Toyota Jidosha Kabushiki Kaisha

Toyota Motorsport Gmbh

Kabushiki Kaisha Toyota Chuo Kenkyusho

Tomohiro Yoshimura

Akihiko Ichikawa

Shinichi Takeuchi

Jun Yabuta

Lars Van Leeuwen

Klemens Pollmeier

Andree Miller

Isamu Shiotsu

Patrizio Agostinelli

Junichi Muraoka

Tomomitsu Terakawa

Kotaro Hoshihara

Yuuki Masui

A control apparatus for a vehicular transmission including at least one dog clutch each having a first dog member mounted on a first shaft such that the first dog member is rotated together with the first shaft, and at least one second dog member each mounted to be axially adjacent to the first dog member and rotatable relative to the first shaft, first gears each mounted to be rotatable relative to the first shaft and provided with the second dog member, second gear which are mounted such that the second gears are rotated together with a second shaft parallel to the first shaft, and which mesh with the respective first gears, and a shifting mechanism for selectively placing each dog clutch in an engaged or released state. The control apparatus includes: a first calculating portion for detecting to a rotary angular position of the first shaft, and calculating a rotary angular position of the first dog member on the basis of the detected rotary angular position of the first shaft; a second calculating portion for detecting a rotary angular position of the second shaft, and calculating a rotary angular position of each second dog member on the basis of the detected rotary angular position of the second shaft; and an engagement control portion for controlling the shifting mechanism on the basis of the rotary angular positions of the first and second dog members, for engagement of the first and second dog members with each other.

Control apparatus for vehicular transmission

A dog clutch includes a gear () mounted on a power transmission shaft (), first and second dog rings (), a fork (), springs (), and cam grooves (). The cam grooves () each include a first slope surface () inclined from the axial direction toward the positive rotation direction as the first slope surface () approaches the gear () and a second parallel surface () parallel to the axial direction. The first dog ring () includes first cam protrusions () to be engaged with the respective first slope surfaces (), and the second dog ring () includes second cam protrusions () to be engaged with the respective second parallel surfaces (). This structure prevents the dog rings and the fork from coming into contact with each other, thereby avoiding generation of abrasion and increasing the transmission efficiency.

Dog clutch and transmission

A vehicle transmission has a plurality of gear positions that are to be selectively established, and includes: an input shaft; a first shaft; a second shaft; an output shaft; at least one first drive gear disposed on the first shaft; at least one second drive gear disposed on the second shaft; at least one driven gear disposed on the output shaft; a dog clutch connecting and disconnecting between the input shaft and each of the first and second shafts; and a synchronous meshing apparatus. The synchronous meshing apparatus connects and disconnects between each of the first and second shafts and the output shaft, and, when connecting between each of the first and second shafts and the output shaft, establishes a power transmission path from each of the first and second shafts to the output shaft via a selected one of the at least one first or second drive gear.

Vehicle transmission

A first dog ring and a second dog ring are biased toward each other by means of springs. When the first dog ring and the second dog ring are moved away from each other, bias force produced by the springs is applied to the second dog ring in a direction to draw the second dog ring toward the first dog ring. Accordingly, when the first dog ring is moved away from the second dog ring during shifting, the second dog ring is drawn toward the first dog ring under the bias force, and third engaging teeth of the second dog ring and meshing teeth of a first-speed gear are promptly disengaged from each other.

Transmission for vehicle

A dog clutch includes a rotating member including first dog teeth, an annular dog ring including second dog teeth, and an annular dog sleeve. The rotating member includes first protrusions protruding radially outwardly from the outer circumferences of crests or troughs of the first dog teeth, the dog sleeve includes second protrusions that are configured to come into contact with the first protrusions in a circumferential direction when the dog sleeve moves toward the rotating member in an axial direction, and the first dog teeth and the second dog teeth are disposed at positions at which the first dog teeth and the second dog teeth are able to be engaged with each other in the circumferential direction in a state in which the first protrusions and the second protrusions are in contact with each other.

Dog clutch

Growing community of inventors

Toyota, Japan

Tomohiro Yoshimura