Abstract: There are disclosed a method of and an apparatus for automated actuation of a friction clutch or another torque transmitting system in the power train of a motor vehicle. An actuator for the torque transmitting system can be rendered operative by the ignition key and/or as a result of one or more activities of the operator of the motor vehicle prior or subsequent to insertion of the ignition key. The activity or activities can include the engagement of a brake, the shifting of a transmission lever, stepping on the gas pedal and/or others.

Abstract: The present invention relates to a semi-automatic gearbox system, characterized by the fact that it includes control means suitable for controlling an automatic or semi-automatic operating mode for changing gear ratios in the gearbox. When actuated by the driver, the gear lever transmits the driver's request to the computer, via the sensors. After analyzing the legitimacy of the driver's request, the module proceeds to change the gear as requested. The module controls the electrically driven valves for controlling the clutch, and gear selection and engagement, and establishes dialog with the engine control computer for appropriately managing the engine torque and the engine speed during the gear change. The commands are confirmed by the position sensors on the actuators, and by the sensors for sensing the engine speed, and the inlet speed and the outlet speed of the gearbox. The absolute gear ratio engaged in the gearbox is displayed on the display.

Abstract: A gear control for reduces the thermal stress on switching components (2, 3, 4, 5, 6) of a reversing gear (1) for machines having an input shaft (8) and an output shaft (15) and at least one directional switch for forward motion (2) and one for reverse motion (3) and a downstream load-switchable switching set (4) with several switching components (5, 6) allocated to a gear. Here the switching components (2, 3, 5, 6) can be electrically and/or hydraulically controlled by a regulating and control device (12) in such a way that, during a switching operation, in addition to one of the directional switching components (2, 3) corresponding to the switching operation, at least one other switching components (5, 6) of the downstream switching set (4) lying in the power flow and fully engaged at the start of a reversal is set to a slip state under frictional load. The frictional load is thus distributed between the directional switching components (2, 3) and the other slipping switching components (5, 6).

Abstract: A transmission assembly and method for controlling a torque converter of a transmission assembly in which an electronic controller monitors the load on the vehicle power train in addition to a number of other vehicle dynamics, including the currently engaged gear ratio and the temperature of the transmission fluid. The electronic controller is operable for causing the activation of the converter clutch in response to a number of predetermined operating conditions, one of which includes the operation of the vehicle when the fluid in the torque converter exceeds a predetermined temperature and the vehicle power train is operated under a heavy load for a period of time which exceeds a predetermined time interval. Engagement of the converter clutch during such times inhibits relative rotation between the torque converter turbine and impeller, improving fuel economy and preventing the torque converter from generating a substantial amount of heat.

Abstract: A system for controlling gear (gear ratio) shifting in an automatic transmission mounted on a vehicle, including a shift control means for generating a shift command to upshift from one gear (gear ratio) currently established to a next gear (gear ratio) by determining a command to the solenoid valves to discharge the pressurized oil from the frictional engaging elements that establish the current gear (gear ratio) so as to slip-control the frictional engaging elements, and to charge the pressurized oil to the frictional engaging elements that establish the next gear (gear ratio) to be shifted to.

Abstract: A method of monitoring a torque transmission system with a manually switchable gearbox in the power train of a motor vehicle involves the utilization of at least one sensor unit at the input side of the torque transmission system to ascertain relevant positions of the shift lever of the gearbox and the driving torque of the engine of the motor vehicle. The thus obtained shift lever signals are memorized, together with comparison signals which are obtained as a result of filtering of the shift lever signals, and various characteristics of such signals are recognized and identified to indicate the intention of the operator of the vehicle regarding the switching of the gearbox. The thus obtained switching intention signals are transmitted to a controlled clutch operating system.

Abstract: A system and method for decreasing the time required to complete a ratio change in an electronically enhanced powertrain system is provided. The powertrain system includes a number of devices for providing a retarding torque to engine rotation to increase the decay rate of the engine speed during an upshift. These devices include an engine brake and an input shaft brake. A retarding torque is also provided by increasing engine accessory load by controlling various engine accessories such as a cooling fan, an air compressor, a hydraulic pump, an air conditioning compressor, and an alternator.

Abstract: In a method of controlling an automatic clutch disposed between a motor, especially an internal combustion engine, and the drive train of a vehicle which includes an arbitrarily operable transmission, the clutch is engaged in dependence on the torque generated by the motor in such a manner that the torque which can be transmitted by the clutch is only slightly above the motor-generated torque and, immediately after a transmission ratio change, the clutch is first fully engaged for the transmission of maximum torque if the motor torque exceeds a certain threshold value.

Abstract: A control system for a vehicle transmission prevents a vehicle from rolling backward on a slope, and includes a slope sensor for sensing the degree of a slope, a throttle position sensor for sensing position of a throttle valve, an engine RPM sensor for detecting RPM of the engine, a gear input speed sensor for sensing rotational speed of a transmission gear, a gear position sensor for sensing position of the transmission gear, a shift lever sensor for sensing operation of a shift lever, a CPU for reading signals from the sensors and outputting a control signal for keeping the clutch in partial engagement before starting an engine, an electric hydraulic pressure cylinder, and a clutch release cylinder mechanically joined to the electric hydraulic pressure cylinder for joining the clutch.

Abstract: A hydraulic control system for an automatic transmission is disclosed which includes a feedback hydraulic control circuit and a hydraulic correcting circuit. The feedback hydraulic control circuit controls the hydraulic pressure supplied to frictional elements of the automatic transmission under feedback control during a shift operation for adjusting the speed of an input shaft or a rate of change in speed of the input shaft of the automatic transmission to agree with a target speed or a target rate. The hydraulic correcting circuit corrects an output of the feedback hydraulic control circuit so as to suppress vibrations of torque transmitted through a drive train of the automatic transmission caused by control of the hydraulic pressure carried out by the feedback hydraulic control circuit within a range of a resonance frequency of the drive train of the automatic transmission.

Abstract: In a control for an automatic clutch disposed between the engine and the drive train of a vehicle for controlling the vehicle movement at start or during transitional phases, the clutch is controlled in such a way that, with a predetermined low engine speed, movement of the vehicle at a predetermined creeping speed is obtained.

Abstract: A method of monitoring a torque transmission system with a manually switchable gearbox in the power train of a motor vehicle involves the utilization of at least one sensor unit at the input side of the torque transmission system to ascertain relevant positions of the shift lever of the gearbox and the driving torque of the engine of the motor vehicle. The thus obtained shift lever signals are memorized, together with comparison signals which are obtained as a result of filtering of the shift lever signals, and various characteristics of such signals are recognized and identified to indicate the intention of the operator of the vehicle regarding the switching of the gearbox. The thus obtained switching intention signals are transmitted to a controlled clutch operating system.

Abstract: A system and method for decreasing the time required to complete a ratio change in an electronically enhanced powertrain system is provided. The powertrain system includes a number of devices for providing a retarding torque to engine rotation to increase the decay rate of the engine speed during an upshift. These devices include an engine brake and an input shaft brake. A retarding torque is also provided by increasing engine accessory load by controlling various engine accessories such as a cooling fan, an air compressor, a hydraulic pump, an air conditioning compressor, and an alternator.

Abstract: A control is provided for controlling reengagement of a master clutch (16) in a vehicular automated mechanical transmission system. A nominal reengagement rate (CLU.sub.-- RATE) is determined as a function of engine lag (K.sub.1), throttle position (THL), engine acceleration/deceleration (dES/dt) and/or input shaft acceleration/deceleration (dIS/dr). To provide smoother shifting during braking (BRK=1, THL=0) and/or coasting (THL<30%) downshifts, the clutch is reengaged at a rate slower than the nominal reengagement rate.

Abstract: A clutch slip control device includes: a slip revolution speed detecting circuit for detecting an actual slip revolution speed of a clutch; a memory unit for storing constants set to satisfy response and stability of a feedback control system of the slip conditions, the constants being determined by a high-order function approximating variation in input-output frequency characteristics of a plant input for actuating the clutch and the actual slip revolution speed; a first calculation circuit for calculating a first parameter using the constants stored in the memory unit, the first parameter discretely reflecting past data of the plant input, which are obtained in a current feedback control cycle through in a cycle executed a plurality of times before; a second calculation circuit for calculating a second parameter using the constants stored in the memory unit, the second parameter discretely reflecting past data of a deviation of the actual slip revolution speed from a target slip revolution speed, which are

Abstract: A clutch control system for the automatic control of a motor vehicle clutch which connects an engine with a gearbox under the control of a driver-operated gear ratio selector lever. The control system includes an electronic control unit which controls initial clutch take-up on starting of the vehicle, clutch re-engagment following each ratio change, clutch disengagment on movement of the gear selector lever to change the operative ratio of the gearbox, and clutch disengagment on the coming to rest, etc. of the vehicle. The control system also incorporates an automatic calibration routine which is invoked on the inital keying-on of the system, said routine comprising a predetermined sequence of events in which the system responds to actions of the operator and at predetermined that the system is ready to proceed to the next stage of the calibration.

Abstract: A control system and method for a vehicular semi-automatic mechanical transmission system (10) having a clutch operator (30) and an overriding manual clutch control (3) for controlling engagement and disengagement of the master clutch (14) is provided. The control is effective to sense manual clutch disengagement during a downshift and to cease further attempts to cause synchronization by engine fuel manipulation (ES=IS=OS * GR.sub.T) until a change in conditions is sensed.

Abstract: A control method/system for controlling engagement of a target gear ratio (GR.sub.T)in a vehicular automated mechanical transmission system (10) is provided. The control causes engine speed (ES) to be alternately greater than and then less than synchronous engine speed (ES=IS=OS*GR.sub.T) to cause torque reversals across the engaging positive jaw clutch associated with the target gear ratio to minimize or prevent partial engagement caused by torque lock conditions.

Abstract: The clutch actuation system provides for control of the clutch of a manual transmission in a motor vehicle. By use of hydraulics, a vacuum booster and a gradual pressure relief valve a smooth easy control of the manual transmission is accomplished. The vacuum booster provides an assist to the hydraulic system when the clutch must be disengaged or engaged. The power assist facilitates rapid engagement of the clutch and gears. The gradual pressure relief valve provides for a smooth transition in the hydraulic system to engage and disengage the clutch. The rapid smooth assist is aided by the vacuum system of the motor vehicle. For certain motor vehicles the engine oil system is also used to assist.

Abstract: A clutch control system for a motor vehicle having an engine (10), a gearbox (12) having a plurality of gear ratios, and a clutch (14) providing a drive connection between the engine and the gearbox. The control system includes a clutch actuation means (22) for controlling the state of engagement of the clutch and a control unit (36) which receives signals from a plurality of vehicle operating parameter sensors including a gear sensor (32) which indicates that a gear ratio is engaged in the gearbox. The control unit (36) processes these signals to produce a command signal for operation of the clutch actuating means. The control unit (36) ensures that if on powering-up of the control unit (36) the control unit receives a signal from the gear sensor (32) indicating that a gear ratio is engaged in the gearbox (12), the control unit inhibits disengagement of the clutch (14) by the clutch actuation means (22).

Abstract: An electronic clutch management system for motor vehicles with engines having butterfly valves. An actuator under the control of a micro-controller activates a clutch between the engine and a transmission as a function of an ECM sensor which senses the position of the butterfly valve. If the micro-controller breaks down or is disturbed in its function, the micro-controller control is switched off, and control of the actuator element is switched over from the micro-controller to a comparator which is driven directly by the ECM sensor and controls the actuator element to activate the clutch, i.e., into its disengaged or engaged position, in a sense opposite to the position of the butterfly valve.

Abstract: A system and method for controlling the clutches in a vehicle powershift transmission. The control system includes a microprocessor which periodically executes an algorithm and which has a memory in which is stored a sequential set of time reference values and a sequential set of pressure values. The control system applies to each oncoming element a fill pressure pulse for fill periods which are unique for each element. The control system determines shift time values, subsequent to filling of the control elements, as a function of the fill period. The control system applies pressure signals to the control elements at times represented by the shift time values which are unique for each element. The control system determines, subsequent to a realignment time, realignment shift time values which are the same for all of the control elements.

Abstract: A control system/method for controlling the engagement and disengagement of a friction master clutch (16) in an automated mechanical transmission system (10) is provided. The control system/method is effective to minimize shift transient times and to minimize or eliminate the occurrence of cab lurch events.

Abstract: An automatic clutch controller for a vehicle that reduces the oscillatory response to clutch engagement. The automatic clutch controller receives inputs from an engine speed sensor and a transmission input speed sensor and develops a clutch actuation signal controlling a clutch actuator from disengaged to fully engaged. The clutch engagement signal at least partially engages the friction clutch in a manner to cause the measured transmission input speed to asymptotically approach engine speed employing an approximate inverse model of this oscillatory response. The automatic clutch controller preferably includes a PID function and a differential engine speed function, which together adaptively adjust clutch engagement corresponding to vehicle loading.

Abstract: A vehicle clutch engagement position is disclosed wherein the clutch is moved, under computer control, at a constant rate, from a disengaged position toward a fully engaged position while the transmission is in neutral gear, and the position of the clutch is detected at first and second times (T1 and T2). Time T1 corresponds to the time when the detected speed of the transmission input shaft is just above the dropout speed of the input shaft speed sensor. Time T2 corresponds to the time when the detected speed of the input shaft is close to engine speed. The position of the clutch corresponding to the incipient torque point is extrapolated by subtracting an offset amount from the position detected at time T1. The offset is equal to the change in position from T1 to T2 multiplied by the square root of the ratio of the input shaft speeds at T1 and T2.

Abstract: A master clutch control system/method for controlling engagement and disengagement of a vehicular master clutch, preferably a multiple disc wet clutch (14) is provided. Below a reference vehicle speed (OS<REF.sub.OS) and/or a reference engine speed (ES<REF.sub.ES), the clutch is automatically controlled as a function of throttle displacement (THL) while above the reference vehicle speed (OS>REF.sub.OS) and/or reference engine speed (ES>REF.sub.ES) the clutch is controlled as a function of the position of a manual engage/disengage switch (50) biased to the engage selection position thereof.

Abstract: A control for enabling a clutch to be automatically engaged with a power source. An apparatus for automatically controlling the position of a clutch between a power source and a drive train characterized by a control which regulates pressure to a clutch engaging member according to performance criteria of the power source.