Patent · US Expired

Control system for an automatic transmission

US5176046A · kind A · utility

3Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 28, 1991
Grant dateJan 5, 1993
Priority date
Expiry dateAug 28, 2011

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16H61/0206
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A control system for an automatic transmission has a shift gear mechanism with a plurality of frictional elements, including a low reverse brake which is selectively actuated for switching a power transmitting path to establish a desired shift stage. A hydraulic control circuit controls supply of a hydraulic fluid to and relief of the fluid from an actuator for the frictional element. An accumulator is provided in a hydraulic passage communicated with the low reverse brake for obviating a shock as the low reverse brake is engaged. Back pressure of the accumulator is controlled when a first shift gear stage is established through the engagement of the low reverse brake. A torque shock can be suppressed when the first stage is established in an L-range.

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