Patent · US Expired

Hydraulic control unit for automatic transmission

US6634991B2 · kind B2 · utility

10Cited by
13References
12Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMay 8, 2001
Grant dateOct 21, 2003
Priority date
Expiry dateMay 8, 2021

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H2306/00
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic control unit including a hydraulic servo for engaging and disengaging each friction engagement element, hydraulic pressure supply device for supplying hydraulic pressure to a hydraulic servo of a predetermined friction engagement element selected according to a gearshift position to be achieved, failure detection device for detecting a failure has occurred in the hydraulic pressure supply device, and fail-safe device for preventing interlock that occurs due to a plurality of friction engagement elements being engaged, and also prevents a gearshift from a high-speed position to a low-speed position, when the failure detection device detects that a failure has occurred.

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