Abstract: It is an object of the invention to provide a technique that contributes to realizing both the switch selecting function and the handle vibration-proofing function, in an impact tool which can switch an operation mode of a tool bit. An impact tool includes a motor 111, a tool body 103, a handle 109, a vibration-proofing cushioning material 161 which connects the tool body 103 and the handle 109 such that the tool body and the handle can move with respect to each other. The impact tool further includes a motor-driving manual operating member 143 disposed on the handle 109, an operation mode switching member 151 disposed on the tool body 101, and a movable member 153. When the operation mode switching member 151 is switched to first operation mode in which the tool bit 119 is continuously driven, the movable member 153 moves the manual operating member 143 from an off position to an on position and locks it in the on position.

Abstract: It is an object of the invention to provide an effective technique for reducing adverse effect of a dust suction device on the operability of a power tool, in the power tool which can suck dust generated during operation. The power tool has a motor 111 and a tool body 103 that houses the motor 111. A tool bit 119 is coupled to a tip end region of the tool body and driven by the motor 111 to perform a predetermined operation. The power tool further includes a dust suction part 151 through which dust generated during operation by the tool bit 119 is sucked and which covers at least a tip end of the tool bit 119, a dust transfer passage 153 through which the dust sucked into the dust suction part 151 is transferred and which is partly disposed within the tool body 103, and a dust discharge port 174 through which the dust transferred through the dust transfer passage 153 is discharged to the outside. Further, the dust discharge port 174 is disposed on the opposite side of the motor 111 from the tool bit 119.

Abstract: It is an object of the present invention to provide a technique for appropriately providing not only for normal rotation but for reverse rotation in a tightening tool having a clutch. Representative tightening tool according to the invention comprises a body, a driving motor housed in the body, a driving-side clutch element, an auxiliary clutch element, a driven-side clutch element, a driven shaft and a tool bit. During normal rotation of the driving motor, the driven-side clutch element is caused to move in the axial direction by application of a pressing force of the user to the body to engage with the driving-side clutch element. During reverse rotation of the driving motor, the driving-side clutch element and the auxiliary clutch element are caused to move relatively with respect to each other in the axial direction by rotating torque of the driving-side clutch element and the driving-side clutch element or the auxiliary clutch element engages with the driven-side clutch element.

Abstract: It is an object of the invention to provide an improvement in ease of operation of a driving mode switching mechanism in a hammer drill. According to the invention, a representative hammer drill includes a driving mode switching mechanism which has an operating part, a first switching member and a second switching member. The operating part can be turned to at least three rotating positions in its circumferential direction, while the operating part can be turned 360° on the rotation axis in the both directions. Thus, the user can select the desired driving mode in the shortest turning distance without passing though an unnecessary driving mode position. Therefore, ease of operation in mode change can be enhanced.

Abstract: It is an object of the invention to provide a technique which contributes to reduced size of a vibration-proof handle for a hand-held power tool. A representative hand-held power tool includes a power tool body 103 having a tip end region to which a tool bit 119 can be coupled, and a handle 109 arranged on the rear of the power tool body 103 on the side opposite to the tool bit 119 and designed to be held by a user. The handle 109 is connected to the power tool body 103 via elastic elements 181, 183 and can slide with respect to the power tool body 103 in an axial direction of the tool bit 119. The power tool body 103 has an extending region 105b that extends to a lower region of the handle 109 and receives the sliding movement of the handle 109.

Abstract: It is an object of the invention to provide a power tool having a rational structure. A representative power tool is provided to have a tool bit a power tool body, a motion converting mechanism housing chamber, a motion converting mechanism and a clutch mechanism. The power tool further includes a switching member, an opening, a rotating member, a switching operation transmitting mechanism and an actuating member. The switching member is disposed on an upper surface of the power tool body and can be manually operated by a user. The opening is provided to connect the motion converting mechanism housing chamber and the outside. The rotating member can rotate while closing the opening. The switching operation transmitting mechanism is disposed outside the motion converting mechanism housing chamber to connect the switching member to the rotating member and to transmit the switching operation effected by the user's manual operation of the switching member to the rotating member.

Abstract: It is an object of the invention to provide an improvement in ease of operation of a driving mode switching mechanism in a hammer drill. According to the invention, a representative hammer drill includes a driving mode switching mechanism which has an operating part, a first switching member and a second switching member. The operating part can be turned to at least three rotating positions in its circumferential direction, while the operating part can be turned 360° on the rotation axis in the both directions. Thus, the user can select the desired driving mode in the shortest turning distance without passing through an unnecessary driving mode position. Therefore, ease of operation in mode change can be enhanced.

Abstract: Connection of a bit with two balls is enabled while high operability of attachment and detachment of the bit is maintained. A pressing ring 23 is held at the advance position together with an operation sleeve 22 by a guide washer 24 forced by a coil spring 25. When the rear end of the bit is inserted into a tool holder 8, the balls 27, 27 that are rolled rearward by the contact of the rear end of the bit are pushed in between the pressing ring 23 and the guide washer 24 in order, and the balls 27, 27 can be retracted from the tool holder 8 in the state where the pressing ring 23 is held at the advance position by the tilt of the guide washer 24.

Abstract: It is an object of the present invention to provide an effective technique to improve ease of operation of the power impact tool. The power tool of the present invention includes a tool body, a tool bit, a motor, first and second switches and a mode changing mechanism. The motor is driven only when both switches are in an on position. The first switch is biased in the off position. The second switch is biased in the last position operated. The mode changing mechanism switches between hammer operation modes such that in the first hammer mode, the user actuates the first switch while the second switch is locked in the on position and in the second hammer mode, the first switch is locked in the on position while the second switch is actuated. In the second hammer mode, actuating the second switch similar to a toggle switch operates the tool.

Abstract: It is an object of the invention to provide a technique in a power tool having a detachable bit holder for preventing a bit holder from being detached from the tool body even if unexpected external force is exerted on an operating member for lock release. A representative power tool includes a tool body, a single holder mounting portion. The holder mounting portion removably holds a bit holder selected from multiple kinds of bit holders for holding multiple kinds of tool bits in different manners. Each bit holder includes a cylindrical portion, a through hole formed through the cylindrical portion, an engaging member disposed within the through hole, a cylindrical operating member axially movably fitted on the cylindrical portion between a movement prevented position and a movement allowed position.

Abstract: A combustion power tool having a first combustion chamber, a second combustion chamber, an igniter, a partition, and a driving mechanism. Flammable gas is introduced or charged into the first and second combustion chamber. The igniter is disposed in the first combustion chamber. The partition separates the first combustion chamber from the second combustion chamber. Communication holes are formed in the partition at different angles with respect to the longitudinal direction of the first combustion chamber. The communication holes communicate the first combustion chamber with the second combustion chamber. The driving mechanism performs a predetermined processing work by utilizing an explosive combustion pressure.

Abstract: It is an object of the invention to provide a power tool having a rational structure. A representative power tool is provided to have a tool bit a power tool body, a motion converting mechanism housing chamber, a motion converting mechanism and a clutch mechanism. The power tool further includes a switching member, an opening, a rotating member, a switching operation transmitting mechanism and an actuating member. The switching member is disposed on an upper surface of the power tool body and can be manually operated by a user. The opening is provided to connect the motion converting mechanism housing chamber and the outside. The rotating member can rotate while closing the opening. The switching operation transmitting mechanism is disposed outside the motion converting mechanism housing chamber to connect the switching member to the rotating member and to transmit the switching operation effected by the user's manual operation of the switching member to the rotating member.

Abstract: It is an object of the present invention to provide a technique for appropriately providing not only for normal rotation but for reverse rotation in a tightening tool having a clutch. Representative tightening tool according to the invention comprises a body, a driving motor housed in the body, a driving-side clutch element, an auxiliary clutch element, a driven-side clutch element, a driven shaft and a tool bit. During normal rotation of the driving motor, the driven-side clutch element is caused to move in the axial direction by application of a pressing force of the user to the body to engage with the driving-side clutch element. During reverse rotation of the driving motor, the driving-side clutch element and the auxiliary clutch element are caused to move relatively with respect to each other in the axial direction by rotating torque of the driving-side clutch element and the driving-side clutch element or the auxiliary clutch element engages with the driven-side clutch element.

Abstract: Accordingly, it is an object of the present invention to provide an effective technique to improve ease of operation of the power impact tool. The representative power impact tool according to the present invention includes a tool body, a tool bit, a motor, first and second switches and a mode changing mechanism. The tool bit performs a striking movement. The motor is driven only when both of the switches are turned on. The first switch is urged from the on position side to the off position side and normally held in the off position. The second switch is turned between the on position and the off position and held in one of the on and off positions unless operated to be turned to the opposite position. The mode changing mechanism switches between hammer operation modes of the tool bit. According to the first hammer mode, the user is allowed to actuate the first switch while the second switch is locked in the on position.

Abstract: A hammer drill (1) includes a lock plate (35) forward of a boss sleeve (13) and a swash bearing (14) which cooperates with the boss sleeve to convert the rotation of an intermediate shaft (5) on which the boss sleeve is mounted. The lock plate is mounted on the boss sleeve and selectively engages claws (23) of the boss sleeve (13) in a manner that permits its integral rotation with and axial slide with respect to the boss sleeve. The lock plate is additionally biased in the forward direction by a coil spring (38) so that when a clutch (19) is shifted forward in a drill mode, the lock plate also moves forward into engagement with a stopper (39) secured to an inner housing (4), preventing inadvertent rotation of the boss sleeve.

Abstract: A combustion power tool having a first combustion chamber, a second combustion chamber, an igniter, a partition, and a driving mechanism. Flammable gas is introduced or charged into the first and second combustion chamber. The igniter is disposed in the first combustion chamber. The partition separates the first combustion chamber from the second combustion chamber. Communication holes are formed in the partition at different angles with respect to the longitudinal direction of the first combustion chamber. The communication holes communicate the first combustion chamber with the second combustion chamber. The driving mechanism performs a predetermined processing work by utilizing an explosive combustion pressure.

Abstract: A hammer drill (1) includes a lock plate (35) forward of a boss sleeve (13) and a swash bearing (14) which cooperates with the boss sleeve to convert the rotation of an intermediate shaft (5) on which the boss sleeve is mounted. The lock plate is mounted on the boss sleeve and selectively engages claws (23) of the boss sleeve (13) in a manner that permits its integral rotation with and axial slide with respect to the boss sleeve. The lock plate is additionally biased in the forward direction by a coil spring (38) so that when a clutch (19) is shifted forward in a drill mode, the lock plate also moves forward into engagement with a stopper (39) secured to an inner housing (4), preventing inadvertent rotation of the boss sleeve.