GB2061219A - Apparatus for forming, filling, sealing and cartoning bags - Google Patents

Abstract

A form, fill, seal apparatus wherein individual filled and sealed bags are drawn into respective open-ended cartons, comprises a hollow mandrel (10) around which a web (11) of packaging material is formed into a tube (12) of rectangular cross-section, a bag retaining tube (16) located between a pair of transverse sealing jaws (15) and a pair of knives (17) for separating individual filled and sealed bags, a mechanism (13, 26) for intermittently feeding the tube downwardly and a reciprocating picker (19) for engaging the lower ends of the bags and guiding them into cartons (20) supplied by a conveyor. <IMAGE>

Description

SPECIFICATION Improvements in packaging apparatus It has long been known to produce bags filled with particulate material, such as tea or rice, by feeding a web of wrapping material downwardly over a hollow tube former, which forms the web into a longitudinally sealed tube, forming transverse seals at intervals in the tube, introducing a charge of the material to be packaged into the tube through the tube former between successive transverse seals and severing the tube at the transverse seals to form individual filled bags.

The normal practice has been to form the transverse seals by a pair of heated sealing dies which move towards one another in the transverse direction to form a seal, then move downwardly to draw the tube downwardly over the tube former, then separate and finally move upwardly to their original level, a filling being introduced into the tube after the formation of each transverse seal and the sealing dies carrying a cutter which separates each filled bag from its successor.

The individual bags are in some instances carried away from the bag forming and filling station by a conveyor to a further station at which the bags are transferred laterally into individual cartons.

It has recently been proposed to feed open-ended cartons individually into position beneath the tube former and to feed each bag individually into a carton by a picker which rises upwardly through the carton and then retracts to draw the bag down into the carton.

The necessity to impart vertical reciprocation to the relatively heavy sealing jaws tube downwardly over the tube former has been found an obstacle to running the apparatus at high speed. In addition, with certain packaging materials there is an undesirable tendency of the bags to bulge, particularly when filled with a heavy product such as rice, which can cause difficulty when the bags are drawn downwardly into the cartons.

The invention provides packaging apparatus comprising a vertical tube formerfor forming a web of wrapping material into a tube of rectangular cross section, a pair of transversely movable sealing jaws disposed at a fixed level beneath the lower end of the tube former, means for feeding a charge of particulate material to be packaged downwardly through the tube former after formation of each transverse seal by the sealing jaws, a bag retaining tube disposed beneath the sealing jaws and aligned with the tube former, a cutter beneath said tube for severing the tube into individual filled bags at the level of the transverse seals, a conveyor for feeding open-ended cartons in succession to a loading station beneath the cutter, a reciprocating picker for engaging the lower ends of the bags and guiding them into the cartons, and feed mechanism for engaging the outer portion of the tube surrounding the tube former and operative intermittently to feed the tube downwardly following completion of each transverse seal.

Preferably the picker is constituted by grippers which engage the tail of the severed transverse seal at the bottom of each bag. The feed mechanism is preferably constituted by a pair of suction belts, i.e.

porous belts to which suction is applied, which engage opposed faces of the tube. Alternatively conveyor belts, rotatable rollers or receiprocating clamps can be used.

If there is any resistance to the drawing action of the picker during introduction of a bag into a carton the picker may rupture the bottom seal of the bag with a consequential spillage of the contents. Such resistance to the drawing action of the picker may arise when an existing bulge in the bag becomes enlarged when the bag engages the mouth of the carton. Bulging of the bag is particularly prevalent when the bag is filled with a heavy type of product, e.g. rice. Resistance to the drawing action may also be encountered due to the friction arising between the bag and the inner walls of the carton. Furthermore, when using certain types of wrapping material there is a tendency for the material to stretch. When using such materials any resistance to the drawing action will tend to stretch the material resulting in a mis-shapen bag.

Preferably, therefore, the movement of the picker is so coordinated with the downward feed imparted to the tube by the suction belts or other feed mechanism that the wall of each bag is maintained in tension during transfer of the bag to the carton.

One embodiment of the invention is illustrated, by way of example, in the accompanying diagrammatic drawings, in which: Figure 1 is a side elevation; Figure2 is an end elevation; Figure 3 is a plan view; Figures 4-6 are sectional views on a larger scale illustrating successive stages in operation of the apparatus; Figure 7 is a downward continuation of Figure 1 showing mechanism situated below the break in Figure 1; and Figure 8 is a similar downward continuation of Figure 2.

The apparatus illustrate in the drawings includes a hollow mandrel 10 over which a web 11 of bag making material is fed from a reel 1 1A in the conventional way to form a tube 12 of rectangular cross section, a pair of suction belts 13 disposed adjacent opposite faces of the mandrel, a sealing element 14 for sealing the longitudinal seam ofthe tube, a pair of transverse sealing jaws 15 positioned below the mandrel and arranged to form transverse seams in the tube, a retaining tube 16 mounted below the jaws 15 and below this a pair of knives 17 for severing filled bags 18 from the tube.Below the cutter is a carton conveyor which transports cartons 20 in succession along support rails 18Ato a bag loading position to receive the filled bags, the cartons being open at the top and the bottom to allow passage of a pair of grippers 19.

Afilling spout 21 is provided above the mandrel 10 through which successive charges of the material to be packaged are fed in succession into the bags by any conventional form of feeder. As shown in Figure 2, a reserve 11 B of bag forming material 11 is formed between the mandrel 11 and the reel 11A.

The jaws 15 are mounted in slides 22 (Figure 2) and reciprocated by cam-operated links 23. The knives 17 are mounted in slides 24 and reciprocated by cam-operated links 25. The suction belts 13 are mounted on upper and lower rollers 26 (Figure 1) secured to spindles 27. The lower spindles 27 carry bevel gears 28 which mesh with bevel gears 29 on a shaft 30, which is driven by a belt 31 from a split shaft 32 (Figure 2), on which are mounted a clutch (not shown) and a gear33 meshing with a pinion 34 which engages a toothed quadrant 35 which is rocked about a pivot 36 by a cam-operated 37. Upon clockwise movement of the quadrant 35 movement is imparted to the belts 13 through the belt drive 31 and on the return stroke of the quadrant 35 the clutch freewheels so that no movement is imparted to the belts 13.

As shown most clearly in Figures 7 and 8, the grippers 19 are mounted on the upper end of a tube 38 mounted on a bracket 39, which is disposed in a casing 40 situated beneath the rails 18A and slidably mounted on a pair of rods 39A, 39B. The bracket 39 is connected by a link 41 to one arm of a bell crank 42 pivoted to a shaft 43. The other arm of the bell crank carries a follower 44 which engages the face of a cam 45.

The grippers 19 are maintained open by a spring 46 (Figure 6) disposed between the jaws of the grippers and are closed by engagement of a projec fion 47 on a member 48 with tailpieces 49 on the gripperjaws. The member 48 is slidably mounted in the tube 38 and is connected at its lower end to the piston of a double-acting air cylinder 50 (Figure 8).

Figure 4 shows the first part of a cycle of the apparatus in which a bag 18 has been formed and filled and is held in the bag retaining tube 16 by the jaws 15, which have formed a transverse seal in the tube 12, the seal priorto being severed, constituting the top seal of a filled bag and the base seal of the next succeeding bag. An open carton 20 has been transported to the bag-loading position and the grippers 19 are being moved upwardly by the cam 45 through the carton towards the base seal of the filled bag. At this stage feed of the product through the mandrel 10 into the partlyformed next succeeding bag may commence.

Upon completion of the upward movement of the gripper 19, the air cylinder 50 operates to raise the member 48 and cause the grippers 19 to close against the action ofthe spring 46 and nip the base seal of the filled bag as shown in Figure 5. The grippers are then lowered by the cam 45 to guide the filled bag into the carton 20.

As the grippers 19 commence their downward movement through the carton 20 the suction belts 13 commence operation which has a two-fold effect.

The belts 13 maintain the tension between the filled bag and the tube 12 of bag making material on the mandrel 10 thus prevent any tendency of the contents of the bag to form a bulge therein, and also feed a length of the material 11 downwardly over the mandrel 10 by an amount sufficient to form another bag. During continued movement ofthe grippers 7 and the suction belts 13 the filled bag is transferred into the open carton 20. Also during this movement the product continues to be fed through the mandrel 10 into the next bag.

The bag retaining tube 16 ensures that each filled bag will retain the shape corresponding to the interior of the carton 20.

When the filled bag has been transferred into the carton 20, the air cylinder 50 operates to move the member 48 downwardly in the tube 38 to withdraw the projection 47 from the tail piece 49 and allow the spring 46 to open the grippers 19.

The final part of the cycle is illustrated in Figure 6 which shows the filled bag inserted into the carton with the grippers 19 open and moved clear of the path of travel of the carton, the knives 17 have severed the filled bag from the next bag which is now positioned in the bag retaining tube 16, the jaws have moved inwardly to form another transverse seal in the tube 11, and the operation of the suction belts 13 has stopped. Priorto closing ofthejaws 15 the feeding of the product has also ceased. The cycle of operation is then repeated.

The primary feed of the tube is effected by the belts 13, the grippers 19 serving to guide the filled bags into the cartons 20 and maintaining tension in the walls of the bag during this operation.

As shown in Figures 3 and 8, the carton conveyor is constituted by a series of boxes, each constituted by a pair of side walls 51 pivoted at 52 to a bracket 53 secured to an annulus 54, and urged by springs (not shown) to position to engage and hold a carton 20.

Each side wall 51 has an arm 55 carrying a roller 56.

When the boxes reach carton feeding and carton dishcarge stations the rollers 56 are caused by a fixed cam (not shown) to open the side walls 51 against the action of the springs. The annulus 54 is supported between pairs of rollers 57 (Figure 8) and is rotated by a spur gear 58 which meshes with gear teeth 59 on the inner face of the annulus. The gear 58 is mounted on a shaft 60 which is rotated intermittently by a Geneva mechanism 61.

As shown in Figures 2 and 3 a stack of carbon blanks 62 is contained in a magazine 63 from which the blanks are removed in succession by a blade 64 secured to an arm 65 mounted on a shaft 66, which is movable to and fro and up and down in a pillar67 by cam mechanism (not shown). Upon downward movement of the shaft 66 the blade 64 enters the leading carton blank 62 in the magazine 63. The shaft 66 is then rotated anticlockwise as seen in Figure 3 to cause the blade 64 to transfer the blank to a waiting box at the carton feeding station of the carton conveyor. During this movement the blank moves between shaped guides 68 which erect the blank into an open-ended carton with longer flaps at the lower end out-turned and shorterflaps atthe lower end inturned. When the open-ended carton has been transferred to the box, the shaft 66 is raised to withdraw the blade 64 from the carton and is then rocked clockwise to return the blade 64 to position above the magazine 63.

After each carton has been filled with a bag it is carried by the carton conveyor in succession and in known mannerthrough a tamping station, carton closing and sealing stations and finally to the discharge station.

Claims (7)

1. Packaging apparatus comprising a vertical tube former for forming a web of wrapping material into a tube of rectangular cross section, a pair of transversely movable sealing jaws disposed at a fixed level beneath the lower end of the tube former, means for feeding a charge of particulate material to be packaged downwardly through the tube former after formation of each transverse seal by the sealing jaws, a bag retaining tube disposed beneath the sealing jaws and aligned with the tube former, a cutter beneath said tube for severing the tube into individual filled bags at the level of the transverse seals, a conveyor for feeding open-ended cartons in succession to a loading station beneath the cutter, a reciprocating picker for engaging the lower ends of the bags and guiding them into the cartons, and feed mechanism for engaging the outer portion of the tube surrounding the tube former and operative intermittently to feed the tube downwardly following completion of each transverse seal.

2. Packaging apparatus according to claim 1, wherein the picker is constituted by a pair of gripper jaws wich engage the tail of the transverse seal at the bottom of each bag.

3. Packaging apparatus according to claim 1, wherein the feed mechanism is constituted by a pair of suction belts which engage opposed faces of the belt.

4. Packaging apparatus according to claim 1, wherein the movement of the picker is so coordinated with the downward feed as to maintain the wall of each bag in tension during transfer of the bag to the carton.

5. Packaging apparatus according to claim 1, wherein the conveyor comprises a series of cartonreceiving boxes mounted on an intermittently rotating support and means for transferring carton blanks in succession from a magazine to the boxes at a carton feeding station and erecting the blanks into open-ended cartons during the transfer.

6. Packaging apparatus according to claim 2, wherein the picker includes a spring for urging the gripper jaws to closed position and a reciprocating member which coacts with tails of the gripper jaws to open the jaws against the action of the spring.

7. Packaging apparatus according to claim 1, substantially as described herein with reference to the accompanying drawings.