Abstract: An apparatus and method of roughening the sole side surface of a tread band is provided wherein the sole side surface of a tread band is roughened with at least one abrasive roller. The bottom of at least one groove in a tread side of the tread band is supported while the abrasive roller is roughening the sole side surface opposite the supported groove.

Abstract: A dental crown polishing apparatus has a motor, a ball bearing assembly around a shaft of the motor and having balls rotating and circularly moving around the motor shaft by receiving torque from the motor shaft, a brush assembly on the periphery of the ball bearing assembly, equipped with brushes contacting the ball to rotate and having bristles in the same direction as an axial direction of rotation and a tray opposite and open to the brush assembly to dispose a crown toward the brushes. The motor shaft is offset from the center of the brush assembly. The brush assembly moves in an orbital fashion by the rotation of the motor. The tray rotates separately from the brush assembly. The rotation of the tray is not synchronous with the rotation of the brush assembly. Dental crown polishing is achieved by the orbital movement of the brushes.

Abstract: Machine for machining using abrasive belts circular workpieces supported by at least one pair of parallel rollers. To pass the workpieces under the machining station(s) 6, the support rollers 16 driven in rotation are moved in translation parallel to their axes. The rollers 16 are preferably mounted on a table 13 mobile in translation which can also carry means 19 for positioning the workpieces to be machined.