Hydrodynamic torque converter

A hydrodynamic coupling arrangement (1), comprising an impeller (6) linkable to a drive shaft, a turbine (7) linkable to a driven shaft via a hub (11) and able to hydrodynamically coupled with the impeller (6), a lockup clutch (20) able to short-circuited the hydrodynamically coupling between the impeller (6) and the turbine (7), a torsional vibration damper arrangement (13;14,15) located between the lockup clutch (20) and the hub (11), said torsional vibration damper arrangement comprising an input element (16;17,47,24), an output element (17; 25,33,32) and a plurality of elastic elements (22;26) disposed between the input element and the output element, the output element of the torsional vibration damper arrangement forms a part of the hub, wherein the coupling arrangement comprises an absorber device (29) being linked in rotation to the hub, said absorber device comprising a unique resonance frequency.

This application is a national stage application of International Application No. PCT/IB2015/000527 filed Mar. 11, 2015, the disclosure of which is incorporated herein by reference and to which priority is claimed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to hydrodynamic coupling arrangement.

2. Description of the Related Art

Generally, vehicles with automatic transmissions are equipped with a hydrokinetic torque coupling device for fluidly coupling the driving shaft of an engine to a driven shaft of a transmission.

It is known a hydrodynamic torque converter comprising an impeller, a turbine and a lockup clutch. Lockup clutches are known for mechanically coupling the driving and driven shafts under certain operating conditions. Lockup clutches and their operation are described in, for example, U.S. Pat. Nos. 8,276,723 and 7,191,879.

The hydrodynamic torque converter may comprises also a torsional vibration damper arrangement which is located between the lockup clutch and a hub connected to a transmission shaft. Such hydrodynamic torque converter is described in the DE 10 2014213 606 A1. The vibration damper arrangement forms an input element, an output element and elastic organs which are disposed between the input element and the output element of the torsional vibration damper arrangement.

The hub forms a piece on which the turbine is connected for transmission of the torque from the engine side to the transmission side. The hub forms a cylindrical inner part which is intended to be directly connected to the transmission shaft and a cylindrical outer part which forms a disk element. The disk element extends radially with regard to the rotation axis of the transmission shaft. The disk of the hub forms the output element of the torsional vibration damper arrangement. The turbine is connected to this central disk element.

Even such hydrodynamic torque converter provides satisfactory results, it needs to improve performance, in particular to absorb more vibrations.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to provide a hydrokinetic torque coupling device which present better damping vibration performance.

The object of the invention is to provide a hydrodynamic coupling arrangement, comprisingan impeller linkable to a drive shaft,a turbine linkable to a driven shaft via a hub and able to hydrodynamically coupled with the impeller,a lockup clutch able to short-circuited the hydrodynamically coupling between the impeller and the turbine,a torsional vibration damper arrangement located between the lockup clutch and the hub, the torsional vibration damper arrangement comprising an input element, an output element and a plurality of elastic elements disposed between the input element and the output element, the output element of the vibration damper arrangement formed integrally with the hub. The term “integral” (or “integrally”) relates to a part made as a single part, or a part made of separate components fixedly (i.e., non-moveably) connected together.

The hydrodynamic coupling arrangement further comprises—an absorber device being non-moveably connected to the hub, the absorber device comprising a unique resonance frequency.

In an embodiment of the invention, the absorber device is linked to the output element of the vibration damper arrangement.

In an embodiment of the invention, the absorber device and the turbine are connected together.

In an embodiment of the invention, the absorber device is located between the vibration damper arrangement and the turbine.

In an embodiment of the invention, the absorber device comprises a primary component, a secondary component and a plurality of elastic organs located between the primary component and the secondary component in such a way that it is generated a force which is contrary to the rotation of the secondary component with regards to the primary component.

In an embodiment of the invention, the secondary component links the primary component to the hub.

In an embodiment of the invention, the vibration damper arrangement comprises two dampers which are positioned in series one with regards to the other.

In an embodiment of the invention, the primary component is located axially between one of the dampers and the turbine.

In an embodiment of the invention, the secondary component is formed by two plates linked together to define at their external periphery a circumferential housing for receiving the elastic organs, one of these two plates being linked to the hub.

In an embodiment of the invention, each of the plates of the secondary component comprises tabs, an elastic organ being located circumferentially between the said tabs, the primary component comprises openings able to receive the elastic organ, the primary component and the secondary component cooperate the one with the other with the elastic organ being intended to be compressed between the two components.

In an embodiment, each plates comprises at its external periphery radial tabs and axial tabs, the two plates of the secondary component are arranged with a same elastic organ which is located circumferentially between two sets of radial tabs and two axial tabs.

In an embodiment of the invention, the hub forms a one piece design.

In an embodiment of the invention, the hub comprises four parts, the first one is formed by a central part which is intended to be connected to the driven shaft, the second part and the fourth part extends radially with regards to the first part and being spaced apart axially one from the other, at least the fourth part forming the outpart element of the torsional vibration damper arrangement.

In an embodiment of the invention, the absorber device is linked to the second part of the hub.

In an embodiment of the invention, the turbine is linked to the second part of the hub.

In an embodiment of the invention, the torsional vibration damper arrangement comprises a first damper and a second damper which are disposed in series one with regards to the other and which acts in series to transmit torque.

In an embodiment of the invention, the first and the second dampers are positioned radially one inside the other.

In an embodiment of the invention, each damper is formed by at least one guiding ring, a flange and a phasing member, a plurality of springs being disposed between the guiding ring and the flange, the phasing member being rotationally free placed between at least two springs.

In an embodiment of the invention, the first damper comprises one guiding ring and a first flange, the second damper comprises two guiding rings and a second flange, the first flange forming one of the two guiding rings of the second damper.

In an embodiment of the invention, there is a stator between the impeller and the turbine.

Another object of the invention is to provide a hydrodynamic coupling arrangement, comprisingan impeller linkable to a drive shaft,a turbine linkable to a driven shaft via a hub and able to hydrodynamically coupled with the impeller,a lockup clutch able to short-circuited the hydrodynamically coupling between the impeller and the turbine,a torsional vibration damper arrangement located between the lockup clutch and the hub, said torsional vibration damper arrangement comprising an input element, an output element and a plurality of elastic elements disposed between the input element and the output element, the output element of the vibration damper arrangement is linked to the hub,an absorber device being linked in rotation to the hub, said absorber device comprising a unique resonance frequency, wherein the hub and the output element of the damper arrangement form a one piece design, i.e., formed integrally with one another.

In an embodiment of the invention, the absorber device is linked to the output element and to the turbine together.

An other object of the invention is to provide a hydrodynamic coupling arrangement, comprisingan impeller linkable to a drive shaft,a turbine linkable to a driven shaft via a hub and able to hydrodynamically coupled with the impeller,a lockup clutch able to short-circuited the hydrodynamically coupling between the impeller and the turbine,a torsional vibration damper arrangement located between the lockup clutch and the hub, said torsional vibration damper arrangement comprising an input element, an output element and a plurality of elastic elements disposed between the input element and the output element, the output element of the vibration damper arrangement is linked to the hub, the damper comprising two dampers units which are disposed in series one with regards to the other and which acts in series to transmit torque,an absorber device being linked in rotation to the hub, said absorber device comprising a unique resonance frequency and an inertial mass, wherein the inertial mass being axially located in regards to the damper which is the farthest from the rotation axis of the hydrodynamic coupling arrangement.

The absorber device comprises two components and elastic organs between the two components, one of the components forms the inertial mass and the other component links the inertial mass to the hub.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

FIG. 1shows a hydrodynamic coupling arrangement1constructed as a hydrodynamic torque converter. The coupling arrangement1comprises a housing arrangement2with a first carter3and a second carter4. The first carter3is to be connected on the drive side, i.e. facing a drive unit, and therefore for rotation together therewith and a second carter4which is to be positioned on the driven side, i.e., facing a transmission. The two carters3,4are fixedly (i.e., non-moveably) connected to one another in their radially outer area by welding or by other fixing means. A plurality of impeller blades5arranged consecutively around an axis of rotation X are provided at an inner side of the second carter4so that the carter4with these impeller blades5form an impeller6. A turbine7having turbine blades8which are positioned so as to face the impeller blades4is provided in an interior space9of the housing arrangement2.

The turbine7comprises a turbine shell10which is fixedly (i.e., non-moveably) connected in its radially inner area, for example, by riveting, to a hub11.

A stator12is positioned between the impeller6and the turbine7. The stator12is supported on a hollow shaft (not illustrated) so as to be rotatable in one direction around the axis of rotation X.

A torsional vibration damper arrangement13comprises two torsional vibration dampers14,15which are positioned radially one inside the other and which act in series to transmit torque between the housing arrangement2and the transmission.

The radially outer torsional vibration damper14which is the first torsional vibration damper in the torque path comprises a guiding ring16which forms the input of the torsional vibration damper arrangement13. The input of this first torsional vibration damper is connected to a piston18which comprises a friction area19. This friction area19forms a plate or a driven-side of a lockup clutch20. The housing arrangement2in its interior face forms locally an another friction area21or a drive-side. The piston18presses the two friction areas19and21into mutual frictional engagement to engage the lockup clutch20so that direct torque transmission coupling is produced between the housing arrangement2and the torsional vibration damper arrangement13.

The first torsional vibration damper14comprises also a flange17or the outpart of this first torsional vibration damper14. Damper elements22act between the guiding ring16and the flange17. These dampers elements can form helicoïdal compression springs or the like which are consecutively arranged in circumferential direction. A phasage member23could be inserted between two damper elements and freely rotative between these two damper elements. Such a torsional vibration damper14with the phasage member23is usually named LTD (or Long Travel Damper). In this example, the damper elements are disposed on a same diameter but it could be considered that the damper elements could be on a different diameter.

The second torsional vibration damper15comprises a guiding ring47and a cover disk24which are fixedly connected to one another by riveting or the like. The guiding ring47is the same piece as the flange17of the first torsional vibration damper14. Another flange25forms the output of the second torsional vibration damper15. The guiding ring47and the cover disk24are rotatable with respect to the flange25against the action of a second damper elements26. As for the first damper element22, the second damper element26can form helicoïdal compression springs or the like which are consecutively arranged in circumferential direction. In the example according toFIG. 1, the second damper element26is bigger than the first damper element22. A phasage member28is provided also for this second torsional vibration damper15to form another LTD. As for the first torsional vibration damper14, in this example, the damper elements are disposed on a same diameter but it could be considered that the damper elements could be on a different diameter.

The flange25forms a part of the hub11. The hub11forms a one piece design.

According to the invention, in addition to the torsional vibration arrangement13, it is foreseen an absorber device29. This absorber device29may be constructed for example as fixed frequency mass dampers and is not generally located in the torque path but rather are coupled to torque transmitting component assemblies and accordingly receive torsional vibrations and suppress them by generating a counter vibration of the torsional vibration absorber.

The absorber device29is linked in rotation to the hub11on which the turbine10is intended to be connected. The absorber device29is also connected to the output of the torsional vibration arrangement13.

In the illustrated exampleFIG. 1, the hub11comprises four parts. The first part30forms a cylindrical element which is intended to be directly connected, via inner teeth44, to the transmission shaft (no illustrated). The fourth part is formed by the flange25of the second torsional vibration damper15. The second part32and the flange25extend radially with regards to the first part30and each forms circular plane part. The second part32and the flange25are axially spaced apart by the third part33. InFIG. 1, the third part33extends axially between the two parts32and25. The second part32is the part on which are connected together the turbine10and the absorber device29. The second part32, the third part33and the flange25form the output of the torsional vibration arrangement13.

FIG. 2, the absorber device29comprises a primary component34, a secondary component35, and a plurality of elastic organs (or components)36located between the primary component34and the secondary component35in such a way that it is generated a force which is contrary to the rotation of the secondary component35with regards to the primary component34.

The primary component34and the secondary component35present complementary forms such as to define between them housings37for receive the elastics organs36which can be right springs as illustrated.

The primary component34forms an inertial mass which extends axially with regard to the rotation axis X and a part which extends radially with regard to this same axis. The inertial mass is located radially outside of the elastics organs36. In the example, the inertial mass is axially aligned with regards to the damper element22. The primary component34comprises also openings27being intended to receive at least one elastic organ36.

FIG. 3, the secondary component35is formed by a first plate38and a second plate39which are connected the one to the other.

The first plate38as the second plate39forms at its external periphery an annular ring48,49with radial tabs40and axial tabs41. The radial tabs40extend radially outward whereas the axial tabs extend radially and axially outward. The radial tabs40of the two plates are superimposed together in such a way that circumferentially between them are inserted the elastic organs36, such as springs. The axial tabs41maintain axially the springs36.

The annular rings48and49of respectively the first plate38and second plate39are disposed the one with regards to the other to define between them a space50in which is located the radial part of the primary component34. In the example, the radial part of the primary component fills all the space50. But it could be considered that it fills only a part of the space50.

The first plate38presents a central annular part42comprising windows43to clear space near the springs26of the second torsional vibration damper15. This first plate38is fixedly connected at the inner area of the central annular part42to the second part32of the hub11. The turbine10is also fixedly connected at its inner area near the rotation axis X to the second part32of the hub11. The first plate38and the turbine10are fixedly connected together to the second part of the hub11.

In the example, six springs36are angularly disposed between the primary component34and the secondary component35. A sole spring modeling the whole springs36of the absorber device29forms for example a angularly stiffness coefficient is comprised between 0.36 and 36 Nm/°. In a preferred embodiment, the stiffness coefficient is 2.3 Nm/°. Each radial tab40defines two opposite radials faces45. Each opening27comprises also two radial faces46. The primary component34and the secondary component35cooperate together in such a way that each spring36is located between a radial face45and a radial face46.

The primary component34is rotative with regards to the secondary component35with a limited rotative movement due to the presence of the springs36. The rotation range of the primary component34with regards to the secondary component35is in this example comprised between 10° and 18°. In a preferred embodiment, the rotation of the primary component34with regards to the secondary component35is of 14°.

As illustrated in theFIGS. 1 to 3, the primary component34extends radially outwardly with regard to the secondary component35. The primary component34defined a mass which presents for example an inertia comprises between 0.0013 and 0.1335 kg·m2. In a preferred embodiment, the inertia of the primary component mass is 0.021 kg·m2.