It is an object of the invention to provide a technique for realizing rational arrangement of components considering arrangement of a tool accessory mounting mechanism in a power tool. A representative electric vibration tool 100 is provided which mainly includes a body housing 101, an inner housing 110, a driving motor 115 and a spindle 124. A blade 145 as a tool accessory is held between the spindle 124 and a clamp shaft 127 and driven by the driving motor 115. A rotation axis of the driving motor 115 and the spindle 124 are arranged in parallel to each other. A clamp shaft 127 is held by a clamp member 131 of a clamp shaft holding mechanism 130. The clamp member 131 is arranged within the body housing 101.

A belt sander includes a frame, a drive roller, an idler roller rotatably attached to a pivot arm, a first linear actuator configured for pivoting the pivot arm, a nose roller and a continuous abrasive belt wrapped around the drive roller, the idler roller and the nose roller. A drive motor rotates the drive roller, and an air cylinder attached to the frame and a nose roller spindle exerts a first force against the frame and a second force equal to and opposite the first force against the nose roller spindle. A first sensor senses a position of a belt edge, and a first controller receives a belt edge position signal from the first sensor and sends a command signal responsive to the position signal to the first linear actuator for expanding or contracting so as to pivot the pivot arm about a pivot point.

The invention refers to power tool (10) comprising a tool housing (12), a motor (24) located therein and a tool shaft (36) with a rotational axis (40) and actuated by the motor (24) when in operation. A distal end of the tool shaft (36) is accessible from outside the tool housing (12). The power tool (10) further comprises a polishing pad (38) releasably attachable to the distal end of the tool shaft (36) from outside the tool housing (12) in an axial direction parallel to the rotational axis (40) and, after attachment to the tool shaft (36), held in respect to the tool shaft (36) in the axial direction by means of an axial holding arrangement (80). The axial holding arrangement (80) comprises a first element (36; 38) constituted by the polishing pad (38) or the tool shaft (36) and a second element (38; 36) constituted by the other one of the tool shaft (36) or the polishing pad (38), and at least one locking element (70) held in the first element (36; 38) movably in a radial direction between a retracted position and a locking position, at least one radially extending recess (76) provided in the second element (38; 36) and configured to receive part of the at least one locking element (70) when in its locking position. The locking elements (70) and the second element (38; 36) in and/or around the at least one radial recess (76) are made of a magnetic or ferromagnetic material so that the locking elements (70) are automatically held in their locking positions and in the at least one radial recess (76) by magnetic force.

The invention refers to hand-held power tool (10) comprising a tool housing (12), a motor (24) and a tool shaft (36) having a rotational axis (40) and actuated by the motor (24), and further comprising a working element (38) releasably attachable to the tool shaft (36) from outside the tool housing (12) in an axial direction and, after attachment to the tool shaft (36), held in respect to the tool shaft (36) by means of an axial holding arrangement (80). The axial holding arrangement (80) comprises a first element (36; 38) constituted by one of the working element (38) and the tool shaft (36) and a second element (38; 36) constituted by the other one of the working element (38) and the tool shaft (36), and at least two locking elements (70) assigned to the first element (36; 38) movably in a radial direction between a retracted position and a locking position, at least one recess (66) assigned to the second element (38; 36) for receiving the locking elements (70) when in their locking positions. The locking elements (70) or the second element (38; 36) in and/or around the at least one radial recess (66) comprises a magnetic material and the at least other one of the locking elements (70) and the second element (38; 36) in and/or around the at least one radial recess (66) comprises a magnetic material or a ferromagnetic material. The locking elements (70) are automatically moved into and held in their locking positions and in the at least one radial recess (66) by means of magnetic force after attachment of the working element (38) to the tool shaft (36).

An apparatus for forming the hairline on a target material according to the embodiment includes a body including a rotation shaft, an abrasive member, a first bracket for fixing the abrasive member to the rotation shaft, and a guide unit disposed between the body and the rotation shaft along a longitudinal direction of the rotation shaft.

A quick change back up pad comprises a grinding disc and a base, and the base is connected between the grinding disc and a grinding hand tool. Wherein, the quick change back up pad comprises a gap formed between the base and the grinding disc and communicated to the outside, and a plurality of air holes communicated with the gap is formed through the base. Accordingly, the plurality of air holes forms an airflow during a rotation process of the quick change back up pad, such that heat energy generated by the operation of the quick change back up pad can be dissipated by the airflow from the gap to the outside of the plurality of air holes, thereby solving a problem that a grinding disc is difficult to perform heat dissipation since a surface thereof is covered during the conventional implementation.

An electric power tool includes an output shaft, drivable by an associated drive motor, and a brake apparatus for braking the output shaft rotating in the unpowered state of the associated drive motor. The output shaft is mounted in a rotatable manner in an associated housing and the brake apparatus has a magnetic-field brake unit with at least one first and one second brake element. The first brake element is arranged radially with respect to the output shaft in a rotationally fixed manner in the associated housing and includes at least one first and one second magnetic pole configured to generate a magnetic field that alternates in the circumferential direction of the output shaft. The second brake element is magnetically conductive and rotationally connected to the output shaft via an activatable coupling device.

A machine tool brake device of a portable machine tool includes at least one magnetic-field-type brake unit that is configured to brake a spindle and/or a machining tool when the magnetic-field-type brake unit is in at least one braking position. The machine tool brake device further includes at least one spindle immobilization unit that is configured to immobilize the spindle when the spindle immobilization unit is in at least one immobilization position. The machine tool brake device also includes at least one activation unit that is configured to transfer the magnetic-field-type brake unit into the braking position and to enable an automatic transfer of the spindle immobilization unit into the immobilization position.

The present invention relates to a method of manufacturing a main body of a grinding tool fixture, a grinding tool fixture having a cap at a front, a sleeve and a coil spring consecutively connected, and a main body connected at a rear, and the main body having a body and a rotating shaft integrally formed with a rear of the body. The main body of the grinding tool fixture is turned, heat-treated, and then straightened. According to the present invention, a grinding tool for a grinder can be conveniently attached and detached by reciprocating a sleeve such that a separate working tool or fastener is not required, and the grinding tool can be immediately replaced even during use of the grinder.

A power tool is provided such that noise can be reduced at a wide range of rotation speeds. A speed setting dial to be operated by a worker is disposed on a rear end part of a housing of a grinder. A control part controls driving of a motor by setting the rotation speed of the motor in response to the value of a speed setting signal which indicates a value (voltage) corresponding to an amount of rotation of the speed setting dial by the worker. Although the control part basically causes the rotation speed of the motor to change continuously in response to the rotation amount of the speed setting dial, the control part sets the rotation speed of the motor while avoiding a predetermined rotation speed region in which the noise level is increased due to mechanical and acoustic resonances.