GB308064A - Improvements in or relating to centreless grinders - Google Patents

Abstract

308,064. Hughes, V. A. B., (Cincinnati Grinders, Inc.). Feb. 25, 1928. Centreless grinding; guides and rests. - In centreless grinding machines the work is supported in the grinding throat by a blade and is fed laterally towards the grinding wheel by a yielding regulating wheel until a positive adjustable stop is encountered. Instead of floating in the throat the work is guided by means exterior to the throat so as to form a cylindrical surface concentric with an internal bore or with a previously formed surface on or attached to the work. When operating on a sleeve or bush 10, the latter is mounted on a mandrel 11 whose ends are engaged by two pairs of rollers 27 rotatable on pins 26 carried by brackets 23 pivoted on spindles 21, while solid work pieces have their previously machined ends engaging the rollers. The surface of the work being operated upon is supported by a blade 16, vertically adjustable at 18 and locked by screws 19 in a fixed bracket 14 which carries the spindles 21. The brackets 23 have hoods 28 to protect the rollers from cutting fluid &c. and are adjusted to position the rollers for deter. mining the final size of the work by screws 29, one of which engages a fixed stop on the bracket 14 while the other engages a cam 37 rotatable by a hand lever to move the rollers to the workreceiving and cutting positions alternately. Springs 34 assist in removing the rollers from operative position. The regulating wheel may be made of rubber or other yielding material, or its slide may be fed towards the grinding wheel through the medium of springs so as to allow it to accommodate itself to eccentricities in the work and to yield when the work engages the rollers 27. The work may be removed by an ejector rod 42 actuated from a handle 45 through a lever 44, or both the ejector and the regulating wheel may be operated automatically.