Hitachi Koki Co., Ltd.

Yasuyuki Hirano

Akira Uno

Shinki Ohtsu

Yasuki Ohmori

Takuji Torii

Isamu Tanji

Toshifumi Kubota

Yo Kawakami

Teruo Suzuki

Taiichi Kumasaka

Hiromu Utsumi

Tsunehisa Terayama

Satoshi Kuno

Koichi Sawada

Katsuhiko Ozaki

A pneumatically operated screw driver having a pneumatically operated rotor rotatably supported in an outer frame. The rotor is only rotatable about its axis. A moving unit is slidably disposed within the rotor. The moving unit has an upper piston and is axially movable upon application of pneumatic pressure to the upper piston. The moving unit is also rotatable about its axis because of spline connection with the rotor. A valve is disposed for selectively applying the pneumatic pressure to the piston and to the rotor. Upon application of the pneumatic pressure, the moving unit is moved downwardly, and the pneumatic pressure is then introduced into the rotor for rotating the same. The rotation of the rotor is transmitted to the moving unit. The valve closes a fluid passage directing to the piston and to the rotor when the moving unit has the lowermost position.

Pneumatically operated screw driver

A combustion gas powered tool includes a member defining a part of cylindrical combustion chamber having an axis. A piston is movable in a direction along the axis of the combustion chamber. The piston defines the combustion chamber in conjunction with the member. A mixture of air and fuel is generated in the combustion chamber. The air-fuel mixture in the combustion chamber is burned to drive the piston. An orifice grille extends in the combustion chamber, and is parallel to the axis of the combustion chamber.

Combustion gas powered tool

A cutting apparatus comprising a swinging cutter unit which is pivotally coupled through a first shaft to a stationary working table so as to be swingable about the first shaft between its raised resting position and its lowered cutting position. The swinging cutter unit includes a motor-driven circular saw-blade fixedly mounted on a second shaft coupled to a drive motor, a housing for partially encasing an upper side portion of the circular saw-blade and supporting the second shaft so that the circular saw-blade is rotatable about the second shaft in response to operation of the drive motor, and a blade guard supported by the housing to be rotatable about the second shaft to expose and cover the saw-blade. The blade guard is biased by means of a spring so as to cover the saw-blade and has an engaging device at a portion of the outer surface thereof. An elongated arm is provided such that one end portion thereof is fixedly secured to a stationary portion of the cutting apparatus and the other end portion thereof is positioned near the engaging device. At the other end portion is provided a third shaft engaged with the engaging device so that the blade guard is rotated about the second shaft in response to a swinging movement of the cutter unit to expose the saw-blade when the cutter unit is moving to the cutting position and cover the portion thereof when moving to the resting position.

Guard-moving system in a cutting apparatus

Growing community of inventors

Katsuta, Japan

Yasuyuki Hirano