| 摘要 |
PCT No. PCT/GB94/00357 Sec. 371 Date Aug. 4, 1995 Sec. 102(e) Date Aug. 4, 1995 PCT Filed Feb. 23, 1994 PCT Pub. No. WO94/20241 PCT Pub. Date Sep. 15, 1994A piston (10) containing a cavity (16) is manufactured by forming a box (20; 50; 70; 80). The interior of the box defines the cavity (16). The box ms mounted in a die cavity (26) and the piston is cast around the box. The box is provided with projections (22c; 24c; 52; 58; 73) which enter recesses in the wall of the die cavity and support the box. After removing the piston from the die cavity, the projections are machined off. |
