Patents Examined by Donovan F. Duggan
  • Patent number: 4845392
    Abstract: A linear actuator is a hybrid in that movement of the armature is influenced by the field of permanent magnets and the field of a coil when it is energized by direct current. The coil is fixed in a ferromagnetic shell and a pair of permanent magnets are fixed in the shell axially of the coil. The armature has a reduced diameter tip or end which is influenced by the magnets when the coil is deenergized and which enables the force on the armature to remain generally uniform over the working stroke of the armature. The linear actuator is shown operating a sleeve valve spring biased to closed position and opened relative to the metering cone by application of direct current to the coil. The effective magnitude of the current determines how much the valve opens.
    Type: Grant
    Filed: March 10, 1983
    Date of Patent: July 4, 1989
    Assignee: Eaton Corporation
    Inventor: Alan L. Mumbower
  • Patent number: 4797591
    Abstract: A link suspension permitting limited rotation of a rotor in response to a magnetic control field uses a permanent magnet and support means having two contacting narrow concave curvilinear surfaces.
    Type: Grant
    Filed: November 5, 1986
    Date of Patent: January 10, 1989
    Inventor: Edward C. Streeter
  • Patent number: 4771201
    Abstract: A thermionic energy conversion method and apparatus is disclosed that eliminates or substantially reduces deficiencies caused by space charge or thermal radiation losses from the emitter to the collector. The method and apparatus uses an acceleration electrode having an aperture and disposed in the space between the emitter and collector. A high positive voltage is applied to the acceleration electrode to generate a positive electrostatic field. The shape of the facing surfaces of the emitter and collector and the shape of the acceleration electrode shape the electrostatic field to cause boiled-off electrons from the emitter to be accelerated and converged so that they all pass through the aperture without impinging on the acceleration electrode.
    Type: Grant
    Filed: September 17, 1980
    Date of Patent: September 13, 1988
    Assignee: Intelsat
    Inventor: Bernard A. Free
  • Patent number: 4761573
    Abstract: A linear DC motor adapted for driving a positioning table having a frame and a table displaceable in a linear direction has a toothed assembly affixed to one element thereof and an array of permanent magnets facing the toothed assembly mounted on the other element. Coils wound around the teeth of the toothed assembly and appropriately energized by DC produce a linear force which is effective to displace the table in a desired direction. When used with a position sensor and an appropriate control system, the table is controllable to a desired position. A set of brush members depending from the table contact a developed linear slip ring track for energizing the coils and for switching polarity of voltage to the coils at appropriate locations. In an embodiment where the coils are stationary on the frame and the magnets are disposed on the table, a power pickup arrangement movable with the brush members is incorporated into the brush and developed slip ring apparatus.
    Type: Grant
    Filed: August 25, 1986
    Date of Patent: August 2, 1988
    Inventor: Anwar Chitayat
  • Patent number: 4758751
    Abstract: A thin type DC brushless motor comprises a permanent magnet rotor, a stator core which is arranged concentrically with the rotor, and stator coils which are wound on the stator core. The stator core is so configured as to include a ring-shaped core portion which surrounds the permanent magnet of the rotor and which has a thickness substantially equal to the axial thickness of the permanent magnet, and a plurality of coil winding core portions which extend radially outwardly from the outer periphery of the ring-shaped core portion, which have a thickness less than the thickness of the ring-shaped core portion and which serve to dispose the stator coils thereon. The ring-shaped core portion is formed with notches so as to leave salient interpole portions disposd upon sides of the respective coil winding core portions as viewed in the rotating direction of the rotor, on front and rear surfaces of the coil winding core portions as viewed in the direction of the permanent magnet.
    Type: Grant
    Filed: August 29, 1986
    Date of Patent: July 19, 1988
    Assignee: Tobishi Industries Ltd.
    Inventors: Toshiro Hosoya, Rintaro Kaneeda
  • Patent number: 4754178
    Abstract: A two phase stepper motor having a rotor shaft with a multi-pole rotor and a stator assembly in magnetic flux relationship with the rotor. The stator assembly includes a plurality of sequentially stacked laminations which are each provided with eight stator poles with each immediately successive stator pole having an opposite phase and each being at a index spacing from the immediately adjacent lamination. The stepper motor also contains a multi-phase winding for energizing the stator poles to operate the rotor in successive discrete steps. The stepper motor housing includes first and second end pieces having a pair of triangular cross-section members forming notches therebetween on a first pair of oppositely disposed corners which receive and retain an abutment post on a second pair of oppositely disposed corners from the opposite end piece thereby interlocking the first and second end pieces relative to one another.
    Type: Grant
    Filed: August 12, 1987
    Date of Patent: June 28, 1988
    Assignee: MCS, Inc.
    Inventor: Richard J. Kavanaugh
  • Patent number: 4752706
    Abstract: In accordance with the invention the magnetic friction force is overcome by a rolling motion whereby there is physical contact between the field magnets and the core. As experiments show, reversal of magnetic flux polarity on and in a ferromagnetic object was 14 times less difficult to realize by such rolling motion. Because full contact is realized between field magnets and winding cores, a greater flux density is produced by the magnetic circuit. The above concept introduces a whole new breed of distinctly different rolling motion electricity generators.
    Type: Grant
    Filed: March 28, 1986
    Date of Patent: June 21, 1988
    Inventor: Leslie G. Meszaros
  • Patent number: 4752708
    Abstract: An apparatus for supporting conductor bars of an end winding of a stator winding of an electric machine having a lamination stack includes pressure plates holding the lamination stack together, support angles supporting the conductor bars in the vicinity of the end winding, a support ring being directly axially adjacent the pressure plate and having an inner periphery, the support angles having radially outer surfaces braced against the support ring, the support angles being guided and partially disposed in radially extending slots formed in the pressure plates, and spacers in the shape of ring segments resting on the inner periphery of the support ring and preventing tangential deflection of the support angles.
    Type: Grant
    Filed: March 25, 1987
    Date of Patent: June 21, 1988
    Assignee: Brown, Boveri & Cie AG
    Inventors: Kurt Jager, Peter Ehrt
  • Patent number: 4751437
    Abstract: A wide bandwidth linear motor system suitable for high performance applications such as driving the tuning plunger of a magnetron oscillator. The linear motor includes a coil assembly with a structure which suppresses secondary resonances, thereby permitting the linear motor to be used in a wide bandwidth servo control loop. The coil assembly includes a cylindrical coil support, a bushing coaxial with the coil support for attachment to the linear motor shaft, a plurality of radial ribs connecting the coil support to the bushing and a coil having multiple turns wound circumferentially around the coil support. The coil support is subdivided by axial gaps into at least two separate coil support elements, each connected by a radial rib to the bushing. Resonance of the coil support and the coil is suppressed by the separate coil support elements and the lossy connection therebetween.
    Type: Grant
    Filed: March 26, 1986
    Date of Patent: June 14, 1988
    Assignee: Varian Associates, Inc.
    Inventor: William A. Gerard
  • Patent number: 4751416
    Abstract: A synchronous servomotor has a slotted stator core (7) with windings placed in the slots (8) thereof, and a rotor core (5) having magnetic poles formed by permanent magnets (6) attached to the core (5). For the purpose of reducing the reluctance torque, at least certain poles are displaced from the positions which correspond to fully uniform distribution of the poles around the rotor core through a displacement angle which corresponds to a fraction of the slot pitch in the stator core. Mutually, different poles are advantageously displaced from the positions corresponding to fully uniform pole distribution through mutually different angles, although in a manner such that the magnetic forces acting on the rotor core balance one another.
    Type: Grant
    Filed: April 11, 1986
    Date of Patent: June 14, 1988
    Assignee: AB ELMO
    Inventor: Vilmos Torok
  • Patent number: 4749921
    Abstract: An armature for a permanent-magnet linear motor is made up of a set of coils retained in a flat armature plate. The armature plate is of non-magnetic material. In one embodiment, the armature plate is of aluminum having parallel grooves machined in one surface to receive the straight runs of the coils. An aluminum plate covers the grooves to create a reinforcing box-like structure. In a second embodiment, the armature plate is dispensed with and the coils are integrally cast into a resin jacket. A further embodiment employs a serpentine cooling coil for supporting the coils prior to casting the resin and for dissipating coil heat during operation.
    Type: Grant
    Filed: July 21, 1986
    Date of Patent: June 7, 1988
    Inventor: Anwar Chitayat
  • Patent number: 4749891
    Abstract: A non-linear electromagnetic vibration device including a first vibration part and a second vibration part. A non-linear bellows plate spring set is connected between the first and second vibrating parts. Each spring set is composed of sequentially coupled bellows plate springs, and each plate spring is elastic according to a predetermined particular waveform and has a plate structure of a predetermined shape. The waveform is selectable among many including portions of an exponential curve. The plate structure of each spring is rectangular with an edge which is straight, convex, or concave in contour. The first vibration part of the device is rigidly connected to a corresponding section of each spring set and the second vibration part of the device is coupled to a different or second area of each spring set.
    Type: Grant
    Filed: March 12, 1986
    Date of Patent: June 7, 1988
    Inventor: Cao P. Sheng
  • Patent number: 4749893
    Abstract: This invention is an engine with reciprocating piston slidingly mounted within a cylinder and connected to a rotatable shaft. The piston is driven back and forth within the cylinder by a pair of electromagnets to obtain rotary power. A secondary winding around one of the electromagnets produces an alternating current. An anti-arc relay is also provided to prevent burning of the high voltage contacts.
    Type: Grant
    Filed: July 14, 1986
    Date of Patent: June 7, 1988
    Inventor: Billy D. Reynolds
  • Patent number: 4748356
    Abstract: An electric fuel pump is provided with an insulative holding member 20 for holding choke coils 16 and connecting portions 23 between the choke coils and lead wires (14) as well as between the choke coils and brushes 10, to be mounted in the interior of a pump frame 1. In this electric fuel pump, the insulative holding member 20 holds and fixes the choke coils 16 and the connecting portions around the same, thereby to protect the choke coils 16 and the nearby connecting portions against vibration and shocks applied to the fuel pump. The holding member 20 also insulates conductive parts so that the same are not in contact with a housing 1 of magnetic material or the like, thereby to improve insulativity.
    Type: Grant
    Filed: January 29, 1987
    Date of Patent: May 31, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tetsuo Okashiro, Shingo Iwai, Ryozo Suzuki
  • Patent number: 4748360
    Abstract: A rotor for a synchronous motor, having a plurality of first magnetic poles formed by a plurality of permanent magnets respectively and disposed at practically equal circumferential intervals on the outer circumference of a yoke fixed to a rotatable motor shaft, and a second magnetic pole projecting radially from the yoke adjacently to each first magnetic pole and the second magnetic pole wherein the shape of the pole face of each first magnetic poles are in a circular arc and the shape of the pole face of each of second magnetic pole is determined by a given equation so that the magnetic flux distribution established by a pair of the first magnetic pole and the second magnetic pole is substantially equivalent to a sinusoidal magnetic flux distribution in the sweeping effect by the armature coils of each phase of the stator.
    Type: Grant
    Filed: April 24, 1987
    Date of Patent: May 31, 1988
    Assignee: Fanuc, Ltd.
    Inventors: Shigeki Kawada, Yoichi Amemiya, Masatoyo Sogabe, Noboru Iwamatsu
  • Patent number: 4748354
    Abstract: A rotor for a salient-pole machine comprises a rotor rim rotatable with a rotary shaft and magnetic poles fixedly connected at prescribed intervals to the rotor rim on its outer periphery. Axially extending ventilation grooves are formed on the rotor rim between respective adjacent poles. The pole is connected to the rotor rim by means of a dovetail joint consisted of a dovetail groove on the rotor rim and a dovetail tenon on the bottom of the pole. The ventilation groove has a sectional profile in the perpendicular to the rotary shaft which is defined by connecting necessary lengths required in the material strength of groups of lines respectively originating from the corners of the dovetail groove.
    Type: Grant
    Filed: October 7, 1987
    Date of Patent: May 31, 1988
    Assignee: Hitachi, Ltd.
    Inventor: Hisashi Toshima
  • Patent number: 4746827
    Abstract: A rotor for an electric motor including an iron core having collar portions at both end portions thereof, and a magnet placed on the outer periphery of said iron core. The magnet is held at both end portions thereof between the collar portions.
    Type: Grant
    Filed: February 17, 1987
    Date of Patent: May 24, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Izumi Ochiai, Hideo Hashida, Yoshio Asahino, Nobuhiko Yokota
  • Patent number: 4745312
    Abstract: In a stepping motor having a stator and a rotor, the stator is made of a laminated iron core of a cylindrical shape having a plurality of slots formed around the periphery at a constant pitch. Coil windings concentrately wound are inserted in the slots, and permanent magnets of a planar shape are adhere around the surface of the iron core, thereby providing stator magnetic poles. The rotor on the other hand is made in the form of a circular disk at least a part of which is made of a magnetic material. A number of teeth are formed around the peripheral portion at a constant pitch thereby providing rotor magnetic poles which are positioned in opposition to the stator magnetic poles with a predetermined air gap maintained therebetween.
    Type: Grant
    Filed: December 16, 1986
    Date of Patent: May 17, 1988
    Assignee: Kabushiki Kaisha Yaskawa Denki Seisakusho
    Inventor: Nagahiko Nagasaka
  • Patent number: 4745316
    Abstract: In a submersible motor, a liquid is filled into its rotor chamber, a shaft to which a rotor is fixed is supported on a frame by sleeve bearings, and a diaphragm for controlling the pressure within the rotor chamber is disposed at the lower portion of the frame. Chambers communicating with the rotor chamber, are disposed above an upper sleeve bearing and the chambers accomodate a reserve liquid having a volume larger than that of the diaphragm. Therefor, even if the pressure within the rotor chamber rises and the diaphragm is deformed, the upper sleeve bearing is continuously filled with the liquid, thereby enabling continuous lubrication and cooling.
    Type: Grant
    Filed: April 21, 1986
    Date of Patent: May 17, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Ryoichi Nakashima, Yasuro Suzuki, Masato Kobayashi
  • Patent number: 4743786
    Abstract: This rotational position detection device comprises a stator section including primary and secondary windings and a rotor section disposed in such a manner that it is capable of performing relative rotational displacement with respect to the stator section. A conductive substance portion is provided in the form of a predetermined pattern. The amount of flux passing through the conductive substance portion of the rotor section changes in accordance with a relative rotational position of the rotor section with respect to the stator section and therefore an eddy current flows through the conductive substance portion. Reluctance is caused to change by a loss due to this eddy current and a secondary output signal corresponding to the rotational position is produced in the windings of the stator section. The pattern of the conductive substance portion can be formed easily by using electro-plating or other surface processing technique.
    Type: Grant
    Filed: November 19, 1985
    Date of Patent: May 10, 1988
    Assignee: Kabushiki Kaisha SG
    Inventors: Wataru Ichikawa, Yuji Matsuki, Takeo Maruyama