Patents Assigned to Mabuchi Motor Co. Ltd.
  • Patent number: 5972131
    Abstract: An Ag--Cu alloy for a sliding contact containing:a) 0.1 to 8.0 wt. % of Cu, based on the weight of the alloy, wherein at least 70 wt. % of the Cu contained in the alloy is solid-solubilized in an Ag-.alpha.-phase; andb) 0.1 to 4.0 wt. %, based on the weight of the alloy, of at least one metal selected from the group consisting of Ge, Ni, Sn, In, Zn, Mg, Mn, Sb, Pb and Bi.The Ag--Cu alloy is desirably utilized to form a composite with a Cu or Cu alloy base material. Such composite has been found to be very useful for fabricating the commutator of a compact DC motor.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: October 26, 1999
    Assignees: Tanaka Kikinzoku Kogyo K.K., Mabuchi Motor Co., Ltd.
    Inventors: Takao Asada, Keiji Nakamura, Isao Shibuya, Toshiya Yamamoto, Tetsuya Nakamura, Kiyoshi Nakama
  • Patent number: 5876862
    Abstract: Sliding contacts comprising alloys such as Pd/Cu/Ag, Pt/Cu/Ag, Pd/Cu/Ag/Ni, Pt/Cu/Ag/Ni, Ag/Pd/Cu,Au, Ag/Pt/Cu/Au and two-layered composites comprising a surface layer of one of the foregoing alloys and a base layer comprised of copper or a copper-containing alloy. Also, three-layered composites comprising a surface layer of one of the foregoing alloys, an intermediate layer of one of the foregoing alloys and a base layer comprised of copper or a copper-containing alloy as well as direct current motors comprising commutators comprising a three-layered composite.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: March 2, 1999
    Assignees: Mabuchi Motor Co., Ltd., Tanaka Kikinzoku Kogyo K.K.
    Inventors: Isao Shibuya, Toshiya Yamamoto, Takao Asada, Tetsuya Nakamura
  • Patent number: 5736799
    Abstract: A miniature motor having a rotor arranged within a casing within which a stator is mounted, and a rotary shaft of the rotor is supported by bearing units mounted on both ends of the casing. One of the bearing units is provided with a thrust receiving member for supporting an end portion of the rotary shaft in a thrust direction, and a bearing for supporting the rotary shaft in a radial direction within a rotary shaft insertion hole. The thrust receiving member having a dimension that is equal to or smaller than an inner diameter of a bottomed recess formed in the casing is laid on a flat bottom surface of the bottomed recess. The bearing is securely fixed within the bottomed recess and contacted against the thrust receiving member. The rotary shaft insertion hole is in fluid communication with a through-hole formed in a bottom plate of the bottomed recess.
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: April 7, 1998
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Junichi Harano, Shigeyoshi Iwamoto, Mitsuo Kase
  • Patent number: 5714810
    Abstract: A miniature motor comprising a housing formed into a bottomed hollow tubular shape and having a permanent magnet fixedly fitted to the inner circumferential surface thereof, a rotor facing the permanent magnet and comprising an armature iron core having a coil wound thereon and a commutator, an end plate fitted to an open end of the housing and having brushes coming in sliding contact with the commutator and input terminals electrically connected to the brushes, and a cooling fan provided between the armature iron core of the rotor and the commutator; the rotor being rotatably supported by bearings provided on the bottom of the housing and the end plate, in which an integral cooling fan is formed by providing a plurality of fins at circumferentially equal intervals between first and second fan rings fitted to the ends of the commutator and the armature iron core, respectively, and a plurality of bosses are provided on the end face of the second fan ring.
    Type: Grant
    Filed: May 28, 1996
    Date of Patent: February 3, 1998
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Toshiya Yuhi, Minako Sakamaki
  • Patent number: 5691863
    Abstract: A power feeding device for VTR rotating drums coaxially provided on an end face of a rotating drum, which has magnetic heads in the vicinity of the outer circumferential surface thereof and is rotatably provided coaxially with a stationary drum, adapted to feed power to electronic components incorporated in the rotating drum, in which slits are provided on the slip rings making sliding contact with power feeding brushes in parallel with the axial line of the slip rings. Two slip rings are fixedly fitted to a rotating shaft made of an electrically conductive material in the axial direction in a mutually insulated state, and power is fed to the electronic components from the slip ring on the side remoter from the rotating drum via the rotating shaft.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: November 25, 1997
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Toshiaki Takayanagi
  • Patent number: 5633542
    Abstract: A miniature motor comprising a case having a positive temperature coefficient resistor incorporated therein and a permanent magnet fixedly fitted thereto, a rotor comprising an armature and a commutator, and a case cap having a pair of power-feeding brushes and a pair of input terminals electrically connected to the brushes, in which a lanced and raised lug or lanced and raised projections are provided at the tip of a retaining member made of an electrically conductive material, a retaining part is formed by bending a part or the whole of the tip of the retaining member toward the side of the lanced and raised lug or lanced and raised projections, the size of a gap between a projection or a lanced and raised lug provided on any one surface of a pair of input terminals, and the retaining part in free state and the lanced and raised lug is made smaller than the thickness of the positive temperature coefficient resistor being inserted therebetween so that the positive temperature coefficient resistor can be inse
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: May 27, 1997
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Toshiya Yuhi, Takahiro Ohtake, Masahiko Kato, Ryouichi Someya
  • Patent number: 5598045
    Abstract: A miniature motor comprising a case having a permanent magnet fixedly fitted to the inner circumference thereof, a rotor having an armature iron core and a commutator, and a case cap having power-feeding brushes and input terminals in which a pair of connecting members made of an electrically conductive material are provided on the inner end face of the case cap in a state insulated from brush holders, and a pair of terminals is integrally provided on each of the connecting members and the brush holders; one terminal of the connecting member being connected to the input terminal directly or via other electrically conductive members, the other terminal of the connecting member being connected to a pig-tail wire, and a capacitor being connected across the terminals.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: January 28, 1997
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Takahiro Ohtake, Masahiko Kato, Toshiya Yuhi
  • Patent number: 5572077
    Abstract: A miniature motor including a case formed into a bottomed hollow tubular shape and having a permanent magnet on the inner circumferential surface thereof, a rotor consisting of an armature and a commutator, and a case cover fitted to an open end of the case, and having brushes making sliding contact with the commutator and input terminals electrically connected to the brushes, in which a ground terminal formed into a substantially W shape in planar projected profile, with a U-shaped engaging part provided at the central part thereof for engaging with the case cover, and pinching parts provided at both ends thereof, is interposed between a pair of the input terminals so that one pinching part of the ground terminal forces one of the input terminals in position, and the engaging part is interposed between the case and the case cover.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: November 5, 1996
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Hiroshi Kimura
  • Patent number: 5517067
    Abstract: A miniature D.C. motor has a casing in which magnets are disposed and a rotor is disposed inside the magnets. The rotating condition is detected by a rotation detector which comprises an inductor and a capacitor. The inductor detects leaking fluxes externally from the casing among fluxes created by mutual operations of the magnets and an armature and converts a change of the leaking fluxes into electric signals. The capacitor is electrically connected to the inductor so as to constitute a resonance circuit. The resonance circuit is mounted on an outer surface of the casing. A resonance frequency of the resonance circuit is made so as to correspond to a frequency to be generated for a rotating time of the armature.
    Type: Grant
    Filed: December 20, 1993
    Date of Patent: May 14, 1996
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Nobuyuki Sata
  • Patent number: 5502343
    Abstract: A miniature motor comprising a case made of a metallic material, formed into a bottomed hollow tubular shape and having a permanent magnet fixedly fitted to the inner circumferential surface thereof, a rotor having an armature facing the permanent magnet and a commutator, and a case cap fitted to an open end of the case, and having brushes for making sliding contact with the commutator and input terminals electrically connected to the brushes; the rotor being rotatably supported by bearings provided on the bottom of the case and the case cap, in which an internal space defined by the case and the case cap is filled with an atmosphere of a polymer having a weight-average molecular weight of 50-5000.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: March 26, 1996
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Kazutoshi Yoshimura, Kenji Hagiwara, Isao Shibuya
  • Patent number: 5500994
    Abstract: A miniature electric motor has a stator mounted within a casing and a rotor provided so as to face the stator. The rotor includes a rotary shaft rotatably supported to the casing, a rotor body into which the rotary shaft is inserted, the rotor body being made of plastic, and a magnetic layer formed on an outer circumferential surface of the rotary body and made of rare earth plastic magnetic material. Accordingly, it is possible to obtain a high torque even with a small amount of rare earth plastic magnet and to avoid separation or cracks of the magnetic layer.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: March 26, 1996
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Hideki Itaya
  • Patent number: 5473210
    Abstract: A stator for miniature motors having a permanent magnet fixedly fitted to the inner circumferential surface of a housing formed into a bottomed hollow cylindrical shape, in which the circumferential surface of the housing consists of two opposing flat parts and two concave cylindrical surfaces; engaging projections are provided on the flat parts, and flat surfaces coming in contact with said flat parts, and engaging surfaces facing coming in contact with the engaging projections are provided on the axial edge of the permanent magnet made of a flexible ferromagnetic material, and formed into an arc-segment shape in cross section; and the permanent magnet is fixedly fitted in the housing by bringing the arc-segment-shaped outer circumferential surfaces of the permanent magnet in contact with the cylindrical surfaces of the housing, and bringing the flat surfaces on the axial edges of the permanent magnet in contact with the flat parts by causing the engaging projections to cut into the engaging surfaces by the
    Type: Grant
    Filed: August 8, 1994
    Date of Patent: December 5, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Ryouichi Someya, Satoshi Suzuki, Hiroaki Takashima, Katsuyuki Ichikawa, Katsuhiko Katayama, Kunio Hiromasa, Kenichi Ebashi
  • Patent number: 5459365
    Abstract: A miniature motor including a case formed into a bottomed hollow tubular shape having a permanent magnet, an end cap fitted to an open end of the case, and a rotor having an armature iron core and a commutator. A sleeve made of a resin material and formed into a hollow cylindrical shape is fitted coaxially with the core constituting the armature iron core and the commutator, with a gap provided on at least one end face of the sleeve; a plurality of grooves facing at least an end face of the sleeve are provided on the iron core and the commutator at certain spacings in the circumferential direction; a projection for press-fitting to any one of the grooves is provided each on both end faces of the sleeve integrally with the sleeve; and a groove extending along the axial line of the sleeve is provided in the middle part of these projections.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: October 17, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Toshiya Yuhi
  • Patent number: 5446328
    Abstract: A miniature motor in which stators are mounted in an interior of a casing, and a preassembled commutator is provided on a rotor rotatably disposed to face the stators. The commutator has a sleeve body having a cylindrical portion provided with a flanged portion and a plurality of recesses, directed outwardly, in a side wall of the flanged portion, with the sleeve body being made of insulating material and mounted on a rotary shaft of the rotor. The commutator also has a plurality of conductive commutator pieces each having a body portion formed in an arcuate shape and mounted on an outer circumferential surface of the cylindrical portion, a terminal portion and at least one retainer portion, with each of the terminal portion and the retainer portion being received in the recesses.
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: August 29, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Satoshi Suzuki, Michio Tsunoda, Kunitaka Murai, Katsumi Yamada
  • Patent number: 5444314
    Abstract: A miniature motor comprising a case made of a metallic material, formed into a bottom hollow tubular shape and having a permanent magnet fixedly fitted to the inner circumferential surface thereof, a rotor consisting of an armature facing the permanent magnet and a commutator, and a case cover engaged with an open end of the case and comprising brushes making sliding contact with the commutator and input terminals electrically connected to the brushes; the rotor being rotatably supported by bearings provided on the bottom of the case and the case cover, and a printed circuit board having a control element and a soundproofing plate made of a soundproofing material being provided outside the case cover, in which the soundproofing plate is formed into a cross shape when projected on a plane orthogonally intersecting the axial line of the rotor.
    Type: Grant
    Filed: December 16, 1993
    Date of Patent: August 22, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventor: Kazuo Okada
  • Patent number: 5434460
    Abstract: A miniature motor including a case formed into a bottomed hollow tubular shape and having a permanent magnet fixedly fitted to the inner circumferential surface thereof, a rotor formed of an armature and a commutator, and a case cover engaged with an open end of the case and having brushes making sliding contact with the commutator and input terminals electrically connected to the brushes, in which each of brush arms is formed into an essentially U shape, with one free end thereof having a brush, and the other free end thereof being fitted to the case cover in the vicinity of internal terminals. Each of the internal terminals has an essentially V-shaped connecting part for making contact with the brush arm and is fitted to the case cover in elastically deformed state.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: July 18, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Kazuichi Mabuchi, Makoto Sato
  • Patent number: 5412271
    Abstract: Disclosed is a small-sized electric motor equipped with an improved electric connector, which prevents high forces being exerted on exposed conductors of an insulated wire in the course of insertion or withdrawal of the exposed conductors from the connector housing, thereby preventing the rubbing between the exposed conductors and the terminal contacts of the electric connector.The electric connector includes an actuator. The actuator, when fully inserted in said connector housing, is adapted to push the exposed conductors against the contacts of the contact beams of the terminals, thereby causing the contact beams of the terminals to be forced into the exposed conductors.
    Type: Grant
    Filed: August 9, 1994
    Date of Patent: May 2, 1995
    Assignees: Molex Incorporated, Mabuchi Motor Co., Ltd.
    Inventors: Yoshiyuki Mizuno, Hidehiro Ii, Satoshi Suzuki, Yukihisa Tonooka
  • Patent number: 5412266
    Abstract: A miniature motor comprising a rotor having a plurality of magnetic poles extending axially, which is disposed radially on the outer circumferential surface of the rotor, and a stator having two coils wound on coil bobbins, which are disposed axially in a housing formed into a bottomed hollow cylindrical shape; an end plate being fitted to an open end of the housing, in which the housing is made of a ferromagnetic material, the magnetic poles are provided on a housing-side end face of the rotor so that an axial magnetic attraction force is exerted between the rotor end face and the housing.
    Type: Grant
    Filed: April 21, 1993
    Date of Patent: May 2, 1995
    Assignee: Mabuchi Motor Co. Ltd.
    Inventors: Akira Okazaki, Shinichi Matsuda, Takanobu Lee, Ikuo Matsushita, Masao Take
  • Patent number: 5412267
    Abstract: A miniature motor including a motor case formed into a bottomed hollow cylindrical shape having a cross-sectional shape having two long sides consisting of two parallel lines (planar portions) and two short sides. An end bracket is fitted to an open end of the motor case. Permanent magnets are fixedly fitted to the cylindrical inside surface of the motor case. The inside surfaces of the permanent magnets, when assembled, form part of a cylindrical surface. An armature is rotatably supported in the motor case via bearings provided on the motor case and the end bracket. Recesses are provided on the inside of the parallel planar portions of the motor case and positioned in such a manner that a gap g.sub.1 between the inside surfaces of the recesses and the armature is related to a gap g.sub.2 between the inside surfaces of the permanent magnets and the armature by a relationship that g.sub.1 g.sub.2. A method is further proposed of making the motor in which the recesses are formed by ironing.
    Type: Grant
    Filed: May 14, 1993
    Date of Patent: May 2, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Kazuo Okada, Keisuke Ebihara, Kazumasa Saiga
  • Patent number: 5405199
    Abstract: A bearing device for miniature motors comprising a stator formed by fitting an end plate to an open end of a housing formed into a bottomed hollow cylindrical shape. A rotor rotatably supported by bearings is provided on the housing and the end plate. A bearing retaining body is provided formed of a resin material into a basket shape. The bearing retaining body has such a construction that a flange and a bottom member, both formed into a ring shape, are connected by a plurality of axially extending and circumferentially disposed connecting members. A plurality of axially extending support columns are disposed in the circumferential direction on the inner edge surface of the bottom member. The bearing retaining body is fitted to a retaining part provided on the housing and/or the end plate, and a ball bearing is supported via the supporting claims.
    Type: Grant
    Filed: December 1, 1992
    Date of Patent: April 11, 1995
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Kazuichi Mabuchi, Yoshiaki Egawa, Makoto Satou