GB191406751A - Improvements in and relating to the Manufacture of Artificial Stone, Tiles and the like Moulded Ceramic and similar Products. - Google Patents

Abstract

6751. Marks, E. C. R., [Davidson, S., Shantz, J. B., and Ellis, J. W.]. March 17. Moulding pulp; moulds.-In moulding artificial stone products by suction, air &c. under pressure is forced through the strainer to keep it clean and free from clogging deposits. Fig. 4 shows one form of apparatus, in which the wet stone mass 13 is moulded in sand 12 supported by a filter 14 comprising a fabric 60, Fig. 5, enclosed between gauze 20, 21, and providing a space 22 which is connected by a pipe 23, Fig. 4, through valves 41, 42, to a vacuum hose 44 and pressure hose 45 respectively. The valves 41, 42 are operated simultaneously by a link 43, the action being such that exhaust and pressure are alternately applied for brief intervals. The hose 45 may be connected to a dry steam or hot or cold air supply. In a modification, the filter 14 is in the form of a hose embedded in the sand 12. Fig. 8 shows a modified form of apparatus, comprising a mould built up of perforated bottom, side, and top sections 51, 52, 67, fitted into a casing 46 in such a manner as to form chambers 56, 57 which are connected to pressure and exhaust through valves 63, 62. The cover 68 is furnished with a pressure supply-pipe 69 controlled by a valve 70 and an outlet 71 for expressed water. In operation, the pressure valve 70 is opened causing the top plate 67 to press down upon the mixture and expressing a portion of the moisture. The valve 70 is then closed and the valve 72 opened for the escape of the air, which carries off the water with it. The valve 62 is then opened to withdraw superfluous water and air, after which the valve 62 is closed and the valve 63 opened to admit hot or cold air. The operation of suction followed by pressure may be repeated several times if necessary. To discharge the article, a board is placed upon the top of the casing 46 and the whole inverted. The casing 46 is then removed and the strainer plates withdrawn by a sliding action. Fig. 9 shows a somewhat similar apparatus for circular articles in which a sectional mould 76 and a strainer core 77 are employed. For producing blocks with irregular faces, a sand pattern 87, Fig. 12, of the irregular face is employed.