Hitachi Koki Co., Ltd.

Koki Holdings Co., Ltd.

Hitachi Koko Co., Ltd.

Isamu Tanji

Akira Uno

Yoshihiro Nakano

Yoshimitsu Iijima

Yoshinori Ishizawa

Yasuki Ohmori

Yasunori Ogawa

Hideyuki Hashimoto

Kaoru Ichikawa

Sueji Tachihara

Yasuyuki Hirano

Satoshi Kuno

The durability of the driver is further improved. The nail driver for driving a nail into a material to be driven includes: a plunger moved in a first direction parallel to a driving direction of the nail by bias caused by a coil spring and moved in a second direction opposite to the first direction against the bias of the coil spring (); and a weight moved in the second direction by bias caused by a coil spring and moved in the first direction against the bias of the coil spring. The weight () is moved in the second direction when the plunger is moved in the first direction and is moved in the first direction when the plunger is moved in the second direction, and the plunger and the weight are moved in the first direction and the second direction so as to be independent from each other.

Driver

A nail driving machine capable of reducing vibrations is provided. A nail driving machine that strikes a nail to be driven into a workpiece W includes a driver blade that is provided to be capable of moving along an axis and moves in a first direction to strike the nail, a weight that when the driver blade strikes the nail, moves in a second direction reverse to the first direction, and a coil spring that is compressed along the axis to generate a repulsive force before the driver blade strikes the nail and causes the driver blade to move in the first direction to strike the nail due to the repulsive force and causes the weight to move in the second direction due to the repulsive force.

Fastener driving tool

A driver includes a housing in which an accumulator for accumulating compressed air is provided; a trigger provided in the housing; a cylinder stored in the housing; a piston stored to be slidable in the cylinder and driven by the compressed air; and a head valve moving in response to movement of the trigger between an acting position which is distant from the cylinder so that the compressed air acts on the piston and a blocking position which abuts against the cylinder so that the action of the compressed air on the piston is blocked. The cylinder can be arranged at a first position and a second position closer to the head valve than the first position in a state that the head valve moves from the blocking position to the acting position.

Pneumatic nail driver

A fastening machineis provided, which prevents the tip memberfrom wear and improve its durability as well as align a material into which a fastener is to be driven. The fastening machineis provided with a housing, a handleA extended from the housing, a noseextended from the housingand comprising an ejecting mouthto fire a fastenerand a tip memberarranged at the tip of nosein the direction of ejecting the fastener. The tip memberis characterized by comprising a super-hard material memberin the side facing a material into which a fastener is to be driven and in the side opposite to the direction of extending the handleA.

Fastening machine

The present application relates to a driving machine. The driving machine has a driver blade for striking a fastener and a nose portion having formed therein an injection passage which slidably guides the driver blade, and into which the fastener is fed to be injected therefrom. An injection hole from which the fastener is injected is specified at a leading end in an injecting direction of the injection passage. The injection hole is defined by a first guide portion and a second guide portion which is movable relative to the first guide portion so as to change a cross section, perpendicular to the injecting direction, of the injection hole. A positioning apparatus is provided to dispose the second guide portion at a plurality of positions relative to the first guide portion.

Driving machine

A driving machine including: a driver blade for striking a fastener; and a nose portion having formed therein an injection passage which slidably guides the driver blade, and into which the fastener is fed to be injected therefrom, wherein an injection hole from which the fastener is injected is specified at a leading end in an injecting direction of the injection passage, wherein the injection hole being defined by a first guide portion and a second guide portion which is movable relative to the first guide portion so as to change a cross section, perpendicular to the injecting direction, of the injection hole, and wherein a positioning apparatus is provided to dispose the second guide portion at a plurality of positions relative to the first guide portion.

A center portion of a handle housing portionis arranged with a pressure reducing valve mechanism portionfor reducing a pressure of high pressure compressed air to be surrounded by an exhaust chamberin a state of making a triggerON, air pressure Pof a secondary pressure side portof the pressure reducing valve mechanism portionis made to be higher than air pressure Pof a secondary pressure side portof the pressure reducing valve mechanism portionin a state of making the triggerOFF by communicating a hermetically closed chamberof a pressure control springand the exhaust chamberby way of a relief holesuch that an exhaust air pressure of an air motor mechanism portionis added to a spring force F of the pressure control springof the pressure reducing valve mechanism portion

Air tool

A nail gun having a contact arm normally biased in a direction away from a workpiece by compression springs. A free end of the contact arm is brought into abutment with a workpiece and a trigger is pulled for driving a nail thereinto. In the trigger pulling operation, an inner end of the contact arm is engaged with a trigger arm which is biased by a plunger spring through a plunger. Because the contact arm is held on the workpiece, the plunger is moved to provide ON state against biasing force of the plunger spring. Immediately after the nail driving, a nail gun body is moved in a direction away from the workpiece relative to the contact arm. This causes disengagement of the trigger arm from the inner end, to relatively move the nail gun body toward the workpiece by the biasing force of the compression springs. This means relative movement of the contact arm in the direction away from the workpiece. If the trigger is released, the trigger arm is again brought into engagement with the inner end, because the trigger arm is normally urged toward the inner end by a trigger arm spring.

Fastener driving tool having contact arm in contact with workpiece

An air motor is provided in a housing and driven by the compression air introduced from an intake port. An anvil, receiving the rotational force of the air motor, has a rear end accommodated in the housing and a front end protruding out of the housing. A driver bit, engaged with a screw inserted into a board member, is rotatable and shiftable together with the anvil relative to the housing. An intake valve is responsive to a retractile shift movement of the driver bit to open an air passage connecting the intake port to the air motor. The intake valve closes this air passage in response to a protrusile shift movement of the driver bit returning to its original position so as to stop the air motor. An assist means is provided for applying the pressure of the compression air to a rear end surface of the anvil in response to the rotation of the air motor.

Pneumatically operable screw driver

A pneumatically operated screw driver includes a mechanism for assisting separation of screw from a screw band. The band is made of a deformable material to which a plurality of screws are detachably held. The band has one side where a head of the screw is exposed, and has another side from which a threaded portion of the screw extends. The screw driver includes a housing, a slide member, a pneumatic motor and a drive bit driven by the pneumatic motor and movable in an axial direction thereof and rotatable about the axis. The slide member is slidable in the axial direction, and is formed with a screw passage. The other side of the screw band is pressed onto a wall of the slide member. Shearing deformation occurs in the screw band when the drive bit presses the head of the screw while the other side of the screw band is held by the wall, thereby separating the screw from the screw band. A sub-piston cylinder is provided beside the housing and, a sub-piston connected to the slide member is disposed in the cylinder. A compressed air is introduced into a sub-piston chamber from the pneumatic motor to move the sub-piston, thereby moving the slide member at a phase of separation of the screw from the screw band.

Pneumatically operated screw driver having mechanism for assisting

A percussion tool comprises a cylinder 3 communicated to a pressure accumulating chamber 16 storing pressurized air therein, and a piston 4 slidable in the cylinder 3 when pressurized air is introduced into the cylinder 3 from the pressure accumulating chamber 16 and pressure of the introduced air is applied on the piston 4. A circular groove 6 is recessed on a peripheral surface of the piston 4, the peripheral surface adjacently facing to an inside wall of the cylinder 3. A piston ring 10 is accommodated in the circular groove 6, so as to provide a hermetical sealing between the piston 4 and the cylinder 3. And, a ring bumper 11 made of resilient member is provided in the circular groove 6 adjacent to the piston ring 10 in a sliding direction of the piston 4.

Piston arrangement for a percussion tool

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 pneumatic fastener driving tool includes a main valve operable to cause compressed air to be alternately introduced into and discharged from the upper piston chamber, a first passage leading the compressed air into the main valve chamber, a repeat valve disposed in the first passage for opening and closing the same, and a second passage extending between the lower piston chamber and a repeat valve chamber in which the repeat valve is reciprocably received. With this construction, the repeat valve is reciprocally movable in response to a change of pressure in the lower piston chamber to cause the main valve to reciprocate, thereby reciprocating the piston repeatedly. Since the reciprocating fastener driving movement of the piston is directly related to the reciprocating movement of the repeat valve, the fastener driving work can be achieved reliably without causing any operational failure such as a non-load striking.

Pneumatic fastener driving tool

A pneumatic fastener driving tool having an elastic cap means for changing compressed air exhausting direction. The cap means has a circular disc shaped top wall and a skirt portion extending from an outer peripheral end portion of the top wall. The skirt portion has a lower portion integrally provided with an annular projection extending radially inwardly. The cap means is elastically deformable and engageable with a casing positioned above a main body portion in which a drive piston is reciprocally disposed. The casing is formed with an annular groove with which the annular projection is engageable. The casing is formed with a fluid passage to allow compressed air in the main body portion to be discharged therethrough to an atmosphere. The cap means is also formed with an exhaust opening in communication with the fluid passage. Upon manual rotation of the cap member against a frictional force given by the engagement between the projection and the groove, an angular position of the exhaust port can be changed.

Growing community of inventors

Ibaraki, Japan

Isamu Tanji