Abstract: A line pressure control system for an automatic transmission wherein a shift range is determined by selectively engaging friction elements by means of a line pressure controlled according to an input torque of said automatic transmission. In the present invention, an engine output torque at the front stage of the automatic transmission is estimated from the operating condition. The input torque of the automatic transmission is calculated from the estimated engine output torque and the operation state of a torque converter. The calculated input torque of the automatic transmission is decreased during a predetermined time corresponding to an estimation response delay of the engine output torque after the engine is made in a no-load state, so as to properly control the line pressure.

Abstract: Methods and systems for detecting the linear movement of a shaft utilizing at least two geartooth sensors and two gears, one helical gear and one a normal spur gear are disclosed. As the shaft and gears translate in a linear direction, they are also rotating. Due to the fact one gear is a helical gear and the other is not, as the shaft translates mechanically, there will be a change in the phase between the output of a first geartooth sensor with respect to the second geartooth sensor. This change in phase is converted into linear travel using a simple calculation to detect the linear translation of the shaft.

Abstract: A method for protecting a variator in a continuously variable belt-type transmission of a motor vehicle, simultaneously with a calculation based on an engine signal containing the magnitude of the engine torque and subsequent conversion of a contact-pressure theoretical value, providing the added safety on the variator, that the contact pressure on the variator is measured by a pressure sensor and the maximum transmissible transmission input torque is calculated with reference to this value. The maximum transmissible transmission input torque is then compared with the engine torque to the transmission and in case the maximum transmissible transmission input torque is less than the engine torque, an engine interruption is effected.

Abstract: The comfort level of a gear shift in a motor vehicle with an automated gear-shifting transmission is determined by shift parameters which are dependent on driving parameters and on a shift program mode that is either driver-selected or automatically determined. The shift program mode is identified through a characteristic parameter which can vary in a range of parameter values corresponding to a range of shift program modes.

Abstract: A starting shift control system for a continuously variable transmission is provided which includes a control unit having a high start judgment device for judging whether or not a high start in a high speed side gear ratio is caused on the basis of a comparison between the generated number of the input rotation pulses and the generated number of the output rotation pulses from the time a first vehicle starting operation is performed after start of a prime mover, and a high start control device for restricting downshifting from the high speed side gear ratio to a target gear ratio when a start of the vehicle is judged to be the high start. A starting shift control method is also provided.

Abstract: A steer-by-wire gear shifter comprises: a holder; a rotary shaft rotatably held by the holder; a shift lever whose bottom is fixed on the rotary shaft; a shift knob attached to a top of the shift lever; detecting means for detecting an operational condition of the shift knob; an actuator which applies an external force for force feedback to the shift knob through the rotary shaft and the shift lever; a control section which receives a detection signal a from the detecting means, a transmission signal d from a transmission controller and an engine revolution speed signal e from an engine controller, generates and outputs a control signal b for the actuator and a gear shift signal c for the transmission controller; and a release switch which unlocks the shift knob.

Abstract: A control system for an automatic transmission of a vehicle is disclosed. The automatic transmission operates in a manual operating mode in which a shift position of the automatic transmission can be changed according to a shift instruction issued by a driver of the vehicle, or in an automatic operating mode in which the shift position is automatically selected. In the control system, a slow running intention of the driver is detected. A first shift position is set to a starting shift position at the time of starting the vehicle when the slow running intention of the driver is not detected in the manual operating mode. A second shift position which is lower in transmission gear ratio than the first shift position is set to the starting shift position when the slow running intention of the driver is detected in the manual operating mode.

Abstract: A control device for a synchromesh automatic transmission comprising: an input shaft 13 driven by a combustion engine 1; an output shaft 16 coupled to the input shaft 13 by gears; a plurality of groups of transmission gears 17 through 21 having different gear ratios and interposed between the input shaft 13 and the output shaft 16; sleeve gears 22a, 22b, and 22c coupling any one of the transmission gears 17 through 21 with the output shaft 16; a shifting and selecting actuator 5 operating the sleeve gears 22a, 22b, and 22c; a shifting and selecting position sensor 6 detecting control inputs in a shifting direction and a selecting direction; and a control unit 4 instructing operations to the above components, wherein the control unit judges whether or not a position of completing the operations is within a range of a target position based on an output from the shifting and selecting position sensor 6 at time of finishing the gear changing operation.

Abstract: Provided are a method of controlling an automobile, an automobile control apparatus, a method of controlling a transmission, a transmission, a transmission control apparatus and a vehicle system, which can reduce affection caused by unevenness among drive power sources and transmission toque changing means and aging effect without using sensors. A power train control unit releases a torque from an engine through an assists clutch so as to release at least a part of a transmission torque of gear trains in order to shift a meshing clutch toward a release position. During the gear release, a load is applied in a direction in which the meshing clutch is shifted toward the release position, before all part of the transmission torque of the gear train is released, and the meshing clutch is shifted to the release position when at least a part of the transmission torque of the gear trains is released.

Abstract: A drive line assembly for a work machine is disclosed. The drive line assembly includes an engine driving an engine output shaft and an engine speed sensor which generates engine speed signals indicative of a speed of the engine output shaft. The drive line assembly further includes a fuel injector operable to regulate fuel flow to the engine and a transmission driven by the engine output shaft and having a number of gear ratios. The drive line assembly yet further includes a controller operable to store a predetermined maximum efficiency curve of engine speed versus torque output and determine the engine speed from the engine speed signals. The controller is further operable to limit the fuel flow the fuel injector supplies to the engine to cause the engine to operate along the predetermined maximum efficiency curve for the engine speed. The controller is yet further operable to control shift points between the number of gear ratios based on the predetermined maximum efficiency curve.

Abstract: A method of controlling an automatic transmission of a motor vehicle operating in a automatic speed control speed mode is provided. The first step in the method is measuring the torque output of the engine. A torque load acting on the transmission in a first gear is then determined. A maximum torque capable of being produced by the engine is then predicted. A torque output of the transmission in a second gear is then determined based upon the predicted maximum torque capable of being produced by the engine. A transmission shift from the first gear to the second gear is then allowed if the determined torque output of the transmission in the second gear is greater than the torque load of the transmission in a first gear.

Abstract: A speed change mechanism (1) constructed by connecting in tandem a hydraulic type speed change unit (17) having a plurality of hydraulic clutches (57, 58, 59) to be alternatively engaged and a hydraulic type speed change unit (20) having a plurality of hydraulic clutches (66, 67, 68) to be alternatively engaged, wherein a time-varying region (common slip region) is secured in which the two clutches slip in common such that during speed change, when the working hydraulic pressure in a clutch to be engaged is on its way to gradual increase, the working hydraulic pressure in a clutch to be disengaged lowers.

Abstract: The invention is directed to a system for adjusting a transmission ratio in a transmission built into a motor vehicle. The system includes at least two transmission ratio criteria with which first transmission ratios are determined based on at least two different determining modes. The system also includes a first arrangement with the aid of which a second transmission ratio is selected in accordance with a pregiven prioritization from the determined first transmission ratios. The transmission ratio is then adjusted in dependence upon the selected second transmission ratio. In an advantageous configuration of the invention, a second arrangement is provided with which the second transmission ratio is modified in accordance with a pregiven strategy. The transmission ratio is then adjusted in dependence upon the modified second transmission ratio.

Abstract: A vehicle control system includes a variable displacement internal combustion engine, a transmission coupled to the variable displacement internal combustion engine, an intake manifold coupled to the variable displacement internal combustion engine, a throttle coupled to the intake manifold, an engine controller for controlling the throttle and the variable displacement internal combustion engine, and a transmission controller for controlling the transmission. The engine controller transfers a throttle position or load value to the transmission controller. This throttle position or load value is independent of the actual displacement of the variable displacement internal combustion engine.

Abstract: Simulated or “mock” continuously variable transmission shift strategies are used in an electromechanically actuated automotive transmission having reduced ratios steps in its upper ratio ranges. In one described embodiment, a 12-speed truck transmission consists of a five-speed main section and an auxiliary section that includes splitter and range sub-sections to provide the 12 ratios. Separate shift strategies are directed to fuel economy and power optimization modes; driver throttle demand determines the mode. Both strategies are targeted to the upper gear ratios, which represent the ratios subject to approximately ninety percent (90%) of vehicular operation. In the described embodiment, the applicable affected ratios are gears 7-12. In the described embodiments, the shift strategies are carried out by embedded software subject to the command of an electronic power train control module.

Abstract: A torque calculator and method for providing real time data that measures net torque output of a running engine in a motor vehicle. Gross torque production is calculated using engine speed and fueling data. Torque losses due to accessories, pumping, and friction are calculated and subtracted from gross torque production, and inertial torque is also accounted for to yield engine net running torque. The engine net running torque data and engine speed data are processed according to a filter algorithm that compensates the engine net running torque data for engine speed. Transmission shifting is controlled by the speed-compensated engine net running torque.

Abstract: A control device is provided for a bicycle having a transmission with a plurality of speed steps, wherein the control device includes a traveling condition signal receiver that receives traveling condition signals corresponding to a traveling condition value of the bicycle, a threshold value memory that stores a first threshold value of the traveling condition, and a processor that compares a plurality of the traveling condition values to the first threshold value and provides a first control signal for shifting the bicycle transmission when the plurality of traveling condition values pass the first threshold value. Additional inventive features will become apparent from the description below, and such features may be combined with the above features to provide additional benefits.

Abstract: To significantly reduce the use of single signal lines using a simplest possible contacting and connecting technique, a control system is described, in which the electrical shifting elements located in the passenger compartment are connected via signal lines to an electronic control unit, which is located in the passenger compartment and linked to the data bus, and which combines the signals transmitted over the signal lines and routes them via the data bus to the transmission control. The outlay for the wiring harness is again greatly reduced, with the data bus now also being routed into the passenger compartment, enabling additional devices to be connected thereto. Accordingly, the control system can be easily expanded.

Abstract: A system for controlling an automatic transmission of a vehicle, wherein the initial value of the desired pressure to be supplied to a hydraulic clutch for the current gear now being engaged is determined appropriately, when conducting a power-on downshifting, so as to decrease the shift shock experienced by the vehicle occupant effectively, irrespectively of the change in the throttle opening, while ensuring to reduce the volume of the mapped data.

Abstract: A control strategy and method for controlling friction element engagement and disengagement time for an automatic transmission when the transmission is operating at cold ambient temperatures. During drive-to-reverse or reverse-to-drive friction element engagements with power on, the strategy compensates for a tendency of an oncoming friction element to gain capacity before an off-going clutch loses capacity, thereby avoiding a potential friction element tie-up condition when the transmission is operated with intermediate or high levels of engine torque as the friction elements are sequentially engaged and disengaged during cold rock cycling.

Abstract: A shift control system for a vehicle automatic transmission includes a vehicle speed sensor for detecting a vehicle speed, and a first control means normally performs a shift control of the transmission so that a target speed ratio of the transmission is achieved, which is determined based at least on a vehicle speed detected by the vehicle speed sensor. The shift control system further includes a second control means that properly performs shift control of the transmission when the vehicle speed sensor is in trouble, by generating a command for holding or changing a current speed ratio based on an input rotation speed of the transmission and/or driver's accelerating or decelerating operation of the vehicle.

Abstract: A method for determining a shift stage (transmission ratio) for a discretely shifting transmission of a motor vehicle wherein an output rpm of the transmission is detected and an optimal motor rpm is pregiven. It is provided that computed and/or measured input rpms (22, 23) of the transmission are detected. An rpm (25, 26) for each shift stage is fixed via a hysteresis circuit (24), a difference of the input rpm (22) of a next-higher shift stage and the rpm (26) supplies an upshift limit (10) and a sum of current input rpm (23) and the rpm (25) supplies a downshift limit (12); and, shifting into a higher shift stage takes place when the upshift limit (10) exceeds the optimal motor rpm (28) or shifting into a lower shift stage takes place when the optimal motor rpm (28) exceeds the downshift limit (12) (shifting necessity (27)).

Abstract: When a deceleration slip executing minimum gear stage is not established in a state of continuously executing a deceleration slip control at a target slip amount, it is judged whether or not an input shaft rotational speed of a transmission becomes a down shift judging rotational speed. When it becomes equal to or less than a predetermined down shift judging rotational speed, a down shift is executed, and a clutch pressure is controlled such that an engine rotational speed becomes a target engine rotational speed.

Abstract: A system for controlling an automatic transmission of a vehicle, wherein a pressure to be supplied to the hydraulic clutch of a target gear is determined based on a desired value of acceleration of gravity acting in the longitudinal direction of the vehicle and other parameters including an engine torque, thereby decreasing the shift shock effectively, while ensuring to finish the shift within an expected period of time. Moreover, the engine torque is estimated using a parameter indicative of inertia torque used for raising the engine speed. With this, it becomes possible to determine the engine torque inputted to the transmission, thereby decreasing the shift shock more effectively.

Abstract: A steer-by-wire gear shifter comprises: a holder; a rotary shaft rotatably held by the holder; a shift lever whose bottom is fixed on the rotary shaft; a shift knob attached to a top of the shift lever; detecting means for detecting an operational condition of the shift knob; an actuator which applies an external force for force feedback to the shift knob through the rotary shaft and the shift lever; a control section which receives a detection signal a from the detecting means, a transmission signal d from a transmission controller and an engine revolution speed signal e from an engine controller, generates and outputs a control signal b for the actuator and a gear shift signal c for the transmission controller; and a release switch which unlocks the shift knob.

Abstract: A shift control method and a system thereof of an automatic transmission equipped with a manual shift lever apply a modified shift pattern when a vehicle driving state satisfies a predetermined condition for changing a shift pattern during driving in a second speed range “22”. This allows shifting to be managed suitably when a vehicle is either in a heavy-load state or a base state.

Abstract: A control apparatus of an automatic transmission capable of achieving a smooth change of output shaft torque to torque which can be generated by a friction clutch, thus enabling a smooth gear change even if the output shaft torque is high at the gear change. If the output shaft torque exceeds limit transmission output shaft torque obtained by multiplying a torque capacity of the friction clutch by a gear ratio provided for the friction clutch when a gear change command is issued in the automatic transmission, engine torque is controlled so as to make the output shaft torque decreased to the limit transmission output shaft torque, and then the engine torque control is switched when the output shaft torque decreased to the limit transmission output shaft torque to start the gear change operation.

Abstract: A transmission comprises an engine, which is controllable to stop under a predetermined condition, and a speed change mechanism TM, which transmits the output rotation of the engine at different speed ratios. The speed change mechanism TM has a plurality of transmission paths (the LOW ratio, the SECOND speed ratio, etc.) disposed in parallel, a plurality of ratio-setting clutches (the LOW clutch 11, the SECOND speed clutch 12, etc.), each clutch for selecting a predetermined transmission path, and a speed change control system for selectively supplying a hydraulic pressure to any of the ratio-setting clutches to bring it into engagement. Engagement-initiation time is calculated for each ratio-setting clutch, so that the ratio-setting clutch requiring a minimum engagement-initiation time is selected as the clutch for the start-up speed ratio. When the engine is restarted from stopped state, this clutch for the start-up speed ratio is supplied with oil.

Abstract: A torque calculator and method for providing real time data that measures net torque output of a running engine in a motor vehicle. Gross torque production is calculated using engine speed and fueling data. Torque losses due to accessories, pumping, and friction are calculated and subtracted from gross torque production, and inertial torque is also accounted for to yield engine net running torque. The engine net running torque data and engine speed data are processed according to a filter algorithm that compensates the engine net running torque data for engine speed. Transmission shifting is controlled by the speed-compensated engine net running torque.

Abstract: A transmission unit is composed of an engine E, a torque converter TC, and an automatic transmission TM. The engine restart and vehicle start control apparatus comprises an electromagnetic valve capable of calculating the pump impeller suction torque of the torque converter and setting the oil pressure increase ratio for the oil pressure supplied to the vehicle start clutch. When the engine is restarted from an engine stopped state and the vehicle start stage is set by supplying hydraulic oil to a friction engagement element and engaging the friction engagement element, an oil pressure supply increasing at a first oil pressure increase ratio is conducted till the calculated pump impeller suction torque reaches the prescribed criterial value, and an oil pressure supply increasing at a second oil pressure increase ratio which is less than the first oil pressure increase ratio is conducted from the instant the calculated pump impeller suction torque becomes greater than the prescribed criterial value.

Abstract: A control system for a utility vehicle, particularly a compact utility tractor, that is speed-controlled by a hydrostatic transmission, prevents engine stalling by automatically reducing the stroke of a pump of the hydrostatic transmission, and thus reducing the vehicle speed, when the unloaded engine speed drops below a predetermined threshold. The apparatus includes a servo controlled hydrostatic transmission, an engine speed sensor, a throttle position sensor and a controller. The unloaded engine speed is determined by either an engine throttle lever position or by an engine speed capture algorithm that continuously monitors engine speed and records engine speed occurring when the transmission control pedals are positioned in neutral.

Abstract: A method for controlling the capacity of friction clutches and brakes in a multiple-ratio vehicle transmission and for simultaneously establishing ratio shift point scheduling to effect a desired vehicle speed at which ratio changes occur while the vehicle is in a traction control mode. The method includes calculating a synthetic throttle setting that is used to establish clutch and brake capacity control and wherein separate ratio shift schedules are used for normal operation and for traction control operation, the engine torque required during operation in the traction control mode determining the vehicle speed at which shifts occur for each gear ratio whereby the shift schedule during operation in the traction control mode can be calibrated independently of the throttle position required for optimum clutch and brake capacity control.

Abstract: A vehicular automatic transmission TM has a torque converter TC connected to the engine E and an automatic transmission mechanism (gear trains 13a, 13b, 14a, 14b) connected to the output side of the torque converter, the drive power from the engine for which gear shifting is performed via the torque converter and the automatic transmission mechanism is transmitted to the wheels and the vehicle is driven. The control apparatus for this automatic transmission mechanism has towing state presumption means that presumes based on the driving conditions that the vehicle is in a towing state, and a lockup engagement increase mechanism that increases the degree of engagement of the lockup clutch of the torque converter when it is determined via the towing state determination means that the vehicle is in a towing state.

Abstract: An improved powertrain control minimizes output torque disturbances due to garage shifting. Under certain predefined conditions, garage shifts to the forward or Drive range are carried out by initially commanding a shift to an upper forward gear ratio having a relatively low torque advantage, and then commanding a shift from the upper forward gear ratio to a lower forward ratio that is ordinarily used to launch the vehicle. The shift from the upper gear ratio to the lower gear ratio is initiated when the initial shift is substantially complete or when a predetermined period of time has elapsed since shift initiation. Engine management controls are also used to reduce the transmission input torque during garage shifts to both forward and reverse ranges.

Abstract: According to the method for controlling at least one power-shift multi-speed boat transmission in conjunction with a fixed propeller or water jet, the upshift speed is a function of a value which indicates the intended acceleration, especially a function of the regulating speed of the control lever or the speed of modification of the transmission input speed.

Abstract: A control for shifting into a start ratio in a computer-assisted (48) vehicular splitter-type compound transmission (16) having a main section (16A) shifted by a manually operated shift lever (31) and a controller (42). The splitter section (16E) is provided with a three-position (L, H, N) actuator (46) and is commanded to a splitter-neutral position upon sensing a main section shift to neutral, master clutch (14) disengagement and low vehicle speed (OS<REF<3 MPH) to reduce the inertia of the main shaft assembly and reduce the need for a clutch brake when engaging a start ratio.

Abstract: A method for controlling an automatic transmission in a drive train of a motor vehicle having a transmission controller selecting and shifting gears of the transmission includes determining a new gear by reference to gear shift characteristic curves and generating a gear shift instruction as soon as a working point of the drive train exceeds a gear shift characteristic curve. The transmission controller determines a new gear that is expected to be engaged shortly. If the new gear differs from the current gear, an initial phase of the gear shift is carried out and the gear shift is completed as soon as the gear shift instruction has been generated. The initial phase is carried out as soon as the working point drops below a predefined distance from the gear shift characteristic curve.

Abstract: An automatic transmission controller is capable of compensating for both driver type and tendencies of a driver in temporary acceleration, such as in passing. The automatic transmission controller executes a driver type judging subroutine for judging the overall acceleration habits of the driver and classifying the driver as one of a plurality of driver types by monitoring the driving behavior for a predetermined time. The controller also executes a temporary acceleration inclination judging routine for judging the habits of the driver in temporary acceleration by monitoring driving behavior for a period of time shorter than the predetermined time, and executes shift control routines for controlling and changing the shift timing based on the judged driver type and the inclination in temporary acceleration. The controller controls shift timing, taking into account both the driver type and the inclination in temporary acceleration, such as passing.

Abstract: An apparatus and a method for controlling an automotive vehicle are disclosed, in which a control amount for securing safety of the vehicle and the control amount for achieving a state intended for by the driver of the vehicle are switched in such a manner as to reduce the shock due to the change in the torque generated from the power train, thereby accomplishing both safety and maneuverability at the same time. A first target value is set for controlling at least selected one of the driving torque, the driving force and the acceleration/deceleration rate. A second target value is calculated in accordance with the drive mode intended for by the driver or the driving environment ahead of the vehicle. In the case where a deviation exceeding a predetermined value develops between the first target value and the second target value, the fluctuations of at least one of the driving torque, the driving force and the acceleration/deceleration rate are suppressed.

Abstract: An engine control apparatus includes a brake depression degree detecting device for detecting a degree of depression of a brake pedal in a vehicle. A brake depression degree judging device operates for judging whether or not the detected degree of depression of the brake pedal is smaller than a prescribed value. A deceleration detecting device operates for detecting a deceleration of the vehicle. An automatic engine stop and restart controlling device operates for automatically stopping an engine powering the vehicle when the deceleration detecting device detects a deceleration of the vehicle and the brake depression degree judging device judges that the detected degree of depression of the brake pedal is not smaller than the prescribed value.

Abstract: The invention proceeds from a system for adjusting a motor vehicle transmission, which is changeable in its transmission gear ratio, the transmission having an efficiency characteristic which is dependent on the transmission gear ratio. A first quantity is detected which represents the actual transmission output rpm and a second quantity is determined which represents a desired value for the drive torque. Then, a desired rpm of the vehicle engine is determined at least in dependence upon the detected first quantity and the determined second quantity and in dependence upon the efficiency characteristic of the transmission. The adjustment of the transmission gear ratio takes place in dependence upon the desired rpm of the vehicle engine which is so determined. With the invention, transmission influences are considered in the determination of the optimal transmission gear ratio within a system for the coordinated drive train control.

Abstract: The invention relates to a method for determining a starting gear step for a vehicle with a multi-speed stepped variable transmission, wherein the starting gear step is determined by an electronic control device which is dependent on the vehicle mass; and a second variable which depends on the vehicle state is determined from the vehicle mass, the current traction and the current vehicle acceleration resulting therefrom.

Abstract: In an automatic transmission in which an input shaft torque of the automatic transmission is estimated from an engine torque and an oil pressure during a period of gear change is controlled corresponding to the input shaft torque, the estimation value of the input shaft torque is held to a value immediately before a gear change judgment until a period of time from the gear change judgment until a changing speed of an engine rotation speed exceeds a predetermined value, and when the changing speed exceeds the predetermined value, an estimation value of the engine torque is processed by a low pass filter having a time constant corresponding to the engine rotation speed, thereby the estimation value of the input shaft torque based on the estimation value of the engine torque passing through the low pass filter.

Abstract: The present invention is to reduce a shift shock occurring while shifting from a reverse driving range to a forward driving range, and to improve durability at the same time.

Abstract: In the operation of work machines it has been a problem to control the work machine's velocity aspects such as velocity, acceleration, deceleration and jerk because of the plurality of operator interfaces required for such control. The present invention provides an operator interface system for a work machine in which a first pedal is displaceable from a neutral position, and a sensor is operatively coupled with the first pedal and is operable to output a displacement signal corresponding to a location of the first pedal. An electronic controller receives the displacement signal and provides a pre-determined control to a velocity aspect of the work machine in response to the displacement signal.

Abstract: A speed change control device for an automatic transmission wherein the speed ratio is automatically varied according to a running state when an automatic shift mode is selected, and the speed ratio is varied based on a manual operation when the manual shift mode is selected. When there is a change-over from the automatic shift mode to the manual shift mode, a speed ratio immediately after the change-over is set to a speed ratio such that a transmission input rotation speed after the change-over increases by at least a predetermined rotation speed compared to the transmission input rotation speed before the change-over. In this way, the effectiveness of engine braking is enhanced immediately after a change-over to the manual shift mode, or a downshift for acceleration can be definitively performed.

Abstract: For an automatic transmission (2), a safety system is proposed in which a virtual reduction ratio is calculated when a driver moves the selector lever from a drive position to neutral and then from neutral back to a drive position. The virtual reduction ratio is then compared with the reduction ratio resulting from a shift characteristic field. In case of divergence, the virtual reduction ratio is assigned to a characteristic field having a linearly constant reduction ratio surrounded by a reduction ratio range. The electronic control unit (5) selects as a set reduction ratio, the one containing in its range the virtual reduction ratio.

Abstract: A shift control method for an automatic transmission based on one of a first shift pattern based on vehicle speed and an opening degree of a throttle valve and a second shift pattern based on the vehicle speed and a road condition includes the steps of switching a vehicle shifting condition to the second shift pattern when the opening degree of the throttle valve is a first predetermined opening degree or smaller than the first predetermined opening degree, and switching the vehicle shifting condition to the first shift pattern when the opening degree of the throttle valve is a second predetermined opening degree or larger than the second predetermined opening degree which is larger than the first predetermined opening degree.

Abstract: The invention relates to a method for taking up play in a drive system when a change in load occurs. The drive system comprises a drive engine, preferably an internal combustion engine, coupled to a drive line in a vehicle, an electric motor which acts on the drive engine and/or the drive line with a driving or braking torque, and which motor is coupled to the drive engine or constitutes a part of the drive line, and a control system for controlling the electric motor. The control system sends a pulse to the electric motor when a change in load occurs, a torque pulse taking up play in the drive line before a torque stage from the drive engine begins. The size of the pulse is selected from a matrix stored in a memory, depending on the current operating conditions. The invention also relates to an arrangement for implementing the method.

Abstract: An improved accessory drive device is disclosed where the device will provide a substantial portion of the rated capacity at idle speed, essentially full capacity at a fast or tactical idle speed and will resume normal operating characteristics at highway speeds. The device will revert to the higher yield idle mode when the vehicle remains at idle for a predetermined time.