Patent · US Expired

Hydraulic control system for automatic transmission of multiple clutch type which prevents two clutches from being simultaneously engaged

US6055879A · kind A · utility

15Cited by
7References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 9, 1997
Grant dateMay 2, 2000
Priority date
Expiry dateApr 9, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T74/19251
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic control system for an automatic transmission of multiple clutch type, in which a switchover valve (2 in FIG. 4) for switching-over clutch control pressures includes two spool valvules (4 and 6). When one of two clutches (C1 and C2) is supplied with the clutch control pressure and is held in engagement, the spool valvules (4 and 6) operate to cut off the supply of the clutch control pressure for the other clutch to-be-disengaged and to hold the engagement of one clutch to-be-engaged. Thus, even when the supply source (12 or 14) of the clutch control pressure has failed, the clutches (C1 and C2) are prevented from coming into multiple engagement.

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