WO2012110123A1

WO2012110123A1 - Bearing arrangement for activating a clutch

Info

Publication number: WO2012110123A1
Application number: PCT/EP2011/070336
Authority: WO
Inventors: Ernst Masur; Etienne Rueff; Georg Von Petery
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2011-02-16
Filing date: 2011-11-17
Publication date: 2012-08-23
Also published as: DE102011004193A1

Abstract

Bearing arrangement for activating a clutch, comprising a disengagement bearing which can be moved axially in order to disengage and engage the clutch, and an axially fixed supporting bearing comprising an inner ring and an outer ring with roller bodies running between them, wherein the disengagement bearing (3) and the supporting bearing (11) are arranged lying coaxially one in the other, wherein the pitch circle diameter Tk of the supporting bearing (11) on which the roller bearings (14) lie and the roller body diameter dw are selected in such a way that a ratio Tk/dw > 8 is satisfied.

Description

Name of the invention

Bearing arrangement for actuating a coupling Description

FIELD OF THE INVENTION The invention relates to a bearing arrangement for actuating a clutch, comprising a release bearing axially movable for engagement and disengagement of the clutch, and an axially fixed support bearing comprising an inner or outer ring with rolling bodies running therebetween. Background of the invention

Bearing arrangements of the type described are used in the field of single or double clutches or corresponding hybrid systems. The actually disengaging or retracting operation of the downstream clutch is obtained via the axially movable release bearing. For this purpose, usually the inner ring of the axially movable release bearing with corresponding actuating levers of a diaphragm spring or the like, which are pivotally mounted in the clutch housing connected. To disengage the release bearing is moved against the actuating lever, so that they pivot about a pivot bearing, over which the force acting on a pressure plate of a clutch disc axial forces are reduced, so that the tension of the clutch disc reduced to a these opposing second clutch disc and consequently the clutch is disengaged. The engagement process is carried out in the reverse manner, namely, when the release bearing is moved back in the opposite direction, so that the operating lever of the clutch disc are relieved and swing back due to their spring properties, so that the clutch disc again in solid, frictional engagement with the opposing second Clutch disc is brought. The release bearing is arranged for this purpose in a conventional manner on a corresponding axially movable guided sleeve, which in turn is coupled with an actuating mechanism, via which the axial movement can be initiated.

About the axially fixed support bearing, the bearing assembly, so ultimately the actuator for the clutch, axially and radially supported. The support bearing is usually a combined radial and thrust bearing, which is supported bearing arrangement with its inner ring, while it is radially held in the mounting position with its outer ring on a suitable housing member of the coupling and axially fixed by a suitable collar or circlips, etc., wherein the Arrangement can also be reversed. About this support bearing with its both radial and in particular also axia- len support, which is ultimately connected between the actual coupling device on the one hand and the associated actuator, namely the disengagement device with the bearing assembly according to the invention on the other hand, avoids that axial forces on the coupled shafts, in particular the Crankshaft, which is connected to the clutch, act, which can load their bearings.

The arrangement of the release bearing and the support bearing is usually such that both are arranged axially offset. This results in a considerable axial space, which requires the bearing assembly in the installation situation, but which is not always given due to the increasing compaction.

Summary of the Invention The invention is therefore based on the problem of specifying a bearing arrangement of the type mentioned, which is improved in terms of the required axial space. To solve this problem is provided according to the invention in a bearing assembly of the type described above, that the release bearing and the support bearing are coaxially arranged one inside the other, wherein the pitch circle diameter Tk of the support bearing on which the rolling elements are, and the rolling element diameter dw are selected such that a ratio Tk / dw> 8 is given.

According to the invention, instead of the axially staggered construction, a coaxially nested construction is realized, in which the release bearing is arranged coaxially in the support bearing located radially further outward. This results in that the axial length can be considerably reduced, since in the end ultimately hardly an axial offset is given, but both are coaxial with each other.

In this case, the inner diameter of the inner ring of the angular contact ball bearing is to be chosen as small as possible, so that a radially as compact as possible coaxial arrangement relative to the inner release bearing results in the diameter of the component on which the inner ring is supported. This is advantageous in that, in addition, the radial installation space can additionally be kept very small. In order to reduce the radial space even further, the invention proposes to optimize the dimensioning of the support bearing with respect to the ratio of the pitch diameter to Wälzkörperdurchmesser, namely to the effect that the Wälzkörperdurchmesser is chosen as small as possible, so that a ratio of the pitch circle diameter to Wälzkörperdurchmesser, ie Tk / dw> 8, preferably even Tk / dw> 10. However, the ratio Tk / dw should be <16.5. Due to the coaxial nesting arrangement of the two bearings, the pitch circle diameter of the support bearing inevitably increases, it is, based on conventional dimensions of the release bearing arranged in the support bearing> 72.5 mm. Too large a radial structure is now counteracted according to the invention by a reduction of the Wälzkörperdurchmessers, wherein the Wälzkörperdurchmesser is chosen so that adjusts a value corresponding to the above-described ratio. This means that due to the reduction of the rolling body diameter, compared to conventional bearing designs, can achieve a radial space reduction.

Overall, this results in a very compact bearing arrangement, which is optimized in terms of the required axial and radial space. At the same time, the bearing arrangement also allows the absorption of applied radial and axial forces to a considerable extent, as well as any radial offsets and tilting can be compensated to a certain extent. Furthermore, radial and axial vibrations are readily absorbed in the system.

To further reduce the axial space or narrowing of the overall structure contributes, if, as further provided according to the invention, the width b of the outer ring of the support bearing is selected such that a ratio between the width b and the rolling element diameter dw to b / dw <2 , 5, preferably with b / dw <2.3. In other words, the width of the outer ring, ie its axial dimension, is also reduced or adapted to the rolling element diameter, so that the ratio described above results. This leads to a very narrow structure. However, the ratio b / dw should be> 1.5.

An expedient development of the inventive concept provides for the pitch circle diameter Tk, the rolling body diameter dw and the width b to be selected such that the overall result is a design ratio Tk ^» dw / b> 35, preferably> 37. This design ratio is a measure of the radial and axial structure of a bearing. By appropriate choice of the ratio parameters for setting the ratio in the specified range, a generally suitable size ratio for a suitable bearing arrangement structure can be specified overall. However, the design ratio Tk ^» dw / b should be <65.

From the narrow structure results in that the support bearing has a total of a relatively small volume, equivalent to a small volume to Ingestion of lubricant needed to provide good lubrication. In order to keep the lubricant, usually a suitable grease, in the camp, the support bearing is sealed on both sides via a respective sealing ring. In addition, an expedient development of the invention provides for a lubricant groove to be provided on the inner ring and / or outer ring of the support bearing adjacent to the respective rolling body running surface, ie that the volume is structurally enlarged via the one or the two lubricant grooves, so that despite an extremely narrow bearing a sufficient Lubricant volume for receiving the lubricant is available.

As already described, the bearing, in which the rolling elements are preferably accommodated in a plastic cage, which is guided on the rolling body or on board depending on the load requirement, is sealed off via the sealing rings. In order to keep the self-heating of the support bearing as low as possible at high speeds and thus high speed characteristics, the seals are designed to be friction-optimized. h., That both the sealing ring geometry and the material used is chosen to cause the lowest possible friction. Furthermore, it is expedient if one or more vent grooves are provided on the respective sealing ring or in the outer or inner ring. These are used for venting and thus for pressure equalization, so that the contact pressure of the sealing lips is almost constant under all operating conditions.

Short description of the character

An embodiment of the invention is illustrated in the drawing and will be described in more detail below. Show it:

Figure 1 is a schematic representation in section of a bearing assembly according to the invention;

Figure 2 is a sectional view of a usable for a bearing assembly according to the invention bearing support of a first embodiment; Figure 3 is an enlarged detail sectional view of the support bearing of Figure 2;

Figure 4 is a sectional view of a usable for a bearing assembly according to the invention bearing support of a second embodiment;

Figure 5 is an enlarged detail sectional view of the support bearing of Figure 4;

Figure 6 is a sectional view of a usable for a bearing assembly according to the invention bearing support of a third embodiment;

Figure 7 is an enlarged detail sectional view of the support bearing of Figure 6;

Detailed description of the drawing

Figure 1 shows a schematic diagram of a bearing assembly 1 according to the invention in the assembly position, ie in the Verbausituation in the region of a coupling 2, which is shown here only partially. The coupling can be a single or double disc clutch or a hybrid system.

The bearing arrangement comprises on the one hand a release bearing 3, which is designed as an angular contact ball bearing and is arranged on a release sleeve 4, which is axially movable in a conventional manner, when a corresponding, not shown here closer actuator is actuated. About the axial movement of the release sleeve together with release bearing 3, the clutch is disengaged and engaged.

The release bearing 3 has in known manner an inner ring 5 and an outer ring 6, between which rolling elements, here balls 7, run. The inner ring 5 is mounted via an annular flange 8 in a conventional manner against actuating lever 9 of a diaphragm spring or the like of the clutch 2, which actuating lever 9 for disengaging the clutch, so if the release bearing 5 is moved to the left according to Figure 1, so that the actuating levers 9 associated clutch disc that the actuating levers 9 associated clutch disc is axially relieved and thus the clutch is opened. In a correspondingly reverse manner, the engagement or closing of the clutch takes place. The bearing assembly 1 further comprises an annular support member 10 to which a support bearing 1 1, here in the form of a ball bearing, is arranged with its inner ring 12. The support bearing 1 1 further comprises in known manner an outer ring 13 and between the rings rolling elements in the form of balls 14. The outer ring 13 is supported on a housing member 15 of the coupling 2, both axially and radially.

As Figure 1 shows, the release bearing 3 and the support bearing 1 1 coaxial with each other, d. h., That the support bearing 1 1, the release bearing 3 radially outwardly surrounds. It follows that this bearing arrangement, ie the arrangement comprising the two bearings 3 and 1 1, built low in axial terms.

In order to keep the radial structure also as small as possible, the support bearing 1 1 with respect to the parameters pitch circle diameter Tk and rolling element diameter dw designed such that preferably results in a ratio of Tk / dw of> 10 and preferably <16.5. Because due to the coaxial nesting of the two bearings 3 and 1 1 inevitably results in that the pitch circle diameter Tk of the support bearing 1 1, compared with previous axially offset bearing assemblies, increases. The counteracting the reduction of the Wälzkörperdurchmessers, thus the use of relatively small balls 13, wherein the diameter of the balls is chosen so that the ratio Tk / dw> 10 and <16.5. Of course, the outer ring is preferably chosen in its thickness so that it is as thin as possible, of course, taking into account the required strength properties. Furthermore, it is provided in the bearing assembly 1 according to the invention, to choose the width b of the outer ring 13 as small as possible, so that the support bearing 1 1 is as narrow as possible and is axially kleinbauend. The width b of the outer ring is chosen in relation to the rolling element diameter dw, in such a way that there is a ratio between the width b and the rolling element diameter dw, which is <2.5, preferably <2.3, and preferably> 1.5. Overall, according to the invention, the parameters pitch circle diameter Tk, rolling body diameter dw and width b are to be selected such that they give a design ratio Tk ^» dw / b of preferably> 37 and preferably <65.

FIGS. 2 and 3 show a first exemplary embodiment of a support bearing 1 according to the invention. This comprises an inner ring 12 which is internally toothed, balls 14 fixed in a cage 16 and an outer ring 13. The inner race is adjacent to the raceway 17 there on which roll the balls 14, a circumferential lubricant groove 18 is provided. Likewise, the outer ring 14 has a further lubricant groove 20 adjacent to the raceway 19 there, on which the balls 14 roll. This is the volume, which is sealed by two sealing rings 21 which are fixed in the example shown in corresponding retaining grooves 22 or the like on the outer ring, slightly increased, so that despite the small width of the support bearing 1 1 results in a sufficiently large lubricant space. The seals 21 extend to the inner ring 12. They are designed to minimize the self-heating of the support bearing 1 1 at high speeds as low friction optimized, both in terms of the material as well as their investment configuration. The support bearing 1 1 is positioned in an arrangement shown in Figure 1 relative to the release bearing 3, d. h., it surrounds this radially. The pitch circle diameter Tk is exemplarily 72.5 mm in the exemplary embodiment shown. The width b is exemplary 14 mm. The diameter of the balls 14 is exemplary 7, 144 mm. This results in the following relationships:

Tk / dw = 72.5: 7, 144 = 10, 148. Ratio b / dw = 14: 7, 144 = 1, 96.

Construction ratio Tk'dw / b = 72.5 ^» 7, 144: 14 = 37.0. Figures 4 and 5 show a further embodiment of a usable and inventively dimensioned support bearing 1. This in turn consists of an inner ring 12 and an outer ring 13, between which in turn run in a cage 16 guided rolling elements in the form of balls 14. In turn, two sealing rings 21 are provided, which are fixed on the outside ring side in corresponding receptacles 22.

The pitch circle diameter Tk is in this support bearing 1 1, for example, 79 mm, the width b is z. B. 13, 1 mm, the rolling element diameter dw is, for example, 6.35 mm. This results in the following results:

Ratio Tk / dw = 79: 6.35 = 12.44.

Ratio b / dw = 13, 1: 6.35 = 2.06. Construction ratio Tk ^» dw / b = 79 ^» 6,35: 13, 1 = 38,29.

Thus, this support bearing is dimensioned such that the conditions defined according to the invention arise. Finally, FIGS. 6 and 7 show a third variant according to the invention of a support bearing 11, in turn comprising an inner ring 12 and an outer ring 13, between which balls 17 guided in a cage 16 run. The volume located therebetween is in turn sealed by two sealing rings 21, which are also fixed here in corresponding receptacles 22 on the outer ring. Unlike the previously described embodiments, in which according to Figures 2 and 3 on the inner and outer ring each had a lubricant groove was provided, or see the embodiments of Figures 4 and 5, no lubricant grooves have, is here only on the outer ring 13th a lubricant groove 20 is formed. The inner ring is designed very narrow in this embodiment, as far as its radial width.

The pitch circle diameter Tk in this embodiment is, for example, 91 mm, the width b is, for example, 16.7 mm, while the rolling body diameter is, for example, 7.938 mm. This results in the following relationships:

Ratio Tk / dw = 91: 7,938 = 1 1, 46.

Ratio b / dw = 16.7: 7.938 = 2.10.

Construction ratio Tk ^» dw / b = 91 · 7.938: 16.7 = 42.25. Here, too, the ratios defined according to the invention move as a result of the respective dimensioning of the corresponding components in the areas according to the invention.

The various embodiments of the support bearing, all of which are to be installed in the release bearing radially encompassing arrangement, has in common that they all defined so that the respective relevant conditions arise. In all embodiments, the ratio Tk / dw> 10, the ratio b / dw <2.3, and the design ratio Tk ^» dw / b> 37, also the ratios are in each case initially defined interval.

LIST OF REFERENCE NUMBERS

1 bearing arrangement

2 clutch

3 release bearing

4 release sleeve

5 inner ring

6 outer ring

7 ball

8 ring flange

9 operating lever

10 support component

1 1 support bearing

12 inner ring

13 outer ring

14 ball

15 housing component

16 cage

17 career

18 lubricant groove

19 career

20 lubricant groove

21 sealing ring

22 holding groove

Claims

claims

1 . Bearing arrangement for actuating a clutch, comprising a release bearing for releasing the clutch and axially movable and an axially fixed support bearing comprising an inner and an outer ring rolling therebetween rolling elements, characterized in that the release bearing (3) and the support bearing (1 ) are coaxially arranged inside each other, wherein the pitch circle diameter Tk of the support bearing (1 1) on which the rolling elements (14) lie, and the

Rolling diameter dw are chosen such that a ratio Tk / dw> 8 is given.

2. Bearing arrangement according to claim 1, characterized in that the ratio Tk / dw> 10.

3. Bearing arrangement according to claim 1 or 2, characterized in that the width b of the outer ring (13) of the support bearing (1 1) is selected such that a ratio between the width b and the rolling body diameter dw to b / dw < 2.5 results.

4. Bearing arrangement according to claim 3, characterized in that the ratio b / dw <2.3. 5. Bearing arrangement according to one of the preceding claims, characterized in that the pitch circle diameter Tk, the rolling body diameter dw and the width b are selected such that a construction ratio Tk ^» dw / b> 35 results. 6. Bearing arrangement according to claim 5, characterized in that a construction ratio Tk ^» dw / b> 37 results. Bearing arrangement according to one of the preceding claims, characterized in that on the inner ring (12) and / or on the outer ring (13) of the support bearing (1 1) adjacent the Wälzkörperlauffläche (17, 19) a lubricant groove (18, 20) is provided.

Bearing arrangement according to one of the preceding claims, characterized in that the support bearing (1 1) is sealed on both sides via a respective sealing ring (21).

Bearing arrangement according to claim 8, characterized in that one or more vent grooves on the respective sealing ring (21) or the inner or the outer ring (12, 13) are provided.

10. Bearing arrangement according to one of the preceding claims, characterized in that the rolling elements (14) are held in a cage (16) made of plastic.