Abstract: In a dust collection device that collects dust particles that an impact tool generates, disclosed is a feature that can accommodate the lengths of tool bits that are mounted to the impact tool when a machining operation is executed by exchanging tool bits of different lengths. The dust collection device collects dust that the impact tool generates and is attached to said impact tool that, in the lengthwise direction, linearly operates the tool bit mounted to the end region of a tool body. The dust collection device has a dust intake port that sucks dust, and said dust intake port can be repositioned in the lengthwise direction of the tool bit in accordance with the length in the lengthwise direction of said tool bit.

Abstract: Disclosed is a feature that collects dust particles that arise from a processing operation of an impact tool. The dust collection device collects dust that arises from of a processing operation and is attached to the impact tool that performs a pre-determined processing operation on a processed member by way of a tool bit mounted to the tip region of the tool body being linearly operated at least in the lengthwise direction. The dust collection device has a dust collection unit of which the tip opens as a dust intake port and the contour shape is formed unevenly around the long axis of the tool bit. The position of the dust collection unit is freely selected around the long axis of the tool bit, and it is possible to cause the position to change around the long axis of the bit.

Abstract: A dust collection device, that collects dust particles generated by an impact tool, has a feature that enables the attachment of the device to the impact tool, which is not provided with an attachment section for the device. The dust collection device has a tool body and an auxiliary handle, attached removably to the tool body, and is attached to an electric hammer that, in the lengthwise direction, linearly operates a tool bit mounted to the tip region of the tool body, and collects dust generated by the electric hammer. The dust collection device has: a dust collection unit that has a dust intake port at the tip; a dust collection hose, connected to the dust collection unit, for transferring dust to the downstream side; and a hose-holding unit that holds the dust collection hose. The hose-holding unit can be attached to and removed from the auxiliary handle.

Abstract: It is an object of the invention to provide a technique that contributes to rationalization of a mechanism relating to reduction of vibration in an impact tool. Representative impact tool includes a tool body, a hammer actuating member, a dynamic vibration reducer and a positioning elastic element. The positioning elastic element contacts the hammer actuating member and thereby positions the tool body with respect to the workpiece so as to absorb a reaction force caused by rebound from the workpiece and acts on the hammer actuating member when the hammer actuating member performs the hammering operation on the workpiece. The positioning elastic element includes the elastic element formed as a component part of the dynamic vibration reducer.

Abstract: A feature that contributes to an improvement in the attachment to an impact tool of a dust collection device that is attached to the impact tool and that collects dust particles that said impact tool generates. The dust collection device collects dust that the impact tool generates and is attached to said impact tool that, in the lengthwise direction, linearly operates a tool bit that is mounted to the tip region of a tool body. The dust collection device has: a dust collection unit that has a dust intake port at the tip; and a dust transfer unit that is connected with the dust collection unit in order to transfer dust sucked in from the dust intake port towards the downstream side. The dust collection unit is held by the shaft section of the tool bit, and the dust transfer unit is held by the tool body.

Abstract: It is an object of the invention to reduce noise caused by run-out of a tool bit in an impact tool. The representative impact tool according to the invention includes a tool holder 137 that houses a tool bit 119 in such a manner that the tool bit can linearly move in its axial direction, and a barrel 108 that is integrally connected to the tool holder 137 The impact tool further includes an elastic element 155 that is disposed between an inner circumferential surface of the tool holder 137 and an outer circumferential surface of the tool bit 119 in an end region of the tool bit 119 on the barrel side and connected in close contact with the tool holder 137 and the tool bit 119 over a predetermined length of the tool bit 119 in the axial direction. The elastic element 155 applies a biasing force to prevent a run-out of the tool bit 119 in a direction transverse to the axial direction. Further, an intermediate element 145 comes in point contact with the tool bit 119 on its axial center line.

Abstract: A grinder as a power tool has a torque limiter. The torque limiter includes a second bevel gear; a spindle; a flange to which the rotation of the second bevel gear is transmitted, and a plurality of balls which are disposed between the second bevel gear and the flange. The ball is positioned at a first region and the second bevel gear, the ball and the flange rotate integrally thereby the rotation is transmitted to the flange. In a state that a torque exerted on the spindle exceeding the predetermined threshold, a relative rotation between the second bevel gear and the flange is occurred and the ball moves from the first region to the second region while rolling by means of the relative rotation. Therefore, the transmission of the rotation from the second bevel gear to the flange is regulated, and the torque exerted on the spindle is regulated.

Abstract: A power tool, which actuates a tool linearly in a longitudinal direction of the tool, the power tool performs a predetermined operation to a workpiece, having: a drive mechanism which actuates the tool; a rotational shaft which actuates the drive mechanism; a swing lever which swings along the longitudinal direction by a rotational motion of the rotational shaft; and a dynamic vibration reducer which alleviates vibration generated during the predetermined operation. The dynamic vibration reducer includes a weight which is linearly movable in the longitudinal direction an elastic member which biases the weight. The weight is adapted to be actuated mechanically and forcibly by a motion component with respect to the longitudinal direction of a swinging motion of the swing lever in a state that the weight is biased by the elastic member.

Abstract: It is an object of the invention to reduce noise caused by run-out of a tool bit in an impact tool. The representative impact tool according to the invention includes a tool holder 137 that houses a tool bit 119 in such a manner that the tool bit can linearly move in its axial direction, and a barrel 108 that is integrally connected to the tool holder 137 The impact tool further includes an elastic element 155 that is disposed between an inner circumferential surface of the tool holder 137 and an outer circumferential surface of the tool bit 119 in an end region of the tool bit 119 on the barrel side and connected in close contact with the tool holder 137 and the tool bit 119 over a predetermined length of the tool bit 119 in the axial direction. The elastic element 155 applies a biasing force to prevent a run-out of the tool bit 119 in a direction transverse to the axial direction. Further, an intermediate element 145 comes in point contact with the tool bit 119 on its axial center line.

Abstract: An impact absorbing mechanism for absorbing impact generated upon meshing of gears by starting or stopping an electric motor, for example, in a speed reduction gear train of a disk grinder, has the problem that its ease of manufacture and the durability are lowered because small elastic components are located between a driven gear and a driven shaft when an impact absorbing action occurs in the rotational direction in the related art. The present invention is aimed to improve the ease of manufacture and the durability of the impact absorbing mechanism. It is configured to absorb impact by displacing steel balls in a diameter expanding direction by relative rotation of a driven gear and a driven shaft due to rotational power generated upon meshing and by displacing an axial displacement member in an axial direction against an axial elastic member.

Abstract: An electric hammer comprising a hammer bit performing hammering work on a work, a drive motor, a hammering piece driven by the drive motor to apply a hammering force to the hammer bit, and a mechanism for damping vibration generated during hammering. The damping performance of the electric hammer is enhanced by causing the driving amount applied to the damping mechanism to vary between a first mode where the damping mechanism generates vibration of the hammer bit subjected to an external force from the work during the load driving time and thereby optimizes the damping and a second mode where the damping mechanism generates vibration corresponding to the vibration of the hammer bit not subjected to an external force from the work during the no-land driving time and optimizes damping.

Abstract: The power tool has a power transmitting mechanism. When a tool bit is not pressed against a workpiece, the power transmitting mechanism is held in a power transmission interrupted state, and when the tool bit is pressed against the workpiece, the power transmitting mechanism is held in a power transmission state in which the tool bit moves together with the driven-side member in an axial direction of the tool bit so that the driving-side member receives the torque from the driven-side member and the tool bit is driven. Tapered portions are provided between the driving-side member and the driven-side member and inclined with respect to the axial direction of the tool bit. When the driven-side member moves in the axial direction of the tool bit, frictional force is caused on the tapered portions and the torque of the driving-side member is transmitted to the driven-side member by the frictional force.

Abstract: A power tool having a gear speed reducing mechanism which is free of backlash and a planetary gear speed reducing mechanism. The planetary gear speed reducing mechanism has a driving-side member that is rotationally driven by a prime mover, a driven-side member which is rotatably and coaxially disposed with the driving-side member and to which a tool bit is coupled, and an intervening member which is disposed between the driving-side member and the driven-side member. The intervening member is configured as a planetary member and at least caused to rotate by frictional force acting on its contact surface in contact with the driving-side member when the driving-side member is rotationally driven, so that torque of the driving-side member is transmitted to the driven-side member at reduced speed.

Abstract: It is an object of the invention to provide a technique that contributes to further improvement of an impact tool. A representative impact tool includes a motor, a tool body that houses the motor, a dynamic vibration reducer and a driving mechanism part that is driven by the motor and forcibly drives the dynamic vibration reducer by applying an external force other than vibration of the tool body to the dynamic vibration reducer, during hammering operation. At least one of the dynamic vibration reducer and the driving mechanism part is mounted to the tool body in a form of an assembly into which at least one of a plurality of component parts forming the dynamic vibration reducer and a plurality of component parts forming the driving mechanism part are assembled in advance.

Abstract: A hand-held rotary tool is provided which can offer improved usability while realizing reduction of vibration of a tool body. The rotary tool has a tool body, a drive shaft disposed in the tool body, a driven shaft to which a tool bit is attached, an Oldham's coupling that transmits rotation of the drive shaft to the driven shaft, and an elastic element disposed between the driven shaft and the tool body. The driven shaft is prevented from moving in a longitudinal direction of the driven shaft relative to the tool body and allowed to move in a direction transverse to the longitudinal direction of the driven shaft relative to the tool body. During this relative movement, power transmission from the drive shaft to the driven shaft is maintained via the Oldham's coupling. The elastic element absorbs the movement of the driven shaft relative to the tool body.

Abstract: A controller system includes a terminal device 7, and an input device 200 as an additional device which can be attached to and detached from the terminal device 7. The controller device 7 includes a generally plate-shaped housing 50, and an LCD 51 provided on the front side of the housing. The input device 200 includes an operation section such as a stick 204, a bar-shaped first grip portion 200a, and a support portion 205. The support portion 205 detachably supports the terminal device 7 so that the screen of the LCD 51 is in a generally vertical direction when the first grip portion 200a is in the vertical direction.

Abstract: A hand-held tool has an operation member operably coupled to a lock mechanism. The lock mechanism can lock and unlock the position of a cover that covers at least a part of an end tool. The operation member is positioned on an opposite side to a coupling device that movably couples the cover to a gear head device mounted to a tool body.

Abstract: It is an object of the invention to reduce transmission of an external force caused by run-out of a tool bit to a tool body in a power tool is provided. A representative power tool which performs a predetermined operation by linear motion of a tool bit in its axial direction has a tool body, a tool holder that holds the tool bit in its front end region and extends in the axial direction of the tool bit, and an elastic element. A rear region of the tool holder opposite from the front end region extends into the tool body, and in the extending region, the tool holder is coupled to the tool body such that the tool holder can rotate about a pivot on a z-axis defined by an axis of the tool bit, in directions of y- and x-axes which intersect with the z-axis. The elastic element applies a biasing force to the tool holder in such a manner as to hold the tool holder in a predetermined position or an initial position with respect to the tool body.