Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Haruhiko Oouchi

Michio Wakabayashi

Yasuo Sasaki

Takeshi Kamo

Yoshinori Ishizawa

Shoichi Hirai

Masato Sakai

Akira Uno

Yoshimitsu Iijima

A driving tool capable of avoiding blank shot after a predetermined time has elapsed when performing a bump firing and capable of smoothly performing the bump firing is provided. The driving tool includes: an accumulator chamber which accumulates compressed air; a nose section provided on a housing; a cylinder; a trigger; and a push lever provided in the nose section, and when the trigger and the push lever are operated, the compressed air is supplied into the cylinder. The driving tool further includes: a delay valve which prevents the compressed air from being supplied into the cylinder when the push lever is not operated within a predetermined time after the trigger is operated: and a switching valve which supplies the compressed air of the accumulator chamber to the delay valve when the trigger is operated, and discharges the compressed air supplied to the delay valve to an outside of the housing when the push lever is operated within the predetermined time.

Driving tool

In a driving tool, a push lever plunger is moved upward by a push lever unit when the push lever unit is disposed at an uppermost position. The push lever unit includes a first protruding part and a second protruding part. The first protruding part is configured to contact a first contact part of a housing when the push lever unit is disposed at the uppermost position. The second protruding part is configured to contact a second contact part of the housing when the push lever unit is disposed at the uppermost position. A compressed air control unit, the second protruding part, and an ejection channel are disposed within an imaginary plane extending in an approximate vertical direction. The compressed air control unit is disposed on a side opposite to the second protruding part with respect to the ejection channel in a horizontal direction.

Driving tool with push lever configured to contact housing

A rigid member is configured to move a valve member to separate the valve member from an engaging part when a push lever moves from a lower dead center to an upper dead center. A resilient member is configured to move the valve member to separate the valve member from the engaging part when the push lever moves from the lower dead center to the upper dead center. A switching part selects one of the rigid member and the resilient member to move the valve member to separate the valve member from the engaging part. When the switching part selects the rigid member, a fastener driving operation is performed regardless of an order of a pulling operation and a pressing operation. When the switching part selects the resilient member, the fastener driving operation is performed only when the pulling operation is executed after the pressing operation is executed.

Fastener driving tool

A driving tool includes a housing, a magazine, a cylinder head, a push lever, a cylinder, a combustion chamber frame, a piston, an injection part, and a fastener feeding unit. The housing has one end portion and another end portion. The magazine is connected to the housing and accommodating a fastener. The cylinder head is disposed at the one end portion. The push lever is movable relative to the housing upon pressure contacting a workpiece in a moving direction. The cylinder is fixed to the housing. The combustion chamber frame is movable in the housing in accordance with the push lever and selectively defining a combustion chamber in cooperation with the cylinder. The piston is slidably reciprocally movable relative to the cylinder and displaced upon expansion of air/fuel mixture in the combustion chamber. The injection part is connected to the another end portion of the housing and having an injection passage in communication with the magazine. The fastener feeding unit feeding the fastener to the injection passage in accordance with the movement of the push lever. The push lever includes a first guiding part configured to be slidably engaged with the fastener feeding unit. The fastener feeding unit is movable between an initial position and a feed position positioned downstream of the initial position in a feeding direction in which the fastener is fed. The fastener feeding unit slidably moves from the initial position to the feeding position with respect to the first guiding part for feeding the fastener downstream in the feeding direction in accordance with the movement of the push lever upon pressing the workpiece.

A pneumatically operated screw driver ensuring a complete return of a piston to its top dead center. The screw driver has a compressed air return chamber for returning the piston to its top dead center by applying a compressed air in the return chamber to the piston. The piston includes a main piston and an auxiliary piston. The main piston is first reaches its bottom dead center, and then the auxiliary piston reaches its bottom dead center whereupon screw driving is terminated. Before the auxiliary piston reaches its bottom dead center, and after the main piston moves past a predetermined position, a compressed air is introduced into the return chamber. After the main piston reaches the bottom dead center, application of the compressed air pressure in the return chamber to the auxiliary piston is prevented.

Pneumatically operated screw driver

A pneumatically operated power tool such as a screw driver, a nail gun and an impact wrench those being driven by a pneumatic pressure. A pressure reduction valve is provided between a connector connected to a compressor and a compressed air chamber defined in an outer frame of the power tool for supplying a pressure lower than the pressure at the connector to the compressed air chamber. A passage section is provided independently of the pressure reduction valve and communicating the connector with the compressed air chamber. A valve member is disposed at the passage section for selectively applying compressed air from the connector to the compressed air chamber directly through the passage section.

Pneumatically operated power tool having mechanism for changing compressed air pressure

A pneumatically operated screw driver ensuring a complete return of a piston to its top dead center. The screw driver has a compressed air return chamber for returning the piston to its top dead center by applying a compressed air in the return chamber to the piston. The piston includes a main piston and an auxiliary piston. The auxiliary piston includes a piston section and a flange section those being disposed in the main piston. The piston section is slidably movable relative to the main piston, and the flange section is axially spaced away from the piston section and radially spaced away from the main piston. After the main piston reaches its bottom dead center, the auxiliary piston further moves toward its bottom dead center. An air space chamber is provided between the piston section and the flange section and within the main piston.

Portable gas nailing machine

A compact and light-weight pneumatically operated screw driver providing high speed screw fastening with high operability. A rotary member rotationally driven by a pneumatic motor includes a main rotary member made from a plastic material and a sliding segment fixed to the main rotary member. A rotation slide member is axially slidably movable relative to the rotary member and is rotatable together with the rotation of the rotary member. A shut-off section is provided on which the rotation slide member is rotationally seated when the rotation slide member is moved toward the shut-off section. The rotation slide member is made from an elastic material. A sleeve like piston having a seal ring in sliding contact with a cylinder is provided. The seal ring shuts off a supply of compressed air to the pneumatic motor only by the seating of the rotation slide member onto the shut-off section.

Growing community of inventors

Hitachinaka, Japan

Haruhiko Oouchi