Patents by Inventor Jun-ichi Yasuma

Jun-ichi Yasuma 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: 5062454
    Abstract: A spool control valve in which communicating passages are provided in the spool to communicate between a pair of locations in the spool passage and filter means are provided in a communicating passage to prevent valve orifices being blocked by particles of foreign matter in the fluid.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: November 5, 1991
    Assignee: Diesel Kiki Co. L.T.D.
    Inventors: Koji Ichihashi, Jun-ichi Yasuma
  • Patent number: 4971114
    Abstract: An electromagnetic proportional pressure control valve includes a housing, and a spool slidably received in the housing. The spool has a pair of first and second pressure receiving portions which are equal to each other in effective pressure receiving area. A primary pressure in a primary port is applied to the first pressure receiving portion, and a secondary pressure in a secondary port is applied to the second pressure receiving portion. A form due to the primary pressure acts on the spool in a direction to increase the secondary pressure, and a force due to the secondary pressure acts on the spool in a direction to decrease the secondary pressure. A force of a spring and a force of an electromagnetic actuator also act on the spool in the opposite directions. A variation in the primary pressure directly appears in the secondary pressure.
    Type: Grant
    Filed: November 16, 1989
    Date of Patent: November 20, 1990
    Assignee: Diesel Kiki Co., Ltd.
    Inventors: Kouji Ichihashi, Jun-ichi Yasuma
  • Patent number: 4875501
    Abstract: An electromagnetic proportional control valve apparatus comprises a valve body, a spool accommodated in a guide bore in the valve body, a valve seat element arranged at one end of the guide bore and facing toward the spool, a pilot valve controlling a valve bore in the valve seat element, and an electromagnetic drive unit for controlling the pilot valve. The spool has an axially extending axial bore formed in an end face opposed to the valve seat element, and a first restricting bore through which the axial bore communicates with the supply port. A projecting portion is formed on an end face of the valve seat element opposed to the spool, and is inserted in the axial bore in the spool. The projecting portion has a forward part formed therein with second restricting bores through which one end of the valve bore communicates with the axial bore. A restricting passage is defined between an outer peripheral surface of the projecting portion and an inner peripheral surface of the axial bore in the spool.
    Type: Grant
    Filed: April 4, 1989
    Date of Patent: October 24, 1989
    Assignee: Diesel Kiki Co., Ltd.
    Inventors: Kouji Ichihashi, Jun-ichi Yasuma
  • Patent number: 4839509
    Abstract: A connector device for electrically connecting an IC card to a reading and/or writing apparatus. A first guide defining a transport path for the IC card is arranged within a casing having an insertion opening for the IC card. The transport path for the IC card extends from the insertion opening. A second guide extends in inclined relation to the transport path. A contact-probe support is guided by the second guide. The contact-probe support has supported thereon a plurality of contact probes projecting toward the first guide and an elastic arrangement biasing the contact probes toward the first guide. An abutment is associated with the contact-probe support and is arranged in crossing relation to the transport path.
    Type: Grant
    Filed: June 3, 1988
    Date of Patent: June 13, 1989
    Assignee: Diesel Kiki Co., Ltd.
    Inventors: Jun-ichi Yasuma, Tadashi Kobayashi, Masakuni Ishikawa