DE19920661A1 - Clutch for road vehicle has electric generator linked to magnetic counterbalance minimizing manual forces and has spring maintaining clutch engagement, linked as required to disengagement unit - Google Patents

Abstract

The clutch for a road vehicle has a spring (28) maintaining clutch engagement and linked as required to a disengagement unit (32,42,48) which also partly compensates for the disengagement force. The disengagement unit converts engine torque into clutch disengagement energy. The disengagement unit incorporates a generator which converts rotational energy into electrical energy, and a magnetic force generation unit which transforms electrical energy from the generator into clutch disengagement force.

Description

The present invention relates to a coupling device, in particular Friction clutch for a motor vehicle, in which by the contact pressure of a force accumulator, a clutch state can be produced, comprising a Releaser, through which one can selectively apply the contact pressure of the force memory at least partially compensating disengagement force can be generated, wherein the releaser has an energy conversion arrangement for conversion of rotational energy of the clutch device in disengagement energy.

The internal combustion engines used in modern motor vehicle construction, which have ever increasing torques require the Use of appropriately dimensioned coupling devices, which can transmit such large torques. This ultimately means that the engaging force generated in the clutches with the torques must increase, which leads to the problem that also the disengagement such couplings correspondingly large forces are required. Around to be able to generate such forces when actuated by a driver, can be provided lever arrangements, but the disadvantage have that by the power transmission a corresponding way down Settlement is generated, which is a relatively large release path of a pedal brings with it. Servo systems can also be used however, lead to relatively expensive coupling systems.

EP 0 635 653 A2 discloses a coupling device in which the release force required to disengage the clutch directly Converting the rotational energy of the clutch into a disengagement energy becomes. For this purpose, a shear fluid coupling is provided, which is an electrorheolo contains liquid. When an electrical field is applied, the  Viscosity of this liquid changed so that a coupling Fluid coupling output component to the clutch housing. The Fluid clutch output component then drives a release component on, which acts on the lift mechanism to disengage.

It is the object of the present invention to provide a coupling device to provide, in which the conversion of turning energy in the clutch Deployment energy can be implemented with structurally simple measures can.

According to the invention, this object is achieved by a clutch direction, in particular friction clutch for a motor vehicle, in which a clutch state can be produced by the contact pressure of an energy accumulator is comprising a releaser, by means of which optionally one of the Contact force of the energy accumulator at least partially compensating Disengagement force can be generated, the releaser being an energy conversion arrangement voltage for converting the rotational energy of the coupling device into Disengagement energy.

According to the present invention it is further provided that the energy conversion arrangement comprises a generator arrangement for converting Rotational energy in electrical energy as well as a magnetic force generation arrangement for converting output by the generator arrangement electrical energy into the release force.

The present invention avoids the provision of any fluid tight rooms to be locked and generates the required release force electromagnetic interaction. This has the further advantage that the conversion of turning energy into disengagement energy or disengagement force practically no mechanical friction is generated, so that on the one hand Drive system with regard to the power flow running through it is affected as little as possible and secondly the risk of  Wear or damage to any component in operation is minimized.

For example, it can be provided that the generator arrangement is connected to one the first generator part provided with the coupling device and one with the coupling device essentially non-rotatable second Has generator part.

It is advantageous if one of the generator parts is electrically connected to a first interaction part of the magnetic force generating arrangement is connected and if a second interaction part of the magnetic force Generation arrangement is mechanically coupled to the energy accumulator. A particularly simple structure in which the supply of electrical Lines to rotating components is avoided, is achieved if the first interaction part with the coupling device in is essentially not rotatable.

For example, it can be provided that the first interaction part at least one coil electrically connected to the second generator part includes.

The generator arrangement preferably comprises a direct current generator.

According to a second aspect of the present invention is furthermore provided that the energy conversion arrangement is a movement conversion arrangement tion comprises for implementing a rotary movement of the coupling device in a disengaging movement of one acting on the energy accumulator Release member and a coupling arrangement for optional coupling tion of the motion conversion arrangement to a rotating clutch component of the coupling device, and that the coupling arrangement a friction surface arrangement on the clutch component on the one hand and the  Movement conversion arrangement on the other hand, as well as a force generation direction includes for selectively generating a mutual frictional Installation of the friction surface arrangements.

Even with such a configuration it is achieved that no fluid-tight areas to be sealed in the area of the rotating components must be provided. The rotary drive can be engaged friction surfaces that can be brought together can be obtained.

Again, it is possible that the force generating device Magnetic force generating part includes. For example, that the magnetic force generating part comprises at least one coil, which then on the coupling component or the movement conversion arrangement can be provided.

Furthermore, the movement conversion arrangement can be connected to the clutch comm component that can optionally be coupled for rotation and an with the input element is non-rotatable, but displaceable with respect to this Output element include which at least part of the release limb forms.

To the required release actuation of an energy accumulator, which in is generally designed as a diaphragm spring to get before struck that the motion conversion assembly is a gear assembly comprises for converting a rotary movement of the output element into a Displacement movement of the same.

It can be provided, for example, that the gear arrangement is a first thread configuration on the output element and one with the first thread configuration engaging second thread con figuration on one with the coupling device essentially not rotatable component comprises.

The present invention will hereinafter be described with reference to the accompanying Drawings in detail based on preferred embodiments described. It shows:

Fig. 1 is a schematic longitudinal sectional view of a coupling device according to the Invention; and

Fig. 2 is a partial longitudinal sectional view of a modification of the coupling device shown in Fig. 1.

In Fig. 1, a coupling device according to the invention is generally designated 10 . This coupling device 10 comprises a flywheel 12 , on which a pressure plate assembly, designated 14, is attached in a manner known per se in a manner fixed against relative rotation. The pressure plate assembly 14 comprises a housing 16 , in which a pressure plate 18 is arranged, which is movable with respect to the housing 16 in the direction of an axis of rotation A, but is essentially non-rotatable with respect to the housing 16 . Between the pressure plate 18 and the flywheel 12, a clutch disc 20 is clamped with their friction linings 22, wherein the clutch disc 20 in the radially inner region to an output shaft 24, which is a generally transmission input shaft is rotatably coupled.

A force accumulator 28 in the form of a diaphragm spring is held on the clutch housing 16 via a plurality of spacer bolts 26 , which acts on the pressure plate 18 with a radially outer section and is acted upon in a radially inner section 30 in the manner described below for performing disengagement movements.

In order to generate the required for performing Ausrückbewegungen force in the inventive coupling device 10 is a generator assembly is a saw 32 having disposed on the housing 16 rotor 34 and on one of the clutch 10 is not rotatable component, such as a bell housing 36, arranged stator 38 before . For example, the stator 38 may include one or more coils and the rotor 34 may include permanent magnets so that an electrical current is induced by the permanent magnets moving past the coils.

The stator 38 is electrically connected via one or more lines 40 to a unit 42 which is likewise not rotatable with the clutch 10 and which, for example, comprises a coil 46 wound on a core 44 or a plurality of such coils. This unit 42 can also be fixed, for example, to the transmission or the transmission bell 36 . In the engaged state shown in FIG. 1, near the unit 42 is a section 48 which is arranged on the radially inner section 30 of the diaphragm spring 28 and can be brought into magnetic interaction with the unit 42 and which can comprise, for example, a permanent magnet ring. These two assemblies 42 , 48 together with the generator 32 essentially form a release 49 or an energy conversion arrangement of the same. If a current flow is generated in the coil 46 , this leads to the generation of a magnetic field which is amplified by the core 44 . This magnetic field interacts with the magnetic field generated by the permanent magnet ring 48 , so that when the coil 46 is energized, a repulsive force is generated between the unit 42 and the radially inner section 30 of the diaphragm spring 28 and the membrane spring 28 in this section 30 in the representation of FIG. 1 is moved to the left, ie away from the unit 42 and, accordingly, gives up the charging of the pressure plate in the radially outer region 18, or at least reduces. The clutch 10 can thus be brought into its disengaged or partially disengaged state. To achieve this, a switch 50 can be provided in the line system 40, for example. If the clutch is to be brought back into the engaged state, the switch 50 is brought into the open position shown in dashed lines in the figure, so that the current flow through the coil 46 is stopped and the repulsive interaction between the unit 42 and the permanent magnet ring 48 also is ended.

In order not only to obtain completely disengaged and engaged states here, but also to be able to set up intermediate states, the switch 50 can, for example, be activated by a control device (not shown), e.g. B. in accordance with the extent of depression of a clutch pedal or according to the specification by a control device in a clocked operating state in order to reduce the strength of the interaction between the unit 42 and the permanent magnet ring 48 averaged over time. It is also possible to set the current flow through the coil 46 in accordance with the desired disengagement stroke of the membrane spring 28 by a control device (not shown in the figure) arranged in the line system 40 , in order to be able to achieve intermediate states in this way.

The generator 32 is preferably designed such that it is capable of delivering a direct current. Alternatively, however, it is also possible to convert an alternating current generated by the generator 32 into a direct current in a circuit integrated in the line or lines 40 .

It should be noted that it is also possible to change the functions of the rotor and stator as well as the unit 42 and the section 48 , so that the electrically connected assemblies are integrated in the coupling and the non-electrically connected assemblies on stationary units or components are defined.

A modification of the friction clutch according to the invention is shown in FIG. 2. Components which correspond to components described above with regard to structure or function are identified by the same reference number with the addition of an appendix "a".

In the embodiment according to Fig. 2, the rotation of the clutch 10 a, ie, the clutch housing 16 a, by a motion conversion device 60 a in a disengaging movement of the diaphragm spring 28 a reacted. For this purpose, a coupling arrangement 62 a is seen before, through which a disk-like or ring-shaped input element 64 a of the movement conversion arrangement 60 a can optionally be coupled more or less rotatably with the coupling housing 16 a. This coupling arrangement 62a comprises, in the illustrated embodiment, an electromagnetically-acting force-generating means 66 a with the clutch housing 16 a provided for the coil 68 a, which can be supplied via a wiper 70 a with power and for which a portion 69 a of the housing 16 a a core forms. For example, permanent magnets can be provided on the ring element 64 a, which are attracted by the coil 68 a when a magnetic field is generated and thus the ring-like component 64 a with a friction surface or a friction lining 72 a in the friction system on a corresponding friction surface or a friction lining 74 a Housing 16 a brings. The ring-like component 64 a has in its radially inner region an engagement formation 76 a, for example a toothing 76 a, which with a complementary engagement formation 78 a, for example likewise a toothing 78 a, an output component 80 a of the motion conversion arrangement 60 a in such engagement stands that the input component 64 a and the output component 80 a are rotatably connected to each other, but are axially displaceable with respect to each other. The output component 80 a acts on a release bearing 82 a the radially inner portion of the diaphragm spring 30 a. A rotation of the input component 64 a, and thus the output component 80 a in a Axialverschiebebewegung Ausgangskom the component 80 a to implement, a gear arrangement is provided a 84th This comprises a thread formation 88 a on a component 86 a which is not rotatable with the clutch 10 a, for example fixed on the transmission, and a corresponding thread formation 90 a on an inner peripheral surface of the output component 80 a. Is brought about by energizing the coil 68 a, the input component 64 a frictionally engaged with the clutch housing 16 a, the rotational movement generated thereby is a converted to a Axialverschiebebewegung the output component 80 a 84 of the Eingangskom component 64 a and the output component 80 a voltage by the Getriebeanord , which then axially entrains the radially inner portion 30 a of the diaphragm spring 28 a, so that the radially outer region thereof at least partially releases the pressure plate. The component 86 a also has an axial stop 92 a, which ensures that an excessive axial movement of the output component 80 a and thus the radially inner portion 30 a of the diaphragm spring 28 a is prevented.

It is pointed out that in the embodiment shown in FIG. 2, the coil 68 a used to generate the electromagnetic interaction could also be provided on the ring-like input component 64 a.

In order to be able to obtain intermediate states between a fully disengaged and a fully engaged state of the clutch also in the embodiment according to FIG. 2, the electrical current to be supplied to the coil 68 a can be set by a control device (not shown) such that the electromagnetic interaction between the coil 68 a and the input component 64 a, the friction force generated between the friction surfaces 72 a, 74 a allows a certain slip, so that a balance of forces between the driving force generated by the driving of the input component 64 a and the counteracting force of the diaphragm spring 28 a is set.

The present invention provides a coupling device which with simple construction from the rotation of the coupling device itself can take energy and then this energy into an off  back energy or release force to actuate the clutch can implement.

Claims (13)

Is 1. clutch device, in particular friction clutch for a motor vehicle in which a clutch state is produced by the pressing force of a force store (28), comprising a clutch operator (49) through which optionally a, the pressing force of the force accumulator (28) at least partially compensating releasing force generated , wherein the releaser ( 49 ) has an energy conversion arrangement ( 32 , 42 , 48 ) for converting rotational energy of the clutch device into disengagement energy, characterized in that the energy conversion arrangement ( 32 , 42 , 48 ) comprises a generator arrangement ( 32 ) for converting Rotation energy into electrical energy and a magnetic force generating arrangement ( 42 , 48 ) for converting electrical energy output by the generator arrangement ( 32 ) into the disengaging force. 2. Coupling device according to claim 1, characterized in that the generator arrangement ( 32 ) has a on the coupling device ( 10 ) provided first generator part ( 34 ) and with the coupling device ( 10 ) substantially non-rotatable second generator part ( 38 ). 3. Coupling device according to claim 2, characterized in that one ( 38 ) of the generator parts ( 34 , 38 ) is electrically connected to a first interaction part ( 42 ) of the magnetic force generating arrangement ( 42 , 48 ) and that a second interaction part ( 48 ) Magnetic force generation arrangement ( 42 , 48 ) is mechanically coupled to the energy store ( 28 ). 4. Coupling device according to claim 3, characterized in that the first interaction part ( 42 ) with the coupling device ( 10 ) is substantially not rotatable. 5. Coupling device according to one of claims 1 to 4, characterized in that the first interaction part comprises at least one with the second generator part ( 38 ) electrically connected coil ( 46 ). 6. Coupling device according to one of claims 1 to 5, characterized in that the generator arrangement ( 32 ) comprises a direct current generator ( 32 ). 7. Coupling device according to the preamble of claim 1, wherein the energy conversion arrangement comprises a movement conversion arrangement ( 60 a) for converting a rotary movement of the coupling device ( 10 a) into a disengagement movement of a disengaging member ( 80 a) acting on the energy accumulator ( 28 a) and a coupling arrangement ( 62 a) for optional coupling of the movement conversion arrangement ( 60 ) to a rotating coupling component ( 16 a) of the coupling device ( 10 a), characterized in that the coupling arrangement ( 62 a) has a friction surface arrangement ( 72 a, 74 a) on the Coupling component ( 16 a) on the one hand and the movement conversion arrangement ( 60 a) on the other hand and a force generating device ( 68 a) comprises for selectively generating a mutual frictional contact of the friction surface arrangements ( 72 a, 74 a). In that the force generating means (68 a) (68 a) comprises 8. A coupling device according to claim 7, characterized in that a mounting part Magnetkrafterzeu. That the magnetic force generating part (68 a) at least (68 a) comprises 9. A coupling device according to claim 8, characterized in that a coil. 10. Coupling device according to claim 9, characterized in that the at least one coil ( 68 a) on the coupling component ( 16 a) or the movement conversion arrangement ( 60 a) is provided. 11. Coupling device according to one of claims 7 to 10, characterized in that the movement conversion arrangement ( 60 a) with the coupling component ( 16 a) optionally connectable for rotation input element ( 64 a) and with the input element ( 64 a) rotatably, with respect this, however, comprises displaceable output element, which forms at least part of the release member ( 80 a). 12. Coupling device according to claim 11, characterized in that the movement conversion arrangement ( 60 a) comprises a gear arrangement ( 84 a) for converting a rotary movement of the output element ( 80 a) in a displacement movement of the same. 13. Coupling device according to claim 11, characterized in that a gear arrangement ( 86 a) a first thread configuration ( 90 a) on the output element ( 80 a) and with the first thread configuration ( 90 a) engaging second thread configuration ( 88 a ) on a component ( 86 a) which is essentially non-rotatable with the coupling device ( 10 a).