Patents by Inventor Sakae Fujitani

Sakae Fujitani 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: 9787234
    Abstract: A drive controller of an instrument controls a stepping motor to rotate a pointer of the instrument attached to a rotation shaft of the stepping motor, the pointer rotatable between a zero scale position and a maximum scale position. The drive controller controls the stepping motor to perform a sweeping operation in which the pointer is swung from the zero scale position to the maximum scale position and returned back to the zero scale position, wherein the drive controller controls the stepping motor, during the sweeping operation, to accelerate to a predetermined speed by outputting a rated torque signal to the stepping motor and controls the stepping motor to rotate at the predetermined speed by outputting a decreased torque signal to the stepping motor, the decreased torque signal being lower than the rated torque signal.
    Type: Grant
    Filed: April 7, 2016
    Date of Patent: October 10, 2017
    Assignee: Minebea Co., Ltd.
    Inventors: Sakae Fujitani, Nobuyuki Sueyoshi
  • Publication number: 20160301343
    Abstract: A drive controller of an instrument controls a stepping motor to rotate a pointer of the instrument attached to a rotation shaft of the stepping motor, the pointer rotatable between a zero scale position and a maximum scale position. The drive controller controls the stepping motor to perform a sweeping operation in which the pointer is swung from the zero scale position to the maximum scale position and returned back to the zero scale position, wherein the drive controller controls the stepping motor, during the sweeping operation, to accelerate to a predetermined speed by outputting a rated torque signal to the stepping motor and controls the stepping motor to rotate at the predetermined speed by outputting a decreased torque signal to the stepping motor, the decreased torque signal being lower than the rated torque signal.
    Type: Application
    Filed: April 7, 2016
    Publication date: October 13, 2016
    Inventors: Sakae FUJITANI, Nobuyuki SUEYOSHI
  • Patent number: 7145423
    Abstract: An electromagnetic actuator with high performance such as high speed and high resolution is inexpensively provided with solutions to problems associated with power supply and leakage flux, which have been involved in the structure of a moving coil type and have been shortcomings of a VCM type actuator. A composite electromagnetic actuator apparatus employs the foregoing electromagnetic actuator. The electromagnetic actuator is equipped with a stationary assembly that includes two coils disposed coaxially with each other inside a hollow stator yoke composed of a soft magnetic material, and a movable assembly composed of a movable magnet unit and a movable yoke unit both disposed inside the coils with a very small clearance therefrom so as to be movable in the axial direction, wherein the movable assembly travels in the axial direction by the interaction between a magnetic field generated by the movable magnet unit and a current passing through the coils.
    Type: Grant
    Filed: August 25, 2005
    Date of Patent: December 5, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Patent number: 7049723
    Abstract: The disclosure describes a DC motor including a rotor unit arranged within the motor body and has a cylindrical field magnet fixed to an outer surface of a holder. The holder has a rotating shaft press-fitted through the center, and the cylindrical field magnet has the S and the N poles alternately around a circumference. There is a stator unit which is circumferentially arranged around the rotor unit, that is made of a plurality of stator yokes that are arranged so that they oppose the field magnet through a small gap. Each of the stator yokes is formed by circumferentially stacking a large number of thin plates, each consisting of a salient pole, and a number of coil units, each formed by winding a magnet wire on a bobbin, and mounting the bobbins on the stator yokes. In the described arrangement, each of the S and N poles has a plurality of stages formed in an axial direction and shifted from each other in the circumferential direction by a predetermined shift amount with respect to the field magnet.
    Type: Grant
    Filed: January 14, 2002
    Date of Patent: May 23, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Seiichi Matsuura
  • Publication number: 20060044096
    Abstract: An electromagnetic actuator with high performance such as high speed and high resolution is inexpensively provided with solutions to problems associated with power supply and leakage flux, which have been involved in the structure of a moving coil type and have been shortcomings of a VCM type actuator. A composite electromagnetic actuator apparatus employs the foregoing electromagnetic actuator. The electromagnetic actuator is equipped with a stationary assembly that includes two coils disposed coaxially with each other inside a hollow stator yoke composed of a soft magnetic material, and a movable assembly composed of a movable magnet unit and a movable yoke unit both disposed inside the coils with a very small clearance therefrom so as to be movable in the axial direction, wherein the movable assembly travels in the axial direction by the interaction between a magnetic field generated by the movable magnet unit and a current passing through the coils.
    Type: Application
    Filed: August 25, 2005
    Publication date: March 2, 2006
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Patent number: 6960847
    Abstract: An electromagnetic actuator with high performance such as high speed and high resolution is inexpensively provided with solutions to problems associated with power supply and leakage flux, which have been involved in the structure of a moving coil type and have been shortcomings of a VCM type actuator. A composite electromagnetic actuator apparatus employs the foregoing electromagnetic actuator. The electromagnetic actuator is equipped with a stationary assembly that includes two coils disposed coaxially with each other inside a hollow stator yoke composed of a soft magnetic material, and a movable assembly composed of a movable magnet unit and a movable yoke unit both disposed inside the coils with a very small clearance therefrom so as to be movable in the axial direction, wherein the movable assembly travels in the axial direction by the interaction between a magnetic field generated by the movable magnet unit and a current passing through the coils.
    Type: Grant
    Filed: May 22, 2001
    Date of Patent: November 1, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Patent number: 6882073
    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: Grant
    Filed: October 8, 2004
    Date of Patent: April 19, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Publication number: 20050046291
    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 movble 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 8, 2004
    Publication date: March 3, 2005
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Patent number: 6856065
    Abstract: An electric rotary machine includes a stator comprising: a stator ring; a plurality of discrete salient poles each comprising a bobbin with guide grooves and a pole tooth with a groove, disposed inside the stator ring, and fixed by a molding resin injected inside the stator ring; and a positioning ring having protrusions at its outer circumference and engaging with the discrete salient poles such that the protrusions are each fitted into the groove of the pole tooth.
    Type: Grant
    Filed: February 20, 2003
    Date of Patent: February 15, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Seiichi Matsuura, Sakae Fujitani, Kazuo Muramatsu
  • Patent number: 6815861
    Abstract: An electric rotary machine comprises: a cylindrical pole tooth ring provided with a plurality of slits; and a plurality of salient poles each including a pole tooth. The salient poles are each positioned and fixed such that the pole tooth is fitted into the slit, which, by means of openings formed on the pole tooth ring along and close to the side wall of the slit, is adapted to be elastically deformed when receiving the pole tooth fitted thereinto.
    Type: Grant
    Filed: January 28, 2003
    Date of Patent: November 9, 2004
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Seiichi Matsuura, Sakae Fujitani
  • Patent number: 6809438
    Abstract: The stator assembly of a PM stepping motor having a two-phase structure in which two stators arranged along the circumferential direction in such a manner that respective pole teeth are intermeshed together are combined back to back so as to phase-shift the respective pole teeth in the two stators at an electrical angle of 90°. The field rotor magnet is so arranged as to face the respective pole teeth at a small distance, and is magnetized on its circumferential surface along the circumferential direction with a plurality of alternating N- and S-poles having a preset width not matching the pole tooth pitch of each stator.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: October 26, 2004
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Taketoshi Ohyashiki, Sakae Fujitani
  • Patent number: 6765320
    Abstract: The present invention provides a rotor magnet with a claw pole type of actuator of a single phase structure and a magnetization method of the rotor magnet, in which detent and dynamic torques are sufficiently ensured, an angle range of rotational operation is wide, the cost is inexpensive and the characteristics are stable. In the actuator of such structure, the rotor magnet is rotatably arranged through a fine space inside an armature coil, wherein the rotor magnet comprises a single cylindrical type of magnet having a distribution pattern of a magnetic flux in which the magnetic pole peak position of at least one of the N and S poles is shifted stepwise in the axial direction thereof.
    Type: Grant
    Filed: April 3, 2000
    Date of Patent: July 20, 2004
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Masaki Kagawa
  • Patent number: 6756871
    Abstract: An inexpensive, small, high-efficiency actuator having a single-phase claw pole structure permits easy assembly or winding and enables a rotor to act in a fixed direction by detent torque even in a deenergization mode.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: June 29, 2004
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Masaki Kagawa
  • Patent number: 6717319
    Abstract: An electric rotary machine comprises a cylindrical pole tooth ring and a plurality of salient poles each including a pole tooth. The salient poles are each positioned and fixed such the pole tooth makes firm contact with the pole tooth ring by means of each of a plurality of mechanisms, which are arrayed circumferentially on the pole tooth ring, and which each comprise bend-ups adapted to be elastically deformed when the pole tooth is fitted into the mechanism.
    Type: Grant
    Filed: January 28, 2003
    Date of Patent: April 6, 2004
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Seiichi Matsuura, Kunitake Matsushita, Masato Hata, Sakae Fujitani
  • Publication number: 20030205941
    Abstract: An electromagnetic actuator with high performance such as high speed and high resolution is inexpensively provided with solutions to problems associated with power supply and leakage flux, which have been involved in the structure of a moving coil type and have been shortcomings of a VCM type actuator. A composite electromagnetic actuator apparatus employs the foregoing electromagnetic actuator. The electromagnetic actuator is equipped with a stationary assembly that includes two coils disposed coaxially with each other inside a hollow stator yoke composed of a soft magnetic material, and a movable assembly composed of a movable magnet unit and a movable yoke unit both disposed inside the coils with a very small clearance therefrom so as to be movable in the axial direction, wherein the movable assembly travels in the axial direction by the interaction between a magnetic field generated by the movable magnet unit and a current passing through the coils.
    Type: Application
    Filed: May 22, 2001
    Publication date: November 6, 2003
    Applicant: MINEBEA CO., LTD.
    Inventors: Yuzuru Suzuki, Sakae Fujitani, Naoyuki Harada, Kunitake Matsushita
  • Publication number: 20030160533
    Abstract: An electric rotary machine includes a stator comprising: a stator ring; a plurality of discrete salient poles each comprising a bobbin with guide grooves and a pole tooth with a groove, disposed inside the stator ring, and fixed by a molding resin injected inside the stator ring; and a positioning ring having protrusions at its outer circumference and engaging with the discrete salient poles such that the protrusions are each fitted into the groove of the pole tooth.
    Type: Application
    Filed: February 20, 2003
    Publication date: August 28, 2003
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Seiichi Matsuura, Sakae Fujitani, Kazuo Muramatsu
  • Publication number: 20030141780
    Abstract: An electric rotary machine comprises a cylindrical pole tooth ring and a plurality of salient poles each including a pole tooth. The salient poles are each positioned and fixed such the pole tooth makes firm contact with the pole tooth ring by means of each of a plurality of mechanisms, which are arrayed circumferentially on the pole tooth ring, and which each comprise bend-ups adapted to be elastically deformed when the pole tooth is fitted into the mechanism.
    Type: Application
    Filed: January 28, 2003
    Publication date: July 31, 2003
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Seiichi Matsuura, Kunitake Matsushita, Masato Hata, Sakae Fujitani
  • Publication number: 20030141781
    Abstract: An electric rotary machine comprises: a cylindrical pole tooth ring provided with a plurality of slits; and a plurality of salient poles each including a pole tooth. The salient poles are each positioned and fixed such that the pole tooth is fitted into the slit, which, by means of openings formed on the pole tooth ring along and close to the side wall of the slit, is adapted to be elastically deformed when receiving the pole tooth fitted thereinto.
    Type: Application
    Filed: January 28, 2003
    Publication date: July 31, 2003
    Applicant: Minebea Co. , Ltd.
    Inventors: Yuzuru Suzuki, Seiichi Matsuura, Sakae Fujitani
  • Publication number: 20020180282
    Abstract: The stator assembly of a PM stepping motor having a two-phase structure in which two stators arranged along the circumferential direction in such a manner that respective pole teeth are intermeshed together are combined back to back so as to phase-shift the respective pole teeth in the two stators at an electrical angle of 90°. The field rotor magnet is so arranged as to face the respective pole teeth at a small distance, and is magnetized on its circumferential surface along the circumferential direction with a plurality of alternating N- and S-poles having a preset width not matching the pole tooth pitch of each stator.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 5, 2002
    Applicant: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Taketoshi Ohyashiki, Sakae Fujitani
  • Patent number: 6455962
    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: Grant
    Filed: March 13, 2001
    Date of Patent: September 24, 2002
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Kunitake Matsushita, Hiroichi Shibata, Naoyuki Harada, Taketoshi Ohyashiki, Sakae Fujitani, Hirohito Nakamata