摘要:
A control system for a motor vehicle provided with a continuously variable transmission and a clutch for transmitting power of an engine to the 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 a desired transmission ratio in accordance with the load. The clutch is automatically disengaged at low vehicle speed. When an accelerator pedal is depressed in order to re-accelerate the vehicle, the desired transmission ratio is increased to increase the speed of a drive pulley of the transmission so that the drive pulley speed equals the speed of the engine.
摘要:
A control system for a motor vehicle provided with a continuously variable transmission which has a transmission ratio control valve having a spool for controlling the transmission ratio. During the acceleration of the vehicle, the transmission ratio is quickly reduced in a low vehicle speed range, whereby speed of an engine is kept low compared with a high vehicle speed range.
摘要:
A system for controlling an infinitely variable transmission is provided with a vehicle speed sensor for sensing vehicle speed and for producing a signal when the vehicle speed exceeds a predetermined value, a neutral range sensor of the transmission, a drive range sensor, and an accelerator pedal release sensor. The system further has an actuator for cutting off fuel. When the vehicle coasts under conditions of the drive range, accelerator pedal release, and at a higher vehicle speed than the predetermined value, fuel is cut off. When the neutral range is selected under the fuel cut off state, the clutch is engaged with a delay.
摘要:
A system for controlling an electromagnetic clutch has a reference valve generator which produces clutch-engaging and clutch-disengaging engine speed signals in a low vehicle speed range. Engine speed is compared with the engine speed signals by a comparator. The clutch is engaged at a higher engine speed than a clutch disengaging speed and disengaged at a lower engine speed than a clutch engaging speed in accordance with the result of the comparison.
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 pulley device to change the transmission ratio. The line pressure control valve has chambers. When the transmission ratio reaches a maximum value after disengagement of a clutch, a line pressure reducing signal generates. The signal is applied to the line pressure control valve to shift the spool thereof, so that the line pressure is reduced to a minimum value. By controlling the pressure of oil supplied to the chambers in accordance with a desired line pressure, the spool is shifted, so that the line pressure is controlled.
摘要:
A control system for an infinitely variable belt-drive transmission 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 having a pump for supplying oil. A transmission ratio control valve 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, and a pressure regulator valve is provided to respond to the transmission ratio for increasing the pressure of the oil with an increase of the transmission ratio. A pickup is provided to produce pulses dependent on engine speed, and a electric circuit is responsive to the pulses for producing pulses. An electromagnetic valve is provided to respond to the pulses for draining the oil applied to the transmission ratio control valve thereby controlling the valve so as to provide at least two transmission ratio characteristics.
摘要:
A belt drive continuously variable transmission of a four-wheel motor vehicle has a transmission ratio control valve which is operated in accordance with driven pulley speed. An analogous driven-pulley speed is calculated based on an analogous vehicle speed approximate to actual vehicle speed. In response to the analogous driven-pulley speed, the analogous driven pulley speed is used for operating the transmission ratio control valve instead of the driven pulley speed.
摘要:
A control system for a continuously variable transmission having a drive pulley with a hydraulically shiftable disc and a hydraulic cylinder for operating the disc, a driven pulley with a hydraulically shiftable disc and a hydraulic cylinder, and a pressure regulator valve for regulating pressure of oil supplied to the hydraulic cylinders. The pressure regulator valve has a pressure level changing port to increase the pressure of oil supplied to the cylinders. A solenoid operated valve is provided for supplying the oil to the pressure level changing port or for draining the port. When wheels of a vehicle spin, the solenoid operated valve is energized to supply the oil to the port, thereby increasing the pressure of the oil.
摘要:
A belt is formed by a plurality of metal elements which are assembled by a pair of endless carriers engaging with the elements at both lateral sides thereof. Each element has a plurality of protrusions at the front side thereof so as to engage with the rear side of an adjacent element. The protrusions are provided for appropriately deviating the belt at a tight side.
摘要:
A control system for a motor vehicle provided with a continuously variable transmission which has a transmission ratio control valve having a spool for controlling the transmission ratio. During the deceleration of the vehicle by closing a throttle valve of the engine, the transmission ratio is upshifted when engine speed does not greatly fluctuate, so that engine speed is reduced further.