| 摘要 |
1469847 Mould construction RHONEPROGIL SA 18 Dec 1974 [18 Dec 1973 29 Nov 1974] 54694/74 Heading B5A A plaster panel 7 (Fig. 2) (e.g. of phosphogypsum) having tongued and grooved edges, is cast in a mould comprising opposing vertical walls 2 sandwiching neoprene or silicone edge strips 3 and metal spacers 8. When a pressure force 5 is applied to the walls 2, the walls move relatively closer and the strips 3 are deformed to seal the mould; on removal of the pressure force 5 after casting, the strips 3 return to their original shapes to spring the walls 2 away from the plaster. The moulds are built up in banks (Fig. 4) on a fixed base 11, and stripping is aided by using walls 2<SP>1</SP> that are normally bowed, but are flat during moulding. The edge strips 3 can include polished metal inserts that define projections 4 (Fig. 2), or can comprise a sealed plastics jacket filled with a compressible fluid. Alternatively, two such jackets per strip are used, with one sealing the the walls 2 and the other forming the projection 4; the jackets are pneumatically or hydraulically inflated and deflated to effect moulding and springing apart of the mould walls. Finally the strips 3 can comprise a mechanic device deformable by a piston and cylinder. |
