| 摘要 |
980,789. Forging light metal pistons; composite casting. H. MAHLE, and E. MAHLE, [trading as MAHLE KOMM.-GES.]. Dec. 9, 1963 [Dec. 11, 1962], No. 48464/63. Headings B3A, B3F and B3H. A light metal piston 5, Fig. 4, having a ring carrier 1 of harder material is made by providing a cast blank 2, Fig. 1, with the ring 1 embedded completely therein and then pressing the blank to hollow shape. During casting of the blank, the ring is supported in the shell mould 3, Fig. 2, by supports 31. These form longitudinal indentations 22 on the blank which are removed during the pressing performed in die 41 and bush 43 by means of ram 42. The metal 51 overlying the ring carrier 1 is finally removed by machining. Specification 556,224 is referred to. |
