Method of and apparatus for detecting friction heat of a clutch and regulating the clutch

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces slidable relative to each other, which is installed in a power train between a prime mover and a variable-speed transmission having first, second and additional forward speeds and a reverse speed, in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and at least one of (a) the extent of slip of the friction surfaces relative to each other and (b) the speed of the transmission, said control unit including means for ascertaining on the basis of signals denoting the speed of the transmission and the condition of the vehicle whether the transmission is set in an additional forward speed for starting of the vehicle and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system due to starting of the vehicle at an additional forward speed of the transmission and initiating at least one of (a) correcting and (b) protective measures when the temperature of at least a portion of said system exceeds a predetermined threshold value.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input of said friction surfaces and for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of at least one predetermined portion of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said initiating step including effecting an adjustment of said device for selection of a torque which varies as a function of time and entails a vibration of the power train.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said device being adjustable by said control unit to modulate the torque which is transmissible by said system so that the modulated torque fluctuates as a function of time.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system and varies within a range including torque above and below a median value;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time (a) a friction energy input at said friction surfaces and (b) for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, the torques which are selected by said device in response to adjustment by said control unit being arranged to fluctuate as a function of time in accordance with one of a plurality of patterns including periodical, aperiodical and statistical fluctuations.

Apparatus for regulating the operation of a torque transmitting system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and for initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said measures including effecting fluctuations of torque of a nature such that a ride in the vehicle is uncomfortable to the occupant or occupants of the vehicle.

Apparatus for regulating the operation of a torque transmitting system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system, and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being a function of signals denoting at least the extent of slip at least in said system and of signals denoting the magnitude of transmissible torque.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said means for ascertaining being operative to generate said output signals in advance and being responsive to at least one of input signals indicating a critical condition of the vehicle including starting of the vehicle at a speed of said variable speed assembly higher than a second forward speed, bringing the vehicle to a halt on a sloping road surface while said system is at least partially engaged and without the application of one or more vehicle brakes, starting or driving the vehicle along a sloping road surface while the system is set for operation with slip, and an attempt to start the vehicle while the wheels of the vehicle are blocked against rotation.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system, and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input of said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said means for ascertaining being responsive to at least one of a plurality of input signals indicating a critical condition of the vehicle including at least one of a friction energy input exceeding a predetermined value and pronounced wear upon said system, said plurality of input signals including signals denoting a selected speed of said assembly, the position of a first brake, the position of a second brake, the extent (if any) of inclination of the vehicle on a road surface, the RPM of the vehicle wheels, the RPM of the prime mover, the input RPM of the assembly, the position of an actuator in said system, the position of a throttle valve in the prime mover, the position of a gas pedal in the vehicle, the torque of said prime mover and the magnitude of transmissible torque, said control unit further comprising means for comparing said at least one signal of said plurality of signals with data in at least one memory of said control unit.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to effect constant, periodical, aperiodical or statistical fluctuations of transmitted torque.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit a torque which increases monotonously as a function of time up to a predetermined threshold value and thereupon remains at least close to said predetermined threshold value.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit a fluctuating torque having an amplitude which varies in accordance with a predetermined pattern up to a fixed or variable threshold value.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit torque which fluctuates in accordance with at least one of a plurality of patterns including linearly, exponentially, stepwise, in sawtooth fashion, and in accordance with a trigonometric function including sine and cosine.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit a torque of a magnitude which varies with successive length-modulated time intervals.

Apparatus for regulating the operation of a torque transmitting system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit a torque of a magnitude which varies with successive time intervals of varying duration.

Apparatus for regulating the operation of a torque transmitting system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit a torque which varies as a function of time without adversely affecting the acceleration and motion of the vehicle.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said output signals being utilized to effect an adjustment of said device so as to transmit a torque which varies as a function of time without affecting at least one of the condition and the operability of the vehicle as well as to denote at least one of (i) increased thermal stressing of and (ii) increasing wear upon said torque transmission system.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said control unit further comprising means for predetermining a desired condition of the vehicle on the basis of at least one of a set of characteristic curves and a characteristic field, and for comparing the actual condition of the vehicle with a predetermined desired condition for the determination of a critical condition of the vehicle on the basis of characteristic curves, said means for initiating at least one of corrective and protective measures including means for generating signals denoting a condition other than said desired condition of the vehicle.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value, said signals denoting the magnitude of transmitted torque including at least one of a plurality of signals denoting the RPM of the prime mover, the position of a load lever, the position of a throttle valve and the fuel injection time, said control unit having means for carrying out at least one of operations including (i) processing said at least one of said plurality of signals for the purpose of ascertaining the magnitude of transmitted torque and (ii) ascertaining the magnitude of transmitted torque on the basis of data in at least one characteristic field in at least one memory of said control unit.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said signal supplying components including at least one sensor arranged to generate signals denoting the selected speed of said assembly and said at least one sensor including a member arranged to monitor the position of at least one movable part of said assembly, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value.

Apparatus for regulating the operation of a torque transmission system having heat generating friction surfaces which are slidable relative to each other, which is installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said system;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, the condition of the vehicle being indicated by at least one of signals supplied by at least one of (i) a sensor and (ii) at least one electronic circuit, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating at least one temperature of said system, for comparing said at least one calculated temperature with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said system and initiating at least one of corrective and protective measures when the at least one calculated temperature exceeds the at least one threshold value.

A method of regulating the operation of a torque transmission system having heat generating friction surfaces, with a regulating device which is operable by a control unit, comprising the steps of transmitting to the control unit signals denoting at least the magnitude of torque being transmitted by the system, the extent of slip of friction surfaces relative to each other, the condition of the system and the selected speed of a variable-speed assembly receiving torque from the system;

• utilizing at least one of said signals to influence the input of energy by the control unit into the friction surfaces of the system;
• calculating the temperature of at least a portion of the system as a function of time;
• comparing the calculated temperature with a threshold value;
• and utilizing the control unit to regulate the operation of the system under at least one of the circumstances including (a) detection of a calculated temperature which exceeds the threshold value and (b) starting of a prime mover for the system at a speed of the variable-speed assembly above a predetermined maximum starting speed, said utilizing step including generating at least one signal for at least one of (a) indication of excessive thermal stressing and (b) initiation of a corrective undertaking, and selecting for the torque transmission system a mode of operation which varies as at least one of (a) a periodical and (b) an aperiodical function of time to result in fluctuations of transmitted torque.

A method of regulating the operation of a torque transmission system having heat generating friction surfaces, with a regulating device which is operable by a control unit, comprising the steps of transmitting to the control unit signals denoting at least the magnitude of torque being transmitted by the system, the extent of slip of friction surfaces relative to each other, the condition of the system and the selected speed of a variable-speed assembly receiving torque from the system;

• utilizing at least one of said signals to influence the input of energy by the control unit into the friction surfaces of the system;
• calculating the temperature of at least a portion of the system as a function of time;
• comparing the calculated temperature with a threshold value;
• and utilizing the control unit to regulate the operation of the system under at least one of the circumstances including (a) detection of a calculated temperature which exceeds the threshold value and (b) starting of a prime mover for the system at a speed of the variable-speed assembly above a predetermined maximum starting speed, said utilizing step including generating at least one signal denoting at least one of excessive energy input, excessive monitored temperature, excessive thermal stressing of at least a portion of the torque transmission system, initiation of a corrective undertaking, and excessive wear at least upon the torque transmission system.

Apparatus for regulating the operation of s torque transmission system including a friction clutch having a rotary flywheel, a rotary pressure plate and a rotary clutch disc between said flywheel and said pressure plate, said pressure plate including a plurality of masses in heat exchanging relationship with each other, said flywheel and said pressure plate and said clutch disc having heat generating friction surfaces which are slidable relative to each other and said friction clutch being installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmitted by said friction clutch;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating the temperature of said pressure plate, for comparing the calculated temperature of said pressure plate with at least one threshold value, and for carrying out at least one of a plurality of undertakings incuding generating output signals denoting excessive thermal stressing of said friction clutch and initiating at least one of corrective and protective measures when the calculated temperature of said pressure plate exceeds the at least one threshold value, the input of said friction energy taking place at said friction surfaces in response to rotation of said flywheel and said pressure plate relative to said clutch disc and said friction energy being divided into a plurality of branches including a first branch entailing a heating of said flywheel and at least one second branch entailing a heating of said pressure plate.

Apparatus for regulating the operation of a torque transmission system including a friction clutch having a rotary flywheel, a rotary pressure plate and a rotary clutch disc between said flywheel and said pressure plate, said pressure plate including a plurality of masses and fixed or temperature-dependent heat transmitting connecting means between said masses, said flywheel and said pressure plate and said clutch disc having heat generating friction surfaces which are slidable relative to each other and said friction clutch being installed in a power train between a prime mover and a variable speed assembly in a motor vehicle, comprising an adjustable device operable to select the torque which is transmittable by said friction clutch;

• and means for adjusting said device including a control unit having input means connected with at least one of a plurality of signal supplying components for supplying signals denoting at least one of several variable parameters indicating the condition of the vehicle, the magnitude of transmitted torque and the extent of slip of the friction surfaces relative to each other, said control unit including means for ascertaining on the basis of said signals and as a function of time a friction energy input at said friction surfaces and means for calculating the temperature of said pressure plate, for comparing the calculated temperature of said pressure plate with at least one threshold value, and for carrying out at least one of a plurality of undertakings including generating output signals denoting excessive thermal stressing of said friction clutch and initiating at least one of corrective and protective measures when the calculated temperature of said pressure plate exceeds the at least one threshold value, the input of said friction energy taking place at said friction surfaces in response to rotation of said flywheel and said pressure plate relative to said clutch disc and said friction energy being divided into a plurality of branches including a first branch entailing a heating of said flywheel and at least one second branch entailing a heating of said pressure plate.