CN112555381A

CN112555381A - Hydraulic torque converter

Info

Publication number: CN112555381A
Application number: CN201910916282.2A
Authority: CN
Inventors: 孟腾; 李茂辉; 李璐; 王盛璋
Original assignee: Faroeco Torque Converter Nanjing Co ltd
Current assignee: Faroeco Torque Converter Nanjing Co ltd
Priority date: 2019-09-26
Filing date: 2019-09-26
Publication date: 2021-03-26
Also published as: JP2022549699A; JP7399272B2; WO2021057905A1; KR102607836B1; KR20220059546A; DE112020004569T5; MX2022003683A

Abstract

The present disclosure relates to a torque converter, comprising: a housing disposed about an axis of rotation for receiving an input torque; an impeller disposed about a rotational axis and including an impeller housing, an impeller core ring, and a plurality of impeller blades; a turbine disposed axially opposite the pump impeller about the axis of rotation, the turbine including a turbine housing and a plurality of turbine blades; an output hub disposed about the axis of rotation and fixedly connected to the turbine housing for outputting torque; wherein, this torque converter still includes: an inner friction disk disposed about the rotational axis and interposed axially between the pump impeller and the turbine wheel, the inner friction disk having a plurality of resilient members disposed thereon, the plurality of resilient members being retained between the inner friction disk and the pump impeller core ring; and wherein the turbine is axially displaceable between a locking position in which the turbine housing engages and forms a locking connection with the inner friction disc, and a disengaged position in which the turbine housing is disengaged from the inner friction disc.

Description

Hydraulic torque converter

Technical Field

The present disclosure relates to a torque converter, and more particularly to a torque converter having an inner friction disk.

Background

Typically, a torque converter is provided between the engine and the transmission of an automatically shifting motor vehicle. The torque converter serves to transmit driving power of an engine to a transmission by using fluid (usually oil), and functions to transmit torque and convert torque.

A torque converter typically includes a housing, an impeller, a turbine, a lockup clutch, a damper, and an output hub. The pump impeller and the turbine wheel are axially opposed. The impeller includes an impeller housing that rotates with the casing, and a plurality of impeller blades fixed to the impeller housing. The turbine includes a turbine housing fixedly connected to the output hub and a plurality of turbine blades fixed to a side of the turbine housing facing the impeller. The turbine housing and the impeller housing together enclose a circle of revolution, as is known in the art.

In some prior art, a lockup clutch is formed between the pump impeller and the turbine runner. For example, in chinese patent application CN106574701A, the turbine housing acts as a piston disc for the lock-up clutch and includes a first friction pair that is axially movable into and out of engagement with an impeller housing that includes a second friction pair. In US patent application US2015152951a1, a first piston disc and a second piston disc are arranged between the pump wheel housing and the turbine wheel housing, the first piston disc being arranged floating between the turbine wheel and the second piston disc, the second piston disc being connected to the turbine wheel without limiting its axial displacement.

In the above-described prior art, the dampers are each formed outside a circle defined by the turbine housing and the pump housing together. The damper generally includes a drive plate connected to the lockup clutch and a driven plate fixedly connected to the output hub, and a circumferentially acting elastic member. A circumferentially acting resilient member is interposed between the drive disc and the driven disc. It has been found that the presence of multiple members of the damper occupies a large space inside the torque converter, particularly in the axial direction.

Disclosure of Invention

The purpose of the disclosure is to improve the utilization rate of the internal space of the hydraulic torque converter and simplify the overall dimension of the hydraulic torque converter through a smart dual-purpose design of parts.

The present disclosure provides a torque converter, comprising: a housing disposed about an axis of rotation for receiving an input torque; an impeller disposed about the axis of rotation and including an impeller housing, an impeller core ring, and a plurality of impeller blades; a turbine disposed axially opposite the pump impeller about the axis of rotation, the turbine including a turbine housing and a plurality of turbine blades; an output hub disposed about the axis of rotation and fixedly connected to the turbine housing for outputting a torque; wherein, this torque converter still includes: an inner friction disk disposed about the rotational axis and axially between the pump impeller and the turbine wheel, the inner friction disk having a plurality of resilient members disposed thereon, the plurality of resilient members being retained between the inner friction disk and the pump impeller core ring to transfer torque from the pump impeller to the inner friction disk via the plurality of resilient members; and wherein said turbine is axially displaceable between a locking position in which said turbine housing engages and forms a locking connection with said inner friction disc and a disengaged position in which said turbine housing is disengaged from said inner friction disc.

In the torque converter according to the present disclosure, the inner friction plates serve as components of both the lock-up clutch and the damper, and function as the elastic member holding plate of the damper and the friction plates of the lock-up clutch. Two parts, which are usually separated from each other, are merged into one part, and a damper, which is usually located outside a first chamber formed by the pump wheel housing and the turbine housing, is provided inside the first chamber. Thus, the torque converter may have a smaller volume, and the space saved provides a rich design choice, e.g., for adding additional components, etc. In addition, the torque converter may have a lighter weight, which allows to reduce the energy consumption of the motor vehicle in which it is installed, complying with the current environmental requirements of energy saving and emission reduction.

In some embodiments, the inner friction disc is annular in shape, the inner friction disc including an inner peripheral portion located radially inward thereof, the inner peripheral portion including a plurality of elastic member retaining windows extending in a circumferential direction, adjacent two of the elastic member retaining windows being separated from each other in the circumferential direction by a radial partition, the plurality of elastic member members being retained between the plurality of elastic member retaining windows and the pump wheel core ring in the axial direction.

Thus, the component parts of the damper (the pump wheel core ring, the elastic member, and the elastic member holding window) are located at the intermediate positions in the radial direction of the first chamber without occupying the fluid transmission path of the hydraulic drive between the pump wheel and the turbine wheel. Thus, the torque converter according to the present disclosure makes full use of the inner space of the first chamber at the radial middle position to arrange the damper, greatly reduces the size of the torque converter in the radial direction, and has a compact structure so as to adapt to the trend of reducing the size of the components in the current automobile industry.

In some embodiments, the pump wheel core ring includes a plurality of drive tabs extending toward the inner friction disk. Each resilient member is circumferentially compressed between the drive tabs of the pump wheel core ring and the radial partitions of the inner friction disk.

In some embodiments, the inner friction disc comprises an outer peripheral portion radially outward thereof, the outer peripheral portion comprising a first surface facing the pump impeller and a second surface facing the turbine wheel, the second surface having friction discs disposed thereon for forming a locking connection with the turbine housing.

In some embodiments, a first limit bushing is provided at a first surface of an outer peripheral portion of the inner friction disc, the first limit bushing being annular in shape about the rotational axis for axially supporting the inner friction disc when the turbine wheel is in a locked position.

In some embodiments, a seal ring is disposed at a first surface of an outer peripheral portion of the inner friction disc.

In some embodiments, a plurality of centering bosses are provided in the inner friction disc for centering the seal ring and/or the first check bushing relative to the rotational axis. The sealing ring is annular in shape around the axis of rotation for forming a fluid seal between the pump wheel housing 31 and the inner friction disc 5 when the turbine wheel is in the locked position, thereby ensuring a pressure difference between the first and second chambers. Thus, the inner friction disc and the turbine housing form a tight and secure friction-locked connection, thereby ensuring efficiency of torque transmission in the rigid transmission mode.

In some embodiments, the outer and inner peripheral portions of the inner friction disk are connected by a plurality of radial webs, adjacent radial webs forming circumferentially extending fluid communication windows therebetween. The fluid communication window allows passage of a hydrodynamic transmission fluid circulating within the first chamber while reducing the weight of the inner friction discs and the overall torque converter.

In some embodiments, each radial web is radially aligned with a respective radial partition of the inner peripheral portion, thereby enhancing the mechanical strength of the inner friction disc 5 as a torque transmitting member.

In some embodiments, a second restraining bushing is disposed between the output hub and the outer casing, the second restraining bushing being annular in shape about the axis of rotation for axially supporting the output hub when the turbine is in the disengaged position.

In some embodiments, a plurality of radially extending fluid passages are provided in the second position-defining bushing to allow fluid to flow into or out of the space between the turbine casing and the outer shell.

The present disclosure also provides a motor vehicle comprising a torque converter as described above.

Drawings

The accompanying drawings are incorporated in and constitute a part of this specification. Together with the general description given above, and the detailed description of exemplary embodiments and methods given below, the drawings serve to explain the principles of the disclosure. The objects and advantages of the present disclosure will become apparent upon a study of the following specification in light of the accompanying drawings, in which like elements are given the same or similar reference numerals, and in which:

FIG. 1 is a schematic illustration of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 2 is an exploded view of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 3 illustrates an inner friction disk of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 4 illustrates a configuration of an outer peripheral portion and an inner peripheral portion of an inner friction disk of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 5 illustrates a pump wheel core ring of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 6 illustrates a second limit bushing of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 7 illustrates in detail a portion of an inner friction disk of a torque converter according to an exemplary embodiment of the present disclosure;

FIG. 8 illustrates a fluid flow path of a torque converter in a locked condition according to an exemplary embodiment of the present disclosure; and

FIG. 9 illustrates a torque transfer path of a torque converter in a locked state according to an exemplary embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary embodiments and methods of the present disclosure as illustrated in the accompanying drawings, in which like reference numerals designate identical or corresponding parts. It should be noted, however, that the disclosure in its broader aspects is not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described in connection with the exemplary embodiments and methods.

This description of the exemplary embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description, relative terms such as "upper," "lower," "left," "right," and derivatives thereof (e.g., "downward," "upward," etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description and are not intended to require a particular orientation. Unless expressly stated otherwise, the terms "connected," coupled, "and the like refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships. The term "operatively connected" is a connection that allows the associated structure to have the connection during operation or actual use. In addition, the words "a" and "an" as used in the claims mean "at least one" and the words "two" as used in the claims mean "at least two".

A first exemplary embodiment of a torque converter 1 is shown generally in fig. 1. The torque converter 1 receives input torque from an engine and transmits the torque to an input shaft (not shown) of a transmission, such as in a motor vehicle.

It should be understood that the axial and radial orientations are considered relative to the rotational axis X of the hydrodynamic torque converter 1. Relative terms such as "axially", "radially" and "circumferentially" relate to orientations parallel, perpendicular and circularly around the axis of rotation X, respectively.

The figures discussed here show only half of the hydrodynamic torque converter 1, i.e. a partial or partial cross section of the hydrodynamic torque converter 1 above the axis of rotation X. As is known in the art, the torque converter 1 is circumferentially symmetrical about the axis of rotation X.

The torque converter 1 includes a housing 2 as an input member, the housing 2 being disposed around a rotation axis X. The housing 2 receives torque from the engine as input torque to the torque converter 1. The housing 2 rotates at the same speed as the speed of the output shaft of the engine.

The torque converter 1 further includes an output hub 6 as an output member, which is disposed around the rotation axis X. The output hub 6 is coupled to and disposed coaxially with the input shaft of the transmission. For example, the output hub 6 may be provided with internal splines for non-rotatably coupling the output hub 6 to an input shaft of a transmission provided with complementary external splines. Alternatively, a weld or other connection may be used to secure the output hub 6 to the input shaft of the transmission.

The torque converter 1 shown in fig. 1 includes a pump impeller 3 disposed around a rotation axis X, a turbine runner 4 disposed around the rotation axis X and coaxially aligned with the pump impeller 3, and a stator disposed between the pump impeller 3 and the turbine runner 4.

The impeller 3 comprises a generally annular impeller housing 31, an impeller core ring 32 and a plurality of impeller vanes 34, said impeller vanes 34 being firmly attached to the impeller housing 31 and the impeller core ring 32, such as by brazing. The impeller 3 is fixed to the casing 2 and is therefore connected to the drive shaft (or flywheel) of the engine, so as to rotate at the same speed as the engine output shaft. In some embodiments, as shown in fig. 1, the pump wheel housing 31 is axially opposite the outer casing 2 and is fixed to the outer casing 2 by the weld 21.

The turbine 4 is arranged axially opposite the pump wheel 3 and can be hydraulically driven by it. The turbine 4 includes a turbine housing 41 and a plurality of turbine blades 43. The turbine 4 includes a turbine housing 41, a generally annular turbine 4 core ring, and a plurality of turbine blades 43, the turbine blades 43 being securely attached to the turbine housing 41 and the turbine 4 core ring, such as by brazing. The turbine housing 41 is fixedly connected to the output hub 6, for example by rivets. The turbine blades 43 are fixed to the side of the turbine housing 41 facing the pump impeller 3. The turbine 4 and the stator together form a circle of revolution. In the hydrodynamic transmission mode of the torque converter 1, the impeller 3 and the turbine runner 4 can transmit power through fluid without a rigid connection, as is known in the art.

The pump casing 31 and the turbine casing 41 define a first chamber 11 (or a torus chamber) therebetween. The turbine housing 41 and the casing 2 define a second chamber 12 therebetween. Referring to fig. 1, the first chamber 11 is located generally on the left side of the turbine housing 41 and the second chamber 12 is located generally on the right side of the turbine housing 41.

According to some embodiments of the present disclosure, the torque converter 1 further comprises a substantially annular inner friction disc 5, which is arranged around the rotation axis X and is axially interposed between the pump impeller 3 and the turbine runner 4.

The inner friction discs 5 form part of a lock-up clutch of the torque converter 1. The lock-up clutch is configured to mechanically transmit torque when in the locked position. The lockup clutch is normally locked after a starting process of the hydraulic transmission of the motor vehicle in order to avoid efficiency losses, for example caused by slip phenomena between the turbine 4 and the pump impeller 3. The lockup clutch further includes a turbine housing 41 forming a piston portion of the lockup clutch. The turbine 4, and therefore the turbine housing 41, is axially displaceable between a locked position and a disengaged position. In the locked position, the turbine housing 41 engages and forms a locked connection with the inner friction discs 5 and the torque converter 1 operates in a rigid transmission mode. In the disengaged position, the turbine housing 41 is disengaged from the inner friction discs 5 and the torque converter 1 operates in a hydrodynamic transmission mode.

The inner friction disc 5 also forms part of a damper of the torque converter 1. Referring to fig. 2 and 4, a plurality of elastic members 7 are provided on the inner friction disc 5, and the plurality of elastic members 7 are held between the inner friction disc 5 and the pump wheel core ring 32 to transmit torque from the pump wheel 3 to the inner friction disc 5 via the plurality of elastic members 7, while the plurality of elastic members 7 can absorb abrupt torque.

The inner friction discs 5 serve as components of both the lock-up clutch and the damper, as described above. In this way, two components, which are usually separated from each other, are merged into one component, and the damper, which is usually located outside the first chamber 11 formed by the pump casing 31 and the turbine casing 41, is disposed inside the first chamber 11. Thus, the torque converter may have a smaller volume, and the space saved provides a rich design choice, e.g., for adding additional components, etc. In addition, the torque converter can have a lighter weight, which makes it possible to reduce the energy consumption of the motor vehicle on which it is installed, complying with the current trend towards energy conservation and emission reduction.

Referring to fig. 2 to 4, the inner friction disc 5 includes an outer peripheral portion 52 on a radially outer side thereof. The peripheral portion 52 extends substantially radially and comprises a first surface 52a facing the impeller 3 and a second surface 52b facing the turbine 4 (fig. 4). As best shown in fig. 1 and 4, a friction plate 54 is provided at the second surface 52b for forming a locking connection with the turbine housing 41. Friction plate 54 is, for example, annular in shape and is securely attached at second surface 52b by suitable means known in the art, such as by adhesive bonding.

The turbine housing 41 includes a generally annular flat flange 42. The flange 42 is a radial extension of the turbine housing 41 and, as shown in fig. 1, is disposed radially outward of the turbine blades 43. The turbine flange 42 is integral with other portions of the turbine housing 41, for example, made of a single or unitary component, but may also be separate components that are joined together. The flange 42 of the turbine housing 41 axially overlaps the second surface 52b of the inner friction disc 5. As explained below, the turbine housing 41 and its flange 42 may be moved axially toward the second surface 52b or away from the second surface 52b of the inner friction disk 5 to enter a locked or disengaged position.

According to some embodiments of the present disclosure, fluid may flow into or out of the second chamber 12 on one side of the turbine housing 41 to drive axial movement of the turbine housing. The flow of fluid is controlled, for example, by a valve. When the valve is opened, fluid may flow into the second chamber 12 on one side of the turbine housing 41, and the fluid pressure in the second chamber 12 gradually increases until it is greater than the pressure in the first chamber 11 on the other side of the turbine housing 41, thereby driving the turbine housing 41 axially toward the second surface 52b of the inner friction disk 5. Thereby, the lock-up clutch is locked. Conversely, when the valve is closed, fluid may flow out of the second chamber 12 on one side of the turbine housing 41, such that the pressure in the second chamber 12 gradually decreases until less than the pressure in the first chamber 11 on the other side of the turbine housing 41. The turbine housing 41 is moved axially away from the second surface 52b of the inner friction disc 5 under the pressure differential. Thereby, the lock-up clutch is released.

Of course, it is also contemplated by those skilled in the art that other driving means may be used to effect axial movement of the turbine housing 41, such as, for example, a diaphragm spring or the like.

In some embodiments of the present disclosure, referring to fig. 1, in order to limit the end point of the stroke of the axial movement of the turbine housing 41, a first limit bush 58 is provided at the first surface 52a of the outer peripheral portion 52 of the inner friction disc 5, said first limit bush 58 being annular in shape around said rotation axis X for supporting said inner friction disc 5 axially when said turbine 4 is in the locking position, thereby defining the left end point of the stroke of the turbine housing 41. Furthermore, a second limit bushing 68 is provided between said output hub 6 and said casing 2, the second limit bushing 68 being annular in shape around the rotation axis X for axially supporting the output hub 6 when the turbine 4 is in the disengaged position, thereby defining the right end point of travel of the turbine housing 41.

Referring to fig. 2 and 6, a plurality of radially extending fluid passages 69 may be provided in the second restraining bushing 68 to allow fluid to flow into or out of the second chamber 12 between the turbine housing 41 and the outer casing 2. The inflow path of the fluid is schematically shown by arrows in fig. 8. Conversely, an outflow path of the fluid can be envisaged.

Referring to fig. 1 and 4, a seal ring 56 is also provided at the first surface 52a of the outer peripheral portion 52 of the inner friction disc 5. The sealing ring 56 is annular in shape around the rotation axis X for forming a fluid seal between the pump wheel housing 31 and the inner friction disc 5 when the turbine 4 is in the locked position, thereby ensuring a pressure difference between the first chamber 11 and the second chamber 12. Thus, the inner friction discs 5 and the turbine housing 41 form a tight and firm friction-locked connection, thereby ensuring the efficiency of the torque transmission in the rigid transmission mode.

In some embodiments, referring to FIG. 7, the first stop bushing 58 and the seal ring 56 are radially continuous with one another. For example, a first stop bushing 58 is disposed radially inward of the seal ring 56 and immediately adjacent to the seal ring 56. A plurality of centering bosses 50 may be provided in the inner friction disc 5. The plurality of centering bosses 50 engage an inner peripheral surface of the first limit bushing 58 to center the first limit bushing 58 relative to the rotational axis X, and thus the seal ring 56 is centered by radial succession with the first limit bushing 58. Optionally, a first stop bushing 58 is disposed radially outward of the seal ring 56 and immediately adjacent to the seal ring 56. The plurality of centering bosses 50 engage an inner peripheral surface of the seal ring 56 to center the seal ring 56 relative to the axis of rotation X, and thus the first limit bushing 58, by radial succession with the seal ring 56.

Referring to fig. 2 to 4, the inner friction disc 5 includes an inner peripheral portion 51 on a radially inner side thereof, the inner peripheral portion 51 including a plurality of elastic member holding windows 53. The plurality of elastic member holding windows 53 extend in the circumferential direction. Adjacent two elastic member holding windows 53 are separated from each other in the circumferential direction by a radial partition portion 55. The plurality of spring members 7 are axially retained between the plurality of spring member retaining windows 53 and the pump wheel core ring 32. Referring to fig. 5, the pump wheel core ring 32 includes a plurality of drive tabs 33 extending towards the inner friction disc 5, which also forms part of the damper.

In some embodiments, as shown in fig. 2, the resilient member 7 is circumferentially disposed in series between the inner friction disk 5 and the pump wheel core ring 32. Each resilient member 7 is circumferentially compressed between the drive tabs 33 of the pump wheel core ring 32 and the radial partitions 55 of the inner friction disc 5.

In the rigid transmission mode of the torque converter 1, as shown in fig. 9, the inner friction disks 5 are engaged with the turbine housing 41. In this case, the torque input through the outer case 2, the pump impeller 3 is transmitted to the inner peripheral portion 51 of the inner friction disk 5 via the driving tabs 33 of the pump impeller core ring 32 and the elastic member 7 (not shown in fig. 9), and the outer peripheral portion 52 of the inner friction disk 5 transmits the torque to the turbine housing 41 and the output hub 6 via the locked connection between the friction plates 54 and the turbine housing 41. Therefore, fluctuations in engine torque in the rigid transfer mode can be effectively absorbed and reduced.

In a hydrodynamic transmission mode (not shown) of the torque converter 1, the inner friction discs 5 and the turbine housing 41 are disengaged. In this case, the torque input through the casing 2 is hydraulically transmitted to the turbine 4 through the pump impeller 3, and further transmitted to the output hub 6 through the turbine housing 41.

In some embodiments, as shown in fig. 3 and 4, the outer and inner

peripheral portions

52, 51 of the inner friction disk 5 are connected by a plurality of radial webs 57. Circumferentially extending fluid communication windows 59 are formed between adjacent radial webs 57 to allow fluid circulating inside the first chamber 11 for hydraulic transmission to pass through, while reducing the weight of the inner friction discs 5 and the entire torque converter 1.

Referring to fig. 3, each radial web 57 is radially aligned with a corresponding radial partition 55 of the inner peripheral portion 51, thereby enhancing the mechanical strength of the inner friction disc 5 as a torque transmitting member.

Further, referring to fig. 1, the constituent parts of the shock absorber (the pump wheel core ring 32, the elastic member 7, and the elastic member holding window 53) are located at the intermediate positions in the radial direction of the first chamber 11 without occupying the fluid transmission path of the hydraulic drive between the pump wheel 3 and the turbine wheel 4. Thus, the torque converter 1 according to the present disclosure makes full use of the inner space of the first chamber 11 at the radial middle position to arrange the damper, greatly reduces the size of the torque converter 1 in the radial direction, and is compact in structure so as to be suitable for various application environments.

Various modifications, changes, and variations may be implemented with the above-described embodiments.

In accordance with the provisions of the patent statutes, the foregoing description of exemplary embodiments of the present disclosure has been presented for the purpose of illustration. It is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. The embodiments disclosed above were chosen in order to best explain the principles of the disclosure and its practical application to thereby enable others skilled in the art to best utilize the disclosure in various embodiments and with various modifications as are suited to the particular use contemplated, as long as the principles described herein are followed. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains. Accordingly, changes may be made in the above disclosure without departing from the intent and scope of the disclosure. It is also intended that the scope of the disclosure be defined by the claims appended hereto.

Claims

1. A torque converter, comprising:

a housing (2) arranged about a rotation axis (X) for receiving an input torque;

a pump wheel (3) arranged about the axis of rotation (X) and comprising a pump wheel housing (31), a pump wheel core ring (32) and a plurality of pump wheel blades (34);

a turbine wheel (4) disposed axially opposite the pump wheel (3) about the axis of rotation (X), the turbine wheel (4) comprising a turbine housing (41) and a plurality of turbine blades (43);

an output hub (6) disposed about the axis of rotation (X) and fixedly connected to the turbine housing (41) for outputting a torque;

wherein, this torque converter still includes: an inner friction disc (5) arranged around said rotation axis (X) and axially interposed between said pump wheel (3) and said turbine wheel (4), a plurality of elastic members (7) being arranged on said inner friction disc (5), said plurality of elastic members (7) being held between said inner friction disc (5) and said pump wheel core ring (32) to transmit torque from said pump wheel (3) to said inner friction disc (5) via said plurality of elastic members (7); and wherein

The turbine wheel (4) is axially displaceable between a locking position in which the turbine housing (41) engages and forms a locking connection with the inner friction disc (5), and a disengaged position in which the turbine housing (41) is disengaged from the inner friction disc (5).

2. A hydrodynamic torque converter as defined in claim 1, wherein said inner friction disk (5) is annular in shape, said inner friction disk (5) including an inner peripheral portion (51) located radially inward thereof, said inner peripheral portion (51) including a plurality of elastic member retaining windows (53), said plurality of elastic member retaining windows (53) extending circumferentially, adjacent two elastic member retaining windows (53) being circumferentially separated from each other by a radial partition (55), said plurality of elastic member being axially retained between said plurality of elastic member retaining windows (53) and said pump wheel core ring (32).

3. A hydrodynamic torque converter according to claim 2, characterized in that said pump wheel core ring (32) comprises a plurality of driving tabs (33) extending towards said inner friction disc (5).

4. A hydrodynamic torque converter according to claim 2 or 3, characterized in that the inner friction disc (5) comprises an outer peripheral portion (52) on the radially outer side thereof, the outer peripheral portion (52) comprising a first surface (52a) facing the pump wheel (3) and a second surface (52b) facing the turbine wheel (4), the second surface (52b) being provided with friction discs (54) for forming a locking connection with the turbine housing (41).

5. A hydrodynamic torque converter according to claim 4, characterized in that a first limit bushing (58) is provided at the first surface (52a) of the peripheral portion (52) of the inner friction disc (5), said first limit bushing (58) having an annular shape around the rotation axis (X) for axially supporting the inner friction disc (5) when the turbine wheel (4) is in the locking position.

6. A hydrodynamic torque converter as claimed in claim 5, characterized in that said inner friction disc (5) is provided with a sealing ring (56) at the first surface (52a) of the peripheral portion (52).

7. A hydrodynamic torque converter according to claim 6, characterized in that a plurality of centering bosses (50) are provided in the inner friction disc (5) for centering the sealing ring (56) and/or the first limit bushing (58) with respect to the rotation axis (X).

8. A hydrodynamic torque converter as claimed in claim 4, characterized in that the outer peripheral portion (52) and the inner peripheral portion (51) of the inner friction disc (5) are connected by a plurality of radial webs (57), adjacent radial webs (57) forming circumferentially extending fluid communication windows (59) therebetween.

9. A hydrodynamic torque converter according to claim 9, characterized in that each radial web (57) is radially mutually aligned with a respective radial partition (55) of the inner peripheral portion (51).

10. A hydrodynamic torque converter according to claim 5, characterized in that a second limit bushing (68) is provided between the output hub (6) and the casing (2), the second limit bushing (68) being annular in shape around the rotation axis (X) for axially supporting the output hub (6) when the turbine wheel (4) is in the disengaged position.

11. A hydrodynamic torque converter according to claim 7, characterized in that a plurality of radially extending fluid passages (69) are provided in the second limit bushing (68) to allow fluid to flow into or out of the space between the turbine housing (41) and the outer shell (2).

12. A motor vehicle characterized in that it comprises a torque converter according to any one of claims 1 to 11.