US 7,247,114 B2 · Automatic transmission

Abstract

A forward/reverse change-over mechanism (3) of an automatic transmission comprises a forward clutch (5) inside a drum (7) with the base (7c) which rotates together with an input shaft (1). The forward clutch (5) engages by driving a piston (9) housed in the drum (7) by the oil pressure of an oil chamber (10) between a base (7c) and the piston (9). Projecting bearings (16) which seat the piston (9) are formed by press-forming at equal angular intervals concentrically with the axial center of the drum (7) in the base (7c). By installing a sensor body (18) which responds to the passage of depressions (17) formed underneath the bearings (16), the forward/reverse change-over mechanism (3) can be made compact and manufactured with a small number of parts and machining steps.

Claims7

Dependent claims

An automatic transmission which changes a rotation speed of an input shaft to output power, comprising:

a drum having a base which rotates together with the input shaft;
a piston housed in the drum;
an oil chamber formed in the drum between the base and the piston, the piston displacing parallel to an axial center of the drum according to an oil pressure supplied to the oil chamber;
plural projecting bearings formed on the base at equal angular intervals concentrically with the axial center to seat the piston;
depressions formed underneath the bearings;
and
a sensor body disposed facing the base which outputs a signal when the depressions pass by.

4 more elements

Dependencies are inferred from the claim text.

Automatic transmission

Life of this patent

Automatic transmission

Life of this patent

Abstract

Claims7