Internal-combustion engines – Charge forming device – With fuel pump
Reexamination Certificate
1997-08-29
2001-05-01
Miller, Carl S. (Department: 3747)
Internal-combustion engines
Charge forming device
With fuel pump
C123S456000
Reexamination Certificate
active
06223731
ABSTRACT:
CROSS REFERENCE TO RELATED APPLICATION
This application is related to and incorporates herein by reference Japanese patent Applications No. 8-237567 filed on Sep. 9, 1996, No. 9-29934 filed on Feb. 14, 1997 and No. 9-105482 filed on Apr. 23, 1997.
BACKGROUND OF THE INVENTION
1. Field of the Invention:
The present invention relates to adjusting the fuel pressure supplied to an internal combustion engine by controlling a fuel pump.
2. Description of Related Art:
A returnless piping structure having no fuel return to the fuel tank for surplus fuel fed to an engine fuel injector has been employed to simplify the fuel conduit and thus realize a reduction in size and cost. In this case, as described in Japanese Patent Application Laid-open No. 6-147047, a fuel pressure sensor detects piping system pressure and provide a voltage to a built-in fuel pump motor that is controlled through a feedback loop so that fuel pressure matches the target fuel pressure.
However, in this system, since the amount of fuel discharged from the fuel pump increases after the amount of fuel consumed in the engine increases, for example, during a transition period (engine acceleration) where the amount of fuel injected from the injector increases quickly, fuel pressure is temporarily lowered due to delay in both control response and fuel transfer. On the contrary, when the amount of fuel discharged from the fuel pump is reduced after the amount of fuel consumed in the engine is decreased during a transition period (engine deceleration) where the amount of fuel injection reduces quickly, fuel pressure is temporarily increased due to delayed control responses. Such variation of fuel pressure causes deviation of the air-fuel ratio supplied to the internal combustion engine and thus also results in deterioration of exhaust emission and drivability.
In order to avoid such drawbacks, it is proposed that such delay of transition responses be compensated by detecting the rate of transitional variation of the requested amount of fuel injection and then calculating with mapped data stored in a memory an appropriate compensating value depending on such rate of transitional variation.
However, the system has a disadvantage in that the arithmetic operations required are rather complicated and a large amount of memory capacity is required because it is required, as explained above, to detect a rate of transitional variation of the requested amount of fuel injection and to calculate with the mapped data the compensating value depending on such a rate of transitional variation.
SUMMARY OF THE INVENTION
The present invention provides a fuel feeding apparatus for internal combustion engine which can improve fuel pressure control in the transitional period with rather simplified arithmetic operations or with hardware of simplified structure.
According to a first aspect of the present invention, the compensation amount corresponding to a response delay of the fuel feeding system generated in the transitional operation of an internal combustion engine is calculated using a fuel transfer model from the fuel tank to an injector. A fuel pump is driven on the basis of the basic control amount and the amount of control calculated on the basis of the compensation amount for response delay so that transitional response delay in control and fuel transfer may be suppressed and thereby resultant variation of fuel pressure during the transitional period can also be controlled. Thus, it is no longer required to detect the rate of transitional variation of the requested amount of fuel injection because the compensation amount for delay of response is calculated using a fuel transfer model.
According to a second aspect of the present invention, the compensation is calculated on the basis of the difference between a first-order delay in the amount of fuel injection and the actual amount of fuel injection of the fuel injector. That is, as the variation in the amount of fuel injection changes more quickly, the difference between the first-order delay in the amount of fuel injection and the actual amount of fuel injection becomes larger, and adequate delay compensation can be calculated depending on the rate of transitional variation in the amount of fuel injection. In this case, the difference between the primary delay in the amount of fuel injection and the actual amount of fuel injection can be obtained with simplified arithmetic operations or hardware of simplified structure, resulting in simplified arithmetic operations.
According to a third aspect of the present invention, a delay compensation is calculated depending on the amount of variation of the amount of fuel injection of the fuel injector. That is, since variation in the amount of fuel injection causes variation of fuel pressure, adequate delay compensation can be calculated depending on the rate of transitional variation of fuel injection by calculating of compensation delay on the basis of the variation of the amount of fuel injection. In this case, variation of the amount of fuel injection can also be obtained with simplified arithmetic operations or hardware of simplified structure, resulting in simplified arithmetic operations for the delay compensation.
REFERENCES:
patent: Re. 33270 (1990-07-01), Beck et al.
patent: 4359984 (1982-11-01), Nakao
patent: 4526151 (1985-07-01), Tateishi
patent: 4660524 (1987-04-01), Bertsch
patent: 4800859 (1989-01-01), Sagisaka et al.
patent: 5211150 (1993-05-01), Anzai
patent: 5215062 (1993-06-01), Asano et al.
patent: 5355859 (1994-10-01), Weber
patent: 5361742 (1994-11-01), Briggs et al.
patent: 5365906 (1994-11-01), Deweerdt
patent: 5367999 (1994-11-01), King et al.
patent: 5377645 (1995-01-01), Moore
patent: 5379741 (1995-01-01), Matysiewicz
patent: 5398655 (1995-03-01), Tuckey
patent: 5406922 (1995-04-01), Tuckey
patent: 5421306 (1995-06-01), Talaski
patent: 5429094 (1995-07-01), Akiba
patent: 5448977 (1995-09-01), Smith et al.
patent: 5477829 (1995-12-01), Hassinger et al.
patent: 5483940 (1996-01-01), Namba et al.
patent: 5499608 (1996-03-01), Meister
patent: 5546911 (1996-08-01), Iwamoto et al.
patent: 5586539 (1996-12-01), Yonekawa et al.
patent: 5715797 (1998-02-01), Minagawa
patent: 5749344 (1998-05-01), Yoshiume
patent: 5752486 (1998-05-01), Nakashima
patent: 57-68529 (1982-04-01), None
patent: 4-63929 (1992-02-01), None
patent: 6-147047 (1994-05-01), None
patent: 6-173805 (1994-06-01), None
patent: 7-1374 (1995-01-01), None
patent: 7-27029 (1995-01-01), None
Isomura Shigenori
Yoshiume Naoki
Denso Corporation
Miller Carl S.
Nixon & Vanderhye
LandOfFree
Fuel feeding apparatus with response delay compensation does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fuel feeding apparatus with response delay compensation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuel feeding apparatus with response delay compensation will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2527849