Injection valve for fuel injection system for IC engine

摘要

It has control valve whose pressure determines position of metering valve shaft with valve push rod subjected to spring pressure. An injection valve for a fuel injection system for an IC engine has devices for multistage control of the effective cross- section of at least one injection opening (42). A valve pushrod allows a first axial stroke that is limited by a primary shoulder (37) on an axially moving intermediate piece (30). Its axial movability allows the valve push rod an additional second stroke against the pressure of a spring (31) which is limited by an end shoulder fixed in the housing. The valve is a control valve (4) for a control chamber (12) whose pressure determines the position of the valve shaft of a metering valve(1). The push rod is subjected to a first pressure spring tensioned against the housing of the injection valve in the closing direction of the control valve. The spring is constructed as a second pressure spring. In the closed state of the control valve, the spring force of the first pressure spring is much smaller than that of the second.