Patents by Inventor Kunitake Matsushita

Kunitake Matsushita 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: 7193340
    Abstract: A low-profile stepping motor is disclosed, which is preferably used in downsized and lower-profiled electronic devices, such as a printer, a facsimile, a floppy disk drive, and the like. The motor comprises a stator assembly composed of first and second stator units (A, B) , and a rotor assembly (50) rotatably disposes inside the stator assembly. The stator units (A, B) are shaped and structured identically with each other, and each structured such that upper and lower stator yokes (30/32, 31/33) , which each have a plurality of pole teeth formed along one side, and which each have an exciting coil (40/42) disposed toward one side opposite to the one side having the pole teeth, are coupled to each other with their respective pole teeth intermeshing with each other with a shift of 180 degree electrical angle.
    Type: Grant
    Filed: February 12, 2003
    Date of Patent: March 20, 2007
    Assignee: Minebea Co., Ltd.
    Inventor: Kunitake Matsushita
  • 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: 7140758
    Abstract: A mechanism for deflecting a headlamp optical axis comprises a connecting lever, a bracket, a stepping motor, a front end plate, and a traveling block. The bracket is attached to an outside frame constituting an automotive vehicle body, and the stepping motor is attached to the bracket in a horizontally movable manner. The stepping motor has a rotary shaft which has a screw formed thereon and engaging threadedly with the traveling block. The connecting lever is attached to the outside frame in a horizontally movable manner. In the mechanism structured above, when the rotary shaft rotates, the traveling block is caused to travel along the rotary shaft thereby causing the both ends of the connecting lever to move in respective arc paths, whereby an optical axis of a headlamp attached to one of the both ends of the connecting lever is deflected.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: November 28, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Kunitake Matsushita, Sylvie Belavsky
  • Publication number: 20060238050
    Abstract: There is provided a stepping motor including: a stator assembly; a rotary shaft which includes a lead screw portion and a plain portion with a rotor magnet disposed thereon, and which has both ends thereof rotatably supported by respective bearings; and a thrust mechanism which includes a resilient member provided in a recess formed at one end of the rotary shaft positioned toward the lead screw portion, and adapted to give an axial thrust force to the rotary shaft, and a point-contact member provided between the resilient member and one bearing of the respective bearings, the one bearing rotatably supporting the one end of the rotary shaft positioned toward the lead screw portion. Thus, the thrust mechanism is located out of and apart from the stator assembly which includes coils to radiate heat, and therefore is prevented from suffering influences from the heat radiated by the coils.
    Type: Application
    Filed: October 12, 2004
    Publication date: October 26, 2006
    Inventors: Kunitake Matsushita, Takayuki Yamawaki, Toshihiko Nagata
  • Patent number: 7086303
    Abstract: A lead screw for a linear actuator, which has a metal pipe having a helical projection resin-molded on its outer surface, and a ball for a pivot bearing welded to a distal end of the metal pipe, is disclosed together with a method of manufacturing the same. With the lead screw according to this invention, a slight positional deviation from the origin, which is caused at a high ambient temperature by thermal expansion of a resin material filled up in the metal pipe, can be prevented reliably. Linear movement upon rotation of a stepping motor can take place with high precision.
    Type: Grant
    Filed: July 8, 2002
    Date of Patent: August 8, 2006
    Assignee: Minebea Co., Ltd.
    Inventor: Kunitake Matsushita
  • Patent number: 7071593
    Abstract: A claw-pole type stepping motor comprises: a rotor assembly shaped substantially cylindrical, and having a center shaft; and a stator assembly composed of two cup-shaped stator units which are coupled to each other coaxially so as to axially sandwich the rotor assembly, and which each include a bobbin having a magnet wire wound therearound, and two pole tooth arrays magnetically connected to each other and shifted in phase from each other by an electrical angle of 180 degrees. In the motor, each stator unit further includes a cover ring which protects the magnet wire wound around the bobbin against resin injected when the stator unit is resin-molded for an integrated solid structure. The motor structured as described above can be successfully resin-molded so as to enable elimination of a motor case, thus achieving downsizing for the dimension of the eliminated motor case while maintaining a sufficient mechanical strength.
    Type: Grant
    Filed: August 30, 2004
    Date of Patent: July 4, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Kunitake Matsushita, Takayuki Yamawaki, Toshihiko Nagata
  • Patent number: 7024957
    Abstract: A lead screw for a linear actuator, which has a metal pipe having a helical projection resin-molded on its outer surface, and a ball for a pivot bearing welded to a distal end of the metal pipe, is disclosed together with a method of manufacturing the same. With the lead screw according to this invention, a slight positional deviation from the origin, which is caused at a high ambient temperature by thermal expansion of a resin material filled up in the metal pipe, can be prevented reliably. Linear movement upon rotation of a stepping motor can take place with high precision.
    Type: Grant
    Filed: February 8, 2005
    Date of Patent: April 11, 2006
    Assignee: Minebea Co., Ltd.
    Inventor: Kunitake Matsushita
  • Publication number: 20060072433
    Abstract: A step portion (12) is formed on a table body (11) to be attached to a motor (20), and an ultraviolet curable adhesive as a resin (13) is applied to a mount-place forming position of the table body (11) including the step portion (12), and cured. The table body (11) is attached to the motor (20), and the surface of the resin (13) is cut while rotating a rotating shaft (21) of the motor (20). At this time, the step portion (12) prevents the peeling of the resin (13) against the force of moving the resin (13).
    Type: Application
    Filed: January 16, 2004
    Publication date: April 6, 2006
    Inventors: Kunitake Matsushita, Takayuki Yamawaki, Masaaki Inagaki, Katsutoshi Suzuki
  • Patent number: 7023115
    Abstract: In a motor, a shaft passes through a magnet of a rotor and is fixed to the magnet by way of a rotor sleeve formed by resin-molding between the magnet and the shaft. A resin-molded boss is fixed to a front end of a stator, has a center hole, and defines an inner surface continuous from the center hole and beveled so as to obliquely face a front end of the rotor sleeve. A plurality of bearing balls are rotatably disposed between the front end of the rotor sleeve and the beveled inner surface of the boss, thereby constituting a ball bearing which rotatably supports the shaft. Thus, the shaft is prevented from bowing, whereby the motor achieves a high rotational accuracy of the shaft without an additional bearing attached separately.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: April 4, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Kunitake Matsushita, Hiroshi Sano, Toshihiko Nagata
  • Patent number: 7023123
    Abstract: A motor has a hollow-cylindrical shaped rotary shaft provided with a hollow therein and is mounted on a PCB having an LED as light source. Light emitted from the LED passes through the hollow from one end of the rotary shaft to the other end, and irradiates an indicating needle attached to the other end of the rotary shaft.
    Type: Grant
    Filed: July 10, 2003
    Date of Patent: April 4, 2006
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Kunitake Matsushita
  • 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
  • Publication number: 20050218730
    Abstract: A low-profile stepping motor is disclosed, which is preferably used in downsized and lower-profiled electronic devices, such as a printer, a facsimile, a floppy disk drive, and the like. The motor comprises a stator assembly composed of first and second stator units (A, B) , and a rotor assembly (50) rotatably disposes inside the stator assembly. The stator units (A, B) are shaped and structured identically with each other, and each structured such that upper and lower stator yokes (30/32, 31/33) , which each have a plurality of pole teeth formed along one side, and which each have an exciting coil (40/42) disposed toward one side opposite to the one side having the pole teeth, are coupled to each other with their respective pole teeth intermeshing with each other with a shift of 180 degree electrical angle.
    Type: Application
    Filed: February 12, 2003
    Publication date: October 6, 2005
    Applicant: MINEBEA CO., LTD.
    Inventor: Kunitake Matsushita
  • Publication number: 20050223400
    Abstract: A spindle motor, in which the number of parts is kept from increasing and the number of assembling processes is reduced, and which has mechanisms for self-balancing and centrally aligning a disk, comprises a motor assembly (31) for rotating a disk (30) as a recording medium, a turntable (12) for mounting the disk (30), and a holder plate (14) disposed under the turntable (12). The mechanism for self-balancing is structured such that a plurality of steel balls (16) are disposed within an annular space (22) defined by the turntable (12) and the holder plate (14), and the mechanism for centrally aligning the disk (30) is constituted by a plurality of claw-shaped aligning members (5) formed at the inner circumference of the holder plate (14).
    Type: Application
    Filed: April 4, 2003
    Publication date: October 6, 2005
    Inventors: Kunitake Matsushita, Takayuki Yamawaki, Katsutoshi Suzuki, Masaaki Inagaki
  • Patent number: 6936768
    Abstract: A support hole, screw holes, and eleven orientating holes are formed in a plate. The orientating holes are each positioned asymmetric to any other thereof about a center of the plate.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: August 30, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Hideki Sakiyama, Hiroshi Sano, Kunitake Matsushita
  • Publication number: 20050139028
    Abstract: A lead screw for a linear actuator, which has a metal pipe having a helical projection resin-molded on its outer surface, and a ball for a pivot bearing welded to a distal end of the metal pipe, is disclosed together with a method of manufacturing the same. With the lead screw according to this invention, a slight positional deviation from the origin, which is caused at a high ambient temperature by thermal expansion of a resin material filled up in the metal pipe, can be prevented reliably. Linear movement upon rotation of a stepping motor can take place with high precision.
    Type: Application
    Filed: February 8, 2005
    Publication date: June 30, 2005
    Inventor: Kunitake Matsushita
  • Patent number: 6897592
    Abstract: A bobbin comprises: a bobbin body consisting generally of a cylinder having a winding of a magnet wire therearound, and two flanges; and a bobbin cover formed generally into a cylindrical ring. The bobbin body includes a coil termination block protruding radially from an inner flange of the two and having terminal pins for external connection, and the bobbin cover includes a termination protector protruding radially from the bobbin cover and adapted to mate with the coil termination block when the bobbin cover is put over the bobbin body.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: May 24, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Yuzuru Suzuki, Taketoshi Ohyashiki, Hiroshi Sano, Hideki Sakiyama, Kunitake Matsushita
  • Patent number: 6885128
    Abstract: A low-profile stepping motor has a stator assembly structured such that first and second coil units are disposed flush with each other horizontally and are sandwiched between upper and lower stator yoke pieces each comprising first and second stator yokes which are punched out integrally with each other, are shaped symmetrically, and which each have a plurality of pole teeth along its semi-circular inner circumference. The upper and lower stator yoke pieces are fixedly put together via the coils such that hollow-cylindrical protrusions formed in the upper and lower stator yoke pieces are inserted into through-holes of first and second coil bobbins from the upper and lower sides, respectively, and have their abutting end surfaces welded, bonded or otherwise fixed to each other, whereby the coil units are surely held between the upper and lower stator yoke pieces.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: April 26, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Kunitake Matsushita, Hiroshi Sano, Toshihiko Nagata
  • 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
  • Patent number: 6876109
    Abstract: A claw-pole type stepping motor comprises: a rotor which is shaped substantially cylindrical, and which has a rotary shaft at its radial center; and two stators which are shaped like a cup, each have at least one magnetic coil, are coupled to each other so as to rotatably house the rotor with their magnetic coils located respectively toward both axial end faces of the rotor, and which each have two pole tooth arrays magnetically connected to each other such that magnetic phase difference therebetween at tips of respective pole teeth is 180 degrees in terms of electrical angle, and in the motor thus structure, three pipes of aluminum go axially through the two stators so as to hold together the two stators.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: April 5, 2005
    Assignee: Minebea Co., Ltd.
    Inventors: Kunitake Matsushita, Takayuki Yamawaki, Toshihiko Nagata, Naoyuki Harada