WO2011079833A1

WO2011079833A1 - Crankshaft pulley

Info

Publication number: WO2011079833A1
Application number: PCT/DE2010/001462
Authority: WO
Inventors: Lászlo MAN
Original assignee: Schaeffler Technologies Gmbh & Co. Kg
Priority date: 2009-12-30
Filing date: 2010-12-13
Publication date: 2011-07-07
Also published as: DE112010005054A5; DE102010054336A1

Abstract

The invention relates to a crankshaft pulley (1) for transferring torque between a crankshaft (4) and a pulley, comprising a freewheel (8). The invention is characterised in that said freewheel is combined with a hydraulically actuatable coupling (10) in the crankshaft pulley.

Description

Crankshaft pulley

The invention relates to a crankshaft pulley for transmitting a torque between a crankshaft and a belt drive, with a freewheel.

From the German patent application DE 195 35 889 A1 discloses a one-way clutch is known, which is arranged between a pulley and a shaft. The known overrunning clutch is suitable for driving a generator and is part of a pulley, which serves to drive the generator. By using the one-way clutch an internal damping is made possible, so that the torque transmission of the traction mechanism is improved. European Patent EP 0 980 479 B1 discloses a belt drive system having a generator clutch freewheel clutch comprising a torsion coil spring and a one-way clutch mechanism. As a result, the driving torques of the generator pulley can be transmitted to a hub yielding. In addition, the generator pulley can be uncoupled from the hub in one direction. From the German patent DE 196 36 628 C1 a freewheel with a clamping body is known, which is formed by a circumferentially extending gap, elastically deformed coil spring. European Patent EP 0 782 674 B1 discloses a crank-shaft decoupler with a directionally switched clutch which serves to selectively transmit rotational forces between a mounting hub and a pulley. German Offenlegungsschrift DE 10 2005 029 351 A1 discloses a drive wheel for driving an auxiliary unit of an internal combustion engine with a damping device.

The object of the invention is to provide a space-neutral solution for a decoupled from the crankshaft crankshaft pulley according to the preamble of claim 1. In this case, the crankshaft pulley according to the invention should in particular a start-stop operation, a stationary climate and generator operation, preferably with a pulse starting possibility including Kurbelwellentilger, and / or damping of rotational irregularities in the belt drive, allow.

The object is achieved in a crankshaft pulley for transmitting torque between a crankshaft and a belt drive, with a freewheel, characterized in that the freewheel in the crankshaft pulley with a hydraulically actuated clutch combined. In a normal generator mode, the clutch is open. Due to the freewheel rotational irregularities of the crankshaft can be reduced in the belt drive. When the crankshaft is stopped and the starter generator continues to drive the belt drive, preferably including the air conditioning compressor, the clutch is still open and the freewheel is overhauled with little frictional resistance. If an internal combustion engine, which is also referred to as an internal combustion engine, are started, then the hydraulically actuated clutch is actively closed. The crankshaft is thereby accelerated to a starting speed. In this case, the angular momentum of the belt drive is advantageously utilized, which considerably reduces the required starting time. When the engine is running in generator mode, the clutch is reopened. The torque transmission and at the same time the reduction of rotational irregularities in the belt drive are taken over by the freewheel. The freewheel preferably has a locking direction in which a torque transmission takes place. In the opposite direction of rotation, which is also referred to as freewheeling direction, no torque transmission takes place by the freewheel.

A preferred embodiment of the crankshaft pulley is characterized in that the clutch is designed as a multi-plate clutch. The multi-plate clutch is preferably designed to run dry.

Another preferred embodiment of the crankshaft pulley is characterized in that a hydraulic piston for actuating the clutch is arranged in the crankshaft pulley. The hydraulic piston is preferably rotatably disposed in the crankshaft pulley.

A further preferred embodiment of the crankshaft pulley is characterized in that the hydraulic piston is accommodated in the axial direction movable back and forth in a piston housing which is non-rotatably connected to the crankshaft. Axial means in the direction or parallel to the axis of rotation of the crankshaft pulley.

Another preferred embodiment of the crankshaft pulley is characterized in that the piston housing is non-rotatably connected to a Außenlameilenträger the clutch. The rotationally fixed connection is preferably designed positively.

Another preferred exemplary embodiment of the crankshaft pulley is characterized in that at least one absorber mass is attached to the outer lamella carrier is. The absorber mass is preferably fastened to the outer disk carrier with the interposition of a rubber track.

A further preferred embodiment of the crankshaft pulley is characterized in that at least one hydraulic channel extends through the piston housing and a freewheel inner ring of the freewheel. The freewheel inner ring is rotatably connected to the crankshaft, for example by means of a feather key.

Another preferred embodiment of the crankshaft pulley is characterized in that a pulley track is attached to a freewheel outer ring, which constitutes an inner disc carrier of the clutch. In the radial direction of the freewheel is arranged with a freewheel cage between the freewheel inner ring and the freewheel outer ring.

Another preferred embodiment of the crankshaft pulley is characterized in that a rotary union for hydraulic medium for actuating the clutch is attached to a central screw which is fixed to the crankshaft. The rotary feedthrough preferably comprises a coupling body, which is mounted rotatably in the central screw by means of a bearing device.

Another preferred embodiment of the crankshaft pulley is characterized in that the crankshaft pulley is mounted on the crankshaft or the central screw. For this purpose, at least one bearing device is preferably arranged in the radial direction between the freewheel inner ring and the freewheel outer ring, which comprises, for example, a ball bearing and a roller bearing. The freewheel is preferably arranged in the axial direction between the ball bearing and the roller bearing.

Further advantages, features and details of the invention will become apparent from the following description in which, with reference to the drawings, an embodiment is described in detail. Show it:

1 shows a crankshaft pulley according to the invention in longitudinal section through the crankshaft;

FIG. 2 shows a three-dimensional sectional view of the crankshaft pulley from FIG. 1; Figure 3 shows an enlarged detail of Figure 1 with freewheel and clutch;

Figure 4 shows a further enlarged detail of Figure 1 only with the coupling;

FIG. 5 shows a further enlarged detail from FIG. 1 with a rotary inlet;

FIG. 6 is a perspective view of a central screw of the crankshaft pulley of FIG. 1;

Figure 7 is a perspective view of a freewheel inner ring of the Kurbeiwellenriemenscheibe of Figure 1;

FIG. 8 is a perspective view of an outer disk carrier of the crankshaft pulley of FIG. 1;

FIG. 9 is a perspective view of a freewheel outer ring of the flexible shaft pulley of FIG. 1 and FIGS

Figures two different perspective view of a piston housing of the 10 and 11 crankshaft pulley of Figure 1.

In the figures 1 to 11 a Kurbeiwellenriemenscheibe 1 according to the invention is shown in various representations and individual parts. The crankshaft pulley 1 comprises a pulley track 2, which is also referred to as a pulley or belt track for a short time and serves to couple a belt of a belt drive with a belt starter generator and / or with an air conditioning compressor. The crankshaft pulley 1 is attached by means of a central screw 5 to a crankshaft 4 of a motor vehicle. The crankshaft 4 is driven by an internal combustion engine, which is also referred to as an internal combustion engine.

According to one essential aspect of the invention, a freewheel 8, a clutch 10 and a torsional vibration damping device 12, which comprises an absorber mass 14, are integrated into the crankshaft pulley 1. The clutch 10 is designed as an actively switchable dry blade coupling executed. About the clutch 10, the crankshaft pulley 1 can be connected depending on demand with the crankshaft 4.

In a normal generator mode, the clutch 10 is open. Due to the freewheel e rotational irregularities of the crankshaft 4 can be reduced in the belt drive. When the crankshaft 4 is stopped and the starter generator continues to drive the belt drive including the air conditioning compressor, the clutch 10 is still open and the freewheel 8 is overhauled with low frictional resistance. This operation is also called stand climate operation.

If the engine is to be started, then the clutch 10 is actively closed. The crankshaft 4 is thereby accelerated to the starting speed. The angular momentum of the belt drive is advantageously utilized, which considerably shortens the required starting time.

The central screw 5 comprises a screw head 16, from which a screw shaft 17 extends with a thread. The central screw 5 is screwed with the screw shaft 17 in a central threaded blind hole of the crankshaft 4. With the help of a key 20, a freewheel inner ring 21 is rotatably connected to the crankshaft 4 and the central screw 5. For hydraulic sealing 21 sealing rings 22, 23 are received in corresponding grooves between the central screw 5 and the freewheel inner ring.

On the freewheel inner ring 21, a freewheel outer ring 28 is rotatably supported by means of two bearing devices 25, 26. The bearing device 25 is designed as a ball bearing with cage. The bearing device 26 is designed as a roller bearing with cage. In the axial direction between the two storage facilities 25 and 26 of the freewheel 8 is arranged. Axially outwardly the bearings 25 and 26 are sealed by seals.

The freewheel outer ring 28 constitutes an inner disk carrier for inner disks 29, which are frictionally connected to outer disks 30, which are non-rotatably connected to an outer disk carrier 31. The outer disk carrier 31 is integrally connected to a coupling ring disk 33, which is rotatably connected by the feather key 20 with the crankshaft 4.

Radial outside is on the outer disk carrier 31 by means of a rubber track 35 the

Tilgermasse 14 attached. The absorber mass 14 fills an annular space which is delimited by the outer disk carrier 31 and the belt track 2. From the belt track 2 extends a flange 38 radially inward. Via the flange 38, the belt track 2 is fastened by means of rivet connection elements 37 to a pressure plate 36.

The pressure plate 36 extends radially outward from the freewheel outer ring 28 and has substantially the shape of a circular disk with a rectangular cross section. The inventive connection of the absorber mass 14 via the outer disk carrier 31 directly to the crankshaft 4 provides the advantage that the life of the rubber track 35 is extended because the absorber mass 14 is not involved in the torque flow.

In the outer disk carrier 31 in addition to the outer disk 30 is another

Hinged outer plate 39, which is non-rotatably, but axially movably connected to the outer disk carrier 31. Similarly, the inner plate 29 is rotatably, but axially movably connected to the freewheel outer ring 28. The inner plate 29 is clamped with the interposition of friction linings between the outer plates 30, 39, when a hydraulic piston 41 is moved in the axial direction of the pressure plate 36.

The hydraulic piston 41, together with a piston seal 42, can be moved back and forth in an axial direction in a Koibengehäuse 44 and actuated by hydraulic pressure medium, that is movable in the axial direction of the pressure plate 36. To reset the hydraulic piston 41 is a return spring 45 which is hooked with an end turn in the piston housing 44 and with an opposite end turn in the outer plate 39. In this case, the return spring 45 is biased in the axial direction to train that the outer plate 39 abuts in the axial direction of the piston housing 44, as long as the hydraulic piston 41 is not actuated.

For actuation of the hydraulic piston 41, the latter is acted upon by a hydraulic channel with a hydraulic medium pressure on the sealing side. The hydraulic passageway includes three interconnected hydraulic passage portions 46, 47, 48. The hydraulic passage portion 46 extends through the piston housing 44 to the freewheel inner race 21. The hydraulic passage portion 47 extends between the piston housing 44 and the center screw 5 through the freewheel inner race 21. The hydraulic portion 48 extends from the freewheel inner ring 21 through the central screw 5 into a central blind hole 50, which is recessed in the central screw 5. -In the central blind hole 50 of the central screw 5, a coupling body 52 is rotatably supported with the interposition of a seal 53 and a spacer 54 by means of a bearing device 55. By the rotatable mounting of the coupling body 52 in the central screw 5, a rotary inlet 56 is provided, can be supplied via the hydraulic medium in the blind hole 50. With the interposition of a seal 58, a hydraulic line 60 is connected to the coupling body 52 by means of a screw 59. The hydraulic line 60 extends past the crankshaft pulley 1, for example to a hydrostate, through which hydraulic medium can be conveyed via the rotary inlet 56 into the piston housing 44 for actuation of the clutch 10.

By the return spring 45, the clutch 10 is biased in its open position. About the rotary inlet 56 of the hydraulic piston 41 can be selectively applied with hydraulic pressure to close the clutch 10 active. Thereby, the crankshaft 4 can be accelerated to start speed. If the internal combustion engine is running in generator mode, then the hydraulic pressure acting on the hydraulic piston 41 can be turned off or taken off so that the rotary hydraulic piston 41 is reset by the return spring 45 and the clutch 10 is opened again.

The designed as a dry multi-plate clutch clutch 10 requires low actuation pressures, which is advantageous for the hydraulic rotary feedthrough 56. The rotary feedthrough 56 is designed for a minimum required diameter, which is very advantageous in the high speeds occurring during operation of the crankshaft 4. Moreover, it is advantageous that the rotary inlet or rotary feedthrough 56 is pressurized only during the short startup process. Otherwise, the rotary inlet 56 is depressurized, whereby the wear can be significantly reduced.

In FIG. 6 it can be seen that the central screw 5 comprises not only one hydraulic channel section 48 but at least one further hydraulic channel section 63. The hydraulic passage portion 63 is connected to a hydraulic passage portion 65 which, as seen in FIG. 7, is provided in the freewheel inner race 21 in addition to the hydraulic passage portion 47. The freewheel inner ring 21 further comprises an axially extending groove 66, which serves to partially receive the key 20. The freewheel inner ring 21, like the freewheel outer ring 28, is preferably made of a rolling bearing material to impart sufficient mechanical strength and wear resistance to the bearing races formed thereon. In FIG. 8 it can be seen that the outer cam carrier 31 has an internal toothing 68 in which the outer discs 30, 39 are suspended for a rotationally fixed connection. In addition, the outer cam carrier 31 has a total of four positive-locking regions 69, which serve for the rotationally fixed connection between the outer cam carrier 31 and the piston housing 44. Finally, the outer cam carrier 31 has radially inwards on the coupling ring disk 33 an axial groove extending in the longitudinal direction 70, which serves to partially receive the key 20.

In FIG. 9 it can be seen that the freewheel outer ring 28 has a bearing raceway 72 radially inward and an outer toothing 73 radially outward. The outer toothing 73 is used to mount the inner plate 29 in order to connect them in rotation with the freewheel outer ring 28.

In FIGS. 10 and 11, it can be seen that the piston housing 44 has a

Annulus 75 for reciprocally movable receiving the hydraulic piston 41 has. In Figures 10 and 11, the piston housing 44 is shown in perspective in two different views. In FIG. 10 it can be seen that, in addition to the hydraulic channel section 46, a further hydraulic channel section 76 opens into the annular space 75 diametrically opposite one another. In FIG. 11 it can be seen that the piston housing 44 has four form-fitting regions 78, which are formed complementary to the positive-engagement regions 69 on the outer lamella carrier 31.

About the interlocking positive-locking portions 78 and 69, the piston housing 44 can be rotatably connected in a simple manner with the Außenlameilenträger 31. The hydraulic transitions between the piston housing 44 and the outer cam carrier 31 are sealed by O-rings. The belt track 2 can be made of a softer material than the freewheel inner ring 21 and the freewheel outer ring 28. The production can be carried out, for example, by high-grade forming of a sheet material. The belt track 2 is centered on the flange 38 on the freewheel outer ring 28 and connected by the Nietverbindungselemente 37 fixed to the pressure plate 36 of the freewheel outer ring 28. LIST OF REFERENCE NUMBERS

Crankshaft pulley

Pulley groove

crankshaft

central screw

freewheel

clutch

Torsional vibration damping device

absorber mass

screw head

screw shaft

Adjusting spring

Freewheel inner ring

seal

Storage facility

Freewheel outer ring

outer disk

External disk carrier

Coupling ring disk

rubber track

printing plate

Nietverbindungselement

flange

outer plate

hydraulic pistons

piston seal

piston housing

Return spring

Hydraulic channel section

Hydraulic channel section central blind hole

coupling body

poetry

spacer

Storage facility

rotary Joint

poetry

screw

hydraulic line

Hydraulic channel section

groove

internal gearing

Form-fit area

longitudinal groove

Bearing race

external teeth

annulus

Hydraulic channel section

Form-fit area

Claims

claims

A crankshaft pulley for transmitting a torque between a crankshaft (4) and a belt drive, comprising a freewheel (8), characterized in that the freewheel (8) in the crankshaft pulley (1) is combined with a hydraulically actuated clutch (10).

2. crankshaft pulley according to claim 1, characterized in that the

Clutch (10) is designed as a multi-plate clutch.

3. crankshaft pulley according to one of the preceding claims, characterized in that a hydraulic piston (41) for actuating the clutch (10) in the crankshaft pulley (1) is arranged.

4. crankshaft pulley according to claim 3, characterized in that the hydraulic piston (41) in the axial direction reciprocally movable in a piston housing (44) is received, which is non-rotatably connected to the crankshaft (10).

5. crankshaft pulley according to claim 4, characterized in that the piston housing (44) rotatably connected to an outer disk carrier (31) of the coupling is connected.

6. crankshaft pulley according to claim 5, characterized in that on the outer disk carrier (31) at least one absorber mass (14) is mounted.

7. crankshaft pulley according to one of claims 4 to 6, characterized in that extending at least one hydraulic passage through the piston housing (44) and a freewheel inner ring (21) of the freewheel.

8. crankshaft pulley according to claim 7, characterized in that a pulley track (2) on a freewheel outer ring (28) is fastened, which represents an inner disc carrier of the clutch (10).

9. crankshaft pulley according to claim 8, characterized in that a rotary feedthrough (56) for hydraulic medium for actuating the clutch (10) on a Central screw (5) is attached, which is attached to the crankshaft (4).

10. crankshaft pulley according to claim 9, characterized in that the crankshaft pulley (1) on the crankshaft (4) and the central screw (5) is mounted.