System for operating a clutch

Abstract

Clutch actuation system for a clutch (1), comprising an actuator device, by means of which a drive element (6) can be non-positively connected to an output element (5) which can be rotated relative to the drive element (6), wherein the actuator device is designed and arranged such that kinetic energy of the drive element (6) is used to apply an actuating force for opening and / or closing the clutch (1), characterized in that the actuator device comprises a bearing (18) which is adjustable to represent different transmission ratios between a first conical surface (31) on one or the actuating element (14) and a second conical surface (32) on the drive element (6), wherein the bearing (18) is arranged on a guide and adjustment device (20), and wherein the guide and adjustment device (20) comprises an eccentric guide tube (21) which is coupled to the bearing (18) via a slotted guide.wherein the eccentric guide tube (21) comprises a central through-hole on the inside through which the output element (5) extends, wherein the eccentric guide tube (21) is designed to be eccentric radially on the outside.

Description

The invention relates to a method for actuating a clutch, having an actuator device, with the aid of which a drive element can be connected in a force-fitting manner to an output element, which can be rotated relative to the drive element. The invention further relates to a clutch actuation system for a clutch, having an actuator device, with the aid of which a drive element can be connected in a force-fitting manner to an output element, which can be rotated relative to the drive element.German laid-open specification DE 10 2010 047 801 A1 discloses a hydrostatic actuator having a master cylinder and having a planetary roller transmission which converts a rotary drive into an axial movement and has a sleeve, a transmission spindle and planetary rollers which roll between the latter, and having an electric motor which drives the planetary roller transmission. A system according to the preamble of claim 1 is known from DE 10 2009 015 151 A1. Further prior art is disclosed in DE 2 401 385 A, DE 197 00 935 A1 and WO 2007 / 025 522 A2.It is the object of the invention to simplify and / or improve the actuation of a clutch with an actuator device, with the aid of which a drive element can be connected in a force-fitting manner to an output element, which can be rotated relative to the drive element, in particular with regard to the required actuation energy and / or the production costs of the actuator device.The object is achieved with an actuator device, with the aid of which a drive element can be connected in a force-fitting manner to an output element, which can be rotated relative to the drive element, in that kinetic energy of the drive element is used to generate an actuating force for opening and / or closing the clutch. The drive element comprises, for example, a flywheel which is connected in a rotationally fixed manner to a crankshaft of an internal combustion engine in the drive train of a motor vehicle. A clutch cover is fastened to the flywheel, for example, which is connected to the crankshaft in a rotationally fixed manner via the flywheel. During operation of the drive train, the clutch cover rotates at the same rotational speed as the crankshaft. The speed of the crankshaft is also referred to as engine speed. The use of the kinetic energy of the drive element for actuating the clutch provides, inter alia, the advantage that no additional drive energy or no additional drive is required for actuating the clutch.A preferred exemplary embodiment of the method is characterized in that a rotational speed difference between the drive element and an actuating element is set for a short time in order to generate the actuating force for opening and / or closing the clutch. The actuating element is rotatable relative to the drive element, advantageously with the interposition of a bearing. The rotational speed difference between the drive element and the actuating element is specifically brought about in order to generate the actuating force for opening or closing the clutch.A further preferred exemplary embodiment of the method is characterized in that the rotational speed difference between the drive element and the actuating element is adjusted with the aid of an electromotive drive. This advantageously provides a purely electromechanical clutch actuation system without a hydraulic intermediate section. The electromotive drive is advantageously used only to produce the rotational speed difference between the drive element and the actuating element. The electric motor drive is not directly used or needed to generate the operating force.In a clutch actuation system for a clutch, having an actuator device, with the aid of which a drive element can be connected in a force-fitting manner to an output element, which can be rotated relative to the drive element, in particular according to a method described above, the object indicated above is alternatively or additionally achieved in that the actuator device is designed and arranged in such a way that kinetic energy of the drive element is used for applying an actuation force for opening and / or closing the clutch. By means of the actuator device according to the invention, an existing rotational movement of the drive element can be partially converted in a simple manner into an axially acting actuating force for opening and / or closing the clutch. The energy conversion is advantageously carried out purely mechanically.A preferred exemplary embodiment of the clutch actuation system is characterized in that the actuator device comprises a ramp mechanism which applies an axial actuating force to a pressure plate as a function of a or the rotational speed difference between an or the actuating element and the drive element. The pressure plate can advantageously be displaced in the axial direction to a limited extent relative to a clutch disk. The term axial refers to an axis of rotation of the input member and the output member. Due to the axial displacement of the pressure plate, the clutch disk can be clamped between the pressure plate and the flywheel in order to generate a frictional connection. The generation of the frictional connection is also referred to as closing of the clutch. The ramp mechanism advantageously serves to generate an actuating force in the axial direction with the aid of the rotational speed difference and the rotational speed of the engine. The ramp mechanism advantageously comprises first ramps which are provided on the drive element, in particular the clutch cover, and second ramps which are provided on the pressure plate. The actuating element is advantageously arranged, in the axial direction, between the clutch cover and the pressure plate.The clutch actuation system is characterized in that the actuator device comprises a bearing which is adjustable for the purpose of presenting different transmission ratios between a first conical surface on a or the actuation element and a second conical surface on the drive element. The bearing is advantageously designed as a ball bearing. An outer bearing ring of the bearing is advantageously arranged between the two conical surfaces. With the aid of the conical surfaces and the bearing, a rotational speed difference between the rotational speed of the drive element and the actuating element can be adjusted in order to rotate the drive element, in particular the clutch cover, relative to the ramp mechanism. By rotating the ramp mechanism, the pressure plate is axially displaced in order to open or close the clutch. The adjustment of the transmission ratio with the aid of the bearing takes place advantageously only briefly. Normally, a transmission ratio of 1:1 is set via the bearing in order to maintain a constant torque.The clutch actuation system is further characterized in that the bearing is arranged on a guiding and adjusting device. The guiding and adjusting device is advantageously arranged radially inside the two conical surfaces. In this case, the guiding and adjusting device is advantageously designed and arranged such that the output element, in particular a transmission input shaft, extends through the guiding and adjusting device.The clutch actuation system is characterized in that the guiding and adjusting device comprises an eccentric guide tube which is coupled to the bearing via a link. The eccentric guide tube advantageously comprises a central through hole on the inside, through which the transmission input shaft or the output element extends. Radially on the outside, the eccentric guide tube is advantageously designed eccentrically in order to enable the transmission ratio adjustment with the aid of the bearing.A further preferred exemplary embodiment of the clutch actuation system is characterized in that the guiding and adjusting device is driven by an electric motor via a worm gear. A rotational movement of a motor shaft of the electric motor can be converted into a rotational movement of the eccentric guide tube via the worm gear. The electric motor drive is advantageously only required for adjusting the transmission ratio with the aid of the bearing.The invention further relates to a computer program product having a computer program, which has software means for carrying out the method described above when the computer program is executed on a computer. The computer program product is advantageously assigned to a clutch control unit in a motor vehicle, with which a clutch actuator of an actuator device described above can be actuated, in particular in order to control the bearing described above in an axially guided manner and as a function of the rotational speed. Thereby, the above-described clutch can be easily engaged and disengaged. The clutch can advantageously be actively engaged.The invention further relates to an actuator device, a ramp mechanism, an actuating element, a drive element, a bearing, a guiding and adjusting device, in particular an eccentric guide tube, a link, a worm gear and / or an electric motor for a clutch actuation system described above. The parts mentioned can be purchased separately.Further advantages, features and details of the invention will become apparent from the following description, in which an exemplary embodiment is described in detail with reference to the drawing.In the single enclosed figure, a drive train of a motor vehicle with a clutch is shown in simplified form in longitudinal section.In the single accompanying figure, a drive train of a motor vehicle with a clutch 1 is shown in simplified longitudinal section. The clutch 1 comprises a clutch disk 2 which is connected in a rotationally fixed manner to one end of a transmission input shaft 4. the transmission input shaft 4 represents an output element 5 which is rotatable relative to a drive element 6.The drive element 6 comprises a crankshaft 8 which rotates in the drive train of the motor vehicle at the speed of an internal combustion engine. The internal combustion engine is also referred to as a motor. Accordingly, the rotational speed at which the crankshaft 8 rotates is also referred to as engine speed.A flywheel 9 is connected to the crankshaft 8 in a rotationally fixed manner by means of screw connection elements. A clutch cover 10 is in turn connected to the flywheel 9 in a rotationally fixed manner. The clutch cover 10 constitutes a part of the driving member 6 and rotates at engine speed.The clutch cover 10 constitutes a pressure pot, the bottom of which is formed by the flywheel 9. On the side facing away from flywheel 9, clutch cover 10 has a central through-hole, which is bounded by a conical ring cover 11. Adjacent to the conical ring cover 11 there is arranged a conical disk 12 which is angled by an actuating element 14.The conical disk 12 is arranged at an angle of approximately twenty-five degrees with respect to a rotational axis 13 of the transmission input shaft 4 or of the crankshaft 8. The conical ring cover 11 is arranged at an angle of approximately twenty degrees to the axis of rotation 13. In this case, the conical ring cover 11 extends away from the crankshaft 9, while the conical disk 12 extends toward the crankshaft 8.The conical disk 12 is angled radially on the inside by a substantially circular-disk-like actuating element 14. The actuating element 14 interacts with a ramp mechanism 15 and is arranged in the axial direction between the clutch cover 10 and a pressure plate 16. The ramp mechanism 15 includes ramps mounted on the clutch cover 10. Further ramps of the ramp mechanism 15, which can also be referred to as counter ramps, are attached to the pressure plate 16.The pressure plate 16 is axially displaceable to a limited extent by means of the ramp mechanism 15 in order to open or close the clutch 1. When the clutch 1 is closed, the pressure plate 16 is moved toward the clutch disk 2 in such a way that the clutch disk 2 is clamped between the pressure plate 16 and the flywheel 9 in order to produce a frictional connection. When the pressure plate 16 is moved away from the clutch disk 2, the clutch 1 is opened.The conical disk 12 of the actuating element 14 has a first conical surface 31 radially on the inside. A second conical surface 32 is arranged radially on the inside on the conical ring cover 11 of the clutch cover 10. A bearing 18 is arranged between the two conical surfaces 31, 32. The bearing 18 is designed as a ball bearing with an outer bearing ring which is arranged between the two conical surfaces 31 and 32.The bearing 8 is arranged on a guiding and adjusting device 20 for adjusting a transmission ratio between the actuating element 14 and the clutch cover 10. The guiding and adjusting device 20 comprises an eccentric guide tube 21 with a bearing guide 19. The electric motor drive 24 comprises an electric motor 25. The motor shaft 26 is coupled to the eccentric guide tube 21 via a worm gear 28.According to an essential aspect of the invention, a portion of the kinetic energy, in particular rotational energy, which is provided by the drive motor via the crankshaft 8, is used for actuating the clutch 1. The rotational energy provided by the drive motor acts via the flywheel 9 on the clutch cover 10.The ball bearing 18 is advantageously designed in such a way that it can be moved between the two conical surfaces 31 and 32 starting from the electric motor drive 24 via the worm gear 28 and the guiding and adjusting device 20. The slotted link (not shown) attached to the eccentric guide tube 21 enables the bearing 18 to be axially guided, controlled, moved, in particular displaced. The bearing 18 advantageously transmits the rotational movement of the clutch cover 10 to the ramp mechanism 15, which is radially braced with the bearing 18.As the bearing 18 describes a larger radius of the cone, the rotational speed of the bearing 18 increases, thereby establishing a speed difference between the rotational speed of the clutch cover 10 and the ramp mechanism 15. This rotational speed difference results in the clutch cover 10 rotating radially with respect to the ramp mechanism 15. The rotation of the ramp mechanism 15 moves the pressure plate 16 axially. The axial displacement causes the clutch 1 to open or disconnect.If, on the other hand, the bearing 18 describes a smaller radius on the cone, the rotational speed of the bearing 18 slows down toward the clutch cover 10, so that the clutch 1 closes. A transmission ratio of 1:1 between the two conical surfaces 31, 32 serves to maintain a constant torque.List of reference characters1 Clutch 2 Clutch disk 4 Transmission input shaft 5 Output element 6 Drive element 8 Crankshaft 9 Flywheel 10 Clutch cover 11 Conical ring cover 12 Conical disk 13 Axis of rotation 14 Actuating element 15 Ramp mechanism 16 Pressure plate 18 Bearing 19 Bearing guide 20 Guiding and adjusting device 21 Eccentric guide tube 24 Electromotive drive 25 Electric motor 26 Motor shaft 29 Worm gear 31 Conical surface 32 Conical surface

Claims

Clutch actuation system for a clutch (1), having an actuator device, with the aid of which a drive element (6) can be connected in a force-fitting manner to an output element (5), which can be rotated relative to the drive element (6), wherein the actuator device is designed and arranged such that kinetic energy of the drive element (6) is used for applying an actuating force for opening and / or closing the clutch (1), characterized in that the actuator device comprises a bearing (18), which can be adjusted for the purpose of representing different transmission ratios between a first conical surface (31) on a or the actuating element (14) and a second conical surface (32) on the drive element (6), wherein the bearing (18) is arranged on a guide and adjustment device (20), and wherein the guide and adjustment device (20) comprises an eccentric guide tube (21), which is coupled to the bearing (18) via a link, wherein the eccentric guide tube (21) comprises on the inside a central through hole through which the output element (5) extends, wherein the eccentric guide tube (21) is eccentrically designed radially on the outside.Clutch actuation system according to Claim 1, characterized in that the actuator device comprises a ramp mechanism (15) which applies an axial actuating force to a pressure plate (16) as a function of a or the rotational speed difference between an or the actuating element (14) and the drive element (6).Clutch actuation system according to Claim 1 or 2, characterized in that the guide and adjustment device (20) is driven by an electric motor (25) via a worm gear (28).

Images