Abstract: A lock-up clutch control system for automatic transmissions having a lock-up control valve supplied with said line and solenoid pressures in opposite fluid chambers for engaging and releasing a lock-up clutch, the lock-up control valve being constructed to satisfy the following conditions (5) and (7) ##EQU1## where A.sub.1 is a land area of a spool for receiving the line pressure, A.sub.2 is a land area for receiving the solenoid pressure, F is the force of a biasing spring, PL is the line pressure, and Ps is the solenoid pressure.

Abstract: In a hydraulic control system for automatic transmissions of motor vehicles, a lock-up control circuit for controlling a direct-coupling clutch of a torque converter, the lock-up control circuit comprising: a lock-up control valve having a spring-biased valve spool and operated by solenoid pressure applied to a spring-loaded end of the valve spool and oil pressure applied to the other end of the spool upon shift to a predetermined gear position and in higher gear positions, connecting an oil pressure source with either a clutch engaging conduit or a clutch releasing conduit of the direct-coupling clutch of the torque converter; with ON-OFF operation of solenoid valve; and a solenoid valve provided in an oil conduit communicating with the spring-loaded end of the spool and adapted to produce the solenoid pressure in a gear position lower than said predetermined lock-up gear position.

Abstract: A continuously-variable speed transmission for motor vehicles, which transmission comprises an input variable pitch pulley arranged on the input shaft of the transmission, an output variable pitch pulley arranged on the output shaft of the transmission, an endless belt interconnecting the input and the output variable pitch pulleys, a forward-drive planetary gear mechanism disposed on one axial side of the variable pitch pulley arranged either on said input shaft or on said output shaft, and a reverse-drive planetary gear mechanism disposed on the other axial side of said variable pitch pulley.

Abstract: A belt drive continuously-variable speed automatic transmission for motor vehicles, comprises a torque converter, forward/reverse rotation changeover mechanism, a belt drive continuously-variable speed transmission means and a differential gear disposed in a single housing in an integrated unit.The belt drive continuously-variable speed transmission means comprises a primary variable-pitch pulley mounted on the intermediate shaft, a secondary variable-pitch pulley mounted on an output shaft rotatably supported on the housing in parallel to the intermediate shaft and an endless belt interconnecting the primary and the secondary variable-pitch pulleys.

Abstract: A power transmission endless belt formed by connecting in succession a plurality of metal blocks each having at least a through hole or a recess to an endless connecting band formed by connecting a plurality of link plates with pins. The endless connecting band is inserted through the through hole or the recess of the metal block and the metal block is connected to the link plates with a pin or is retained between two pins.

Abstract: An automatic transmission provided with a combination of a belt drive continuously-variable speed transmission mechanism and a hydraulic control circuit. The belt drive continuously-variable speed transmission mechanism has an input variable-pitch pulley assembly and an output variable-pitch pulley assembly. The hydraulic control circuit includes a regulator valve, a throttle pressure valve, a reduction ratio detecting valve, a reduction ratio control valve and a reduction ratio control mechanism. The reduction ratio control valve has an axially slidable spool and two pressure chambers formed in the valve body thereof at both axial ends of the spool respectively. The reduction ratio control mechanism includes conduits for conducting the working fluid of a throttle pressure to the pressure chambers of the reduction ratio control valve and two solenoid valves adapted to drain the corresponding pressure chambers, respectively, when actuated.

Abstract: A stepless or continuously variable automatic transmission for motor vehicles including a first shaft coupled with the output shaft of an engine and rotatably supported by the transmission case, a second shaft disposed parallel with the first shaft and supported by the transmission case rotatably at three support points, and a third shaft disposed parallel with the second shaft and rotatably supported by said transmission case, transmitting power from said first to second shaft by a V-belt type stepless transmission and from the second to third shaft by meshed engagement of an output gear mounted on the second shaft and an input gear mounted on the third shaft, said stepless automatic transmission being characterized in that: the second shaft is divided into an input section mounting an output pulley of said V-belt type stepless transmission and an output section mounting the output gear, one of the input and output sections being rotatably supported at one outer support point and an intermediate support poin

Abstract: A stepless or continuously variable automatic transmission for motor vehicle, including a first shaft coupled with the output shaft of the engine and rotatably supported by the transmission case consisting of a torque converter case accommodating a fluid joint, a transmission case fastened to the torque converter case and accommodating a V-belt type stepless transmission and a center case interposed between the torque converter and transmission cases; a second shaft disposed parallel with the first shaft and supported by the transmission case rotatably at three support points on the torque converter case, transmission case and center case; and a third shaft disposed parallel with the second shaft and rotatably supported by the transmission case, transmitting power from the first to second shaft by the V-belt type stepless transmission and from the second and third shaft by meshed engagement with a helical output gear mounted on the second shaft and a helical input gear mounted on the third shaft, the stepless

Abstract: A front cover affixed to the pump impeller of a torque converter, provided with a flat annular flat annular surface to be engaged with the clutch disk of a direct-coupling clutch formed within the torque converter.The flat annular surface is formed in a flat and annular surface having a hard and compact metallographic structure by rolling a rolling tool made of a extremely hard material on the flat annular surface under a pressure and by thus causing plastic deformation of the flat annular surface. An intermediate part of an arcuate section of a small radius is formed between the periphery of said flat annular surface and a connecting part adjacent to the flat annular surface.

Abstract: A hydraulic centrifugal clutch comprises an input shaft; an output shaft; a hydraulic servomechanism including a fixed cylinder fixed to said input shaft, an axially movable piston mounted on said input shaft and forming a first cylindrical chamber in combination with said fixed cylinder, and a fixed piston fixedly mounted on said input shaft and fitted in a cylindrical flange portion of said movable piston for forming a second cylindrical chamber in combination with said movable piston. A friction clutch mechanism is formed between said output shaft and said fixed cylinder, and a diaphragm spring is disposed within said second cylindrical chamber.

Abstract: In a hydraulic control system for an automatic transmission for vehicles having a pump being driven by the engine of the vehicle for generating a pressure of pressurized fluid in the hydraulic control system, and a pressure regulator valve for regulating the pressure of pressurized fluid supplied from the pump in keeping with an input signal pressure varying in accordance with the cruising condition of the vehicle, a pressure relief valve is provided in the input fluid passage of the regulator valve for relieving the pressure when the input signal pressure exceeds a predetermined level.

Abstract: A hydraulic control system for a four-wheel drive transfer mechanism for vehicles, including an automatic transmission, a transfer mechanism having a two-wheel drive direct-coupling gear (H.sub.2), a four-wheel drive direct-coupling gear (H.sub.4) and a reduced-speed four-wheel drive gear (L.sub.4) and a hydraulic control circuit for controlling the transmission and the transfer mechanism. The transfer mechanism includes a reduction gear mechanism, a first output shaft, a second output shaft connected to the first output shaft by means of a linkage, a four-wheel drive clutch for detachably connecting or disconnecting the first and second output shafts, direct-coupling clutch for connecting or disconnecting the input shaft of the reduction gear mechanism and the first output shaft and a reduced-speed drive brake for shifting the reduction gear mechanism into the reduced-speed range.

Abstract: A sealing and connecting device for cables used in a hydraulic control system of an automatic transmission includes a connecting element to be fixed into a hole formed in a housing in which the hydraulic control system is installed. The connecting element is formed substantially in cylindrical shape and provides plural passages and an internal cylindrical space, wherein a rubber bushing is inserted having the same number of through holes as the number of the above passages. Cables having ends electrically connected to a solenoid valve in the hydraulic control system are inserted through the holes in the rubber bushing, and the free ends of the cable are electrically connected within the above passages to other cables which are electrically connected outside the housing. A synthetic resin filler is poured into the surroundings of the cable connection and into the passages where it sets.

Abstract: The automatic transmission control apparatus includes a single dual sequence valve in the hydraulic control circuit which provides timing control functions for engaging the brakes, engaging the brakes and one-way clutch, and operating the dual pistons operatively associated with the clutch, thereby preventing overheat of the friction engagement elements, improving the shifting of the gears through the speed range, and simplifying the hydraulic control circuit arrangement.

Abstract: An overdrive unit in an automatic transmission having a planetary gear set including a helical gear and a thrust bearing interposed between the sun gear and revolving carrier for supporting any thrust loads produced between the sun gear and the carrier, thereby reducing the amount of any external force to be exerted on the outer race of the one-way clutch and thus improving the durability of the one-way clutch.

Abstract: A torque transfer mechanism includes the output shaft of a power source to be connected to the rear axle, a first intermediate output shaft disposed concentrically with said output shaft, a second intermediate output shaft to be connected to the front axle, a power transmitting means for drivingly connecting said first and second intermediate output shafts, and a frictional coupling means interposed between said output shaft and said first intermediate output shaft. Said frictional coupling means comprises frictional members, a first cylinder, a first piston received in said first cylinder and adapted to apply a pressure to said frictional members, a second cylinder formed in said first piston, and a second piston received in said second cylinder. When the pressurized fluid is supplied only to said second cylinder, a slip between said output shaft and said first intermediate output shaft is allowed during the running of the vehicle along a curve to allow easy running operation of the vehicle.

Abstract: A reduction ratio detecting mechanism for V-belt type continuously variable transmission of this invention comprising a spool disposed with one end thereof projecting from a valve body containing said oil-hydraulic controller of said V-belt type continuously variable transmission and with the axis thereof in parallel with the axis of either one of said input and output pulleys and capable of providing a reduction ratio pressure corresponding to the amount of displacement of said spool, said reduction ratio pressure being applied to said oil-hydraulic controller, wherein the movable flange of said input pulley or said output pulley and said reduction ratio valve are connected by a connecting lever which is engaged, at one end thereof, with said movable flange so as to allow the turning of said movable flange and, at the other end thereof, with the projecting part of said spool, is capable of directly and accurately detecting the reduction ratio between the input and output shafts.

Abstract: In a hydraulic regulator in a V-belt type continuously variable transmission for vehicles, a regulator valve supplied with input hydraulic pressure controls the line pressure as output hydraulic pressure depending on to the throttle opening, the reduction ratio between the input and output shafts of the V-belt type continuously variable transmission and the shift position of a manual valve. As the line pressure is close to the minimum value needed, power loss in the oil pump as well as fuel consumption are reduced.

Abstract: A hydraulic governor pressure generator including a governor body fixedly mounted on a rotational shaft, a governor valve movably mounted in a cavity of the governor body in the radial direction with respect to the rotational shaft according to centrifugal force acting thereon, an input oil passage and an output oil passage provided in the governor body communicating with each other through a clearance between the inner peripheral wall surface of the governor body and the outer peripheral wall surface of the governor valve and at least one pocket provided in each one of the input and output oil passage and recessed in a direction away from the rotational center of the rotational shaft to collect therein particles of swarf of foreign material in the working oil in the input and output passages.

Abstract: A timing control valve for use in the automatic transmission control apparatus for vehicles has a spring-backed spool which is actuated for movement to one position by the spring force or the spring force and the oil pressure to be applied to the brake B.sub.2 for causing a sun gear and a transmission gear case to be engaged by way of a one-way clutch, and is actuated for movement to the other side by a counteracting force provided by a line pressure and an oil pressure to be applied to the reverse clutch C.sub.2, whereby the timing control valve permits the brake B.sub.1 to be operated for directly connecting or disconnecting the sun gear and transmission case by controlling the timing of such operation of the brake B.sub.1 in response to changes in the throttle opening degree, and particularly permit a smooth downshifting without a one-way clutch.