摘要:
A control system (in FIG. 1A) for a motor vehicle having a continuously variable transmission, in which a control of better fuel consumption is selected between the retardation angle correction (the correction of the retardation angle side of an advance angle correction) of the ignition timing of an internal combustion engine and the increase correction of the target r.p.m. of a continuously variable transmission, and the selected control is executed, whereby the fuel consumption of the engine is relieved from worsening in a control for the prevention of knocking or for the suppression of NOx in emission.
摘要:
A downstream rate limiting control is provided for controlling a continuously variable transmission. The rate limiting control monitors a input and a current machine state and computes the difference between these two inputs and compares the computed error to a predefined rate table to determine if the computed error should be limited or modified. The rate signal will modify the computed error within the control logic with respect to operator comfort and machine parameters.
摘要:
In order to improve steering performance and braking performance specifically on a low .mu. road surface during operation of engine braking, there are provided, in a shift control system of a continuously variable transmission, a sensor for determining a wheel deceleration, and a shift controller for changing a shift pattern adequately. When an engine brake range such as a 2 range or an L range is selected, and the wheel deceleration becomes greater than a predetermined deceleration level, the shift controller changes an upshift limit of the engine brake range, to a smaller transmission ratio. By reducing the transmission ratio in this way, the shift control system can reduce an engine braking force applied to the drive wheels and an inertia torque of the transmission against the driving force applied to the drive wheels by the road surface, so that the wheel speed can readily increase to achieve a desirable degree of wheel slip.
摘要:
An electronic transmission control system for a self-propelled off-road vehicle having an internal combustion engine and multiple gear powershift transmission controls the powershift transmission and provides the at least on control signal to the engine for selecting the speed at which the engine is to operate. The system preferably includes a first electronic controller that provides transmission control signals required to command the powershift transmission to shift to and operate in any particular one of its forward gears, and a second electronic controller that provides at least one engine control signal required to command the engine to operate at one of a number of different desired engine speeds and to monitor the actual engine speed. By use of gear ranges which overlap slightly, and a throttle that is infinitely adjustable within a range of engine speeds, any given ground speed within the range of possible vehicle speeds can be achieved and maintained, as long as the engine is operating within its overall power envelope. The system also supports a pseudo-gear mode where the operator interface indicates there are more gears in the transmission than actually exist.
摘要:
A method for controlling an electro-hydraulically operated infinitely variable transmission of a motor vehicle which is driven, in particular, by an internal-combustion engine, provides a control of the infinitely variable transmission according to several characteristic control curves. The characteristic control curves are selected corresponding to a driving activity which evaluates the driver's driving style or his action with respect to the control of the motor vehicle caused by a traffic situation. The characteristic control curves cover, at least in steps, the range between a characteristic control curve permitting the consumption-optimized operation of the motor vehicle and a characteristic control curve which permits the power-optimizing operation of the motor vehicle.
摘要:
A control system for a motor vehicle provided with a continuously variable transmission. The transmission has a transmission ratio control valve having ports and a spool for controlling the transmission ratio. A throttle position sensor is provided for detecting the load on an engine and for deciding the transmission ratio in accordance with the load. Abnormality of the throttle position sensor is detected by comparing a first load signal immediately after starting of the engine with a subsequent load signal. When difference between the first load signal and the subsequent load signal is smaller than a predetermined value, a fail-safe signal is produced for maintaining the transmission ratio at a moderate value.
摘要:
A control system for a continuously variable transmission has a line pressure control valve having ports and a spool for controlling the line pressure of oil supplied to a cylinder of a driven pulley. The pressure of the oil supplied to control the spool is controlled by an on-off control valve in accordance with engine operating conditions to control the line pressure. The duty ratio of pulses for operating the on-off control valve is obtained by positioning a desired line pressure between the lowest line pressure and the highest line pressure corresponding to duty ratios of 100% and 0%, respectively.
摘要:
A hydraulic control apparatus for controlling a hydraulically-operated power transmitting system for an automotive vehicle, the transmitting system having a continuously variable transmission and an auxiliary transmission coupled to an output side of the continuously variable transmission. The controlling apparatus comprises a first pressure generator for generating a first line pressure used to operate the continuously variable transmission, and a second pressure generator for generating a second line pressure used to operate a frictional coupling assembly incorporated in the auxiliary transmission.
摘要:
A system for an infinitely variable belt-drive transmission for an engine comprises a primary pulley having a hydraulically shiftable disc, a secondary pulley having a hydraulically shiftable disc, a belt engaged with both pulleys, and a hydraulic circuit. A transmission ratio control valve having a spool is provided to be responsive to engine speed for controlling the oil and for shifting the disc of the primary pulley to change the transmission ratio. Pitot pressure dependent of the engine speed is applied to the spool to shift it against a spring, the force of which is determined by the depression of an accelerator pedal. The load on the spring is increased to provide a downshifting operation of the transmission, when the large transmission ratio range is selected.
摘要:
A control system for a motor vehicle provided with a continuously variable transmission and with an electromagnetic clutch for transmitting torque of an engine to the transmission. The transmission has a line pressure control valve having ports and a spool, a hydraulic circuit for supplying oil to the line pressure control valve so as to shift the spool to control the line pressure. When the clutch is slipping at the start of the vehicle, the line pressure control valve is controlled in accordance with a clutch transmitting torque. When the clutch is engaged, the control valve is controlled in accordance with an engine torque.