Abstract: Provided is a vehicle control method in which a controller executes sailing stop control in which, if the conditions for stopping a drive source are satisfied during travel, the drive source is stopped and a coupling element provided in a power transmission path between the drive source and a continuously variable transmission is released for coasting. If the conditions for stopping the drive source are not satisfied, the controller restarts the drive source and estimates the driver's intention to accelerate, and if the driver has an intention to accelerate, the gear ratio of the continuously variable transmission is increased to a higher value than when there is no intention to accelerate, and the coupling element is coupled.

Abstract: The invention realizes a gateway device capable of shortening the time required for routing to a CAN bus of the opposite microcomputer side and reducing the delay of data transfer. If the indexes are the same, a microcomputer 1 and a microcomputer 2 include common routing tables 10 and 20 in which the same contents are defined. The microcomputer 1 sends the index to the microcomputer 2. The microcomputer 2 that has received the index reads the routing rule defined in the common routing table 20 by the received index.

Abstract: A hydraulic system for an automatic transmission of a motor vehicle. A high-pressure circuit, in which a pressure accumulator, at least one clutch, and gear selectors and a hydraulic pump, which can be operated by an electronic control unit and by which the accumulator pressure in the high-pressure circuit can be increased in charging operation. A clutch valve that can be operated by the control unit is arranged in a clutch path between the pressure accumulator and a clutch hydraulic cylinder of the clutch, using which clutch valve a hydraulic pressure applied to the clutch hydraulic cylinder can be adjusted, and a safety valve that can be operated by the control unit is arranged upstream of the clutch valve.

Abstract: A control method of a continuously variable transmission mounted on a vehicle includes performing advance compensation in a speed ratio control system of the continuously variable transmission, and making an advance amount according to a vibration frequency of torsional vibration of an input shaft of the continuously variable transmission which is the advance amount of the advance compensation variable in accordance with an operation state of the vehicle. A feedback gain of speed ratio control of the continuously variable transmission performed in the speed ratio control system is variable in accordance with an operation state of the vehicle. When the advance amount is made variable, the advance amount is made variable in accordance with the feedback gain.

Abstract: An electronic controller for a variable ratio transmission and an electronically controllable variable ratio transmission including a variator or other CVT are described herein. The electronic controller can be configured to receive input signals indicative of parameters associated with an engine coupled to the transmission. The electronic controller can also receive one or more control inputs. The electronic controller can determine an active range and an active variator mode based on the input signals and control inputs. The electronic controller can control a final drive ratio of the variable ratio transmission by controlling one or more electronic solenoids that control the ratios of one or more portions of the variable ratio transmission.

Abstract: There is disclosed a continuously variable ratio transmission assembly (“variator”) comprising a roller which transmits drive between a pair of races, the roller being movable in accordance with changes in variator ratio, a hydraulic actuator which applies a biasing force to the roller, at least one valve connected to the actuator through a hydraulic line to control pressure applied to the actuator and so to control the biasing force, and an electronic control which determines the required biasing force and sets the valve accordingly, wherein the valve setting is additionally dependent upon a rate of flow in the hydraulic line.

Abstract: A method for identifying a driving resistance of a motor vehicle includes the steps of recording values of control and/or state variables of the vehicle during a driving state of the vehicle when a control route is covered, adapting parameters of a vehicle model and/or a model of the area surrounding the vehicle on the basis of the values of the recorded control and state variables, identifying the driving resistance on the basis of the adapted vehicle model and/or the surrounding area model, wherein the parameters of the vehicle model and/or the surrounding area model are adapted on the basis of a distinction between driving states, wherein these driving states include a driving state of a closed drive train with a positive driver demand torque, a driving state of a closed drive train without a positive driver demand torque, and/or and a driving state with an open drive train.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: An HV-ECU performs a step of detecting an atmospheric pressure, a step of calculating a maximum value of a boost voltage corresponding to the atmospheric pressure by using a map, and a step of setting the maximum value as a system voltage value and controlling a DC/DC converter. Moreover, the HV-ECU may calculate a resistance value of a gate resistance of a switching element corresponding to the atmospheric pressure by using the map and control the gate resistance to achieve the set resistance value.

Abstract: An exemplary control device includes an input torque detection unit that detects an input torque input to the input shaft; and a controller that: determines torque distribution of two of the friction engagement elements that form the shift speeds; and calculates a transmission torque of the two friction engagement elements based on the input torque and the torque distribution and sets the engagement pressure to obtain a torque capacity that can transmit the transmission torque, wherein the controller sets the engagement pressure such that slippage does not occur in the two friction engagement elements in a state where engagement of the two friction engagement elements forms the shift speeds and such that, even if an additional friction engagement element engages based on the line pressure while the two friction engagement elements are engaged, one of the three friction engagement elements is caused to slip.

Abstract: A control apparatus for a shift-position changing mechanism that changes the shift positions of an automatic transmission mounted in a vehicle using a rotational force of an actuator based on a signal corresponding to the state of an operation member, including: a mechanism that generates a rotational force for moving the actuator toward a rotation stop positional-range corresponding to the shift position, based on a rotation stop position of the actuator; a detection unit that detects a rotation amount of the actuator; a control unit that controls the actuator based on the signal and the detected rotation amount; and a learning unit that learns the rotation stop positional-range corresponding to the shift position, based on an amount by which the actuator has been rotated since a control over the actuator executed by the control unit is stopped.

Abstract: A method of controlling an automated step-down transmission, arranged in a drivetrain between an engine and a drive axle, which includes a multi-stage main transmission and a range group. The main transmission has an intermediate transmission style with a countershaft having a transmission brake and an input shaft connected, via a clutch, to the engine. The main transmission shifts, without being synchronized, and the range group shifts, after synchronization, such that the engaged gear ratio of the main transmission remains engaged during a range shift operation. The range shift is accomplished by firstly reducing drive engine torque; secondly, disengaging the existing gear ratio of the range group; thirdly, remotely synchronizing the target gear ratio in the range group; fourthly, engaging the target gear ratio in the range group; and fifthly, increasing the drive engine torque.

Abstract: In the case where a belt return of a continuously variable transmission is not determined when the vehicle speed has become equal to or lower than a threshold value, control that causes a hydraulic actuator to have an intermediate pressure by setting a duty of a duty solenoid based on an input torque and an oil temperature and closing control are repeatedly performed, in accordance with the running and the stopping of the vehicle. As a result, it is possible to inhibit the continuously variable transmission from being shifted up due to a gradual increase in the hydraulic pressure in the hydraulic actuator caused by a line pressure seeping to the hydraulic actuator side through a small clearance in a spool of a flow rate control valve in a hydraulic circuit, and it is also possible to allow the continuously variable transmission to be shifted down.

Abstract: In an embodiment of the continuously variable transmission control apparatus of the present invention, even if an actual gear change ratio RATIO overshoots a target gear change ratio RATIO T and an upshift gear change instruction (DS1 gear change duty output) is switched to a downshift gear change instruction (DS2 gear change duty output) during gear change due to the upshift gear change instruction, in the case where the upshift gear change speed is fast, specifically, in the case where a maximum actual sheave position change ratio DWDRmax is not less than a determination threshold g, it is determined that the transmission is capable of performing an upshift gear change, and the upshift gear change state is determined to be normal. In this manner, a normalcy determination is performed more frequently.

Abstract: A hydraulic control apparatus of a belt-drive CVT, controlling a transmission ratio by changing respective effective rotation radii of driving and driven pulleys, includes vehicle information sensors; hydraulic actuators changing the respective rotation radii; and a control unit determining each fluid pressure command value provided for the pulleys, and controlling the hydraulic actuators based on the fluid pressure command values. The control unit acquires an actual displacement amount of one of the pulleys. When changing a transmission to the highest or lowest speed transmission, the control unit sets a target displacement amount of one of the pulleys; estimates a rapidly changing amount of the working fluid pressure, occurring at close to an end of the speed change; and corrects the fluid pressure command value by the rapidly changing amount at a time when a rate of the actual displacement amount with respect to the target displacement amount has reached a predetermined rate ?0.

Abstract: A hydraulic system for controlling a belt-driven conical-pulley transmission of a motor vehicle, wherein the transmission has a variably adjustable transmission ratio. The hydraulic system includes a first valve arrangement to control a contact pressure in the belt-driven conical-pulley transmission, a second valve arrangement to control the transmission ratio of the belt-driven conical-pulley transmission, and a hydraulic energy source to supply the hydraulic system with hydraulic energy. In order to provide an improved hydraulic system, the system includes a third valve arrangement for controlling a forward clutch and a reverse clutch.

Abstract: Restriction of hunting in the gear ratio of an electronically-controlled continuously variable transmission (ECVT) for a vehicle. A gear ratio change mechanism has a crankshaft as an input shaft, an output shaft and a motor. The motor continuously varies the gear ratio between the crankshaft and the output shaft. An electronic control unit (ECU) performs feedback control of the gear ratio to achieve a target gear ratio. The ECU reduces an output of the motor when a hunting state of the gear ratio is detected.

Abstract: An object of the present invention is to avoid unnecessary accumulation of a correction value during feedback control, even when a secondary pressure control valve enters a state of failure. A continuously variable transmission comprises a primary pulley supplied with a primary pressure that has been adjusted via a primary pressure control valve, a secondary pulley supplied with a secondary pressure that has been adjusted via the secondary pressure control valve, and a drive belt wound around the two pulleys. When a failure such as a disconnection occurs in the secondary pressure control valve, a lower limit value Imin of a target gear ratio is raised to a low side by a CVT control unit, and a setting region of the target gear ratio is set in a low region in which control is possible even during a failure. In so doing, divergence between the target gear ratio and an actual gear ratio can be avoided, and therefore unnecessary accumulation of the correction value during feedback control can be avoided.

Abstract: In control apparatus and method for an automotive vehicle, the vehicle having a continuously variable transmission associated with a vehicular engine and including a belt that transmits a revolution of a primary pulley to a secondary pulley that is enabled to make a gear shift by modifying a pulley ratio between the primary and secondary pulleys with a hydraulic, a determination is made as to whether a belt slip between at least one of the primary and the secondary pulleys occurs and an output section outputs a signal to command an engine control unit to increase an engine speed by a predetermined engine speed when the belt slip is determined to occur.

Abstract: When a target duty of a solenoid valve of an automatic transmission of a vehicle lies in a predetermined duty range, the solenoid valve is driven for an adjusted over-excitation period obtained by adjusting a base over-excitation period on the basis of an over-excitation period adjusting value. Therefore, the solenoid valve may be normally controlled in a region in which it shows an abnormal response characteristic.

Abstract: A control system for a continuously variable transmission provided with a first pulley (1) having two pulley discs (5, 7), with a second pulley (2) having two pulley discs (6, 8) and with a drive belt (10) wound around said pulleys (1, 2) for transmitting torque there between, at least one disc (7) of the first pulley (1) being axially movable with respect to the other disc (5) of the pulley (1) under the influence of an axial force provided on the movable disc (7) by a line pressure (PLP) in a cylinder (11) of a piston/cylinder assembly (11, 13) associated with the the first pulley (1) and at least one disc (6) of the second pulley (2) being axially movable with respect to the other disc (8) of the pulley (2) under the influence of an axial force provided on the movable disc (8) by a second cylinder pressure (P2CP) in a cylinder (12) of a piston/cylinder assembly (12, 14) associated with the the second pulley (2).

Abstract: A speed change control system for a continuously variable transmission, for controlling a gear ratio by deciding an abrupt acceleration demand of a driver, to effect an abrupt speed change when it is decided that the driver demands an abrupt acceleration. The speed change control system comprises: a drive state decider for deciding that the vehicle has changed from a driven state to a drive state, when said abrupt acceleration is demanded at the driven state; and a speed change controller for controlling said continuously variable transmission to effect said abrupt speed change, after said drive state decider decides that the vehicle has changed from the driven state to the drive state.

Abstract: A shift control apparatus for a motor vehicle including an Internal combustion engine and a continuously variable transmission (CVT) is provided for controlling the speed ratio of the CVT depending upon operating conditions of the vehicle. The control apparatus determines whether an electronic throttle valve of the engine is at fault or not, and restricts the speed ratio of the CVT when the throttle valve is at fault such that the input-side rotation speed of the transmission is variable within a range that is narrower than a range in which the rotation speed is variable during normal running of the vehicle. The range of the input-side rotation speed may be defined by the upper limit, or the lower limit, or both the upper limit and the lower limit.

Abstract: An electronic transmission control system for an automotive vehicle with a belt-type continuously variable automatic transmission comprises a transmission ratio control device including a first motor-driven oil pump supplying working pressure directly to a secondary pulley actuation chamber, and a second motor-driven oil pump supplying working pressure directly to a primary pulley actuation chamber and enabling working oil to come and go between the primary and secondary pulley actuation chambers therethrough. A first control section is provided for controlling the first motor-driven oil pump with feed-forward compensation for the working pressure supplied to the secondary pulley actuation chamber, based on changes in a flow rate of the working oil coming and going between the primary and secondary pulley actuation chambers, so that the secondary pulley pressure is regulated as a belt capacity holding pressure needed to hold a belt capacity of the drive belt in a first motor-driven pump side.

Abstract: A control system controls a line pressure applied to a CVT upon taking account of a certrifugal pressure caused by a rotation of pulleys. The control system determines whether the centrifugal pressure is greater than a predeterminied value only by which the pulley transmits an input torque from an engine. When the determination is affirmative, a lower limit of a duty ratio for operating a line pressure control valve is switched from a lower limit of a linear range to 0% duty ratio. Therefore, an actual transmissiou ratio control range is expanded while preventing an undershoot of the line pressure.

Abstract: In the process according to the invention for predetermining the ratio of a continuously variable transmission (5), a dynamic driving range is generated. The actual, minimum and maximum acceleration (a_akt, a_min, a_max) is calculated. Further detected is the driver's wish to accelerate or to decelerate (a_fwu) and an acceleration (a_vorg) is determined. Also calculated is a change of ratio per time unit of the continuously variable transmission (iV_pkt), which is guided by the engine speed of rotation during adjustment of the continuously variable transmission (5).

Abstract: A controller (61) calculates a transient target speed ratio based on a final speed ratio set according to a vehicle running condition and second order delay time constant gains (75, S99), and control a speed ratio of a continuously variable transmission to the transient target speed ratio via an actuator (4) (87, S103). The controller (61) also calculates the deviation between the final target speed ratio and transient target speed ratio (74, S95), and determines the second order delay time constant gains based on the deviation (74, S98). Preferably, the gains are determined so that the response rate is slower the larger the deviation (74, S134, S135, S136, S137, S139, S140, S141).

Abstract: An electronic transmission control system having a fail-safe system for an automotive vehicle with a continuously variable automatic transmission whose speed-change ratio is changeable continuously depending on vehicle speed and engine load, comprises a hydraulic modulator producing at least a regulated line pressure necessary to adjust the speed-change ratio hydraulically, a desired speed-change ratio arithmetic processing section for calculating a desired speed-change ratio based on the vehicle speed and the engine load, and a desired line pressure arithmetic processing section for calculating a desired line pressure based on the desired speed-change ratio and the engine load.

Abstract: A shift control apparatus outputs a command transmission ratio to a continuously variable transmission (CVT) to control a real transmission ratio of the CVT. The shift control apparatus comprises a shift mode determining section determines whether an actually selected shift mode is an automatic upshift or a power-down upshift (foot-release upshift), on the basis of the result of a previously selected shift mode, a difference between a final objective transmission ratio and a transient objective transmission ratio and a rate of change in the transmission ratio per time. The dynamic characteristic selecting section determines the dynamic characteristic according to the determined shift mode.

Abstract: A continuously variable transmission control system determines the desired speed ratio for a continuously variable transmission from various input data received from the vehicle and operator. The desired speed ratio is compared with a commanded speed ratio to provide an error signal which establishes a new commanded speed ratio for the continuously variable transmission. The comparing process of desired speed ratio to commanded speed ratio is repeated until the error signal is substantially null. Also, the control provides an adaptive modifier for the actuator of the continuously variable transmission such that a comparison of actual transmission ratio to commanded speed ratio will determine if an adaptive modification is necessary. The control further provides a step control function which is operable when the ratio of the continuously variable transmission is moving toward an underdrive ratio.

Abstract: An apparatus for controlling a dynamic system, for example, a continuously variable transmission for an automotive vehicle which adjusts a gear ratio by bringing a pulley position of a primary pulley into agreement with a target one through a hydraulic system under the feedforward and sliding mode control is provided. The apparatus calculates a feedforward-controlled variable in addition to a feedback-controlled variable and adjusts the pulley position of the primary pulley to a target one using the hydraulic pressure provided based on the sum of the feedforward-controlled variable and the feedback-controlled variable, thereby enhancing the robustness of the sliding mode control without causing the hunting.

Abstract: A continuously variable transmission in a motor vehicle is regulated using a controller comprising a first control circuit as a speed controller for regulating the transmission input speed as the product calculated from the transmission output speed and the transmission ratio, complete with a summation element at the controller input as well as with a control element, and a second control circuit post-connected to the first control circuit as a speed gradient controller for regulating the time derivative of the transmission input speed, complete with a summation element at the controller input.

Abstract: A hydraulic control apparatus for a continuously variable transmission which can produce stable drive pulley pressure and driven pulley pressure and also control the speed change time. The line pressure regulated by the regulator valve 22 is supplied to the control valve 24.sub.DR of the drive pulley 5 and to the control valve 24.sub.DN of the driven pulley 7. These control valves regulate the line pressure according to the PB pressure and the PC pressure output from the solenoid valves SOL-B, SOL-C, respectively, and produce the drive pulley pressure P.sub.DR and the driven pulley pressure P.sub.DN. When the PB pressure and the PC pressure are both zero, and P.sub.DR =P.sub.DN, the control apparatus maintains the same gear ratio. When the PB pressure is increased from zero while keeping the PC pressure at zero, i.e. P.sub.DR >P.sub.DN, the gear ratio changes toward the high-speed overdrive. When the PC pressure is increased from zero while holding the PB pressure at zero, i.e. P.sub.DR <P.sub.

Abstract: The invention is directed to a system for automatically adjusting the gear ratio of a continuously variable transmission mounted next to the motor of a vehicle. The gear ratio is adjusted with a specific speed. The essence of the invention is that a mechanism is provided which facilitates a determination of the speed of the adjustment of the gear ratio of the transmission in dependence upon detected operating parameters. With the system of the invention, an adjustment characteristic of the transmission is obtained which is comfortable for the driver of the vehicle.

Abstract: A gear shift control device of an automatic transmission of a vehicle, including: a means for estimating a target shift stage for harmonizing rotation speed and power output of engine of the vehicle; a means for estimating slip angle of at least one of the pair of drive wheels; a means for estimating slip ratio of the at least one drive wheel which would be caused thereon by the automatic transmission being shifted to the target shift stage; a means for estimating tire grip of the at least one drive wheel based upon the estimated slip angle and the estimated slip ratio; a means for judging if the estimated tire grip of the at least one drive wheel is in a grip range predetermined therefor; and a means for executing gear shift of the automatic transmission when the target shift stage is different from a current shift stage with the estimated tire grip being within the predetermined grip range.

Abstract: A steady state transmission ratio Base i is computed from a vehicle speed VPS and a throttle opening TVO (S1). An output shaft revolution speed No of the transmission and a current transmission ratio i are detected (S2, S3). A coefficient TTINR is computed from a difference or a ratio or the like between the steady state transmission ratio Base i and the current transmission ratio i (S4). Then, from the current transmission ratio i, the output shaft revolution speed No and the coefficient TTINR, a shift speed SV=TTINR/(IE.times.i.times.No) is computed (S5). Then a shift control is performed in accordance with the shift speed SV so as to approach to the steady state transmission ratio Base i (S6.about.S9). Thus, the shift speed during shifting in a continuously variable transmission is controlled in consideration of inertia torque.

Abstract: By a controller which controls a speed-change control valve for switching a hydraulic pressure to be supplied to each of cylinder chambers of each of pulleys of a continuously variable vehicular transmission, the speed reduction ratio is controlled such that the engine revolution speed becomes a target revolution speed which is set depending on the running conditions of a vehicle. When an accumulated time of high-speed operation at which Ne becomes higher than a predetermined first set revolution speed exceeds a first set time, an upper limit value of Ne or the target revolution speed is corrected to decrease. Further, when the duration time of a low-speed revolution below a predetermined second set revolution speed which is smaller than the first set revolution speed exceeds a second set time, the upper limit value of Ne is corrected to increase or the correction to decrease the target revolution speed is stopped.

Abstract: The invention improves the driveability of a vehicle by controlling a target engine speed according to an engine load and a vehicle running condition to ensure an actual engine speed. In controlling a speed ratio of a continuously variable transmission, an adaptation factor is used for deciding a target engine speed, the adaptation factor is determined according to constants, an average engine load and an average vehicle speed change quantity. Even when the average engine load changes because of fluctuation in an accelerator opening, various running modes can be decided by the adaptation factor depending upon both the average engine load and the average vehicle speed change quantity, thereby improving driveability upon changing speed of the continuously variable transmission.

Abstract: An automatic transmission of a vehicle including a speed change gear mechanism including rotary members such as gears and gear carriers and hydraulically operated friction engaging means and adapted to provide various speed stages according to selective engagement and disengagement of the friction engaging means is controlled by such steps as detecting rotation speed of at least one of the rotary members during a shifting between the speed stages, changing hydraulic pressure of at least one of the friction engaging means during a first phase of the speed stage shifting so as to make the rotation speed of the one rotary member follow a first change performance curve calculated according to a first feedback control program, and changing the hydraulic pressure of the one friction engaging means during a second phase of the speed stage shifting so as to make the rotation speed of the one rotary member follow a second change performance curve calculated according to a second feedback control program in continuity

Abstract: A method for controlling an automatically actuated transmission for a motor vehicle, for improving behavior before curves and during braking, provides that a coasting function to suppress a shift or gear ratio changing process is initiated as soon as the accelerator pedal is quickly released. This coasting function is maintained until powered operation is again detected and the vehicle accelerates. Then a holding time is started during which the coasting function is started again as soon as the vehicle changes to coasting operation.The method is applicable to multi-step transmissions as well as continuously variable transmissions.

Abstract: In a non-stage transmission control system, the output current instruction signal of a microcomputer is provided as a pulse-width-modulated signal, with a result that the number of signal lines from the microcomputer is reduced. Furthermore, the current feedback signal of a solenoid is applied to the microcomputer, for detection of abnormal conditions, and a quick break resistor is connected in series to a feedback diode to increase the current reduction rate of the solenoid.

Abstract: A control system for a friction bypass clutch for a torque converter that forms a part of an infinitely variable transmission in a vehicle driveline having an internal combustion engine including closed loop electronic controllers for coordinated control of the speed ratio of the transmission and the rate of engagement of the torque converter bypass clutch so that the resulting turbine speed will cause the vehicle engine to operate at an ideal speed and throttle setting that will achieve maximum brake specific fuel consumption wherein the time required for reaching the ideal speed is longer than the time required to complete engagement of the bypass clutch, thus effecting smooth clutch engagement with reduced energy absorption.