Patents by Inventor Miyoko Hamao

Miyoko Hamao 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: 6599111
    Abstract: A vane pump comprising a pump housing, including an inlet, an outlet, and therein a hollow space, a cam ring received in the hollow space, a rotor placed in the cam ring and defining a rotation axis. The rotor comprises plural vanes arranged in corresponding slots formed in the rotor with a slidable contact in a radial direction of the rotor. A first wall member is received in the hollow space, one side of the first wall member faces one side of the cam ring, and the first wall member comprises an intake passage provided with a groove that is formed so that a partition wall portion is defined between the intake passage and an interface between the first wall member and the cam ring. A pair of intake ports are formed on the one side of the first wall member, each intake port is connected with the inlet by the intake passage, and a pair of outlet ports are formed on the one side of the first wall member.
    Type: Grant
    Filed: October 29, 2001
    Date of Patent: July 29, 2003
    Assignee: Unisia Jecs Corporation
    Inventors: Mizuo Ohtaki, Kazuyoshi Ishizaki, Yukio Uchida, Miyoko Hamao
  • Publication number: 20020051721
    Abstract: A vane pump comprising a pump housing, including an inlet, an outlet, and therein a hollow space, a cam ring received in the hollow space, a rotor placed in the cam ring and defining a rotation axis. The rotor comprises plural vanes arranged in corresponding slots formed in the rotor with a slidable contact in a radial direction of the rotor. A first wall member is received in the hollow space, one side of the first wall member faces one side of the cam ring, and the first wall member comprises an intake passage provided with a groove that is formed so that a partition wall portion is defined between the intake passage and an interface between the first wall member and the cam ring. A pair of intake ports are formed on the one side of the first wall member, each intake port is connected with the inlet by the intake passage, and a pair of outlet ports are formed on the one side of the first wall member.
    Type: Application
    Filed: October 29, 2001
    Publication date: May 2, 2002
    Applicant: UNISIA JECS CORPORATION
    Inventors: Mizuo Ohtaki, Kazuyoshi Ishizaki, Yukio Uchida, Miyoko Hamao
  • Patent number: 5613840
    Abstract: A pump comprising a pump body having a control valve for controlling working fluid flow from the pump body to an actuator through a joint. The joint is connected mechanically to the pump body through a washer made of a material different from that of the pump body. The washer has a side surface held in contact with the pump body at a junction. The pump also includes an annular seal member provided to keep the junction from exposure to the environment. In an embodiment of the invention, the seal member is placed in an annular groove formed in the outer peripheral surface of the pump body. The seal member may have a side surface in fluid-sealing contact with the surface of the washer so as to keep the junction between the pump body and the washer from exposure to the environment.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: March 25, 1997
    Assignee: Unisia Jecs Corporation
    Inventors: Kazuyoshi Ishizaki, Masateru Yamamuro, Atsushi Ishizuka, Shouji Ohya, Miyoko Hamao
  • Patent number: 5595478
    Abstract: A pump comprising a pump body having a control valve for controlling working fluid flow from the pump body to an actuator through a joint. The joint is connected mechanically to the pump body through a washer made of a material different from that of the pump body. The washer has a side surface held in contact with the pump body at a junction. The pump also includes an annular seal member provided to keep the junction from exposure to the environment. In an embodiment of the present invention (FIG. 7), an annular member is provided between the pump body and the washer, with the annular member being made of an insulating material to prevent electrical conduction between the pump body and the washer.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: January 21, 1997
    Assignee: Unisia Jecs Corporation
    Inventors: Kazuyoshi Ishizaki, Masateru Yamamuro, Atsushi Ishizuka, Shouji Ohya, Miyoko Hamao
  • Patent number: 5540566
    Abstract: A pump comprising a pump body having a control valve for controlling working fluid flow from the pump body to an actuator through a joint. The joint is connected mechanically to the pump body through a washer made of a material different from that of the pump body. The washer has a side surface held in contact with the pump body at a galvanic junction. The pump also includes an annular seal member provided to keep the junction from exposure to the environment.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: July 30, 1996
    Assignee: Unista Jecs Corporation
    Inventors: Kazuyoshi Ishizaki, Masateru Yamamuro, Atsushi Ishizuka, Shouji Ohya, Miyoko Hamao
  • Patent number: 5236315
    Abstract: A hydraulic pump of the rotary vane type comprises a first throttle bore and a second throttle bore disposed in parallel between a pressure chamber of the pump and a delivery passage, and a variable flow throttle valve is provided which is responsive to a difference between a vane back-up pressure and a pressure within the delivery passage to vary an opening degree of the first throttle bore.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: August 17, 1993
    Assignee: Atsugi Unisia Corporation
    Inventors: Miyoko Hamao, Kazuyoshi Ishizaki, Masahiko Hara
  • Patent number: 5170626
    Abstract: A hydraulic circuit supplies a controlled hydraulic flow rate to a hydraulically operated automotive component, such as, a power steering unit for satisfying the characteristic function thereof. The hydaulic circuit includes therein a flow control valve unit. In the flow control valve unit, throttle passages are provided each for throttling a hydraulic flow fed from a pump to increase its speed. Orifices are further provided in the flow control valve unit to regulate a hydraulic flow rate to be supplied toward the hydraulically operated automotive component. Each orifice functions to allow less hydraulic flow rate to pass therethrough toward the hydraulically operated automotive component corresponding to increasing speed of a hydraulic flow just upstream thereof.
    Type: Grant
    Filed: July 30, 1990
    Date of Patent: December 15, 1992
    Assignee: Atsugi Unisia Corporation
    Inventors: Mizuo Ohtaki, Miyoko Hamao
  • Patent number: 5141418
    Abstract: A variable capacity type vane pump comprising a cam ring, a rotor placed for rotation within the cam ring. The rotor has a number of radial slots, and vances placed for radial inward and outward movement in the receptive slots each having a bottom. A pump chamber is defined between the cam ring and the rotor and it has an inlet and outlet port. The outlet port is connected through a conduit to the bottom of at least one of the slots having vanes moving inwardly in the respective slots. A restriction orifice is placed in the conduit. The cam ring is moved with respect to the rotor to vary the capacity of the vane pump in response to a pressure differential across the restriction orifice.
    Type: Grant
    Filed: July 24, 1991
    Date of Patent: August 25, 1992
    Assignee: Atsugi Unisia Corporation
    Inventors: Mizuo Ohtaki, Teruhiko Mochizuki, Yoshio Okubo, Miyoko Hamao
  • Patent number: 5112199
    Abstract: A fluid pump unit has a flow control valve which returns a portion of a working fluid discharged from a pump assembly when rotation speed of a rotor increases to become greater than a predetermined value. The flow control valve includes an essentially cylindrical spool chamber defined in a pump case, and a valve spool movably housed within the spool chamber. The spool chamber has a pair of through openings on the side wall thereof which through openings are selectively open and closed by movement of the spool valve. The pump case is formed with a pair of drain passages which are respectively communicated with the through openings of the spool chamber independently of each other. When rotation speed of a rotor of the pump assembly becomes greater than a predetermined value, the spool valve opens the through openings to return a part of the discharged working fluid to an inlet passage through which working fluid is introduced from a fluid source into the pump assembly.
    Type: Grant
    Filed: September 25, 1990
    Date of Patent: May 12, 1992
    Assignee: Atsugi Unisia Corporation
    Inventors: Mizuo Otaki, Miyoko Hamao
  • Patent number: 5098259
    Abstract: A fluid pump has a pressure chamber communicated with a discharge outlet via an orifice. A pressure difference responsive flow control valve is also provided for adjustment fluid flow rate through the discharge outlet. The flow control valve has a valve spool housed within a spool chamber. The spool chamber has one end directly opening to the pressure chamber.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: March 24, 1992
    Assignee: Atsugi Unista Corporation
    Inventors: Mizuo Ohtaki, Miyoko Hamao