GB565031A - Improvements in and relating to apparatus for the manufacture of rods, tubes or plugs - Google Patents

Abstract

565,031. Hoppers. PHILPLUG PRODUCTS, Ltd., and TAYLOR, C. H. March 13, 1943, No. 4155. [Class 78 (i)] [Also in Group V] Apparatus for making rods, tubes or plugs comprises a pair of members, e.g. rollers, having co-operating recesses into which plastic material is fed, and means for expressing the material from the recesses into a nozzle or mould. Three examples are described : (1) (Figs. 1 and 3). Two rollers 1 having co-operating recesses 2 are rotated step-by-step by means including pawls 7, ratchets 8, shafts 15 and cams 20. The cams 20 are mounted on a shaft 21 driven by an electric motor 43. On the shaft 21 is an eccentric or crank 23 which reciprocates a ram 24, the ram passing into and out of the recess 41 formed in the bite of the rollers. Material is fed to the recess 41 by a hopper comprising cushioned plates 35 and 'plates 32 which are vibrated, on pivots 33, by contact with the serrated periphery of the rollers 1. The material is pushed from the recess 41 by the ram 24 through a nozzle 40, and may be cut into lengths. If the recesses 2 coincide exactly, as shown in Fig. 1, their edges must necessarily not meet in the position shown, whereby material is wasted ; to avoid this, they may be slightly staggered. The rollers are resiliently. indexed by devices 42, and are resiliently mounted on their shafts 3. (2) (Figs. 8 and 13). In a modification, for making tubes, the ram has a mandrel-like extension 44, which always extends through the recess and the nozzle. In operation, the rollers are initially together, as in Fig. 1. Then they move apart (Fig. 8), the base of the open recess being closed by a member 45 and the recess being filled with material. Finally, the rollers move together again, the material in the recess being compressed around the mandrel 44, the member 45 descending, and the plunger 24 ejecting the material through the nozzle to form a tube 46' which coalesces with a previously-ejected tube 47 resting on a support 48. (3) (Fig. 15). The ram 24 pushes the material through the recess 41 into (momentarily-closed) mould pockets 51 in an intermittently-rotating disc 50, whence they are later pushed out by another ram 53. The outer ends of the pockets 51 may be closed, at the charging station, by a spring- pressed ball. In general : the parts 40, 50 may be heated electrically. The ram 24 may be circular-section and the nozzle 40 non- circular ; alternatively, non-circular sections may be obtained by making the outlet portion of the nozzle 40 or mould apertures 51 non- circular, the remaining portion being circular in accordance with the shape of the ram. The material used may be that described in Specification 457,523, [Group V].