Internal-combustion engines – Charge forming device – Fuel injection system
Patent
1998-10-06
2000-07-11
Miller, Carl S.
Internal-combustion engines
Charge forming device
Fuel injection system
123456, F02M 700
Patent
active
060857277
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to a fuel injection method and apparatus for an engine both of which inject fuel into combustion chambers from injectors by using the pressure of working fluid pressurized by a pump and stored in an accumulator.
BACKGROUND ART
Regarding fuel injection control for an engine, an accumulator fuel injection system is known as a method of increasing injection pressure and optimally controlling injection conditions such as fuel injection timing and fuel injection quantity according to the operating state of the engine. The accumulator fuel injection system is a system which stores in an accumulator a working fluid for fuel injection control pressurized at a predetermined pressure by a pump and injects fuel into combustion chambers from the corresponding injectors by using the pressure of the working fluid. In the accumulator fuel injection system, a controller controls the pressure of the accumulator and control valves provided in the respective injectors so that the pressurized fuel can be injected from the injectors under injection conditions optimum for the operating state of the engine.
Conventionally, two types of accumulator fuel injection systems are known. One type of accumulator fuel injection system is a system which uses a high-pressure working oil different from fuel as its working oil. In this system, the high-pressure working oil is stored in a high-pressure oil manifold which serves as an accumulator, and pressure intensifying pistons are driven by using the pressure of the working oil to intensify the pressure of the fuel on the basis of the ratio of a larger area at one end of each of the pressure intensifying pistons which are exposed to a pressure chamber into which to introduce the high-pressure working oil to a smaller area at the other end of each of the pressure intensifying pistons which are exposed to pressure intensifying chambers into which to introduce the fuel, and the pressure-intensified fuel is injected into combustion chambers from injection holes formed in the tip ends of the respective injectors.
This type of accumulator fuel injection system will be described below with reference to FIGS. 9 and 10. In a fuel supply system in the engine shown in FIG. 9, fuel is supplied to an injector 1 of each cylinder of the engine from a common rail 51 which is a common passage for fuel supply. Fuel in a fuel tank 52 is supplied to the common rail 51 through a fuel filter 54 by the driving of a fuel pump 53. The injector 1 communicates with the common rail 51 through a fuel supply port 11 and a fuel discharge port 12, and an extra fuel is returned to the fuel tank 52 through a fuel return passage 55.
A high-pressure working fluid which differs in line from fuel, i.e., working oil, is supplied to each of the injectors 1 to intensify fuel pressure. That is to say, the injectors 1 are connected to a high-pressure manifold 5 which serves as a common accumulator. Oil in an oil reservoir 57 is fed out to an oil supply passage 61 by the operation of an oil pump 58. An oil cooler 59 and an oil filter 60 are provided halfway along the oil supply passage 61. The oil supply passage 61 branches into a lubrication system passage 67 which leads to an oil gallery 62 and a working oil system passage 66 connected to a high-pressure oil pump 63. The supply of oil to a high-pressure oil manifold 56 from the high-pressure oil pump 63 provided at the working oil system passage 66, that is, the oil pressure in the high-pressure oil manifold 56, is controlled by a flow control valve 64. An extra oil is returned to the oil reservoir 57 through an oil return passage 65. A controller 50 is arranged to execute control of the flow control valve 64 and control of solenoids 10 of the respective injectors 1. An engine speed Ne detected by an engine-speed sensor 68, a depression quantity of an accelerator pedal detected by an accelerator depression quantity sensor 69, that is, an accelerator depression quantity Acc, and a crank angle detected by a crank angle sensor 70 are inputte
REFERENCES:
patent: 4884545 (1989-12-01), Mathis
patent: 5176115 (1993-01-01), Campion
patent: 5176120 (1993-01-01), Takahashi
patent: 5176122 (1993-01-01), Ito
patent: 5697343 (1997-12-01), Isozumi
patent: 5711274 (1998-01-01), Drummer
patent: 5713326 (1998-02-01), Huber
patent: 5896841 (1999-04-01), Nemoto
Isuzu Motors Limited
Miller Carl S.
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