Fuel injection valve having a guide diaphragm and method for assembling

摘要

A fuel injection valve for an engine fuel injection system includes a valve housing, a valve seat fixedly secured to the valve housing and a valve needle movable axially and co-operably engageable with the valve seat. The fuel injection valve also includes a diaphragm that aligns the needle with the valve seat. The diaphragm has an outer zone attached to the housing and an inner zone attached to the needle, such that the inner zone of the diaphragm moves in unison with the needle to thereby avoid frictional sliding contact between the needle and the diaphragm. Alignment of the needle with the valve seat may be assured by assembly wherein the diaphragm is first fixed to the needle and the needle is then seated upon the valve seat prior to clamping of the outer zone of the diaphragm to the housing while the needle is seated.