Abstract: The nailing machine (1) comprises an air passage (510) allowing communication between a cylinder (200) and a return air chamber (500) in which compressed air for returning a piston (300) to the initial position is accumulated. The air passage (510) is provided with a control valve (520) controlling entry of compressed air into the return air chamber (500) from the cylinder (200). The control valve (520) opens the air passage (510) and allows entry of compressed air into the return air chamber (500) in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body (100) relative to the push lever (700) is smaller than a predetermined distance. The compressed air that has entered the return air chamber (500) further enters a below-the-piston chamber and serves as air damper, reducing the driving force.

Abstract: A fastener driving tool is capable of not only linearly driving but also rotationally fastening a fastener into a workpiece P. The fastener driving tool includes a housing 2, a nose portion 40 formed with an injection passage 40a through which a fastener 41 is driven, a magazine 4 accommodating fasteners 41 and supplying a fastener 41 to the nose portion 40, a push lever 5 movable relative to the housing 2 upon depression against the workpiece P, combustion chamber frames 12, 22 movable in the housing 2 in accordance with the movement of the push lever 5, and first and second cylinders 7, 8 fixed to the housing 2. First and second pistons 71, 81 are movably disposed in the first and second cylinders 7,8, respectively, and a bit 9 extends from the first piston 71. A rod 14 formed with a rack 14A extends from the second piston 72. The rack 14A is engageable with a motion conversion mechanism 6 for converting a linear motion of the rod 14 into rotational motion of the bit 9.

Abstract: The fastening tool includes a housing, a trigger, a cylinder, a piston, and a main valve. The main valve allows a communication between the cylinder and the first air chamber in conjunction with an operation of the trigger. The housing is formed with a first air chamber, a second air chamber, and a third air chamber. The second air chamber is communicated with the cylinder in conjunction with a movement of the piston. The third air chamber accumulates or discharges the compressed air in the first air chamber in conjunction with the operation of the trigger. The cylinder is movable between a first position where the cylinder upper chamber being in communication with the first air chamber, and a second position where the cylinder upper chamber being blocked from the first air chamber based on a differential pressure between the second air chamber and the third air chamber.

Abstract: A screw driving machine includes a bit that is movable to strike a screw against a workpiece and rotatable to rotate the screw to the workpiece, a combustion-type power mechanism including a spark plug that ignites combustible gas filled in a combustion chamber to apply striking force to cause the bit to strike the screw, a motor that generates a rotative force when supplied with electric force, and a power transmission mechanism that transmits the rotative force generated at the motor to the bit to cause the bit to rotate.

Abstract: The nailing machine (1) comprises an air passage (510) allowing communication between a cylinder (200) and a return air chamber (500) in which compressed air for returning a piston (300) to the initial position is accumulated. The air passage (510) is provided with a control valve (520) controlling entry of compressed air into the return air chamber (500) from the cylinder (200). The control valve (520) opens the air passage 510 and allows entry of compressed air into the return air chamber (500) in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body (100) relative to the push lever (700) is smaller than a predetermined distance. The compressed air that has entered the return air chamber (500) further enters a below-the-piston chamber and serves as air damper, reducing excess energy absorbed by a piston bumper (360).

Abstract: A fastener driving tool is capable of not only linearly driving but also rotationally fastening a fastener into a workpiece P. The fastener driving tool includes a housing 2, a nose portion 40 formed with an injection passage 40a through which a fastener 41 is driven, a magazine 4 accommodating fasteners 41 and supplying a fastener 41 to the nose portion 40, a push lever 5 movable relative to the housing 2 upon depression against the workpiece P, combustion chamber frames 12, 22 movable in the housing 2 in accordance with the movement of the push lever 5, and first and second cylinders 7, 8 fixed to the housing 2. First and second pistons 71, 81 are movably disposed in the first and second cylinders 7,8, respectively, and a bit 9 extends from the first piston 71. A rod 14 formed with a rack 14A extends from the second piston 72. The rack 14A is engageable with a motion conversion mechanism 6 for converting a linear motion of the rod 14 into rotational motion of the bit 9.

Abstract: An oil pulse tool including: a brushless motor which includes stator windings; a drive circuit configured to apply a driving voltage to any of the stator windings of the brushless motor at a predetermined timing; an oil pulse mechanism portion configured to be rotary driven by the brushless motor; and an output shaft which is connected to the oil pulse mechanism portion, wherein the drive circuit changes an advance angle of the driving voltage in accordance with a rotational position of the oil pulse mechanism portion.

Abstract: The nailing machine (1) comprises an air passage (510) allowing communication between a cylinder (200) and a return air chamber (500) in which compressed air for returning a piston (300) to the initial position is accumulated. The air passage (510) is provided with a control valve (520) controlling entry of compressed air into the return air chamber (500) from the cylinder (200). The control valve (520) opens the air passage (510) and allows entry of compressed air into the return air chamber (500) in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body (100) relative to the push lever (700) is smaller than a predetermined distance. The compressed air that has entered the return air chamber (500) further enters a below-the-piston chamber and serves as air damper, reducing the driving force.

Abstract: The nailing machine (1) comprises an air passage (510) allowing communication between a cylinder (200) and a return air chamber (500) in which compressed air for returning a piston (300) to the initial position is accumulated. The air passage (510) is provided with a control valve (520) controlling entry of compressed air into the return air chamber (500) from the cylinder (200). The control valve (520) opens the air passage 510 and allows entry of compressed air into the return air chamber (500) in the case wherein the nailed object produces a small reaction force upon driving the nail, namely when the upward moving distance of the body (100) relative to the push lever (700) is smaller than a predetermined distance. The compressed air that has entered the return air chamber (500) further enters a below-the-piston chamber and serves as air damper, reducing excess energy absorbed by a piston bumper (360).

Abstract: A screw driving machine includes a bit that is movable to strike a screw against a workpiece and rotatable to rotate the screw to the workpiece, a combustion-type power mechanism including a spark plug that ignites combustible gas filled in a combustion chamber to apply striking force to cause the bit to strike the screw, a motor that generates a rotative force when supplied with electric force, and a power transmission mechanism that transmits the rotative force generated at the motor to the bit to cause the bit to rotate.

Abstract: A pneumatically operated power tool includes an outer frame, a driving components, a pressure reduction valve, and a switching valve. The outer frame has a compressed air intake portion and defines therein a compressed air chamber. The driving components are disposed in the outer frame and are driven by a compressed air in the compressed air chamber. The pressure reduction valve defines a pressure receiving space and allows a compressed air to flow from the air intake portion to the compressed air chamber and to the pressure receiving space. The switching valve is movable between a first position where the compressed air flows from the compressed air intake portion to the pressure receiving space, and a second position where a communication between the compressed air intake portion and the pressure receiving space is blocked.

Abstract: A pneumatically operated power tool includes an outer frame, a driving components, a pressure reduction valve, and a switching valve. The outer frame has a compressed air intake portion and defines therein a compressed air chamber. The driving components are disposed in the outer frame and are driven by a compressed air in the compressed air chamber. The pressure reduction valve defines a pressure receiving space and allows a compressed air to flow from the air intake portion to the compressed air chamber and to the pressure receiving space. The switching valve is movable between a first position where the compressed air flows from the compressed air intake portion to the pressure receiving space, and a second position where a communication between the compressed air intake portion and the pressure receiving space is blocked.

Abstract: An acoustic signal processing circuit extracts input speech pattern data and subsidiary feature data from an input speech signal. The input speech pattern data comprise frequency spectra, whereas the subsidiary feature data comprise phoneme and acoustic features. These data are then stored in a data buffer memory. The similarity measures between the input speech pattern data stored in the data buffer memory and reference speech pattern data stored in a dictionary memory are computed by a similarity computation circuit. When the largest similarity measure exceeds a first threshold value and when the difference between the largest similarity measure and the second largest measure exceeds a second threshold value, category data of the reference pattern which gives the largest similarity measure is produced by a control circuit to correspond to an input speech.