Abstract: A drivetrain for an electric vehicle includes a motor, a pair of drive shafts, and a compact and simple transmission mechanism composed of two planetary gear units to achieve a differential function as well as a large reduction speed ratio. The transmission mechanism has an input element coupled to the motor, one output element coupled to one of the drive shafts, coupling elements coupling the units together, a fixed element, and another output element coupled to the other of the drive shafts. The torque received at the input element is increased and transmitted to one output element, and the torque is also reversed between the one output element and one of the coupling elements. After transmission through the coupling elements the torque is again reversed and then transmitted to the other output element.

Abstract: A drive system provides a smooth start for a vehicle and converts excess kinetic energy accompanying the difference in speed between the engine and the drive wheels occurring during starting into electrical energy for storage in a battery. The drive system includes a gearbox having at least a first gear element connected to an output shaft of an engine, a second gear element connected to a drive wheel of a vehicle and a third gear element for, by applying a braking torque to the third gear element, reducing the speed of rotation input from the first gear element and outputting it to the second gear element. An engaging element provides selective connection to any of the gear elements for mechanically connecting the output shaft of the engine to the drive wheel.

Abstract: A shift control system for an automatic transmission including a first transmission assembly for changing gear ratios in accordance with the release or engagement of a first frictional engagement system and a second transmission assembly connected in series to the first transmission assembly for changing gear ratios in accordance with the engagement or release of a second frictional engagement system. It includes a decision system for deciding whether or not the automatic transmission should execute the gear changes and a time lag controller for making the time lag for the second frictional engagement system to be engaged shorter than the time lag for the second frictional engagement system to be engaged for another gear change when the automatic transmission is to execute the gear changes.

Abstract: A lock-up apparatus in a torque converter includes a first oil chamber (25) and a second oil chamber (26) delimited by a lock-up piston (21), a first oil line system (A) communicating with the first oil chamber (25), and a second oil line system (B) communicating with the second oil chamber (26). An orifice (36) and an oil line (37) for directly communicating the first oil line system (A) and the second oil chamber (26) are provided in an output shaft (20) and a turbine hub (19), respectively. Accordingly, the first oil chamber (25) and the second oil chamber (26) are not directly communicated. As a result, not only is shock produced at release from the locked up state mitigated by the orifice (36) and oil line (37), but it is also possible to reliably prevent a decline in transmission torque capacity in the lock-up ON state.

Abstract: A hydraulic breather for a valve body in an automatic transmission, in which is disposed hydraulic equipment, for example, linear solenoid valves. The breather separates oil in the oil pan from the oil in the hydraulilc equipment when the automatic transmission is at work while allowing clean oil from the oil pan to enter the hydraulic equipment when the automatic transmission is at rest. The breating hole is provided in the form of an oil passage extending from hydraulic equipment within the valve body and includes an open-end section disposed in an upper part of the valve body. The open-end is located at a point higher than the working oil level in the automatic transmission. When the automatic transmission is at work, oil in the oil pan is used to lubricate, so the oil level is at its lowest level and the open-end section is above that oil level and thereby connects with air space in the valve body.

Abstract: An accumulator back pressure control device for an automatic transmission regulates the accumulator back pressure when a shift valve is switched. For example, when up-shifting from first to second speed, when the second brake starts to engage by switching of a shift valve, the rotational speed of the input is varied to change the output torque of the transmission gear mechanism. By detecting the change in rotational speed with a sensor, a pressure control valve (linear solenoid) is controlled by signals from a control unit so that the control pressure is regulated at a desired time. Thus, for example, the change of hydraulic pressure at a control pressure port regulates the oil source pressure (line pressure) and applies such regulated pressure to the back pressure chamber of an accumulator to change the back pressure of the accumulator.

Abstract: A primary regulator valve has a cutback port which regulates a line pressure to increase, at the first speed of D range, a throttle pressure is applied to the cutback port through a cutback valve. The primary regulator valve sets the line pressure from a line pressure port higher. The cutback valve has a spool which is compressed in one direction. A first control chamber which is connected to a hydraulic servo (for example, a second brake hydraulic servo) which hydraulic pressure is applied at more than the second speed is formed against the pressing direction, a second control chamber which is connected to a hydraulic servo (for example, a second-coast brake hydraulic servo) to limit a coasting condition of the second speed is so formed as to follow the above pressing direction. At the second speed of second range, the cutback valve, as the first speed of D range, the throttle pressure is applied to the cutback port.

Abstract: A reverse-engaging condition is prevented by a reverse inhibit valve operated by the solenoid valve even if a shift lever is operated to a reverse range at forward running. A solenoid valve controlling a 1-2 shift valve is "OFF" when controlling a manual valve to a reverse range under 7 km/h of a vehical speed. The reverse inhibit valve is at a right-half position. Therefore, the hydraulic pressure from the reverse range port of the manual valve runs through oil passages and supplied to the hydraulic servos. At forward running over 7 km/h the solenoid valve is switched "ON", the reverse inhibit valve is switched to a left-half position and oil passages are isolated. When the solenoid valve is switched at forward running, a hydraulic pressure from a R range port of the manual valve does not operate on a difference of cross sectional areas of lands of the reverse inhibit valve, so that the reverse inhibit valve is kept at the right-half position together with a pressing force of a spring therein.

Abstract: A transfer portion connected to the output shaft of a transmission portion has a front planetary gear unit the output element of which is connected to the front wheels and a rear planetary gear unit the output element of which is connected to the rear wheels, the two units being connected to each other by a common element. The output shaft of the transmission portion is directly connected to the input element of either of the planetary gear units, while the same is connected to the input element of the other planetary gear unit via a clutch C.sub.3. Furthermore, the input element of the other planetary gear unit is connected to the case via a brake B.sub.4. Therefore, the reduction function can be realized in cooperation with the two planetary gear units. As a result, the four-wheel drive device is lightened.

Abstract: A supplying port connecting to a supplying-side hydraulic pressure is arranged in a lock-up control valve. When the lock-up relay valve is switched ON (right half position), a supplying hyraulic pressure is supplied to a second oil chamber through an oil passage, led to a first oil chamber through an orifice and drained to a draining hydraulic oil passage through the oil passage. At this state in the lock-up control valve an inner pressure of the first oil chamber operates on a chamber through the oil passage, while an inner pressure of the second oil chamber operates on a chamber through the oil passage, and a controlling pressure from a linear solenoid valve operates on the controlling chamber. When the controlling pressure from the controlling chamber decreases by a deceleration of a vehicle speed, a valve closes a draining oil port and a drain port and increases an inner pressure of the first oil chamber.

Abstract: A hydraulic control apparatus for controlling a shifting action of a hydraulically operated frictional coupling device of an automatic transmission connected to a vehicle engine, from a neutral position to a forward drive position, in response to an operation of a shift lever.

Abstract: Hydraulic pressure which is regulated by a pressure control valve (linear solenoid valve) is applied to a hydraulic servo of a brake which is actuated when an engine-brake is effected. When the engine-brake is effected, a hydraulic pressure which is modulated by a modulator valve controlled by the linear solenoid valve is applied to the brake hydraulic servo. The pressure control valve provides high hydraulic pressure when vehicle speed is high based on signals from a speed sensor, and provides low hydraulic pressure when vehicle speed is low based on signals from the speed sensor, so that an engine-brake force is adequately controlled in accordance with vehicle speed. Furthermore, if a foot brake sensor is employed, the hydraulic pressure in accordance with vehicle speed can be made low when the engine-brake is effected with the foot brake applied.

Abstract: A separate plate for use in a valve body of an automatic transmission has a gasket bonded to each side of the separate plate. The gasket is provided with boxes which are different in configuration from bores provided in the separate plate. Bores are punched out in the separate plate and the gasket coated with an adhesive, separately from each other, and then the separate plate and the gasket are bonded together in one unit. Accordingly, it is possible to provide a separate plate having improved assembling efficiency and superior resistances to heat, oil and rupture.

Abstract: A hydraulic circuit for controlling an automatic transmission. The hydraulic circuit has a control valve connected between a shift valve and a hydraulic servomotor for actuating a frictional engagement element such as a brake in a main transmission unit. The control valve is controlled by a signal from a control means in such a manner that, when the hydraulic servomotor is drained by the operation of the shift valve to disengage the brake, the engagement of a frictional engaging element in another transmission unit is synchronized therewith.

Abstract: A rotational speed detecting device for detecting the rotational speed of a predetermined element of a shifting unit is provided for at least one of a main shifting unit and a sub-shifting unit. A control is provided for controlling a predetermined friction engaging element of at least one of the shifting units according to signals from the rotational speed detecting device, so that shifting operations of both the shifting units will be synchronized when both the units are shifted. Therefore, the output of speed of the transmission is not temporarily increased or decreased and thus, smooth shifting is obtained.

Abstract: A cut-back pressure control device for a multi-speed automatic transmission includes a cut-back valve that has a spool which is controlled by both hydraulic pressure which changes in response to shifting of a sub-transmission unit between high-speed and low-speed modes and a hydraulic pressure which is established by the operation of the main transmission unit at 2nd or higher speeds. The spool is moved to a position where it interrupts the cut-back pressure when the main transmission unit selects the 1st speed while the sub-transmission unit is in the low-speed mode, whereas, when the sub-transmission unit is in the high-speed mode or when the main transmission unit selects the 2nd or a higher speed, the spool is held at a position at which it permits the supply of the cut-back pressure.

Abstract: An oil pass for communicating a hydraulic servo a change-over valve is provided with an orifice and a by-pass disposed parallel to one another. The by-pass is provided with a sequence valve. When the hydraulic servo is subjected to less than a predetermined pressure, the sequence valve communicates to the change-over valve and the hydraulic servo through the by-pass, and when the hydraulic servo is subjected to a pressure that is higher than the predetermined pressure, the sequence valve is cut off.

Abstract: An accumulator control device for controlling the back pressure of an accumulator includes an accumulating control valve having a first port communicating with a control oil source and a second port communicating with an accumulator back pressure chamber. The accumulator control valve is controlled by a oil pressure from a shift control. According to the control position of the shift control, the accumulator control valve controls the communicating state of the first and second ports to increase or decrease the back pressure of the accumulator.

Abstract: A lock-up clutch control device for an automatic transmission having a torque converter with a lock-up clutch and a speed changing gear mechanism including a sub-transmission unit and a main transmission unit. The device has a lock-up operation device for producing a control signal when the sub-transmission unit is in the higher speed mode or when the main transmission unit selects 2nd or a higher speed gear. The control signal is delivered to a lock-up relay valve which operates effectively while it receives the control signal. Therefore, the torque converter can be locked up at 2nd or higher speeds of the automatic transmission which, because of various combinations of the states of the sub-transmission and main transmission units, outputs multiple speed.

Abstract: A bearing lubrication system for an extension housing of automatic transmission, including an extension housing connected to a transmission case, a valve casing of a hydraulic control system fastened to the transmission case, a transmission output shaft supported in the extension housing, and a sleeve yoke splined to the output shaft and fitted in a bearing portion of the extension housing through a bearing, characterized in that the lubrication system is provided with a forced lubrication means comprising: a bearing lubricant tapping passage branched off from a lubricant oil passage or line pressure conduit in the transmission case or in the valve casing; a bearing lubricant supply passage communicating the bearing lubricant tapping passage with the bearing portion of the extension housing; and a flow control throttle provided in the bearing lubricant tapping passage or in the bearing lubricant supply passage.