초록 ▼

A fuel injection pump, capable of providing a preliminary fuel injection and a main fuel injection, includes a pump piston movable in a housing to define a pump working chamber which is connected with a fuel injection valve during the pumping stroke of the piston. The working chamber is relieved by

A fuel injection pump, capable of providing a preliminary fuel injection and a main fuel injection, includes a pump piston movable in a housing to define a pump working chamber which is connected with a fuel injection valve during the pumping stroke of the piston. The working chamber is relieved by the valve-closing member of the pressure valve. A magnetic valve which controls the function of the pressure-closing member is provided in the pump. An opening pressure of the pressure valve is greater than that of the fuel injection valve so that the preliminary injection is obtained with the initially open magnetic valve whereas the duration of the main fuel injection is controlled by the closed magnetic valve.

대표청구항 ▼

In a fuel injection pump for internal combustion engines, comprising housing means defining a pump working chamber; at least one pump piston movably guided in said working chamber; a fuel injection valve; means to connect said chamber to said fuel injection valve during an advancement stroke of said

In a fuel injection pump for internal combustion engines, comprising housing means defining a pump working chamber; at least one pump piston movably guided in said working chamber; a fuel injection valve; means to connect said chamber to said fuel injection valve during an advancement stroke of said pump piston to open or close said fuel injection valve, said housing means including a first unloading passage connected to said chamber, said housing means further including an unloading chamber connectable to said first unloading passage, and a second unloading passage connected to said unloading chamber to unload the latter; a controlling member controlling said first unloading passage to close or open the latter; a restoring spring positioned in said unloading chamber and biasing said controlling member in a direction of closing, the improvement comprising said first unloading passage having a valve seat with which said controlling member cooperates as a valve closing member, said controlling member being formed so that an opening pressure thereof is higher than the opening pressure of said fuel injection valve, said valve seat and said second unloading passage being connected with one another in an unthrottled manner; and a further valve operating so that in a first operating range said second unloading passage is open at the beginning of the advancement stroke of said pump piston by said further valve enabling a pre-injection of fuel, closed after opening of said controlling member for starting a main fuel injection and again opened for ending at the beginning of the advancement stroke of said pump piston for starting a fuel injection without preinjection and finally opened again for ending the fuel injection.