摘要:
Disclosed is a fuel injection quantity control system incorporated with a fuel injection pump with a solenoid-operated spill valve wherein a control signal is generated for cutting off a fuel supply to engine cylinders when a rotational phase angle of a drive shaft of the fuel injection pump is coincident with a desired spill phase angle determined in accordance with engine operating conditions. The desired spill phase angle, i.e., the opening timing of the spill valve is controlled in accordance with the rotational variations of the fuel injection pump. The desired spill phase angle is divided by unit angle corresponding to a detection period of rotational angle signals produced in accordance with the rotation of the pump drive shaft, obtaining a quotient and a remainder angle. The remainder angle is converted into a time on the basis of an engine speed. The generation of the control signal basically occurs upon the elapse of the converted time after the count of rotational angle signals is coincident with the quotient. If the engine operating condition varies immediately prior to the coincidence therebetween, the control signal is generated immediately after the coincidence or upon the elapse of a predetermined time period thereafter.
摘要:
A fuel injection pump is described wherein a plunger is rotatingly and reciprocally movable in an enclosure to define a compression chamber which is connected to a fuel inlet during an intake stroke of the plunger and to a fuel outlet during a compression stroke thereby to initiate injection of fuel to the outlet. A solenoid valve is responsive to a voltage applied from a voltage source for providing a pressure relief action on the fuel in the compression chamber. A control unit is responsive to the onset of fuel injection to determine a basic timing at which fuel is to be terminated and corrects the basic timing as a function of the source voltage to compensate for a voltage variation thereof which would otherwise affect on the operation of the solenoid valve. The solenoid valve is then energized at the corrected timing.
摘要:
A fuel injection pump of the distribution type is provided with an electromagnetic valve for escaping the fuel in the pump chamber of the fuel injection pump. The fuel injection pump is also provided with a sensor for detecting the rotary angle of a pump shaft. This sensor is attached to a roller ring of a converter mechanism which also comprises a face cam, for example, and which also serves to convert the rotation of the pump shaft the reciprocate with that of a pump plunger. The sensor generates signals which represent the rotary angles of the pump shaft. The operation of the electromagnetic valve is controlled to escape the fuel in the pump chamber, depending upon the signals supplied from the sensor.
摘要:
A high-pressure fluid control solenoid valve assembly for use with a spill type fuel injection pump of an internal combustion engine, comprises an actuator portion (101) including a solenoid (8, 9), a stator (7) and an armature (14), and a valve portion (102) including a pilot valve (40, 41) and a main valve (42, 43) where the valve portion (102) is spaced apart from the actuator portion (101) and is responsive to the movement of the armature (14) via a rod (14) connected to the armature (14) and extends axially in a bore of the stator (7) which is cylindrical hollow. The pilot valve (40, 41) is coaxial with and telescopically received in the main valve (42, 43) so that two fluid chambers (54, 51) are formed inside and outside, respectively a spool (42) of the main valve such that the main valve is continuously kept closed irrespective of the fluid pressure in these chambers as long as the pilot valve is closed. The pilot valve comprises a needle (40) which is arranged to be pressed by the rod (13) to close the pilot valve on energization of the solenoid (8, 9), where the needle (40) is normally biased in valve-opening direction. On deenergization, the pilot valve opens causing the main valve to spill fuel thus terminating the fuel injection.
摘要:
In a fuel injection control system for multi-cylinder internal combustion engines, the speed of the engine is monitored and sampled at predetermined angular intervals of engine revolution to detect instantaneous engine speed values identifiable by individual cylinders. From the successively detected instantaneous speeds is derived an average value which is used as a reference for the instantaneous speed values to detect their deviations therefrom. Cylinder-to-cylinder variations in engine speed are minimized by metering the fuel according to the individually derived engine speed deviations.
摘要:
A variable discharge high pressure pump for pumping a fuel into a common rail of a common rail type fuel injection system has a plunger reciprocable in a cylinder bore and a pumping chamber defined between and end face of the plunger and the inner peripheral surface of the cylinder bore. A solenoid valve has a valve member movable into an open position in which the valve member is moved out of engagement with an associated value seat into the pumping chamber when the solenoid valve is deenergized. When the solenoid valve is energized, the valve member is moved into a closed position in which the fuel pressure in the pumping chamber acts on the valve member to urge the same into engagement with the valve seat. The plunger is of a simple cylindrical structure free from any lead formed therein.
摘要:
A fuel injection system for a diesel engine has fuel pump driven by the engine for producing highly pressurized fuel, a common rail for storing the pressurized fuel therein and injection nozzles for injecting the pressurized fuel stored in the common rail into the engine. The injection nozzles are electrically controlled in accordance with engine operating conditions (N, .alpha.) by the use of injection control solenoid valves provided between the injection nozzles and the common rail. The fuel pump is electrically controlled in accordance with the engine operating conditions by the use of a spill control solenoid valve which spills the pressurized fuel to a low pressure fuel channel so that loss of engine torque required by the pump is reduced.
摘要:
Disclosed is a solenoid valve assembly for use in an fuel injection pump of a motor vehicle basically comprising an electromagnetic actuator section including a stator, a core and a winding and a valve section having a valve for interrupting flow of fuel in a fuel passage. A rod-like member is coupled between the valve and the core and is movable within a guide hole made at the center of the stator so that the movement of the core is transmitted to the valve. The valve is biased by a spring in a direction closing the fuel passage. The valve is actuated to open the fuel passage in response to energization of the winding and is actuated to close the fuel passage in response to deenergization of the winding, the opening degree of the valve being regulated and adjusted by a stopper. The spring and the stopper is provided at a high pressure side of the fuel passage communicating with a compression chamber of the fuel injection pump.
摘要:
In controlling a fuel injection quantity by spilling a part of fuel fed from a high pressure chamber of a fuel injection pump using a high pressure electromagnetic valve which is on-off controlled by a driving circuit in accordance with engine operating conditions, switch means is provided between the high pressure electromagnetic valve and a power source, an output signal from the driving circuit is monitored, and the switch means is opened when the output signal from the driving circuit continues more than a predetermined period.
摘要:
A fuel injection pump according to the present invention is provided with a spill passage and an escape passage which are connected to a pump chamber. Disposed in the middle of the spill passage is a solenoid valve, which is adapted to open the spill passage to spill fuel in the pump chamber to the low-pressure side at predetermined times while the fuel in the pump chamber is pressurized by a pump plunger, thereby adjusting the delivery of compressed fuel from the fuel injection pump. The escape passage is formed in the pump plunger so as to be coaxial therewith. One end of the escape passage communicates with the pump chamber, while the other end opens to the outer peripheral surface of the pump plunger. An escape ring is fitted on the outer peripheral surface of the pump plunger, whereby the opening of the escape passage is opened when the pump plunger reaches a predetermined compression stroke.