Patent · US Expired

Hydraulic control system for automatic transmission of multiple clutch type

US5851164A · kind A · utility

13Cited by
14References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 11, 1997
Grant dateDec 22, 1998
Priority date
Expiry dateApr 11, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S477/906
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

In a hydraulic control system for an automatic transmission of multiple clutch type for use in a motor vehicle, a shift valve which inverts the supply and cutoff of working oil for a hydraulic actuator serving to change-over gear shift stages is provided with a spool valvule and a clutch-oil-pressure supply port (as shown in FIG. 1). Even when a solenoid valve for controlling the shift valve has failed, a clutch oil pressure is supplied from the clutch-oil-pressure supply port so as to hold the switchover position of the spool valvule and to keep the gear shift stage already established. Thus, the hydraulic control system prevents an engine speed from rising or the motor vehicle from locking due to the failure of the solenoid valve.

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