GB215788A - Improvements in blanks for gears and method of making the same - Google Patents

Abstract

215,788. British Thomson-Houston Co., Ltd., (Assignees of Guay, E. J.). May 10, 1923, [Convention date]. Compound sheet materials.-Blanks for helical or other gears are built up from elements cut from a sheet of canvas or duck or other textile material coated with a binder such as phenolic formaldehyde condensation product, the elements and all the trimmings from the sheet being employed in the finished blank and united by compression and, preferably, heat. The canvas &c. is coated on one or both sides with the binder, bakelite with a specific gravity approximately equal to unity preferably being used, and the sheet is dried by heating in a vacuum to remove the solvent. From the square sheet, Fig. 1, circular discs 16 are cut, leaving star-shaped pieces 18 and half-stars 17, which are cut and arranged to form the blank without waste. The parts thus produced are superimposed in a press 28, Fig. 12, heated to soften the binder, and then the plunger 30 is forced down, at first slowly to allow escape of air. The blank is then cooled while still under pressure and finally removed and warmed to complete the. curing process. The finished blank, Fig. 13, has a thin web adapted slightly to yield laterally under heavy shocks.