Rapid apply servo for a brake band of an automatic transmission

Patent 5711403 Issued on January 27, 1998. Estimated Expiration Date:

November 4, 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

2859593

Regulator valve
Patent #: 4111283
Issued on: 09/05/1978
Inventor: Hastings, Jr.

Brake band servo for automatic transmission Patent #: 5544565
Issued on: 08/13/1996
Inventor: Van Selous

Inventors

Application

No. 743586 filed on 11/04/1996

US Classes:

188/77W, Wrap band type91/29, By pressure rise in first path91/32Activation of one path disables second path

Examiners

Primary: Poon, Peter M.

Attorney, Agent or Firm

Mckenzie; Frank G.

Foreign Patent References

3417703 DE. 01/12/1987
3417784 DE. 01/12/1988
84433 JP 05/12/1985
40-4019465 JP 01/12/1992
40-4107329 JP 04/12/1992

International Class

F16D 051/00

Abstract

A servo for operating a brake band in an automatic transmission includes a transmission casing and servo cover defining a servo cylinder, a servo piston supported for displacement within the cylinder, first and second sealed volumes within the cylinder, a valve for connecting the fluid sump to one pressure area and for closing that connection and opening a connection to line pressure while maintaining the first pressure area connected to line pressure.