Toyota Jidosha Kogyo Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Shoji Haga

Hajime Arai

Shuji Nagano

Akio Numazawa

Shuichiro Ida

Toshio Yoshinaka

Toshikazu Koide

An electric control apparatus for a transfer device in a part-time four-wheel drive vehicle is arranged to permit switchover of the transfer device from the two-wheel drive mode to the four-wheel drive mode when a difference in rotational speed between front and rear propeller shafts is smaller than a predetermined value and to prohibit switchover of the transfer device from the two-wheel drive mode to the four-wheel drive mode when the difference in rotational speed between the front and rear propeller shafts is larger than the predetermined value.

Electric control apparatus for transfer device in part-time four-wheel

A transmission including a main transmission and a subtransmission. The subtransmission is a planetary gear mechanism incoporating a sun gear, planetary pinions, and a ring gear. The main transmission incorporates a tubular intermediate shaft and an output shaft parallel to it, and several pairs of helical gears mounted on the shafts for transmitting rotational power between them. A driven power input shaft passes through the central hole of the tubular intermediate shaft, protrudes from its end, and is connected to a carrier which supports the planetary pinions. The ring gear is connected to the intermediate shaft. The handednesses of the helical ring gear and of at least one of the helical gear wheels on the intermediate shaft are so arranged that when the subtransmission is transmitting power in the speed increasing state, and that helical gear wheel is transmitting power to the power output shaft, the senses of the axial forces exerted on these two gears by the meshing contacts on their teeth are opposed, so that they tend to cancel one another.

Transmission and sub-transmission with mutually contending helical gears

A hydraulic fluid pressure control system for a transmission which is shifted between two speed stages via a hydraulic actuator. A line pressure regulation valve receives supply of fluid pressure from a pump and produces a regulated line pressure. A switching valve receives supply of this regulated line pressure and selectively supplies it as an operating pressure to the fluid actuator, according to the opening and closing of a pilot port. This operating pressure is also supplied to the line pressure regulation valve for increasing the regulated value of the line pressure when the fluid actuator is being operated.

Transmission fluid pressure control device with two stepped line

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.

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Toyota, Japan

Shoji Haga