GB667141A - Method of shaving gears - Google Patents

Abstract

667,141. Gear - finishing. NATIONAL BROACH & MACHINE CO. Oct. 5, 1949 [Jan. 13, 1949], No. 25615/49. Class 83 (iii). A method of finishing a cylindrical gear W consists in meshing the gear with a cylindrical gear-like cutter C having cutting-edges at the leading edges of the teeth, the axes of the gear and cutter being crossed, and rotating the gear and cutter independently in accurately-timed relationship while effecting a slow relative traverse in a direction parallel to the axis of the gear. The cutter C is mounted on a table 20 adjustable angularly about a shaft 24 and is traversed by a screwed shaft 63 coacting with a nut 64 in a slide 13. The work-spindle 16 is vertically-adjustable on a column 11. The cutter C, the work W, and the screw 63 are rotated by an electric motor 25, the traverse of the table being compensated by a differential gear 52, 53. The cutter C may be backed-off as shown or may have unrelieved teeth, the cutter-spindle being then suitably inclined. Alternatively, if the cutter is unrelieved, it may be set with the point of crossed axes spaced from the cutting-edges, the cutter then engaging the work-piece in a position to the left of that shown. The crossed-axis angle is preferably 10-20 degrees. The peripheral surface speed of the cutter is several hundred feet per minute and the transverse rate is a few thousandths of an inch per gear revolution. After one stroke, relief may be introduced between cutter and gear, and the sliide 13 returned rapidly to its initial position. Specification 601,758 is referred to.