Automatic transmission control system having a neutral idle feature
US6171211A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 1999 |
| Grant date | Jan 9, 2001 |
| Priority date | — |
| Expiry date | Oct 1, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H61/143
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An electronically controlled automatic transmission hydraulic valve system for an automotive vehicle transmission having multiple forward-drive ratios and a reverse ratio. Clutch and brake means controls motion of gearing elements for establishing forward torque flow paths and a reverse torque flow path, the clutch and brake means including a reverse drive clutch and a forward drive clutch. Each clutch, when engaged, completes a torque flow path from a vehicle engine to torque input elements of the gearing. The forward clutch and reverse clutch each includes friction elements that are frictionally engaged by a pressure-actuated piston. Regulated pressure strokes each piston. An engagement valve system triggers normal forward clutch and reverse clutch operation during torque delivery and for establishing a neutral idle capability in both forward and reverse.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.