GB202973A - Improvements in electromagnetic work fixing devices - Google Patents

Abstract

202,973. Krupp Akt.-Ges., F. Aug. 22,1922, [Convention date]. Void [Published under Sect. 91 of the Act]. Electromagnets. - Comprises an electromagnetic work-holder in which the work-holding plate is separated from the casing by a watertight layer. The casing A is of cast steel and encloses an exciting winding B, which is covered by a wrought-iron plate A<2>, secured to a thickened portion a<1> of the casing, and having its upper face in the same plane as the upper face of the casing wall a<3>. A thin sheet-iron plate E rests on the plate A<2> and on the wall a<3>, and upon this plate rest a frame C and a plate D, which are respectively bolted to the wall a<3> and to the plate A<2>. The frame C, Fig. 4, has crossbars c<1>, and the plate D has bars d<1>, Fig. 7, which project into the spaces between the bars c with surrounding air gaps, as shown in Fig. 1. The plate A<2> may be omitted, the upper surface of the portion a<1> then being in the same plane as that of the casing walls. The frame C has outlet channels c for cooling-liquid. The spaces between the bars c<1>, d<1> may be filled with non- magnetic material, for example, brass, and the plate E may consist of non-magnetic material, for example, zinc. In a modification, Fi.g. 9, the work-holding plates comprise an inner poleplate F and an outer part consisting of four bars G screwed to the casing wall; the plate A<2> is omitted. The work-holding plate may comprise a cover with inserted pole cores and surrounding non-magnetic sleeves.