Patent GB-799592-A (GB)
Title: Improvements in or relating to molding apparatus
Inventor: HOLLY HARRY HAROLD
IPC: A22C7/00
Filed: 1956-06-23
Abstract: 799,592. Removing articles from moulds. HOLLYMATIC CORPORATION. June 23, 1956, No. 19528/556. Class 87(2). Apparatus for moulding portions of plastic material to form articles such as meat patties by filling a mould opening with plastic material such as ground meat includes apparatus for removing a portion from the mould opening comprising (i) means for contacting the portion to dislodge it, (ii) means for withdrawing the contacting means, (iii) means for preventing air flow through the contacting means as they approach the portion, (iv) means for venting air on completion of the approach. The patty is moulded in an opening 15a in a mould plate 15 which is interchangeable with other mould plates having differently shaped openings. Feeding. The ground meat or fish is contained in a hopper 12 and is fed to the mould opening by two oscillating feeders 18, 19 with ram portions 18a, 19a, Fig. 2. Figs. 1 and 2 show the mould plate 15 retracted and the feed rams nearest the mould opening. A lever 22 is oscillated by a motor drive, (not shown) and in moving anti-clockwise engages a flange 34a on a plate 34 attached to a gear sector 35, rotating them both anti-clockwise. The gear sector 35 meshes with a gear sector 42 on the shaft 20 on which the feeder 18 is secured, first by a smaller radius segment 35b engaging a larger radius segment 42b and then by a larger radius segment 35a engaging a smaller radius segment 42a. The feeders 18, 19 are geared together and both are rotated away from the mould opening with a slow movement followed by a fast. For ease of access the shaft 21 on which the feeder 19 is secured, and its gear wheel, are held in place by a disc 45 on the shaft 20. The gearing is protected by a shrouding 46 hinged at 47. Anticlockwise movement of the lever 22 also slides the mould plate 15 to the position, Fig. 4, where the moulded patty is removed from the mould opening, the movement being transmitted through a link 50 attached to an axle 53 on the mould plate. Clockwise movement of the lever 22 is transmitted to the gear sector 35 through a flat coiled spring, (not shown), in a casing 37, with one end fixed to the shaft 23 to which the lever 22 is attached, the casing being rotatable on the shaft. The casing is linked to the sector 35 through a bolt 40. At the beginning of its clockwise movement the lever 22 is tied to the plate 34 by a weighted catch 48, rotatable about a pin 49 on the lever and engaging the top of the flange 34a by a hook 48a so that the gear sector 42 is positively driven for the first movement of the feeders 18, 19 towards the mould opening. When the lever 22 passes an approximately vertical position the catch 48 disengages and the drive is then through the spring in the casing 37, allowing the rams 18a, 19a to yield to excessive resistance by the material in the hopper 12. The spring tension may be adjusted by turning the bolt 40 and by selecting one of a number of holes 37a, in the casing 37, into which a pin 39 is screwed to locate one end of the bolt 40. Delivery. A knockout ring 55 is shaped like an inverted cup, Fig. 4, so that the edge of the moulded patty only is struck and it is knocked out of the mould opening without its edges becoming jagged. The knockout ring is attached to a holder 54 by a nut and bolt assembly 56 and is first raised as the mould plate 15 moves to the feeding position by the movement of toggle links 57a, 57b, the link 57b being pivoted on the axle 53 and raising the holder 54 as it swings. A catch 58 drops behind a flange 54b on the holder and the knockout ring is therefore retained in its raised position, where also a tension spring 60 is extended between a pin on the link 57b and an anchorage on the holder 54. The spring 60 and gravity combine to cause the knockout ring 55 to descend and to apply a sharp rap to the material in the mould opening when the catch 58 is released, which occurs when the mould plate 15 has moved from beneath the hopper 12 and the upper end of the link 57a engages the end of the catch. The shock is cushioned by a rubber button 59. During the outward movement of the mould plate a thin sheet of paper is taken from a stack 65 and applied to the bottom of the material in the mould opening. The blow from the knockout ring is controlled to prevent the edges 55a from penetrating the material too deeply, by air trapped in the ring. To prevent a partial vacuum from tending to hold back the moulded patty the ring is vented at 55c, the vents being covered with a flexible sheet 71 which bends and partially uncovers the vents, as shown in dotted lines, Fig. 4, during the withdrawal of the ring from the opening 15a.