| 摘要 |
924,443. Ball-bearings. EISENWERK ROTHE ERDE G.m.b.H. Dec. 12, 1960 [Dec. 12, 1959], No. 42721/60. Class 12 (1). [Also in Group XXII] A method of producing light metal alloy supporting rings for ball-bearings provided with steel races is characterized in that a ring blank consisting of a ductile light metal alloy, having a uniform cross-section all round, is heated to above the solidus point of the alloy and, after quenching, is clamped in a device in which it is expanded all round uniformly to above a stress value at which it undergoes a permanent increase in diameter. A ring blank 7, Fig. 2, or 8, Fig. 3, of an alloy of Al, Zn, Mg and Cu having 0.5 to 1.5% Cu, is made by piercing a billet on a mandrel, and hot-rolling to form a seamless ring, then heating to 460‹ C., i.e. above the solidus, quenching in a salt bath for about twenty minutes and pre-turning to the desired cross-section. The blank 7 is then expanded by segments 11 urged outwardly by an expander cone 10 moved down by hydraulic or eccentric means. The blank 8 is expanded by hydraulic fluid under pressure supplied to an annular chamber 17 through bores 18. The expanded blank 7 or 8 is then heat-hardened and the blank 7 machined to form a supporting ring 2 or 3 and the blank 8 machined to form the supporting ring 1. The rings 2 and 3 are connected together and to a steel housing ring 23 by bolts 21 having a reduced shank portion 25 in the ring 3 so that in the event of heating, when the bearing expands more than the ring 23, the shank 25 may bend. The ring 1 is bolted to a steel housing ring 29 by a bolt 26 having a reduced shank portion 26a. The rings 1, 2 and 3 support balls running on wire race elements and guided in ball cages. In another embodiment, Fig. 5, a light metal alloy supporting ring 41 is bolted to a light metal alloy ring 42 in turn bolted to a light metal alloy ring 32. A steel housing ring 39 supports the ring 42 on a conical surface 45 so that when the bearing is heated differential expansion causes the conical surface of the ring 42 to slide against the action of springs 34. A supporting ring 30 bolted to a ring 32 has a conical face 44 bearing on a steel housing ring 36. |
