摘要:
A hydraulic control system according to the present invention which features in providing an orifice fluidly disposed in a passage that allows fluid supply of hydraulic fluid pressure to a clutch in selecting a forward drive range from a neutral range and in shifting between speed ratios involving engagement of the clutch in the forward drive range, and an orifice control valve having means for providing a one-way flow bypass passage bypassing the orifice in selecting the forward drive range from the neutral range and selecting the neutral range from the forward drive range, and providing a restricted flow bypass passage bypassing the orifice in shifting between speed ratios involving engagement of the clutch. The one-way flow bypass passage prevents fluid flow therethrough toward the clutch.
摘要:
A shift valve for an automatic transmission wherein governor pressure acts on a spool in such a direction as to compress a first spring, and throttle representative pressure acts on a plug in such a direction as to compress the first spring. The shift control valve further comprises a second spring arranged to act on the spool in the same direction as the direction in which the governor pressure acts on the spool.
摘要:
A hydraulic control system comprises a control valve with a solenoid valve operatively connected thereto to modulate the characteristic of hydraulic fluid pressure supplied to a friction element that is to be engaged during a shift in speed ratio. The current supplied to the solenoid is varied in ON/OFF manner in accordance with a duty factor computed by a control unit. The control unit includes a memory storing a map containing various duty factors corresponding to various kinds of shifts and determines an adequate duty factor for a shift which is to take place in the transmission. The characteristic of the hydraulic fluid pressure is modulated during a time period variable with vehicle speed and engine torque which are measured by sensors associated with the control unit.
摘要:
In order to stabilize the line pressure developed by a line pressure regulator valve and simultaneously control the operation of a variable capacity pump in a manner that the latter exhibits the desired degree of response to changes in the line pressure, a flow restriction is defined in the bore of the valve itself. This flow restriction is defined between the wall of the bore in which the spool is disposed and a portion of the spool which extends between two adjacent lands and which has a diameter which is slightly smaller than that of the bore.
摘要:
An automatic transaxle comprises a rotary motion transmitting unit which transmits a rotary motion between two parallel shafts including an input shaft in driving connection with a turbine of a hydrodynamic unit, i.e., a torque converter. The rotary motion transmitting unit includes a driver sprocket, a follower sprocket, and a chain in driving connection between the sprockets. The pump has a pump housing fixed to a stationary support plate. The driver and follower sprockets are rotatably supported at this stationary support plate. A reaction shaft in driving connection with an inner race of a one-way clutch of a stator of the torque converter extends through the stationary support plate and rotatably supports the driver sprocket. The reaction shaft is hollow to allow the input shaft to extend therethrough. The input shaft is drivingly connected with the driver sprocket. The pump has a pump shaft including a sleeve portion coaxially arranged around and with the reaction shaft and a radial extension fixed to the impeller. Accordingly, the driver is spaced further away from the torque converter in a direction along the input shaft than the pump.
摘要:
A shift control system for an automatic transmission is disclosed, which comprises, in the first embodiment for example, an orifice bypass valve including a spool, a spring and a pilot port. The spool is movable between an interrupting position where a first hydraulic passage is interrupted from a third hydraulic passage, and a connecting position where a first passage is connected with a third passage, and it is pressed to the interrupting position by the spring. The pilot port induces a force by which the spool is pressed in the direction opposite to a force of the spring when the hydraulic fluid is supplied, and it is connected with a fourth hydraulic passage for receiving the hydraulic fluid for operating an overrunning clutch.
摘要:
A shift valve which controls the shifting of the transmission between the top speed and the next lower one is arranged to have a port which is communicable with an overrunning clutch viz a relatively short conduit arrangement. The port is arranged to be constantly supplied with line pressure while the manual valve is set in any of the forward drive ranges, and to be communicated with the conduit when the shift valve is supplied with a top speed inhibit signal and induced to assume its downshift position.
摘要:
A shift control system for an automatic transmission comprises a shift valve for an auxiliary gear train and an accumulator for low gear train. The shift valve includes a spool which is movable between a first position where the hydraulic fluid is supplied to a first passage and hydraulic fluid is discharged from a second passage, and a second position where the hydraulic fluid is supplied to the second passage and hydraulic fluid is discharged from the first passage. The accumulator includes a working pressure chamber and a back pressure chamber which is connected with a third passage or engine brake passage.
摘要:
In an automatic transmission, a governor shaft is arranged so that a center axis of a governor shaft is interposed between a center axis of an idler shaft and a center axis of a final drive gear. In one embodiment, the center axis of the governor shaft is further disposed between a center axis of an output gear and the center axis of the final drive gear, and a governor valve is disposed above a drive shaft joint. In another embodiment, the governor valve is disposed below the drive shaft joint.
摘要:
A second spool valve element which is engageable with the one which actually controls discharging of hydraulic fluid in a manner which controls the level of the line pressure, has first and second lands, the first and second lands defining a pressure differential area which can be exposed to a first control pressure indicative of the transmission being shifted out of D range into a lower one, in a manner to bias the second valve toward the first spool valve element; a chamber is defined in the valve bore to which the engageable ends of the first and second spools are exposed and which is supplied with a second control pressure indicative of the torque being applied to the tranmission, the second control pressure producing a bias which tends to move the the first and second spool valve elements apart.