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U.S. Department of Energy
Office of Scientific and Technical Information

Hydraulic servo for friction coupling element of automatic transmission

Patent ·
OSTI ID:6095908

A hydraulic servo is described for a friction coupling element in an automatic transmission including a casing, comprising: an annular drum fixed to the automatic transmission casing and having an outer cylinder, as in inner cylinder, a sidewall connecting the outer and inner cylinders, and an intermediate cylinder connected to the sidewall between the outer and inner cylinders to divide the interior of the drum into outer and inner annular spaces; a piston slidably mounted within the outer annular space, between the outer and intermediate cylinders, the piston having a terminal axially extending guide sleeve portion; and return biasing means including: a connecting member having one end fixed to the piston and abutting the guide sleeve portion and the other end located in the inner annular space, between the inner cylinder and the intermediate cylinder; a retainer fixed to the inner cylinder, at a position axially inward of the guide sleeve with respect to the sidewall when the piston is fully retracted, and; return springs interposed within the inner annular space between the other end of the connecting member and the retainer.

Assignee:
Aisin-Warner Limited
Patent Number(s):
US 4690037
OSTI ID:
6095908
Country of Publication:
United States
Language:
English