HYDRODYNAMIC TORQUE CONVERTER HAVING CONVERTER LOCK-UP CLUTCH

Abstract

A hydrodynamic torque converter is provided with a converter housing and a converter torus with a pump impeller, a turbine wheel which is driven hydrodynamically by the pump impeller by a converter fluid. In order to bridge the hydrodynamic drive, a converter lock-up clutch which is connected between the pump impeller and the turbine wheel by pressure loading of the converter fluid is arranged radially between an outer circumference of the converter housing and the converter torus. In order to provide the converter lock-up clutch with an increased transmission capacity, the turbine wheel is assigned at least one friction disc which can be prestressed axially between a pressure-loaded annular piston, which is hooked in an axially movable manner into the converter housing, and a mating friction surface of a converter housing section radially outside the converter torus.

Claims

1. A hydrodynamic torque converter comprising a converter housing and a converter torus having a pump impeller, a turbine wheel driven hydrodynamically by the pump impeller by a converter fluid, wherein, in order to bridge a hydrodynamic drive, a converter lock-up clutch which is connected between the pump impeller and the turbine wheel by pressure loading of the converter fluid is arranged radially between an outer circumference of the converter housing and the converter torus, wherein the turbine wheel is assigned at least one friction disc which can be prestressed axially between a pressure-loaded annular piston, which is provided with a friction lining and which is hooked in an axially movable manner into the converter housing, and a mating friction surface of a converter housing section radially outside the converter torus.

2. The hydrodynamic torque converter according to claim 1, wherein a single friction disc is integrally connected to the turbine wheel and carries a friction lining on a side facing the converter housing section.

3. The hydrodynamic torque converter according to claim 1, wherein an inner multiple disc carrier is attached to the turbine wheel, into which inner multiple disc carrier at least one friction disc is hooked in a non-rotatable manner.

4. The hydrodynamic torque converter according to claim 3, wherein a plurality of friction discs are arranged in an axially alternating manner, with at least one friction disc hooked in a non-rotatable manner into an outer multiple disc carrier connected to the converter housing.

5. The hydrodynamic torque converter according to claim 3, wherein an input part of a torsional vibration damper is attached to the turbine wheel.

6. The hydrodynamic torque converter according to claim 5, wherein the input part forms the inner multiple disc carrier.

7. The hydrodynamic torque converter according to claim 4, wherein the outer multiple disc carrier is formed from a ring part connected to the converter housing.

8. The hydrodynamic torque converter according to claim 4, wherein the outer multiple disc carrier is formed in the converter housing.

9. The hydrodynamic torque converter according to claim 5, wherein a centrifugal pendulum is received on the torsional vibration damper.

10. The hydrodynamic torque converter according to claim 9, wherein a pendulum mass carrier of the centrifugal pendulum is integrally connected to a side part loading helical compression springs of the torsional vibration damper.

11. A hydrodynamic torque converter, comprising: a converter housing formed by first and second housing shells that axially overlap and are connected to one another; a converter torus having a pump impeller and a turbine wheel driven hydrodynamically by the pump impeller by a converter fluid, wherein the first housing shell forms an impeller shell of the pump impeller; and a converter lock-up clutch connected between the pump impeller and the turbine wheel by pressure loading of the converter fluid, the converter lock-up clutch being further arranged radially between an outer circumference of the converter housing and the converter torus, wherein the turbine wheel includes a turbine wheel friction disc configured to be prestressed axially between a pressure-loaded annular piston and a mating friction surface of the first housing shell of the converter housing located radially outside the converter torus.

12. The hydrodynamic torque converter according to claim 11, wherein the pressure-loaded annular piston is hooked in an axially movable manner into the converter housing and sealed to an inner surface of the first housing shell by a sealing ring.

13. The hydrodynamic torque converter according to claim 11, wherein, in response to the converter housing being filled with the converter fluid, the pressure-loaded annular piston is configured to be displaced axially and prestress the turbine wheel friction disc against the mating friction surface to form a frictional engagement therewith.

14. The hydrodynamic torque converter according to claim 11, wherein the turbine wheel friction disc is integrally connected with the turbine wheel.

15. The hydrodynamic torque converter according to claim 11, wherein the converter lock-up clutch further comprises: a plurality of friction discs disposed axially between the pressure-loaded annular piston and the turbine wheel friction disc; and an inner multiple disc carrier attached to the turbine wheel, wherein at least one of the plurality of friction discs is hooked into the inner multiple disc carrier in a non-rotatable manner.

16. The hydrodynamic torque converter according to claim 15, wherein the converter lock-up clutch further includes an outer multiple disc carrier connected to the converter housing, wherein the plurality of friction discs are arranged in an axially alternating manner with at least one of the plurality of friction discs hooked in a non-rotatable manner into the outer multiple disc carrier.

17. The hydrodynamic torque converter according to claim 15, further comprising a torsional vibration damper including an input part attached to the turbine wheel, wherein the input part forms the inner multiple disc carrier.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The disclosure is explained in more detail with reference to the exemplary embodiments shown in FIGS. 1 to 5. These show:

[0015] FIG. 1 shows a sectional view of the upper part of a hydrodynamic torque converter, which is arranged around an axis of rotation,

[0016] FIG. 2 shows a sectional view of the upper part of a torque converter with a disc stack, which is arranged around an axis of rotation and has been modified compared to the torque converter in FIG. 1,

[0017] FIG. 3 shows a sectional view of the upper part of a torque converter with a disc stack, which is arranged around an axis of rotation and has been modified compared to the torque converter of FIG. 2,

[0018] FIG. 4 shows a sectional view of the upper part of a torque converter with a disc stack, which is arranged around an axis of rotation and has been modified compared to the torque converter of FIGS. 1 to 3 and

[0019] FIG. 5 shows a sectional view of the upper part of a torque converter with a disc stack, which is arranged around an axis of rotation and has been modified compared to the torque converter of FIG. 4.

DETAILED DESCRIPTION

[0020] FIG. 1 shows a sectional view of the upper part of the hydrodynamic torque converter 1, which is arranged so that it can be rotated around the axis of rotation d. The converter housing 2 is formed by the two housing shells 3, 4, which axially overlap radially outside and are tightly connected to one another. The housing shell 3 contains the pump impeller 5 with drive discs distributed around the circumference. Axially opposite is the turbine wheel 6 with discs designed to complement the drive discs of the pump impeller 5 and attached to the turbine shell 7. The guide wheel 8 is arranged between the pump impeller 5 and the turbine wheel 6. The pump impeller 5, the turbine wheel 6 and the guide wheel 8 form the converter torus 9.

[0021] Radially outside the converter torus 9 and in its axial installation space is the converter lock-up clutch 10, which contains the annular piston 11, the friction disc 12 and the mating friction surface 13 on the converter housing section 14 as functional components.

[0022] The annular piston 11 is received by means of the profiling 15 of the housing shell 4 in a non-rotatable manner and sealed to the converter housing 2 and with respect to it by means of the sealing ring 16. By increasing the pressure in the chamber 17 of the converter housing 2 filled with converter fluid, the annular piston 11 is displaced axially and prestresses the friction disc 12 against the mating friction surface 13, forming a frictional engagement.

[0023] The friction disc 12 is formed integrally from the turbine shell 7 by radial extension of the latter. The friction disc 12 contains the friction lining 18 facing the mating friction surface 13. The frictional engagement between the annular piston 11 and the friction disc 12 is formed by means of the friction lining 19 arranged on the annular piston 11 and a steel surface of the friction disc 12. To improve actuation of the torque converter lock-up clutch 10, the friction lining 19 has no grooves and thus forms a sealed friction surface to the friction disc 12, while the friction lining 18 forms grooves 18a from radially inward to radially outward so that excess converter fluid is displaced radially inward when the torque converter lock-up clutch 10 is closed.

[0024] The hydrodynamic torque converter 1 contains, within the chamber 17, the torsional vibration damper 20, the input part 21 of which is connected to the turbine wheel 6 and the output part 22 of which forms the output hub 23 with the internal toothing 24, which is rotationally connected, for example, by means of a gearbox input shaft of a gearbox.

[0025] The torsional vibration damper 20 is designed in two stages and for this purpose has helical compression springs 25 distributed radially on the outside over the circumference and short helical compression springs 26 distributed radially on the inside over the circumference. The helical compression springs 25 are supported in the retaining shell 27 against the action of centrifugal forces and are loaded by the latter on the output side. The input side loading takes place by means of the flange part 28 designed as an input part 21, which is welded to the turbine shell 7. The helical compression springs 25 are arranged radially outside the converter torus 9 in the chamber 17 to save installation space.

[0026] The helical compression springs 26 are arranged radially within the maximum axial extent of the turbine wheel 6 to save installation space and are received in window-shaped recesses in the side parts 29, 30 and the output flange 31 arranged between them, and are loaded on the input and output sides. The side parts 29, 30 are connected to one another in an axially spaced manner by means of the spacer bolts 32 and support the helical compression springs 26 by means of axially flared window sashes 33. The damper stages are connected to the helical compression springs 25, 26 by means of the retaining shell 27, which forms the side part 30 facing the turbine shell 7. The output flange 31 is integrally connected to the output hub 23.

[0027] The turbine wheel 6 is centered on a shaft not shown, such as the gearbox input shaft of a gearbox, by means of the turbine flange 34, which is connected to the turbine shell 7 by means of the rivet 35. The torsional vibration damper 20 is effective between the converter housing 2 and the output hub 23 when the converter lock-up clutch 10 is closed. When the converter lock-up clutch 10 is open, the torsional vibration damper 20 acts as a so-called turbine damper by forwarding the torque transmitted from the pump impeller 5 to the turbine wheel 6 to the output hub 23 via the torsional vibration damper 20.

[0028] FIG. 2 shows a sectional view of the upper part of the hydrodynamic torque converter 101, which is similar to the hydrodynamic torque converter 1 and is arranged so that it can be rotated around the axis of rotation d. In contrast to the hydrodynamic torque converter 1, the hydrodynamic torque converter 101 has the converter lock-up clutch 110 with the friction disc 136 in addition to the friction disc 112 formed from the turbine shell 107 of the turbine wheel 106. The friction disc 136 is hooked in a non-rotatable manner into the input part 121 of the torsional vibration damper 120, which acts as an inner multiple disc carrier 137, by means of an inner profiling. To form a disc stack 138, the friction disc 140 is hooked in a non-rotatable manner into the outer multiple disc carrier 139 of the housing shell 103 of the converter housing 102.

[0029] Here, the annular piston 111, the friction disc 136, the friction disc 140, the friction disc 112, and the mating friction surface 113 of the converter housing section 114 form the layering of the disc stack 138. The annular piston 111 carries the friction lining 119, the friction discs 112, 136, 140 each carry friction linings 118, 141, 142 on their side facing away from the annular piston 111, so that a friction lining/steel friction pairing is formed in each case.

[0030] FIG. 3 shows a sectional view of the upper part of the hydrodynamic torque converter 201, which is arranged around the axis of rotation d and is similar to the hydrodynamic torque converter 101 of FIG. 2. Unlike the hydrodynamic torque converter 101, the hydrodynamic torque converter 201 has the converter lock-up clutch 210 with the disc stack 238, the inner multiple disc carrier 237 of which is designed to be separate from the flange part 228 of the input part 221 of the torsional vibration damper 220. The inner multiple disc carrier 237 and the flange part 228 are each independently welded to the turbine shell 207 of the turbine wheel 206. The inner multiple disc carrier 237 also includes the radial support weld 243 to prevent the inner multiple disc carrier 237 from deflecting radially inward.

[0031] FIG. 4 shows the upper part of the hydrodynamic torque converter 301 arranged around the axis of rotation d, which is provided with the centrifugal pendulum 344 in modification with respect to the hydrodynamic torque converters 1, 101, 201 of FIGS. 1 to 3.

[0032] The centrifugal pendulum 344 is connected to the output side part of the torsional vibration damper 320. In the exemplary embodiment shown, the pendulum mass carrier 345 is integrally formed with the side part 329. The pendulum masses 346, which are received in a pendulum-capable manner on the pendulum mass carrier 345 on both sides by means of pendulum bearings not shown in the centrifugal force field of the torque converter 301 rotating around the axis of rotation d, are received at the radial height of the helical compression springs 325. To save axial installation space, the retaining shell 327 is designed as an input part 321 on the input side and welded to the turbine shell 307 of the turbine wheel 306. The pendulum mass carrier 345 and the flange part 328 loading the output side of the helical compression springs 325 form the side parts 329, 330 spaced apart axially by means of the spacer bolts 332 for loading the input side of the helical compression springs 326 arranged radially on the inside. The output flange 331 arranged between the side parts 329, 330 handles the output-side loading of these.

[0033] FIG. 5 shows a sectional view of the upper part of the hydrodynamic torque converter 401, which is arranged so that it can be rotated around the axis of rotation d. As an alternative to the outer multiple disc carriers shown in FIGS. 2 to 4, which are formed from a ring part inserted into the converter housing and connected in a non-rotatable manner, the outer multiple disc carrier 439 is formed integrally from the housing shell 403 of the converter housing 402. For this purpose, indentations 448 are provided in the axial projection 447 of the housing shell 403, distributed over the circumference in a radially inward direction and forming the inner profile of the outer multiple disc carrier 439. It is to be understood that the outer multiple disc carriers of the torque converters 101, 201, 301 of FIGS. 2 to 4 can also include such indentations 448.

LIST OF REFERENCE SIGNS

[0034] 1 Hydrodynamic torque converter [0035] 2 Converter housing [0036] 3 Housing shell [0037] 4 Housing shell [0038] 5 Pump impeller [0039] 6 Turbine wheel [0040] 7 Turbine shell [0041] 8 Guide wheel [0042] 9 Converter torus [0043] 10 Converter lock-up clutch [0044] 11 Annular piston [0045] 12 Friction disc [0046] 13 Mating friction surface [0047] 14 Converter housing section [0048] 15 Profiling [0049] 16 Sealing ring [0050] 17 Chamber [0051] 18 Friction lining [0052] 18a Groove [0053] 19 Friction lining [0054] 20 Torsional vibration damper [0055] 21 Input part [0056] 22 Output part [0057] 23 Output hub [0058] 24 Internal toothing [0059] 25 Helical compression spring [0060] 26 Helical compression spring [0061] 27 Retaining shell [0062] 28 Flange part [0063] 29 Side part [0064] 30 Side part [0065] 31 Output flange [0066] 32 Spacer bolt [0067] 33 Window sash [0068] 34 Turbine flange [0069] 35 Rivet [0070] 101 Hydrodynamic torque converter [0071] 102 Converter housing [0072] 103 Housing shell [0073] 106 Turbine wheel [0074] 107 Turbine shell [0075] 110 Converter lock-up clutch [0076] 111 Annular piston [0077] 112 Friction disc [0078] 113 Mating friction surface [0079] 114 Converter housing section [0080] 118 Friction lining [0081] 119 Friction lining [0082] 120 Torsional vibration damper [0083] 121 Input part [0084] 136 Friction disc [0085] 137 Inner multiple disc carrier [0086] 138 Disc stack [0087] 139 Outer multiple disc carrier [0088] 140 Friction disc [0089] 141 Friction lining [0090] 142 Friction lining [0091] 201 Hydrodynamic torque converter [0092] 206 Turbine wheel [0093] 207 Turbine shell [0094] 210 Converter lock-up clutch [0095] 220 Torsional vibration damper [0096] 221 Input part [0097] 228 Flange part [0098] 237 Inner multiple disc carrier [0099] 238 Disc stack [0100] 243 Support weld [0101] 301 Hydrodynamic torque converter [0102] 306 Turbine wheel [0103] 307 Turbine shell [0104] 320 Torsional vibration damper [0105] 321 Input part [0106] 325 Helical compression spring [0107] 326 Helical compression spring [0108] 327 Retaining shell [0109] 328 Flange part [0110] 329 Side part [0111] 330 Side part [0112] 331 Output flange [0113] 332 Spacer bolt [0114] 344 Centrifugal pendulum [0115] 345 Pendulum mass carrier [0116] 346 Pendulum mass [0117] 401 Hydrodynamic torque converter [0118] 402 Converter housing [0119] 403 Housing shell [0120] 439 Outer multiple disc carrier [0121] 447 Projection [0122] 448 Indentation [0123] d Axis of rotation