Internal-combustion engines – Charge forming device – Fuel injection system
Reexamination Certificate
1999-09-15
2001-02-27
Argenbright, Terry M. (Department: 3747)
Internal-combustion engines
Charge forming device
Fuel injection system
C073S118040
Reexamination Certificate
active
06192866
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to technique for detecting a freezing or icing condition of an intake pressure sensor.
The intake manifold pressure of an engine is often used as one of main input signals in fuel injection control systems such as a electronic fuel injection system of a D-Jetronic type. An intake pressure sensor is attached to an intake passage downstream of a throttle valve.
SUMMARY OF THE INVENTION
In cold weather, water droplets may freeze and disable an intake pressure sensor in an engine cold start operation. Such freezing condition can take place in a pressure introduction pipe for introducing an intake pressure to an intake pressure sensor, or a sensing section of an intake pressure sensor directly attached to an intake passage. The freezing condition can deprive the fuel injection system of the correct input information on the intake pressure needed to perform the normal fuel injection control.
It is therefore an object of the present invention to provide a diagnostic system or method for accurately detecting a freezing condition of an intake pressure sensor.
According to the present invention, a diagnostic apparatus for detecting a freezing condition of an intake pressure sensor for sensing a pressure in an intake passage of an internal combustion engine comprises discriminating means and diagnosing means. The discriminating means is for monitoring an engine operating condition in an engine starting operation to determine whether a predetermined requirement for permitting a freeze diagnosis is satisfied. The diagnosing means is for examining an output signal of the intake pressure sensor to detect the existence or nonexistence of the freezing condition of the intake pressure sensor when the predetermined requirement is satisfied.
REFERENCES:
patent: 5349936 (1994-09-01), Uchinami
patent: 5635633 (1997-06-01), Kadota
patent: 5808189 (1998-09-01), Toyoda
patent: 6035835 (2000-03-01), Shigihama et al.
patent: 62-233447 (1987-10-01), None
patent: 6-167236 (1994-06-01), None
Araki Akihiko
Fujimoto Michiyuki
Miyata Mitsuru
Ohsaki Masanobu
Argenbright Terry M.
Foley & Lardner
Unisia Jecs Corporation
LandOfFree
Diagnosis for detecting freezing condition in intake... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Diagnosis for detecting freezing condition in intake..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Diagnosis for detecting freezing condition in intake... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2577116