Patents by Inventor Yoshitaka Akiba

Yoshitaka Akiba 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: 7237515
    Abstract: A combustion-type power tool having a cooling arrangement for cooling a cylinder. The tool includes a housing, a cylinder head at one end of the housing, a push lever disposed at another end of the housing, and a combustion chamber frame including a base section and a head section. The head section has a disc like connecting portion extending from an end of the base section and a sleeve like abutment section extending from the connecting portion toward a cylinder head. A fan is disposed in a combustion chamber and is fixed to a rotation shaft of a motor supported to the cylinder head. The fan has fan blades. The fan blades define a widthwise center line in the axial direction of the rotation shaft. The center line is offset from the connecting portion and toward the push lever. The fan blades define widthwise edges in confrontation with the cylinder head. The widthwise edge is positioned in alignment with the connecting portion or offset therefrom toward the cylinder head.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: July 3, 2007
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Haruhisa Fujisawa
  • Publication number: 20070138231
    Abstract: A combustion-type power tool includes a housing, a head section, a cylinder, a nose extending downwardly from a lower end portion of the cylinder, a push lever, a piston, a combustion-chamber frame movably provided in the housing so as to abut the head section at a first position and to be separated from the head section at a second position, and a connection unit for mechanically associating the push lever with the combustion chamber frame. The connection unit includes at least two arms, and a connector section connected with the push lever and having a first plate portion and a second portion extending from the first plate portion. Each of the at least two arms is connected at one end with the combustion chamber frame and at another end with the second portion of the connection section.
    Type: Application
    Filed: February 13, 2007
    Publication date: June 21, 2007
    Inventor: Yoshitaka Akiba
  • Patent number: 7225768
    Abstract: A combustion type power tool having an arrangement avoiding direct striking of a drive shaft against a cylinder head when combustion pressure is exerted. A motor is disposed at the cylinder head and includes a motor body and a drive shaft extending in an axial direction and protruding into a combustion chamber. A fan is connected to the drive shaft to be rotatable within the combustion chamber. A buffer piece made from an elastic material is supported to the cylinder head. The buffer piece is movable relative to the cylinder head in a direction substantially perpendicular to the axial direction. The buffer piece is formed with a through-hole through which the drive shaft extends.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: June 5, 2007
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshitaka Akiba, Haruhisa Fujisawa, Tomomasa Nishikawa
  • Patent number: 7210431
    Abstract: A combustion-type power tool includes a cylinder and a combustion chamber frame disposed to surround the cylinder and movable along the cylinder. A partition wall divides an inner space of an outer frame into a first space in which the cylinder and the combustion chamber frame are disposed and a second space in which a gas cartridge cylinder is disposed and has a through-hole through which the first space and the second space are in fluid communication with each other. A plurality of ribs is formed on an outer surface of the cylinder for regulating an exhaust gas flow generated by combustion of a gaseous mixture in the combustion chamber. The ribs enable exhaust gas discharged from the combustion chamber to be directed away from the through-hole, thereby enabling the gas cartridge cylinder to be maintained at a substantially constant temperature.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: May 1, 2007
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Shoichi Hirai, Haruhisa Fujisawa
  • Patent number: 7182237
    Abstract: A combustion type power tool providing enhanced workability and improved material yieldability. A combustion chamber frame is slidably movably disposed in a housing. A push lever is slidably movably supported to a nose extending from a lower end portion of the housing, and is abuttable on a workpiece. The combustion chamber frame and the push lever are associated with each other by a connection unit including arm sections and a connector section. A compression coil spring for biasing the push lever downwardly is interposed between the connector section and a cylinder disposed in the housing. The housing covers the entire arm sections, the connector section and the spring, so that these components are not directly accessible from an outside.
    Type: Grant
    Filed: January 11, 2005
    Date of Patent: February 27, 2007
    Assignee: Hitachi Koki Co., Ltd.
    Inventor: Yoshitaka Akiba
  • Publication number: 20070034661
    Abstract: A combustion-type power tool includes a housing, a cylinder head disposed at one end of the housing, a cylinder in the housing, a piston slidably disposed in the cylinder, and a driver blade connected to the piston. A combustion-chamber is provided in the housing, a fan is disposed in the combustion chamber, and a motor having an output shaft is coupled to the fan. A motor holder accommodates the motor, and the cylinder head is formed with a motor holder receiving portion in which the motor holder is slidably movably disposed. An elastic member is disposed in a gap formed between the motor holder and the motor holder receiving portion.
    Type: Application
    Filed: October 4, 2006
    Publication date: February 15, 2007
    Inventors: Yoshitaka Akiba, Tomomasa Nishikawa, Kunio Yamamoto, Shinki Ohtsu, Haruhisa Fujisawa
  • Publication number: 20060249107
    Abstract: A combustion-type power tool includes a frame comprising a housing having one end, and a head portion disposed at the one end, and a piston reciprocally movably disposed in the housing. A combustion chamber is provided in the housing and has one end movable toward and away from the head portion and another end defined by the piston. A motor is provided and has a motor case disposed opposite to the combustion chamber with respect to the head portion, a buffer member is provided which supports the motor and has a part located between the motor case and the head portion.
    Type: Application
    Filed: July 3, 2006
    Publication date: November 9, 2006
    Inventors: Yoshitaka Akiba, Haruhisa Fujisawa
  • Patent number: 7131404
    Abstract: A combustion-type power tool having a cooling arrangement for cooling a gas canister. The tool includes a housing having a gas canister accommodating section in which a gas canister is accommodated. An air passage is defined between the gas canister accommodating section and the gas canister accommodated therein. The gas canister accommodating section is formed with an air inlet port in communication with the air passage for introducing air into the air passage. Since air flows along the gas canister, the gas canister can be cooled. If the tool is provided with a fan, the rotation of the fan causes air suction passing through the air passage.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: November 7, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Shoichi Hirai, Haruhisa Fujisawa
  • Patent number: 7121442
    Abstract: A combustion-type nail driver uses a motor for driving a fan. A motor holder formed from plastic accommodates the motor. A cylinder head has a motor holder receiving portion in which the motor holder is slidably movably disposed. A coil spring has one end secured to the motor holder and another end secured to the cylinder head to thereby support the motor holder. Initial acceleration applied to the motor when combustion occurs can be suppressed and impact imparted upon the motor can also be suppressed by friction between the outer periphery of the motor holder and the inner periphery of the motor holder receiving portion. A heat shielding plate is interposed between the lower end surface of the motor and the cylinder head in order to prevent hot air combustion gas from entering into the motor.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: October 17, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshitaka Akiba, Tomomasa Nishikawa, Kunio Yamamoto, Shinki Ohtsu, Haruhisa Fujisawa
  • Publication number: 20060225675
    Abstract: A combustion-type power tool includes a housing, a head portion, a cylinder disposed in the housing, and a push lever. A piston is reciprocally movable in the cylinder, and a combustion-chamber frame is disposed in the housing and abuttable on the head portion to provide a combustion chamber in cooperation with the head portion and the piston. A fuel supplying portion supplies the fuel into the combustion chamber, a motor is disposed at the head portion, and a fan is disposed in the combustion chamber and connected to an output shaft of the motor so as to promote turbulent combustion of an air-fuel mixture. The fan and the combustion-chamber frame define a high turbulent-combustion region and a low turbulent-combustion region, a fin of one shape is located within the low turbulent-combustion region, and another fin of another shape has a part thereof located in the high turbulent-combustion region.
    Type: Application
    Filed: June 8, 2006
    Publication date: October 12, 2006
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Haruhisa Fujisawa
  • Publication number: 20060225676
    Abstract: A combustion-type power tool includes a housing having one end, a head portion disposed at the one end, and a cylinder disposed in the housing, the cylinder being formed with an exhaust hole. A piston is reciprocally movable in the cylinder, and a combustion-chamber frame is disposed in the housing and movable in an axial direction of the cylinder, the combustion-chamber frame being abuttable on the head portion to provide a combustion chamber in cooperation with the head portion and the piston. A fin is disposed on the cylinder and has a portion extending in a direction slanted in relation to the axial direction and oriented toward the exhaust hole.
    Type: Application
    Filed: June 8, 2006
    Publication date: October 12, 2006
    Inventors: Shoichi Hirai, Yoshitaka Akiba, Tomomasa Nishikawa
  • Publication number: 20060186166
    Abstract: A combustion-type power tool includes a cylinder, a piston, a head, a combustion chamber frame, an ignition unit, a trigger, a control member. The combustion chamber frame is abuttable on the head to provide a combustion chamber in cooperation with the head and the piston. The trigger is operated by a user for driving the fastener into a workpiece. The control member detects that the combustion chamber has been provided and the trigger has been operated, and allows the ignition unit to ignite the combustible gas only when the control member detects that both the combustion chamber has been provided and the trigger has been operated.
    Type: Application
    Filed: February 17, 2006
    Publication date: August 24, 2006
    Inventor: Yoshitaka Akiba
  • Publication number: 20060185630
    Abstract: A main switch section is accommodated in a trigger. The trigger provided on the handle through a spring. The handle is formed with a recess to which one end of the spring is seated, so that the trigger is normally urged toward the lower side of the combustion-type nail driver. A switch accommodating portion is provided in the lower side of the canister housing. A push switch is stored in the switch accommodating portion.
    Type: Application
    Filed: February 17, 2006
    Publication date: August 24, 2006
    Inventors: Haruhisa Fujisawa, Yoshitaka Akiba
  • Publication number: 20060186165
    Abstract: In the combustion-type power tool, a first shelter wall and a second shelter wall are disposed to partially surround an area between an ignition plug and an ignition ground. Two gaps are provided between the first and second shelter walls. The first shelter wall extends radially outwardly from an outer peripheral surface of a motor boss, and also protrudes from an end face in an axial direction of a fan shaft. The first shelter wall has a lower end surface inclined such that an axial length between the end face and the lower end surface is gradually reduced toward radially outer end of the first shelter wall.
    Type: Application
    Filed: February 17, 2006
    Publication date: August 24, 2006
    Inventors: Tomomasa Nishikawa, Yasuki Ohmori, Shinki Ohtsu, Kunio Yamamoto, Yoshitaka Akiba, Haruhisa Fujisawa
  • Patent number: 7073468
    Abstract: A combustion type power tool having a motor suspension arrangement capable of buffering a shock applied to a motor. An integral buffer member made from an elastic material is fixed to a head cap. The buffer member includes a motor storage section in which a motor casing is stored, and a plurality of buffer segments extending radially outwardly from the motor storage section and integrally therewith. Each radially outer end portion of each buffer segment is fixed to the head cap for floatingly supporting the motor storage section.
    Type: Grant
    Filed: April 4, 2005
    Date of Patent: July 11, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yoshitaka Akiba, Haruhisa Fujisawa
  • Publication number: 20060144889
    Abstract: A combustion-type power tool includes a cylinder and a combustion chamber frame disposed to surround the cylinder and movable along the cylinder. A combustion chamber is formed on top of the cylinder that accommodates a gaseous mixture of existing air in the combustion chamber and fuel injected therein from a gas cylinder. A spark plug generates a spark to combust the gaseous mixture in the combustion chamber. A trigger switch produces the spark in the spark plug when operated. A piston slidably moves along the inner surface of the cylinder and driven by combustion in the combustion chamber. A driving blade is secured to the piston for driving a fastener. A partition wall divides the inner space of the outer frame into a first space in which the cylinder and the combustion chamber frame are disposed and a second space in which the gas cylinder is disposed. The partition wall is formed with a through-hole through which the first space and the second space are in fluid communication with each other.
    Type: Application
    Filed: December 20, 2005
    Publication date: July 6, 2006
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Shoichi Hirai, Haruhisa Fujisawa
  • Patent number: 7063053
    Abstract: A combustion-type power tool includes a cylinder having a peripheral wall which has an inner peripheral surface and an outer peripheral surface. The peripheral wall is formed with an exhaust hole at a first axial position. A piston is reciprocally movable in an axial direction and is slidable in contact with the inner peripheral surface. A combustion-chamber frame is abuttable on a head portion to provide a combustion chamber in cooperation with the head portion and the piston. The piston allows the combustion chamber to be in fluid communication with an atmosphere through an upper space above the piston and through the exhaust hole when the piston is located at a bottom dead center. The fin is disposed at the outer peripheral surface and has a portion extending in a direction slanted in relation to the axial direction and oriented toward the exhaust hole.
    Type: Grant
    Filed: May 5, 2005
    Date of Patent: June 20, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Shoichi Hirai, Yoshitaka Akiba, Tomomasa Nishikawa
  • Patent number: 7063052
    Abstract: A combustion-chamber frame is disposed in a housing of a combustion-type power tool and is movable in a longitudinal direction in interlocking relation to a push lever. The combustion-chamber frame is abuttable on a head portion to provide a combustion chamber in cooperation with the head portion and a piston. A fan is disposed in the combustion chamber and is connected to an output shaft of a motor so as to be rotatable with the output shaft for promoting turbulent combustion of air-fuel mixture. The fan and the combustion-chamber frame define, within the combustion chamber, a high turbulent-combustion region in which the turbulent combustion is rapidly generated and a low turbulent-combustion region outside the high turbulent-combustion region. A fin is disposed at at least one of the combustion-chamber frame, the head portion, and the piston to protrude into the combustion chamber. The fin is located within the low turbulent-combustion region.
    Type: Grant
    Filed: May 4, 2005
    Date of Patent: June 20, 2006
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Haruhisa Fujisawa
  • Publication number: 20060065690
    Abstract: A combustion-powered, fastener-driving tool includes a cylinder and a combustion chamber disposed on top of the cylinder that accommodates a gaseous mixture of existing air in the combustion chamber and fuel injected therein. A spark plug generates a spark to combust the gaseous mixture in the combustion chamber. A trigger produces the spark in the spark plug when operated. A piston is movably supported in the cylinder and driven by combustion in the combustion chamber. A driving blade is coupled to the piston for driving a fastener. A spark controller is provided for generating a plurality of sparks in succession with the spark plug.
    Type: Application
    Filed: September 29, 2005
    Publication date: March 30, 2006
    Inventors: Haruhisa Fujisawa, Yoshitaka Akiba, Nobuhiro Takano, Kenro Ishimaru, Tomomasa Nishikawa
  • Publication number: 20060042572
    Abstract: A combustion-type power tool having a cooling arrangement for cooling a gas canister. The tool includes a housing having a gas canister accommodating section in which a gas canister is accommodated. An air passage is defined between the gas canister accommodating section and the gas canister accommodated therein. The gas canister accommodating section is formed with an air inlet port in communication with the air passage for introducing air into the air passage. Since air flows along the gas canister, the gas canister can be cooled. If the tool is provided with a fan, the rotation of the fan causes air suction passing through the air passage.
    Type: Application
    Filed: August 23, 2005
    Publication date: March 2, 2006
    Inventors: Tomomasa Nishikawa, Yoshitaka Akiba, Shoichi Hirai, Haruhisa Fujisawa