Patent GB-628515-A (GB)
Title: Improvements in or relating to the packaging of substances, in tablet or other form, in strips of material
IPC: B65B9/06
Filed: 1947-06-03
Abstract: 628,515. Packaging tablets &c. MORGENSTERN, K. D., and WHITE, F. June 3,1947, No. 14673. [Class 94(i)] Apparatus for packaging substance in tablet or other form, in strip material, comprises means for longitudinally feeding a strip of the material folded over longitudinally, means for feeding units of the substance periodically into the channel formed by the folded strip, means for effecting a preliminary seal of the channel walls together behind each unit before the strip is fed beyond the position at which the unit was fed thereinto, and means for effecting a final seal of the channel walls together so as to complete a pocket for each unit after the strip has been fed beyond the said position. In the construction shown, applied to the packaging of tablets, a strip 1 of packaging material fed over a spring-loaded tensioning-roller (not shown) from a supply reel, is folded about its longitudinal axis into channel form by an appropriately-shaped, folding-plate 13, Fig. 5. The channelled strip is fed between jaws 7, 8 by rollers 5, 5<SP>1</SP> which are in toothed engagement and are rotated intermittently by a Geneva mechanism 40 associated with roller 5 and a gear 58 driven via a gear train 55, 54 and a worm 52 coupled to a main driving electric-motor (not shown). A hopper 16 mounted above, but tangentially disposed with respect to the jaws 7, 8, is provided with a chute 3 leading from the periphery of the base 16a of the chute 16 so that it extends between the jaws 7, 8 and into the channelled packing strip. The jaw 7 is pivotally mounted by a bell-crank 20, 36 on a rod 22 carried by the machine frame and is outwardly movable against a strong spring 39 under intermittent movement of the arm 36 of the bell crank. This movement is derived from the rotation of a gear 34 which is coupled through a gear train to the worm 52 and carries a portion 35 having a saw-toothed profile which engages a corresponding saw-toothed profile on a part 37 carried by the arm 36. An arm 21 carrying the jaw 8 is normally fixed relative to the machine frame, but may be swung outwards and downwards after unscrewing securing-bolts (not shown), in order to provide access to the channelled packing strip. The jaws 7, 8 are provided with electric heating-elements 61 and projections 9, 10 which in the closed position of the jaws provide successive spot seals near the base of the channelled strip. The feed rollers 5, 5<SP>1</SP> have heating elements 62 in order that they may seal the packing strip around the tablet. The rollers have cut-away portions 6 to receive the tablet and which cause the seal to extend in inverted U formation around and above the tablet between the spot seals on respective sides thereof. The hopper 16 includes a distributing dome 19 which guides the tablets into recesses formed between the teeth 18 of a toothed wheel 17 and the base and periphery of the hopper 16. The wheel 17 and distributing dome are coupled by suitable respective gear trains to the worm 52 so that they rotate in opposite directions. The feed rollers 5, 51 are serrated as shown, but may be provided with means to emboss the packing strip and with means to stamp a line of perforations. The circuits of the heating elements 61, 62 are provided with switches which operate intermittently according to the temperature of the elements. The teeth 18 may be arranged to accommodate two or more tablets either superposed or radially or circumferentially adjacent. The apparatus may be adapted for packing liquids and powdered substances. Operation. The channelled packing strip is fed forwards in intermittent steps by the feed rollers 5, 5<SP>1</SP>. During the periods of rest, the jaws 7, 8 close and form a spot seal and a tablet between the two teeth of the wheel 17 which are at that instant in register with the chute 3, is delivered by the chute to the packing strip in between the spot seal just formed and the spot seal previously formed. A cover plate 20 is provided above the wheel 17 in the regions of the chute 3 to prevent more than one tablet being fed at one time. The plate 20 is ramp-like in form and is relatively thick at its central portion in order that the tablets may ride over it, and it may be vertically adjustable to accommodate tablets of different sizes. A shutter may be provided for automatically closing the chute 3 in the event of a tablet being crushed by the rollers and may be arranged to cause the main driving-motor to be switched off. The passage of the tablets down the chute is facilitated by the jarring of the machine parts brought about by the operation of the saw-toothed members 34, 37. This action may be supplemented by means of an air jet provided by a pump the moving parts of which are coupled to the arm 36. The packing strip is then fed past spring members 47, 48 which press together the channel sides, and then through the feed rollers 5, 6 which complete the seal. The strip may then be wound on to a reel (not shown) or means may be provided for cutting the strip into lengths. The two tablet-locating spot seals may alternatively be formed by rollers and may alternatively be in the form of a semicircular seal passing underneath the tablet. In a further alternative arrangement the feed rollers may be unheated, the main sealing means then being carried by extensions of the jaws 7, 8.