Hydraulic temperature compensated cooler bypass control for an automatic transmission
US5890509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1997 |
| Grant date | Apr 6, 1999 |
| Priority date | — |
| Expiry date | Mar 31, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2642
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A cooler bypass valve, located in a hydraulic circuit between the discharge side of a torque converter and lubrication circuit, includes a valve spool urged by feedback pressure acting in opposition to the force of a compression spring to a bypass cooling mode position where the converter discharge fluid flow is connected to the lubrication circuit bypassing the oil cooler. The bypass valve includes a viscosity-sensitive pressure divider, which includes a series arrangement of a laminar orifice and a sharp-edged orifice located between the converter discharge and an oil sump. As oil temperature increases, flow through the laminar orifice produces a control pressure in opposition to the feedback pressure and additive to a spring force, which combine to move the valve spool to a cooling mode position where substantially all of the converter discharge is directed through the oil cooler. In a predetermined temperature range, the valve maintains a position where a portion of the converter discharge is directed to the oil cooler, and the residual to the lubrication circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.