Patents by Inventor Yuzuru Suzuki

Yuzuru Suzuki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6411006
    Abstract: Electromagnetic conversion efficiency of an electric rotary machine is enhanced and reduction of leakage flux due to magnetic discontinuity can be realized without providing holes for positioning and fixing salient poles in a stator ring. Outer appearance and decency of the electric rotary machine as a product are also improved by not allowing lower ends of salient poles of an armature assembly to be exposed on an outer surface of the electric rotary machine. For this purpose a radial gap type electric rotary machine comprises a field magnetic pole consisting of a permanent magnet which is supported rotatably and an armature assembly consisting of a plurality of divided salient poles which oppose the field magnetic pole with a small air gap therebetween and are radially arranged with respect to a rotation axis. The armature assembly includes a first ring made of a soft magnetic member for receiving the plurality of salient poles and a second ring made of a soft magnet member for receiving the first ring.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: June 25, 2002
    Assignee: Minebera Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Taketoshi Ohyashiki, Naoyuki Harada
  • Publication number: 20020068658
    Abstract: A planetary gear reduction device with a torque limiter function includes a housing, an input shaft rotatably supported by one end of the housing and connected to a power source so as to input a torque from the power source, an output shaft rotatably supported by the other end of the housing so as to output the torque from the power source, a reduction gear train provided between the input shaft and the output shaft and constituted of a plurality of gears meshing with one another, and a torque limiting mechanism mounted in the reduction gear train. In this device, when an excessive torque is generated in the output shaft, torque transmission from the input shaft to the output shaft is disconnected by the action of the torque limiting mechanism.
    Type: Application
    Filed: November 29, 2001
    Publication date: June 6, 2002
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Kunitake Matsushita, Kazuo Muramatsu
  • Publication number: 20020050747
    Abstract: There is provided a stepping motor of low vibration realized by reducing cogging with a simple structure while maintaining the performances such as torque.
    Type: Application
    Filed: October 25, 2001
    Publication date: May 2, 2002
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Taketoshi Ohyashiki, Kunitake Matsushita
  • Publication number: 20020043880
    Abstract: In order to reduce cost through reduction in material cost and improvement of productivity, in a linear type actuator comprising: a stator unit having coils consisting of wound magnet wires and housed inside stator sub-assemblies and pole teeth arranged on the inner circumference thereof; a rotor unit having a field magnet arranged on the outer circumference thereof and rotatably disposed so as to oppose the pole teeth with a given gap; an output shaft attached to a center portion of the rotor unit and movable in the axial direction thereof; and converting means provided on the innermost diametral circumferential surface of the rotor unit and adapted to convert rotary motion of the rotor unit into linear motion of the output shaft, the converting means is made of a material different from that of the rotor unit.
    Type: Application
    Filed: October 10, 2001
    Publication date: April 18, 2002
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Patent number: 6346759
    Abstract: The present invention provides, at low cost, a stator structure of a high-performance motor, which gives off lower temperature rise, strives for a more highly efficient magnetic circuit, and achieves lower power consumption at highspeed rotation, while at the same time striving to achieve a stable rotor position by preventing rotor float at highspeed rotation. In a highspeed motor comprising a stator including a stator yoke made of a soft magnetic material and coils composed of magnet wires wound on salient poles of the stator yoke; A rotor including a field magnet includes a permanent magnet so as to face the salient poles of the stator by way of an air gap and a shaft as the center of rotation in the center thereof; and a base plate having a housing which has two bearings for rotatably holding the rotor in the center of the stator, improvement being that the stator yoke is constituted by winding a soft magnetic steel sheet.
    Type: Grant
    Filed: January 26, 2000
    Date of Patent: February 12, 2002
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Taketoshi Ohyashiki, Naoyuki Harada
  • Patent number: 6331746
    Abstract: The present invention provides, in a single phase-structure actuator, a rotor magnet structure having characteristics wherein detent torque is fully assured, and there is also a large rotation angle range.
    Type: Grant
    Filed: January 25, 2000
    Date of Patent: December 18, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Sakae Fujitani, Yuzuru Suzuki, Masaki Kagawa
  • Patent number: 6320288
    Abstract: An optimum arrangement of position detectors which is inexpensive but hardly affected by intrinsic mechanical deflection or radial displacement on a rotary structure or motor and by a secondary artifact or variation i the magnetic coupling resulting from the mechanical deflection or radial displacement. A brushless DC motor with N phases (N≧2) according to the present invention is provided having position detectors of which signal outputs are indicative of the location of magnetic poles of a rotor and used for controlling the rotation for a constant speed. More particularly, it includes any two adjacent position detectors being spaced from each other by a spatial angle &thgr;i (rad) about the center of the rotor, (1/n)*(&thgr;i/2&pgr;)<KM is established where i=1 to N−1, 0<&thgr;i<2&pgr;/N, KM is the mechanical time constant of the motor (sec), and n is the number of revolutions (rps).
    Type: Grant
    Filed: February 29, 1996
    Date of Patent: November 20, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Taketoshi Ohyashiki, Kenichi Makino
  • Patent number: 6299129
    Abstract: In a device wherein a rotary shaft is provided in a pipe through which a fluid is passed, a butterfly valve is installed in the pipe, an actuator and an angle sensor are directly arranged on the outer end of the pipe of the rotary shaft, and angle control for adjusting an angle detection signal to a command value is performed to thereby adjust an amount of a fluid passing through the pipe. An actuator includes a rotor composed of a permanent magnet rotatably supported by the rotary shaft and has two magnetic poles, namely, N and S poles, and a stator composed of a winding wrapped around a cylindrical core formed of a soft magnetic member.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: October 9, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada
  • Publication number: 20010026103
    Abstract: A terminal of a motor is provided, in which a connection between a coil and an external circuit can be carried out securely and with a good workability, while saving material resources and enhancing safety relating to environmental pollution. A terminal (23) consists integrally of a magnet wire binding section (20) to connect to a magnet wire (4) of a coil (6), an external connection section (21) to connect to an external circuit and a support base section (22) to press-fit into a terminal block (19) of a bobbin (5) and hold the terminal (23), and the magnet wire (4) is plasma welded for connection through to the external connection section (21) (terminal 23). The connection of the terminal is carried out by welding (plasma welding), thus the end of the magnet wire of a motor (1) is connected without using solder containing lead. As a result, since lead is not used, material resources can be saved and safety relating to the environmental pollution can be enhanced.
    Type: Application
    Filed: March 13, 2001
    Publication date: October 4, 2001
    Applicant: MINEBEA CO., LTD.
    Inventors: Yuzuru Suzuki, Kunitake Matsushita, Hiroichi Shibata, Naoyuki Harada, Taketoshi Ohyashiki, Sakae Fujitani, Hirohito Nakamata
  • Publication number: 20010022479
    Abstract: To provide a toroidal core type actuator having a stator unit which is increased in winding density, is improved in methods of the terminal handling after winding, the positioning of the stator after winding, and the fixing of the same, and is excellent in working properties. A toroidal core type actuator having a stator and a rotor is provided, the stator having winding applied to a hollow cylindrical core composed of soft magnetic material, the rotor including a permanent magnet having north poles and south poles alternately arranged in total of m along the circumferential direction thereof, the rotor being rotatably arranged in the core of the stator via a minute air gap, wherein m of phase separators composed of non-magnetic material are arranged on the peripheral surface of the hollow cylindrical core so as to be separated from each other by 360°/m and the winding is applied to winding regions separated from each other by the phase separators.
    Type: Application
    Filed: May 21, 2001
    Publication date: September 20, 2001
    Applicant: Minebea Co. Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Takashi Ishii, Naoyuki Harada
  • Patent number: 6288507
    Abstract: A motor drive circuit is comprised of an H-bridge circuit which is formed of a flywheel diode and a switching device and connected to a motor coil; a current detecting circuit which is connected to the H-bridge circuit, has a plurality of shunt resistors, and computes a motor coil current value on the basis of voltage drops in the shunt resistors; a memory for storing an energizing direction of the motor coil and command value data regarding an energizing current waveform; a control circuit issues energizing current amount of the motor coil so that an error between command value data stored in the memory and a detected current signal detected by the current detecting circuit always stays zero; and a switching device driving logic circuit switches both source and sink of the H-bridge circuit when the motor coil is excited.
    Type: Grant
    Filed: October 20, 1999
    Date of Patent: September 11, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Kenichi Makino, Yuzuru Suzuki, Sakae Fujitani
  • Publication number: 20010017501
    Abstract: Electromagnetic conversion efficiency of an electric rotary machine is enhanced and reduction of leakage flux due to magnetic discontinuity can be realized without providing holes for positioning and fixing salient poles in a stator ring. Outer appearance and decency of the electric rotary machine as a product are also improved by not allowing lower ends of salient poles of an armature assembly to be exposed on an outer surface of the electric rotary machine. For this purpose a radial gap type electric rotary machine comprises a field magnetic pole consisting of a permanent magnet which is supported rotatably and an armature assembly consisting of a plurality of divided salient poles which oppose the field magnetic pole with a small air gap therebetween and are radially arranged with respect to a rotation axis. The armature assembly includes a first ring made of a soft magnetic member for receiving the plurality of salient poles and a second ring made of a soft magnet member for receiving the first ring.
    Type: Application
    Filed: February 23, 2001
    Publication date: August 30, 2001
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakea Fujitani, Taketoshi Ohyashiki, Naoyuki Harada
  • Patent number: 6236135
    Abstract: To provide a toroidal core type actuator having a stator unit which is increased in winding density, is improved in methods of the terminal handling after winding, the positioning of the stator after winding, and the fixing of the same, and is excellent in working properties. A toroidal core type actuator having a stator and a rotor is provided, the stator having winding applied to a hollow cylindrical core composed of soft magnetic material, the rotor including a permanent magnet having north poles and south poles alternately arranged in total of m along the circumferential direction thereof, the rotor being rotatably arranged in the core of the stator via a minute air gap, wherein m of phase separators composed of non-magnetic material are arranged on the peripheral surface of the hollow cylindrical core so as to be separated from each other by 360°/m and the winding is applied to winding regions separated from each other by the phase separators.
    Type: Grant
    Filed: December 9, 1999
    Date of Patent: May 22, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Takashi Ishii, Naoyuki Harada
  • Patent number: 6201324
    Abstract: A stator structure enables a claw pole motor to be reduced in diameter and to highly increase its performance.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: March 13, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Masaki Kagawa
  • Patent number: 6194806
    Abstract: An iron core type cylindrical radial gap type motor structure, by having field magnetic poles generated by permanent magnets and, in opposition to these, salient poles generating a rotational magnetic field and arranged with their emission direction along the rotational axis, the shape of salient poles being approximately T-shaped in cross-section along the rotational axis direction, and I-shaped in cross-section at right angles to the rotational axis direction, the upper end of said T-shaped opposing the axial direction of the rotor magnets and the lower end being mechanically coupled and fixed to the stator ring, thus constructing the magnetic circuit of the armature, and where the relationship between the length L1 of the said salient pole in the axial direction opposed to the field magnetic pole, and the length L2 in the axial direction of the coil core section about which the coil is wrapped, satisfies the conditions 0.3*L1≦L2≦0.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: February 27, 2001
    Assignee: Minebea Co., Limited
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Yoshiyuki Aono, Masaki Kagawa
  • Patent number: 6177751
    Abstract: The object of the present invention is to provide a rotary electric machine that provides bobbins with good assembling efficiency and allows no dislocation of the stator. A motor 2 comprises a case 4, a stator 6 secured inside the case 4, a rotor 10 formed into one piece with a rotating shaft 8. The stator 6 comprises stator yokes 32 and the stator yokes are secured in a radial manner in the case 4. Furthermore, resin 58 is filled in between the stator 6 and the case 4 with a space for the rotor being left. The stator yokes 32 comprise a salient pole 34, a bobbin 36 for holding the salient pole 34, and a magnetic wire 38 wound around the bobbin 36. A collar 39b of the bobbin 36 is formed so as to contact each other with notches 3 formed on two, upper and lower edge portions. Accordingly, combining two bobbins 36, 36 allows through-holes 5 penetrating the collar 39b thereof.
    Type: Grant
    Filed: August 20, 1999
    Date of Patent: January 23, 2001
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Kunitake Matsushita, Takayuki Yamawaki, Hiroshi Sano, Kazuo Muramatsu, Taichi Nishio
  • Patent number: 6166468
    Abstract: The object of the present invention is to provide a rotary electric machine which has high assembly accuracy, high heat dissipating efficiency, and excellent durability at the bearing portion. A motor comprises a case, a stator secured within the case, and a rotor formed into one piece with a rotary shaft. The case is provided, on both end faces, with flanges, and one of the flanges is provided with a ball bearing. A stator is radially secured within the case, resin is filled in between the stator and the case with a space of the rotor being left, and a bearing housing and a boss are formed on one side. An open portion is formed in between ribs of the bearing housing, and inserting the bearing into the bearing housing causes a part of the bearing to be exposed through the open portion to fixedly contact with the flange. This allows supporting the bearing securely, and allows frictional heat generated, and the like, to dissipate to the outside via the flange.
    Type: Grant
    Filed: August 3, 1999
    Date of Patent: December 26, 2000
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Kunitake Matsushita, Takayuki Yamawaki, Hiroshi Sano, Kazuo Muramatsu, Taichi Nishio
  • Patent number: 6157112
    Abstract: A brushless DC motor, having a rotor with a cylindrical rotor magnet supported rotationally by a shaft held by bearings mounted on a substantially planar base plate, and a stator supported by the base plate, and including a plurality of radially spaced salient poles holding stator coils formed by windings of magnet wire. Opposing surfaces of the rotor and each salient pole are defined by a first surface of a magnetic core of the salient pole, which is received in a bobbin, and a second surface of the magnetic core orthogonal to the first surface, and the rotor magnet has permanent magnet poles forming a first surface opposing the first surface of the magnetic core, and a second surface opposing the second surface of the magnetic core. A tip of each magnetic core is received through a hole formed in the base plate.
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: December 5, 2000
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Taketoshi Ohyashiki, Naoyuki Harada, Taichi Nishio
  • Patent number: 6140726
    Abstract: A radial gap type cylindrical motor structure including a rotor which has a field magnet 13, a stator poles 20 having salient poles 18 opposed to the field magnet 13 of the rotor, a magnetic flux density adjusting yoke 21 formed in a cylindrical shape using a soft magnetic material and having salient poles 18, half the number of salient poles being projected as upper salient poles on an inner upper edge of the yoke inwardly at an equal angle and the remaining half of the salient poles being projected as lower salient poles on an inner lower edge of the yoke inwardly at an equal angle so as not to overlap the upper salient poles vertically, and driving coils 12 wound respectively around the upper and lower salient poles.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: October 31, 2000
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Masaki Kagawa
  • Patent number: 6133660
    Abstract: A brushless DC motor including a rotor, a field magnet, and fixed poles having salient poles opposed to the field magnet. A bearing structure includes a rotating portion adapted to rotate with the rotor, a part of which rotating portion contacts the shaft, and a groove formed in the rotating contact portion at a predetermined angle between an angle parallel to the axial direction of the rotating portion and an angle perpendicular thereto. A lubricating oil fills both the rotating contact portion and the groove. A plastic plate is disposed under the rotating portion to bear a thrust force of the rotating portion.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: October 17, 2000
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Taketoshi Ohyashiki, Naoyuki Harada