Abstract: A plunger type electromagnet is provided with an attractive plate connected to the plunger, with an improved configuration of plunger and stationary element, or with a flanged tubular member of magnetic material affixed to the axial end of a coiling bobbin, in order to increase the rate of change in the permeance of the magnetic circuit at the time of attractive operation and to enhance the sensitivity of the electromagnet.Furthermore, the surface area of the abutment faces of the stationary and movable elements is calibrated so as to control the attractive and retaining force thereof.In some embodiments, a permanent magnet is provided which is shaped in the form of an annulus and is magnetized in the direction of thickness of the annulus, so as to facilitate magnetization of the permanent magnet, to reduce the number of component parts, and to provide an electromagnet which is compact in size, light in weight, and suitable for mass production.

Abstract: There are provided a valve which is opened by an improved two-step motion, a valve which operates positively without leakage of fluid even when the difference in pressure between inlet and outlet of the valve is very small, and an improvement of a solenoid valve using those valves.The present invention relates to small-sized opening/closing valve and solenoid valve capable of being operated by very small force and electric power using a dry cell or the like, and is suitable to a solenoid valve for automatic opening/closing control which is used in city gas appliances, etc.

Abstract: An operation confirming device for electromagnetic actuator according to the present invention is applied to an electromagnetic actuator comprising a stationary core, a movable core facingly arranged with respect to the stationary core so that the movable core can be moved close to or apart from the stationary core and formed in a closed magnetic circuit together with the stationary core, and an electric coil wound around the closed magnetic circuit. This operation confirming device is provided with a movable core shift detector for detecting time when shift operation of the movable core with respect to the stationary core by applying DC current to the electric coil is completed, by means of transitional fluctuating wave of the applied DC current. This operation confirming device is simply constructed, so that it can be formed in a compact size and a light weight with low manufacturing cost, and the reliability of operation confirming for electromagnetic actuator can be improved.

Abstract: The present invention provides an improvement for noise suppression, in an electromagnet constructed of the parts including a yoke, a fixed iron core fixed relative to the yoke, a movable iron core capable of being attracted toward and coming apart from the fixed iron core and a coiled wire wound around the magnetic path formed of the yoke, fixed iron core and movable iron core which serves to attract the movable iron core toward the fixed iron core by means of the magnetic flux induced by passing an electric current therethrough, which comprises dividing either one of the fixed iron core and the movable iron core into a body member and an end-surface member, at which the fixed and movable iron cores are contacted with each other, providing an elastic insert member between the body member and the end-surface member of the iron core in such a manner as not to interrupt the path of the magnetic flux and, optionally, providing a spring means which urges a stem supporting the end-surface member in such a manner t

Abstract: This invention relates an electronic locking device that may be operated manually and by key input, selectively, depending upon the various circumstances. In the locking condition, a hole is provided on an unlocking member and a hole is provided in a retaining mechanism, and the holes are aligned to allow the insertion of a moving piece into the both holes; and at unlocking, both of the holes are misaligned to prevent the insertion of the moving piece into either of the two holes.