Method and apparatus for detecting a restricted or bypassed transmission oil filter
US6504474B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2000 |
| Grant date | Jan 7, 2003 |
| Priority date | — |
| Expiry date | Jan 30, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2705
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method and apparatus for detecting a restricted or bypassed transmission oil filter by providing pressure transducers on both sides of the oil filter whereby the pressure differential will indicate the extent of filter restriction. A first alarm is activated at a first pressure differential to indicate a restricted filter and the need for filter replacement. A second, higher level, alarm is activated to indicate the filter is bypassed and the engine is reduced in speed to allow the pressure and the pressure differential to drop to the point that the filter is no longer bypassed. This enables the vehicle to be operated with limited capabilities to allow the vehicle to be driven to the shop for filter replacement. If the lowered engine speed is insufficient to reduce the pressure differential to stop the bypass, then the engine speed is further reduced to a low idle and the transmission shifted to neutral. The filter must be replaced before the vehicle is can be operated again to prevent damage to the hydrostatic unit in the transmission.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.