A COMPACT TRANSMISSION, INCLUDING A MAIN TRANSMISSION AND A SUBTRANSMISSION

摘要

A transmission for an automotive vehicle, including a manually controlled main transmission and an automatically controlled subtransmission. The main transmission includes a main casing within which are rotatably supported a tubular intermediate shaft and a power output shaft, in parallel. Several gear wheels on each of these shafts cooperate, and by their selective engagement various different speed driving ratios may be obtained between the shafts. One end of the intermediate shaft and one end of the power output shaft project from one end of the main casing. A power input shaft passes coaxially through the tubular intermediate shaft and is rotatably supported therein. The ends of the power input shaft project from the ends of the tubular intermediate shaft. The subtransmission includes a subcasing attached to the aforesaid one end of the main casing, and within the subcasing a planetary gear mechanism is arranged between the power input shaft and the tubular intermediate shaft so as, under the control of a fluid pressure actuator, either to couple these two shafts together directly, or to provide an increase of rotational speed from the input shaft to the intermediate shaft. A fluid pressure control device selectively supplies actuating fluid pressure to the actuator, and is located within the subcasing in a position axially opposing the end of the power output shaft. The end of the power input shaft remote from the subcasing is driven. The fluid pressure control device is automatically controlled according to operational parameters of the vehicle to selectively supply fluid pressure to the actuator.