Aisin Aw Co., Ltd.

Naoji Katou

Masahiro Hayabuchi

Satoru Kasuya

Hiroshi Katou

Kazumasa Tsukamoto

Takao Taniguchi

Hiroaki Sanji

Susumu Kato

Masashi Kitou

Akitoshi Katou

Naoki Takabayashi

Yasuhiro Asai

Kaneyoshi Nakagawa

Hiroshi Ota

A first element of a duplex planetary gear set is selectively coupled to an input shaft via a third clutch, or is selectively fixed via a first brake. A second element is selectively coupled, via a second clutch, to an intermediate shaft that is directly coupled to a speed-increasing element of a simplex planetary gear set which increases the rotational speed of the input shaft, or is selectively fixed via a second brake. A third element is directly coupled to an output shaft. A fourth element is selectively coupled to the input shaft via a first clutch. Therefore, by increasing the speed of the rotation of the input shaft by the simplex planetary gear set and transferring it to the duplex planetary gear set, it is possible to reduce the torques on individual components of an automatic transmission and therefore to reduce the sizes of the individual components and the capacities of the individual friction engagement elements.

Automatic transmission

The output rotation of an engine is transmitted to a drive member when a vehicle starts moving, and the drive member is connected to a carrier of a speed-increasing planetary gear via a start clutch. Upon engagement of the start clutch, the rotation of the drive member is accelerated by the speed-increasing planetary gear and then transmitted to an input shaft that is directly connected to a ring gear. Such rotation transmitted to the input shaft is shifted to a plurality of speeds and transmitted to an output shaft by using a plurality of friction engagement elements to selectively connect or fix elements of a single planetary gear set and a multiple planetary gear set that is connected to the output shaft.

A double pinion planetary gear unit includes a first sun gear, a second sun gear, a plurality of short pinions, a plurality of long pinions, a ring gear and a carrier. The carrier includes a first flange portion that supports an end side of the short pinions and an end side of the long pinions, a cylindrical portion that is connected to the first flange portion and that forms a cover for an outer peripheral side where the short pinions and the long pinions mesh with each other, a second flange portion that supports another end side of the long pinions, and a plurality of bridge portions that extend from the second flange portion toward the short pinions and that support another end side of the short pinions.

Planetary gear apparatus

Growing community of inventors

Anjo, Japan

Naoji Katou