings. While the friction disc 10 comprises a normal "soft" clutch lining, as used for motor vehicles, the lining of the friction disc 20 has been chosen as a rigid sintered lining. In addition, the two friction discs 10 and 20 include axially directed zones 18 and 23 as well as recesses 24 (not illustrated in the friction disc 10), which allow an oscillation of the friction disc and a radial suspension. Thus, any misalignment of the shafts 1 and 2 not mounted on the coupling side can be corrected. As can be seen, the shafts 1 and 2 as well as the declutching unit 50 are arranged coaxially with one another.

The axial zones 18 and 23 also create a free space in which the declutching unit 50 can advance.

In the device described in FIG. 1, the inner shaft 1 is coupled to the odd ratios and the reverse gear of a gearbox, while the cylindrical outer shaft 2 is coupled to the even ratios.

To avoid heat accumulation, the casing 40 has an opening 44.

In the example of embodiment described, the steel was chosen for the spring washer 12, in order to be able to apply the necessary pressure forces. The lightest possible material has been chosen for the control springs 13 and 12, so that the influences of centrifugal forces are reduced. Preferably aluminum can be used.

The exemplary embodiment illustrated in FIG. 8 corresponds, so to speak, to that illustrated in FIG. 1. In this one, the declutching stops 51, 52 have been inverted with respect to their radial position relative to the other, compared to the embodiment shown in Figure 1. Therefore, there are slightly changed control springs 13 "and 22”.

In its effect, the embodiment illustrated in FIG. 7 is also identical to the embodiments described above, except that the declutching stops 51 ′ and 52 ′ are formed as declutching units with radial action. As these declutching units 51 ′ and 52 ′ are effective only radially, the construction of the entire device can be narrower. On the other hand, a relatively more complex lever device 13a '", 13b", and 22a ", 22b" is used.

Claims (37)

1. Clutch comprising at least two friction discs (10, 20), two corresponding coupling faces (31, 32) and two associated pressure plates (11, 21), which can be actuated individually. 2. Clutch according to claim 1, characterized in that the two coupling faces (31, 32) are provided on at least one module which is rigidly connected to a clutch housing (40). 3. Clutch according to claim 1 or 2, characterized in that the two coupling faces (31, 32) are arranged on a clutch plate (30). 4. Clutch according to claim 3, characterized in that the clutch plate (30) is arranged in the center between the two pressure plates (11,21). 5. Clutch according to one of claims 1 to 4, characterized by a housing (40) which envelops the two friction discs (10,20) and / or the two pressure plates (11,21). 6. Clutch according to claim 5, characterized in that the casing (40) has radial openings (44). 7. Clutch according to one of claims 1 to 6, characterized by a casing (40) which compensates for the control forces of two control springs (13, 22; 13 '; 13 ", 22"; 13a "', 13b '", 22a"', 22b '") which are associated respectively with a pressure plate (11, 21). 8. Clutch according to one of claims 1 to 7, characterized in that in a non-stressing situation, a first of the two pressure plates (11, 21) is pressed against the associated coupling face (31). 9. Clutch according to claim 8, characterized in that the first of the two pressure plates (11, 21) is applied against the friction disc (10) by means of a spring washer (12). 10. Clutch according to one of claims 1 to 9, characterized in that in a non-stressed situation, a second of the two pressure plates (11, 21) let the friction disc (20) corresponding to rotate freely. 11. Clutch according to one of claims 1 to 10, characterized in that the friction discs (10, 20) are connected to two shafts (1, 2) arranged concentrically. 12. Clutch according to one of claims 1 to 11, characterized by at least one friction disc (10, 20) slightly oscillating. 13. Clutch according to claim 12, characterized in that the friction disc is elastic in the radial direction. 14. Clutch according to claim 12 or 13, characterized in that the friction disc (10, 20) has recesses (24) which are provided in an area of the friction disc (10, 20) which connects the friction lining to the shaft (1, 2) corresponding in the direction of rotation. 15. Clutch according to one of claims 12 to 14, characterized in that the friction disc (10, 20) has zones (18, 23) directed axially. 16. Clutch according to one of claims 1 to 15, characterized in that the lining of the first of the two friction discs (10, 20) is soft and the lining of the second of the two friction discs (10, 20) is hard. 17. Clutch according to claim 16, characterized in that the soft friction disc (10) is operationally connected to a shaft (1) for a first gear and / or a reverse gear. 18. Clutch according to one of claims 1 to 17, characterized by at least one control spring (13, 22; 13 '; 13 ", 22"; 13a1 ", 13b'", 22a '", 22b"') which has, both radially internally and radially externally, at least one lever arm (13a, 13b). 19. A clutch according to claim 18, characterized in that an additional mass is provided on the radially outer lever arm (13b). 20. Clutch according to one of claims 1 to 19, characterized by a declutching unit (50) with two declutching stops (51, 52; 51 ', 52') which are actuable individually and each interact with one of the two pressure plates (10,20). 21. Clutch according to claim 20, characterized in that at least one clutch release bearing (51, 52; 51 ', 52') is actuated hydraulically. 22. Clutch according to claim 20 or 21, characterized in that at least one declutching stop (51, 52; 51 ', 52 ’) is operatively connected to an electric actuator. 23. Clutch according to one of claims 20 to 22, characterized in that a first clutch release bearing (51, 52; 51 ') is arranged radially outside the second clutch release bearing (51, 52; 52 *). 24. Clutch according to one of claims 20 to 23, characterized in that the declutching unit (50) is arranged coaxially with at least one shaft (1, 2). 25. Clutch according to one of claims 20 to 24, characterized in that in a stressing situation, the declutching stops (51, 52) are exposed to a force directed in the opposite direction. 26. Clutch according to one of claims 20 to 25, characterized in that at least one release bearing (51, 52; 51 ', 52') is operatively connected to a control spring (13, 22; 13 ' ; 13 ", 22"; 13a "', 13b"', 22a '", 22b" ") which is designed so that in a non-stressed situation, it acts against the clutch release bearing (51, 52; 51 ', 52') with a holding force, preferably a holding force of a hydraulic control for the clutch release bearing (51, 52; 51 ', 52'). 27. Clutch according to one of claims 1 to 28, characterized in that a control element, preferably a declutching element is provided between a first of the two control springs (13, 22; 13 '; 13 ", 22 "; 13a" ', 13b' ", 22a '", 22b "'), preferably an external lever arm (13b) of the control spring (13), and a first of the two pressure plates (10). 28. Clutch according to claim 27, characterized in that the control element comprises at least one disengaging finger (14) which is preferably arranged axially between the control spring (13, 22; 13 '; 13 ", 22 ", 13a '", 13b "', 22a '", 22b' ") and the pressure plate (10). 29. Clutch according to claim 28, characterized in that the control element has several release fingers (14) which are connected together by a retaining ring (16). 30. Clutch according to one of claims 1 to 29, characterized in that the first pressure plate (10) is connected to a casing (40) by at least one tangential leaf spring (17), this tangential leaf spring (17) exerting a force opposite to the disengaging force. 31. Clutch according to one of claims 1 to 30, characterized by a declutching unit (50) provided with a connecting pipe (55) with symmetry of revolution with respect to an axis of rotation of the clutch. 32. Clutch according to claim 31, characterized in that the connection pipe (55) has at least one connecting element (54) ensuring the connection of at least one clutch release bearing to an actuator. 33. Connection element for a clutch release unit, preferably according to one of claims 31 or 32, characterized by a recess with symmetry of revolution with respect to an axis of rotation of the clutch. 34. Connection element according to claim 33, characterized in that in the recess, there is provided at least one connection element (57) ensuring the connection of at least one declutching stop (51, 52; 51 ', 52 ') to an actuator. 35. Device comprising a clutch release unit or a clutch and a corresponding connection element (56), characterized by at least one peripheral groove (57) in one of the modules made up of the unit release (50) and / or the connecting element (56) which is connected to an opening (54) in the other module (56) consisting of the declutching unit (50) and / or the 'connecting element (56), so that there is connection between an actuator and a declutching stop (51,52; 51', 52 '). 36. Method for assembling a clutch, according to which, before fixing a clutch housing (40), a declutching unit (50) is arranged on the friction disc side behind a control spring (13, 13 ', 13 ", 13a '", 13b "', 22a '", 22b "'). 37. Method according to claim 36, characterized in that after its placement behind the control spring (13, 13 ', 13 ", 13a"', 13b '", 22a'", 22b "'), the unit clutch (50) is connected to a connecting element (56). SHORT "Clutch, connecting element and device formed therefrom and method of assembling a clutch In the case of a clutch with at least two friction discs, two coupling faces and two pressure plates associated therewith, which can be actuated individually, must allow a process of smooth engagement and disengagement of the respective friction discs.