Abstract: An encapsulated stator for use in solenoid-actuated liquid metering device has a bobbin assembly and a plunger guide which are substantially surrounded by a plastic overmold to hold the assembly together and provide a protective housing. Upper and lower ends of the plunger guide are not covered by the overmold, but rather are left exposed so that additional manufacturing and assembly steps may be performed upon the stator. The plunger guide is formed integrally with a support plate and two threaded body for receiving bolts to secure the stator in its operating position. A plastic cap with an integrally molded electrical connector housing for mating engagement with an electrical power supply is secured to the bobbin assembly and retains the core and plunger guide in proper positions relative to the bobbin prior to the assembly being encased in the overmold. A method of manufacturing the encapsulated stator is also disclosed.

Abstract: A new class of actuators and mechanisms use opposing repulsive magnetic forces. The repulsive forces are typically generated between a stationary magnet and a moving magnet, where the moving magnet is coupled to the mechanism output member. The mechanisms are generally configured such that the repulsive force from one electromagnet is opposed by a repulsive force from another electromagnet, where the opposing forces are simultaneously applied to the mechanism's output member. This configuration is similar in certain aspects to the way biological flexor and extensor muscles are configured in a musculoskeletal system. The opposing configuration allows for open loop control of position and stiffness. The actuator mechanism may have both rotary and linear motion output, and may have either a single degree of freedom or multiple degrees of freedom. Permanent magnets can be used to create a baseline repulsive force without electric power, and electromagnets can modulate the repulsive force magnitude.

Abstract: A molding machine includes a drive unit for linearly moving a movable body, such as a movable platen of a clamping apparatus. The drive unit includes a linear motor. The linear motor includes a linear movement body having moving-side magnetic-pole portions and supported in an axially movable manner, and a stationary body having stationary-side magnetic-pole portions adapted to linearly move the linear movement body. The linear movement body is connected to the movable body (movable platen). The linear movement body has moving-side inclined surfaces on which part of the moving-side magnetic-pole portions are disposed. The stationary body has stationary-side inclined surfaces which face the moving-side inclined surfaces and on which part of the stationary-side magnetic-pole portions are disposed.

Abstract: A linear motor comprising a first portion having: a primary magnetic circuit comprising N.sub.e slots alternating with N.sub.d teeth, with N.sub.e =N.sub.d, a multiphase electrical winding having 2P poles being placed inside said slots and, at an instant t when fed with AC, producing an undulated magnetic field of length l and of P periods along the length l of the magnetic circuit covering the N.sub.e slots and the N.sub.d teeth; and a second portion, disposed facing the first portion and separated therefrom by a plane air gap, said second portion having a length L=l+x, where x is the length of relative displacement between the two portions relative to each other, said second portion constituting a secondary magnetic circuit; wherein, facing said air gap, said secondary magnetic circuit comprises a series of teeth and slots along its entire length L, wherein said first portion comprises, along said air gap, and fixed to the primary magnetic circuit at the end of its teeth and its slots, a series of 2N.sub.

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 solenoid operated remote resetting device with a protective solenoid activation circuit is disclosed. The device includes a housing for enclosing and protecting a solenoid with a movable plunger, a movable mechanical operator having an operator arm extending through an opening defined in the housing and a circuit board on which a solenoid activation circuit is mounted. The solenoid activation circuit includes circuitry for protecting the solenoid from overheating due to intentional or unintentional prolonged current flow in the solenoid.

Abstract: A method of winding an electromagnetic coil creating a slot on the side of the winding, in order to allow a space for the plunger support to slide through the coil. Such an arrangement will permit the plunger to be permanently mounted, not movable and allow the coil to travel over the plunger and past it in either direction.Thus by installing a series of plungers and their supports aligned in a straight line, said coil(s) can be moved over the plunger or plungers by sequential energezation and thus create a linear motion, or otherwise referred here as "straight motion".

Abstract: The present invention relates to a stator for a linear motor by staggered core lamination which can facilitate insulation and assembly of a stator core, can freely set an interval of an opening of the stator core, and can reduce loss of the motor by decreasing a magnetic flux density of the core.

Abstract: A solenoid is provided having a housing with a housing bore with a central axis. The housing bore opens at an opening in the housing at a first end. The solenoid further has an actuator extending from the opening, and which is sized to movably slide within the housing bore and within the opening along the central axis. A biasing member is provided in the solenoid for cooperating with the actuator and for biasing the actuator in a direction along the central axis. The solenoid also has an indicator positioned within the housing. The indicator cooperates with the actuator for relative movement therewith, and has an indicator path. An indication receiver is positioned within the housing, and located adjacent the indicator and the indicator path, for generating a signal that is representative of the position of the indicator and the position of the actuator. A method of manufacturing the solenoid is also provided, and includes the step of aligning the indication receiver within a recess in the housing.

Abstract: A molding machine includes a drive unit for rotating and linearly moving a movable body. The drive unit includes a linear motor and a rotary motor. The linear motor includes a linear movement body having moving-side magnetic-pole portions and supported in an axially movable manner and a stationary body having stationary-side magnetic-pole portions adapted to linearly move the linear movement body. The linear movement body has moving-side inclined surfaces on which part of the moving-side magnetic-pole portions are disposed. The stationary body has stationary-side inclined surfaces which face the moving-side inclined surfaces and on which part of the stationary-side magnetic-pole portions are disposed. The rotary motor is incorporated into the linear movement body and is adapted to rotate an output shaft connected to the movable body.

Abstract: A motor structure having an output shaft with a male screw part mating with a female screw part provided on a rotor rotated by electromagnetic interaction to move the output shaft in an axial direction. The female screw is formed of PPS resin, and the male screw part is formed of metal with a silicon nitride surface layer.

Abstract: A new class of actuators and mechanisms use opposing repulsive magnetic forces. The repulsive forces are typically generated between a stationary magnet and a moving magnet, where the moving magnet is coupled to the mechanism output member. The mechanisms are generally configured such that the repulsive force from one electromagnet is opposed by a repulsive force from another electromagnet, where the opposing forces are simultaneously applied to the mechanism's output member. This configuration is similar in certain aspects to the way biological flexor and extensor muscles are configured in a musculoskeletal system. The opposing configuration allows for open loop control of position and stiffness. The actuator mechanism may have both rotary and linear motion output, and may have either a single degree of freedom or multiple degrees of freedom. Permanent magnets can be used to create a baseline repulsive force without electric power, and electromagnets can modulate the repulsive force magnitude.

Abstract: A linear motor including a stator having a drive field magnet extending in a uniform direction, a movable piece including an armature coil opposed to the field magnet, and a carrying member carrying a predetermined portion of the stator, wherein the stator is provided with predetermined magnetic poles for driving the movable piece only at a range in which a change in the magnetic field by the influence of the carrying member is prevented or suppressed.

Abstract: An electromagnetic device includes a solenoid stator comprised of a plurality of magnetic plates stacked spirally and regulated to prevent displacement. The stator is constructed by spirally disposing around its central axis a plurality of magnetic plates each having a uniform thickness and being bent in a curved shape. A support body of the device is so assembled to the stator as to abut its bottom face and a through hole. The support body has a disk part having an outer diameter generally corresponding to that of the stator and a cylindrical part extending upwardly from the central part of the disk part. The top end part of the cylindrical part is fixedly joined to the stator by laser welding. A push rod coupled with an armature is disposed slidably in a hole of the support body. The bottom face of a cap housing abuts the peripheral part of the top face of the stator to press the peripheral part from the upperside.

Abstract: A contactor for a motor vehicle starter comprises a contactor coil, a movable contactor core actuated by a control rod, and a fixed contactor core. It also has an electromagnetic auxiliary control relay which includes a movable relay core carrying a movable contact ring which is arranged for cooperation with at least one pair of fixed relay contacts, carried by a fixed annular contact carrier plate. The relay coil, the contact carrier plate, and the movable contact ring are arranged in axial succession, in that order towards the front of the contactor, and are disposed between the movable contact of the contactor and the fixed core, so that the relay and the contactor are closed in the same, forward, direction.

Abstract: A displacement device with a first part (1) and a second part (3) which are mutually displaceable in a displacement direction. The first part (1) comprises a number of contact bodies (7) which are pressed against the second part (3) against a pretensioning force which is present between the first part (1) and the second part (3). The contact bodies (7) are movable stepwise relative to the first part (1) and are also displaceable perpendicularly to the displacement direction. A stepwise movement of the contact bodies (7) causes the first part (1) and the second part (3) to be displaced relative to one another in the displacement direction under the influence of a friction force present between the contact bodies (7) and the second part (3), while the first part (1) and the second part (3) are supported in an accurate position relative to one another perpendicular to the displacement direction through a displacement of the contact bodies (7) perpendicular to the displacement direction.

Abstract: A novel duel directional electromagnetic actuator includes a case, a core, an electrical current conductive coil and a field coil. The case includes a first case end, a second case end, and an interior wall extending between the first and second case ends. A chamber is defined by the interior wall. An electrical current conductive coil is disposed in the chamber coextensively adjacent the interior wall. The conductive coil has a first coil end disposed proximate the first case end, a second coil end disposed proximate the second case end, and a midpoint. The core has a first core end, a second core end, and an exterior wall extending between the first and second core ends. The exterior wall has a first region adjacent the first core end and a second region spaced from the first region and adjacent the second core end.

Abstract: A linear actuator powered by a Lorentz force. The force is generated by passing an electrical current through an armature spanning a space across a magnetic field established between two permanent magnets. The armature is mounted upon a slider extending between a pair of electrically conductive rails. Reversible linear motion is achieved by switching the polarity of an electrical potential applied across the two rails.

Abstract: An improved cylindrical linear motor is capable of being more easily assembled by changing the constructions of a primary iron core and a primary coil and significantly preventing an over-heating of the primary coil. The motor includes primary toothed sections formed of stacked steel plates, with the primary toothed sections being spaced-apart from one another, a supporting member formed to support the primary toothed sections, coils wound onto the supporting member and between the primary toothed sections, a yoke formed of stacked steel plates and engaged to the primary toothed sections between which the coils are wound, and a secondary iron core inserted within the primary iron cores.

Abstract: A modular planar motor having (a) a mounting plate which has (i) a plurality of openings therein each having an interior surface, (ii) a housing, (iii) a surrounding ridge, and (iv) an undersurface, (b) a superstructure over the mounting plate, and (c) a plurality of modular components each disposed within the openings and having a covering hood for the components, and (d) an aligning and gluing gap between the modular components and the mounting plate and being filled with an adhesive composition for bonding the modular components to the mounting plate.

Abstract: A synchronous type of linear motor using a permanent magnet comprising a primary magnetic pole member (a three-phase coil) and a secondary magnetic pole member (a permanent magnet) each for generating a repulsive force making use of mutual repulsion between a movable element and a fixed board.

Abstract: An electromagnetic actuator has a fixed part (1,2,3,4) constructed of ferrite material and a sliding part (15) constructed of electrically conductive material. The fixed part comprises an outer tubular portion (2), a central disc (1) and two central core members (3 and 4) secured on either side of the disc (1). The sliding part (15) comprises two annular elements (9 and 10) arranged to slide in the gaps (5 and 6) between the cores (3 and 4) and the outer tubular portion (2). Coils (7 and 8) are positioned round the central cores (3 and 4). The two annular elements (9 and 10) are rigidly coupled together by means of a shaft (14) extending through the cores(3 and 4). The actuator acts as a position controller by control of the relative magnitudes of the ac currents supplied to the coils. It can also act as a force applier when the sliding part (15) is moved to a predetermined position and only one coil is energized.

Abstract: An electromagnetic actuator includes a housing made of a magnetic material, a coil disposed in the housing, a stationary core surrounded by the coil and secured to the housing, a movable core adapted to be attracted to the stationary core by excitation of the coil, a return spring for biasing the movable core away from the stationary core, and a joint member coupled to an outer end of the movable core. In this electromagnetic actuator, a cylindrical portion of the joint member made of a synthetic resin is coupled by press-fit to an outer peripheral surface of the movable core at its end, with a resilient locking claw formed on the cylindrical portion being engaged into an annular groove around the outer periphery of the movable core. Thus, the joint member of the movable core can be reliably coupled without use of a coupling member such as a pin or the like.

Abstract: An electrical linear actuator includes a stator assembly and a piston structure. The stator assembly includes a casing having a bore extending therethrough and about a longitudinal axis, a winding structure disposed within the bore and in contact with the casing and a plurality of stator elements connected to the winding structure and arranged circumferentially in a plurality of rows extending parallel to the longitudinal axis within the bore and disposed apart from one another to form longitudinally extending channels between adjacent ones of the rows. Each of the stator elements extends radially inwardly from the winding structure toward the longitudinal axis. The piston structure includes a shaft extending along the longitudinal axis and has an outer cylindrical surface and a plurality of piston elements arranged circumferentially in a plurality of rows extending parallel to the longitudinal axis.

Abstract: The invention is directed to an improved electromagnetic force motor (10) with internal eddy current damping. In the preferred embodiment, the motor is comprised of a body (11), a pair of permanent magnets (15.sub.L, 15.sub.R), an electromagnetic coil (20), and an armature (13). The armature is positioned with respect to the body so as to define two variable-reluctance working air gaps (30, 31) and a constant-reluctance non-working air gap (29). The permanent magnets face one another and are mounted on the body. The body and armature are both adapted to conduct magnetic flux. Each working air gap contains a magnetic flux that is the algebraic sum of a flux attributable to the permanent magnets and a flux attributable to the coil. The non-working air gap contains flux attributable only to the permanent magnets. A current-conducting member (14) is attached to the armature and positioned within the non-working air gap.

Abstract: A single sided servo apparatus comprises a linear motor and a longitudinal carriage which is connected to the linear motor at one end thereof. The linear motor comprises a stator including field magnets arranged linearly and a movable piece including armature coils. The field magnets have a trapezoid-like magnetic flux distribution. An arrangement pattern of the field magnets has a relative tilted angle to an arrangement pattern of the armature coils, so that a free end of the carriage precedes the other end thereof connected to the linear motor. Then, the thrust has a small variation and generates a stable thrust of the servo apparatus.

Abstract: A voice coil motor has a flux return housing with at least one magnet and a soft iron cantilevered core. A coil holder, including an electrical coil spaced from magnet, is telescoped over the core with an air gap between the sides of the coil holder and the sides of core. The coil holder has an open end and a closed end forming with the distal end of the core a pressurized air bellows, which can vertically support a payload such as a Z-axis motion stage. The coil holder is telescopically movable with respect to the core along the air gap supplied with pressurized air through longitudinal air ducts in the core and through transverse orifices extending from the ducts to the air gap. A regulator is connected to a core central bore for adjusting pressure in a bellows chamber between the coil holder closed end and the distal end of the core for supporting the payload.

Abstract: A method of controlling driving power of a double-solenoid electric percussion tool utilizing the change of energizing time of the first solenoid to control the location of a hammer when the first solenoid is switched to the second solenoid so as to increase the driving power of a percussion tool.

Abstract: To improve the movement precision of a synchronous linear motor, it is proposed that the front and rear end faces (11, 12) of the primary section (10) be ungrooved and not wound and bevelled in sections in such a way that the angle of inclination (.beta.) of the bevelled surfaces (11a, 12a) on the front and rear end faces (11, 12) of the primary section (10) in relation to the longitudinal axis (13) of the motor is selected according to the relation: .beta.=arctan (b/.tau..sub.p) where .beta. is the angle of inclination of the bevelled surfaces (11a, 12a) at the front and rear end faces (11, 12) of the primary section (10), b is the electrically active width of the primary section (10) and .tau..sub.p is the pitch of the poles (21, 22) of the secondary section (20).

Abstract: An electromagnetic actuator includes a bobbin which is disposed between opposite ends of a housing made of a magnetic material and which has a coil wound therearound, a guide sleeve which is fitted to an inner periphery of the bobbin and which is opposed at one end thereof to one of wall ends of the housing and fitted at the other end thereof into a support bore in the other end of the housing, a stationary core fitted into the guide sleeve and caulked to the one end wall of the housing, and a movable core slidably fitted into the guide sleeve and cooperating with the stationary core. In this electromagnetic actuator, an end of the guide sleeve guiding the movable core is placed into close contact with and coupled in a caulked manner to an outer peripheral surface of the stationary core which is caulked and coupled to one of end walls of the magnetic housing.

Abstract: A small diameter linear motor is relatively short in length, and includes a hollow elongated mover, and a stator having a plurality of annular spaced apart stator teeth. Individual electrical coils are wound from individual uninterrupted single wires extending from outside of the assembly in the spaces between the teeth to avoid the need for electrical connections between the coils. The stator assembly and mover are dimensioned to fit within the hollow interior of a ferromagnetic tube. In another form, the linear motor includes a mover and a stator, the stator including a set of coils for producing a series of electromagnetic fields extending at least partially in an axial direction when energized with an electric current and a stator core defining a plurality of spaced-apart transversely disposed coil receiving slots and an annular axially extending mover receiving bore.

Abstract: A can body maker wherein the redraw sleeve is provided with an plurality of air escape openings to provide for the passage of air as the ram moves through the redraw sleeve and wherein the redraw sleeve is attached to the armature of a linear motor which includes a generally cylindrical armature which moves within a surrounding, coaxial stator. The armature includes a plurality of axially spaced apart armature salient pole rings separated by permanent magnet rings. The stator includes a plurality of axially spaced apart stator salient poles which each form a ring radially spaced from and surrounding a portion of the armature. The axial spacing between adjacent stator salient pole rings is one-third greater than the axial spacing between the armature salient pole rings, and an electromagnetic coil extends circumferentially within the stator around the armature between each stator salient pole ring.

Abstract: Electric power converter with load compensation, especially for electrical loads subject to fluctuations in demand for power, such as arc furnaces, welders, etc. An external source of electrical power is applied to a stationary input winding of the converter to produce a movable polyphase magnetic field coupled to an output winding movable at least in part over a limited range relative to the input winding. The movement is resisted by an interposed resilient member adapted to position the output winding to match the output to the input power demand of the load equipment thereby counteracting whatever fluctuations tend to occur in load resistance and current.

Abstract: A current switch is provided which selects and monitors charge and discharge states of a battery pack of a computer system. The current switch provides a current sense signal which is an indication of the current in the battery pack in order that a charge control circuit can monitor the charge state of the battery pack. The gain of the current sense signal is adjusted, depending on whether the battery pack is in a fast charging, trickle charging, or discharging state when the computer system is in a standby mode. Thus, the current switch provides a sufficient current sense signal for accurate current measurements while dissipating little power for the various battery pack charge states.

Abstract: An electric generator for generating an electrical current that comprises a continuous housing containing equally spaced-apart magnets that pass the continuous housing through the center of a plurality of individual coils in a concentric larger outer housing. To enhance the current generated, a plate is inserted between adjacent coils in the larger housing and the magnets are arranged so that opposite poles are adjacent each other. To further increase current generation, the coils may be cooled so as to reduce any resistance therein.

Abstract: A linear motor is operated as an m-phase linear pulse motor or a brushless DC linear motor capable of producing large driving force. The linear motor includes an even number N of salient poles 11, 12, . . . disposed at an equal pitch angle and includes a stator 1 having a plurality of permanent magnet poles disposed on inner peripheral surfaces of the salient poles to have polarities different from each other in the shaft direction and a mover 3 disposed movably in the shaft direction. The salient poles are constituted by pairs of the salient poles adjacent to each other and include m sets of salient pole groups each composed of (N/m) salient poles disposed at an angle of (720 m/N) degrees and windings W1, W2, . . .

Abstract: A linear motor includes a stator 1 having an even number N of salient poles 11, 12, . . . disposed at an equal angle pitch and a mover 3 disposed movably in a shaft direction. The salient poles are constituted by pairs of salient poles adjacent to each other and including m sets of salient pole groups composed of (N/2m) sets of salient pole pairs disposed at an angle of (720m/N) degrees. Windings W1, W2, . . . wound on (N/m)-1 or (N/m)-2 salient poles belonging to each of the salient pole groups are connected to have opposite polarities between the pair of salient poles and are connected to have the same polarity between the salient poles which do not constitute the pair of salient poles and are disposed to interpose the salient pole of the other phase therebetween to constitute phase windings for m phases. Remaining salient poles of the salient pole group are caused to detect a position and a movement direction of the mover 3 as sensor poles S.sub.A and S.sub.B.

Abstract: An actuator having a part that is capable of moving both longitudinally and transversely may include a housing having a longitudinal axis with respect to which the movable actuator part can move within the housing both longitudinally and transversely. The actuator may include electromagnetic windings on a central section of the moveable part and permanent ring magnets disposed thereabout within the housing. The housing may be adapted to allow the longitudinal and transverse movement of the movable part to compensate for rotational movement of pivot mounted linkages connected to first and second ends of the movable part.

Abstract: A superconducting electromagnet for levitation and propulsion of a maglev vehicle running against a rail has a magnetic core having a number of salient poles extending from a surface thereof, thereby forming gaps between adjacent ones of the poles, and facing and in operative proximity with the rail. An excitation coil surrounds each pole and is positioned in the gaps on each side of the pole. A cryostat accommodates the excitation coil and is positioned in the gaps between the conducting coil and the core. A control coil surrounds each pole and is positioned in the gaps on each side of the pole for responding to fast disturbances of short duration with a transient current.

Abstract: A superconducting magnet for a MAGLEV vehicle has flux perturbation shielding rings mounted to the core common with superconducting magnetic coils. These rings resist rapid flux perturbations occurring in the superconducting magnet as a result of normal operational transients. The rings are, in effect, short-circuited coils fabricated from metal. One or more sets of these shielding rings may be employed along the length of the core for achieving flux regulation.

Abstract: A linear pulse motor of the present invention comprises a stator core 10 having salient poles with teeth in the axial direction on the inner peripheral surface, stator windings W2 and W4 wound around each salient pole, and a mover which can move freely in the axial direction in the stator. The mover includes magnetic pole blocks 22 and 34 having teeth in the axial direction on the outer peripheral surface thereof and a permanent magnet 40 magnetized to a predetermined polarity. The aforesaid two magnetic pole blocks are arranged in an opposed relationship with respect to each salient pole via a circumferential gap. The magnetic pole block is magnetized to different polarity from each other by the permanent magnet disposed in the mover core. When the tooth tops of one magnetic pole block are opposed to the tooth tops of the salient pole, the tooth tops of the other magnetic pole block are opposed to the tooth bottoms of the salient pole.

Abstract: An electromagnetic actuator includes a magnetic flux conductive material housing, an electrical current conductive coil, a magnetic flux conductive material stationary core portion, a slideable core portion, and a pair of radially polarized magnetic flux developing elements. The coil is disposed in the housing coextensively adjacent to the housing's interior wall. The core is disposed within the housing and the coil and includes both the magnetic flux conductive stationary core portion and the slideable core portion. The slideable core portion is slideably received on the stationary core portion, and the magnetic flux developing elements are carried on the exterior wall of the slideable core portion in a facing relationship with the coil.

Abstract: A linear driving device includes a hydrostatic gas bearing, a shaft supported by the bearing, and a voice-coil motor for driving the shaft in a direction of movement. The bearing and the shaft are disposed within the voice-coil motor. The device further includes a locking mechanism for constraining the movement of the shaft in its direction of movement. In addition, the voice-coil motor includes a coil assembly having a coil. The coil assembly forms a closed space surrounded by the coil. The coil assembly has a plurality of exhaust holes therein communicating with the outside from the closed space.

Abstract: An electromagnetic actuator is disclosed having a case fabricated of a ferromagnetic material and defining a central axis, a core disposed coaxial with the central axis, and being in slideable engagement within the case. The core includes a first end portion, a second end portion, and a central portion. The actuator further includes magnetic flux developing element mounted coaxial with the central axis and a first and a second electrical current conductor coil. The first coil is mounted in a facing relationship with the first end portion of the core and the second coil is mounted in a facing relationship with the second end portion of the core. The coils are fabricated from a ferromagnetic material and are coaxial with the central axis. The coils have a cross-sectional length in a direction perpendicular to the central axis and a width of insulating space between the turns of the coil in a direction parallel to the central axis.

Abstract: The electric machine, preferably a three-phase generator (10) for vehicles with a liquid-cooled, pot-shaped metal housing (20) includes two three-phase systems arranged in the house and situated one after the other in the axial direction, a drive shaft (13) received in the base of the metal housing on one end and in a bearing cover (18) on the drive end. For a compact connection of the two three-phase systems and exciter systems with rectifier units and regulators the electrical connections of the three-phase and exciter windings (31, 32; 14, 15) are received in the bearing cover (18) so that they are electrically connected with positive and negative diodes (44, 45) of the rectifier units arranged externally on the bearing cover (18) and with the regulators and connection terminals (22) of the machine via printed circuit boards (65, 80).

Abstract: In an electric motor (11) with at least one winding (14) through which an electric current flows to produce a relative movement between a stator portion and a reaction portion, with at least one magnet (12), the field of which passes through the winding, and with at least one body (20) of ferromagnetic material which is arranged in the fields of the magnet and winding in order to achieve the minimum structural configuration with the maximum outputtable force, it is provided that the winding is immovably connected to the magnet at least in the direction of the relative movement and that the body of ferromagnetic material is mounted movably relative to the winding and the magnet in the direction of the relative movement, and has an air gap (22) which extends transversely to said direction of relative movement and which is so arranged that the magnetic flux in the winding alters as a result of the relative movement of the air gap with respect to the winding and the magnet.

Abstract: A vertically reciprocating and substantially constant power drive unit, including pumping equipment situated at the bottom of a string of drive rods is provided. The drive unit comprises a linear electric motor whose field inductor and whose armature are constituted by two coaxial cylindrical parts, one of which is coupled to the top end of the drive rods and is movable relative to a stationary structure. A balancing device exerts a force on the moving equipment constituted by the pumping equipment, the rods, and the motor coupled thereto, which force is equal and opposite to the sum of the weight of the moving equipment plus one-half the weight (H/2) of the load.

Abstract: An electromagnetic actuator includes a magnetic flux conductive material case, an electrical current conductive coil, a magnetic flux conductive material core, and a pair of radially polarized magnetic flux developing elements. The coil is disposed in the case coextensively adjacent to its interior wall. The core is movably received within the chamber with motion of the core occurring between the first end and the second end of the case such that a first region of the core traverses the coil between its first end and its midpoint, and a second region of the core traverses the coil between its second end and its midpoint. A first one of the magnetic elements is carried by the first region and a second one of the magnetic elements is carried by the second region so that magnetic flux across the coil between the first region and the case is in a first direction, and magnetic flux across the coil between the second region and the case is in a second direction.

Abstract: A new and improved linear motor and method of using it for producing a sufficient reciprocating thrusting action to enable well fluids be pumped through the production tubing of a well to the ground surface. The linear motor includes a mover and a stator, said stator including a set of coils for producing a series of electromagnetic field extending at least partially in an axial direction when energized with an electric current and a stator core defining a plurality of spaced-apart transversely disposed coil receiving slots and an annular axially extending mover receiving bore. The mover includes an elongated member mounted telescopically reciprocatively within the mover receiving bore and a plurality of permanent magnets interleaved with low reluctance spacers for helping to reduce core flux density in order to improve overall motor performance.

Abstract: Upon operation of an erasure key for erasing a printed character, a correction ribbon is moved in an erasure position according to rotation of a motor, and then, the motor is continuously rotated forward at a current I2 larger than a current I1 in a print operation. Therefore, a print hammer is accelerated to a speed V2 higher than a speed V1 in the print operation, to strike a platen at the speed V2. In the erasing operation, no pressing operation is performed after the stroke. Rather, the print hammer is immediately returned and the ink is removed.