| 摘要 |
PROBLEM TO BE SOLVED: To reduce interference between a return spring and an inner diameter of a fixed iron core, reduce hysterisis, and improve accuracy of flow control by increasing an inner diameter of a bottomed hole as an installation part of the return spring of the fixed iron core from a bottom surface toward an opening end. SOLUTION: A return spring 9 arranged between a fixed iron core 2 and a movable iron core 3 is fitted to a bottomed hole on the fixed iron core 2 together with a spring holder 9a. The bottomed hole has a diameter so as to fix the spring holder 9a at its bottom, while its diameter is gradually increased toward an opening end so as to prepare a tapered form. The movable iron core 3 as a valve element is moved by carrying current to an electromagnetic coil 6 for varying an opening of a flow hole 4a formed on a guide cylinder 4. At this time, even when deformation such as variation in an outer diameter or deflection occurs at the return spring 9, its degree of force amount variation is extremely small which may be caused by rubbing between the outer diameter of the return spring 9 and an inner diameter of the bottom hole. An error of flow control to a current amount of the electromagnetic coil 6 and hysterisis are remarkably reduced. |
