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 of a vehicle according to the present invention comprises a valve body provided with a line pressure receiving port, a P/N range port for supplying hydraulic pressure in more than one range of parking range P and neutral range N, a plurality of hydraulic pressure supplying ports and a plurality of exhaust ports; and a valve spool slidably inserted into the valve body and having a plurality of valve lands, a first valve land of said plurality of valve lands having a exhaust groove depressed toward a neighboring land, wherein: each width of the line pressure receiving port and the P/N range port is smaller than each diameter of said plurality of valve lands, whereby a tight seal is maintained when each of the line pressure receiving port and the P/N range port is blocked by said plurality of valve lands; and each width of the plurality of hydraulic pressure supplying ports is greater than each diameter of said plurality of valv

Abstract: A hydraulic control system includes a pressure/damper clutch controller, a pressure reducer, and a shift controller. The shift controller includes a manual valve indexed with a driver-controlled select lever to supply hydraulic pressure to the hydraulic pressure controller, the hydraulic pressure distributor, and the friction elements.

Abstract: A manual 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: 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: 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: A manual valve of a hydraulic pressure control system for an automatic transmission of a vehicle according to the present invention comprises a valve body provided with a line pressure receiving port, a P/N range port for supplying hydraulic pressure in more than one range of parking range P and neutral range N, a plurality of hydraulic pressure supplying ports and a plurality of exhaust ports; and a valve spool slidably inserted into the valve body and having a plurality of valve lands, a first valve land of said plurality of valve lands having a exhaust groove depressed toward a neighboring land, wherein:

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 hydraulic pressure distributor includes a low control valve, an N-R control valve, a line pressure control switch valve, a first fail-safe valve controlled by control pressure supplied from the low control valve and from the second pressure control valve, the first fail-safe valve undergoing port conversion to supply hydraulic pressure supplied from the third pressure control valve to the second clutch in the third and fourth speeds of the drive D range, and hydraulic pressure supplied from the third pressure control valve to the first brake in the low L range, and a second fail-safe valve controlled by reverse pressure, hydraulic pressure supplied to a fourth clutch, and hydraulic pressure supplied to the third clutch, the second fail-safe valve supplying hydraulic pressure supplied from the second pressure control valve to the second brake in the second and fourth speeds of the drive D range, and an engine brake control switch valve for supplying D-range pressure to the fourth clutch in the first and thir

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

Abstract: A hydraulic control system includes a pressure regulator for controlling hydraulic pressure generated by an oil pump, the pressure regulator being realized through a pressure regulator valve; a pressure reducer realized through a reducing valve for maintaining pressure at a level lower than line pressure; a damper clutch controller for operating a damper clutch of a torque converter; a shift controller for forming shift modes, the shift controller being realized through a manual valve indexed with a select lever operated by a user; a hydraulic pressure controller for providing shift quality and shift responsiveness to enable smooth shifting; and a hydraulic pressure distributor for supplying suitable hydraulic pressures to first, second, third, fourth and fifth friction elements operating as input and reaction elements in each shift stage, the hydraulic pressure distributor being realized through a plurality of spool valves.

Abstract: A hydraulic control system for an automatic transmission including a plurality of friction elements associated with respective transmission speeds. The hydraulic control system includes a hydraulic fluid source, a line pressure controller, a reducing pressure controller, a range controller, a shift controller, a hydraulic pressure controller, wherein the hydraulic pressure distributor includes a 3-4 shift valve, a 2-3/4-3 shift valve, a 1-2 shift valve, a control switch valve for selectively supplying/exhausting hydraulic pressure from the shift controller to at least one of the friction elements corresponding to the respective transmission speeds to control operating timing of each corresponding friction element and supplying the hydraulic pressure from the shift controller to the line pressure controller to reduce line pressure at a high speed state; and a solenoid valve for controlling the control switch valve in accordance with a control signal of the transmission control unit.

Abstract: Disclosed is a hydraulic control system for an automatic transmission including a plurality of friction elements associated with respective transmission speeds. The hydraulic control system includes a hydraulic fluid source, a line pressure controller, a reducing pressure controller, a range controller, a shift controller, a hydraulic pressure controller, and a hydraulic pressure distributor.

Abstract: A manual shift control device of a transmission control system for an automotive automatic transmission. A solenoid feed valve feeds line pressure passing through a pressure regulator valve to first, second and third solenoid valves. A torque control regulator valve changes drive pressure into torque pressure. A control switch valve alternatively feeds torque pressure to first and second torque pressure passages. An N-D control valve sequentially feeds torque pressure and drive pressure to a second friction member, which is applied at an initial shift operation together with a first friction member, to thereby alleviate shift shock from neutral range "N" to drive range "D". A first-to-second speed shift valve feeds part of the torque pressure and part of the drive pressure to a third friction member during a shift operation from the first speed to the second speed.

Abstract: A pressure control valve of a hydraulic control system of automatic transmissions has reducing pressure PR supplied from a reducing valve by duty control of a pressure control solenoid valve controlled by a transmission control unit thereby changing line pressure PL supplied from a manual valve into the control pressure and supplying the control pressure to the friction element. The valve comprises a valve spool operated by the duty-controlled reducing pressure, a valve body in which the valve spool linearly moves, and a feedback line which communicates the control pressure with one side of the valve body thereby reducing the deviation of the control pressure.

Abstract: An electronic and hydraulic system of a five speed automatic transmission adapted to establish five forward and one reverse gear ratios by way of effecting selective engagement and disengagement of friction elements comprises an oil pump for producing a pressurized working fluid, a manual selector valve manually operated for distributing the working fluid to forward and reverse fluid lines, first to fourth shift valves for directing the working fluid to one of the friction elements, first to fourth solenoid valves associated with the first to fourth shift valves, respectively, for controlling positions of the shift valves in correspondence to a vehicle speed and a throttle opening degree, second to fourth speed valves each position-controlled by the first to third shift valves to change flow path of the working fluid and an overdrive unit valve position-controlled by the fourth shift valve.