摘要:
In a vehicular belt-driven continuously variable transmission, belt squeezing force is inhibited from becoming excessive and a safety factor, with respect to belt slip, of belt squeezing force applied to a transmission belt (48) is reduced to a value that is less than or equal to 1.5 by reducing a pressure receiving area (SOUT) of an output side hydraulic cylinder (46c). As a result, a centrifugal hydraulic pressure canceller chamber on a secondary pulley side (46) can be eliminated thus simplifying the structure of the vehicular belt-driven continuously variable transmission, while belt squeezing force can be appropriately controlled.
摘要:
A hydraulic control system for a vehicular drive system including a hydraulically operated belt-and-pulley type continuously variable transmission and a hydraulically operated frictional coupling device engaged for running of a vehicle, the hydraulic control system including: a first solenoid valve for regulating a belt-tensioning hydraulic pressure for tensioning a belt of the transmission, a second solenoid valve for regulating a transient coupling hydraulic pressure to be applied to the frictional coupling device in the process of an engaging action, a line-pressure regulating valve for regulating a line pressure used for hydraulically operated devices of the mechanism, and a hydraulic-circuit switching device operable to apply a control pressure of the second solenoid-operated valve to the line-pressure regulating valve after the frictional coupling device has been placed in a fully engaged state, and to apply a first control pressure of the first solenoid-operated valve to the line-pressure regulating valve while the frictional coupling device is in the process of the engaging action.
摘要:
In a vehicular belt-driven continuously variable transmission, belt squeezing force is inhibited from becoming excessive and a safety factor, with respect to belt slip, of belt squeezing force applied to a transmission belt (48) is reduced to a value that is less than or equal to 1.5 by reducing a pressure receiving area (SOUT) of an output side hydraulic cylinder (46c). As a result, a centrifugal hydraulic pressure canceller chamber on a secondary pulley side (46) can be eliminated thus simplifying the structure of the vehicular belt-driven continuously variable transmission, while belt squeezing force can be appropriately controlled.
摘要:
A hydraulic control system for a vehicular drive system including a hydraulically operated belt-and-pulley type continuously variable transmission and a hydraulically operated frictional coupling device engaged for running of a vehicle, the hydraulic control system including: a first solenoid valve for regulating a belt-tensioning hydraulic pressure for tensioning a belt of the transmission, a second solenoid valve for regulating a transient coupling hydraulic pressure to be applied to the frictional coupling device in the process of an engaging action, a line-pressure regulating valve for regulating a line pressure used for hydraulically operated devices of the mechanism, and a hydraulic-circuit switching device operable to apply a control pressure of the second solenoid-operated valve to the line-pressure regulating valve after the frictional coupling device has been placed in a fully engaged state, and to apply a first control pressure of the first solenoid-operated valve to the line-pressure regulating valve while the frictional coupling device is in the process of the engaging action.
摘要:
In one embodiment, an oil pressure control apparatus includes a belt-driven continuously variable transmission, a lockup clutch provided in a torque converter, a primary regulator valve that regulates a line oil pressure that becomes a source pressure of oil pressure of various parts, and a lockup control valve that performs switching when controlling engagement/release of the lockup clutch. Control of the primary regulator valve and control of the lockup control valve are performed with a single linear solenoid valve. In this case, control of the primary regulator valve and control of the lockup control valve are performed in different ranges.
摘要:
In one embodiment, an oil pressure control apparatus includes a belt-driven continuously variable transmission, a lockup clutch provided in a torque converter, a primary regulator valve that regulates a line oil pressure that becomes a source pressure of oil pressure of various parts, and a lockup control valve that performs switching when controlling engagement/release of the lockup clutch. Control of the primary regulator valve and control of the lockup control valve are performed with a single linear solenoid valve. In this case, control of the primary regulator valve and control of the lockup control valve are performed in different ranges.
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 circuit cleaning apparatus has a hydraulic circuit that includes an oil pump, an oil passage to which the oil pressure ejected from the oil pump is supplied, and a pressure regulator device connected to the oil passage for regulating the oil pressure in the oil passage. The apparatus cleans the hydraulic circuit by using a cleaning liquid. A discharge oil passage is connected to a discharge port of the pressure regulator device, so that the cleaning liquid is discharged out of the hydraulic circuit via the discharge oil passage.
摘要:
A hydraulic control apparatus for a vehicle power transmitting system having a fluid coupling equipped with a lock-up clutch, and a transmission to which power is transmitted from an engine of the vehicle through the fluid coupling. The fluid coupling has an engaging chamber and a releasing chamber for engaging and releasing the lock-up clutch. The apparatus includes a discharge passage communicating with the engaging chamber, for normally draining the engaging chamber to a drain, to thereby normally release the lock-up clutch, and a rapid release valve connected to the discharge passage. The rapid release valve operates to by-pass the discharge passage to the drain therethrough, for thereby rapidly draining the engaging chamber to rapidly release the lock-up clutch. A lock-up pressure regulating valve is provided for regulating a lock-up clutch pressure applied to the fluid coupling, normally to a first value, and upon operation of the rapid release valve, to a second value higher than the first value.
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.