Abstract: Since the first-speed-ratio counter gear is carried by the first countershaft, the second countershaft carries other counter gears which transmit the relatively small drive torque, such as the forth-speed-ratio counter gear, the second-speed-ratio counter gear and the sixth-speed-ratio counter gear. Thus, there can be provided the twin-clutch transmission with two countershafts disposed coaxially which can surely obtain the advantage of making the transmission for transmitting the sufficiently large drive torque compact.

Abstract: A power transmission apparatus comprises a case defining a cavity, moveable parts arranged within the cavity, fixed parts arranged within the cavity, the fixed parts including parts moveably supporting the moveable parts, a wall at least partly constituting said case, and a thin wall portion formed in the wall, the thin wall portion being constantly pressed in an outward direction of the cavity by one of the fixed parts, so as to increase its rigidity. Membranous vibration of the case wall may be effectively controlled and the radiation noise from the transmission apparatus can be reduced without increasing the thickness of the transmission case wall or arranging ribs on it.

Abstract: Since the first-speed-ratio counter gear is carried by the first countershaft, the second countershaft carries other counter gears which transmit the relatively small drive torque, such as the forth-speed-ratio counter gear, the second-speed-ratio counter gear and the sixth-speed-ratio counter gear. Thus, there can be provided the twin-clutch transmission with two countershafts disposed coaxially which can surely obtain the advantage of making the transmission for transmitting the sufficiently large drive torque compact.

Abstract: An automobile powertrain has at least an engine placed in an engine room and oriented so that its crankshaft is directed transversely, and a transmission placed in the engine room behind the engine. The transmission has input and output shafts arranged coaxially with each other and directed parallel to the crankshaft of the engine. An engine clutch is directly connected to the crankshaft, and a power transfer arrangement is disposed oppositely to the engine with respect to the engine clutch and operationally couples the engine clutch to the input shaft so as to transmit engine output to the transmission. The transmission, engine clutch and power transfer arrangement are independently accommodated in separate chambers of a single unit powertrain case. The transmission chamber and the power transfer chamber are connected to each other by an oil passage through which the input shaft extends from the transmission to the power transfer.

Abstract: An automobile powertrain has at least an engine placed in an engine room and oriented so that its crankshaft is directed transversely, and a transmission placed in the engine room behind the engine. The transmission has input and output shafts arranged coaxially with each other and directed parallel to the crankshaft of the engine. An engine clutch is directly connected to the crankshaft, and a power transfer arrangement is disposed oppositely to the engine with respect to the engine clutch and operationally couples the engine clutch to the input shaft so as to transmit engine output to the transmission. The transmission, engine clutch and power transfer arrangement are independently accommodated in separate chambers of a single unit powertrain case. The transmission chamber and the power transfer chamber are connected to each other by an oil passage through which the input shaft extends from the transmission to the power transfer.

Abstract: An automotive powertrain has an engine placed within an engine compartment and oriented so that its crankshaft is directed transversely. The powertrain also has an automatic transmission placed in the engine compartment behind the engine, and a torque converter operationally coupled to the crankshaft and input shaft of the transmission. Input and are output shafts of the transmission are arranged coaxially with each other and are directed parallel to the crankshaft of the engine. A hydraulic control valve body, through which controlled hydraulic pressure is applied to the transmission so as to shift the transmission, is placed in a space defined below a horizontal plane including a top end of the transmission and behind a vertical plane including an axis of rotation of the crankshaft.

Abstract: A powertrain includes an engine and a transmission and has a center inertial axis extending in a transverse direction of the vehicle body. The powertrain is mounted on the vehicle body for inertial movement about the center inertial axis by a pair of elastic mountings, disposed on opposite sides of the powertrain and not below the inertial axis. Another elastic mounting is disposed behind the powertrain. An exhaust pipe assembly, extending rearwardly and down behind the powertrain from the engine, is flexibly supported by a retainer connected, either directly or through the other elastic mounting, to the powertrain.

Abstract: An engine unit includes an engine and a power train having a transmission and the engine unit is mounted sideways on a vehicle body with the power train positioned rearward of the engine. The engine and the power train are housed in a single engine housing and an oil pan common to the engine and the power train is mounted on the lower side of the engine housing below the engine and the power train. The length of the oil pan in the transverse direction of the vehicle body is smaller than the engine housing and auxiliary mechanisms are disposed in the space on one side of the oil pan and below the engine housing.

Abstract: A power train includes a transmission having transmission shafts, with axes of rotation parallel to a crankshaft of an engine. The transmission shafts extend in a transverse direction of a vehicle. A drive axle is connected to drive wheels of the vehicle , and a drive axle differential differentially drives the drive wheels through the drive axle. A center differential is provided to differentially drive the front and rear drive wheels. The drive axle has an axis of rotation placed below and parallel to the axis of rotation of the transmission shafts. The drive axle differential and center differential are disposed side by side in the transverse direction of the vehicle body on, and in alignment with, the axis of rotation of the drive axle. The drive axle differential is located closely adjacent to the transmission in the transverse direction.

Abstract: A drive shaft for driving supplemental apparatuses is disposed in or penetrates an oil pan disposed under an engine in order to provide a compact supplemental apparatus layout or arrangement. In the oil pan, a supplemental apparatus drive unit, including the drive shaft, an idle gear meshing with an output gear fixed on an engine crankshaft, and a chain for transmitting drive power from the idle gear to the drive shaft, is supported, and is simultaneously assembled so as to be linked with the idle gear and the output gear when the oil pan is assembled to the engine. The output gear is preferably fixed on the inner side of an endmost journal of the crankshaft to reduce vibrations from the crankshaft. Moreover, providing a damper associated with the output gear fixed to the crankshaft reduces the vibrations from the crankshaft.

Abstract: A power train includes a transmission disposed in a transverse direction of a vehicle, in which an engine crankshaft extends. The power train has a wheel drive shaft, disposed in alignment with a transmission shaft, a front differential, having differential output shafts aligned with the transmission shaft, and a speed reduction gear, disposed between the transmission shaft and differential input shaft. The speed reduction gear has an input gear, having an axis of rotation placed parallel to the transmission shaft. The transmission shaft is one of input shaft and output shaft, having axes of rotation which are placed parallel to the engine crankshaft. The wheel drive shaft and differential output shaft are aligned with the one of the transmission input and output shafts. The speed reduction gear, connected to the one of the transmission input and output shafts, is preferably parallel to both of the transmission input and output shafts.

Abstract: An engine unit includes an engine and a power train which are disposed in parallel to each other. The power train includes a transmission and a differential. The engine and the power train are housed in one engine housing formed of upper and lower parts which are mated with each other along respective mated surfaces. Upper halves of bearings for the crankshaft and upper halves of bearings for a rotational shaft of the power train are formed in the mating surface of the upper part of the engine housing and lower halves of bearings for the crankshaft and lower halves of bearings for said rotational shaft of the power train are formed in the mating surface of the lower part of the engine housing. The upper part of the engine housing is formed integrally with the cylinder block of the engine.

Abstract: A steplessly variable transmisison system for a vehicle, having a belt-pulley type transmission. An input shaft of the transmission consists of first and second shaft portions. A sleeve member is provided and is slidably splined on the first shaft portion. A driven gear is provided on the second shaft portion which is engageable with the sleeve member by a synchronizer mechanism. A reverse gear mechanism is also provided, the reverse gear of which is engageable with an outer gear formed on the circumference of the sleeve member. The sleeve member is slid by a shaft fork to thereby selectably engage the first shaft portion with the second shaft portion through either the synchronizer mechanism or the reverse gear mechanism. By selecting the engagement through the synchronizer mechanism, a forward driving transmission is implemented, whereas, by selecting the engagement through the reverse gear mechanism, a reverse driving transmission is implemented.

Abstract: A belt-pulley type steplessly variable vehicle transmission mechanism including a belt-pulley type transmission and a reverse gear mechanism both connected with an output differential gear device. A selecting mechanism is provided for connecting the input member alternately with the belt-pulley type transmission or the reverse gear mechanism so that the reverse drive can be made at a constant speed ratio.

Abstract: An automobile auxiliary power transmission having a synchronizer mechanism comprised of a synchronizer hub, a pair of synchronizer rings cooperating respectively with a low speed and high speed gears, and an axially movable synchronizer sleeve. The synchronizer sleeve has spline teeth for engagement with the synchronizer hub and with the synchronizer rings and the gears. The spline tooth on the sleeve has an axial length which is sufficient to engage with both of the synchronizer rings when it is disengaged from both of the gears. The arrangement is effective to make the shifting stroke of the sleeve smaller than that in conventional structures.

Abstract: A four-wheel drive automobile has a driving system which includes a transversely oriented engine unit, a transmission having input and output shafts which extend transversely of the car body, an inter-axle differential gear mechanism, front and rear inter-wheel differential gear mechanisms, and a differential gear lock mechanism. The inter-axle differential gear mechanism, the front inter-wheel differential gear mechanism and the differential gear lock mechanism are arranged coaxially with one another. The differential gear lock mechanism is provided in a part of said inter-axle differential gear mechanism which is positioned at a side of the front differential gear mechanism so that the front differential gear mechanism is located between inter-axle differential gear mechanism and the differential gear lock mechanism.