A polishing brush (1) includes a brush-shaped grindstone (12) holding grinding element bundles (11) of wire-shaped grinding elements (27) in an annular shape and a grinding element displacement-restricting member (13) for restricting displacement of the grinding element bundles (11) outward. The brush-shaped grindstone (12) has a grinding element holder (15) holding the base end portions (upper end portions) of the grinding element bundles (11). The grinding element displacement-restricting member (13) has an annular part (33) surrounding the wire-shaped grinding elements (27) from the outer peripheral side at a position between the tip ends of the wire-shaped grinding elements (27) and the grinding element holder (15) in the direction of the axis of center of rotation (L) and at a distance away from the tip ends of the wire-shaped grinding elements (27) and the grinding element holder (15). Since the portions on the side closer to the grinding element holder (15) of the grinding element bundles (11) held in the grinding element holder (15) are exposed outward, cutting fluid or air supplied from the outer peripheral side of the polishing brush (1) easily reaches the polished portion of a workpiece.

A polishing brush (4) includes a grinding element bundle (9) formed with a plurality of wire-shaped grinding elements (28) formed by impregnating and solidifying an assembly of inorganic filaments with resin, and a grinding element holder (7) having a holding hole (20) holding the base end portion of the grinding element bundle 9 on an outer peripheral side surface (7c) serving as a grinding element-holding surface. The grinding element bundle (9) has a front surface (9a) facing forward in a rotational direction (R1) and a back surface (9b) facing backward. The grinding element bundle (9) is held in the grinding element holder (7) such that the front surface (9a) and the back surface (9b) are inclined in the same direction relative to a virtual surface (30) that includes a center point (P) of a cross section (9d) of the grinding element bundle (9) cut across an outer peripheral side surface (7c) and the axis of center of rotation (L) of the grinding element holder (7) and extends in a radial direction. The wire-shaped grinding elements (28) included in the grinding element bundle (9) are easily displaced and can release excessive force applied thereto.

A polishing brush (4) includes a grinding element bundle (9) formed with a plurality of wire-shaped grinding elements (28) formed by impregnating and solidifying an assembly of inorganic filaments with resin, and a grinding element holder (7) having a holding hole (20) holding the base end portion of the grinding element bundle 9 on an outer peripheral side surface (7c) serving as a grinding element-holding surface. The grinding element bundle (9) has a front surface (9a) facing forward in a rotational direction (R1) and a back surface (9b) facing backward. The grinding element bundle (9) is held in the grinding element holder (7) such that the front surface (9a) and the back surface (9b) are inclined in the same direction relative to a virtual surface (30) that includes a center point (P) of a cross section (9d) of the grinding element bundle (9) cut across an outer peripheral side surface (7c) and the axis of center of rotation (L) of the grinding element holder (7) and extends in a radial direction. The wire-shaped grinding elements (28) included in the grinding element bundle (9) are easily displaced and can release excessive force applied thereto.

The present invention is directed to a method and apparatus for polishing stone and synthetic substrates. The apparatus uses a leather polishing pad to apply a finish to a stone or synthetic substrate. The pad has a specially designed fluid channeling pattern which cools by maintaining a quantity of liquid polishing slurry centrally of the pad for cooling purposes. The grit and amount of the abrasive used with the slurry varies based on the mechanical properties of the substrate.

There is described a method, apparatus and shaping tool for shaping a workpiece. The tool comprises a flexible support surface on which are mounted a number of rigid pellets (84) carrying abrasive material. The tool is driven, in contact with the workpiece surface (S), to perform a ductile grinding operation which results in a finished surface of reduced roughness as compared to conventional grinding operations, while achieving significantly higher material removal rates than comparable ultra-precision grinding techniques. A procedure for preparing the tool for operation by conditioning the tool against a conditioning surface is also described. An exemplary application for the method and apparatus is in the preparation of moulds for moulding curved glass components for use in display screens, in which process a silicon carbide mould cavity surface is shaped using the method to produce a mould cavity surface with a smooth surface finish.

The invention relates to a polishing disc for a tool for fine processing optically active surfaces on spectacle lenses, having a main body which has a central axis and to which an intermediate layer that is softer than the main body and is made of a resilient material is secured, a polishing medium carrier resting on the intermediate layer. The intermediate layer has at least two regions with different degrees of hardness, said regions being arranged one behind the other in the direction of the central axis of the main body. The intermediate layer region adjoining the main part is softer than the intermediate layer region on which the polishing medium carrier rests.

Dynamic regulation of contact pressures in a blade sharpening system is provided. An example multiphase grinding wheel has a grinding face with one or more abrasive concentric rings for sharpening the cutting blade of the log saw machine, and one or more padded concentric rings consisting of fiber padding. Sharpening with the multiphase grinding wheel improves cut quality, increases blade life, removes glues and varnishes from the cutting blade, reduces blade deformation, and hones the edge of the cutting blade. A pneumatic tensioning system uses air bladders to apply dynamic cushioning and processor-controlled contact pressure between the grinding wheels and the cutting blade during sharpening. The fiber-padded grinding wheels and the air bladder tensioner provide improved sharpness of the cutting blade and longer life for the mechanical components.

Dynamic regulation of contact pressures in a blade sharpening system is provided. An example multiphase grinding wheel has a grinding face with one or more abrasive concentric rings for sharpening the cutting blade of the log saw machine, and one or more padded concentric rings consisting of fiber padding. Sharpening with the multiphase grinding wheel improves cut quality, increases blade life, removes glues and varnishes from the cutting blade, reduces blade deformation, and hones the edge of the cutting blade. A pneumatic tensioning system uses air bladders to apply dynamic cushioning and processor-controlled contact pressure between the grinding wheels and the cutting blade during sharpening. The fiber-padded grinding wheels and the air bladder tensioner provide improved sharpness of the cutting blade and longer life for the mechanical components.

An extender for a buffing pad assembly having a first portion configured to be rotated, thereby transferring power from a power tool to a buffing pad, and a second portion that can be held by a user to support, direct, and/or control the buffing pad during operation of the power tool. The extender preferably includes a shaft, a sleeve, and at least one retainer for fixing the sleeve onto the shaft. The shaft preferably includes a first portion near a first end, a second portion near a second end, and a third circular portion located therebetween. In one embodiment, the shaft includes first and second grooves, thereby allowing a first retainer (e.g., C-clip) to be snapped into the first groove, the sleeve slid over the open end of the shaft, and a second retainer (e.g., C-clip) snapped into the second groove, resulting in a fully assembled extender.

An extender for a buffing pad assembly having a first portion configured to be rotated, thereby transferring power from a power tool to a buffing pad, and a second portion that can be held by a user to support, direct, and/or control the buffing pad during operation of the power tool. The extender preferably includes a shaft, a sleeve, and at least one retainer for fixing the sleeve onto the shaft. The shaft preferably includes a first portion near a first end, a second portion near a second end, and a third circular portion located therebetween. In one embodiment, the shaft includes first and second grooves, thereby allowing a first retainer (e.g., C-clip) to be snapped into the first groove, the sleeve slid over the open end of the shaft, and a second retainer (e.g., C-clip) snapped into the second groove, resulting in a fully assembled extender.