| 摘要 |
The invention provides an electromagnetic driven type fuel injection valve employing an electromagnetic coil spring for a valve closing spring, which can achieve an accurate valve function over a long period of time while making interference between members caused by the valve closing spring to the minimum. In an electromagnetically driven type fuel injection valve in which a stopper core is arranged so as to be fitted and inserted in a through hole of an electromagnetic coil case, a plunger slidably arranged on the same center line as the stopper core has a needle insertion hole pierced from the proximal end surface, a leading end portion of a needle is inserted in the needle insertion hole, and an electromagnetic coil-shaped valve closing spring arranged in compression and having proximal end side wound around an approximately columnar spring retaining portion provided in a protruding manner on the needle leading end surface urges the plunger so that the valve closing spring closes the valve when the electromagnetic coil is not excited, and attracts the plunger to the stopper core so as to open the valve when the electromagnetic coil is excited. The valve closing spring has a proximal end portion which is not elastically deformed and a center portion which is elastically deformed, the proximal end portion having a diameter smaller than that of the center portion, the proximal end portion being wound around the spring retaining portion in close contact therewith has a proximal end portion which is not elastically deformed.
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