Abstract: The electromagnetic actuator has fixed and movable electromagnets. Each of both electromagnets has a plurality of slots formed in a substantially flat plane of a core member, and coil elements disposed in each slot so that directions of current in each slot are reversed alternately. The fixed and movable electromagnets are housed in a housing, with the respective slot-formed planes facing each other. Both electromagnets are excited at the same time, and resultant magnetic attraction or repulsion between both electromagnets causes the movable magnet to move. The movement of the movable magnet is derived by pickup means. By means of the utilization of attraction and repulsion between the electromagnets, a high speed operation can be achieved.

Abstract: An improved bi-stable electromagnetic actuator is provided having an armature linkage moveable between two stable positions either manually or through the application of an appropriate electrical pulse. The actuator includes a permanent magnet which maintains the actuator armature in a first stable position. It also includes a coil which reduces the magnetic flux used to restrain the armature and allows a compression spring to advance the armature to a second stabled position. In moving from the first to the second positions, the armature engages a stop on the linkage and drives the linkage in the same direction. The linkage, thus, transmits the mechanical action of the armature. The user may manually advance the linkage from the first to the second stable position. This linkage includes a rod of magnetically impermeable material in sliding engagement with the armature and a sleeve disposed around this rod at one end of the rod. This sleeve is made from soft magnetic material.

Abstract: A polarized relay comprises a bar-like core having coil, and a yoke connected to the core and extending in parallel therewith. An armature including a permanent magnet is laterally movably disposed between a pair of upstanding legs formed at a free end of the yoke. Movable contacts are operationally coupled to the armature. The upstanding legs of the yoke have effective areas of magnetic pole. Upon energization of the coil, the armature is moved toward the upstanding leg to close one of the stationary contacts by overcoming the resilient resistance of the movable contact arm. Upon deenergization, the movable contact is held being contact with stationary contact under the magnetic force between the armature and upstanding leg so as to perform a bistable operation.

Abstract: A circuit protector for protecting a circuit from an overcurrent including a U-shaped main yoke, a main permanent magnet arranged between legs of the U-shaped yoke, a main coil wound around the main yoke, a movable member made of magnetic material and arranged at an open end of the U-shaped yoke, a magnetic device for generating a magnetic force for moving the movable member in a direction away from the yoke, a movable contact secured to the movable member and a fixed contact provided in opposition to the movable. The coil and the movable and fixed contacts are connected in series with a circuit to be protected across a D.C. power supply source. When an overcurrent flows through the coil, the coil generates a magnetic flux having an opposite direction to that of a magnetic flux induced by the permanent magnet, so that a magnetic force for attracting the movable member to the yoke is decreased.

Abstract: A switch device comprises a support member having at least first and second stationary contacts thereon. An armature is mounted on the support member by means of a body of elastomeric material that is attached to both the support member and the armature. Deformation of the body of elastomeric material allows the armature to pivot relative to the support member between a first position in which electrically-conductive material of the armature establishes electrically conductive connection between the stationary contacts and a second position in which the armature is spaced from at least one of the contacts. At least one permanent magnet is carried by the armature. An electrically-driven switch actuator is mounted stationarily relative to the support member and has first and second energization states.

Abstract: A magnetic valve that is switchable in two directions is proposed. The valve comprises an armature, which is firmly joined to a valve body; at least two magnetic coils disposed in one plane and having ferromagnetic cores inserted in them; and two pole bodies, which are joined to the cores and with them belong to the electromagnetic circuit, and acts on the oppositely located flat sides of the armature. Permanent magnets are inserted into the pole bodies in such a way that the operative surface area of the pole bodies is divided into a number of zones, each having a homogeneous magnetic orientation in which the number of zones is equal to the number of magnetic coils.

Abstract: A rotary latching solenoid of the type in which a permanent magnet causes a flux flow path to be formed between opposing pole faces of an armature and a base in order to hold the armature in an energized or latched position is improved by providing the pole faces of the armature and base with raised sector portions, each sector portion having a sector face. In the energized or latched position, the sector faces of the armature and base are adjacent to each other and lines of flux flow between them are in a circumferential direction. The holding power of such an armature and base construction is greater than that of previous solenoids in which the opposing pole faces lie in a plane perpendicular to the solenoid axis.

Abstract: The invention relates to a polarized electromagnetic relay with magnetic latching and sliding armature.The magnetic circuit comprises a tubular frame enclosed by two flanges (22, 24), a permanent magnet (14) with axial magnetization fitted between one (22) of the flanges and a flux-diverter (26), and a cylindrical trip coil (30) mounted on a bushing inside the frame (20). The other flange (24) is fitted with a tubular sleeve (46) made of ferromagnetic material coaxially surrounding a part of the moving armature (16) with a uniform radial air gap (jl) interposed. The axial overlapping distance (L) of the armature (16) by the sleeve (46) in the latched position of the relay (10) is greater than the thickness (11) of the flange (24) and/or than that of the frame (20).

Abstract: An electro-mechanical actuator has a ferrous alloy armature movably mounted within a body chamber. Two axially-spaced permanent magnets are arranged radially inwardly of the chamber and partially define the chamber at the ends thereof. A coil surrounds the chamber. The body is formed of a magnetically-permeable material. Because of the high reluctance of the magnets, each magnet forms a short magnetic loop which passes through the adjacent air gap, and forms a long magnetic loop which encircles the coil and passes through the distant air gap. The armature has a bistable toggle-like movement, and may be latched proximate either end wall. If springs are added between the armature and the body, the improved actuator may be used as a proportional position of force transducer within an operating range of armature movement.

Abstract: A polarized electromagnet with bi or monostable operation is provided in which two flux channelling pieces of rectangular shape are disposed one in the other and are magnetically associated by means of permanent magnets, whose axes, parallel to that of the coil, pass substantially through the carcase of said coil, inside which slides a core provided with two plates when the operation is to be bistable.

Abstract: A three-state polarized electromagnet comprises a stationary system (1) surrounded by a coil (5) and a moving system (7). Each system consists of a permanent magnet (2; 14) fitted with pole pieces (3, 4; 12, 13). The ends of the pole pieces are bent-back towards each other in order to define four air-gaps (E1 to E4) for permitting displacement of the moving system (7) between two end positions. One end portion of a pole piece forms part of only one air-gap and the air-gap faces are joined to pole faces of permanent magnets having the same polarity in order to reduce to zero the fluxes within the air-gaps which are closed when no excitation is applied and in order to permit a return to a stable central position.

Abstract: A proportional pressure control device having a motor with a housing and a reciprocably movable armature oriented in the housing for movement between first and second limit positions. A valve body is secured to the motor housing. A platelike poppet valve member is secured to the armature on at least one end thereof. The valve body has a fluid pressure port thereon and it extends into the interior of the valve body to a chamber. A flow restrictor device is provided in the pressure port to restrict fluid flow from an external pressure source into the pressure port and the chamber. A nozzle outlet structure is provided in the chamber and has an annular flat valve seat thereon directly opposing the poppet valve member. The spacing between the valve seat and the poppet valve member effects a controlling of the magnitude of the fluid pressure developed in the chamber.

Abstract: The electromagnet comprises the yokes (31, 32a) which are moveable in relation to an armature (21a) and a winding (25) surrounding a part of the magnetic circuit, this armature (21a) comprised of a magnet (22a) fitted with two pole pieces (23a, 24a) projecting past both extremities of this magnet, at least one of the said pole pieces having its extremities bent at right angles in order to define the air gap inducing counter forces following a direction perpendicular to the axis of the permanent magnet (22a).A second armature (21b) identical to the first (21a) is located parallel to and facing the first. Two yokes (31; 32a, 32b) join the air gap zones of the two armatures located facing each other in such a way that the magnetic circuit constitutes a sequence of armature and yoke forming a rectangle. Two windings (25, 28) are located on opposite sides of the above-mentioned rectangle.Application primarily in the construction of electromagnets of low inertia, small volume and low leakage flux.

Abstract: Calibrated fluid flow control device comprising several valves (1a to 1b) mounted in parallel on a single body (2) receiving in several housings (6), several seats and several interchangeable calibrated nozzles, the housings (6) being connected to a common input (8) and a common output (7). The valves are preferably bistable electrovalves.

Abstract: A solenoid-operated pressure-fluid valve for reversible control of both supply and exhaust functions of a double-acting fluid-pressure device. A valve body has an inlet port communicating with an inlet chamber and an exhaust-outlet port communicating with an outlet chamber. The valve body has first and second control-port connections for connection to the respective control ports of the double-acting device, and each of these connections communicates with a valve seat in each of the chambers. A rocker arm is pivoted between the two chambers and carries two valve members in each of the two chambers.

Abstract: A solenoid valve for liquid and gaseous media whose valve closure piece or pieces (24) can be actuated by an armature (20') which is movable relative to the valve seat or seats (18, 19) is disclosed. The armature lies in the magnetic field of at least one electromagnet (4, 5) and of at least one permanent magnet (10) arranged outside the field of the electromagnet. The valve is closed via the armature (20') and has operating air gaps which change in opposite directions upon a movement of the armature. The electromagnet is provided with a core (4) whose ends form three magnet poles (10, 11, 12). The armature (20') which contains the permanent magnet (21) has two pole pieces (20') which extend between the three magnet poles (10, 11, 12) of the electromagnet to form four operating air gaps, the pole pieces being combined with the permanent magnet and connected with them to form as assembly.

Abstract: The bistable electromagnet comprises a magnetic circuit partially surrounded by a winding constituted by a series of links (M1, M2, M3, M4, M5, M6) interconnected by air gaps, the links of a first type being movable relative to the other links of a second type, certain types of links comprising a permanent magnet (1, 3, 5, . . . ) provided on its pole surfaces with pole pieces (7, 8; 11, 12; 15, 16; . . . ) whose ends define two air gap zones with the neighboring links of the other type.

Abstract: A solenoid including a plunger supported on a shaft so as to be axially and rotatably moveable, a rotator rotatably supported on the shaft, a coil for generating magnetic flux to attract the plunger to the rotator by a magnetic force, and yokes for completing magnetic circuits such that the plunger and rotator are subjected to no radial force by the magnetic force and no axial force after they are drawn to each other.

Abstract: An electromagnet is proposed which serves in particular to actuate a fuel injection valve for fuel injection systems in internal combustion engines. The electromagnet includes a first pole piece disposed at one side of a first permanent magnet and a second pole piece disposed at the other side of the first permanent magnet. The pole pieces each have one conduction section bent at an angle, which sections are oriented toward one another and define a gap therebetween. Divided from the first permanent magnet by the conduction sections, a magnet coil is disposed on each pole piece. The first pole piece has a pole oriented toward the armature, and the second pole piece has a pole. When the magnet coils are not excited, the armature is drawn in the direction toward the poles by one component (.phi..sub.p2) of the permanent magnetic flux. If the magnet coils experience a flow through them of a current (i) in such a manner that an electromagnetic flux (.phi..sub.

Abstract: A bistable actuator comprising a permanent magnet assembly secured to an armature shaft and a pair of core elements axially disposed on either side of the permanent magnet assembly. The cores have axially opposed inner and outer annular extensions defined in each core by a central axial opening which supports the armature shaft and an annular recess in which is received an electrical coil. The permanent magnet assembly comprises inner and outer annular axially magnetized permanent magnets radially spaced by a ferromagnetic ring so as to be aligned with the inner and outer core extensions.

Abstract: A magnetic valve in which two cylindrical soft-iron cores are provided which are disposed parallel to one another. The soft-iron cores are each surrounded by a coil. An armature of magnetically conductive material which carries a valve body is caused to move inside the soft-iron cores. Between the two coils, an axially magnetized permanent magnet is disposed in circular-annular fashion. The soft-iron cores have a magnetic short-circuit connecting them with one another.

Abstract: A solenoid device adapted for use with an automobile door locking device, for example, comprises a shaft, two magnetic cores, a permanent magnet sandwiched between the cores, two field coils for producing a magnetic flux along the shaft, a magnetic yoke body for forming a magnetic flux path along the outsides of the coils, a magnetic center plate disposed between the coils, and two magnetic yoke end plates. The permanent magnet and the cores are fixed to the shaft to form a magnetic plunger. The center plate includes an annular magnetic flux path portion through which the magnetic plunger extends.

Abstract: An actuator for use in a pickup device for a video disk plunger having a cylindrical yoke made of a soft magnetic material, a pair of tubular solenoid coils disposed in said yoke such that the same polarity appears at adjacent portions thereof, and a movable element disposed axially movably inside of the tubular solenoid coils, the movable element having an axially magnetized permanent magnet and pole shoes attached to both ends of the permanent magnet. Dampers made of a resilient material such as a butyl rubber are secured to both ends of the yoke. The dampers support projections projected from both ends of the movable element such that the projections project axially outwardly of the dampers. A permanent magnet for magnetically attracting a stylus is secured to the outer end of one of the projections.

Abstract: A polarized electromagnetic relay has two L-shaped yokes with a permanent magnet disposed therebetween. Each yoke has a long leg and a short leg with a coil wound around the long legs of the yokes. The long leg of a similarly L-shaped armature is also disposed between the long legs of the yokes and the armature is pivotally mounted at its short leg so that the free end of the long leg of the armature executes switching movements between the short yoke legs and forms a rectangle in combination with the yoke arrangement. The armature may be mounted centrally or single-sided with respect to the yoke legs for monostable or bistable switching behavior of the relay. The compact arrangement of the yokes and armature permits a number of contact elements to be disposed beneath the coil at both sides of the long armature leg, with the armature causing movement of spaced spring contact elements for making and breaking with corresponding fixed contact elements.

Abstract: Trip solenoids are disclosed in which a permanent magnet is positioned exteriorly of the armature case. In one version, a rotary solenoid has a permanent magnet between a ball race plate and the case and has a magnetic force sufficient to hold the rotary solenoid in its actuated position when the power is removed from the solenoid coil. An axial version of the trip solenoid is also disclosed.

Abstract: An electromagnetic device having a ferromagnetic core having first and second legs and a third leg wherein opposed pole faces define a gap. A source of latching flux retains an armature in contact with one of either of the pole faces. A primary coil and a secondary coil are coupled in tandem to the first leg of the ferromagnetic core. The second leg is saturable under the cumulative flux created in the first leg when the secondary coil allows only a unidirectional flux flow in the first leg. The saturation of the second leg transfers a portion of the operating flux from the second leg to the gap operably moving the armature mounted therein.

Abstract: An electromagnetic device which comprises an excitation coil wound to assume a substantially cylindrical shape having an axially extending hollow space; a plunger made of a magnetic material accomodated within the hollow space for movement in an axial direction of the excitation coil between retracted and projected positions; yoke means made of a magnetic material and engageable with one end of the plunger to provide a magnetic path which may be interrupted in response to the movement of the plunger towards the projected position, said yoke means extending between the respective ends of the excitation coil and positioned external of the said excitation coil to provide a closed magnetic circuit including the plunger and the magnetic path; a permanent magnet made of intermetallic compounds of cobalt and one more rare earth elements disposed in the closed magnetic circuit so as to develop a magnetic force of attraction attracting the plunger onto the end of the yoke means opposed to the end of the plunger and ho

Abstract: A linear servo system including a linear motor with a moving permanent magnet the flux of which interacts with current flow through a stator winding. A position servo loop controls the position of the permanent magnet and preferably includes a position transducer located within the motor air gap. The servo system when used in combination with a disk drive preferably includes a coarse/fine positioning program to first move to the desired disk track area and to then move to the center of the disk track. The motor winding located in the air gap can be made of iron or copper clad iron to reduce the size of the effective air gap.

Abstract: An electric trip solenoid employs a pair of low-cost retaining or holding magnets in an open frame arrangement in which the magnets are positioned on opposite sides of the flat surfaces of a pole and in contact with the pole and the legs of an open frame. The magnets are thickness oriented so as to distribute their flux through relatively large areas avoiding regions of high flux density. In one embodiment the release point may be adjusted by rotating a screw in a closure plate to vary the reluctance of the secondary flux path therethrough.

Abstract: A polarized electromagnetic device is disclosed having a generally I-shaped magnetic core member, a coil which is wound on the center portion of the core member, a pair of permanent magnets which are arranged in parallel with and outside of the respective end portions of the core member, and mutually confronting first and second armature plate members which are joined together through the pair of permanent magnets, with each magnet at the opposite end portions of the armature plate members in order to provide a spacing for accommodating the core member between the armature plate members, and consequently leaving a gap for relative movement therein. The core member and armature plate members are supported to be swingable relative to each other for movement about a center transverse axis of the center portion of the core member.

Abstract: An electromagnetic device with a ferromagnetic coil having first and second legs completing a closed magnetic circuit. An armature is pivotably mounted on a flux return bracket for optionally contacting the ferromagnetic core at two locations. Latching magnets cooperating with the flux return bracket retain the armature against the ferromagnetic coil at either of those two locations. A gap is provided between the armature in the ferromagnetic core at the location opposite from the location where the armature contacts the ferromagnetic core. A source of operating flux cooperates with the ferromagnetic core for selectively establishing a magnetic flux across such gap which may then operatively pivot the armature to contact the ferromagnetic core at the second location thereby creating a gap between the armature and the ferromagnetic core at the first location.

Abstract: A self-sustaining solenoid which is adapted so that when applying an operating current to a coil, a moving iron core disposed in the coil is attracted into contact with a fixed receiver. A magnetic yoke is provided to extend between the fixed receiver and the end portion of the moving iron core projecting out of the coil, and a permanent magnet is disposed on the magnetic yoke at least at one end in the direction of movement of the moving iron core. When the moving iron core is held in contact with the fixed receiver, magnetic fluxes emanating from the permanent magnet mostly pass through the moving iron core, the fixed receiver and the magnetic yoke, and even if the operating current is cut off, the moving iron core is retained in contact with the fixed receiver.

Abstract: An electromagnetic device having an armature mounted in the gap of a ferromagnetic core for selective contact of either of opposed pole faces. A source of latching flux retains the armature in contact with either of the pole faces while a flux return bracket conducts flux between the armature and the source of latching flux. The source of latching flux has a surface area perpendicular to the flux path greater than the length along the flux path creating a low reluctance path for a portion of the operating flux.

Abstract: The permanent magnet is mounted within the coil in engagement with the magnetic frame so when the coil is energized by a pulse of DC voltage of polarity giving a coil flux aiding the magnet the plunger is actuated against the bias of the spring to move the plunger close enough to the magnet to be retained. A pluse of opposite polarity gives a coil flux opposing the magnet flux so the holding force is less than the spring force and the plunger is moved to its inactive position.

Abstract: In a bistable electromagnetic relay composed of a U-shaped yoke provided with excitation coils, the arms of the yoke are inserted between the pole-pieces of a pivotally mounted H-shaped armature comprising a permanent magnet. A flexible strip attached to the armature carries two movable contacts which are applied against two stationary contacts in order to provide an electrical connection between the contacts. Only a very small proportion of the flexible strip performs a conducting function, there is no permanent connection between the strip and a fixed terminal, and a very short path is provided for current flow. The double-break action of the relay has the effect of reducing stray capacitance between open contacts.

Abstract: A linear electric motor comprising a frame of magnetizable material, an armature provided with a permanent magnet having a pair of magnetic poles movably supported in the frame, and a stationary winding circumposing the armature, the winding comprising a pair of coils wound on a pair of axially spaced bobbins secured to the frame. The bobbins supporting the coils are disposed adjacent to the end portions of the frame. Each coil circumposes a pole piece secured to an end portion of the armature and each of the coils is disposed between one of the magnetic poles and the frame. Energization of the coils of the stationary winding exerts a force on the coils with respect to the armature resulting in linear motion of the armature.

Abstract: A magnet movable under the influence of magnetic edge forces is arranged between stationary magnets.The magnet is surrounded by a release coil in such a manner that the coil part contributing to the force active in the release direction is located in the space formed by the stationary magnets.

Abstract: In the disclosed shutter, shutter blades are reciprocatable between exposure start positions and end positions. Reciprocative rotating electromagnetic drive sources with stators and rotors reciprocate the shutter blades. Magnetic members on the stator facing the rotors hold the latter at positions corresponding to the blades' start positions and are movable to vary the gaps formed between the rotors and themselves.

Abstract: Photographic camera light controlling apparatus for driving a light admitting system, comprisingfour stator electromagnetic poles defining therebetween an intervening field space containing a linear path, including first and second transversely opposed poles at one path end and third and fourth transversely opposed poles at the other path end, with said first and third poles on one path side and second and fourth poles on the opposite path side,a field coil mechanism energizable alternately in opposite current flow directions and coordinated to energize said first and fourth poles with one polarity and said second and third poles with the opposite polarity, and alternately vice versa, thereby providing in such field space oppositely polarized electromagnetic fields,a permanent magnet for driving such system, having its permanent poles arranged transversely of the path and forming a surface magnetized permanent magnet with one permanent pole facing said first and third poles and the opposite permanent pole fac

Abstract: Magnetic actuation methods and apparatus provide in an air gap a first magnetic field and a magnet having a second magnetic field at an angle to and interacting with the first magnetic field. A pivot axis for the magnet is located laterally and entirely outside of the air gap, and such magnet is displaced in the air gap with the interacting first and second magnetic fields about the laterally located pivot axis. In practice, the air gap may be provided by a pair of pole pieces and the magnet may be located on a lever extending past the air gap. Such lever may be pivoted about an axis extending through one of the pole pieces. The lever is then displaced with the magnet and the magnetic field in the air gap.

Abstract: Magnetically actuated impact equipment useful for high speed printers, punches or the like, is disclosed. Actuating magnets formed of materials characterized by wide hysteresis loops such as samarium-cobalt and mischmetal cobalt are disclosed. As disclosed, these magnets are oriented with like poles facing one another along opposite sides of gaps which run lengthwise of a print line. Magnetically actuated devices are shown with coils extending into the gaps with the plane of each coil being parallel to the print line. In one embodiment of the invention the magnets are arranged in upper and lower banks with coils on different movable devices extending upwardly and downwardly into gaps between the magnets in each bank. Another embodiment discloses coil-carrying devices which are mounted so as to be stepped along the gaps to various printing positions.

Abstract: A polarized magnet system for a relay has a rotary armature having a pair of opposed parallel pole-piece plates which enclose permanent magnets and which terminate in spaced pole-plate piece ends which surround the pole-pieces of a coil core in clamp-like fashion and form working air gaps with the core. The ends of the ferromagnetic pole-piece plates are angled to form a tab in the direction of the coil core so that the working air gaps are shifted in the direction of the coil permitting the permanent magnets to occupy the entire distance between the pole pieces commensurate with the overall armature length.

Abstract: An electromagnetic device having a gap area for conducting operating flux has a source of counter flux proximate the gap for confining operating flux to the gap area.

Abstract: A release electromagnet comprises a permanent magnet assembly including a pair of yokes disposed in parallel relationship with each other, and a permanent magnet held between the yokes for attracting an armature, a winding disposed on one of the yokes which when energized produces a magnetic flux to reduce the attraction effect upon the armature, and a member of non-magnetic material disposed between and connecting the yokes together to reduce the energy required to release the armature.

Abstract: A moving system constituted by a permanent magnet and pole-pieces is accurately guided in axial translational motion within the coil unit of an electromagnet and enclosed within a coil form member, the axis of magnetization being perpendicular to the axis of the coil unit. Air-gap zones are located at both ends of the coil unit and a stationary yoke surrounds the two ends of the coil. Flat portions of the yoke which are parallel to the axis of magnetization each penetrate respectively into one air-gap zone so as to ensure that, at least in one stable position of the moving system, a flat portion of the yoke is in contact with one of the pole-pieces while the other flat portion is in contact with the other pole-piece. Better magnetic coupling between the coil, the air-gaps and the permanent magnet as well as higher operating efficiency are achieved.

Abstract: A linear solenoid device includes a stator defining a cylindrical stator opening, and a pair of axially spaced cylindrical stator pole surfaces. An armature is mounted within the stator opening for movement parallel to the stator pole surfaces. The armature defines a pair of armature pole surfaces which overlap the stator pole surfaces by varying areas as the armature is moved. Annular air gaps are defined between the stator pole surfaces and the armature and the armature has mounted thereon a pair of cylindrical radially polarized permanent magnets, each such magnet being adjacent one of the armature pole surfaces. When a stator coil is energized, movement of the armature results from the varying reluctance across the air gaps as the armature pole surfaces overlap varying areas of the stator pole surfaces and, also, from repulsion of the permanent magnets. As a consequence, higher force outputs are attainable.

Abstract: By applying an operating current to an operating coil, a moving iron core disposed in the operating coil is attracted deeply thereinto to butt against a fixed receiver. By applying a return current to a return coil, the moving iron core is pulled away from the fixed receiver. At least one of the moving iron core and the fixed receiver is divided into two parts in the direction of travel of the permanent magnet and a permanent magnet is sandwiched between the two parts to couple them together. The permanent magnet is magnetized by an operating magnetic field set up by the operating current and demagnetized by the return current.

Abstract: A moving element is held without contacts in a relatively stable holding position, out of which it is released by the application of an external force. The relatively stable holding position is obtained by superimposing a potential field of magnet edges by a further potential field based on a mechanical bias of the moving element or a magnet in such a manner that the curve of the total potential has a trough corresponding to the holding position. By applying an external force, the moving element is moved to a peak position of the total potential curve, whence it is subject to accelerating forces. Preferably rare earth magnets are used to form the potential field of magnet edges. In a print hammer actuator the moving element includes a moving coil.

Abstract: A polarized relay in which the poles of an electromagnet project toward an armature on either side of a pivot support which allows the armature to pivot toward one pole or the other. A pair of permanent magnets each share one pole respectively with the poles of the electromagnet. The other pole of each permanent magnet has a surface extending on either side of the shared pole so as to have a portion closer to the pivot and a portion further away from the pivot relative to the shared pole.

Abstract: An electromagnetic locking type actuator is constituted by a control member reciprocatable in a fluid passage to control the fluid pressure in the passage, an electromagnetic device for applying a first magnetomotive force to the control member, and a magnetic device for always applying a second magnetomotive force to the control member. In the actuator, when an electric current in one direction is applied to the electromagnetic device the first and second magnetomotive forces are added to move the control member in an attracting direction so that the control member is attracted and held at its movement terminating position by the magnetic device even after the first magnetomotive force no longer acts at that position. When an electric current in a direction opposite to the one direction is applied to the electromagnetic device the first and second magnetomotive forces cancel each other thereby maintaining said control member in a magnetically released state.