DE102012211679A1 - Pulley assembly for connection to crankshaft of internal combustion engine of motor car, has drive shaft changed between closed position and open position upon rotation of coupling element opposite to driving direction - Google Patents

Abstract

The assembly (10) has a coupling element (16) coupled to a guide pin (30) for moving the coupling element in an actuating direction (18). The guide pin is movable between a closed position in which a pulley clutch (12) i.e. dog clutch, is closed, and an open position in which the pulley clutch is open. A drive shaft (14) remains in the closed position or the open position upon rotation of the coupling element in a driving direction. The drive shaft is changed between the closed position and the open position upon rotation of the coupling element opposite to the driving direction. An independent claim is also included for a method for coupling a pulley assembly.

Description

The invention relates to a pulley arrangement and method for coupling a pulley arrangement, by means of which, for example, a crankshaft of an internal combustion engine with ancillaries, such as an air compressor, can be connected and via which, for example with the aid of a starter torque can be introduced into the crankshaft to the internal combustion engine to start.

Out DE 101 48 961 A1 a pulley arrangement with a pulley for driving ancillaries is known, which is connected via a planetary gear with a crankshaft of the internal combustion engine.

There is a continuing need to simplify the construction of pulley assemblies.

It is the object of the invention to provide a pulley arrangement and a method for operating an accessory of a motor vehicle, by means of which a simple construction of the pulley arrangement is made possible.

The object is achieved by a pulley arrangement with the features of claim 1 and a method having the features of claim 10. Preferred embodiments of the invention are specified in the dependent claims.

According to the invention, a pulley arrangement is provided for connection to a drive shaft, in particular crankshaft of an internal combustion engine of a motor vehicle, with a pulley for driving ancillaries, a coupling element, in particular a claw of a dog clutch, for opening and / or closing a pulley clutch for coupling the drive shaft with the pulley , A link pin coupled to the coupling element for moving the coupling element in an actuating direction of the coupling element and a slotted guide, in which the guide pin in a circumferential movement relative to the slotted guide between a closed position in which the pulley clutch is closed, and an open position, which the pulley clutch is open, is movable, wherein the guide pin is coupled to the coupling element such that the guide pin upon rotation of the coupling element in a r driving direction of the drive shaft remains in the closed position or the open position and changes in a rotation of the coupling element against the drive direction of the drive shaft between the closed position and the open position.

Due to the guide pin guided in the slotted guide pin, the guide pin can execute a movement counter to the drive direction of the drive shaft according to the track of the slide guide movement through which the coupling element along the operating direction of the pulley clutch can be moved to close the pulley clutch or to open , Since a starter, in particular a starter generator, can be coupled to the coupling element, in particular indirectly via the belt pulley of the pulley arrangement, it is possible with the aid of the starter to briefly rotate the coupling element against the drive direction in order to move the guide pin between the open position and the closed position Adjust and thereby operate the pulley clutch. Since the starter can be designed as an electric machine, it is particularly easy to provide a reversal of the direction of rotation of the starter. The starter can thereby not only fulfill the function via the pulley arrangement in the drive shaft to initiate a torque for starting the internal combustion engine but also the function of coupling and disengaging the pulley assembly with the drive shaft without requiring a separate actuator for this function. Since no additional actuator is required for coupling the pulley assembly to the drive shaft, a simple construction of the pulley assembly is made possible. In particular, the components for a separate actuator system and a corresponding energy supply can be saved.

With the aid of the pulley arrangement, in the closing position of the coupling element of the drive shaft via the pulley and a driven by the pulley traction means an accessory, in particular an air compressor can be driven, with the aid of an air conditioner of the motor vehicle can be operated. If the air conditioning compressor is to be operated with the aid of the starter ("stationary air conditioning"), it is sufficient to operate the starter briefly against the driving direction, so that the coupling element is moved to the open position and the air conditioning compressor is driven by the starter without stationary drive shaft to be braked or blocked. In order to start the internal combustion engine when the stationary air conditioning mode is active, the coupling element can again be briefly moved counter to the drive direction with the aid of the starter in order to close the belt pulley clutch. In the closed position of the coupling element can subsequently via the starter, in particular via a traction means with the pulley coupled, a starting torque are introduced into the drive shaft to start the engine of the motor vehicle ("starter mode"). Preferably, when the internal combustion engine is started, the starter in the closed position of the coupling element can in particular optionally be operated as a generator in order to generate storable electrical energy with the aid of the starter ("generator operation"). It is also possible in the closed position of the coupling element during operation of the internal combustion engine by the starter to initiate an additional torque to provide, for example, briefly requested peak moments can ("boost operation").

The drive direction of the drive shaft is understood to be that direction of rotation of the drive shaft into which the drive shaft rotates during normal operation of the internal combustion engine when the internal combustion engine introduces a torque into the drive shaft. The slotted guide can be formed by a component which can be positioned in particular motion-resistant and is connected, for example, with a fixed housing. Preferably, the slotted guide is circumferentially formed circumferentially, so that there is an endless track formed by the slotted guide for the guide pin. The guide pin may, for example, have a bent end inserted into the raceway of the slide guide. The guide pin is used in particular with a spring force in the raceway of the guide slot, so that the guide pin within the track of the slide guide surveys and depressions can follow and in particular can be performed over provided in the raceway ramps. This makes it possible to provide for the guide pin in the career of the slide guide metastable rest positions and / or to block a return movement against a previous movement. For example, the track may have isolated or a plurality of substantially sawtooth-shaped ramps arranged one behind the other, each of which can block a return movement of the link pin. Particularly preferably, the coupling element is part of a form-fitting coupling coupling, in particular a dog clutch, so that regardless of any occurring wear effects in the closed position of the coupling element over the substantially entire life of the clutch is given a safe torque transmission.

In particular, the guide pin is supported by a support bearing in the circumferential direction relative to the coupling element movable on the coupling element, wherein the guide pin by means of a freewheel with the coupling element is rotatably coupled. The guide pin can exert an actuating force on the coupling element via the support bearing in order to move the coupling element into an open or a closed position of the belt pulley coupling. At the same time, the guide pin can be decoupled from the rotation of the coupling member by the bearing action of the support bearing, so that the guide pin is not moved by the slotted guide when the coupling element is rotated and no switching of the pulley clutch is intended. Due to the freewheel, the guide pin can be automatically coupled in rotation with the coupling element for switching the pulley clutch.

Preferably, the freewheel is configured such that the freewheel opens when the coupling element rotates in the drive direction of the drive shaft, and the freewheel locks when the coupling element rotates counter to the drive direction of the drive shaft. Due to the freewheel, the guide pin, in spite of the bearing effect of the support bearing rotatably coupled to the coupling element, so that during a reverse rotation of the coupling element against the drive direction of the drive shaft of the guide pin in the sliding guide can be performed from the open position to the closed position or from the closed position to the open position to to move the coupling element in the direction of actuation and to switch the pulley clutch. When the coupling element rotates in the drive direction, overrunning the freewheel, so that the guide pin is disconnected from the coupling element and no longer rotates when in the closed state of the pulley clutch in normal operation of the internal combustion engine, the coupling element rotates together with the drive shaft.

Particularly preferably, the coupling element is spring-loaded with the aid of a Anfederelements in the closing direction. In the event of a defect, the pulley clutch can thereby be automatically closed, so that starting of the internal combustion engine and operation of the ancillary components during operation of the internal combustion engine is ensured and damage to the internal combustion engine is avoided. Furthermore, the spring force provided by the Anfederelement can facilitate a smooth closing of the pulley clutch. At the same time, the spring force provided by the Anfederelement can act on the guide pin and press the guide pin against a side wall of a track of the slotted guide. As a result, the guide pin easier follow the career of the slotted guide. Furthermore, it is possible to thread the guide pin easier in a branch of the track, so that the guide pin takes a predictable way even with a complicated geometry of the slotted guide.

In particular, several, in particular substantially identical, are circumferentially formed, slide guides arranged one behind the other. As a result, only a small rotation of the coupling element against the drive direction by an angular amount, which can be significantly less than a full turn, required to switch the pulley clutch. The tracks of subsequent slide guides can preferably merge into one another, so that the guide pin can easily switch from one guide slot in the subsequent slide guide without additional career. Particularly preferably, the transition from the career of a link guide in the career of the subsequent link guide via a ramp with return, so that the guide pin can not get back into the first link guide. The risk that an intentional shift operation for the pulley clutch unintentionally omitted, we thereby reduced.

Preferably, the slide guide is connected to a circumferentially circumferential return path for guiding the slide pin against movement of the guide pin against the drive direction, wherein the slide guide is tapered connected to the return path, that the guide pin can be threaded in a movement in the drive direction in the slide guide. Due to the particular substantially circular circulating return path of the guide pin follow a particularly simple geometry, so that even at a high rotational speed and a large swept angle of rotation of the counter to the drive direction rotating coupling element, the stress on the guide pin is kept low. Upon completion of the reverse rotation of the coupling element of the guide pin may move slightly in the drive direction by the guide pin is pressed, for example with a spring force against a side wall of the raceway, which is inclined relative to the circumferential direction. The guide pin can thereby be automatically threaded after completion of the reverse rotation of the coupling element of the return path in the slotted guide and its intended position, in particular the closed position, occupy. Preferably, after the threading of the guide pin in the slide guide first, the closed position and only subsequently the open position for the guide pin reachable.

Particularly preferably, the slotted guide between the closed position and the open position of the sliding pin on a return to block a return movement of the sliding pin on. As a result, it can be avoided that the guide pin can return to the original position after a sufficient swept distance. Preferably, the guide pin can only reach the subsequent position after passing the return. The risk that an intentional shift operation for the pulley clutch unintentionally omitted, we thereby reduced. The recess can be formed in particular by a ramp within the track of the slotted guide, wherein the ramp can be designed in particular substantially sawtooth-shaped.

In particular, the slide guide has a stop for blocking a further movement of the guide pin against the drive direction of the drive shaft, wherein the guide pin, in particular by an impressed spring force, at a decrease in acting on the stop contact force in the closed position and / or in the open position is movable , This can ensure that the guide pin reaches its intended position without being able to move back to the previous position. Preferably, the stop also blocks a further rotation of the coupling element against the drive direction. This blocking of the rotation of the coupling element can be used as a signal that the switching process for the pulley clutch is completed so far that the sliding pin safely reaches its next position and further movement of the coupling element against the drive direction is no longer required. The switching time for switching the pulley clutch can thereby be minimized without jeopardizing safe switching.

Preferably, a snap spring acting on the coupling element is provided for positioning the coupling element between the closed position and the open position, wherein in particular the snap spring provides a higher resistance force in the closed position than in the open position. The snap spring can assume two stable states, whereby two stable positions can be specified for the coupling element, which correspond to the closed position and the open position of the pulley clutch. The snap spring designed in particular as a snap plate spring can provide a sufficiently large moment of resistance in the two stable states, so that the coupling element is not pushed out of the closed position and / or the open position during the usual forces occurring during operation. However, the moment of resistance of the snap spring is sufficiently low that the coupling element can be moved by a movement of the sliding pin from the closed position to the open position and from the open position to the closed position. Preferably, the spring force of the snap spring in a transition from the one stable state in the other stable state, the movement of the slide pin in the raceway of the slotted guide support. In particular, by the provided resistance forces in the two stable states of the snap spring can be taken into account that in the closed position of the pulley clutch in operation higher forces can act on the coupling element than in the open position. At the same time relative movements of the coupling element are reduced to the rest of the clutch in the closed position, while in the open position, a slight switching with a low actuation force is made possible. In particular, in the closed position due to the higher resistance force of the snap spring, a correspondingly high torque can be transmitted, so that, for example, a starting torque for starting the internal combustion engine can be transmitted.

The invention relates to a remote belt drive with a can be coupled to a drive shaft of an automotive engine pulley assembly, which may be as described above and further educated, coupled to the pulley arrangement traction means coupled to the traction means accessory, in particular air compressor, and a starter, in particular starter generator for starting the motor vehicle engine by introducing a torque into the pulley assembly. Since no additional actuator is required for coupling the pulley arrangement with the drive shaft, a simple construction of the belt drive is made possible.

The invention further relates to a method for coupling a pulley assembly, which may be as described above and further educated, with a drive shaft of an automotive engine, wherein a coupled to the pulley arrangement starter, in particular starter generator, a torque against the drive direction of the drive shaft in the pulley assembly initiates, wherein the, in particular short-term, against the drive direction of the drive shaft introduced into the pulley assembly torque is used to move the coupling element between the closed position and the open position. Since no additional actuator is required for coupling the pulley assembly to the drive shaft, a simple construction of the pulley assembly is made possible. Briefly, rotation of the coupling element is understood to be less than fifty, in particular less than twenty, preferably less than five, and with particular preference less than one full revolution.

The invention will now be described by way of example with reference to the accompanying drawings with reference to preferred embodiments, wherein the features shown below, both individually and in combination may represent an aspect of the invention. Show it:

1 FIG. 2 is a schematic diagram of a first embodiment of a belt disk arrangement in an open position; FIG.

2 : A schematic outline of the pulley assembly 1 in a closed position and

3 : A schematic schematic representation of a second embodiment of a pulley assembly in a closed position.

In the 1 and 2 very schematically illustrated pulley arrangement 10 is via a pulley clutch 12 with a designed as a crankshaft of an internal combustion engine drive shaft 14 coupled. For this purpose, the pulley arrangement 10 a coupling element 16 on that part of the pulley clutch 12 is. In the illustrated construction game is the pulley clutch 12 designed as a dog clutch, so that the coupling element 16 as a claw of the dog clutch is configured. The coupling element 16 is along an actuating direction 18 displaceable and with the aid of a Anfederelements 20 towards an in 2 shown closed position in which the pulley clutch 12 closed, spring loaded. The Anfederelement 20 is on a pulley 22 tethered, to which a traction means can be connected, with the help of one of the drive shaft 14 with closed pulley clutch 12 introduced torque ancillaries, such as an air conditioning compressor of an air conditioner, an oil pump or fuel pump to drive. Furthermore, over the pulley 22 an electric starter, in particular a starter generator, introduced a torque to closed when the pulley clutch 12 a torque in the drive shaft 14 initiate and with the drive shaft 14 To start connected internal combustion engine of a motor vehicle. In the in 1 shown open position of the pulley clutch 12 is the pulley arrangement 10 from the drive shaft 14 uncoupled so that the starter can operate an air conditioning compressor with the internal combustion engine switched off. The pulley 22 is this via a pulley bearing 24 relatively rotatable to the drive shaft 14 stored.

To the pulley clutch 12 between the in 1 shown open position and the in 2 Turning closed position shown, is the coupling element 16 with one in a career 26 a slide tour 28 guided scenery pin 30 coupled. Between the coupling element 16 and the scenery pin 30 is a support camp 32 interposed so that the scenery pin 30 relative to the coupling element 16 but turn a movement along the direction of actuation 18 can transmit to the coupling element. At the same time is the coupling element 16 over a freewheel 34 with a slider 36 connectable, in which the scenery pin 30 along the actuation direction 18 is movably guided. When the coupling element 16 in the drive direction of the drive shaft 14 turns, is the freewheel 34 in the overhull mode, so the slider 36 is not moved and the scenery pin 30 not within the slotted guide 28 is moved. When the coupling element 16 from the starter against the drive direction of the drive shaft 14 turns, the freewheel locks 34 so that the scenery pin 30 within the slotted guide 28 rotated and moved in the illustrated image plane down. The scenery pin 30 thereby passes in a circumferentially continuous return path 38 in which the scenery pin 30 can be moved along a long distance at a high speed without being exposed to greater loads. When the movement of the coupling element 16 Stop against the drive direction and the coupling element 16 to be rotated in the drive direction, the guide pin can 30 automatically in the against the return path 38 according to beveled opening career 26 the slide tour 28 thread and into the in 2 shown closed position. The threading can be done by the Anfederelement 20 get supported. Additionally or alternatively, the return path 38 in the area of the junction of the raceway 26 in the return path 38 have a ramp, which is a return 40 formed. As a result, the guide pin 30 in a reverse movement in a counter to the drive direction rotating coupling element 16 the return 40 overcome by a movement along the ramp but with an opposite movement at the return 40 strike and automatically into the career path 26 are forced. It is also possible that several slide guides 28 arranged one after the other are formed by recesses formed by ramps 40 merge.

When the scenery pin in the in 2 shown closed position, performs a further short-term rotation of the coupling element 16 contrary to the drive direction, that the guide pin along the track 26 is moved while the pulley clutch 12 opens. The scenery pin 30 can at a significant opening of the pulley clutch 12 at one through a side wall of the track 26 trained stop 42 strike, with the scenery pin 30 by that of the coupling element 16 applied torque against the stop 42 is pressed. When the movement of the coupling element 16 Stop against the drive direction and the coupling element 16 to be rotated in the drive direction, takes the contact force between the guide pin 30 and the stop 42 so that the guide pin by the of the Anfederelement 20 applied contact pressure in the in 1 shown open position is pressed. For safety's sake, just before the scenery pin 30 the stop 42 can be provided a ramp, which makes a return 40 trains, so the scenery pin 30 in case of diminishing contact force, do not inadvertently fall into the in 2 shown closed position is moved back.

At the in 3 illustrated embodiment of the pulley assembly 10 is compared to the in 1 and 2 illustrated pulley arrangement 10 instead of the Anfederelements 20 a snap spring 44 between the drive shaft 14 and the coupling element 16 provided in the in 3 shown closed position and the corresponding open position assumes a metastable state. Because the snap spring 44 at the transition between the closed position and the open position, a sudden movement on the guide pin 30 imprinted, it is possible by recesses formed by ramps 40 omit without an unintentional return movement of the guide pin 30 to risk. Furthermore, both for the achievement of the closed position and for reaching the open position in each case a stop for the guide pin 30 provided, leaving a return path 38 can be omitted.

LIST OF REFERENCE NUMBERS

10

 Pulley arrangement

12

 Pulley clutch

14

 drive shaft

16

 coupling member

18

 operating direction

20

 Anfederelement

22

 pulley

24

 Pulley bearing

26

 career

28

 link guide

30

 link pin

32

 support bearings

34

 freewheel

36

 pusher

38

 Return path

40

 return

42

 attack

44

 catch spring

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10148961 A1 [0002]

Claims (10)

Pulley arrangement for connection to a drive shaft ( 14 ), in particular crankshaft of an internal combustion engine of a motor vehicle, with a pulley ( 22 ) for driving ancillaries, a coupling element ( 16 ), in particular a claw of a dog clutch, for opening and / or closing a pulley clutch ( 12 ) for coupling the drive shaft ( 14 ) with the pulley ( 22 ), one with the coupling element ( 16 ) coupled guide pin ( 30 ) for moving the coupling element ( 16 ) in an actuating direction ( 18 ) of the coupling element ( 16 ) and a slide guide ( 28 ), in which the guide pin ( 30 ) during a movement in the circumferential direction relative to the slotted guide ( 28 ) between a closed position in which the pulley clutch ( 12 ) is closed, and an open position, the pulley clutch ( 12 ) is open, is movable, wherein the guide pin ( 30 ) in such a way with the coupling element ( 16 ), that the guide pin ( 30 ) upon rotation of the coupling element ( 16 ) in a drive direction of the drive shaft ( 14 ) remains in the closed position or the open position and upon rotation of the coupling element ( 16 ) against the drive direction of the drive shaft ( 14 ) changes between the closed position and the open position. Pulley assembly according to claim 1, characterized in that the guide pin ( 30 ) via a support bearing ( 32 ) in the circumferential direction relative to the coupling element ( 16 ) movable on the coupling element ( 16 ) is supported, wherein the guide pin ( 30 ) by means of a freewheel ( 34 ) with the coupling element ( 16 ) is rotatably coupled. Pulley arrangement according to claim 2, characterized in that the freewheel ( 34 ) is configured such that the freewheel ( 34 ) opens when the coupling element ( 16 ) in the drive direction of the drive shaft ( 14 ) turns, and the freewheel ( 34 ) locks when the coupling element ( 16 ) against the drive direction of the drive shaft ( 14 ) turns. Pulley arrangement according to one of claims 1 to 3, characterized in that the coupling element ( 16 ) with the aid of a Anfederelements ( 20 ) is spring-loaded in the closing direction. Pulley arrangement according to one of claims 1 to 4, characterized in that in the circumferential direction a plurality, in particular substantially identically shaped, slide guides ( 28 ) are arranged one behind the other. Pulley arrangement according to one of claims 1 to 5, characterized in that the sliding guide ( 28 ) with a circumferentially revolving return path ( 38 ) for guiding the guide pin ( 30 ) during a movement of the guide pin ( 30 ) is connected against the drive direction, wherein the slotted guide ( 30 ) bevelled at the return track ( 38 ), that the guide pin ( 30 ) in a movement in the drive direction in the slotted guide ( 28 ) is threadable. Pulley arrangement according to one of claims 1 to 6, characterized in that the sliding guide ( 28 ) between the closed position and the open position of the sliding pin ( 30 ) a return ( 40 ) for blocking a return movement of the sliding pin ( 30 ) having. Pulley arrangement according to one of claims 1 to 7, characterized in that the sliding guide ( 28 ) a stop ( 42 ) for blocking a further movement of the guide pin ( 30 ) against the drive direction of the drive shaft ( 14 ), wherein the guide pin ( 30 ), in particular by an impressed spring force, with a decrease in the stop ( 42 ) acting pressing force in the closed position and / or in the open position is movable. Pulley arrangement according to one of claims 1 to 8, characterized in that one on the coupling element ( 16 ) acting snap spring ( 44 ) for positioning the coupling element ( 16 ) is provided between the closed position and the open position, wherein in particular the snap spring ( 44 ) provides a higher resistance in the closed position than in the open position. Method for coupling a pulley arrangement ( 10 ) according to one of claims 1 to 9 with a drive shaft ( 14 ) of an automotive engine, in which one with the pulley arrangement ( 10 ) coupled starter, in particular starter generator, a torque counter to the drive direction of the drive shaft ( 14 ) in the pulley arrangement ( 10 ), wherein, in particular, for a short time, counter to the drive direction of the drive shaft ( 14 ) in the pulley arrangement ( 10 ) introduced torque for moving the coupling element ( 16 ) between the closed position and the open position is used.

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