Abstract: A magnetic actuator includes a first yoke, an armature which is provided inside the first yoke and made movable in reciprocating motion along a first direction inside the first yoke, first and second coils fitted inside the first yoke, a pair of second yokes affixed to the first yoke along a second direction, and permanent magnets affixed to the second yokes in a manner that the permanent magnets are positioned face to face with the armature. In the magnetic actuator thus constructed, fluxes generated by the first and second coils pass through first magnetic circuits whereas fluxes generated by the permanent magnets pass through second magnetic circuits differing from the first magnetic circuits.

Abstract: In an actuator, coils are kept from being displaced along a y-axis direction as projections of coil bobbins are sandwiched between first and second iron cores along the y-axis direction. Also, the coils are kept from being displaced excessively along x- and z-axis directions due to shocks, for instance, because they are fitted in groovelike channels fitted in the first and second iron cores. Since two bearings are sandwiched and fixed between third and fourth iron cores along the x-axis direction, the bearings can be easily set on a common axis with high accuracy. It is therefore possible to prevent displacement of the coils during operation of the actuator. Slidable support plates ensure smooth movements of an armature and thereby provide improved reliability, even when the distance between the support plates and the first to fourth iron cores is reduced.

Abstract: A magnetic actuator includes a first yoke, an armature which is provided inside the first yoke and made movable in reciprocating motion along a first direction inside the first yoke, first and second coils fitted inside the first yoke, a pair of second yokes affixed to the first yoke along a second direction, and permanent magnets affixed to the second yokes in a manner that the permanent magnets are positioned face to face with the armature. In the magnetic actuator thus constructed, fluxes generated by the first and second coils pass through first magnetic circuits whereas fluxes generated by the permanent magnets pass through second magnetic circuits differing from the first magnetic circuits.

Abstract: In an operation circuit of an electromagnetic switching device, when electric energy is discharged by discharge switches connected in series, respectively, to opening coils and closing coils, an induction current flowing in a direction opposite to a current of the coil of the excitation side is generated. The current flows through the coil on the non-excitation side due to magnetic coupling, and a magnetic flux necessary for driving is cancelled, thereby inhibiting generation of a driving force. The operation circuit includes first and second opening and closing coils, so that a moving element may be driven between those coils. This circuit includes a circuit for suppressing an over-voltage at the moment of interrupting an excitation current of a first coil and for interrupting an induction current generated through the first coil at the time of exciting the second coil.

Abstract: In an operation circuit of an electromagnetic switching device when electric energy is discharged by discharge switches connected in series, respectively, to opening coils and closing coils, an induction current flowing in a direction opposite to a current of the coil of the excitation side is generated. The current flows through the coil on the non-excitation side due to magnetic coupling, and a magnetic flux necessary for driving is cancelled, thereby inhibiting generation of a driving force. The operation circuit includes first and second opening and closing coils, so that a moving element may be driven between those coils. This circuit, includes a circuit for suppressing an over-voltage at the moment of interrupting an excitation current of a first coil and for interrupting an induction current generated through the first coil at the time of exciting the second coil.

Abstract: In an actuator of the invention, coils are kept from being displaced along a y-axis direction as projections of coil bobbins are sandwiched between first and second iron cores along the y-axis direction. Also, the coils are kept from being displaced excessively along x- and z-axis directions due to shocks, for instance, as they are fitted in groovelike channels formed in the first and second iron cores. Since two bearings are sandwiched and fixed between third and fourth iron cores along the x-axis direction, the bearings can be easily set on a common axis with high accuracy. It is therefore possible to prevent displacement of the coils during operation of the actuator. Slidable support plates ensure smooth movements of an armature and thereby provide improved reliability even when the distance between the support plates and the first to fourth iron cores is reduced.

Abstract: A switching apparatus for multiphase electric power includes switching units corresponding to different phases. Each switching unit includes an operating mechanism having a movable coil disposed between two fixed coils, and a switch portion having a movable contact operatively connected to the movable coil. A separate power supply may be provided for each switching unit to permit individual control of the different phases.

Abstract: A switching device includes a pair of fixed coils and a pair of movable coils, with one pair being disposed between the other pair. Two of the coils may be connected back to back on opposite sides of a support plate to increase the stiffness of the coils and reduce damage due to impact between the fixed and movable coils. The coils include two sets of coils, each set including one of the fixed coils and one of the movable coils. The coil sets can be driven simultaneously or at different times to effect contact opening and closing.

Abstract: A switching device includes a movable coil which is reinforced by a stiffener to increase the resistance of the movable coil to bending moments. The stiffener may include a nonmagnetic case which surrounds the movable coil. Alternatively or in addition, it may include a resin or other material encapsulating the movable coil.

Abstract: The circuit breaker includes a stationary contact member having a stationary contact, a movable contact member having at one end a movable contact contacting and separating from the stationary contact and having at the other end a rotational center, a case surrounding the stationary contact and the movable contact and defining a pressure accumulating space at one side of an arc generation position at which an electric arc is generated for temporarily storing a pressurized gas pressurized by the arc generated between the stationary and the movable contact upon a current interruption, and an exhaust port disposed at the other end of the arc generation position in the case so that the pressurized gas stored within the accumulation space upon the current interruption is exhausted by passing between the stationary contact and the movable contact.

Abstract: A switching apparatus includes a pair of fixed coils and a pair of movable coils, with one pair being disposed between the other pair. Two of the coils may be connected back to back on opposite sides of a support plate to increase the stiffness of the coils and reduce damage due to impact between the fixed and movable coils. The coils include two sets of coils, each including one of the fixed coils and one of the movable coils. The coil sets can be driven simultaneously or at different times to perform contact opening and closing operation.

Abstract: A switching device includes a movable coil which is reinforced by a stiffener to increase the resistance of the movable coil to bending moments. The stiffener may include a nonmagnetic case which surrounds the movable coil. Alternatively or in addition, it may include a resin or other material encapsulating the movable coil.

Abstract: A switching apparatus for multiphase electric power includes a plurality of switching units corresponding to different phases. Each switching unit includes an operating mechanism having a movable coil disposed between two fixed coils, and a switch portion having a movable contact operatively connected to the movable coil. A separate power supply may be provided for each switching unit to permit individual control of the different phases.

Abstract: A current limiting device includes first and second contact members, each contact member having, at a first end, contacts defining a contact pair; a contacting pressure is applied to said contact pair; and a cylindrical insulator cylindrically surrounding the contacts when the contacts are closed. The device is arranged such that at least one of the first and second contact members is rotatably supported at a second end. Also, an electrical path is defined through which currents flow in substantial opposition to the first and second contact members and in opposite directions to each other. The first ends of the first and second contact members are positioned within the space defined by the cylindrical insulator in the closed contact state. The contact of at least one of the rotatably supported contact members is positioned outside of the space defined by the cylindrical insulator when the contacts are open.