Patent GB-1136323-A (GB)
Title: Mould filling apparatus
IPC: B29C31/04
Filed: 1966-08-24
Abstract: 1,136,323. Filling moulds with granular material. R. B. BUONAIUTO. 24 Aug., 1968 [9 Sept., 1965], No. 37912/66. Heading B5A. [Also in Divisions B1 and B8] In apparatus for moulding foamed or expanded polystyrene from moisturized beads by radio frequency heating thereof, a plurality of mould units 10 are spaced about the periphery of a horizontal rotatable table 12 for delivery at a plurality of stations including a mould filling station where a bead metering unit 16 receives a measured amount of beads from a gravity supply hopper 20 whilst simultaneously therewith, at a fluid or wetting agent metering unit 26, a measured amount of fluid is drawn from a main supply tank 78 by a piston 74, for subsequent delivery to a fluid container 82 simultaneously with the release of a measured charge of beads from the metering unit 16 into an auxiliary supply hopper 22. A fluid supply needle valve 104 is then opened and compressed air is simultaneously delivered to a first Venturi unit 92 which draws the fluid from the container 82 and delivers moisturized air to a second Venturi unit 106 where the measured quantity of beads is drawn from the auxiliary hopper 22 and delivered to a blending unit 30 (Figs. 8 and 9, not shown), where the beads and fluid are agitated prior to delivery to the mould 10, via a coupling unit 32 comprising an hydraulic cylinder reciprocable assembly of flexible bead delivery connecting tubes 150 and vacuum tubes 176. Beads are drawn into the mould cavities (194) (Fig. 3, not shown), by vacuum applied through porous plugs (208). The feed control circuit (Fig. 12, not shown), includes a time delay motor and switching mechanism (303) whereby a solenoid (305) is energized to release compressed air to the first Venturi unit 92 simultaneously with the denergizing of a pair of solenoids (315, 316) which action respectively actuates piston 74, via an air cylinder 70 to deliver fluid from pump 72 to container 82, and an air cylinder (52) (Fig. 4, not shown), which operates the metering unit 16 to deliver the measured charge of granules to the auxiliary hopper 22; the action of the first and second Venturi units 92 and 106 ceases when the solenoid (305) is de-energized by the time delay motor when the pair of solenoids (315 and 316) are energized respectively to draw a measured quantity of wetting agent into pump 72 and a measured quantity of beads into metering unit 16. The bead metering unit (16) (Figs. 4-7, not shown), comprises an elongated container (36), the capacity whereof is variable by inflatable rubber or plastics containers (60) and provided at upper and lower ends thereof with apertured valve plates (44, 46) for respective co-operation with similar stationary plates (38, 40), which plates (44, 46) are rotated by means of the air cylinder (52) via a reciprocated spindle (42) so that the apertures in each plate alternately are brought into and out of register respectively to take delivery of and to effect discharge of the measured quantity of beads. The blending unit (Figs. 8 and 9, not shown), comprises a stationary vertical cylindrical housing (120) provided in the base thereof with a constantly rotating horizontally extending bar (130) with upstanding vanes (132) and provided also with a longitudinally extending arcuate baffle plate (134); the blended beads collect in a radially extending housing (140) connecting to the delivery tubes (150).