Patent · US Expired

Pressure regulating valve in a hydraulic control system for an automatic transmission

US5868167A · kind A · utility

20Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 30, 1996
Grant dateFeb 9, 1999
Priority date
Expiry dateDec 30, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/86622
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A pressure regulating valve in a hydraulic control system for an automatic transmission according including a pressure regulating unit having a spool made slidable in a valve sleeve 10. An electromagnetic unit for causing a hollow core (or stator) is provided to attract a plunger (or movable element) arranged on a push rod communicating with the spool. The spool is moved by a spool moving mechanism in a direction to increase the flow from an input port to an output port to thereby raise an output pressure from an output port when the output pressure is lowered by a leakage. The spool position is controlled to control the output pressure in accordance with a balance among a spring force of spring means fitted in the valve sleeve, a feedback force resulting from the output pressure, and an electromagnetic attraction to be established in response to an electric signal provided to the electromagnetic unit having the hollow core and the plunger. In another embodiment, an input pressure feedback port is provided in the valve sleeve, and spool position control is additionally dependent upon an input pressure feedback force provided to the input pressure feedback port.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.