Abstract: A transmission case of an automatic transmission is formed with a fluid passage fluidly connecting a fluid pressure pump to a hydraulic control valve body for controllably operating a planetary gear system disposed in the case. The fluid passage is located adjacent a closed end of the transmission case and connected to control valve body in order to reduce the overall length of the transmission case in its axial direction.

Abstract: A transmission throttle valve for use in a hydraulic control system of an automotive automatic power transmission, comprising a valve plunger movable with the accelerator pedal of an automotive vehicle and, a valve spool engaging the valve plunger through a spring urging the valve plunger and the valve spool to axially move in opposite directions relative to each other for producing a fluid pressure variable with the displacement of the accelerator pedal, wherein the valve spool is formed with an axial bore open at both ends and has the valve plunger slidably passed through the bore while the valve plunger is formed with a laterally enlarged axial portion forming a variable-volume space in which the fluid pressure developed by the transmission throttle valve is to be admitted to urge the valve plunger to axially move against the force of the spring so as to save the driver's effort for depressing the accelerator pedal.

Abstract: A set of planetary pinions forming part of a planetary gear system are meshed with a ring gear which is secured to a power output shaft operatively connected to a final drive unit. The ring gear is formed at its outer peripheral surface with teeth of worm which mesh with a worm wheel connected to a governor valve body for producing a governor pressure in accordance with the rotational speed of the power output shaft.

Abstract: In a hydraulic control system of an automatic power transmission is provided a first-second gear shift valve which is to be acted upon through only one fluid inlet port by a signal fluid pressure representative of a manual first forward drive range selected at the manually operated gear shift lever, the port being used not only as the port to receive the signal fluid pressure but as a switching port so that the shift valve is conditioned to produce the first gear in the transmission mechanism in the presence of the signal fluid pressure.

Abstract: A cap member to cover a cylindrical portion of a governor case of an automatic transmission is shaped to have a cylindrical wall as its open end portion with an inner diameter larger than the outer diameter of the cylindrical portion of the governor case, and a plurality of circumferentially arranged arcuate slits are formed at intervals in the cylindrical wall of the cap. The cap put on the governor case is easily and quickly fastened by means of a resilient fastener wire which is curved into a generally arcuate shape and bent locally so as to form a plurality of V-shaped inward projections at intervals corresponding to the intervals between the slits of the cap. The fastening is completed by fitting the fastener wire around the cylindrical wall of the cap and inserting the inward projections respectively into the slits of the cap. Preferably an annular flange is formed in the cylindrical portion of the governor case as a retainer for the fastener wire.

Abstract: Grooves formed in a cylindrical member of the high-and-reverse clutch are designed to receive therein detents or teeth of clutch plates respectively and each of openings formed in a drum member of forward drive clutch is designed to receive therein at least two adjacent teeth of each clutch plate so that these high-and-reverse and forward drive clutches can use common clutch plates.

Abstract: An output gear of a power transmission is drivably connected through an idler gear to an input gear of a final drive unit having a differential. The idler gear is mounted through a pair of tapered roller bearings on a sleeve shaft which is supported by opposite two walls between which the idler gear is located. An end portion of the sleeve shaft is adjustably received within a recess formed at the inner surface of one of the walls in a manner that a bolt securing the sleeve shaft is screwed into a boss formed in the recess of the wall.

Abstract: First and second bearings are arranged on either side of an output gear of the transmission to bear the same, and third and fourth bearings are arranged to bear an idler gear which meshes with the output gear to transmit the revolution of the output gear to a final drive assembly mounted on a side of the transmission. The first bearing is supported by part of a converter housing, the second bearing is supported by a separate member disposed within and detachably connected to the converter housing, and the third and fourth bearings are supported on a support which extends between the housing and the separate member.

Abstract: In a parking mechanism of an automotive automatic transmission having a park gear, a parking pawl which can mesh with the park gear, a cam mounted on an actuator rod to change the position of the pawl and an actuator support fixed to the inside of a transmission case to slidably support the actuator rod, the actuator support is produced by press-forming of a sheet metal as a one-piece member whose middle portion is shaped so as to support and guide the actuator rod and the cam with the purpose of reducing production cost. The actuator support is easily fixed to the transmission case by forming two slits in the transmission case at the stage of casting the case and inserting two end portions of the actuator support respectively into these two slits each together with a leaf spring.

Abstract: A governor is disclosed in which dust which may comprise steel powder, fine particles of sand and so on will be removed from a hydraulic working fluid by subjecting the working fluid to centrifugal force. A fluid passage for the working fluid is formed in a housing of the governor and a chamber communicates with the passage at the opening. The fluid passage has an opening located such that dust contained in working fluid will enter into the chamber through the opening while the housing is rotating. Within the chamber working fluid will be stagnant and dust sedimented.

Abstract: A positioning plate holding a transmission of a motor vehicle through a manual gear selector lever in position has a sector with a notch in the sector arc. A locking plunger with a projection is engaged by the notch when the transmission is in free gear. The engine may be started but the transmission remains locked in the free gear until the driver fastens his seat belt, by which the locking plunger is retracted from the notch and the transmission may be shifted into drive gears.