DE102006042441B4 - Hydrodynamic torque converter with a lock-up clutch - Google Patents

Abstract

A hydrodynamic torque converter (1) having a lock-up clutch (8) for frictionally coupling converter pump blades (35) to converter turbine blades (37), said lock-up clutch (8) having inner and outer clutch plates (55, 56, 56a) serving as clutch plates (55). with friction lining (59) and those without friction lining, wherein at least one coupling plate is designed such that flow channels form, which come from a space (100) between converter pump blades (35) and converter turbine blades (37) operating fluid flow radially inward or outward can be cooled so that the engaged lock-up clutch (8) is cooled, characterized in that the at least one clutch plate comprises two rotatably fixed to each other arranged fin parts (400, 401) which are spaced apart by means of a plurality of nubs (402a, 402b, 402c) (56 , 56a) radially and circumferentially spaced from each other in at least one fin part (400, 401) are pressed.

Description

The invention relates to a hydrodynamic torque converter with a lockup clutch according to the patent claim 1.

From the DE 102 33 335 A1 is a hydrodynamic torque converter with a lock-up clutch known. The lock-up clutch has clutch plates, which can be engaged by an axial piston. It is intended to direct a targeted leakage from a piston chamber of the lock-up clutch by means of bores to the clutch plates.

There are non-generic wet starting clutches in which operating fluid or oil is between the clutch plates when starting. These wet starting clutches differ fundamentally from lockup clutches, since in wet start clutches a speed difference for the operating fluid flow is inherently necessary.

In addition, from the DE 103 50 935 A1 as well as the DE 197 22 151 A1 Clutch fins for a lockup clutch of a hydrodynamic torque converter are known in which flow channels are provided, which guide a coming from a space between converter pump blades and converter turbine blades radially inward operating fluid flow, so that the lock-up clutch is coolable in an engaged state.

The object of the invention is to provide for high torque a particularly fail-safe hydrodynamic torque converter with lock-up clutch.

This object is achieved with the features of claim 1.

A lock-up clutch increases the efficiency of the hydrodynamic torque converter, since the impeller and the turbine wheel can be frictionally coupled with each other in many driving conditions, so that the hydraulic losses are minimized. In this case, the lockup clutch can also be adjusted to a specific friction torque, so that torque shocks are not forwarded even when coupling impeller and turbine. Furthermore, with a low slip damping for a resilient torsional damper can be achieved. However, especially these functions cause a thermal load on the clutch plates even with closed or at least almost closed lock-up clutch. This load increases with the height of the torque to be transmitted.

In this case, an internal cooling is provided in the inner clutch plates or the outer clutch plates. For this purpose, flow channels are provided which direct the operating fluid of the hydrodynamic torque converter from the space between the converter pump blades and the converter turbine blades radially inwardly or outwardly through the lock-up clutch. In this case, the clutch plates are cooled with the flow channels of the operating fluid.

According to the invention, the internally cooled clutch plate consists of two Lammellenteilen and the flow channels are formed by at least one of the two Lammellenteile is provided with nubs, which are pushed out of the plate of the disk part. The nubs are on the other lamella part. This forms a permeable space. In a particularly advantageous manner, the two lamella parts associated with a clutch disk are provided with nubs. In this case, the knobs abut each other, so that there is a very wide flow channel, which has a correspondingly low flow loss. Consequently, an oil pump only has to build up a low internal converter pressure.

Other clutch plates form the friction partner and can be provided with a friction lining. This friction lining can be designed with or without grooves. The flow channels according to the invention have the advantage over an alternative solution with particularly deep grooves in the friction lining that thin friction linings can be used. This saves axial space and expensive friction lining material. In a particularly advantageous embodiment of the invention can even be dispensed with entirely grooves in Rebbelag, which is associated with a corresponding increase in the surface pressure and the mechanical strength of the friction lining.

In one embodiment, in which recesses are provided in an outer and / or an inner plate carrier, the operating fluid can be conducted with only slight flow losses to the cooled clutch plates - or away from them.

In a particularly advantageous embodiment of the invention, the clutch plates are made with the flow channels of a good heat conductor - such as steel - so that they can absorb a large part of the heat from the operation of the lock-up clutch and can return to the operating fluid. The friction lining on the other clutch plates is a relatively good insulator, so that this and the fixedly connected with this other clutch plates are kept free of thermal stress.

Further advantages of the invention will become apparent from the other claims, the description and the drawings.

The invention is explained below with reference to several embodiments.

Showing:

1 a drive arrangement with a hydrodynamic torque converter with a lock-up clutch,

2 a detail of the lock-up clutch 1 which comprises an outer and an inner plate carrier,

3 an outer plate carrier in a first embodiment,

4 an outer plate carrier in a further embodiment,

5 an inner plate carrier in a first embodiment,

6 an inner plate carrier in a second embodiment,

7 a partial region of a disk part of a clutch disk in a perspective view,

8th a clutch plate according to 7 in a plan view and

9 a plan view of a clutch plate in a second embodiment.

1 shows a drive assembly with a hydrodynamic torque converter 1 , the input side via a diagonal screw connection 19 is connected to a non-illustrated partially flexible drive plate and a crankshaft of a drive motor.

On the output side is the hydrodynamic torque converter 1 via a splined shaft 52 connected to a coaxially arranged transmission input shaft of a transmission, not shown. The transmission input shaft, the hydrodynamic torque converter 1 and a crankshaft flange are coaxial with a central axis 25 arranged.

The hydrodynamic torque converter 1 includes the housing 5 , a pump 35 , a turbine wheel 37 and a stator 38 ,

The following detailed description of the embodiment follows the power flow from the crankshaft to the housing 5 , From the case 5 the power flow is directed to the impeller 35 , In hydrodynamic power transmission, the power flow from the impeller 35 on the turbine wheel 37 and a torsion damper 7 transferred to the said transmission input shaft. On the other hand, the power flow is at an engaged lock-up clutch 8th from the case 5 via the lock-up clutch 8th on the torsion damper 7 and then transferred to the transmission input shaft.

The turbine wheel 37 is next to the impeller 35 arranged on the drive motor side facing the. Axial between the impeller 35 and the turbine wheel 37 is the stator 38 arranged radially inside, which in the usual way to a freewheel 39 supported.

An inner hub 40 of the freewheel 39 is rotatably connected by means of an internal gear with a stator shaft, not shown.

• – des Stützblechs 46,
• – des Federträgers 44 und
• – eines drehfest mit letzterem vernieteten Kupplungsbleches 53

eingearbeitet sind.The turbine wheel 37 is via a carrier ring 43 rotatably with a spring carrier 44 connected, which is against the torsional stiffness of the torsion damper 7 limited rotatable to a support plate 46 is arranged. These are bow springs 47 . 14 of the damper 7 in recesses 48 taken in the sheet

• - the support plate 46 .
• - the spring carrier 44 and
• - A non-rotatably riveted with the latter coupling plate 53

are incorporated.

The spring carrier 44 is with the coupling plate 53 immovable connected.

The support plate 46 is radially outside the bow springs 47 . 14 in the circumferential direction with curved lugs 49 provided, which the bow springs 14 to lead. The support plate 46 is radially inside against rotation with a socket 51 connected is. This socket 51 is by means of the aforementioned spline 52 rotatably connected to the transmission input shaft.

The coupling plate 53 is resistant to movement with an inner plate carrier 54 connected. The inner plate carrier 54 holds inner clutch plates via an axial toothing 55 the lockup clutch 8th which in detail according to 2 can be seen. These clutch plates 55 are rotatably and axially displaceable relative to the inner plate carrier 54 , Likewise, outer clutch plates 56 at one with the housing 5 firmly connected outer plate carrier 57 rotatably supported and axially displaceable. This is an axially aligned internal toothing 13 in the outer plate carrier 57 incorporated into which outer teeth 405 the outer clutch plates 56 intervention. The outer plate carrier 57 extends coaxially with the housing 5 and is friction welded to this motion resistant. The outer and inner clutch plates 56 . 55 engage radially with each other.

Here are the inner clutch plates 55 friction linings 59 on, which are firmly attached to both sides of a body. These friction linings 59 lie on both sides of the outer clutch plates 56 and on one side of the frontmost clutch plate 56a and an abutment disc 63 at. In this case, a friction torque is transmitted to the contact surfaces.

In 2 it can be seen that the outer clutch plates 56 . 56a each of two fin parts 400 . 401 put together. These two lamella parts 400 . 401 have pimples facing each other 402a to c and 403 on. Here are the plateaus 404 the pimples 402a to c and 403 to each other, so that the two lamella parts 400 . 401 support each other.

7 shows a partial view of the fin part in a perspective view 200 in a first embodiment. It can be seen that the knobs are pressed from one side in the deep drawing process in the plate of the fin part. In 8th it can be seen that in the circumferential positions of the teeth 405 two pimples each 402a are arranged radially one above the other. In the circumferential positions of the interdental spaces 406 are also two pimples each 402b arranged radially one above the other. In a position that is both radially and circumferentially between the two knobs 402a and the two pimples 402b is lying, are more pimples 402c arranged.

According to 1 is an axial piston 58 at its periphery in the outer disc carrier 57 and at its central hole 60 on a cone 61 axially guided. This pin 61 is resistant to movement with the housing 5 caulked. The lockup clutch 8th is through the on its outside 62 hydraulically pressurizable axial piston 58 engageable. This is due to the axial piston 58 arranged annular shoulder 32 at the frontmost clutch plate 56a the outer clutch plates 56 at. With disengaged axial piston 58 and engaged lock-up clutch 8th are based on the frictionally interconnected clutch plates 55 . 56a . 56 over the abutment disc 63 on a circlip 64 from. This circlip 64 is in an inner peripheral groove of the outer disc carrier 57 engaged. It is between the abutment disc 63 and the circlip 64 a clearance 68 provided that is also referred to as KÜB game. The abutment disc 63 is particularly thick, because it is exposed to a high bending load.

The housing 5 , the outside 62 of the axial piston 58 , the outer plate carrier 57 and the pin 61 close a pressurized space that can be filled with operating fluid 66 one. For supply with operating fluid or pressure, the hollow-drilled pin 61 several cross holes 3 in the wall, which are connected in a manner not shown via a central longitudinal bore in the transmission input shaft with a valve which is controlled by a transmission control. If the valve now releases hydraulic pressure, this hydraulic pressure is transmitted through the longitudinal bore and the transverse bores 3 to the axial piston 58 passed so that the clutch plates 55 . 56 frictionally abut each other and a torque corresponding to the hydraulic pressure from the housing 5 on the torsion damper 7 transfer.

• – dem Turbinenrad 37 und
• – dem Pumpenrad 35 bzw. dem Gehäuse 5

bildet. Der Druck an diesem Spalt 101 nimmt infolge der Zentrifugalkraft im Betrieb des Drehmomentwandlers 1 bei hohen Drehzahlen zu. Dieser Druck an dem Spalt 101 steigt mit der Pumpenraddrehzahl und ist auch von der Turbinenraddrehzahl und damit der Last abhängig. Dieser Druck am Spalt 101 ist bei eingerückter bzw. geschossener Überbrückungskupplung 8 am höchsten, da dann das Turbinenrad 37 und das Pumpenrad 35 die gleiche Drehzahl aufweisen. Die Spaltbreite des Spaltes 101 ist ebenfalls nicht konstant, da der Drehmomentwandler 1 elastisch ist und sich bei hohem Innendruck aber auch bei hoher Differenzdrehzahl zwischen dem Turbinenrad 37 und dem Pumpenrad 35 das Gehäuse 5 gegenüber dem Turbinenrad 37 aufweitet. Das aus diesem Spalt 101 je nach Betriebszustand in unterschiedlichen Volumenströmen austretende Betriebsfluid wird genutzt, um die Überbrückungskupplung 8 zu kühlen. Dabei wird das Betriebsfluid durch Ausnehmungen im äußeren Lamellenträger 57 entlang den Kupplungslamellen 55, 56, 56a radial nach innen geleitet. Ebenso könnte das Betriebsfluid in einer weiteren Ausführungsform durch die Ausnehmungen radial von innen nach außen geleitet werden.During operation of the hydrodynamic torque converter 1 The operating fluid circulates in one of the impeller 35 , the turbine wheel 37 and the stator 38 enclosed hydraulic working space 100 , The internal pressure in this workspace 100 is applied by an oil pump, not shown, which is driven by the internal combustion engine drive motor. This internal pressure prevents cavities and air bubbles. The pressure applied by the oil pump is regulated. As a result of the internal pressure operating fluid flows from a gap 101 that is between

• - the turbine wheel 37 and
• - the impeller 35 or the housing 5

forms. The pressure on this gap 101 decreases due to the centrifugal force during operation of the torque converter 1 at high speeds too. This pressure at the gap 101 increases with the impeller speed and is also dependent on the turbine speed and thus the load. This pressure at the gap 101 is with engaged or shot lock-up clutch 8th highest, then the turbine wheel 37 and the impeller 35 have the same speed. The gap width of the gap 101 is also not constant because of the torque converter 1 is elastic and at high internal pressure but also at high differential speed between the turbine wheel 37 and the impeller 35 the housing 5 opposite the turbine wheel 37 expands. That's out of this gap 101 depending on the operating state in different flow rates exiting operating fluid is used to the lock-up clutch 8th to cool. In this case, the operating fluid through recesses in the outer plate carrier 57 along the clutch plates 55 . 56 . 56a directed radially inwards. Likewise, the operating fluid could be passed in a further embodiment through the recesses radially from the inside to the outside.

Two alternative embodiments of these recesses are in 3 and 4 seen. From the clutch plates 55 . 56 . 56a the operating fluid flows back into the operating fluid circuit, which finally returns to the working space via the oil pump 100 leads. This way from the lockup clutch 8th back into the operating fluid circuit runs with a very low differential pressure over the freewheel 39 back through the aforementioned stator shaft. Further, operating fluid flows along a thrust bearing 103 , which is about a disc 104 on the one hand on a bearing outer ring 105 of the freewheel 39 and on the other hand on the carrier ring 43 supported. Further, operating fluid flows through another thrust bearing 106 along the spline 52 ,

3 shows in a first alternative embodiment, the outer plate carrier 57 , The plate carrier 57 is a deep-drawn part made of sheet steel. In the tooth grounds between two teeth 111 are the recesses 110 punched in the form of narrow grooves, while maintaining sufficient strength of the disc carrier 57 allow sufficient for cooling operating fluid flow.

In the embodiment according to 4 are some recesses 212 at regular intervals formed larger than the other recesses 210 , In this case, the larger recesses extend 212 up to a receiving groove 213 for the circlip 64 over much of the tooth base between the two teeth 211 ,

5 and 6 show the inner plate carrier 54 , This is for Betriebsfluidabfuhr also with recesses 300 executed. According to 5 is only in every second tooth base between two teeth 310 . 311 one of the recesses 300 punched in the form of a rounded groove. This results in a relatively high strength of the disk carrier 54 reached. According to 6 is in every tooth between two teeth 312 . 313 a recess 301 punched in the form of a groove, which is opposite to the embodiment 5 causes a doubling of the flow cross-section and is particularly advantageous if only a small pressure is available.

9 shows in a further embodiment, a fin part 500 in a representation analog 8th , Here are in the circumferential positions of the outer teeth 1405 three pimples each 1402a arranged radially spaced from each other, so that these three nubs 1402a one unity 1000 form. Circumstance between these units 1000 of three pimples 1402a is another unit 1001 of three pimples 1402b arranged radially spaced from each other. Circumstance between this one unit 1001 of pimples 1402b and the other unit 1000 of pimples 1402a are units 1002 of two pimples 1402c arranged radially offset between the nubs 1402a . 1402b the other two units 1000 . 1001 are arranged.

The clutch plates can also be composed of more than just two fin parts. In particular, three blade parts can be provided.

The described embodiments are only exemplary embodiments. A combination of the described features for different embodiments is also possible. Further, in particular not described features of the device parts belonging to the invention are to be taken from the geometries of the device parts shown in the drawings.

Claims (4)

Hydrodynamic torque converter ( 1 ) with a lock-up clutch ( 8th ) for the frictional coupling of converter pump blades ( 35 ) with converter turbine blades ( 37 ), this lock-up clutch ( 8th ) inner and outer clutch plates ( 55 . 56 . 56a ), which as clutch plates ( 55 ) with friction lining ( 59 ) and those are designed without friction lining, wherein at least one coupling plate is formed such that flow channels form, which one from a space ( 100 ) between converter pump blades ( 35 ) and converter turbine blades ( 37 ) leading radially inward or outward flow of operating fluid, so that the engaged lock-up clutch ( 8th ) Can be cooled characterized in that the at least one clutch plate two rotatably arranged mutually slat parts ( 400 . 401 ) by means of a plurality of pimples ( 402a . 402b . 402c ) are spaced from each other ( 56 . 56a ), which are radially and circumferentially spaced apart in at least one fin part ( 400 . 401 ) are pressed. Hydrodynamic torque converter according to claim 1, characterized in that at least a part of the operating fluid flow in the region of a bearing inner ring ( 40 ) of a freewheel ( 39 ). Hydrodynamic torque converter according to one of the preceding claims, characterized in that in the plate carrier ( 57 . 157 . 54 ) of the clutch plate ( 56 . 56a ) With Flow channels recesses ( 110 . 212 . 300 . 301 ) are provided. Hydrodynamic torque converter according to one of the preceding claims, characterized in that the two slat parts ( 400 . 401 ) are configured identically, wherein two flow channel parts are arranged opposite one another such that a common flow channel is formed.

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