Abstract: The invention relates to an improved grinding wheel for grinding eye glass edges. The grinding wheel comprises a base member and an abrasive coating of diamond and metal. The base member 3 consists substantially of plastic material and an annular member 2 of metallic material is provided between the base member 3 and the coating 1. The metallic material of the annular member 2 has a strength withstanding the forces occuring in sintering the coating to the annular member.

Abstract: The present invention relates to a grinding wheel for surface cutting of workpieces, comprising a carrier wheel and an abrasive lining which is composed of a plurality of individual hexagonal and equilateral grinding portions which are secured to the carrier plate.

Abstract: A saw comprises a saw blade having an outer edge, and a diamond-containing coating carried on the outer edge of the saw blade, the saw blade being composed of a synthetic plastic reinforced with a fiber material composed of a plurality of fibers with a volume fraction of 30-70%.

Abstract: A saw comprises a saw blade having an outer edge, and a diamond-containing coating carried on the outer edge of the saw blade, the saw blade being composed of a synthetic plastic reinforced with a fiber material composed of a plurality of fibers with a volume fraction of 30-70%.

Abstract: In accordance with a method of producing metal sinter bodies, the bodies are provided with degassing openings which are made preferably before sintering of an initial press body part.

Abstract: A saw comprises a saw blade having an outer edge, and a diamond-containing coating carried on the outer edge of the saw blade, the saw blade being composed of a synthetic plastic reinforced with a fiber material composed of a plurality of fibers with a volume fraction of 30-70%.

Abstract: A grinding or separating tool has a base body with a synthetic plastic max and a plurality of reinforcing fibers, a working coating a plurality of hard grains, and an intermediate layer applied on the base body and located between the base body and the working coating so that the fibers of the base body extend outwardly beyond the plastic matrix of the base body and are embedded in the intermediate layer.

Abstract: A grinding wheel for deep grinding comprises a main body, and a diamond coating on the main body, the diamond coating including a first coating part with fine grain diamonds and a second coating part with diamonds of greater size, the second coating being composed of a plurality of diamond grains which are arranged in one layer as considered in a direction parallel to a feeding direction of the diamond wheel and in a plurality of layers as considered in a direction perpendicular to the feeding direction, the diamond grains of the second coating part being arranged in direct contact with one another and held in a galvanically deposited binder.

Abstract: Diamond grains utilized in cutting tools and usually held in a bond, specifically metallic bond are subjected to a pretreatment which enlarges their surface to at least twice their natural surface area. The pretreatment includes embedding the diamond grains in a metal powder, and exposing the embedded grains to a stream of hydrogen or hydrogen-containing gas at a temperature above 700.degree. C. until pores are etched in contact areas of the diamonds with the metal particles. The pretreated diamond grains are then purified with an acid to remove the metal particles and other residues.

Abstract: Grinding of non-round workpieces with plunge cutting on circular grinding machines is performed by a grinding disc which is coupled with a dressing roller and which is also kinematically coupled to a workpiece, so that the grinding is performed in condition of the kinematic coupling.

Abstract: Apparatus for exhibiting grains of precious stone comprises in a container assembly at least two communicating compartments, which communicate with each other through at least one passageway, which constitutes a singling path for grains of precious stone. That communicating passageway is constricted so as to permit singled grains having a given size to move freely through the passageway. The container assembly contains an aggregation of grains of precious stone. The at least two compartments communicating with each other have different elevations. The communicating passageway is defined by a slideway, which is inclined from the vertical, or constitutes a path for a free fall of grains of precious stone from the aggregation. Such apparatus can be used as a sales display container, an ornament, or a gift article.

Abstract: A saw for cutting thin disks from a bar includes a thin blade provided with an inner hole and having in the peripheral region of that hole a diamond coating which has a different thickness on two opposing external sides of the blade to avoid bending of the blade due to a non-uniform loading of the blade. The coating is thicker on the non-stable side of the blade, which faces the disk being cut off.

Abstract: A wear-protective layer for cutting tools is formed by the chemical vapor deposition or chemical plasma deposition or plasma sputtering by depositing a plurality of layers to a support of the cutting tool to form a multilayer in which each successive layer remoter from the support has a higher elasticity module and a greater diamond portion than the preceding layer. The outermost layer is a layer of diamond.

Abstract: A dressing tool for grinding wheels includes a base body and a diamond coat which is formed of diamond grains embedded in a metallic bond. The diamond grains are artificially roughened so that their surface area is significantly enlarged and are arranged in the metallic bond with such density that the majority of grains are in direct contact with adjacent grains.

Abstract: Dressing of grinding wheels is performed by a dressing tool which is displaced first to be brought into contact with a grinding wheel and the contact is determined by measuring an electrical voltage of a piezoelectric element connected with the dressing tool, and then feeding of the dressing tool relative to the grinding wheel for dressing is performed by applying an electrical voltage to the piezoelectric element.

Abstract: A method and a device for controlling a drive of successively operated grinding disks which are made of different compositions. The condition, for example metallic inclusions or the like, in each individual grinding disk is scanned by means of a sensor the signal of which is fed to a signal transmitter and stored in a storage connected to the drive of the grinding disks, which is thereby controlled.

Abstract: A method and device for sharpening and scouring a grinding disk having a grinding medium, in which a feeding velocity of a sharpening block is adjusted by a first drive means connected to the sharpening block for sharpening the disk and a feeding force applied to the sharpening block is adjusted by a second drive coupled to the first drive whereby the adjustable feeding velocity is reduced when the feeding force reaches its maximum allowable value.

Abstract: A method of trueing grinding disks comprises the steps of engaging the outer layer of a grinding disk during rotation thereof with a predetermined speed with a driven diamond trueing roll and spaced from the trueing roll with a trueing disk having a peripheral speed of 0.5-6 meters per second and preferably 1 meter per second relative to the peripheral speed of the grinding disk. The trueing of the grinding disk can be performed while the grinding disk grinds a workpiece.

Abstract: A method for profiling of grinding wheels with diamond and/or cubic crystalline boron nitride, and apparatus for carrying out this method wherein a profiled roller and an abrasive block with corundum or silicon carbide are simultaneously pressed against the contour surface of a grinding wheel.