摘要:
A hydraulic control apparatus for controlling a continuously variable transmission of a motor vehicle, which transmission includes a first and a second shaft, a pair of variable-diameter pulleys provided on the first and second shafts, respectively, a transmission belt connecting the pulleys, and a pair of hydraulic actuators one of which receives a belt tensioning pressure for controlling a tension of the belt. The hydraulic control apparatus includes a reversal detecting device for determining whether a rotating direction of the pulleys has been reversed or not, and a pressure increasing device for temporarily increasing the belt tensioning pressure when the reversal detecting device detects reversal of the rotating direction of the pulleys.
摘要:
A hydraulic control apparatus for controlling a vehicle power transmitting system including a belt-and-pulley type continuously variable transmission and a torque converter provided with a lock-up clutch. The transmission includes a pair of hydraulic actuators one of which receives a belt tensioning pressure for controlling a tension of a transmission belt. The hydraulic control apparatus includes a lock-up clutch control valve which is selectively placed in an engaging and a releasing position for engaging and releasing the lock-up clutch, respectively, a slip control valve for controlling an amount of slipping of the lock-up clutch until the clutch is fully engaged, a pressure control device for raising the belt tensioning pressure so as to increase the tension of the transmission belt; and a pilot-pressure generating device for applying a pilot pressure simultaneously to the slip control valve and the pressure control means, so that the belt tensioning pressure is raised while the slip control valve controls the amount of slipping of the lock-up clutch.
摘要:
A hydraulic control apparatus for controlling a belt-and-pulley type continuously variable transmission of a motor vehicle having an engine, which transmission includes a pair of hydraulic actuators one of which receives a belt tensioning pressure for controlling a tension of a transmission belt. The hydraulic control apparatus includes an engine-output detecting valve for generating an engine output pressure indicative of a currently required output of the engine, a solenoid-operated valve for regulating a modified engine output pressure based on the engine output pressure generated by the engine-output detecting valve, and a pressure regulating valve for regulating the belt tensioning pressure based on at least the modified output pressure. The modified engine output pressure is obtained so that the belt tensioning pressure is controlled to an optimum level.
摘要:
A hydraulic control apparatus for a vehicle power transmitting system having a continuously variable transmission having a first and a second shaft, a pair of variable-diameter pulleys provided on the shafts, a belt connecting the pulleys, and two hydraulic actuators for changing diameters of the pulleys. The apparatus includes a directional control valve for supplying a fluid from a pressure line to one of the two actuators while discharging the fluid from the other actuator, a first fluid passage connected to the directional control valve, for primarily supplying the fluid from the pressure line to a driving side actuator of the two actuators which is provided on a driving one of the first and second shafts, a second fluid passage connected to the directional control valve, for primarily supplying the fluid from the pressure line to a driven side actuator of the hydraulic actuators, and a flow restrictor for restricting a flow of the fluid through the first fluid passage so that a fluid flow resistance of the first fluid passage is higher than a fluid flow resistance of the second fluid passage.
摘要:
A hydraulic control apparatus for a power transmitting system for an automotive vehicle having a continuously variable transmission which has a first and a second shaft, a pair of variable-diameter pulleys provided on the first and second shafts, a belt connecting the pulleys, and a pair of hydraulic actuators for changing diameters of the pulleys, wherein a tension of the belt is controlled by regulating an actuating pressure in a driven side actuator of the hydraulic actuators which is provided on a driven one of the two shafts. The apparatus includes a pressure regulating valve which has a valve spool for regulating the actuating pressure in the driven side actuator, and a pressure-reducing chamber for receiving a pressure-reducing pilot pressure for biasing the spool for reducing the actuating pressure. The apparatus further includes a pilot pressure generator for generating the pressure-reducing pilot pressure to be applied to the pressure-reducing chamber, when the detected vehicle running speed exceeds a predetermined value.
摘要:
A hydraulic control apparatus for a power transmitting system including a continuously variable transmission, a reversing device, and an auxiliary transmission, which apparatus includes: a solenoid valve for generating a pilot pressure for selectively placing the auxiliary transmission in high- and low-gear positions; high-gear and low-gear control valves normally operable based on the pilot pressure, to control high- and low-gear coupling devices of the auxiliary transmission to establish the high- and low-gear positions. The low-gear control valve is operated to engage the low-gear coupling device, when the low-gear control valve receives a pressure to be applied to the reversing device for forward run of the vehicle. The high-gear control valve may be operated to release the high-gear coupling device, when a thrust based on a pressure applied to the low-gear coupling device exceeds a predetermined value. The hydraulic control apparatus may further include a device for increasing a torque capacity of the high-gear coupling device during an engaging action thereof when a shift lever is operated to a reverse-drive position for reverse run of the vehicle.
摘要:
A control apparatus for a vehicle includes a power transmitting system between an engine and wheels. The transmitting system has a continuously variable transmission (CVT) and a motor-generator actuated in one of a regenerating operation mode and an assisting operation mode. The motor-generator serves as a generator in a regenerating operation mode and as a motor in an assisting operation mode. The apparatus includes an electric control unit (ECU) that determines a shift of engine speed, computes the total amount of torque of the engine, the CVT and the motor-generator and selects one of the operation modes and actuates the motor-generator base on the selected operation mode to corrects the engine speed.
摘要:
A hydraulic control apparatus for a vehicle continuously variable transmission including a pressure regulating valve having a valve spool which operates depending upon a determined current speed ratio of the transmission and a currently detected required output of the vehicle engine, to generate a controlled belt tensioning pressure for controlling the tension of a transmission belt at a required minimum level. The apparatus further includes a device responsive to an electric signal, for generating a pilot pressure to be applied to the valve, and an electronic control device for calculating a basic output pressure of the valve, based on the current speed ratio and the currently required output, according to a stored predetermined relationship among these two parameters and the basic output pressure, to determine the electric signal so that the belt tensioning pressure coincides with the optimum value.
摘要:
In a seal device for a hydraulic circuit, in which an oil passage that supplies hydraulic oil to or discharges the hydraulic oil from a hydraulic actuator operated by hydraulic pressure is formed over at least two members that relatively move, and a seal member that seals a gap between the two members in a liquid-tight manner is disposed in an interior of a groove section that is formed in at least either one of the two members, a communication section that allows the groove section to communicate with any portion of the oil passage such that the hydraulic oil in the interior of the groove section moves along with supply of the hydraulic oil to or discharge of the hydraulic oil from the hydraulic actuator is formed.
摘要:
A hydraulic control unit configured to improve energy efficiency is provided. The hydraulic control unit is comprised of: a feeding passage that delivers fluid from at least any of an oil pump and an accumulator storing hydraulic pressure to an actuator; a draining passage that discharge the fluid from the actuator to a drain spot; and a discharging means that is configured to selectively discharge the fluid from the actuator to the accumulator through the feeding passage, if the fluid has to be discharged from the actuator and a pressure of the accumulator is lower than that of the actuator.