WO2012083927A1

WO2012083927A1 - Belt drive having a transmission ratio shifted by a lever actuator

Info

Publication number: WO2012083927A1
Application number: PCT/DE2011/002114
Authority: WO
Inventors: Lars Schumann; Wolfgang Reik; Oswald Friedmann; Lászlo MAN; Alexander Dreher; Peter Greb
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2010-12-24
Filing date: 2011-12-13
Publication date: 2012-06-28
Also published as: DE102011088326A1; DE112011104572A5

Abstract

The invention relates to a belt drive of a drive train of a motor vehicle, comprising a planetary gear train, which shifts a transmission ratio between a starter generator and an internal combustion engine and which has a ring gear that can be connected rigidly to a housing by means of a brake, a web connected to a crankshaft of the internal combustion engine of the drive train and having planet gears over the circumference, and a sun gear connected in a rotationally locked manner to a rotor of the starter generator and to at least one auxiliary unit, and a shifting device for controlling a torque direction between the rotor and the crankshaft. In order to be able to control the brake and the shifting device in a simple manner and to avoid erroneous shifting, the brake and the shifting device are each actuated by an actuating unit, and the actuating units are activated jointly by means of a single lever actuator.

Description

Belt drive with translation switched by a lever actuator

The invention relates to a belt drive of a drive train of a motor vehicle with a planetary gear shifting a transmission between a starter and an internal combustion engine with a ring fixed to the housing by means of a brake, connected to a crankshaft of the internal combustion engine of the drive train web with planetary gears arranged over the circumference and one with a Rotor of the starter generator and at least one accessory rotatably connected sun gear and a switching device to control a torque direction between the rotor and the crankshaft.

Generic belt drives are known for example from the German patent applications DE 199417 705 A1, DE 10 2004 060 991 A1 and DE 10 2007 021 233 A1. This is the object of a starter generator, which should ensure the generator function, the starting function of the internal combustion engine, a torque assist the engine (Boost function) and a stationary air conditioning by driving a trapped in the belt drive air compressor with a stationary engine, as effectively and with low power and to design a small space. Here, a transmission, preferably a planetary gear is provided which provides two gear ratios, so that the required by the starter generator range of action is covered by a variation of the operating speeds of the starter generator. On the one hand, the ratio of the planetary gear and, on the other hand, the direction of the moment flux between the rotor of the starter generator and the crankshaft of the internal combustion engine are to be controlled. The control of the planetary gear is based on a selectively freely rotating or fixed to the housing by means of a brake ring gear and the control of the torque flow, a switching device. This may be a dog clutch for connection or separation of the rotor and crankshaft or be formed from two mutually opposing, switchable freewheels.

As a possibility for actuating friction clutches lever actuators are known for example from DE 10 2004 009 832 A1. In this case, a traverse is moved by an electric motor, which displaces the fulcrum of a prestressed lever and thus an axial displacement.

CONFIRMATION COPY Storage causes a lever end, which exerts an axial force on a plate spring of a friction clutch.

Object of the present invention is the simple and error-free development of an operation of the brake and switching device of the belt drive.

The object is achieved by a belt drive of a drive train of a motor vehicle having a planetary gear which can be connected to a transmission by means of a brake, a ring gear connected to a crankshaft of the internal combustion engine of the drive train with planetary gears arranged over the circumference and one with a rotor of the starter generator and at least one accessory rotatably connected sun gear and a switching device to control a torque direction between the rotor and crankshaft, solved, the brake actuated by a first actuator and the switching device of a second actuator and a common operation of both actuator units by means of a single lever actuator is provided. By applying the brake and the switching device by means of a single lever actuator, the kinematics of the operation of the operating units can be coordinated so that no errors and synchronization errors between the brake and switching device occur. Rather, desired switching sequences can be defined defined. Furthermore, costs and space can be saved by the operation of the operating units of the brake and switching device by means of a single lever actuator. It may be advantageous if both actuating units are acted upon axially by a lever of the lever actuator and, where appropriate, a necessary actuation in another - radial and / or circumferentially - direction of the switching device in particular kinematically by means of a corresponding change in movement, for example by means of a transmission is performed ,

According to a preferred embodiment, the lever actuator is arranged by means of a tilting joint on a motor housing of the internal combustion engine. In this case, for example, a housing of the lever actuator with the motor housing of the internal combustion engine or attached to this, preferably a structural unit connected to a lever actuator receiving base plate. The housing is in this case connected by means of a tilting joint tiltable with the base plate or the motor housing. The housing forms a first lever, a second lever is in the housing on an axially effective energy storage to form a He- arranged belpunktes. In this case, one of an electric motor, for example by means of a spindle drive radially displaceable traverse between the two levers under bias of the axially effective energy storage is shifted. By the displacement of the traverse, such as a roller block with rollers that roll on the two levers, a lever arm of the second lever relative to the housing and thus the first lever is axially displaced, whereby the actuator units are acted upon axially and thus brake and switching unit according to their geometric arrangement relative to the levers and formed in the housing attacks simultaneously or successively acted upon.

The first actuating unit is preferably designed as a disc brake with two on both sides on a non-rotatably associated with the ring gear, for example, attached to this or integrally connected thereto brake disc formed on each one lever brake shoes. The brake shoes are preferably clamped in the open state of the brake relative to the base plate or the motor housing by means of axially effective energy storage and are braced against the action of these axially against the brake disc and the brake disc and thus the ring gear fixed to the housing and thus form with displaced traverse the planetary gear a state in which the translation of the planetary gears, the sun gear connected to the rotor and the planetary gears receiving and rotationally connected to the crankshaft web is set, for example in the amount of 3: 1, while freely rotating ring gear and blocking freewheeling block of the gearbox is set (1: 1). The brake shoes can be accommodated floatingly and / or transverse force-supporting on the base plate or on the motor housing, for example, by means of fastening means engaging the housing.

The second actuating unit may be an axially arranged between the first and second lever slide, which is preferably acted upon by the second lever on the opposite side of the first actuating unit. In this case, the slider may be biased, for example by means of a tensioned between the housing and slider energy storage against the lever element of the second lever, so that a first switching position of the switching device is set and the switching device is switched to the second switching state at axial displacement of the lever arm of the first lever. For example, the switching device may be a dog clutch, this

is preferably open when the brake is open. Alternatively, the switching device may include two alternately switchable freewheels containing clamp bodies which are arranged displaceable by means of a sprag cage on an inner star, wherein a circuit of freewheels, for example by clamping the clamp body on the counter-shaped ramps of the inner star and an outer ring of the freewheels by means of a displacement the sprag cage takes place, for example, in the circumferential direction. The conversion of the axial movement of the slide in the lever actuator in the corresponding movement of Schaltein- direction takes place by means of a kinematic element, for example, provided between slide and switching cable, pulled the rope from the slider against the action of an energy storage and disabled a first switching state and a second Switching state activated and holds until the traverse lever actuator zurückverlagert and the slide together with rope under the effect of the energy storage zurückverlagert and the first switching state is set again.

In order to provide energy-saving operation of the lever actuator, the electric motor and the spindle drive, which are preferably fastened to the housing, can be designed so that the traverse remains in the set position without current (self-locking). Alternatively, the traverse can be de-energized to a zero position in which the preferred settings of the brake are activated (in particular as part of a safety strategy). These may be, for example, an open brake, that is, a non-effective gear ratio of the planetary gear and a torque direction with a torque flow from the crankshaft to the rotor in order to achieve a generator operation of the starter generator. Another arrangement may provide that the switching device is switched in the torque flux direction in the zero position of the lever actuator, for example to achieve fast start and boost operations.

The invention will be explained in more detail with reference to the embodiment shown in Figures 1 to 8. Showing:

FIG. 1 shows a belt drive shown schematically,

FIG. 2 shows the belt drive of FIG. 1 in a schematically represented view,

FIG. 3 shows a schematically illustrated lever actuator for controlling the belt drive of FIGS. 1 and 2,

FIG. 4 shows a schematic illustration of the lever actuator during a start, boost or belt release operation with the brake open,

FIG. 5 shows a schematic illustration of the lever actuator during a generator 6 shows a schematic representation of the lever actuator during a start, boost or generator operation with the brake engaged,

FIG. 7 shows a 3D view of the planetary gear unit with lever actuator of the belt drive of FIG. 2

and

8 shows a section through the planetary gear unit with lever actuator of Figure 7.

1 shows a schematic representation of the drive train 1 of a motor vehicle with the internal combustion engine 2, the belt drive 3, the friction clutch 4, the transmission 5 and the drive wheel. 6

The internal combustion engine drives with its crankshaft 8 both the transmission 5, as

Manual transmission, automated manual transmission, dual clutch transmission and the like may be formed as well as the belt drive 3 at. The belt drive 3 contains the starter generator 7 whose rotor 9 rotationally, for example coaxially or by means - not shown - pulleys and belts with the crankshaft 8 of the internal combustion engine by means of the opposite effective and by means of the lever actuator not shown, switching device according to the invention in the form of freewheels 10, 11th is provided connectable. The first freewheel 10 locks and switches the torque flow from the crankshaft 8 to the rotor 9 and separates the torque flow from the rotor 9 to the crankshaft 8, whereas the second freewheel 11 switches the torque flow from the rotor 9 to the crankshaft 8 and locks and the torque flow in the reverse Direction separates. The freewheels 10, 11 are switched alternatively. Between the rotor 9 and the crankshaft 8, the planetary gear 12 is further connected, the ring gear 13 fixed to the housing by means of the brake 14, for example, with the motor housing 21 of the engine 2 can be connected. The sun gear 15 is rotationally connected to the rotor 9. The intermeshing between the ring gear 13 and sun 15 planet gears 16 are received on the web 17. The web 17 is rotationally connected to the crankshaft 8.

Furthermore, at least one auxiliary unit 18 is rotationally connected to the rotor 9, for example, integrated by means of a pulley in the belt of the belt drive 3. In the embodiment shown, the auxiliary unit 18 is formed by the air conditioning compressor 19, which is rotationally connected with or without fixed translation with the rotor 9. The crankshaft 8, the pulley damper 20 is associated with a rotational fit, which can be designed as a damper and / or damper.

By appropriate operation of the freewheels 10, 11 and the brake 14 by means of the not shown, all actuating functions controlling lever actuator (actuator) corresponding operating states of the drive train 1 are controlled. Here, the brake 14 and the freewheels control the ratio of the planetary gear 12 and thus the torque fluxes between the rotor 9 and the crankshaft 8. Depending on the operating state of the engine 2 and the starter generator 7, several advantageous operating states of the drive train 1, in the following figures. 4 to 6 is discussed in detail. When setting the operating conditions of the brake 14 comes to lastschaltenden function of the planetary gear 12 to a crucial function. In order to avoid jerky torque distributions between the two gear ratios of the planetary gear 12, the brake 14 is actuated by an actuation path from the completely transmitting torque, that is, the ring gear 13 slip-free housing-connected state to a free rotatability of the ring gear 13 of a stored characteristic dependent.

2 shows schematically the belt drive 3 in view with the crankshaft 8, the starter generator 7 with the rotating direction of the arrow rotor 9 and the tension rollers 22. The belt 23 connects the components of the belt drive 3 rotationally, optionally further - not shown - in the belt drive 3 can be driven by a separate pulley or integrated into one of the listed components. On the crankshaft 8, the not explicitly shown transmission / actuator unit 24 is seated with the planetary gear, the actuator units and the lever actuator.

Figure 3 shows schematically and in section the Hebelaktor 25, said switching means formed of the ^■ freewheels 10, 11 26 and (to the ring gear 13 figure ^ acting brake 14 is actuated. The Hebelaktor 25 is together as a structural unit with the motor housing to the The base plate 27 receives the housing 28 with limited tilting by means of the tilting joint 29. The electric motor 30, which radially displaces the crossbar 31 by means of the spindle gear 32, is arranged on the housing 28. The traverse 31 rolls by means of rollers 33, 34 on the surfaces of the levers 35, 36 and forms for the pivotable relative to the housing 28 by means of energy storage 37 axially supported lever 35, the fulcrum 38, the radial displacement of the crossbar 31 to an axial displacement of Lever arm 39 leads. As a result, the lever arm 39 actuates the actuating units 40, 41 of the brake 14 or the switching device 26. For this purpose, the actuating unit 40 from the brake disc 42 and the brake shoes 43, 44 disposed on both sides, 44 formed by not shown, axially effective energy storage against the stops 45, 46 of the housing 28 are biased so that when not acting lever arm 39, the brake 14 is opened. The brake shoes 43, 44 are axially displaceable relative to the base plate 27, floating and supporting transverse forces by means of the receptacle 47.

The actuating unit 41 is formed by the slide 48, which is biased by the axially effective energy storage 49 against the lever arm 39 and whose axial travel is limited by the stop 50 on the housing 28. Within this axial travel of the slider 48 controls the two switching positions of the switching device 26. For this purpose, the slider 48 is connected to the cable 51, the rope 52 displaces the clamping body 53 receiving sprag cage 54 so that it along the ramps 55, 56 of the inner star 57 shifts be and thus mutually the freewheels 10, 11 of the switching device 26 switch.

The following figures 4 to 6 explain the function of the lever actuator 25 based on typical operating conditions. FIG. 4 shows the lever actuator 25 in a state in which the traverse 31 assumes a position opposite the lever arm 39 with respect to the lifting point 38 on the lever arm 58. Here, the brake 14 is open. The brake shoes 43, 44 have due to the bias of the energy storage 59, 60 relative to the brake disk 42 clearance. The energy storage 60 continues to bias the housing 28 against the stop 61 of the base plate 27. The energy storage 37 rotate under support at the fulcrum point 38 so far that the slider 48 is axially displaced against the action of the energy storage 49 and the cable 51 is relaxed so far that the energy storage 62 can move the clamping body cage 54. As a result, the clamping body 53 shift to the ramps 55, so that the freewheel 11 is switched. This transmits torque from the rotor 9 (Figure 1) to the crankshaft 8 (Figure 1).

This results in the belt drive 3 (Figure 1) is an operating condition in which the internal combustion engine can be started with a non-switched ratio, so the crankshaft can be rotated by the rotor. The same operating state allows support of the internal combustion engine by the starter generator in boost mode. Furthermore, the freewheel 11 is in a belt shedding in overtaking, so that the crankshaft can overtake the shaft of the sun gear. FIG. 5 shows the operating state of the lever actuator 25 with traverse 31 displaced in the region of the lever point 38. As a result, the energy accumulators 37 lose their effect, so that the energy accumulator 49 actuates the cable pull 51 while the brake 14 is still open, and thus against the action of the clamping body cage 54 Can shift energy storage 62. As a result, the clamping body 53 are shifted to the ramps 56 of the inner star 57, so that the freewheel 10 is switched. As a result, a direction reversal of the torque flow is achieved, so that torque is transmitted from the crankshaft to the rotor. Here, the generator operation can be performed at higher speeds of the internal combustion engine in a suitable speed range of the starter generator. Furthermore, a stationary air conditioner can be carried out when the internal combustion engine is stationary, since the stationary crankshaft is overrun by the rotor and can be driven by the starter generator of the air conditioning compressor.

FIG. 6 shows the lever actuator 25 with the traverse 31 displaced maximally. As a result of the cross member 31 acting on the lever arm 39, the housing 28 lifts off the stop 61 of the base plate and the energy accumulators 59, 60 are compressed and the brake shoes 43, 44 engage in frictional engagement with the brake disk 42, so that the brake 14 is closed and the ring gear 13 (Figure 1) is braked fixed to the housing. As a result, the ratio of the planetary gear 12 (Figure 1) is switched and is effective between the rotor and the crankshaft. The circuit of the freewheel 10 is maintained, an unintentional circuit of the freewheel 11 (Figure 4) is excluded. Due to the arrangement of the freewheel 10 between the sun gear 15 (Figure 1) and web 17 (Figure 1), the freewheel 10 is always in overtaking, so that with the switched ratio 3: 1 at low speeds of the crankshaft of the starter generator with sufficiently high speeds in Generator operation can be operated and the internal combustion engine can be started by the starter generator with high rotor speeds. Furthermore, a boost operation of the internal combustion engine is possible with small rotational speeds by means of higher rotational speeds of the starter generator.

Figures 7 and 8 show a structural design of the gear actuator unit 24 with the lever actuator 25 and the planetary gear 12 in 3D view or in section. The housing 28 of the lever actuator 25 is connected by means of the tilting joint 29 with the base plate 27. The electric motor 30 drives by means of the spindle gear to the traverse 31, which is displaced between the levers 35, 36. The lever 35 controls the actuation units 40, 41. The actuation unit 40 is formed from the brake disc 14, fixed to the housing by means of the brake 14 or freewheeling, or integrally formed with the latter, and the floating brake shoes 43, 44. The actuation The unit 41 actuates the cable pull 51, which is only partially shown, and alternately controls the freewheels 10, 11 which are arranged between the sun gear 15 and the web 17 carrying the planet wheels 16. The sun gear 15 is dependent on the circuit of the freewheels 10, 11 as well as the web 17 rotationally connected to the crankshaft 8 and connected to the shaft member 64 rotationally connected thereto. Furthermore, the crankshaft 8 of the pulley damper 20 is assigned. About the pulley 63, the gear / actuator unit 24 is integrated into the belt drive 3 of Figure 2. The belt 23 transmits the moments between the starter generator 7 and the crankshaft 8 (FIG. 2).

List of Reference Powertrain

Internal combustion engine

belt drive

friction clutch

transmission

drive wheel

starter generator

crankshaft

rotor

freewheel

planetary gear

ring gear

brake

sun

planet

web

accessory

air compressor

Pulley damper

motor housing

idler

belt

Transmission ZAktoreinheit

Hebelaktor

switching device

baseplate

casing

tilting joint

electric motor

traverse

spindle gear role

role

lever

Energy storage lever point lever arm

Actuator Actuator Brake Disc Brake Shoes Brake Shoes Stop

attack

Recording slider energy storage stop cable

rope

Clamp body sprag cage ramp

ramp

Inner star Lever arm Energy storage Energy storage Stop Energy storage Pulley Shaft part

Claims

claims

1 . Belt drive (3) of a drive train (1) of a motor vehicle with a planetary gear (12) switching a transmission between a starter generator (7) and an internal combustion engine (2) to a ring gear (13) which can be connected to the housing by means of a brake (14) Crankshaft (8) of the internal combustion engine (2) of the drive train (1) connected web (17) with circumferentially disposed planet gears (16) and one with a rotor (9) of the starter generator (7) and at least one auxiliary unit (18) rotationally connected sun gear (15) and a switching device (26) to control a torque direction between the rotor (9) and crankshaft (8), characterized in that the brake (14) by a first actuating unit (40) and the switching device (26) operated by a second actuating unit (41) and a common actuation of both actuating units (40, 41) by means of a single lever actuator (25) is provided.

2. belt drive (3) according to claim 1, characterized in that the lever actuator (25) arranged by means of a tilting joint (29) on a motor housing (21) of the internal combustion engine (2), a first lever (36) forming the housing (28) is, on which one of an electric motor (30) radially displaced traverse (31) between the first lever (36) and a second, to a one of an energy storage (37) set lever point (38) rotatable lever (35) is displaced, and a lever arm (39) of the second lever (35) displaced as a result of the displacement of the traverse (31) is acted upon by the actuating units (40, 41).

3. belt drive (3) according to claim 2, characterized in that the lever actuator (25) against a housing fixedly mounted base plate (27) by means of the tilting joint (29) is tiltably received.

4. belt drive (3) according to one of claims 1 to 3, characterized in that the first actuating unit (40) two on both sides of a brake disc (42) arranged on each one lever (35, 36) abutting brake shoes (43, 44) contains, wherein the brake shoes (43, 44) in displaced traverse (31) against the action of at least between the brake shoes (43, 44) and the motor housing (21) or base plate (27) effectively supporting energy storage (59, 60) Braze brake disc (42) between them.

5. belt drive (3) according to claim 4, characterized in that the brake shoes (43, 44) floating and / or querkraftabstützend on the base plate (27) are added. Belt drive (3) according to any one of claims 1 to 5, characterized in that the second actuating unit (41) by means of a between the first and second levers (35, 36) arranged energy storage device (49) axially biased slide (48), the kinematically effectively actuates the switching device (26).

Belt drive according to claim 6, characterized in that the switching device (26) is a dog clutch.

Belt drive (3) according to claim 6, characterized in that the switching device (26) two alternately switchable freewheels (10, 11) with a one on an inner star (57) displaceable clamping body (53) containing clamping body cage (54) along the Ramps (55, 56) of the inner star (57) of the slider (48) is displaceable, is formed.

Belt drive (3) according to one of claims 6 to 8, characterized in that a cable pull (51) is effectively provided between slide (48) and switching device (26).

Belt drive (3) according to one of claims 1 to 9, characterized in that in a zero position of the lever actuator (25) a torque direction with a Momen- tenfluss from the starter generator (7) to the crankshaft (8) connected and the brake (14) is opened ,