Patents by Inventor Shuji Tajima

Shuji Tajima 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).

  • Publication number: 20240133442
    Abstract: A spring member is provided between two pressed bodies facing each other in a first direction and includes base plates stacked in the first direction. Each base plate is provided with spring protrusions protruding toward either one pressed body of the two pressed bodies and pressing the two pressed bodies in directions such that the pressed bodies move away from each other in the first direction. Between two base plates adjacent to each other in the first direction, a base plate positioned closer to the one pressed body is provided with an insertion hole into which a spring protrusion of the other base plate is inserted in a state of penetrating therethrough in the first direction. Among portions in an along-plane direction along a plane orthogonal to the first direction provided with the spring protrusions, the spring constant of at least one portion is different from that of another portion.
    Type: Application
    Filed: February 25, 2022
    Publication date: April 25, 2024
    Inventors: Yoshio YAMADA, Hironobu IMAIZUMI, Norihiro TAJIMA, Shuji TAKAHASHI
  • Publication number: 20100297488
    Abstract: Provided is an explosion-proof structure of a power source part, an explosion-proof type battery unit and an explosion-proof type gas alarm, in which the degree of temperature rise upon short circuit of a secondary battery is reduced and explosion-proof performance with high reliability is achieved. The explosion-proof structure of a power source in an explosion-proof type apparatus employing a secondary battery as a power source for driving is fabricated by arranging a heat-radiating member composed of a metal at an outer peripheral surface of the secondary battery in a state that at least a part thereof comes into close contact with the surface. The explosion-proof type battery unit is composed of a cylindrical secondary battery and a heat-radiating member composed of a metal provided at an outer peripheral surface of the secondary battery in a state that at least a part thereof comes into close contact with the surface.
    Type: Application
    Filed: January 26, 2009
    Publication date: November 25, 2010
    Applicant: Riken Keiki Co., Ltd.
    Inventors: Shuji Tajima, Haruhiko Kondo, Masahide Kitamura, Kei Ono
  • Patent number: 7178381
    Abstract: The invention provides a portable gas detector which is equipped with filters for removal of interfering gases, high in convenience for use, easy to exchange the filters, and easy to confirm the time the filters are exchanged. The portable gas detector has a housing in the form of a slim and flat box holdable by grasping with a hand, and a foreside half portion in the interior of the housing is provided as functional part region, in which a plurality of gas sensors are arranged in a state fixed by a holder and a cap, in the interior of which a gas flowing path has been formed. At a position corresponding to at least one gas sensor in the sensor cap exposed to the back surface of the housing, a filter assembly for removal of an interfering gas component related to the gas sensor is detachably provided.
    Type: Grant
    Filed: August 9, 2004
    Date of Patent: February 20, 2007
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Shuji Tajima, Yasunori Takei
  • Patent number: 7089779
    Abstract: The invention provides a portable gas detector of a novel structure that is easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas detector has a housing in the form of a slim and flat box holdable by grasping with a hand, and a foreside half portion in the interior of he housing is provided as a functional part region, and a rear half portion in the interior of the housing is provided as a battery part region. In the functional part region, one of 5 gas sensors is arranged at a curved portion in a gas sensor-arranging region of an L shape as a whole, and 2 gas sensors are arranged in a row in both lateral and vertical directions of the above gas sensor, respectively. A gas sucking means is arranged in a region, the 2 directions of which is sectioned by the gas sensor-arranging region.
    Type: Grant
    Filed: August 9, 2004
    Date of Patent: August 15, 2006
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Shuji Tajima, Yasunori Takei
  • Patent number: 7086283
    Abstract: The invention provides an explosion-proof portable gas detector that is easy to be fabricated as a small-sized one handy to carry and high in convenience for use, and has explosion-proofness sufficient in a countermeasure against static electricity and high in reliability. The explosion-proof portable gas detector has at least gas sensors, a signal processing circuit, a display mechanism and a power source part within a housing in the form of a slim and flat box holdable by grasping with a hand. The whole or a part of the housing is formed of a static charge-controlling resin material having an insulating resistance value of at most 1 G? and a comparative tracking index of at least 90 V.
    Type: Grant
    Filed: July 15, 2004
    Date of Patent: August 8, 2006
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Junichi Koyano, Shuji Tajima
  • Publication number: 20060010974
    Abstract: The invention provides an explosion-proof portable gas detector that is easy to be fabricated as a small-sized one handy to carry and high in convenience for use, and has explosion-proofness sufficient in a countermeasure against static electricity and high in reliability. The explosion-proof portable gas detector has at least gas sensors, a signal processing circuit, a display mechanism and a power source part within a housing in the form of a slim and flat box holdable by grasping with a hand. The whole or a part of the housing is formed of a static charge-controlling resin material having an insulating resistance value of at most 1 G? and a comparative tracking index of at least 90 V.
    Type: Application
    Filed: July 15, 2004
    Publication date: January 19, 2006
    Applicant: RIKEN KEIKI CO., LTD.
    Inventors: Junichi Koyano, Shuji Tajima
  • Publication number: 20050092065
    Abstract: The invention provides a portable gas detector of a novel structure that is easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas detector has a housing in the form of a slim and flat box holdable by grasping with a hand, and on the front side in the interior of the housing a circuit board for control is arranged so as to extend along a flat plane direction of the housing. A foreside half portion in the interior of the housing is provided as a functional part region, in which functional members related to a gas detecting operation are arranged, and a rear half portion is provided as a battery part region, in which either one of 3 rod-like dry cells or a chargeable battery pack formed by holding 3 chargeable batteries having the same external shape as the dry cell by a holding frame member in a state arranged in parallel is installed exchangeably with the other.
    Type: Application
    Filed: August 9, 2004
    Publication date: May 5, 2005
    Applicant: Riken Keiki Co., Ltd.
    Inventors: Shuji Tajima, Yasunori Takei
  • Publication number: 20050092063
    Abstract: The invention provides a portable gas detector of a novel structure that is easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas detector has a housing in the form of a slim and flat box holdable by grasping with a hand, and a foreside half portion in the interior of he housing is provided as a functional part region, and a rear half portion in the interior of the housing is provided as a battery part region. In the functional part region, one of 5 gas sensors is arranged at a curved portion in a gas sensor-arranging region of an L shape as a whole, and 2 gas sensors are arranged in a row in both lateral and vertical directions of the above gas sensor, respectively. A gas sucking means is arranged in a region, the 2 directions of which is sectioned by the gas sensor-arranging region.
    Type: Application
    Filed: August 9, 2004
    Publication date: May 5, 2005
    Applicant: Riken Keiki Co., Ltd.
    Inventors: Shuji Tajima, Yasunori Takei
  • Publication number: 20050092064
    Abstract: The invention provides a portable gas detector which is equipped with filters for removal of interfering gases, high in convenience for use, easy to exchange the filters, and easy to confirm the time the filters are exchanged. The portable gas detector has a housing in the form of a slim and flat box holdable by grasping with a hand, and a foreside half portion in the interior of the housing is provided as functional part region, in which a plurality of gas sensors are arranged in a state fixed by a holder and a cap, in the interior of which a gas flowing path has been formed. At a position corresponding to at least one gas sensor in the sensor cap exposed to the back surface of the housing, a filter assembly for removal of an interfering gas component related to the gas sensor is detachably provided.
    Type: Application
    Filed: August 9, 2004
    Publication date: May 5, 2005
    Applicant: Riken Keiki Co., Ltd.
    Inventors: Shuji Tajima, Yasunori Takei
  • Patent number: 6744373
    Abstract: Disclosed is a portable gas alarm device easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas alarm device comprises a gas alarm device body having a casing flat in whole and a fitting member provided on the casing to fit it to the human body. The gas alarm device body has a control circuit board extending to the direction of the flat plane of the casing, a display mechanism is arranged in a central area on the front surface side of the control circuit board, a gas sensor and an alarm buzzer are arranged on the right and left sides of the display mechanism, and a battery fitting chamber is provided on the back surface side of the circuit board. A vibration generator for alarm may be provided in the gas alarm device body. The fitting member may be one suitable for use in fitting the gas alarm device body to a person's wrist or a person's wear.
    Type: Grant
    Filed: March 25, 2002
    Date of Patent: June 1, 2004
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Junichi Koyano, Shuji Tajima, Yoshiharu Ao, Masahide Kitamura
  • Patent number: 6712586
    Abstract: The invention provides a gas suction pump device equipped with a casing having a substantially rectangular frame-like sectional shape and formed slenderly in a gas flowing direction and into a size holdable by grasping with a hand, a control circuit board provided in the casing so as to extend in a longitudinal direction along the upper wall of the casing, a pump unit arranged in a region on the side of one side wall on the lower side of the control circuit board in a state that one end and the other end of a gas flow path defined by the pump unit have been connected to a gas inlet port and a gas outlet port, respectively, and a battery fitting chamber provided in a region on the side of the other side wall. The invention also provides a gas alarm unit constructed by connecting the above pump device to a portable gas alarm device provided with a specific gas feed adapter through a connecting tube.
    Type: Grant
    Filed: July 22, 2002
    Date of Patent: March 30, 2004
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Junichi Koyano, Shuji Tajima, Yasunori Takei, Takuo Aida
  • Patent number: 6606897
    Abstract: A portable gas detector comprises a casing proper 1 adapted to be attached to the human body. The casing proper 1 has multiple openings to accommodate gas sensors 5 on one side and charging terminals 38 and a communication window 14 on the other. Calibration of the gas sensors and securing of power supply are easy to achieve.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: August 19, 2003
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Juniti Koyano, Shuji Tajima, Masahide Kitamura
  • Publication number: 20030138329
    Abstract: The invention provides a gas suction pump device equipped with a casing having a substantially rectangular frame-like sectional shape and formed slenderly in a gas flowing direction and into a size holdable by grasping with a hand, a control circuit board provided in the casing so as to extend in a longitudinal direction along the upper wall of the casing, a pump unit arranged in a region on the side of one side wall on the lower side of the control circuit board in a state that one end and the other end of a gas flow path defined by the pump unit have been connected to a gas inlet port and a gas outlet port, respectively, and a battery fitting chamber provided in a region on the side of the other side wall. The invention also provides a gas alarm unit constructed by connecting the above pump device to a portable gas alarm device provided with a specific gas feed adapter through a connecting tube.
    Type: Application
    Filed: July 22, 2002
    Publication date: July 24, 2003
    Applicant: Riken Keiki Co., Ltd.
    Inventors: Junichi Koyano, Shuji Tajima, Yasunori Takei, Takuo Aida
  • Publication number: 20030052792
    Abstract: Disclosed is a portable gas alarm device easy to be fabricated as a small-sized one handy to carry and high in convenience for use. The portable gas alarm device comprises a gas alarm device body having a casing flat in whole and a fitting member provided on the casing to fit it to the human body. The gas alarm device body has a control circuit board extending to the direction of the flat plane of the casing, a display mechanism is arranged in a central area on the front surface side of the control circuit board, a gas sensor and an alarm buzzer are arranged on the right and left sides of the display mechanism, and a battery fitting chamber is provided on the back surface side of the circuit board. A vibration generator for alarm may be provided in the gas alarm device body. The fitting member may be one suitable for use in fitting the gas alarm device body to a person's wrist or a person's wear.
    Type: Application
    Filed: March 25, 2002
    Publication date: March 20, 2003
    Applicant: Riken Keiki Co., Ltd.
    Inventors: Junichi Koyano, Shuji Tajima, Yoshiharu Ao, Masahide Kitamura
  • Patent number: D447974
    Type: Grant
    Filed: October 17, 2000
    Date of Patent: September 18, 2001
    Assignee: Riken Keiki Co., Ltd.
    Inventors: Juniti Koyano, Shuji Tajima, Masahide Kitamura