Abstract: A power tool that performs a predetermined operation by using a tool bit and has a grip part and a dust suction device. The dust suction device has a dust suction part that extends in an axial direction of the tool bit and sucks and collects dust generated during operation at a tip of the tool bit, and the dust suction part can be moved between a first position in which the dust suction part covers a bit tip of the tool bit and a second position in which the bit tip is exposed. The dust suction device further has an operation mode switching mechanism that is capable of switching between a first operation mode in which the dust suction part is allowed to move between the first and second positions and a second operation mode in which the dust suction part is locked in the second position, and the operation mode switching mechanism is provided in a region of the grip part or its vicinity such that it can be operated with a user's hand holding the grip part.

Abstract: In an upper surface of a crank housing is provided an inlet for grease which is configured to be openable and closable by a cap. A vibration damping mechanism, which includes a counterweight provided with a connecting pin loosely fitted in a connecting hole of an eccentric pin when the cap is attached, is mounted in the cap, whereby the vibration damping mechanism is allowed to be taken in and out of the crank housing through the inlet by attachment and detachment of the cap to and from the inlet.

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: An effective technique for detecting several load conditions different in presence or absence and magnitude of load applied to a tool bit is provided in a hand-held tool. A hand-held tool 101 performs a predetermined operation while pressing a tool bit 119 mounted in a front end region of a tool body 103 against a workpiece. A plurality of detecting sensors 161 of different kinds detect several load conditions different in presence or absence and magnitude of load applied to the tool bit 119. The hand-held tool 101 includes at least one of an indicating device 171 which indicates the load conditions based on a result detected by the detecting sensors 161, and a driving control device 135 which controls driving of the tool bit 119 based on the detected result.

Abstract: It is an object of the invention to provide a technique that contributes to rationalization of dust collection, in a dust collecting attachment for use on a power tool. Dust collecting attachments 250, 350 are used on a power tool 201 having a tool body 203, a tool bit 209 which can be coupled to a front end region of the tool body 203, and an auxiliary handle 208 attached to the tool body 203. The dust collecting attachments 250, 350 include dust collecting members 251, 351, respectively, which can be attached to the auxiliary handle 208 in such a manner as to surround the front end region of the tool body 203 around a longitudinal axis of the front end region in order to collect dust generated during operation by the power tool 201, and a connecting hose 273 for connecting the dust collecting members 251, 351 to a dust collector.

Abstract: A technique for allowing a user to operate an operating member disposed in a front end region of a power tool in the state in which a dust collecting attachment designed to be attached to the front end region of the power tool is left attached to the power tool. The dust collecting attachment is used on a power tool having an operating member for removal and/or bit angle setting of a tool bit coupled to a front end region of a tool body. The dust collecting attachment has a dust collecting member which can be attached to the front end region of the tool body. The dust collecting member has an opening formed in a region which faces the operating member in the state in which the dust collecting member is attached to the tool body, and the operating member can be operated by user's finger through the opening.

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 easily determine a currently-selected operation mode in a power tool which offers several operation modes. A representative electric hammer drill 101 embodying a power tool according to the invention has a controller 171 for at least controlling a driving motor 111. The controller 171 includes a switch detecting circuit 173 that detects the on or off state of each of first and second switches 141, 146 when power is on, a computing/driving section 174 that determines a current operation mode based on results of detection of the switch detecting circuit 173, and a motor control section 176 and a drive circuit 177 that output a drive control signal to the driving motor 111 when the switch in the off state is turned on after the computing/driving section 174 determines the operation mode.

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 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 an effective technique for enhancing the effect of reducing vibration of a grip of a reciprocating power tool. According to the present invention, a representative reciprocating power tool may comprise a tool bit, a tool body and a grip. The grip is connected to the tool body via an elastic element and a vibration damping part. The elastic element is resiliently disposed between the tool body and the grip and serves to absorb vibration transmitted from the tool body to the grip during operation. The vibration damping part is disposed between the tool body and the grip and serves to damp and/or attenuate the vibration. According to the invention, the spring constant of the elastic element can be made smaller due to vibration damping part.

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: 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 effective technique for enhancing the effect of reducing vibration of a grip of a reciprocating power tool. According to the present invention, a representative reciprocating power tool may comprise a tool bit, a tool body and a grip. The grip is connected to the tool body via an elastic element and a vibration damping part. The elastic element is resiliently disposed between the tool body and the grip and serves to absorb vibration transmitted from the tool body to the grip during operation. The vibration damping part is disposed between the tool body and the grip and serves to damp and/or attenuate the vibration. According to the invention, the spring constant of the elastic element can be made smaller due to vibration damping part.