An air cylinder that changes the posture of an automatic wet sanding unit main body having sandpaper mounted thereon is provided with a guide rod, and an outer circumferential surface of the guide rod has grooves that extend along a shaft centerline of the guide rod and have an arc-shaped cross-section. Balls are interposed between a bottom of each groove and an inner surface of a bush that is provided inside the air cylinder. Thus, it is possible to make two objects compatible with each other: to achieve high-accuracy automatic wet sanding by enhancing the adaptability of the sandpaper to the shape of a painted surface through a reduction of the diameter of the piston rod; and to enhance the durability of the automatic wet sanding apparatus.

A method for automatically attaching a surface treatment medium to a head of a surface treatment tool mounted on an articulated arm of a robot is disclosed. The method comprises placing the head on a surface and applying a predefined force to press the head towards the surface when no surface treatment medium is attached to the head, measuring the distance between the head and the surface using one or more positioning sensors of the robot arm or the surface treatment tool, attaching a surface treatment medium to the head, placing the head on the surface when the surface treatment medium is attached to the head, and measuring the distance between the head and the surface using one or more positioning sensors of the robot arm or the surface treatment tool when the surface treatment medium is attached to the head.

In an automatic wet sanding apparatus including a paper peeling unit that has a clamping shaft and a clamping hook, an inclination angle of a leading end surface of the clamping hook is equal to an inclination angle of an outer circumferential surface of a cushion pad at the start of a paper peeling step. Thus, the leading end surface of the clamping hook comes into contact with an outer circumferential end of a disc at the same time as coming into contact with the outer circumferential surface of the cushion pad, so that the cushion pad is less likely to get caught due to deformation of the outer circumferential surface and its peripheral part of the cushion pad. It is therefore possible to appropriately remove the sandpaper from the cushion pad and stably perform the task of removing the sandpaper.

A dual sided abrasive article is presented that includes a first side with a first abrading face and a second side, with a second abrading face. The second side is opposite the first side and separated by a thickness. The article also includes a center hole extending from the first side to the second side through the thickness. The article also includes a fastener for coupling the abrasive article to a powered tool, the fastener positioned within the center hole.

A method and a machine for automatically changing a disc tool to a tool holder of an automated machine working with the disc tools is disclosed. The method includes in the disc tool replacement machine: determining that the tool holder is in a replacement area in the disc tool replacement machine; unfastening a fixing member of the tool holder by applying an unfastening force to the fixing member, wherein the fixing member fixes a disc tool to a backing plate of the tool holder through a through hole at a centre of the disc tool; removing the disc tool from the tool holder after said unfastening; inserting a new disc tool to the tool holder; and fastening the fixing member of the tool holder by applying a fastening force to the fixing member, thus fixing the disc tool to the backing plate of the tool holder through the through hole.

A device for automatically removing a grinding wheel from a grinding machine mounted on a manipulator is described. According to one embodiment, the device has the following: a support plate with a surface for depositing a grinding wheel; a movable clamping element that is raised in a first position with respect to the support plate; an actuator that is coupled to the clamping element and is configured to move the clamping element into a second position in which the clamping element is pressed against the support plate such that the grinding wheel is clamped between the support plate and clamping element; and a release element that is arranged in such a way relative to the support plate that the release element is actuated when the grinding wheel is placed on the surface of the support plate and is pressed against the latter. The release element and the actuator are coupled (directly or indirectly, electrically or mechanically) such that, when the release element is actuated, the actuator moves the clamping element from the first position into the second position.

In order to provide a tool holder for holding a tool for treating the surface of a workpiece by means of which it is possible to treat workpieces in a low-vibratory and convenient manner, it is proposed that the tool holder comprise a disk-shaped base body which has an attachment section for the attachment of the tool holder to a machine tool and at least one resiliently flexible deformation section.

An apparatus includes a frame, a separating plate connected to the frame, a sensor aimed at the separating plate, and a support surface connected to the frame. The separating plate and the support surface are coupled with the frame so as to allow for a relative movement between the separating plate and the support surface in a first direction. The separating plate and the support surface are arranged such that when a grinding disc rests against the support surface and when the separating plate and the grinding disc move towards each other, at least one first edge of the separating plate is pushed over grinding disc. The sensor is arranged such that when the separating plate is pushed over the grinding disc, the grinding disc is between the sensor and the separating plate.

A backerplate for a portable drywall sander hub assembly includes a mounting portion and a backerplate body. The mounting portion includes a threaded bore adapted to couple the backerplate to a sander hub. The backerplate body is connected to the mounting portion. The backerplate body forms a plurality of apertures therein positioned radially between an outer circumference of the backerplate body and the mounting portion. The plurality of apertures are adapted for dust to pass therethrough during operation of a drywall sander with the backerplate mounted thereto.

An apparatus for the robot-assisted machining of surfaces is described. In accordance with one embodiment, the device comprises the following: a support which can be mounted on a manipulator, a machining device with a tool (e.g. a grinding disc) and a linear actuator for adjusting the relative position of a tool in relation to the support. The apparatus further has a maintenance unit comprising a swiveling bracket. The bracket is swivel-mounted on the support such that, by swiveling the bracket, the maintenance unit can be positioned at least partially before the tool.