Diagnostic system for canister purge system
US5191870A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 2, 1991 |
| Grant date | Mar 9, 1993 |
| Priority date | — |
| Expiry date | Oct 2, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M2025/0845
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An on-board diagnostic system determines if there is a leak in the portion of a canister purge system that includes the fuel tank and the canister that collects volatile fuel vapors from the fuel tank's headspace. A vacuum regulator/sensor placed in the conduit between the CPS valve and the canister, includes a switch providing a signal indicating the presence or absence of a leak. The sensor also indicates both positive and negative pressures relative to a reference pressure such as atmosphere. During diagnostic testing, the switch is closed and if the switch becomes open this indicates a leak in the headspace of fuel tank on the canister.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.