DE102007020224A1 - Vehicle comprises a monitoring unit for monitoring the operating state assigned to a clutch arrangement for acquiring an abnormal operating state - Google Patents

Abstract

Vehicle (10) comprises a monitoring unit (60) for monitoring the operating state assigned to a clutch arrangement (20) for acquiring an abnormal operating state. A control unit (12) influences a further power train component in the presence of an abnormal operating state of the clutch arrangement. Preferred Features: The power train component represents the engine (16) or a gearing arrangement (18). The gearing arrangement is formed as an automatic gearshift.

Description

The The invention relates to a motor vehicle according to the preamble of the claim 1.

It It is known that for starting and changing gears in motor vehicles existing coupling device during its operation high Is exposed to stress. In addition to the performance-related conditional Wear a Friction clutch are also all receiving an actuating force and forwarding components of the clutch, whose actuator and also subject to electronic control components aging, their vulnerability and probability of failure with progressive life and increasing Load cycles increases sharply. This is reflected among others in it down that a not insignificant number of vehicle breakdowns in connection with a defect of the coupling device in connection stands. If such a defect during of driving occurs, so it may for example at a Damage to the release button when pressed, d. H. open Clutch come to a sudden engagement. Otherwise, can The friction clutch is not on an operation intention of a driver or a Actuators react and remain inadvertently and undesirably closed. Especially with a sudden engagement process can the driver easily over control lose the vehicle, causing an uncontrolled movement of the Vehicle in connection with a special hazard situation of the driver and uninvolved persons can come.

When a default risk Component may in particular designed as a rolling bearing release bearing the release device be considered, which is the operative connection between a the coupling axis rotating release member, z. B. a diaphragm spring, and a rotationally fixed actuating element, z. B. a clutch fork manufactures. The release bearing, which is mainly used as a radial or angular contact ball bearings accomplished is, in addition to high radial forces in particular at one activity the friction clutch extreme axial forces. It can be in practice For example, in conjunction with insufficient lubrication of the release bearing happen that this is hot and running that in consequence a in the rolling bearing usually made of plastic manufactured ball cage destroyed and the mutual spacing of the rolling elements is canceled. This can in turn lead to a blocking of the rolling bearing and to an undesirable cause mutual axial displacement of the bearing rings, wherein in the worst case Case the cohesion of the bearing rings can no longer be maintained can and with a coupling of the drawn type with the release member operatively connected bearing ring with respect to the other bearing ring axially is disconnected, so that the friction clutch is no longer actuated thereby can. This problem can equally well with a release device from the pressed However, however, because of the in relation to the drawn type reversed direction of force direction, the bearing rings not from each other be separated but can be pushed axially into each other. When doing so exceeded a certain axial offset If so, such a release bearing can fail during operation.

Other Failure causes can For example, be the failure of a coupling member, in particular the breakage of a diaphragm spring, the failure of a clutch lever assembly, eg a release fork, the failure of a clutch hydraulic or pneumatic component, the Failure of a clutch control electronics or other to the coupling device belonging Components.

From Starting from this problem, the invention has the task of to provide a motor vehicle of the generic type, which in the event of an unpredictable defect occurring at the coupling device an uncontrolled movement of the vehicle avoids or these limits.

The Invention solves the problem posed in a generic vehicle with the license plate of patent claim 1 listed Features.

It Accordingly, a motor vehicle is provided with a vehicle control and with a drive train, which is a drive unit, a gear change transmission and a coupling device, wherein the coupling device one in operative connection between the prime mover and the transmission arranged friction clutch and an actuating device. It is inventively provided that of the coupling device for detecting an abnormal operating state an operating condition monitoring device is assigned, where at in the presence of an abnormal operating condition the coupling device, the vehicle control in dependence from a predetermined driving state of the vehicle at least one further powertrain component for the transition of the vehicle in one safe state influenced.

It is thus initially the test, whether the coupling device operates normally. If this is not the case, the presence of a predetermined driving condition is detected by the vehicle controller. Only when both of the above conditions are met, the further drive strand component influenced.

Under the term actuator should all for the clutch operation necessary assemblies are understood, d. H. especially mechanical, electromechanical, electronic, hydraulic and pneumatic functional elements.

In a particularly advantageous embodiment of the invention the other powertrain component the prime mover or a preferably designed as an automated transmission gear change transmission represents.

According to one Another advantageous embodiment of the invention is the operating state monitoring device for determining an operating state of at least two in one Signal flow or power transmission path for operation the clutch arranged components formed. You can do this different positions within the signal flow or power transmission path Sensors or switches may be arranged, their signal or their Position for a assumed Be operating state of the coupling device are characteristic. In normal operation, the operating states correlate at the different positions, that is z. B. that when actuated Clutch pedal a hydraulic master cylinder a retracted Position and a slave cylinder assumes an extended position, that the release bearing assumes a predetermined axial position to the clutch and also a coupling member, z. B. a diaphragm spring while a predetermined Location has.

From the operation state detection device becomes an operation state detected as abnormal if a given correlation of the operating conditions of the monitored Components is lifted. The abnormal operating state can thereby be caused by a defect or failure of a component the coupling or by defect or failure of a component of Actuating device.

From the driving conditions occurring in practice is with respect to a Failure of the coupling device in particular that of importance, in which the vehicle is in gear and when the brake device is unactuated at standstill. Such a situation occurs, for example at a traffic light stop in the inner city Area or in stop-and-go traffic in a congestion situation on motorways on. In such a situation, a trained according to the invention Motor vehicle particularly useful because in case of failure of the coupling device virtually no safety distance with an uncontrolled vehicle movement exists to other passers-by or vehicles and thus to the driver except one if necessary knee-jerk actuation The braking device barely room for maneuver for an adequate response remains. The for determining the above Fahrzustan the required Sensors, such as crankshaft, camshaft sensor; Wheel speed sensor, transmission speed and transmission gear sensor, service brake or parking brake switch are common already provided on modern vehicles, so that the invention realized solely by simple and known to the expert logic circuit can be.

Around to transfer the vehicle to a safe condition is provided that the prime mover is in operation and in the transmission a gear is engaged, suggested that the prime mover is turned off and / or that the transmission is transferred to a neutral position. As already mentioned, are the for detecting the operating conditions of prime mover and Gear sensors required usually already on vehicles educated. The shutdown of the prime mover can fuel interrupted and possibly the ignition device be deactivated.

The invention is explained below by way of example. The figure shows schematically a motor vehicle 10 with a vehicle control 12 and with a powertrain 14 , which is a prime mover 16 in the form of an internal combustion engine, a manual change gearbox 18 and a pedestrian coupling device 20 includes. The here in simplified form diagrammatically illustrated coupling device 20 has a designed in solid construction friction clutch 22 on, the input side for transmitting torque with the output shaft 17 of the internal combustion engine 16 and output side with the input shaft 15 a gear change transmission 18 connected is. The operation of the friction clutch 22 takes place by means of egg ner actuator 24 that has a release device 26 with one on a wall of the transmission 18 fixed guide tube 26 and an axially displaceable thereon and as a carrier for a release bearing 28 acting sliding sleeve 30 includes. The release bearing 28 is to transmit a force for actuating the friction clutch 22 with its inner bearing ring 32 with a release spring designed as a diaphragm spring 34 the friction clutch 22 in active connection. The outer bearing ring 36 the release bearing 28 is non-rotatable on the sliding sleeve 30 arranged.

The actuating device 24 further comprises a hydraulic master cylinder 38 and a slave cylinder 40 , which by means of a filled with a fluid pressure line 42 are connected and form a common pressure chamber. The master cylinder 38 can by a clutch pedal 44 actuated Be, being a piston 46 the slave cylinder 40 shifts and in consequence a clutch fork 48 pivoted and being further on the sliding sleeve 30 , the rolling bearing 28 and about the disengagement organ 34 a printing plate 50 is axially displaced, thereby rotationally fixed on the transmission input shaft 15 arranged clutch disc 52 The enabling of.

At the coupling device 20 is a switching element 54 for detecting a pedal position of the clutch pedal 44 and a pressure sensor 56 arranged to detect a pressure prevailing in the pressure chamber fluid pressure, the signals from an associated evaluation 58 can be evaluated. In normal operation, the signals of the switching element 54 and the pressure sensor 56 correlated in such a way that when the clutch pedal is pressed 44 the fluid pressure increases and assumes a predetermined amount. Upon occurrence of an abnormal operating condition due to a defective component of the coupling device, for. B. Disconnecting the release bearing 28 , the correlation of the preceding signals is no longer present. If in such a state, the switching element 54 a kicked clutch pedal 44 however, the fluid pressure will not rise to the predetermined extent and the pressure sensor will 56 produce a signal that is correspondingly smaller than the normal state. By the evaluation means 58 Thus, the presence of an abnormal operating state detected and to the higher-level vehicle control 12 be reported. The switching element 54 , the pressure sensor 56 and the evaluation means 58 together form an operating state monitoring device 60 for detecting an abnormal operating state of the clutch device 20 ,

The vehicle control 12 , to which subassemblies, such as a motor control or the control unit of an antilock braking system are to be assigned, are usually already connected to a large number of sensors. In the present example, in the light of the invention, in particular at least one wheel sensor 62 , a transmission sensor 64 and a sensor 66 a braking device acting on the vehicle wheels 68 of further importance. Based on the of these sensors 62 . 64 . 66 supplied signals is the vehicle control 12 able to determine if the vehicle is 10 currently moved, whether a gear is engaged and whether the braking device is activated. If through the vehicle control 12 it is determined that the vehicle 10 when the gear is engaged and when the braking device is unactuated, it is at a standstill and when the operating state detecting device simultaneously has an abnormal operating state of the clutch device 20 has recognized, so will the vehicle 10 transferred to a safe state, the vehicle control 12 the prime mover 16 shuts down. That way, the vehicle can 10 automatically with a defect of the coupling device 20 be turned off in a controlled manner.

Claims (7)

Motor vehicle ( 10 ) with a vehicle control ( 12 ) and with a drive train ( 14 ), which a drive machine ( 16 ), a gear change transmission ( 18 ) and a coupling device ( 20 ), wherein the coupling device ( 20 ) in operative connection between the prime mover ( 16 ) and the gear change transmission ( 18 ) arranged friction clutch ( 22 ) and an actuating device ( 24 ), characterized in that the coupling device ( 20 ) for detecting an abnormal operating condition, an operating state monitoring device ( 60 ) is assigned, wherein in the presence of an abnormal operating state of the coupling device ( 20 ) the vehicle control ( 12 ) in dependence on a predetermined driving state of the vehicle ( 10 ) at least one further drive train component for the transition of the vehicle ( 10 ) into a safe state. Motor vehicle according to claim 1, characterized in that the drive train component the drive machine ( 16 ) or the gear change transmission ( 18 ). Motor vehicle according to claim 1 or 2, characterized in that the operating state monitoring device ( 60 ) for determining an operating state of at least two in a signal flow or power transmission path for actuating the friction clutch ( 22 ) arranged components ( 42 . 44 ) is trained. Motor vehicle according to one of the preceding claims, characterized in that an abnormal operating state is present when a predetermined correlation of the operating states of the monitored components ( 42 . 44 ) is canceled. Motor vehicle according to one of the preceding claims, wherein the vehicle has a braking device ( 68 ), characterized in that the predetermined driving state of the vehicle ( 10 ) is defined by a stoppage of the vehicle ( 10 ) with engaged gear and unconfirmed braking device ( 68 ). Motor vehicle according to one of the preceding claims, characterized in that the drive machine ( 16 ) is turned off. Motor vehicle according to one of the preceding claims, wherein the gear change transmission ( 18 ) is designed as an automated manual transmission, characterized in that the Gangwech selector ( 18 ) is transferred to a neutral position.