Hydraulic control system for vehicular automatic transmission
US5269204A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 1992 |
| Grant date | Dec 14, 1993 |
| Priority date | — |
| Expiry date | Aug 17, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2059/006
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic control system for a vehicular automatic transmission includes a first servomotor, actuated by hydraulic pressure from a hydraulic pressure source, for engaging or releasing frictional engagement elements of the transmission; a second servomotor, actuated by the hydraulic pressure, for applying an engine brake; a manual valve and a shift valve, both connected between the hydraulic pressure source and the first and second servomotors, for controlling the hydraulic pressure; a cut-off valve interposed in a line extending between the manual valve and the shift valve; a solenoid valve for controlling the cut-off valve; and an electronic controller for receiving as inputs vehicular running conditions and a gear-shift mode and for outputting solenoid signals to control the shift valve and the cut-off valve responsive to the inputs. The controller outputs a solenoid signal to the cut-off valve to control communication between the manual valve and the shift valve through the line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.