摘要:
A fuel supply system for a direct injection engine which has a variable capacity single cylinder plunger pump and two fuel rails. Offices are disposed at the upstream side inlets of both fuel rails, respectively. At the opposite sides to the inlet sides, the fuel rails are interconnected with each other by a connecting pipe. Using this fuel supply system, it is possible to increase a characterisitic frquency of the fuel columns, and to stabilize, suppress, and smooth out pressure pulsation in the fuel rails, thereby reducing uneven fuel injections into the cylinders. The system may have a cam which drives a plunger of a high pressure fuel pump to reciprocate once for every two combustions in two engine cylinders.
摘要:
The unevenness of injection rates of cylinders is reduced in a fuel supply system of a direct injection engine which uses a variable-displacement single plunger pump. The unevenness of injection rates of cylinders can be reduced by effecting a control such that the cam 100, which drives the high-pressure fuel pump 101, makes one reciprocation, while the engine makes explosions in two cylinders, and by causing the controller 55 to extend the injection time width of one of two injectors 54 which inject during one discharge of the high-pressure fuel pump and to shorten the injection time width of the other injector.
摘要:
In a fuel supply apparatus disclosed, a variable displacement mechanism is driven once every two or more reciprocating motions of the plunger of a high-pressure fuel pump to control the delivery flow rate, so that the delivery flow rate control can be performed without having to raise the responsiveness of the variable displacement mechanism even when the reciprocating cycle of the plunger is short.
摘要:
In order to provide a method for high volume and high pressure operation of a variable delivery type single cylinder plunger pump, the displacement of the piezoelectric element 20 is magnified by a hydraulic displacement magnifying mechanism comprising a large-diameter bellows 204, a small diameter bellows 202 and working fluid 208, and an engaging member 201 is displaced to control the time interval of opening and closing the intake valve 5. The large-diameter bellows 204 is used at all times in the state compressed in the direction of displacement transfer, thereby ensuring that the pressure of the working fluid 208 is maintained at a positive value to prevent vapor from being generated. The thermal expansion of a casing 23 is selected in such a way that the total thermal expansion of the piezoelectric element 200 and hydraulic displacement magnifying mechanism in the direction of displacement transfer is approximately the same as the thermal expansion of the casing 23, whereby highly efficient driving is provided.
摘要:
In a fuel pump pressurizing fuel and supplying the fuel to a fuel injection valve of a vehicle engine, a hardened layer of at least one selected from a nitride layer, a carburated and quenched layer and a carbonitrided layer, and a metal compound layer, on a surface of the hardened layer, higher in corrosion resistance than the hardened layer are formed on one of slide surfaces contacting each other and sliding in fuel.
摘要:
An intake valve automatically opened and closed by pressure of a pressuring chamber is provided in a fuel intake passage, the intake valve is pushed to open by a plunger of an electromagnetic plunger mechanism, pulling-in operating timing of the plunger is controlled according to the operating condition of an internal combustion engine, and opening time of the intake valve during compression stroke of a pump is controlled to make discharge flow-rate of high pressure fuel variable.
摘要:
An intake valve automatically opened and closed by pressure of a pressuring chamber is provided in a fuel intake passage, the intake valve is pushed to open by a plunger of an electromagnetic plunger mechanism, pulling-in operating timing of the plunger is controlled according to the operating condition of an internal combustion engine, and opening time of the intake valve during compression stroke of a pump is controlled to make discharge flow-rate of high pressure fuel variable.
摘要:
An intake valve automatically opened and closed by pressure of a pressuring chamber is provided in a fuel intake passage, the intake valve is pushed to open by a plunger of an electromagnetic plunger mechanism, pulling-in operating timing of the plunger is controlled according to the operating condition of an internal combustion engine, and opening time of the intake valve during compression stroke of a pump is controlled to make discharge flow-rate of high pressure fuel variable.
摘要:
A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.
摘要:
A controlling apparatus of a variable capacity type fuel pump, for preventing noises caused due to drive of the fuel pump and noises caused due to drive of injectors from overlapping or duplicating each other in the timing thereof, wherein signals for driving the pump are reduced, or the timing thereof is shifted forward/backward, within a specific timing where the overlapping can be expected, or a specific timing where they are determined to overlap or duplicate with each other.