Hydraulic servo-mechanism for an automatic transmission

Patent 5881858 Issued on March 16, 1999. Estimated Expiration Date:

December 27, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

2227245

2513192

2633712

2769307

Speed change control system for an automatic transmission
Patent #: 4388986
Issued on: 06/21/1983
Inventor: Umezawa

Hydraulic servo device with built-in accumulator
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Inventor: Sugano

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Patent #: 4787494
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Patent #: 4790211
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Inventor: Iwatsuki , et al.

Brake system for automatic transmission
Patent #: 4930373
Issued on: 06/05/1990
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Hydraulic controller for an automatic transmission
Patent #: 5020393
Issued on: 06/04/1991
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Inventors

Assignee

Aisin AW Co., Ltd.

Application

No. 777179 filed on 12/27/1996

US Classes:

192/86, Double acting92/63, With separate biasing means for a working member188/77W, Wrap band type188/347With hydraulic quick-slack-take-up pulsator

Examiners

Primary: Bonck, Rodney H.

Attorney, Agent or Firm

Lorusso & loud

International Class

F16D 049/12

Foreign Application Priority Data

1996-02-09 JP

Abstract

A hydraulic servo-mechanism for an automatic transmission, including a hydraulic servo for applying a band brake to engage a band to a drum. The hydraulic servo includes a rod which is selectively positionable to an apply position for applying the band brake, a standby position in which the rod is retracted by a predetermined extent in a release direction from the apply position, and a retracted position in which the rod is further retracted in the release direction from the standby position to release the band brake.