HYBRID DRIVE MODULE FOR A MOTOR VEHICLE

Description

[0001] The invention relates to a hybrid drive module for a motor vehicle. The hybrid drive module can be an integral component of a motor vehicle transmission or be designed as a standalone unit with at least one interface to a motor vehicle transmission. The invention further relates to a drive train for a motor vehicle with such a hybrid drive module.

[0002] Patent application DE 10 2009 020 672 A1 describes a power transmission and drive unit for use in a hybrid system, comprising an electric machine, a clutch device for separating a power flow between a working machine and the rotor of the electric machine, a torque converter connected to the rotor, and a device for at least partially bypassing the hydrodynamic power branch of the torque converter. Various configurations of the torque converter and the actuation of the bypass device are described, in particular a two-channel design and a three-channel design. In a two-channel design, in contrast to a three-channel design, no separate pressure chamber is provided for actuating the bypass device. However, a specific structural design of the power transmission and drive unit with a three-channel design of the torque converter is not disclosed.

[0003] Patent application DE 10 2011 109 702 A1 describes a torque converter with a one-piece housing element that forms a disk carrier of a torque converter lockup clutch and a disk carrier of a separating clutch. Furthermore, the housing element, together with an actuating piston, forms a pressure chamber for actuating the torque converter lockup clutch and the separating clutch. Both the torque converter lockup clutch and the separating clutch are enclosed by the one-piece housing element. The disclosure is limited to line drawings; a specific structural design is not described.

[0004] DE 11 2012 000 391 T5 describes a vehicle drive device with an electric motor and a torque converter. The torque converter has an engagement device configured to connect the pump wheel and the turbine rotor of the torque converter. Furthermore, a further engagement device is provided, configured to connect an internal combustion engine to the electric motor. An inner disk carrier of the further engagement device is arranged axially between an actuating piston of the further engagement device and a housing of the torque converter.

[0005] DE 11 2009 001 077 T5 describes a vehicle drive device with an electric motor and a torque converter. A torque converter lock-up clutch and an engine power cut-off clutch are arranged within a housing of the torque converter.

[0006] DE 10 2009 022 275 A1 describes a drive train for a hybrid system with a first drive motor and a second drive motor, which can be connected to a transmission via a torque converter. A clutch device is provided between the first drive motor and the torque converter, which is actuated by a pressure-medium-actuated actuating device. Furthermore, means for transmitting a predefined minimum torque are provided, which act before the required actuating pressure of the actuating device is built up.

[0007] It is now an object of the invention to further develop the designs known in the prior art in order to provide a hybrid drive module with a structure that is as cost-effective and compact as possible.

[0008] The problem is solved by the features of patent claim 1. Advantageous embodiments emerge from the subclaims, the description and the figures.

[0009] A hybrid drive module for a motor vehicle is proposed, comprising an input shaft, an electric motor with a non-rotatable stator and a rotatable rotor, a separating clutch in the power flow between the input shaft and the rotor, and a torque converter whose housing is non-rotatably connected to the rotor. The torque converter has a lock-up clutch arranged within its housing, which is configured to bridge the hydrodynamic path of the torque converter, i.e., to mechanically connect the pump impeller and turbine impeller of the torque converter.

[0010] The separating clutch is actuated by pressurizing a first pressure chamber via a first piston in the closing direction. In contrast to the embodiment according to DE 10 2011 109 702 A1, the first pressure chamber is located outside the torque converter housing. The lock-up clutch is actuated by pressurizing a second pressure chamber via a second piston in the closing direction. The second pressure chamber is provided exclusively for actuating the lock-up clutch and is arranged within the torque converter housing. In other words, the hybrid drive module according to the present invention uses a torque converter with at least three connecting lines. The at least three connecting lines are structured as follows: an oil inlet channel for the torus chamber of the torque converter, an oil outlet channel for the torus chamber of the torque converter, and an oil channel for supplying pressure to the second pressure chamber.Optionally, a fourth connecting line can be provided to supply a separate pressure equalization chamber of the lock-up clutch.

[0011] According to the invention, both the first pressure chamber and the second pressure chamber are delimited, at least in sections, by the housing of the torque converter. While this is undoubtedly the case for the first pressure chamber in the solution according to DE 10 2009 020 672 A1, such an arrangement of the second pressure chamber does not directly and clearly follow. Fig. 5of the aforementioned publication. The torque converter housing directly separates the first pressure chamber from the second pressure chamber. In other words, a section of the torque converter housing forms a boundary for both the first pressure chamber and the second pressure chamber. Such a design of the two pressure chambers utilizes existing, already present components, so that the number of parts of the hybrid drive module according to the invention can be kept low.

[0012] A first piston for actuating the separating clutch is assigned to the first pressure chamber. Similarly, a piston for actuating the lock-up clutch is assigned to the second pressure chamber. The effective area of ​​the first piston is smaller than the effective area of ​​the second piston. This is particularly advantageous when used with a three-channel torque converter, since the second pressure chamber acts against the pressure present in the torus chamber of the torque converter. The first pressure chamber typically acts against a relatively lower lubrication pressure.

[0013] The first pressure chamber and the second pressure chamber are arranged radially one above the other, at least in sections. In other words, the two pressure chambers are arranged radially nested. The resulting geometry of the torque converter housing is stiffer than a straight housing wall, so that the actuating pressure for the separating clutch or the lock-up clutch leads to a lesser deformation of the torque converter housing. The second piston surrounds the first pressure chamber, at least in sections. In other words, sections of the second piston are arranged both radially outside and radially inside the first pressure chamber.

[0014] According to a preferred embodiment, the torque converter housing has an undercut, i.e., a region with axially reduced dimensions relative to the overall length of the torque converter housing. This undercut is designed to guide the first piston. The undercut does not necessarily have to guide the first piston alone; rather, other surfaces can also be provided to guide the first piston. Such a design utilizes an existing, already present component to guide the first piston, so that the number of parts of the hybrid drive module according to the invention can be kept low.

[0015] The housing of the torque converter is preferably connected to a hub in a rotationally fixed manner. The hub preferably serves to rotatably support the torque converter and is designed, for example, as a turned part, while the torque converter housing is usually a sheet metal construction. The hub preferably has at least one fluid channel for supplying fluid to the first pressure chamber. The fluid channel can be designed, for example, as a bore. The hub preferably also has a second fluid channel for supplying fluid to the second pressure chamber, or at least partially delimits such a channel. The hub is therefore involved in forming the fluid supply to at least one of the pressure chambers. Such channels are particularly easy to manufacture in a turned part, for example by means of bores. The hub is therefore particularly suitable for this purpose.

[0016] According to a preferred embodiment, both the separating clutch and the lock-up clutch are designed as wet-running multi-plate clutches. An outer plate carrier of the separating clutch is connected in a rotationally fixed manner to the torque converter housing. This enables a particularly compact design of the hybrid drive module. Preferably, the outer plate carrier is riveted to the torque converter housing. The riveted connection can be arranged within the first pressure chamber. The riveted connection can be arranged in a region of the torque converter housing that delimits the second pressure chamber.

[0017] The hybrid drive module is preferably an integral component of a motor vehicle transmission. The single- or multi-part housing of the hybrid drive module accommodates, for example, planetary gear sets and shifting elements, by means of which a plurality of gears can be shifted between an input shaft and an output shaft of the transmission. Instead of the planetary gear sets and shifting elements, the transmission can also comprise a friction gear with movable gears, by means of which the gear ratio between the input shaft and output shaft can be continuously varied. The transmission can also be designed as a single- or dual-clutch transmission, which uses switchable spur gear pairs to generate gears.

[0018] Alternatively, the hybrid drive module can be designed as a standalone unit with an interface to a motor vehicle transmission. The hybrid drive module can be detached from the transmission.

[0019] The hybrid drive module can be part of a motor vehicle's drivetrain. The electric motor of the hybrid drive module can be used to drive the motor vehicle and / or to start an internal combustion engine of the drivetrain.

[0020] Exemplary embodiments are described in detail below with reference to the attached figures. They show: Fig. 1 and Fig. 2 a sectional view of various embodiments of a hybrid drive module; Fig. 3 a sectional view of an embodiment of a hybrid drive module according to the invention; and Fig. 4 and Fig. 5 one drive train each for a motor vehicle.

[0021] Fig. 1shows a sectional view of a hybrid drive module 1 according to a first exemplary embodiment. The hybrid drive module 1 has an input shaft IN, an electric machine with a rotationally fixed stator S and a rotatable rotor R, a separating clutch K0 in the form of a multi-plate clutch, and a torque converter TC. By closing the separating clutch K0, the input shaft IN can be connected to the rotor R, which is connected to a housing TCG of the torque converter TC. For this purpose, the input shaft IN is connected to an inner disk carrier of the separating clutch K0, while the rotor R is connected to an outer disk carrier of the separating clutch K0. The torque converter TC has a lock-up clutch WK arranged within the housing TCG, which is designed to connect the pump impeller and turbine impeller of the torque converter TC to one another, thus mechanically short-circuiting the hydrodynamic path of the torque converter TC.The lock-up clutch WK is designed as a multi-plate clutch.

[0022] Both the separating clutch K0 and the lock-up clutch WK are hydraulically actuated. A first pressure chamber DK1 is provided for actuating the separating clutch K0, which is located outside the housing TCG. If the pressure in the first pressure chamber DK1 is increased, a first piston K0K is moved against the force of a Fig. 1 A return spring (not shown) displaces the clutch toward a plate pack of the separating clutch K0. The separating clutch K0 can thus be actuated in the closing direction by applying pressure to the first pressure chamber DK1. On the end face of the first piston K0K facing away from the first pressure chamber DK1, a pressure compensation chamber is provided, which is delimited in the axial direction by a baffle plate.

[0023] To actuate the lock-up clutch WK, a second pressure chamber DK2 is provided, which is located within the housing TCG. If the pressure in the second pressure chamber DK2 increases, a second piston WKK is moved against the force of a Fig. 1A further return spring (not shown) is displaced in the direction of a plate pack of the lock-up clutch WK. The lock-up clutch WK can thus be actuated in the closing direction by applying pressure to the second pressure chamber DK2. No separate pressure equalization chamber is provided on the end face of the second piston WKK facing away from the second pressure chamber DK2. Rather, the pressure in the second pressure chamber DK2 acts against the pressure present in the torus chamber of the torque converter TC. The effective area of ​​the second piston WKK is larger than the effective area of ​​the first piston K0K. The "effective area" here refers to the cross-sectional area of ​​the pistons K0K, WKK, on ​​which the pressure in the respective pressure chamber DK1, DK2 acts.

[0024] The first and second pressure chambers DK1, DK2 are delimited, at least in part, by the housing TCG. In other words, the pressure in the pressure chambers DK1, DK2 is directly supported by the housing TCG. The housing TCG directly separates the first pressure chamber DK1 from the second pressure chamber DK2.

[0025] The housing TCG is connected to a hub N in a rotationally fixed manner, for example, by means of a welded joint. The hub N can be manufactured, for example, by machining, while the housing TCG is usually manufactured by forming. The hub N has a first fluid channel FK1 in the form of a bore, which is provided for supplying fluid to the first pressure chamber DK1. The hub N further has a second fluid channel FK2, which is provided for supplying fluid to the second pressure chamber DK2.

[0026] The outer disc carrier of the K0 separating clutch is connected to the TCG housing by means of a riveted joint. The riveted joint, or rivet head, is located within the first pressure chamber DK1.

[0027] Fig. 2 shows a sectional view of a hybrid drive module 1 according to a second embodiment, which essentially corresponds to the Fig. 1 The torque converter TC now has four hydraulic connections, allowing fluid to be supplied to a pressure compensation chamber associated with the lock-up clutch WK. A third fluid channel FK3 is provided in the hub N to supply this pressure compensation chamber.

[0028] Fig. 3shows a sectional view of a hybrid drive module 1 according to a third exemplary embodiment. In contrast to the other exemplary embodiments, the housing TCG has an undercut TCH in the area of ​​the hub N. The two pressure chambers DK1, DK2 are arranged radially one above the other in sections. In other words, sections of both pressure chambers DK1, DK2 are arranged in a common plane which is perpendicular to the axis of rotation of the assembly consisting of rotor R and housing TCG. The second piston WKK surrounds the first pressure chamber DK1 in the radial direction. This configuration stiffens both the housing TCG and the two pistons K0K, WKK, so that pressure in the pressure chambers DK1, DK2 leads to a reduced deformation of the housing TCG or the pistons K0K, WKK.

[0029] The torque converter TC used in the third exemplary embodiment of the hybrid drive module 1 has three hydraulic connections. The lock-up clutch WK is therefore not assigned its own pressure equalization chamber. The pressure in the second pressure chamber DK2 thus counteracts the pressure present in the torus chamber of the torque converter TC. The fluid supply to the second pressure chamber DK2 is via the second fluid channel FK2, which is partially delimited by the hub N.

[0030] Fig. 4shows a drive train of a motor vehicle. The drive train has an internal combustion engine VM, the hybrid drive module 1, and a transmission AT. The hybrid drive module 1 and the transmission AT are separate units with at least one interface via which the hybrid drive module 1 and the transmission AT can be connected to one another. The hydraulic supply to the hybrid drive module 1 is preferably provided via a hydraulic system of the transmission AT. On the output side, the transmission AT is connected to a differential gear AG, for example, via a cardan shaft. The differential gear AG distributes the power applied to an output shaft of the transmission AT to drive wheels DW of the motor vehicle.

[0031] Fig. 5 shows a drive train of a motor vehicle, which essentially corresponds to the Fig. 4The hybrid drive module 1 and the AT transmission now form a common unit. In other words, the hybrid drive module 1 is an integral part of the AT transmission.

[0032] The Fig. 4 and Fig. 5 The drivetrains shown are merely examples. Instead of the illustrated design with a drivetrain aligned longitudinally to the direction of travel of the motor vehicle, use in a drivetrain aligned transversely to the direction of travel is also conceivable. The differential gear AG can be integrated into the transmission G. The drivetrain with the hybrid drive module 1 is also suitable for all-wheel drive applications. Reference symbol

[0033] 1Hybrid drive module INSupply shaft NNub SStator RRotor K0Disconnect clutch K0First piston DK1First pressure chamber FK1First fluid channel TCTorque converter TCGHousing TCHUndercut WKLock-up clutch WKKZSecond piston DK2Second pressure chamber FK2Second fluid channel FK3Third fluid channel VMCombustion engine ATGearbox AGDifferential gear DWDrive gear

Claims

1. Hybrid drive module (1) for a motor vehicle, wherein the hybrid drive module (1) has an input shaft (IN), an electric machine with a rotationally fixed stator (S) and a rotatable rotor (R), a separating clutch (K0) in the force flow between the input shaft (IN) and the rotor (R), and also a torque converter (TC), the housing (TCG) of which is connected in a rotationally fixed manner to the rotor (R), - wherein the separating clutch (K0) can be actuated in the closing direction by applying pressure to a first pressure chamber (DK1) via a first piston (K0K), wherein the first pressure chamber (DK1) is arranged outside the housing (TCG) of the torque converter (TC), - wherein the torque converter (TC) has a bridging clutch (WK) which is arranged inside the housing (TCG) of the torque converter (TC) and is designed to bridge a hydrodynamic path of the torque converter (TC), - wherein the bridging clutch (WK) can be actuated in the closing direction by applying pressure to a second pressure chamber (DK2) by means of a second piston (WKK), wherein the second pressure chamber (DK2) is intended solely for actuating the bridging clutch (WK) and is arranged inside the housing (TCG) of the torque converter (TC), wherein both the first pressure chamber (DK1) and the second pressure chamber (DK2) are delimited by the housing (TCG) of the torque converter (TC) at least in portions, wherein the housing (TCG) of the torque converter (TC) directly separates the first pressure chamber (DK1) from the second pressure chamber (DK2), characterized in that the effective area of the first piston (KOK) is smaller than the effective area of the second piston (WKK), wherein the first pressure chamber (DK1) and the second pressure chamber (DK2) are arranged radially one above the other at least in portions, and wherein the second piston (WKK) surrounds the first pressure chamber (DK1) in portions.

2. Hybrid drive module (1) according to Claim 1, characterized in that the housing (TCG) of the torque converter (TC) has an undercut (TCH) which serves to guide the first piston (K0K).

3. Hybrid drive module (1) according to either of the preceding claims, characterized in that the housing (TCG) of the torque converter (TC) is connected in a rotationally fixed manner to a hub (N) which has a first fluid duct (FK1) for supplying fluid to the first pressure chamber (DK1).

4. Hybrid drive module (1) according to Claim 3, characterized in that the hub (N) has a second fluid duct (FK2) for supplying fluid to the second pressure chamber (DK2) or delimits the second fluid duct at least in portions.

5. Hybrid drive module (1) according to any of the preceding claims, characterized in that the separating clutch (K0) and the bridging clutch (WK) are in the form of multi-plate clutches, wherein an outer plate carrier of the separating clutch (K0) is connected in a rotationally fixed manner to the housing (TCG) of the torque converter (TC).

6. Hybrid drive module (1) according to Claim 5, characterized in that the outer plate carrier of the separating clutch (K0) is riveted to the housing (TCG) of the torque converter (TC).

7. Hybrid drive module (1) according to Claim 6, characterized in that the rivet connection between the outer plate carrier of the separating clutch (K0) and the housing (TCG) of the torque converter (TC) is arranged inside the first pressure chamber (DK1).

8. Hybrid drive module (1) according to Claim 6 or Claim 7, characterized in that the rivet connection between the outer plate carrier of the separating clutch (K0) and the housing (TCG) of the torque converter (TC) is arranged in a portion of the housing (TCG) that delimits the second pressure chamber (DK2).

9. Hybrid drive module (1) according to any of the preceding claims, characterized in that the hybrid drive module (1) is either an integral constituent part of a motor vehicle transmission (AT) or is in the form of an independent unit with at least one interface to the motor vehicle transmission (AT).

10. Drive train for a motor vehicle, characterized by a hybrid drive module (1) according to any of the preceding claims.