Automatic transmission
AssigneeMazda Motor Corporation
InventorsShota Yamakawa, Tatsuhiko Iwasaki, Tomotaka Ishizaka
Life of this patent
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Abstract
An automatic transmission is provided, which includes a friction engaging element. The friction engaging element includes a plurality of friction plates disposed inside a transmission case, a piston configured to cause the plurality of friction plates to be engaged with each other, and a spring configured to bias the piston. The spring includes a first spring and a second spring with a longer free length than the first spring, and the first spring and the second spring are aligned in circumferential directions of the transmission case.
Claims4
An automatic transmission comprising a friction engaging element, the friction engaging element including:
- a plurality of friction plates disposed inside a transmission case;
- a piston configured to cause the plurality of friction plates to be engaged with each other;
- a spring configured to bias the piston, the spring including a first spring and a second spring with a longer free length than the first spring, and the first spring and the second spring being aligned in circumferential directions of the transmission case;
- and
- a hydraulic chamber to which hydraulic fluid is supplied, the hydraulic fluid biasing the piston,
- wherein the hydraulic chamber includes a first hydraulic chamber for engagement to which hydraulic fluid to bias the piston in an engaging direction is supplied to cause the plurality of friction plates to be engaged with each other, and a second hydraulic chamber for release disposed at an opposite side of the piston from the first hydraulic chamber for engagement, the second hydraulic chamber for release being supplied with hydraulic fluid to bias the piston in a releasing direction opposite from the engaging direction,
- wherein the second hydraulic chamber for release is formed to have a smaller outer diameter than the first hydraulic chamber for engagement, and
- wherein a biasing force receiving member configured to receive the biasing force of the first spring and the second spring is coupled to the piston and is disposed at an outer circumferential side of the second hydraulic chamber for release.
Dependencies are inferred from the claim text.