A planarization processing device for polishing a substrate, e.g., a semiconductor wafer, includes two planarization processing sections (SP1, SP2) that each include a holder (62) for holding a workpiece (W), a drive motor (71) that rotates the holder (62), a support plate (4) holds a pad (5), a linear guide (3) that guides reciprocal movement of the support plate (4) in a direction parallel to the surface of the pad (5), and a drive cylinder (72) that advances the holder (62) or the support plate (4) in a direction that intersects the surface of the workpiece W or the pad (5) to cause the opposing surfaces of the workpiece and the pad (5) to be at least proximal to each other. A primary driver (PD) causes the support plates (4) of the planarization processing sections (SP1, SP2) to reciprocate along the same straight line in opposite phases.

An attachment for a mobile handling device is configured for processing walls or ceilings. The attachment comprises a mounting unit that is arranged to be supported at a mounting interface of the handling device, a processing head that is arranged to be equipped with at least one tool for material-removing processing or smoothing processing, and a compensation arrangement that is arranged between the mounting unit and the processing head and that defines a longitudinal axis. The mounting unit provides at least two pivot positions for the attachment that are offset from one another. The processing head is movable relative to the mounting unit in a longitudinal direction along the longitudinal axis. The compensation arrangement is configured to provide a defined contact pressure force for the processing head in a defined operating range along the longitudinal axis towards the surface to be processed.

The invention refers to a hand-held and hand-guided random orbital polishing or sanding power tool (1). The tool (1) comprises a static body (31), a motor (15), an eccentric element (17) driven by the motor (15) and performing a rotational movement about a first rotational axis (10), and a plate-like backing pad (9) connected to the eccentric element (17) in a manner freely rotatable about a second rotational axis (16). The first and second rotational axes (10, 16) extend essentially parallel to one another and are spaced apart from one another. In order to provide for a power tool (1) particularly quiet and low in vibrations, it is suggested that at least part of an external circumferential surface of the eccentric element (17) has an at least discrete rotational symmetry in respect to the first rotational axis (10); the power tool (1) comprises at least one first bearing (30) provided between the rotationally symmetric part of the external circumferential surface of the eccentric element (17) and the static body (31) of the power tool (1) so that the eccentric element (17) is guided in respect to the body (31) in a manner rotatable about the first rotational axis (10); and the power tool (1) comprises a mechanical gear arrangement (21) with at least two meshing gear wheels (27, 28, 29, 29.1, 29.2), wherein the gear arrangement (21) is provided functionally between a driving shaft (18) driven by the motor (15) and the eccentric element (17) and wherein at least one of the gear wheels (27) is attached to the eccentric element (17) in a manner adapted for transmitting torque to the eccentric element (17).

A machine tool (1, 100) comprises a support structure (4, 104) and a machining head (8) bearing a mandrel (12). The machine further comprises at least one action device (20) contained on the support structure (4,104) and applied to it, which generates pushing or pulling actions on said support structure (4, 104) acting against the action of the weight of the head (8) thereon.

The invention relates to an electric hand-held tool with a tool mount, a motor for driving a tool fastened in the tool mount, and a housing which includes a handle area, a motor area for accommodating the motor, and in which vent openings are configured for the ventilation of the motor. At least in the area of the vent openings, the housing is provided with at least one cover with a closed surface, said cover sitting flush against the housing with an edge area facing the tool mount, being arranged at a distance from the housing in an area above the vent openings, and leaving a gap between the cover and the housing in the area of its edge area facing away from the tool mount.

The present invention relates to an actively dampened centerless grinding process for a centerless grinding machine having wheels, between which there is arranged a part to be ground, and heads carrying the wheels, which process has moving the wheels closer to one another by applying pressure on the part for the grinding thereof, such that vibrations are generated in the grinding machine due to grinding, measuring the vibrations due to grinding, and introducing, depending on the measurement, an active damping force (F.sub.act) parallel to the force flow of the grinding machine and by means of using an inertial actuator acting directly on one of the heads, such that the vibrations due to grinding are attenuated.

A power tool includes a housing, a motor, an output shaft, a working head, a transmission assembly, an auxiliary handle, and a vibration damping assembly. The auxiliary handle includes a front end mounted at a position of the housing adjacent to the working head, and further includes a gripping portion extending along a center line. The vibration damping assembly includes a mass member and an elastic element. The auxiliary handle further includes an end cap arranged at a rear end of the gripping portion where the rear end is far away from the housing relative to a front end of the gripping portion. An accommodating cavity for accommodating the vibration damping assembly is formed around the gripping portion when the end cap is combined with the gripping portion. The elastic element is arranged between the mass member and a cavity wall of the accommodating cavity, and a ratio of a natural frequency W1 of the vibration damping assembly to a rotation frequency W2 of the output shaft in rotation is greater than or equal to 0.7 and less than or equal to 1.3.

A grinding apparatus includes a holding table for holding a wafer, a support table for supporting the holding table, a motor for rotating the support table, a frame member supporting the support table for rotation, and at least three support poles for supporting the frame member from the base. Each of the support poles has formed in the inside thereof a through-hole, a supply port which communicates the through-hole and an air supply source with each other, and an exhaust port which exhausts air having flowed through the through-hole toward the support table. Air is supplied into the through-hole to cool the support pole, and the air having flowed through the through-hole is exhausted toward the support table.

An abrasive tool comprises an arbor having a body formed with an internal bore, a mounting plate disposed on the arbor, a cover plate, an abrasive article disposed between the mounting plate and the cover plate, and at least one internal resilient member disposed within the internal bore of the arbor.

A grinding apparatus includes grinding wheel side vibrational displacement calculation devices that obtain a vibrational displacement of a grinding wheel resulting from a vibration in an approaching/separating direction of the grinding wheel; main spindle side vibrational displacement calculation devices that obtain a vibrational displacement of a workpiece generated by propagation of the vibration in the approaching/separating direction of the grinding wheel; a relative vibrational displacement calculation unit that obtains a relative vibrational displacement between the grinding wheel and the workpiece based on the vibrational displacement of the grinding wheel and the vibrational displacement of the workpiece that have been obtained; a position change unit that creates, based on the obtained relative vibrational displacement between the grinding wheel and the workpiece, a position change command to change a position of the wheel spindle stock; and a processing controller that grinds the workpiece W based on the created position change command.