Abstract: A shift manipulating apparatus for an automatic transmission is disclosed that transmits manipulating force from a shift lever to a manual valve to position the spool of a manual valve at identical places in ranges P and N. The apparatus comprises a shift lever to receive shift range selection manipulating force of a driver; a manual valve to control oil pressure of the automatic transmission; and a linkage unit for connecting the shift lever and the spool of the manual valve to enable the spool to identically form an interconnection state of ports according to pivot of the shift lever in ranges P and N.

Abstract: This invention provides a hydraulic control system for controlling a power train including four clutches and two brakes, wherein a first pressure controlled by a first solenoid valve is selectively supplied to two clutches of the power train under control of a first switch valve, a second pressure controlled by a second control valve is selectively supplied to another clutch and a first brake of the power train under control of a second switch valve, hydraulic pressure from a port of a manual valve is supplied to yet another clutch via a control valve, hydraulic pressure from another port of the manual valve is supplied to a second brake via another control valve, and the two control valves are controlled by a third solenoid valve.

Abstract: Disclosed is a hydraulic control system for controlling an automatic transmission comprising a first clutch for transmitting power through a one-way clutch in first, second and third speeds; a fourth clutch for discontinuing an operation of the one-way clutch and which acts as an engine brake; a second brake operating in second and fourth speeds; a second clutch for transmitting power in third and fourth speeds; a first brake for discontinuing the operation of the one-way clutch in the first speed and acting as an engine brake, and operating in low L and reverse R ranges; and a third clutch for operating in the reverse R range, wherein hydraulic pressure controlled by a first solenoid valve is supplied and exhausted through operation of a switch valve to the second clutch and the first brake, the second brake is directly controlled by hydraulic pressure controlled by a second solenoid valve, and the fourth clutch is directly controlled by hydraulic pressure controlled by a third solenoid valve.

Abstract: Disclosed is a hydraulic control system for an automatic transmission that controls a powertrain, which includes a first friction element for use as an engine brake for discontinuing operation of a one-way clutch in the transmission and a second friction element operating only when the first friction element is disengaged. The hydraulic control system comprises a manual valve including a forward range port for exhausting hydraulic pressure when driving in a forward range, and an L range port for exhausting hydraulic pressure for low speed control; and a switch valve controlled by engine brake signal pressure, solenoid pressure, and forward range pressure supplied from the forward range port, the switch valve selectively supplying control pressure to the first friction element and the second friction element.

Abstract: A line pressure regulating system for an automatic transmission comprises a regulator valve that regulates a line pressure by being provided with a hydraulic pressure from an oil pump, wherein the regulator valve is controlled such that a resultant force of a variable control pressure and an elastic member makes an equilibrium with a resultant force of the line pressure and a range pressure that is provided in all ranges except the R range.

Abstract: A hydraulic control system for an automatic transmission includes a first clutch acting as an input element at first, second, and third forward speed ranges, a second clutch acting as the input element at third and fourth forward speed ranges, a third clutch acting as the input element at an R range, a fourth clutch operating at P, R, N, and L range for performing an engine brake function by stopping a one-way clutch at the first, second, and third forward speed ranges, a first brake acting as a response element at the P, R, N, and L ranges, a second brake acting as a response element at second and fourth forward speed ranges, a first switch valve for distributing hydraulic pressure controlled by a first solenoid valve to a damper clutch in a torque converter and to clutch control valves for the first clutch, and a second switch valve for distributing hydraulic pressure controlled by a second solenoid valve to the second clutch and the first brake.

Abstract: A line pressure control system of an automatic transmission includes a hydraulic pump for generating hydraulic pressure, a regulator valve for adjusting the pressure from the hydraulic pump to a predetermined level, a torque converter control valve for adjusting a partial pressure from the regulator valve, a damper clutch valve receiving the adjusted pressure from the torque converter control valve for feeding the pressure to a damper clutch, a damper clutch solenoid valve for controlling the damper clutch valve, a reducing valve for reducing a partial pressure from the regulator valve and then supplying the reduced pressure to the damper clutch control valve, wherein the regulator valve includes a valve body, first and second valve spools coaxially inserted into the valve body, a sleeve encapsulating the second valve spool, and a coil spring interposed between the first and the second valve spools.

Abstract: A manual valve of a hydraulic pressure control system for an automatic transmission includes a valve body and a valve spool slidably inserted into the valve body, wherein the valve body is provided with a first port communicated with a regulator valve via a pressure line, a second port connected to a first pressure control valve and a second fail safe valve so as to supply hydraulic pressure thereto at range “P”, a third port connected to the regulator valve, an N-R control valve, and first and second switch valves so as to supply the hydraulic pressure from the first port thereto at range “R”, a fourth port connected to second and third pressure control valves and the first and second switch valves so as to supply the hydraulic pressure from the first valve thereto at ranges “2”, “3”, and “D”, and a fifth port connected to the first switch valve so as to supply the hydraulic pressure from the first port thereto at range “L”.

Abstract: A hydraulic control system for an automotive automatic transmissions includes a pressure regulator for regulating hydraulic pressure, a pressure reducer having a reducing valve for reducing hydraulic pressure, a shift controller having a manual valve cooperating with a shift selector lever and connected to a plurality of range pressure lines, a pressure controller comprising first, second and third solenoid valves for controlling control pressure reduced by the reducing valve, and first, second and third pressure control valves for controlling hydraulic pressure supplied from the manual valve, the first, second and third pressure control valves being independently controlled by control pressure supplied from the first, second and third solenoid valves, respectively, a switching controller comprising a first switch valve for supplying hydraulic pressure from the first pressure control valve to one of first and second switching lines and a second switch valve for supplying hydraulic pressure from the third pres