GB879859A - Improvements in or relating to the manufacture of bearings having elongated movable elements - Google Patents

Abstract

879,859. Making roller bearings; force fits assembling. PITNER, A., and ROULEMENTS A AIGUILLES S.A., DES. Dec. 24, 1957 [Dec. 28, 1956], No. 40124/57. Classes 83 (2) and 83 (4). [Also in Group XXXIV] A process for the manufacture of bearing races for needle bearings or other bearings embodying elongated rolling members, wherein said races possess a convex raceway and a mounting surface having a rectilinear generatrix is characterized in that the generatrix of the radial cross section of the surface of the blank which is intended to form the convex raceway is initially made rectilinear and the generatrix of the opposite surface, which is intended to fit the race on the bearing support, is initially made convex, and the blank is then cold-deformed to invert the shapes of said generatrices. In an embodiment a cylindrical blank is arched, Fig. 2, and the outer surface 6 is cylindrically machined and hardened, Fig. 4. The blank is then forced on to a mandrel 7 so that the blank deforms to produce a hardened convex raceway 9, Fig. 5. In another embodiment the machined blank, Fig. 3, is subjected to profile reversal and hardened on its inner surface 3, Fig. 7, and then forced into a bore 15 in a housing 13 to form a convex race 16, Fig. 8. In another embodiment a cupped blank of cross section 20, Fig. 11, is mounted on a mandrel 23 having a concave portion 24 the blank being pressed on to the mandrel by a tubular die 25 to impart the desired variable thickness of cross-section to the blank. Alternatively the blank 22, Fig. 14, is shaped by a convex profiled roller 31 whilst mounted on a cylindrical mandrel 30. The cupped blank is then cut along the two planes I and II and subjected to the profile reversal operation to form the bearing race. Specification 713,765 is referred to.