Torque transmission device

Abstract

Torque transmission device (1, 1a, 1b) with a dual-mass flywheel (2, 2a) having an input part (11) rotatably arranged about an axis of rotation (d), which is connected to the crankshaft of an internal combustion engine and forms the primary flywheel mass (12) of the dual-mass flywheel (2), an output part (26) rotatably arranged about the axis of rotation (d) relative to the input part (11) against the action of a spring device (14, 14a, 14b), to which a secondary flywheel mass (13) is assigned, wherein the secondary flywheel mass (13) is formed from a housing (4, 4a, 4b) of the torque converter (3, 3a) and the pump impeller (5) integrated into the housing (4, 4a, 4b), and a hydrodynamic torque converter (3, 3a) with a turbine impeller (6, 6a, 6b), a pump impeller (5) and a converter lock-up clutch (10, 10a, 10b), wherein the converter lock-up clutch (10, 10a, 10b) is arranged on the outer circumference of the turbine wheel (6, 6a, 6b) and the pump wheel (5) and the spring assembly (14,14a) at least overlaps the axial installation space of the turbine wheel (6, 6a, 6b), wherein at least one centrifugal pendulum (23a, 23b) is arranged between the inlet part (11) and the outlet part (26), wherein the centrifugal pendulum (23a, 23b) is arranged axially between the spring assembly (14a, 14b) and the converter lock-up clutch (10a, 10b).

Description

[0001] The invention relates to a torque transmission device comprising a dual-mass flywheel with an input part arranged such that it can rotate about an axis of rotation, an output part arranged such that it can rotate about the axis of rotation relative to the input part against the action of a spring device, and a hydrodynamic torque converter with a turbine wheel, a pump wheel and a converter lock-up clutch.

[0002] Generic torque transmission devices are used, for example, in the drive trains of motor vehicles with an internal combustion engine and, in particular, a transmission designed as an automatic transmission. They generally contain a hydrodynamic torque converter arranged between the internal combustion engine and the automatic transmission as a starting element. To save energy, torque converters contain a torque converter lock-up clutch that bridges the fluid torque transmission at higher speeds. As internal combustion engines are downsized, for example, with cylinder deactivation and a reduction in the number of cylinders, higher inertias and efficient torsional vibration isolation are required on the crankshaft. For this purpose, torque transmission devices that combine a dual-mass flywheel with a hydrodynamic torque converter are known, for example from EP 2 700 846 A1 and WO 2013 / 046006 A1.Due to the axial arrangement of the dual-mass flywheel and the torque converter next to each other, a large installation space is required.

[0003] Further torque converters of this type are disclosed in the publications DE 10 2008 026 426 A1, DE 10 2009 039 996 A1, DE 10 2015 205 886 A1, DE 10 2014 221 573 A1 and DE 10 2012 219 799 A1.

[0004] The object of the invention is to further develop a torque transmission device with axially reduced installation space.

[0005] The object is solved by the subject matter of claim 1. The claims dependent on claim 1 represent advantageous embodiments of the subject matter of claim 1.

[0006] The proposed torque transmission device is intended in particular for a drive train of a motor vehicle with an internal combustion engine, for example, a combustion engine with two to six cylinders, a crankshaft, and a transmission, preferably an automatic transmission with a transmission input shaft. The torque transmission device is arranged between the crankshaft and the transmission input shaft and includes a dual-mass flywheel and a hydrodynamic torque converter with a torque converter lock-up clutch.

[0007] The dual-mass flywheel contains an input part with a primary flywheel mass and is arranged so as to be rotatable about an axis of rotation, and an output part with a secondary flywheel mass and is arranged coaxially to the input part. The input part is connected to the crankshaft of an internal combustion engine and forms the primary flywheel mass of the dual-mass flywheel. The input and output parts can be rotated relative to one another about the axis of rotation, counter to the effect of a spring device. The spring device can contain spring elements arranged over one or more diameters, distributed over the circumference and optionally nested, for example straight, short helical compression springs and / or long arc springs. By arranging the spring elements accordingly, a single- or multi-stage damping effect of the dual-mass flywheel can be achieved. The mass of the torque converter, in particular the housing including the impeller, serves as the secondary flywheel mass.In particular, the spring elements designed as arc springs can be housed in an annular chamber formed by the input part. The input part can be made of sheet metal, i.e., of several interconnected sheet metal parts, and can be directly connected to the crankshaft.

[0008] The torque converter contains a housing arranged coaxially with the input section of the dual-mass flywheel or, if necessary, compensating for an axial offset around its own axis of rotation, for example, the axis of rotation of the transmission input shaft, which is rotationally locked to the dual-mass flywheel. A pump impeller is directly integrated into the housing. When driven by rotation around the axis of rotation, the pump impeller fluidically transfers torque to a turbine impeller using a converter fluid. To increase torque at low speeds, a guide vane can be arranged between the pump impeller and the turbine impeller.

[0009] The torque converter lockup clutch is arranged over a large diameter and can therefore transmit high torques. Advantageously, the torque converter lockup clutch is integrated directly into the turbine wheel and the pump wheel, for example, by having an annular flange on the radial outside of the turbine wheel and a friction surface complementary to this annular flange being provided between the housing and the pump wheel. Friction linings can be provided on the annular flange and / or on the annular surface. The turbine wheel is axially displaceable relative to the pump wheel depending on the applied pressure or the flow of the torque converter fluid, so that the torque converter lockup clutch can be actuated by the influence of the flowing or pressurized torque converter fluid.

[0010] To achieve an axially narrow torque transmission device, the spring device at least partially overlaps the turbine wheel. This allows for effective use of the axial clearances defined by the contour of the turbine wheel. Advantageously, particularly to achieve a large diameter, both the torque converter lockup clutch and the spring device are arranged at the same radial height by arranging them on the outer circumference of the turbine wheel and pump wheel.

[0011] The torque transmission device can contain a detachable connection in order to be able to divide it into a subassembly mounted on the crankshaft and a subassembly mounted on the transmission, for example on the transmission input shaft, before assembly on the assembly line of a motor vehicle containing a drive train, and to later reconnect them. The detachable connection can be released again during maintenance or repair of the motor vehicle in order to be able to reversibly separate the internal combustion engine and transmission. The detachable connection is provided in particular in the torque flow downstream of the spring device and upstream of the housing of the torque converter. In this case, the housing with the turbine wheel essentially forms the secondary flywheel of the dual-mass flywheel.As a result, the torque transmission device is divided into an assembly located on the crankshaft and an assembly assigned to the transmission within the dual-mass flywheel. The detachable connection can be provided at the radial level of the torque converter lock-up clutch or radially within a maximum-extending installation space of the turbine wheel. In this case, the housing can replicate the contour of the turbine wheel.

[0012] Connecting elements for forming the detachable connection can be provided on the housing and on a flange part for loading the spring device on the output side. For example, the flange part can be connected, for example riveted, as a connecting element to connecting means arranged on the housing around the circumference, designed as connecting blocks, fastened to the housing and welded thereto. The detachable connection can be formed axially by a tool such as a screwdriver screwing the flange part to the housing through corresponding openings in the input part, thus establishing the detachable connection between the input part with the spring device as an assembly fastened to the crankshaft and the torque converter as an assembly mounted on the transmission input shaft of the transmission.In alternative embodiments, the detachable connection can be oriented radially or in the circumferential direction and can thus be formed or released by means of tools applied radially outward or in the circumferential direction.

[0013] At least one centrifugal pendulum is arranged between the input part and the output part of the torque transmission device. For example, the at least one centrifugal pendulum can be provided between the spring device and the housing.

[0014] Advantageously, at least one centrifugal pendulum absorber can be arranged at the same radial height as the torque converter lock-up clutch and the spring device. For example, at least one centrifugal pendulum absorber can be arranged axially between the spring device and the torque converter lock-up clutch. For example, at least one centrifugal pendulum absorber can be arranged outside the housing. A centrifugal pendulum absorber arranged outside the housing can be connected to the flange part for applying pressure to the spring device on the output side. For example, a pendulum mass carrier of a centrifugal pendulum absorber can be formed integrally from the flange part or connected to it. For example, the flange part and the pendulum mass carrier can be connected together with connecting elements of the housing to form the detachable connection between the two assemblies. Alternatively, the pendulum mass carrier can be connected to the housing, for example, welded.

[0015] At least one centrifugal pendulum can be arranged within the housing. For example, a pendulum mass carrier of a centrifugal pendulum can be connected to the housing. Alternatively or additionally, a pendulum mass carrier of a centrifugal pendulum can be connected to the turbine wheel, for example, welded or suspended and / or soldered into it.

[0016] The invention is based on the Fig. 1 to 3 are explained in more detail. They show: Fig. 1 shows a schematic representation of the upper part of a torque transmission device arranged around a rotational axis, Fig. 2 the upper part of one of the torque transmission devices of the Fig. 1 similar torque transmission device with a centrifugal pendulum arranged outside the housing of a torque converter in a schematic representation and Fig. 3 the upper part of one of the torque transmission devices of the Fig. 2 similar torque transmission device with a centrifugal pendulum arranged within a housing of a torque converter in a schematic representation.

[0017] The Fig. 1 shows a schematic representation of the upper part of the torque transmission device 1 arranged about the rotational axis d. The torque transmission device 1 is preferably arranged in a drive train of a motor vehicle between an internal combustion engine subject to torsional vibrations and having a crankshaft and a transmission with a transmission input shaft.

[0018] The torque transmission device 1 provides the functions of torsional vibration decoupling of a speed-dependent internal combustion engine and a starting element. The dual-mass flywheel 2 and the hydrodynamic torque converter 3 are provided for this purpose.

[0019] The torque converter 3 contains the housing 4 with the pump wheel 5, the turbine wheel 6 and the stator 7 which is connected to a transmission housing via a freewheel (not shown). In order to bridge the lossy fluidic transmission of torque via the pump wheel 5 to the turbine wheel 6, the turbine wheel 6 has the radially expanded annular flange 8 on the radial outside and the pump wheel 5 has the annular surface 9 at the transition to the housing 4, which, when the turbine wheel 6 is axially displaced relative to the pump wheel 5, due to a control of the converter fluid contained in the housing 4, switchably enter into frictional engagement and thus form the converter lock-up clutch 10. The torque converter 3 is rotatably mounted on a transmission input shaft of a transmission.

[0020] The dual-mass flywheel 2 has the input part 11, which is rotatable about the rotational axis d and is connected to the crankshaft of an internal combustion engine and forms the primary flywheel 12 of the dual-mass flywheel 2. The output part 26 of the torque transmission device 1, which contains or forms the secondary flywheel 13, is formed by the housing 4 and the pump wheel 5 of the torque converter 3, which is integrated into the housing. Between the input part 11 and the housing 4, the spring device 14 is provided, acting in the circumferential direction, with the spring elements 15, such as arc springs, distributed around the circumference. The spring elements 15 are accommodated in the annular chamber 16 formed by the input part 11 and are subjected to pressure on the input side by means of stamped portions of the input part 11. The pressure on the output side is applied by means of the flange part 17, whose radially expanded arms 18 engage between the spring elements 15 from the radial inside.

[0021] The detachable connection 19 is provided between the spring device 14 and the housing 4. The detachable connection 19 is formed by means of the connecting elements 20, 21 distributed over the circumference, which are connected from the axial direction by means of the screws 22 under the action of a tool inserted through a clutch bell or the like. For this purpose, corresponding openings (not shown) are provided in the input part 11. The connecting elements 20 are arranged radially inward on the flange part 17 and connected to the connecting elements 21 by means of the screws 22. The connecting elements 21 are provided as connecting blocks with an internal thread for the screws 22 and are connected, such as welded, radially within the axially maximum circumference of the turbine wheel 6 to the housing 4, which is adapted to the contour of the turbine wheel 6.The flange part 17 is guided around the contour of the housing 4, as if slightly offset, to achieve an axial overlap of the spring elements 15 with the turbine wheel 6 and thus reduce the axial installation space of the torque transmission device. In the illustrated embodiment, the spring elements 15 are essentially completely immersed in the axial installation space of the turbine wheel 6 and are arranged at the radial height of the torque converter lock-up clutch 10.

[0022] The Fig. 2 shows, in modification to the torque transmission device 1 of the Fig. 1 shows the torque transmission device 1a with the centrifugal pendulum 23a in the same schematic representation. The centrifugal pendulum 23a contains the pendulum mass carrier 24a and the pendulum masses 25a mounted thereon, pivotable along pendulum tracks and distributed over the circumference. The centrifugal pendulum 23a is arranged outside the housing 4a of the torque converter 3a. The pendulum masses 25a are mounted axially between the spring elements 15a of the spring device 14a of the dual-mass flywheel 2a and the torque converter lock-up clutch 10a, and radially at the same height. In this sense, the centrifugal pendulum 23a is at the radial height of the spring device 14a and the torque converter lock-up clutch 10a, since the pendulum mass carrier 24a contributes essentially nothing to the speed-adaptive damping effect of the centrifugal pendulum 23a.The spring elements 15a overlap the axial installation space of the turbine wheel 6a to reduce the axial installation space of the torque transmission device 1a. The pendulum mass carrier 24a is received radially inwardly together with the flange part 17a on the connecting elements 21a of the housing 4a and forms the detachable connection 19a therewith.

[0023] The Fig. 3 shows, in modification to the torque transmission device 1a of the Fig.2 shows the torque transmission device 1b with the centrifugal pendulum 23b arranged within the housing 4b in the same illustration. The housing 4b is axially expanded in the radial region of the torque converter lock-up clutch 10b and accommodates the pendulum masses 25b of the centrifugal pendulum 23b. The pendulum mass carrier 24b is axially folded radially within the pendulum masses 25b and connected to the housing 4b, such as by welding. In further embodiments, a flat, ring-shaped pendulum mass carrier can be connected to the radially outer inner circumference of the housing 4b, such as by welding. The pendulum masses 25b are arranged axially between the spring elements 15b of the spring device 14b and the torque converter lock-up clutch 10b and radially at the same height. The spring elements 15b overlap the axial installation space of the turbine wheel 6b to reduce the axial installation space of the torque transmission device 1b. List of reference symbols 1 torque transmission device 1a Torque transmission device 1b Torque transmission device 2 dual-mass flywheel 2a Dual-mass flywheel 3 torque converters 3a torque converter 4 housings 4a housing 4b housing 5 Pump wheel 6 Turbine wheel 6a Turbine wheel 6b Turbine wheel 7 Idler 8 Ring flange 9 Ring area 10 torque converter lock-up clutch 10a torque converter lock-up clutch 10b torque converter lock-up clutch 11 Entrance part 12 Primary flywheel 13 Secondary flywheel 14 Spring device 14a Spring device 14b Spring device 15 Spring element 15a Spring element 15b Spring element 16 Annular chamber 17 Flange part 17a Flange part 18 arms 19 detachable connection 19a detachable connection 20 connecting element 21 Connecting element 21a Connecting element 22 Screw 23a Centrifugal pendulum 23b Centrifugal pendulum 24a Pendulum mass carrier 24b Pendulum mass carrier 25a Pendulum mass 25b Pendulum mass 26 Output part d axis of rotation

Claims

[1] Torque transmission device (1, 1a, 1b) with a dual-mass flywheel (2, 2a) with an input part (11) which is arranged such that it can rotate about an axis of rotation (d), which is connected to the crankshaft of an internal combustion engine and forms the primary flywheel (12) of the dual-mass flywheel (2), an output part (26) which is arranged such that it can rotate about the axis of rotation (d) against the action of a spring device (14, 14a, 14b), to which a secondary flywheel (13) is assigned, wherein the secondary flywheel (13) is formed from a housing (4, 4a, 4b) of the torque converter (3, 3a) and the pump wheel (5) integrated into the housing (4, 4a, 4b), and a hydrodynamic torque converter (3, 3a) with a turbine wheel (6, 6a, 6b), a pump wheel (5) and a converter lock-up clutch (10, 10a, 10b), wherein the converter lock-up clutch (10, 10a, 10b) is arranged on the outer circumference of the turbine wheel (6, 6a,6b) and the pump wheel (5) and the spring device (14, 14a) at least overlaps the axial installation space of the turbine wheel (6, 6a, 6b), wherein at least one centrifugal pendulum (23a, 23b) is arranged between the input part (11) and the output part (26), wherein the centrifugal pendulum (23a, 23b) is arranged axially between the spring device (14a, 14b) and the converter lock-up clutch (10a, 10b). [2] Torque transmission device (1, 1a, 1b) according to claim 1, characterized by that the spring device (14, 14a) and the converter lock-up clutch (10, 10a, 10b) are arranged at the same radial height. [3] Torque transmission device (1, 1a, 1b) according to one of claims 1 to 2, characterized by that a detachable connection (19, 19a) is provided between the spring device (14, 14a) and the housing (4, 4a, 4b). [4] Torque transmission device (1a, 1b) according to claims 1 to 3, characterized bythat at least one centrifugal pendulum (23a, 23b) is arranged at the same radial height as the converter lock-up clutch (10a, 10b) and the spring device (14a, 14b). [5] Torque transmission device (1a) according to one of claims 1 to 4, characterized by that at least one centrifugal pendulum (23a) is arranged outside the housing (4a). [6] Torque transmission device (1b) according to one of claims 1 to 5, characterized by that at least one centrifugal pendulum (23b) is arranged within the housing (4b).

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