Impedance Devices Patents (Class 310/72)
  • Patent number: 6670733
    Abstract: Technique for reducing bearing current discharges in a system by increasing the surface area between the shaft and the frame of the system and thereby increasing the rotor to frame capacitance.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: December 30, 2003
    Assignee: Reliance Electric Technologies, LLC
    Inventor: Michael J. Melfi
  • Patent number: 6580194
    Abstract: A motor includes an electrically conductive yoke housing and a noise limiter circuit. The yoke housing is configured in an oblate cylindrical cup form having a couple of opposed flat side walls and a couple of opposed arcuate side walls that join opposed lateral edges of the flat side walls together. The noise limiter circuit includes choke coils. Each choke coil is arranged adjacent to a corresponding corner of the yoke housing located between a corresponding one of the flat side walls and a corresponding one of the arcuate side walls in such a manner that each choke coil extends substantially parallel to a central axis of the yoke housing.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: June 17, 2003
    Assignee: Asmo Co., Ltd.
    Inventors: Nobuo Mizutani, Wataru Kanou
  • Publication number: 20020047366
    Abstract: A suppressor for a device for connecting an electric motor has a varistor and a capacitor connected in parallel for providing suppression for the electric motor. The suppressor has particularly small dimensions compared with a capacitor exhibiting a comparable suppression strength. For the purposes of providing suppression for electric motors used for fuel pumps, the dimensions of the suppressor are fundamentally independent of its power and the level of design complexity required for mounting suppressors on the electric motor with a different power is particularly low.
    Type: Application
    Filed: May 4, 2001
    Publication date: April 25, 2002
    Applicant: Mannesmann VDO AG
    Inventors: Uwe Allendorf, Jurgen Zoll
  • Patent number: 6359353
    Abstract: A submersible motor unit is used to drive a pump and is submerged with the pump in liquid (water). The motor unit includes a tubular housing member and a tubular inner member which is enclosed by and disposed in a coaxial relationship with the tubular housing member. A stator is disposed in a stator chamber formed between the tubular inner member and the tubular housing member. A rotor is disposed in a rotor chamber disposed within the inner member. End walls close opposite ends of the tubular housing member and the tubular inner member. An annular capacitor is disposed in the stator chamber in an axially spaced apart relationship with the stator. The capacitor extends around the rotor chamber. A body of potting compound is disposed in the stator chamber and at least partially encloses the stator and the capacitor.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: March 19, 2002
    Assignee: F. E. Myers division of Pentair Pump Group
    Inventor: Jack T. Bevington
  • Patent number: 6300696
    Abstract: A miniature electric motor has a tubular housing with a closed end and an open end. The open end is closed by an end cap assembly. The end cap assembly comprises an end cap supporting two motor terminals and two brush assemblies. A chip capacitor is connected between the motor terminals. The positive motor terminal is connected to the positive brush assembly by a choke and the negative motor terminal is connected to the negative brush assembly by a PTC. The negative motor terminal is also connected to the motor housing by an earth strap which is nipped between the end cap and the motor housing.
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: October 9, 2001
    Assignee: Johnson Electric S.A.
    Inventor: Ben To Fan Wong
  • Publication number: 20010015583
    Abstract: A converter for an electric motor or transformer, the converter being comprising a connection box having passages for electrical conductors and having a semiconductor electronic module removably fixed to the connection box. The electronic module has a radiator-forming box that is open at one end, at least one electronic card at least partially embedded in a resin cast inside said radiator-forming box, and at least one connector emerging from the resin. The opening of the radiator-forming box enables it to be fitted to the connection box. The connection box has at least one window giving access to the connector(s) of the electronic module.
    Type: Application
    Filed: February 6, 2001
    Publication date: August 23, 2001
    Inventors: Serge Petit, Jean-Marc Petillon, Alain Buisson, Regis Giraud
  • Patent number: 6218749
    Abstract: An electromechanical device comprises a stator and a rotor which is capable of rotating relative to the stator. The rotor has a sensor embedded therein. In a preferred embodiment, the sensor is disposed within a plurality of laminations that are stacked one on top of another. For example, one of the plurality of laminations may be a sensor lamination, in which case the sensor is at least partially disposed within a cavity formed in the sensor lamination. Advantageously, the sensor may be used to directly measure rotor-associated operating conditions, such as rotor current (including the magnitude, frequency and phase of the rotor current), rotor fatigue, rotor temperature, rotor airgap, rotor flux and rotor torque. The sensor is especially well-suited for measuring current in the rotor of an induction motor.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: April 17, 2001
    Assignee: Reliance Electric Technologies, LLC
    Inventors: Thomas A. Nondahl, Perry A. Delvecchio
  • Patent number: 6075305
    Abstract: A dynamo-electric machine satisfies an expressionR.sub.eq .gtoreq.(.rho..sub.0 .multidot.(r1*.tau.)/(S/3))*(2.5)where .rho..sub.0 (.OMEGA..multidot.m) is the resistivity of armature coil, S (m.sup.2) is the cross-sectional area of the conductor portions thereof, r1 (m) is radius of rotation of the connecting portions between equalizers and armature circuits, namely the armature coil, risers, or commutator segments, .tau. (rad) is the pitch of pole pairs, and R.sub.eq (.OMEGA.) is the resistance value of the equalizer.
    Type: Grant
    Filed: August 30, 1999
    Date of Patent: June 13, 2000
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akihiro Daikoku, Toshinori Tanaka, Kiyohide Okamoto, Shuji Isono, Akihiko Imagi, Yoshio Yoshikuwa, Masafumi Okazaki, Kyouhei Yamamoto
  • Patent number: 6057615
    Abstract: A bracket for attaching a capacitor with an engagement portion to a motor having therein a keyhole with a rectangular portion and a circular portion. The bracket includes a first semicylindrical member having a first downwardly extending portion and a first hinge portion and a second semicylindrical member having a second downwardly extending portion and a second hinge portion. The first hinge portion and second hinge portion are engageable to form a hinge with an axis about which the semicylindrical members are pivotable to open and closed positions. When in the open position, the semicylindrical members permit the capacitor to be removed from the bracket. When in the closed position, the semicylindrical members define a cylinder having an axis and including a capacitor engagement portion for engaging the capacitor, thereby retaining the capacitor in the bracket.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: May 2, 2000
    Assignee: A. O. Smith Corporation
    Inventor: Norman R. Long
  • Patent number: 6037686
    Abstract: Each torque-producing phase current of a multi-phase motor is passed through a filter which includes an R/C shunt to ground and a series, current-compensated choke. Each choke has a winding in series with each phase so that the net current generated by phase currents in the windings is zero, and therefore the net flux generated by phase currents in the highly permeable core of the choke is zero at all times. However, there is significant inductive reactance created by the non-counterbalanced motor leakage currents, which prevent leakage currents from circulating through the motor. Thus, torque-producing motor currents can accurately be measured for feedback, without pollution from leakage currents. LEM current transducers allow use of small, proportional currents in the measuring and suppress inter-phase coupling.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: March 14, 2000
    Assignee: Otis Elevator Company
    Inventors: Uwe Schonauer, Robert Oesterle, Christoph M. Ernecke
  • Patent number: 5903072
    Abstract: An electric motor input circuit including a leadless capacitor which reliably and efficiently provides the highest possible level of RFI suppression and the greatest reduction in conducted voltage transients. The assembly includes a capacitor having no solid lead wires and no epoxy coating which is snap-fit into the motor power circuit so that one of the capacitor plates is in pressing engagement with one of the input terminals and the other of the capacitor plates is in pressing engagement with a conducting tab. The conducting tab is formed on the other of the input terminals, and the capacitor is, therefore, connected between the terminals without the use of solid capacitor leads.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: May 11, 1999
    Assignee: Fasco Industries, Inc.
    Inventor: Patrick D. Phillips
  • Patent number: 5821652
    Abstract: Damaging shaft voltages in an induction motor are prevented by an electrostatic shield between the stator winding structure and the rotor structure. The electrostatic shield is held at the same potential as the grounded motor frame. The shield includes an aluminum strip in each winding slot, with one strip in firm engagement with the stator core. The strips are flat strips and extend beyond both ends of the slot to the outer end turns of the stator winding. This places that one strip at the ground reference potential of the motor frame. All strips are connected to the one grounded strip by an end ring. All others are insulated from the core. The strips are connected at only one end to avoid a squirrel cage winding affect.
    Type: Grant
    Filed: August 28, 1996
    Date of Patent: October 13, 1998
    Assignee: Marathon Electric Manufacturing Corporation
    Inventor: David B. Hyypio
  • Patent number: 5751082
    Abstract: A high starting torque induction motor with simultaneously reduced starting current adapted to be associated with a drive having a high load torque on starting that includes a stator, a rotor, a first end ring fixed on said rotor, a second movable end ring associated with said rotor and having a lower electrical resistance than the first ring, and a centrifugal device associated with the second ring and operable upon the rotation of the rotor at a predetermined speed such that, when the motor is electrically energized, the high resistance of the first ring produces a high starting torque at reduced starting current, and when the motor achieves a predetermined speed, the second ring is moved into engagement with the first ring reducing the effective resistance and permitting normal operation of the electric motor.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: May 12, 1998
    Assignee: Vickers, Incorporated
    Inventor: Umesh C. Gupta
  • Patent number: 5731653
    Abstract: A brushless exciter diode wheel system includes a diode wheel and an electrical connection apparatus that is coupled to the diode wheel. The electrical connection apparatus includes a fuse support block, a diode support block, and a connector for electrically connecting the fuse support block to the diode support block. This connector permits the system to carry at least about 2000 amps of current, which is far in excess of the current capacity of conventional systems of this configuration.
    Type: Grant
    Filed: October 17, 1996
    Date of Patent: March 24, 1998
    Assignee: Westinghouse Electric Corporation
    Inventors: Michael Joseph Rasinski, Robert Ervin Ashley, III
  • Patent number: 5616978
    Abstract: An electroconductive material has at least one portion in which the electrical resistance varies continuously along a gradient. Accordingly, since the material is not formed by directly bonding different elements, it does not have a weak joint portion. Further, since other material characteristics besides electrical resistance also vary along a gradient, for instance, when the material is used at a high or low temperature, a large thermal stress does not generate at an interface between different elements of the material due to a difference of thermal expansion coefficients of such elements. A motor uses the above electroconductive material as a conductor provided in a plural slots. Consequently, starting characteristics of the motor are improved due to the skin effect, and internal stress of the motor due to the thermal expansion of the conductor is decreased. Moreover, the reliability of the motor is improved.
    Type: Grant
    Filed: March 5, 1993
    Date of Patent: April 1, 1997
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Kanai, Masashi Takahashi, Yoshiyasu Itoh
  • Patent number: 5550415
    Abstract: A vehicular alternating current generator having a base 1 attached with at least one of a brush holder 2 and a voltage regulator and a condenser 5 attached to the base for preventing an electric noise, wherein a main body of the condenser is isolated from an outside atmosphere by a resin 13 and is disposed in a condenser accommodating body 11 while connecting leads 5a of the condenser are exposed to the outside of the condenser accommodating body and a holding portion 10 is formed in the base for accommodating the condenser accommodating body.
    Type: Grant
    Filed: May 10, 1994
    Date of Patent: August 27, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Katsumi Adachi, Kyoko Kurusu
  • Patent number: 5548169
    Abstract: A motor with a built-in capacitor is proposed. The capacitor is formed into a ring so that a shaft of the motor penetrates a center portion of the capacitor and is disposed in the motor so that the shaft of the motor penetrates the center portion. The capacitor is mounted at the same time as the motor is mounted and the mounting work of the capacitor is easy. The external shape of the motor itself is the same as that of a conventional motor. The whole structure of the motor is compact as compared with the conventional motor. The motor can be applied to a motor with a capacitor directly connected to a gear mechanism such as a transmission.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: August 20, 1996
    Assignee: Oriental Motor Co., Ltd.
    Inventors: Takao Iwasa, Takaji Kambayashi
  • Patent number: 5495132
    Abstract: A brushless DC motor in which increased rotor resistance is used to facilitate very frequent reversals. The rotor endcap is thinned down to the point where the resistance seen by the path of the current loop through one of said endcaps, is at least one-half as much as the resistance seen by the portion of said current loop which flows along the length of one of said rotor bars.
    Type: Grant
    Filed: January 3, 1994
    Date of Patent: February 27, 1996
    Assignee: SGS-Thomson Microelectronics, Inc.
    Inventors: Christopher J. Shultz, Michael D. Shultz, Gil F. Schultz
  • Patent number: 5493158
    Abstract: A bracket of the present invention is for use with a capacitor motor having a stator and at least one end shield. The motor end shield has a side wall the bottom of which is spaced axially upwardly and radially outwardly from an axially outer face of the stator to define a gap. The bracket has a base, a pair of legs extending upwardly from the base to snappingly receive the capacitor, and a tab which is received in the gap to secure the bracket to the motor without the use of fasteners.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: February 20, 1996
    Assignee: Emerson Electric Co.
    Inventor: Nicholas R. Daniels
  • Patent number: 5479057
    Abstract: A current modulation device embodying a fixed stator which has at least one annular signal track with an axis and whose potential varies circumferentially on a periodic basis as well as a plurality of collector tracks which are connected to a respective output terminal; and a rotor adapted to be coupled to a rotary driving body rotating about the axis which has output brushes of equal number as the collector tracks and each adapted to sweep one respective collector track, as well as input brushes of equal number as the output brushes, each input brush being electrically connected to a respective output brush and being adapted to sweep the annular signal track, the input brushes being so arranged as to take, during the rotation of the rotor with respect to the stator, potentials presenting a given electric phase-shift.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: December 26, 1995
    Assignee: Aerospatiale Societe Nationale Industrielle
    Inventors: Rinaldo Rossi, Jean-Yves Guerrero
  • Patent number: 5294852
    Abstract: A laminated, metal-polymer-metal PTC resistor (8) is held in the end cap (2) of an electric motor. Substantially parallel opposed surfaces (9 and 10) of the PTC resistor (8) are engaged by electrically conductive members (11 and 12) which are respectively connected to one of the brushes (5) and one of the motor terminals (6) so that the supply of electricity is interrupted when the PTC resistor (8) is heated above a predetermined temperature as a result of excessive current flow. The PTC resistor (8) is supported against movement perpendicular to the substantially parallel opposed surfaces (9 and 10), at least in one direction, and therefore independently of at least one of the contact members (11 and 12) so that, at most, only one of the contact members (11 and 12) is needed for supporting the PTC resistor (8). Both contact members (11 and 12) can therefore make point contact with the PTC resistor (8) and this improves operation by inhibiting the conduction of heat to or from the PTC resistor (8).
    Type: Grant
    Filed: April 27, 1992
    Date of Patent: March 15, 1994
    Assignee: Johnson Electric S.A.
    Inventor: Gary Straker
  • Patent number: 5243243
    Abstract: Apparatus and method are disclosed for use with a starting circuit to prevent start-up of an electric motor when the motor's insulation resistance is of a value below a selected insulation resistance limit value below which the motor should not be energized. The selected limit value is a selected percentage of a known maximum value. A variable resistance device, such as a potentiometer, having first and second adjustable resistance portions is adjusted so that the adjusted resistance value of the second portion is of the same percentage of the total resistance value of the first and second portions as the selected percentage discussed above. A DC test voltage of a known value is applied to the motor's insulation resistance to cause a test current to flow therethrough. The test current is directed to flow through the second resistance portion to develop a test voltage.
    Type: Grant
    Filed: November 12, 1991
    Date of Patent: September 7, 1993
    Inventor: J. Leroy Andrews
  • Patent number: 5243247
    Abstract: A brush bridge assembly for an electric motor an electrically insulating carrier body having a base plate having opposite inner and outer surfaces and a generally circular perimeter; and a cylindrical side wall extending axially from the perimeter of the base plate. The brush bridge assembly further has a plurality of brush guides supported on the inner surface of the base plate; a carbon brush supported in each brush guide for a radial displacement relative to a central axis of the carrier body; a spring connected to each carbon brush for urging the carbon brush radially inwardly; supporting elements mounted on the inner surface of the base plate in a uniform distribution; heat generating electric components and fixed contact terminals held in the supporting elements.
    Type: Grant
    Filed: June 29, 1992
    Date of Patent: September 7, 1993
    Assignee: Licentia Patent-Verwaltungs-GmbH
    Inventor: Andreas Schmidt
  • Patent number: 5231322
    Abstract: A brush device, comprising a brush holder and a brush assembly, for providing electrical contact with a moving part while suppressing electrical noise generated during the interaction of the brush device with the moving part. The brush holder includes a housing adapted to receive a brush assembly within the housing, and noise suppression arrangement, mounted on the housing and electrically connected to a brush assembly, for suppressing electrical noise generated during the interaction of the brush assembly and the moving part by providing an inductive impedance in the electrical path of the brush assembly. The brush holder may further include a connector cap, electrically connected to the noise suppression arrangement, adapted to provide a mating connection between the noise suppression arrangement and an external connector. The brush assembly is positioned within the housing such that sliding electrical contact is made with the moving part.
    Type: Grant
    Filed: August 7, 1992
    Date of Patent: July 27, 1993
    Assignee: Ford Motor Company
    Inventors: Monica Richards, Robert J. Mohan
  • Patent number: 5214335
    Abstract: A brush and slip ring apparatus for an alternating current generator. A brush assembly is secured to a rotor shaft of the generator to rotate therewith. The brush assembly includes two axially spaced brushes that are pivoted to a brush support that is secured to the shaft. When the shaft is rotated, the brushes move outwardly away from the shaft due to centrifugal force. The brushes respectively engage two axially spaced fixed slip rings that surround the brush assembly. The brushes are maintained engaged with the slip rings due to centrifugal forces developed by the pivotally mounted brushes. The brushes are connected to a field coil of the rotor of the generator.
    Type: Grant
    Filed: July 7, 1992
    Date of Patent: May 25, 1993
    Assignee: General Motors Corporation
    Inventors: Gregory A. Phillips, Raymond Prater, Thomas C. Ruth
  • Patent number: 5196747
    Abstract: In the case of a universal electric motor for any kind of drive, with a stator package, a rotatably mounted rotor with commutator, as well as end shields on both sides that also constitute the bearings for the rotor and a switching ring that can be rotated through predetermined angular amounts and carries the (carbon) brushes, it is proposed to insert into the end shield A a closely fitting anchor block that serves for locking together the two end shields with the intervening stator package; further, the switching ring can be mounted on an external annular end face of the end shield B that also carries the switching strips or switching rails needed for switching between clockwise and counter clockwise rotation, complete with contact areas situated in the plane of the annular end face and suitable for axial contacting, the said contact areas making contact with other axial contact areas on the switching ring to establish connections with the carbon brushes.
    Type: Grant
    Filed: July 11, 1990
    Date of Patent: March 23, 1993
    Assignee: Kress-Elektrik GmbH & Co., Elektromotoren Fabrik
    Inventors: Willy Kress, Alfred Binder
  • Patent number: 5192887
    Abstract: A multi-speed electric motor (1) has a main electrical winding (3) and an auxiliary electrical winding (5) connected in parallel. One additional electrical winding (21) is connected in series with the parallel connected main and auxiliary windings, and another additional electrical winding (23) is connected in series with this third winding. A temperature sensitive resistive element (25) is connected in parallel with at least one of the additional electrical windings. The resistive element improves the motor's starting torque when one or more additional windings are initially connected in the motor circuit as it is started.
    Type: Grant
    Filed: September 23, 1991
    Date of Patent: March 9, 1993
    Assignee: Emerson Electric Co.
    Inventor: Kenneth R. Theis
  • Patent number: 5157294
    Abstract: A miniature motor driven by a full-wave or half-wave rectified power source, having a stator of a two-pole field system using a permanent magnet as magnetic poles, a rotor comprising a winding wound on a four-pole core, and noise-suppressing capacitors disposed between adjoining core arms of the four-pole core of the rotor.
    Type: Grant
    Filed: July 19, 1991
    Date of Patent: October 20, 1992
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Ikuo Matsushita
  • Patent number: 5140205
    Abstract: An electric motor incorporates a positive temperature coefficient resistor 18 between a supply terminal and a brush. The resistor can be inserted from outside the motor through an aperture 17 in an end cap 2. A body 19 of heat conducting material, also insertable from outside the end cap, can be provided and held against to resistor 18 to alter its effective thermal mass and so adjust its operating characteristics.
    Type: Grant
    Filed: January 7, 1991
    Date of Patent: August 18, 1992
    Assignee: Johnson Electric S.A.
    Inventor: Roger F. Baines
  • Patent number: 5105112
    Abstract: A blower for cooling an internal combustion engine of a power vehicle comprises an electric drive motor having a housing with slots for ventilation, and a series resistance provided on an outer side of the housing at a distance from the latter and covering the slots, the series resistance being connectable with and disconnectable from a working current circuit of the drive motor.
    Type: Grant
    Filed: July 6, 1990
    Date of Patent: April 14, 1992
    Assignee: Robert Bosch GmbH
    Inventors: Daniel Klumpp, Ernst Muenster, Wolfgang Scheidel, Ludger Adrian, Hartmut Nitzsche
  • Patent number: 5103125
    Abstract: An adapter for a mechanical throttle control to provide electrical signals to an electronic control for an engine. A mechanical vernier throttle control unit for converting rotational motion to linear motion is coupled directly to a potentiometer, the tap output of which is connected to the electronic control. Linear motion of the control unit is directly imparted to the potentiometer to provide engine speed signals to the engine through the electronic control module.
    Type: Grant
    Filed: July 28, 1989
    Date of Patent: April 7, 1992
    Inventor: Ronald H. Ogden
  • Patent number: 5102307
    Abstract: A motor-operated pump includes an electrical filter that includes an inductance and a capacitance mounted within the pump housing. The filter components are thereby shielded against possible damage during initial installation, or during shipment, or during maintenance operations. Electrically, the filter components are in direct connection with the motor terminals, so as to have maximum electrical effectiveness for suppression of radio frequency emissions that might otherwise be communicated to other on-board electrical components.
    Type: Grant
    Filed: September 4, 1990
    Date of Patent: April 7, 1992
    Assignee: Carter Automotive Company, Inc.
    Inventor: Paul M. Meyer
  • Patent number: 5093597
    Abstract: A saturable reactor diode snubber assembly is provided for use witha brushless excitation system. The diode snubber provided includes a thin film member composed of a saturable magnetic material. The magnetic material is saturated for a large percentage of the current cycle of each pase of the ac exciter. When the current approaches zero and the diode approaches reverse recovery, the magnetic film member of the present invention comes out of saturation and turns linear increasing overall exciter inductance and decreasing current fall rate, thereby reducing reverse recovery peak current and diode stored energy. This in turn reduces the effects of voltage spikes normally experienced during diode reverse recovery. The magnetic material is used at a predetermined thickness such that a desired result is obtainable. One embodiment of the invention involves placing the magnetic material on the side of the armature slot wedge adjacent to the top coil.
    Type: Grant
    Filed: October 1, 1990
    Date of Patent: March 3, 1992
    Assignee: Westinghouse Electric Corp.
    Inventor: Kevin B. Hughes
  • Patent number: 5010264
    Abstract: A miniature motor having a positive-coefficient thermistor in which a first supporting member made of an electrically conductive material and electrically connected to at least any one of a pair of brushes housed in a motor cover plate, and a second supporting member made of an electrically conductive material and electrically connected to an external terminal are provided; a positive-coefficient thermistor being supported between the first and second supporting members.This construction makes the assembly of the motor easy, leading to improved productivity, and allows the motor to have a positive overheat preventing function without adding to the number of parts.
    Type: Grant
    Filed: September 1, 1989
    Date of Patent: April 23, 1991
    Assignees: Mabuchi Motor Co., Ltd., Mitsui Mining & Smelting Co.
    Inventors: Shinjiro Yamada, Seiki Satoh, Kazuichi Mabuchi, Shiei Kitao, Yoshiaki Egawa
  • Patent number: 5003208
    Abstract: A miniature motor having a positive temperature coefficient thermistor comprising a stator having a permanent magnet serving as a field, a rotor formed by winding a plurality of rotor windings on a rotor core, brushes supported by a motor cover plate for feeding current to the rotor windings by making contact with a commutator, positive temperature coefficient thermistor for controlling current to the rotor windings, in which the positive temperature coefficient thermistor has one pole on one pole surface thereof, and a plurality of independent split poles corresponding to the rotor windings on the other pole surface thereof, and is fitted to an end face of the rotor core;the rotor windings being connected to the split poles of the positive-coefficient thermistor in such a manner as to be connected in series with the split poles of the positive-coefficient thermistor.
    Type: Grant
    Filed: August 4, 1989
    Date of Patent: March 26, 1991
    Assignee: Mabuchi Motor Co. Ltd.
    Inventors: Nobuhiro Hama, Tsutomu Saya, Sigeru Mitamura
  • Patent number: 4982130
    Abstract: An electric motor includes a stator and a rotor and a bearing that connects both in a rotatable manner. The rotor and stator include electric conductor paths leading to exciting coils and/or to electronic components, all arranged on an iron-plate serving as a magnetic return path. The iron-plate has at least one electrical insulating layer that serves to insulate it, as well as at least the conductive layer forming the conductor paths which are on the insulating layer.
    Type: Grant
    Filed: November 16, 1988
    Date of Patent: January 1, 1991
    Assignee: Papst-Motoren GmbH & Co. K.G.
    Inventors: Heinrich Cap, Edgar Zuckschwert
  • Patent number: 4959573
    Abstract: In an induction motor rotor windings are connected together in a squirrel cage or a wound rotor .DELTA. configuration and stator windings are connected in series across a source. A capacitor is connected in parallel with one of the stator windings and this combination is connected in series with the other stator winding and is sized to form a quasi-double-resonant circuit. Both a single-phase and a polyphase motor can be configured as a quasi-double-resonant circuit with respect to each input power phase. A switching circuit employing compactors allows changing the rotation direction of the motor in a polyphase motor. A further polyphase motor is also described with primary stator windings connected to each power phase input and interleaved secondary stator winding, magnetically coupled to the primary stator windings but not directly connected to the power inputs. The secondary stator windings have capacitors coupled in parallel thereto to form parallel floating resonant circuits.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: September 25, 1990
    Assignee: S.P.C. Holding, Co., Ltd.
    Inventor: Gary D. Roberts
  • Patent number: 4935653
    Abstract: A stator for a ceiling fan includes a disc with two different depth slots alternately formed on the outer peripheral edge. A primary winding and a secondary winding are respectively wound in the longer slots and the shorter slots. An axle is disposed through the center of the disc and a circuit board including one or more resistors is disposed on a surface of the disc. Two or more contacts are provided for connection to a switch for changing the power supplied to the windings through the contacts in order to change the rotational speed of the ceiling fan. A cavity is formed on the circuit board for receiving the resistors.
    Type: Grant
    Filed: May 12, 1989
    Date of Patent: June 19, 1990
    Inventor: Peter Cheng
  • Patent number: 4896067
    Abstract: A brush mounting plate for an electric motor is formed as a one piece element molded from a suitable electrically non conductive material. The plate is formed with various openings, recesses and lugs on its opposed faces which serve to mount and locate components such as brush holders, inductors, and thermo switches in a compact arrangement with various components assembled to opposite faces of the plate in a stacked relationship axially of the plate. The lugs are so arranged as to enable a snap fit assembly of the inductor and thermo switches on to the plate.
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: January 23, 1990
    Assignee: SWF Auto-Electric GmbH
    Inventor: Bernd Walther
  • Patent number: 4868906
    Abstract: When operating a synchronous machine as a synchronous generator, a suppression resistor is required across the main generator field. However when operating the synchronous machine as an induction motor, a current is induced in the main generator field which is typically greater than the current carrying capability of the suppression resistor.In order to overcome the foregoing problem, the present invention provides a centrifugally activated switch for mounting on a rotor and which provides an alternate current path for the induced current.
    Type: Grant
    Filed: November 10, 1987
    Date of Patent: September 19, 1989
    Assignee: Sundstrand Corporation
    Inventor: James D. Oilschlager, Jr.
  • Patent number: 4831295
    Abstract: An arrangement for reducing voltages appearing in turbosets, wherein in addition to a grounding brush (7) on the drive end (DE), another (18) grounding brush is provided on the nondrive end (NDE) and is connected to ground (5) by an RC element (19,20). In this way, when grounding brush (7) on the drive end malfunctions, static charges and alternating frequency currents are reliably discharged.The currents flowing on the nondrive end and the voltages appearing between grounding brush (18) and ground (5) further allow reliable statements to be made about the operational capability and operational safety of the shaft grounding.
    Type: Grant
    Filed: November 17, 1987
    Date of Patent: May 16, 1989
    Assignee: Asea Brown Boveri AG
    Inventor: Zlatimir Posedel
  • Patent number: 4772814
    Abstract: An improved electric motor is operated from a single phase alternating current power source and employs a start winding and a run winding connected in series. A capacitor is connected in parallel with the start winding; and the inductance of the start winding and the capacitance of the capacitor are selected to form an LC resonant circuit at the operating frequency, thereby displacing the phase of the alternating current in the motor winding by 90.degree..
    Type: Grant
    Filed: November 26, 1986
    Date of Patent: September 20, 1988
    Inventor: Alexander J. Lewus
  • Patent number: 4764698
    Abstract: A stator of an A.C. electric motor includes a magnetic core comprising a magnetic ring member and two "U"-shaped magnetic members connected to the ring member. The two "U"-shaped magnetic members hold the ring member therebetween and are angularly spaced from one another around the central axis of the ring member. A primary winding is wound on one of the two "U"-shaped members and a secondary winding is wound on the other "U"-shaped member. The secondary winding is short-circuited by a capacitor. When A.C. voltage is applied to the primary winding, A.C. voltage is induced on the secondary winding at a certain value, or more than the primary voltage. A rotary flux is formed in the ring member by magnetic fluxes induced by primary and secondary A.C. currents. Accordingly, a cage rotor or magnet rotor which is rotatably disposed in the ring member can be rotated.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: August 16, 1988
    Assignee: Tohoku Metal Industries, Ltd.
    Inventor: Koichi Murakami
  • Patent number: 4758753
    Abstract: A stator of an A.C. electric motor includes a magnetic core comprising a magnetic ring member and two "U"-shaped magnetic members connected to the ring member. The two "U"-shaped magnetic members hold the ring member therebetween and are angularly spaced from one another around the central axis of the ring member. A primary winding is wound on one of the two "U"-shaped member and a secondary winding is wound on the other "U"-shaped member. The secondary winding is short-circuited by a capacitor. When A.C. voltage is applied to the primary winding, A.C. voltage is induced on the secondary winding at a certain value or more of the primary voltage. A rotary flux is formed in the ring member by magnetic fluxes induced by primary and secondary A.C. currents. Accordingly, a cage rotor or magnet rotor which is rotatably disposed in the ring member can be rotated.
    Type: Grant
    Filed: January 26, 1983
    Date of Patent: July 19, 1988
    Assignee: Tohoku Meta Industries, Ltd.
    Inventor: Koichi Murakami
  • Patent number: 4750077
    Abstract: The distributed capacitance between coil turns in a coil device is increased, and a coil inductance and a low-pass filter are formed, whereby overvoltages and high frequency voltages are suppressed. The increased distributed capacitance is attained by inserting a ferroelectric insulator, such as a ceramic material, between the coil turns or by winding a metal foil-containing insulator film in the shape of a tape, round a coil conductor.
    Type: Grant
    Filed: January 6, 1986
    Date of Patent: June 7, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Nobutada Amagasa
  • 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: 4734603
    Abstract: To lessen mounting time and to optimize positioning of the Hall generator, the Hall generator and control electronics influenced by the generator so as to actuate a brushless dc motor are arranged on a common substrate and are provided with a common protective envelope whose dimensions are somewhat narrower than the cross-section of the motor slot. This substrate is inserted in the motor slot so that the Hall generator is located outside the slot and in the effective magnetic field of the motor's permanent magnet.
    Type: Grant
    Filed: June 4, 1986
    Date of Patent: March 29, 1988
    Assignee: Papst-Motoren GmbH & Co. KG
    Inventors: Johann von der Heide, Georg F. Papst, Rolf Mueller
  • Patent number: 4734607
    Abstract: A miniature motor having a plurality of commutator segments with commutator terminals which are connected to rotor windings. The commutator terminals are disposed on an insulating cylinder which is fixedly fitted to a motor rotating shaft, and a spark-quenching resistor connects each of the commutator segments. This resistor is a disc-shaped electrically conductive rubber ring which is fitted to the insulating cylinder so that the end face of the disc-shaped ring comes in contact with the commutator segment and commutator terminals and is brought into intimate contact with the commutator terminals by heating.
    Type: Grant
    Filed: November 10, 1986
    Date of Patent: March 29, 1988
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Masaaki Ikawa, Kazuichi Mabuchi
  • Patent number: 4728832
    Abstract: A bi-directional alternating current permanent magnet motor is disclosed that is operated with a rotational restraint that insures proper directional rotation of a load. The motor output shaft is loosly coupled to a pinion gear. In the event that the motor is unable to start in the correct direction, and inadvertently reverses itself, it is immediately unloaded. This unloading causes the motor to stop and start again in the correct direction with a momentum that typically is sufficient to run the motor and its gear train in the correct direction.
    Type: Grant
    Filed: August 7, 1986
    Date of Patent: March 1, 1988
    Assignee: Honeywell Inc.
    Inventors: Girts U. Jatnieks, Robert C. Knutson, Laurence C. Rodgers
  • Patent number: 4724347
    Abstract: A collectorless direct-current motor with a stator mounted on a motor flange and a rotor mounted so that it can rotate on a shaft, in which case power semiconductors for the purpose of commutating the currents of the stator are attached to parts of the motor for the purpose of dissipating the heat and a circuit board with electronic components is provided for the purpose of controlling the commutation, and the power semiconductors are electrically connected to the circuit board, in which case the power semiconductors (39) are attached to the motor flange (2), preferably the outside (29) thereof, in heat conducting contact.
    Type: Grant
    Filed: September 30, 1985
    Date of Patent: February 9, 1988
    Assignee: ebm Elektrobau Mulfingen GmbH & Co.
    Inventors: Wilhelm Reinhardt, Gunther Hofele