Patents by Inventor Naotoshi Tamai

Naotoshi Tamai 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: 7273003
    Abstract: A plunger pump, includes: a plunger pump unit including a pump chamber and a plunger for pressing a hydraulic fluid in the pump chamber to perform a discharging operation of the hydraulic fluid; a motor; and a cam portion driven by the motor to rotate and press the plunger. The cam portion has at least two discharge regions for pressing the plunger and a suction region formed between the discharge region. The plunger performs the discharging operation two times or more by one rotation of the cam portion.
    Type: Grant
    Filed: June 2, 2004
    Date of Patent: September 25, 2007
    Assignee: Nissin Kogyo Co., Ltd.
    Inventors: Jun Yamashita, Tomohide Tanaka, Atsushi Shimizu, Naotoshi Tamai, Motoyasu Nakamura
  • Publication number: 20050002809
    Abstract: A plunger pump, includes: a plunger pump unit including a pump chamber and a plunger for pressing a hydraulic fluid in the pump chamber to perform a discharging operation of the hydraulic fluid; a motor; and a cam portion driven by the motor to rotate and press the plunger. The cam portion has at least two discharge regions for pressing the plunger and a suction region formed between the discharge region. The plunger performs the discharging operation two times or more by one rotation of the cam portion.
    Type: Application
    Filed: June 2, 2004
    Publication date: January 6, 2005
    Inventors: Jun Yamashita, Tomohide Tanaka, Atsushi Shimizu, Naotoshi Tamai, Motoyasu Nakamura
  • Patent number: 6238014
    Abstract: An electromagnetic valve is fitted with relief means and is made to have a compact diameter without increasing its axial length is provided. The electromagnetic valve is provided with a push bar capable of pushing the valve body toward the valve seat and a relief spring for urging the push bar toward the valve body are contained in a guide hole formed in the central portion of the moving core, wherein a stopper is provided to the moving core, the stopper being used for holding the valve body open by defining a limit to which the push bar is moved forward with respect to the valve body when the moving core is moved backward and for allowing the valve body to be closed by the relief spring when the moving core is moved forward. Thus, the valve body and the push bar are axially arranged separately from each other.
    Type: Grant
    Filed: April 20, 1999
    Date of Patent: May 29, 2001
    Assignee: Nissin Kogyo Co., Ltd.
    Inventors: Naotoshi Tamai, Takaomi Sirase, Naoki Masuda, Makoto Kikuchi
  • Patent number: 6163093
    Abstract: A pump actuation motor includes a yoke (15), a rotation shaft (12) that has, on one end side, a supported shaft portion (12d) that is inserted into and supported by a block body (9) and an eccentric shaft portion (12c) that actuates the plunger pumps (5) and (6) and, on the other end side, a rotor and a commutator (22) attached therearound, a brush holder (23) that holds a brush (24) that can supply electric power from-the block body (9) side to the commutator (22), and a housing (26) that is so mounted between the yoke (15) and the block body (9)side as to cover an opening of such yoke (15), wherein the rotation shaft (12) includes a recessed portion (12a) that opens on an end surface of the other end side while the yoke (15) includes a protruding portion 15a that protrudes into the recessed portion (12a) that is formed as a part of such yoke (15), and the other end side of the rotation shaft (12) is supported by such protruding portion (15a).
    Type: Grant
    Filed: February 15, 2000
    Date of Patent: December 19, 2000
    Assignee: Nissin Kogyo Co., Ltd.
    Inventors: Atsushi Shimizu, Takuya Maruo, Naotoshi Tamai
  • Patent number: 5887624
    Abstract: An electromagnetic valve device includes a valve operating unit formed by disposing valve components in a valve housing having a guide cylinder and mounted to a base member, and a tip end of the guide cylinder and a housing body are magnetically connected to each other by a magnetic path defining frame surrounding a coil wound around a bobbin. The bobbin is buried in a mold section made of synthetic resin to form a coil unit. The coil unit is mounted to the base member. One end of the magnetic path defining frame is formed with a fitting bore through which the tip end of the guide cylinder is fitted, and the other end of the magnetic path defining frame is capable of abutting against the housing body. The magnetic path defining frame is mounted to a coil-correspondence portion of the mold section. The guide cylinder is loosely passed through a center bore of the bobbin.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: March 30, 1999
    Assignees: Kabushiki Kaisha Honda Lock, Nissin Kogyo Co., Ltd.
    Inventors: Takeshi Taniguchi, Akira Fujimoto, Tsutomu Kurita, Takaomi Shirase, Naotoshi Tamai
  • Patent number: 5836354
    Abstract: A hydraulic pressure controller includes: a base; a n electromagnetic valve mounted on the base and including a guide cylinder protruding from the base, a coil unit having a bobbin surrounding the guide cylinder and a coil wound on the bobbin, and a magnetic path forming frame connecting magnetically a first end and a second end of the guide cylinder; a reservoir and a damper arranged with the electromagnetic valve on the base; and a cover covering the electromagnetic valve, the reservoir and the damper, in which the cover includes a frame coupled to the base, the frame surrounding the electromagnetic valve, and a skirt portion formed integrally with the frame, the skirt portion covering the reservoir and the damper. The hydraulic pressure controller is light in weight and is improved in assembling efficiency. The hydraulic pressure controller has a reservoir water-proofing structure which is capable of preventing water from entering an outside air communicating chamber of the reservoir.
    Type: Grant
    Filed: October 22, 1996
    Date of Patent: November 17, 1998
    Assignee: Nissin Nogyo Co., Ltd.
    Inventors: Tsutomu Amano, Naotoshi Tamai, Takashi Aoki, Takaomi Shirase
  • Patent number: 5634695
    Abstract: In a hydraulic apparatus providing a base with a discharge passage coupler to a circumferential portion of an annular discharge passage and to a damper chamber, a hydraulic device is connected via an orifice to the discharge passage without arranging the annular discharge passage between the damper chamber and the orifices, so that the damper chamber and the orifices cooperate together to exert an effective attenuating action thereon so as to suppress the transfer of pressure pulsation thereto effectively.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: June 3, 1997
    Assignee: Nissin Kogyo Co., Ltd.
    Inventors: Kazuhiro Ohta, Naotoshi Tamai, Atsushi Shimizu, Takashi Aoki
  • Patent number: 5174635
    Abstract: In a hydraulic braking pressure control system for a rear wheel brake wherein a control piston normally works to provide a hydraulic braking pressure control by cooperation with a cut-off valve interposed between an input chamber leading to a master cylinder and an output chamber leading to a wheel cylinder of the brake, the cut-off valve has a valve seat piston whose pressure-receiving area facing the output chamber is larger than the pressure-receiving area facing the output chamber. This ensures that opening and closing of the cut-off valve can be repeated in accordance with the output pressure from the master cylinder, so that the output pressure from the master cylinder can be reduced and applied to the brake wheel cylinder.
    Type: Grant
    Filed: September 20, 1991
    Date of Patent: December 29, 1992
    Assignees: Nissin Kogyo Co., Ltd., Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Naotoshi Tamai, Yoichi Sugimoto, Yoshihiro Iwagawa, Kougyoku Go
  • Patent number: 5100211
    Abstract: A hydraulic braking pressure control system which includes a sleeve slidably received in a housing with opposite ends facing an output chamber connected to a brake device, and a pilot chamber connected to a control hydraulic pressure source. A control piston is slidably received in the sleeve, with one end of the control piston facing the output chamber and the other end facing a control chamber connected to the control hydraulic pressure source through a lock valve which is adapted to be closed in response to the movement of the sleeve, in a direction to increase the volume of the output chamber. A cut-off valve located between an input chamber leading to a master cylinder and the output chamber includes a valve member having a maximum amount of movement in a seating direction which is regulated to a position of the valve member spaced apart from a valve seat when a valve seat member follows movement of the sleeve in a direction to reduce the volume of the pilot chamber to the maximum amount.
    Type: Grant
    Filed: November 13, 1990
    Date of Patent: March 31, 1992
    Assignees: Honda Giken Kogyo Kabushiki Kaisha, Nissin Kogyo Kabushiki Kaisha
    Inventors: Yoichi Sugimoto, Kougyoku Go, Yoshihiro Iwagawa, Etsuo Fujii, Naotoshi Tamai, Atsushi Shimizu