GB484165A - Segmental grinding wheels - Google Patents

Abstract

484,165. Grinding wheels. NORTON GRINDING WHEEL CO., Ltd. Oct. 29, 1936, No. 29464. Convention date, Nov. 9, 1935. [Class 60] [Also in Group II] In a segmental grinding-wheel, the spaces between the abrasive blocks are filled, or partly filled with a vulcanized hard ribber compound which is deformable in order to avoid strains in the wheel due to temperature changes. As applied to a wheel having a metal or concrete core 10, the segmental blocks 12, arranged in one or more annular courses, are clamped in position by bolts 16, nuts 17, and wedge blocks 14 seating on babbitt metal, &c. 20, and the spaces between the segments and above the wedges are filled with the rubber compound 24. In the form of wheel shown in Fig. 3, wherein the segments 30 are cemented together to form a unitary structure clamped by plates 34 to a shaft 35 a metal reinforcing ring 36, which may comprise steel having about 30 per cent nickel, is embedded in the segments and is cemented in place by means of the rubber compound, by a cement comprising rubber, sulphur and silicon carbide, or by a resinoid, and a resinoid also may be used to cement together the inner portions of the segments, the deformable rubber compound being located in the outer portions 38 of the spaces between the segments ; the resinoid may contain inert fillers. The rubber compound may be of cellular form, made in the manner in which sponge rubber is produced, or may contain large granules of cork, of 14 to 20 grit size, as shown in Fig. 4, wherein the rubber compound is shown at 40 and the cork granules at 42 ; abrasive grains and/or standard fillers also may be included in the rubber compound. In order that the rubber compound may be permanently deformable, or soften, with rising temperature, the compound has admixed therewith a modifying agent, for example, mineral rubber, cumer or paracumerone, beeswax, montan wax, coal tar pitch, petrolatum or brown- or white factice, the amount for example 12 per cent to 20 per cent depending on the degree of deformability required. In all cases, the rubber is combined with not less than 20 per cent of its weight of sulphur. In the manufacture of the wheel, the segments are assembled with sheets of the rubber compound therebetween, clamped by iron bands and raised to the vulcanizing temperature. Specifications 277,013, 285,331, 308,991, and 333,658, [all in Class 60], are referred to.