Disclosed herein is a cutting apparatus including a moving unit for moving a spindle to position a cutting blade, a rotary dressing mechanism for rotating a dressing grindstone on a rotational shaft parallel to the spindle, and an optical sensor for detecting the position of the outer periphery of the dressing grindstone. The cutting blade is positioned with respect to the rotary dressing mechanism depending on the position, detected by the optical sensor, of the outer periphery of the dressing grindstone, and the cutting blade is dressed by cutting into the dressing grindstone by a predetermined cutting distance.

A space-saving centerless grinding machine having high operability is obtained by devising the configuration of component units around the basic configuration of the machine. A dressing means for performing a dressing process for a grinding wheel and a regulating wheel comprises a single dressing unit. The dressing unit is located at a lower position between the grinding wheel and the regulating wheel, and thus eliminates the need for right and left dresser spaces for grinding wheels that have most seriously affected the breadthwise dimension of a conventional centerless grinding machine, leading to space saving and a considerable reduction in the breadthwise dimension of the centerless grinding machine.

Herein is disclosed a method of dressing a grinding wheel, the method comprising providing a dressing roller and a grinding wheel, wherein the dressing roller comprises a hub and a plurality of polycrystalline diamond (PCD) segments mounted peripherally about the hub, each PCD segment having a pair of side surfaces extending generally radially and an end surface extending generally circumferentially between the side surfaces, the method comprising the steps of: a. rotating the dressing roller and/or the grinding wheel, and b. engaging a periphery of the dressing roller and a periphery of the grinding wheel, wherein a speed ratio qd between the dressing roller and the grinding wheel is below 0 or above +1, and wherein a rake face is located on one of said side surfaces of each PCD segment and a corresponding flank face is located on the end surface.

Herein is disclosed a method of dressing a grinding wheel, the method comprising providing a dressing roller and a grinding wheel, wherein the dressing roller comprises a hub and a plurality of polycrystalline diamond (PCD) segments mounted peripherally about the hub, each PCD segment having a pair of side surfaces extending generally radially and an end surface extending generally circumferentially between the side surfaces, the method comprising the steps of: a. rotating the dressing roller and/or the grinding wheel, and b. engaging a periphery of the dressing roller and a periphery of the grinding wheel, wherein a speed ratio qd between the dressing roller and the grinding wheel is below 0 or above +1, and wherein a rake face is located on one of said side surfaces of each PCD segment and a corresponding flank face is located on the end surface.

A grinding wheel dressing tool with hollow spheres preferably includes a tool shank and a dressing portion. The tool shank preferably includes a shank portion and a tool body. The shank portion extends from one end of the tool body and a dressing portion cavity is formed in an opposing end. The dressing portion preferably includes a quantity of diamond grit, metal bond powder, binder and a plurality of hollow spheres. The dressing portion cavity is preferably filled to a top with metal bond powder. The diamond grit, the metal bond powder and the binder are mixed together to form a grit mixture. A tubular mold is slipped over a top of the tool body. The dressing portion is created by forming alternative layers of grit mixture and hollow spheres in the tubular mold. The tubular mold is heated and the grit mixture pressed with a plunger.

A grinding wheel dressing tool with hollow spheres preferably includes a tool shank and a dressing portion. The tool shank preferably includes a shank portion and a tool body. The shank portion extends from one end of the tool body and a dressing portion cavity is formed in an opposing end. The dressing portion preferably includes a quantity of diamond grit, metal bond powder, binder and a plurality of hollow spheres. The dressing portion cavity is preferably filled to a top with metal bond powder. The diamond grit, the metal bond powder and the binder are mixed together to form a grit mixture. A tubular mold is slipped over a top of the tool body. The dressing portion is created by forming alternative layers of grit mixture and hollow spheres in the tubular mold. The tubular mold is heated and the grit mixture pressed with a plunger.

A dresser apparatus for dressing a grinding wheel, the apparatus comprising a dresser cradle unit for holding a dresser roll, and a rotary drive for driving the dresser roll, wherein the dresser cradle unit is removable from the rotary drive.

A dresser apparatus for dressing a grinding wheel, the apparatus comprising a dresser cradle unit for holding a dresser roll, and a rotary drive for driving the dresser roll, wherein the dresser cradle unit is removable from the rotary drive.