Abstract: A magnetic actuator for reciprocating motion of a compressor diaphragm, piston or the like. The actuator comprises a stator with stator poles, excitation windings, and a backing plate. Non-magnetic support arms carry arced magnet poles and actuate a pair of compressed diaphragms. With the introduction of coil current, magnet poles are attracted to the central stator poles and repulsed by outer poles. A torque about pivot results and hence movement of arms with consequential actuation of the diaphragms. Performance is improved by increasing the flux produced by the electromagnet, thereby reducing flux leakage and fringing.

Abstract: An electromagnetic actuator for driving a movable plate equipped with an optical element such as a mirror on the basis of the operation principle of a galvanometer. The structure of the movable plate is simplified, and a driving coil and a wiring are formed by aluminium vapor deposition to improve durability. When an impact brings the movable plate outside the allowable rocking range of the movable plate, a stopper prevents excessive displacement of the movable plate to thereby prevent destruction of a torsion bar that supports the movable plate. Moreover, electrical connection in the torsion bar is eliminated to prolong the service life, and a production process is simplified to reduce a production cost.

Abstract: An electro-optic device which includes a mirror array attached to a base substrate is disclosed. The mirror array comprises a substrate having a plurality of spaced-apart mirrors with underlying cavities (each having a diameter at least about the same size as that of the overlying mirror) formed therein. The base substrate includes a plurality of electrodes as well as a plurality of electrical interconnections. The mirror array is attached to the base substrate so that each mirror of the array as well as a cavity are supported above a set of electrodes. Each mirror of the mirror array rotates relative to the major plane of the substrate in response to an electrical signal. The application of an electrical potential to each mirror relative to at least one electrode of the set of electrodes causes the desired rotation (depending on the magnitude of the electrical potential) up to an angle of about 20 degrees.

Abstract: A linear actuator includes a plurality of magnetic plates and a ferrite core with a conductive cover which are mounted on the actuator body to generate a permanent magnetic field. The linear actuator also includes a metal bobbin which has an outer surface and which is formed with an aperture that defines an inner surface for the bobbin. Further, the bobbin is formed with a gap which extends along its length and which intersects the bobbin from its inner to its outer surface. An insulating insert is placed in the gap. Finally, a winding is wrapped around the outer surface of the bobbin to form an electromagnetic coil, and the coil on the bobbin is slidingly mounted on the actuator to receive the ferrite core through the bobbin's aperture. Electrical current can then be selectively applied to the winding to interact with the permanent magnetic field and thereby cause reciprocating motion of the coil.

Abstract: An actuator made up of a plurality of actuator elements is provided which actuator provides long travel in one dimension and short travel in five additional dimensions, with each actuator element providing long travel in the one dimension and short travel in at least two additional dimensions. For preferred embodiments, each actuator element includes a suspension core, the long travel being in one linear dimension and each actuator element providing short travel in two additional linear dimensions and at least one rotary dimension.

Abstract: A thin electromagnetic transducer includes a permanent magnetic plate, a vibratory diaphragm disposed in opposing relation to the permanent magnetic plate, a resilient buffer member interposed between the vibratory diaphragm and the permanent magnetic plate, and a support member for regulating the position of the vibratory diaphragm relative to the permanent magnetic plate. The permanent magnetic plate is of rigid structure, having a parallel striped multipolar magnetized pattern and a plurality of air-discharge through-holes are arranged in neutral zones of the magnetized pattern. The vibratory diaphragm is formed of a thin and soft resin film on which a coil is formed by printing. A linear portion of the conductor pattern is disposed in a position corresponding to the neutral zones of the permanent magnetic plate, and the vibratory diaphragm is supported such that the vibratory diaphragm can displace in a thickness-wise direction.

Abstract: An annunciator for an implantable medical device encapsulated within a casing comprises a magnetically permeable stationary ring member including an integral inwardly projecting peripheral flange having opposed sides on which electrically conductive coils are mounted. An oscillating member encompassed by the stationary ring member includes a planar magnet member having opposed surfaces of opposite polarity and planar pole pieces are mounted to the first and second surfaces, respectively, in a sandwich-like construction. The oscillating member is movable along a longitudinal axis between extreme positions whereat the first pole piece, then the second pole piece is proximate the ring flange. Cyclic energization of the electrically conductive coils generates a cyclically alternating magnetic field, which interacts with the magnetic field of the oscillating member causing its oscillation between the first and second extreme positions.

Abstract: The present invention relates to a planar type electromagnetic actuator of two axis construction, having two movable plates (12A, 12B) with pivotal supports at right angles to each other. A pair of static magnetic field generating devices (4, 5) are arranged facing each other on either side of the movable plates (12A, 12B), and aligned with one diagonal direction of the movable plates (12A, 12B) so that a magnetic field acts on the movable plates (12A, 12B). A magnetic force due to the mutual action with a current flowing through drive coils (15A, 15B), acts on the movable plates (12A, 12B), to thus drive the movable plates (12A, 12B). As a result, the number of components for the magnetic field generating devices can be reduced, the construction of the electromagnetic actuator simplified, and construction costs reduced.

Abstract: An electromagnetic active vibration actuator configuration combines two modes of operation to obtain the advantages of long stroke and linearity of voice coil type actuators and high efficiency of dual-gap solenoid type actuators. A coaxial stator shell surrounds an axially vibratable armature. Either the stator or the armature can carry one or more coils and/or permanent magnets, however usually the magnets are located on the armature for their contribution to vibrating mass. Alternate coils and alternate magnets are made opposite in polarity, the stator armature pole pieces being held symmetrically staggered relative to the stator pole pieces by end springs or flexures that allow axial vibration when AC is applied to the coils.

Abstract: An electromechanical device has a coil configuration comprising an insulating substrate (30) carrying a first group of 12 series-connected spiral conductor patterns (21a-21m) and a second group of 12 series-connected spiral conductor patterns (22a-22m). Some of the conductor patterns (21a, 22a, 21d, 22d, 21e, 22e, 21i, 22i, 21j, 22j, 21m and 22m) are disposed on the upper side of the substrate (30). Other ones of the conductor patterns (21b, 22b, 21c, 22c, 21f, 22f, 21h, 22h, 21k, 22k, 21l and 22l) are disposed on the underside of the substrate (30). The conductor patterns on both sides of the substrate (30) are electrically interconnected by means of plated-through connections (40). The first group is in arranged in parallel with the second group by means of common connection electrodes (51 and 52). The conductor patterns (21a-21m) of the first group and the conductor patterns (22a-22m) of the second group are carried by the same substrate (30).

Abstract: A force rebalance accelerometer includes a proof mass suspended by one or more flexures between stationary mounted upper and lower excitation rings. Pick-off capacitance plates formed on opposing sides of the proof mass form capacitance elements whose capacitance varies in response to displacement of the proof mass to provide a displacement signal. The displacement signal is applied to one or more electromagnets, used to force the proof mass back to a null or at-rest position. The drive current applied to the electromagnets thus represents the force or acceleration applied to the accelerometer. The electromagnets include a magnet and a pole piece which forms a magnetic return path. In order to relieve stresses due to thermal expansion, the magnet is spaced apart from the pole piece to enable the bonding area to be constrained to a minimum which, in turn, reduces the overall stress on the accelerometer.

Abstract: A ferrite resonating device operative for example as an oscillator or filter includes a mechanism for mechanically varying the position of a permanent magnet while maintaining a fixed main gap in which a ferrite resonating element is placed so that wide tuning can be achieved while maintaining electrical parameters substantially constant.

Abstract: A voice coil actuator is disclosed having a housing, a pole piece, a magnet structure and a coil. The housing is cylindrical and defines a vertical axis. The housing further defines a base portion, an outer wall extending axially from the base portion and a top plate extending radially inward from the outer wall. The base portion defines an annular channel coaxial within the base portion. The pole piece is coaxially disposed within the housing. A gap is defined between the top plate and the pole piece. The coil is moveably suspended coaxially within the gap. The magnet structure is fabricated from rectangular shaped radially magnetized permanent magnets. The magnets are arranged in a polygonal shape and disposed in the channel.

Abstract: An annunciator is provided for an organ stimulating system which is implantable in the body of a patient. A tubular support member is mounted at one end on the casing for the organ stimulating system and extends to a free end and an electrically conductive coil encircles the support member. An elongated oscillating member includes a field return member of magnetically permeable material which is spaced from and generally encircles the support member. The field return member extends between an integral head member at a proximal end generally proximate the free end of the support member and a distal end generally proximate the casing. A stack member is mounted on the head member and extends away therefrom toward the casing for the organ stimulating system.

Abstract: The active vibration-absorber is, in particular, an engine mount for motor vehicles. A magnet system has a magnet casing which receives a permanent magnet and which is guided in the assembly so as to be capable of movement in the axial direction. An electrical moving coil projects perpendicularly from a carrier plate and moves into the magnet casing. The carrier plate can be connected to a vibrating machine part, such as between the engine and the vehicle frame. The magnet system is held, in the axial direction, by a magnetic leakage field which is present between the magnet system and stationary ferromagnet.

Abstract: A tamper indication system for use with combination locks can indicate or signal that unauthorized manipulation of one or more of the lock components has occurred. In one mode, the tamper indication system senses unauthorized retraction of the lock bolt. Unauthorized movement of the lock cover or combination dial can also be sensed. Sensing can be achieved by generating a mechanical action responsive to the unauthorized manipulation and converting the mechanical action into an electrical signal for sensing and indicating. The mechanical action can utilize a snap action motion generation system, non-contact means such as magnets or a spring biased switch.

Abstract: A reciprocating magnetic body support structure for a linear motor or a linear alternator is claimed. The body comprises a cylindrical, metallic support sleeve having a plurality of longitudinal slots evenly spaced around the circumference of the sleeve. An equal number of magnet segments is mounted to the sleeve extending over at least a portion of the associated slot and attaching to the wall of the sleeve on both sides of the associated slot. The longitudinal slots preferably extend completely through the sleeve from near one longitudinal end of the sleeve to near an opposite longitudinal end of the sleeve. The sleeve is preferably stainless steel or titanium, but should, regardless of metal, have a high resistivity, i.e., above 50 micro ohms per centimeter.

Abstract: A moving coil linear actuator including an elongated permanent magnet having a cross-sectional width substantially greater than its edge height and having an elongated length of soft magnetic material disposed along one or both edges of the permanent magnet to enhance the magnetic field strength in the gap through which the moving coil translates.

Abstract: A motion producing device in the form of a linear actuator, circular pump, or a robotic or prosthetic limb which functions to produce many kinds of work is provided. The device includes a linear series of alternately spaced fixed and polarity reversible magnets. The fixed and polarity reversible magnets may have more than one magnet assembled as a force unit of magnets of fixed polarity or reversible polarity which is surrounded by a rigid electrically insulating material and that carries rigid electrical conductors in the form of tubes. Between each magnetic force unit is an elastic electrically insulating material allowing expanding or shrinking of the distance between the magnetic force units in accordance with the polarity reversal of the reversible magnetic force units. The elastic expansion or contraction material carries flexible elastic tubes that connect with the rigid tubes to hold a current carrying electrolyte to carry electrical current from a D.C.

Abstract: A cylindrically-symmetrical moving coil linear actuator utilizes axially-magnetized cylindrical magnets to provide flux-focused interleaved magnetic circuits. The moving coil linear actuator includes a cylindrical shell that has a closed end and open end. A magnetic core is disposed within the shell to define an annular air gap between the shell and the core. The core includes a first set of axially-magnetized cylindrical permanent magnets having a first direction of magnetization and disposed in proximity to the closed end of the shell. A second set of axially-magnetized cylindrically permanent magnets has a second direction of magnetization which is opposite of the first direction of magnetization and is disposed in proximity to the open end of the shell. A first ferro-magnetic pole piece is disposed between the first set of magnets and the second set of magnets. A second ferro-magnetic pole piece is disposed between the second set of magnets and the open end of the shell.

Abstract: Magnet assemblies for installation into a voice coil motor is described. A pair of magnetic pieces are molded into circular arc shapes of different radii and positioned concentrically across a gap. The ends of such the pair of magnet pieces, are joined to a similarly-molded other pair of magnet pieces. The direction of magnetization of the former pair of magnet pieces is reverse that of latter pair of a magnet pieces. On the upper curved surface of each of the two units of lower magnet pieces of smaller radius, a cut plane, for example, is formed in order to provide unbalanced cubic volume between one half and the other half from the center plane of a magnet piece, thus increasing the gap magnetic flux density being generated inside the gap at the sections of larger cubic volume, thereby improving overall evenness of the gap magnetic flux density distribution.

Abstract: A device for making electrical connection to a reciprocating element, such as to a voice coil of an actuator. An electrical flow path utilizing the helical centering springs as a primary element in conducting current ensures reliable current flow to a reciprocating element and avoids high-speed flexing of brittle wires. Hard-wired connections are utilized only between stationary elements. A second double-coil actuator embodiment employs a coaxial, substantially co-extensive pair of springs as the input and return current flow paths for each actuator.

Abstract: A lower die having a first recess corresponding to one of outer shapes of the element, and an upper die having a second recess are provided. The outer diameter of the upper dies is smaller than the inner diameter of the first recess so that a gap is formed between the inside wall of the first recess and the outside wall of the upper die. A workpiece is put between the lower and upper dies, and the upper die is pressed against the lower die to form the element.

Abstract: A fine tracking miniature galvanometer actuator is used as a fine tracking positioner for a read/write head in the optical disk drive of an information storage and/or retrieval system. An efficient magnetic circuit is used in conjunction with a small and lightweight rotor design which offers high performance characteristics in terms of frequency response and sensitivity. No mechanical springs or torsion bars are necessary to maintain the rotor in a neutral or zero position. The present invention is also useful in other systems using electro-optical transducers including reflecting-type galvanometer recording systems used for producing variable-area sound tracks .

Abstract: A force generating apparatus having spacings through which magnetic fluxes are traveled, a magnetic circuit including two permanent magnets supplying magnetic fluxes to the spacings and a conductor disposed in the direction perpendicular to the magnetic fluxes in the spacings is comprised of two pair of permanent magnets of the same size, and a member for disposing the two pair of permanent magnets such that magnetic axes thereof are opposed in parallel to each other, wherein a total sum of magnetic moments caused by the two pair of permanent magnets is cancelled out. Therefore, the force generating apparatus can be prevented from producing a harmful torque even if an external magnetic field acts thereon.

Abstract: A returnless coil motor assembly comprising a voice coil, first and second magnets, the poles of the first and second magnets providing aligned, opposing lines of force in first and second opposite directions, a first spacer having a first face adjacent a pole of the first magnet and a second opposite face, a second spacer having a first face adjacent the like pole of the second magnet and a second opposite face, a third magnet oriented between the second faces of the first and second spacers, and the voice coil mounted in close proximity to the third magnet, the third magnet providing lines of force extending in a third direction generally transverse to both the first and second directions, and the voice coil having a direction of motion extending generally perpendicular to the third direction.

Abstract: A swing-type actuator comprising (a) a housing comprising two yokes and permanent magnets attached to the yokes with their different magnetic poles opposing each other, a magnetic gap existing between the opposing permanent magnets; and (b) a swingable arm having one end to which a movable coil is fixed and the other end to which a function member is fixed, such that the movable coil is swingable in the magnetic gap, the movable coil being integrally fixed to the arm by a hold member made of a thermoplastic resin having a modulus of 10.sup.5 kg/cm.sup.2 or more.

Abstract: EGR is controlled by a valve whose actuator is a moving electromagnetic coil through which control current representing the desired degree of valve opening is conducted. The coil is disposed in an air gap of a magnetic circuit such that the magnetic flux passes radially through the coil. A coil spring biases the valve closed when there is no current flow through the coil. When control current is conducted through the coil, there is an interaction with the magnetic flux causing the exertion of an electromagnetic force on the coil against the spring force. Relative pressure acting on opposite sides of the valve will assist the coil motion. As a result the coil moves in a direction to increasingly compress the spring until the spring force balances the electromagnetic force. Consequently the valve is opened in an amount proportional to the control current. The motion of the coil is also electromagnetically damped, and a position sensor provides a feedback signal of the valve position.

Abstract: In a linear actuator including a casing, an output shaft passing through the casing and being mounted slidably in a direction along the axis thereof, a solenoid coil disposed within the casing in coaxial relation to the output shaft, a magnet disposed in such a manner that the magnetic flux thereof is linked with windings of the coil, the output shaft mechanically connected to one of the magnet and the coil to form a movable part, and a spring adapted to urge the output shaft in one direction along the axis thereof, and a spacer made of high permeability material and interposed between the casing and either the coil or the magnet, whichever is fixed on the casing to form a stationary part.

Abstract: A superconductive gravimeter comprises a spool (12, 14, 16) and a circumferential magnet (20, 22, 24), both of which are covered with superconductive material (48, 52, 58, 60) except at the magnetic field gaps (54, 56, 62, 64) between them. A force rebalance coil (28, 30) lies in these gaps and supports a superconductive plate (70) above them. Leakage flux flows through the space between the plate and the circumferential magnet. Variations in gravity result in variations in the weight of the plate, resulting in variations in the height of the space, resulting in variations in the flux in the space, which are detected by a pick up coil (74).

Abstract: An electromagnetic drive apparatus for undertaking linear or circular movements as a flat coil disposed within a magnetic circuit, which may be formed by a iron core having one or more permanent magnets. The magnetic circuit includes at least one plate or coating of electrically conductive material which is spaced from the coil and coextensive with the area of movement of the coil within the magnetic circuit. The electrically conductive material promotes rapid change of the coil current due to induced eddy currents and thus contributes to a low response time, or alternatively to a high response speed, of the drive apparatus, particularly with the use of a pulsed drive signal.

Abstract: An electromagnetic drive actuator including a magnetic circuit comprising at least one yoke having plate-shaped, L-shaped, E-shaped cross section or the like, at least one magnet mounted on the yoke and a magnetic flux extending from the magnet to the yoke, at least one coil arranged so as to cross the magnetic flux and produce a drive force in a direction crossing a plane including the magnetic path of the magnetic circuit when current is applied to the coil, and at least one magnetic shield member provided at the side portion of the coil to thereby prevent a counter drive force from being produced in a direction opposite to a desired direction of a drive force produced by the coil.

Abstract: A superconducting electromagnet comprising an outer core having an aperture; an inner core having a periphery characterized for complementary insertion into the outer core aperture leaving a uniform gap therebetween and a frame means for coupling the outer and inner cores into a fixed position relation. A magnetizing means, such as a coil on the inner core develops an initial flux field. The flux field passes through the inner core, the first gap, the outer core, across the second gap to the inner core in response to excitation of the magnetizing means. The outer and inner cores are coated on all surfaces except opposing inner and outer core gap surfaces with superconductive material. The superconductive material is applied to the outer and inner cores at regions selected to pass induced magnetizing current. The induced magnetizing current circulating via closed current paths within the superconductive material to support the flux free of energy loss on termination of excitation of the magnetizing means.

Abstract: A movable coil driving unit comprises a driven member movably supported by conductive flexible supporting members with respect to a fixed member, a coil fixed to the driven member, and a driving member provided with a power source. One ends of the supporting members are connected to the ends of leads extending from the coil fixed to the driven member, and the other ends of the supporting members are connected to leads extending from the external power source.

Abstract: An electromechanical abutment stop intended particularly for folding machines comprises of a coil (4) and a magnet (2) which are resiliently movable relative to each other. Disposed between coil (4) and magnet (2) is a damper plate (9) of softly resilient material as defined. The abutment sensor is characterized by low overall height. In a preferred embodiment, at least one surface of the damper plate (9) is occupied by projections (10), the shape of which can be used to determine the signal:mechanical pulse characteristic within wide limits, particularly so that the rise in the magnitude of signal will become ever smaller as the mechanical pulse becomes greater. By limiting the free length of travel .DELTA.x coil 4 or magnet 2), it is possible to confine the signal within an upper limit or threshold.

Abstract: A rotary-type electromagnetic actuator for a toy includes a cylindrical magnetic stator fixedly mounted within a housing, a rotor arranged concentrically within the stator and rotatably supported by a shaft within the housing, a coil wound on the rotor for causing the rotor to rotate back and forth by being energized and deenergized, a commutator fixedly secured to the shaft of the rotor for supplying current to the coil, a rotor position-correcting member turnably provided inside the housing in opposition to the commutator and in concentric relation with respect to the housing, and a pair of current feeding brushes embracing the commutator from both sides thereof, each of the current brushes having one end secured to the position-correcting member and another end in pressing contact with a respective commutator bar of the commutator. The coil is energized by dc power supplied through the brushes and commutator.

Abstract: According to a preferred embodiment of the present invention, a double-ended moving coil linear actuator is provided comprising a cylindrical core and a hollow shell disposed around the core to define an annular space between the inner wall of the shell and the outer wall of the core. A non-magnetic spacer is mounted in the annular space to divide the annular space into first and second annular cavities, each of the cavities having a closed end adjacent the spacer and an open end. A first set of magnets is mounted within the first annular cavity to define a first magnetic circuit. A second set of magnets is mounted within the second annular cavity to define a second magnetic circuit. The magnets of these two magnetic circuits are sized and arranged to define a third "interleaved" magnetic circuit which is created by the interaction of the first two circuits. Each of the first two magnetic circuits has a dual-winding coil assembly associated with it.

Abstract: An encoder motor comprising: an encoder incorporated in the encoder motor, for carrying out positional detection and having an encoder code wheel fitted to a motor rotary shaft of the encoder motor; a coil formed as a moving coil movable together with the motor rotary shaft; a magnet operative with respect to the moving coil; and a bobbin in the form of cylinder on which the moving coil is disposed. The bobbin is arranged concentrically with respect to the motor rotary shaft and directly fixed to the code wheel of the encoder.

Abstract: In the permanent magnet type actuator, an armature made of a hollow cylindrical permanent magnet is held to be movable in its axial direction. A stator made of an electromagnet comprises a magnet core having two portions one placed outside of the permanent magnet and the other placed inside of the same, thereby applying a unipolar magnetic field to the armature. A plurality of inductor teeth are formed on the surfaces of the core portions opposing to each other, and means are further provided for energizing a coil of the electromagnet by an exciting current and driving the armature in its axial direction.

Abstract: A linear electromechanical actuator having a variable drive force. The actuator includes a moving coil which moves along a stroke path in response to an input current. A magnetic circuit provides a magnetic flux through which the coil is driven. The flux density along the stroke path is non-uniform, with a higher flux density being present only in that region of the stroke path where a higher actuator drive force is required. Thus, less expensive magnetic material can be used. Since the overall flux density in the magnetic circuit is reduced, the dimensions of the soft iron elements of the magnetic circuit can be reduced without magnetic saturation so as to further reduce construction costs.

Abstract: In an electromagnetic actuator of the type having a planar coil armature mounted for movement in a magnetic field by a plurality of planar flexure springs, the flexure springs lie entirely in the plane of the planar armature.

Abstract: An electromagnetic actuator operable with a source of electric current has two overlapping, oppositely movable armatures that are mounted on resiliently flexible cantilever spring members and coupled together by resiliently flexible spring elements, to provide coordinated cooperative movements of the armatures when energized. The armatures have conductive coils thereon that are connectable to the current source through the spring members and spring elements. A permanent magnet and a pair of flux return plates are disposed near the armatures to provide a suitable magnetic path through the coils. Current flowing through the coils in the magnetic path generates oppositely directed forces on the two armatures. Structure is provided for constraining the coupling spring elements to move in only one direction when such forces are generated, thereby facilitating coordination of desired armature movements in directions substantially opposite to each other and perpendicular to the one direction.

Abstract: An explosion-proof type electro-displacement converter device comprising a cylindrical first yoke attached through a permanent magnet which is at the center of the bottom of a bowl-shaped second yoke, an exciter coil winding supported elastically by springs and arranged in the magnetic path formed between the yokes, the opening of the bowl-shaped yoke is sealed by a sealing means, and an output stem linked with the exciter coil winding and projecting, leaving an explosion-proof gap, through an opening which penetrates through the bowl-shaped yoke or the sealing means.

Abstract: A gas solenoid valve comprising a magnetic circuit formed with a fixed iron core, magnets and a magnetic member; a coil-holder movably provided with respect to the outer periphery of the fixed iron core and having a magnetic coil wound around itself; a sleeve accommodated within the magnets and spaced apart from the outer periphery of the fixed iron core for a predetermined distance; an actuating portion formed with the fixed iron core; the fixed iron core, the magnets and a magnetic member all fixedly covered with a molding resin from outside; and a governing portion engaged with the actuating portion.

Abstract: A torque motor including a housing, a shaft member extending through the housing and supported by bearings, a stationary core in the housing and at least one coil fixed to the shaft member and arranged for rotation with respect to the stationary core within a finite range. Magnets are fixed to the housing for imparting rotational force to the coil and support members are provided in the housing for fixedly supporting the stationary core. The coil is provided with oppositely disposed free ends and extends across the stationary core between the free ends such that each of the free ends projects beyond an outer peripheral surface of the stationary core without contacting the stationary core. The support members include at least two plate members on opposite sides of the shaft member, the magnets being within the housing at portions other than where the support members are disposed.

Abstract: In an electromagnetic drive unit including;a nearly E-shaped yoke having first and second concentric circular arc shaped side yokes respectively inside and outside an arc-shaped center yoke,a first arc-shaped permanent magnet fixed to said first side yoke so as to form a first magnetic gap inside said center yoke,a second arc-shaped permanent magnet fixed to said second side yoke so as to form a second magnetic gap outside said center yoke, anda movable coil member disposed in said magnetic gaps, said first and second permanent magnets are so provided with anisotropy in directions which are different each other that the magnetic flux density in said first magnetic gap will be nearly equal to that in said second magnetic gap.

Abstract: Generally speaking, the present invention relates to an electromagnetic valve for subsea applications. It comprises a valve body, a rotatable core (with an aperture) located within the valve body (it may be shaped like a plug or a ball), a means for creating a magnetic field located between the valve body and the core and electrically conductive windings wrapped around the rotatable core. The windings are connected to a source of DC power and when energized they cause the core to rotate in one direction or the other depending on the polarity of the DC current.

Abstract: There is disclosed an improved electromagnetic actuator for use in shutter applications. Included in the actuator is a magnetic arrangement for minimizing the effects of forces on the actuator armature which would adversely affect armature performance.

Abstract: An electromagnetic actuator is disclosed which develops generally equal and opposing force vectors acting on an armature. This is done by constructing and arranging a permanent magnet assembly, the armature and a conductor assembly to achieve the foregoing results.

Abstract: A small, light-weight direct drive servovalve includes a force motor with a stationary magnet structure and a moving coil with the moving coil coupled to a valve spool by means of a lever mechanism which is pivotally mounted on a pivot hub and which amplifies the actuating force exerted on the valve spool. The moving coil is suspended from the pivot hub by dual convoluted spring diaphragms and through the lever mechanism imparts a linear, reciprocating movement to the valve spool. A tandem valve spool and sleeve assembly is employed and provides for two separated hydraulic systems in a common housing. A fuel metering system for a gas turbine engine utilizing such a direct drive servovalve is provided.