Evaporative emission leak detection system

Details Evaporative emission leak detection system Evaporative emission leak detection system

1997-03-26

1998-10-06

Williams, Hezron E.

Measuring and testing

With fluid pressure

Leakage

73 497, 123520, F02M 3704, G01M 320

Patent

active

058179259

ABSTRACT:
An on-board diagnostic system for an evaporative emission control system of an internal combustion engine powered vehicle employs a leak detection module that is fluid connected in a vent passage for the evaporative emission space. The leak detection module contains an electric motor driven impeller, a solenoid operated valve assembly that is selectively operable to three positions, and a pressure-responsive switch whose switching characteristic possesses hysteresis corresponding to an upper regulating limit and a lower regulating limit. The valve assembly operates to allow the prime mover to pump gaseous fluid with respect to the evaporative emission space to attain a test pressure in the evaporative emission space corresponding to the upper regulating limit, to close the evaporative emission space and prevent the prime mover from pumping gaseous fluid with respect to the evaporative emission space upon initially attaining the upper regulating limit test pressure within the evaporative emission space, and which allows the prime mover to pump gaseous fluid with respect to the evaporative emission space at a pre-defined volumetric flow rate to rebuild pressure in the evaporative emission space to the upper regulating limit when the pressure has changed to the lower regulating limit due to a leak in the evaporative emission space.

REFERENCES:
patent: 5146902 (1992-09-01), Cook et al.
patent: 5297529 (1994-03-01), Cook et al.
patent: 5383437 (1995-01-01), Cook et al.
patent: 5390645 (1995-02-01), Cook et al.
patent: 5411004 (1995-05-01), Busato et al.
patent: 5474050 (1995-12-01), Cook et al.
patent: 5483942 (1996-01-01), Perry et al.
patent: 5499614 (1996-03-01), Busato et al.
patent: 5606121 (1997-02-01), Blomquist et al.
patent: 5635630 (1997-06-01), Dawson et al.
patent: 5651350 (1997-07-01), Blomquist et al.
patent: 5685279 (1997-11-01), Blomquist et al.

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