Mazda Motor Corporation

Shinya Yamamoto

Shinya Kamada

Tatsuhiko Iwasaki

Tatsutoshi Mizobe

Junichi Doi

Masami Nishida

Norio Iwashita

Takamichi Teraoka

Tokimori Saka

Hideo Toyota

Naohiro Sakaue

Katsuya Ohuchi

Shigemi Ohsaki

On an input shaft are provided in order from a side of an engine a torque converter with a lock-up clutch, a first planetary gear set as a multiplying mechanism, a counter drive gear outputting a rotational drive force to a countershaft, a second planetary gear set as a speed-change element, a third planetary gear set as a speed-change element. Accordingly, there can be provided an automatic transmission for six forward speeds with plural planetary gear sets, clutches and brakes that can properly reduce a clutch capacity and restrain gear noises with its compact and light-weighted structure.

Automatic transmission

A method of producing a mechanical component with superior fatigue strength comprises the steps of casting melted ferrous alloy which includes carbon within the range of 0.3% to 0.45% by weight, silicon within the range of 1.3% to 2.0% by weight, chromium within the range of 5.0% to 6.0% by weight, molybdenum within the range of 1.0% to 1.5% by weight, vanadium within the range of 0.8% to 1.2% by weight, manganese not more than 0.5% by weight, and iron of the major remainder, into an untreated mechanical component by the use of a casting mold formed through a lost-wax process; annealing the untreated mechanical component to produce an unfinished mechanical component; machining roughly the unfinished mechanical component having been annealed; quenching and tempering in sequence the unfinished mechanical component having been roughly machined; and finishing the unfinished mechanical component having been quenched and tempered to obtain a finished mechanical component.

Method of producing a mechanical component with superior fatigue strength

Growing community of inventors

Hiroshima, Japan

Shinya Yamamoto