DE102018200569B3 - Hybrid drive module for a motor vehicle - Google Patents

Abstract

The invention relates to a hybrid drive module (1) for a motor vehicle which has a housing (GG), an electric machine with a rotatable rotor (R) and a stator (S) which is rotationally fixed relative to the housing (GG) and a torque converter (TC), wherein the rotor (R) is disposed on a rotor carrier (RT) fixedly connected to a hub (N), the hub (N) being connected via a rotationally fixed connection to a converter housing (TCH) of the torque converter (TC). The hybrid drive module (1) is characterized in that a pre-centering unit (Z) for positioning the hub (N) is provided on a bearing plate (LS) attached to the housing (GG), and that the pre-centering unit (Z) has a clear inside diameter (DV). which satisfies the condition DN <DV <[DN + 2 * GSR], wherein DN for the outer diameter of the hub (N), DV for the inner diameter of the pre-centering unit (Z) and GSR for the air gap between the stator (S) and Rotor (R) stands. Furthermore, the invention relates to a drive train for a motor vehicle with such a hybrid drive module (1).

Description

The invention relates to a hybrid drive module for a motor vehicle. The hybrid drive module may be an integral part of a motor vehicle automatic transmission, or be designed as a separate unit with at least one interface to a motor vehicle automatic transmission. The invention further relates to a drive train for a motor vehicle with such a hybrid drive module.

The patent US 6,777,837 B2 describes a hybrid drive unit having an electric machine and a torque converter within a housing. A rotor of the electric machine is rotatably mounted on a bearing plate on a bearing plate, wherein the rotor is rotatably connected via a spline with a central part. The central part is connected via a welded connection to a front cover of the torque converter. With such a construction, it is not ensured that the electric machine and the torque converter have the same rotation axis. As a result, unwanted vibrations can occur in the motor vehicle drive train.

The patent US Pat. No. 6,478,101 B1 also describes a hybrid drive unit having an electric machine and a torque converter within a housing. A rotor of the electric machine is mounted via a centering seat in the crankshaft of an internal combustion engine, to which the hybrid drive unit can be connected. The rotor is bolted to weld nuts attached to a front cover of the torque converter. The centering seat is convex to reduce the transmission of torsional vibrations from the engine to the rotor. However, this allows a tilting movement between the rotor and the stator of the electric machine, whereby unwanted vibrations can occur in the motor vehicle drive train.

The patent application DE 10 2006 034 945 A1 describes a drive assembly for a hybrid vehicle having an electric machine and a torque converter. A rotor of the electric machine is connected to a hub, which is connected to a clutch output shaft, which is connected via a spline with a converter housing of the torque converter. The spline can cause a misalignment of the torque converter relative to the rotor. Due to the resulting imbalance unwanted vibrations can occur in the motor vehicle powertrain.

Furthermore, from the prior art, the writings DE 10 2005 053 887 A1 . DE 10 2009 059 944 A1 such as DE 10 2014 202 279 A1 known.

It is therefore an object of the invention to provide a hybrid drive module, which allows the most accurate storage and centering of rotor and torque converter to prevent vibration excitation.

The object is solved by the features of claim 1. Advantageous embodiments will become apparent from the dependent claims, the description and from the figure.

It is proposed a hybrid drive module for a motor vehicle, which has a housing, an electric machine and a torque converter. The electric machine has a rotatable rotor and a stator rotatable relative to the housing. An air gap is provided between the rotor and the stator. The rotor is arranged on a rotor carrier, which is rotatably connected to a hub. The hub is connected via a rotationally fixed connection with a converter housing of the torque converter.

According to the invention, a pre-centering unit for positioning the hub is provided on a bearing plate fastened to the housing, and the pre-centering unit has a clear internal diameter which satisfies the following condition: $$\text{DN}<\text{DV}<\left[\text{DN}+2*\text{GSR}\right]$$

This is DN for the outer diameter of the hub, DV for the clear inside diameter of the pre-centering unit and GSR for the air gap between stator and rotor. The clear inner diameter of the pre-centering unit is aligned coaxially to a rotational axis of the electric machine. This design ensures that a positioning of the hub is provided by the Vorzentriereinheit, in which after lifting or lifting the hub of the Vorzentriereinheit is possible or during assembly so that the hub is freely rotatable. At the same time, the pre-centering unit prevents the rotor and the stator from coming into contact, thereby preventing damage to the electric machine. In other words, the pre-centering unit forms a temporary support of the hub during transport and storage as well as an assembly aid to prevent damage to the electrical machine. In particular, for the clear inner diameter, a range of DV <= [DN + GSR], ie smaller or smaller equal to the sum of the outer diameter of the hub and the air gap of the electric machine, preferably because this the range of motion of the hub during transport and storage is reduced and at the same time the contact between rotor and stator can be avoided even with elastic deformation of the material of Vorzentriereinheit and / or hub.

In embodiments of the invention, the rotationally fixed connection of the hub with a converter housing of the torque converter via a rivet connection or a screw connection is formed. In other words, the converter housing and the rotor carrier are fixedly connected to the hub, whereby a same axis of rotation of rotor and torque converter is ensured. Due to the radial and axial support of the hub on the bearing plate thus a precise storage of both the rotor and the converter housing can be achieved.

In embodiments of the invention, the hub has a torque transmitting interface to a first half of an offset compensation element. A second half of the offset compensation element can be connected torque-transmitting to the crankshaft of the internal combustion engine, optionally via an intermediate element. The offset compensation element is adapted to compensate for both a radial offset between the axes of rotation of its two halves and an axial offset between its two halves. The use of such an offset compensation element decouples the bearing and support of the hub, torque converter and rotor carrier assembly from the crankshaft. This further reduces the susceptibility of the hybrid drive module to vibration.

Preferably, the first half of the offset compensation element on a front side on a toothing. This toothing is in engagement with a toothing, which is formed on an end face of the hub, so that the first half of the offset compensation element is connected to transmit torque to the hub. Such a tooth pairing is also referred to as Hirth toothing, and enables a reliable centering between the components connected to the toothing. Preferably, the toothing between the hub and the offset compensation element is biased by a screw. Thereby, the torque transmission capability of the teeth can be increased.

Further preferred embodiments of the invention are characterized in that a crankshaft journal for centering the crankshaft is formed by a screw head of the screw. This ensures that the axis of rotation of the hub and the torque converter are aligned with the axis of rotation of the crankshaft, whereby imbalances and thus reduces wear and a smooth running behavior is achieved. Furthermore, this results in a bearing of the hub, which can reduce the number of bearings and thus avoids any associated overdetermined storage of the hub.

In further embodiments according to the invention, hybrid drive modules are characterized in that a crankshaft journal for centering the crankshaft is formed on the hub or the first half of the offset compensation element. By such embodiments can be ensured that the axis of rotation of the hub and the torque converter is aligned with the axis of rotation of the crankshaft, whereby imbalances and thus reduces wear and a smooth running behavior can be achieved. Furthermore, this results in a bearing of the hub, which can reduce the number of bearings and thus avoids any associated overdetermined storage of the hub.

Preferably, the second half of the offset compensation element can be connected via a flexplate to the crankshaft of the internal combustion engine. A flexplate is understood to mean a plate-shaped torque-transmitting device which is flexible enough to compensate for slight misalignments of the components to be connected.

The offset compensation element may be formed by a composite comprising a torsional vibration damper and a torsional vibration damper. The torsional vibration damper is designed in addition to its function for damping torsional vibrations to compensate for a radial offset. The torsional vibration damper is in addition to its function for the at least partial eradication of torsional vibrations adapted to compensate for an axial offset. In such an embodiment of the offset compensation element, the torque-transmitting interface of the offset compensation element to the hub can be designed as a spline. Preferably, the torsional vibration damper is disposed between the torsional vibration damper and the hub.

Embodiments of a hybrid drive module according to the invention are characterized in that the pre-centering unit is formed from a plastic, a material for sliding bearings or another material softer relative to the hub. As a result, the assembly of the hybrid drive module is facilitated and at the same time it is ensured that the hub is not damaged by a contact with the pre-centering unit.

According to a preferred embodiment, the rotor carrier is bolted to the hub, riveted or welded. Such a two-part construction of the hub and rotor carrier assembly facilitates mechanical machining of the hub.

According to a preferred embodiment, the converter housing is rotatably mounted via a second bearing on a second bearing plate of the hybrid drive module. The second bearing is preferably located at an axial end of the torque converter, which faces the interface with the hub. As a result, a particularly broad bearing base of the composite torque converter, hub and rotor arm including rotor and crankshaft can be achieved.

Preferably, the stator is attached directly to the bearing plate. Since the rotor is at least temporarily supported or positioned via the rotor carrier, hub and pre-centering unit on the same bearing plate, a short tolerance chain between rotor and stator results. As a result, the air gap between the rotor and stator or the coaxial alignment of the pre-centering unit and the axis of rotation of the rotor is particularly accurately adjustable, and is subject to only small tolerances.

According to a preferred embodiment, a clutch is arranged within the converter housing, wherein the converter housing can be connected to a turbine wheel of the torque converter by closing this clutch. Since an impeller of the torque converter is usually non-rotatably connected to the converter housing, the closing of this clutch leads to a bridging of the torque converter. Within the converter housing, a torsional vibration damper is further arranged, which acts between the clutch and an output hub of the torque converter connected to the turbine wheel. By such a configuration, torsional vibrations can be reduced at the hub when the clutch is closed. Preferably, a torsional vibration damper is further provided, which is arranged within the converter housing and acts between the turbine wheel and the output hub of the torque converter. By such an arrangement, torsional vibrations on the output hub can be further reduced, especially in the area of action of the torsional vibration damper. In addition, a further torsional vibration damper may be provided, which is arranged within the converter housing and acts between the clutch and the torsional vibration damper. Such an arrangement also reduces the torsional vibrations occurring at the output hub.

Preferably, the hybrid drive module is an integral part of a motor vehicle automatic transmission. The torque converter serves as a starting element of a motor vehicle equipped with the automatic transmission. The one- or multi-part housing of the hybrid drive module accommodates planetary gear sets and switching elements by means of which a plurality of gears between a drive shaft and an output shaft of the automatic transmission can be shifted. The drive shaft is connected to the output hub of the torque converter.

Alternatively, the hybrid drive module may be formed as a stand-alone unit with an interface to a motor vehicle automatic transmission. The hybrid drive module is detachable from the automatic transmission.

The hybrid drive module may be part of a drive train of a motor vehicle. The electric machine of the hybrid drive module can be provided for driving the motor vehicle and / or for starting an internal combustion engine of the drive train.

• 1 ein Hybridantriebsmodul gemäß einem Ausführungsbeispiel;
• 2 und 3 je einen Antriebsstrang eines Kraftfahrzeugs.

Embodiments of the invention are described in detail below with reference to the accompanying figure. Show it:

• 1 a hybrid drive module according to an embodiment;
• 2 and 3 each a drive train of a motor vehicle.

1 shows a hybrid drive module 1 according to an embodiment. The hybrid drive module 1 includes a housing GG , inside of which is an electric machine with one opposite the housing GG non-rotating stator S and a rotatable rotor R is arranged. The hybrid drive module 1 has a torque converter TC on. An impeller P of the torque converter TC is with a converter housing TCH of the torque converter TC firmly connected. A stator L of the torque converter TC is rotatably supported via a freewheel in one direction of rotation. A turbine wheel T of the torque converter TC is via a torsional vibration damper TI with an output hub TA of the torque converter TC connected. The hybrid drive module 1 also has an additional, optional torsional vibration damper TD3 on. The torsional vibration damper TD3 is within the hiking enclosure TCH , between the clutch WK and the torsional vibration damper TI arranged. The output hub TA is with a drive shaft LV1 connected to an automatic transmission, not shown. Inside the converter housing TCH is also a clutch WK arranged. By closing the clutch WK is the converter housing TCH with one half of a torsional vibration damper TD2 connectable. Another half of the torsional vibration damper TD2 is with the output hub TA connected.

The rotor R the electric machine is on a rotor carrier RT arranged, which via a screw with a hub N is firmly connected. The hub N is up to the assembly with the crankshaft KW via the pre-centering unit Z rotatably mounted or positioned. The pre-centering unit Z is formed as an annular member, and is adapted to the hub N at their clear inside diameter DV to support in the radial direction. To simplify the assembly of the hybrid drive module, the pre-centering unit has Z at least on one side, in 1 on the right the rotor arm RT facing side, an inlet slope in the form of a phase and / or a radius, which the clear inner diameter DV extended. With the outer circumference is the pre-centering unit Z on a bearing plate LS supported or connected with it. The bearing plate LS is on the case GG attached, and also serves for the direct attachment of the stator S the electric machine. The bearing plate LS thus serves as a stator.

The bearing plate LS separates a wet room NO of the hybrid drive module 1 from a drying room TR , The sealing of the wet room NO to the drying room TR via a sealing ring DR which is immediately next to the pre-centering unit Z is arranged.

The hub N has a torque-transmitting offset compensation element VA on which a first half VA1 and a second half VA2 includes. The offset compensation element VA is in the drying room TR of the hybrid drive module 1 arranged. The offset compensation element VA is configured to have both a radial offset and an axial offset between its two halves VA1 . VA2 compensate. The first half VA1 is with the hub N connected. This is indicated by the hub N a torque transmitting interface, which as a toothing NZ is trained. The gearing NZ is located at one end of the hub N , At the first half VA1 is a gearing VAZ formed, which with the toothing NZ is engaged. The thus axially aligned gear pairing is used for torque transmission from the first half VA1 to the hub N and for centering these two components. The second half VA2 is via a flexplate, not shown, to a crankshaft WK connected. The second half VA2 is connected via a screw connection with the Flexplate, which via a further screw connection with the crankshaft KW connected is.

The hub N is via a riveted joint RI with the converter housing TCH of the torque converter TC rotatably connected. The rivet connection is designed as a through-rivet connection, so there are no through-holes in the converter housing TCH required are. Through the riveted joint RI Ensures that the composite hub N , Rotor carrier RT , Rotor R and converter housing TCH have the same axis of rotation. This composite is before assembly, ie during transport and storage, via the pre-centering unit Z or after assembly via the crankshaft KW and a second camp L2 stored. The second camp L2 is on a second end shield LS2 of the hybrid drive module 1 supported. The second camp L2 is designed as a needle bearing. The second end shield LS2 is with the case GG connected. The support of the stator L also takes place via the second end shield LS2 ,

In the illustrated embodiment, an optional valve is also shown, which is designed as a spring-loaded seat valve. The converter housing TCH of the torque converter TC has an opening A on, in which a sleeve of the valve is inserted. The opening A is closed by the sleeve of the valve. In the sleeve, a spring is supported, which presses a piston in the direction of a valve seat. The valve seat is held by the sleeve. The inside of the torque converter TC acting pressure acts on the piston. If the pressure difference between the interior and the wet space is large enough, the piston is displaced against the force of the spring so that the piston lifts off from the valve seat. This allows hydraulic fluid from the interior of the torque converter TC in the wet room NO stream. The hydraulic fluid emerging from the interior reaches a winding head of the electric machine and can cool it.

2 shows a drive train of a motor vehicle. The drive train has an internal combustion engine VM , the hybrid drive module 1 as well as an automatic transmission AT on. Hybrid drive module 1 and automatic transmission AT are separate units with at least one interface through which the hybrid drive module 1 and the automatic transmission AT can be connected to each other. A hydraulic supply to the hybrid drive module 1 preferably takes place via a hydraulic system of the automatic transmission AT , On the output side is the automatic transmission AT with a differential gear AG connected, for example via a propeller shaft. By means of the differential gear AG is the on an output shaft of the automatic transmission AT applied power on drive wheels DW of the motor vehicle distributed.

3 shows a drive train of a motor vehicle, which substantially the in 2 shown drive train corresponds. The hybrid drive module 1 and the automatic transmission AT now form a common unit. In other words, the hybrid drive module 1 integral part of the automatic transmission AT ,

In the 2 and 3 shown drive trains are to be considered as exemplary only. Instead of the illustrated construction with the drive train aligned longitudinally to the direction of travel of the motor vehicle, use in a drive train oriented transversely to the direction of travel is also conceivable. The differential gear AG can be integrated in the transmission G. The powertrain with the hybrid drive module 1 is also suitable for four-wheel application.

LIST OF REFERENCE NUMBERS

1

Hybrid drive module

GG

casing

S

stator

R

rotor

RT

rotorarm

GSR

air gap

NO

wet room

TR

drying room

DR

seal

N

hub

NZ

gearing

LS

end shield

Z

Vorzentriereinheit

L2

Second camp

LS2

Second bearing plate

TC

torque converter

TCH

converter housing

P

impeller

L

stator

T

turbine

WK

clutch

TI

A torsional vibration damper

TD2

torsional vibration damper

TD3

torsional vibration damper

RI

rivet

KW

crankshaft

VM

internal combustion engine

VA

Offset compensation element

VA1

First half

VA2

Second half

VAZ

gearing

SZ

screw

AT

automatic transmission

TA

output hub

LV1

drive shaft

A

opening

AG

differential gear

DW

drive wheel

Claims (15)

Hybrid drive module (1) for a motor vehicle, wherein the hybrid drive module (1) comprises a housing (GG), an electric machine with a rotatable rotor (R) and a relative to the housing (GG) rotationally fixed stator (S), wherein between the rotor (R ) and the stator (S) an air gap (GSR) is provided, and a torque converter (TC), - wherein the rotor (R) on a rotor carrier (RT) is arranged, which is fixedly connected to a hub (N), - Wherein the hub (N) via a rotationally fixed connection to a converter housing (TCH) of the torque converter (TC) is connected, characterized in that on a housing (GG) fixed bearing plate (LS) a pre-centering unit (Z) for positioning the hub (N) is provided, and that the pre-centering unit (Z) has a clear inner diameter (DV), the condition $$\text{DN}<\text{DV}<\left[\text{DN}+2*\text{GSR}\right]$$

where DN is the outer diameter of the hub (N), DV is the inner diameter of the pre-centering unit (Z) and GSR is the air gap between the stator (S) and the rotor (R). Hybrid drive module (1) after Claim 1 , characterized in that the rotationally fixed connection between the hub (N) and converter housing (TCH) is formed by a rivet connection (RI) or a screw connection. Hybrid drive module (1) after Claim 1 or 2 , characterized in that the hub (N) has a torque-transmitting interface to a first half (VA1) of an offset compensation element (VA), wherein a second half (VA2) of the offset compensation element (VA) torque transmitting to a crankshaft (KW) of an internal combustion engine can be connected wherein the offset compensation element (VA) is adapted to both a radial offset and an axial offset between its two halves (VA1, VA2). Hybrid drive module (1) after Claim 3 , characterized in that the first half (VA1) of the offset compensation element (VA) at one end face has a toothing (VAZ) which engages with a toothing (NZ) formed on an end face of the hub (N), so that the first half (VA1) of the offset compensation element (VA) with the hub (N) is transmitted to transmit torque. Hybrid drive module (1) after Claim 4 , characterized in that the toothing (VAZ, NZ) between the hub (N) and the first half (VA1) of the offset compensation element (VA) by means of a screw (SZ) is biased. Hybrid drive module (1) after Claim 5 , characterized in that by a screw head (SZK) of the screw (SZ) is formed a crankshaft journal for centering the crankshaft (KW). Hybrid drive module (1) according to one of Claims 3 to 5 , characterized in that on the hub (N) or the first half (VA1) of the offset compensation element (VA), a crankshaft journal for centering the crankshaft (KW) is formed. Hybrid drive module (1) according to one of Claims 3 to 7 , characterized in that the second half (VA2) of the offset compensation element (VA) via a flexplate to the crankshaft (KW) is connectable. Hybrid drive module (1) according to any one of the preceding claims, characterized in that the pre-centering unit (Z) is formed of a plastic, a material for sliding bearings or other soft against the hub material. Hybrid drive module (1) according to one of the preceding claims, characterized in that the rotor carrier (RT) with the hub (N) is screwed, riveted or welded. Hybrid drive module (1) according to one of the preceding claims, characterized in that the converter housing (TCH) via a second bearing (L2) on a second bearing plate (LS2) of the hybrid drive module (1) is mounted. Hybrid drive module (1) according to one of the preceding claims, characterized in that the stator (S) is attached directly to the bearing plate (LS). Hybrid drive module (1) according to one of the preceding claims, characterized in that a clutch (WK) is arranged within the converter housing (TCH), wherein closing the clutch (WK) the converter housing (TCH) with a turbine wheel (T) of the torque converter ( TC), wherein a torsional vibration damper (TD2) is arranged within the converter housing (TCH) between the clutch (WK) and an output hub (TA) of the torque converter (TC) connected to the turbine wheel (T). Hybrid drive module (1) according to one of the preceding claims, characterized in that the hybrid drive module (1) is either an integral part of a motor vehicle automatic transmission (AT) or is designed as a separate unit with at least one interface to the motor vehicle automatic transmission (AT). Drive train for a motor vehicle, characterized by a hybrid drive module (1) according to one of the preceding claims.

Images