NZ244262A - Apparatus for opening a gussetted bag having guides to accommodate v shapes of bags, and associated clamps which open out the v shapes - Google Patents

Description

2 442 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION AFTER PROVISIONAL NO: 244262 DATED; 8 SEPTEMBER 1992 METHODS AND APPARATUS FOR BAG OPENING WE, TRANSPAK INDUSTRIES LIMITED, of 23-25 Porana Road, Glenfield, Auckland, New Zealand, a New Zealand company, hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 244-262 The present invention relates to methods and apparatus for bag opening.

The term "bag" is used for simplicity in the present specification but is intended to cover all types of flexible containers having an opening through which the contents flow to fill the container and includes a length of material, such as a plastics film, prior to being formed into a bag.

Typically, and as described hereinafter, the container will be of a plastics material but this of course is given by way of example only.

Bags, and in particular, plastic bags, are used extensively throughout the world for packaging of various types of products including food products.

In the case of food products, it is important to minimise the possibility of the product being contaminated particularly by its contact with the human operator who is attending to the filling of the bag with the food product.

In the case of a plastic bag, the operator needs to open up the bag to allow the food product to flew into it and it is this operation which offers a major £44-262 possibility of contamination occurring by the fingers of the operator either coming into contact with the food, product itself or the operator's fingers encroaching within the bag and leaving bacteria inside the bag which will then be contacted by the food products.

There are some food products which are particularly susceptible to contamination, one such being mozzarella cheese. This is a "dead" cheese which does not have any natural organisms which in "live" cheese are able to combat foreign bacteria. Therefore, if any bacteria is allowed to be present within the bag when it is being filled with the mozzarella, which is flowable when hot but then solidifies as it cools, the packaged mozzarella will then provide a breeding ground for that bacteria and the mozzarella can rapidly become severely contaminated.

It is thus an object of the present invention to provide a method and apparatus for the opening of a bag which obviates problems inherent in such methods and apparatus to date, or at least will provide the public with a useful choice.

According to one aspect of the present invention, there is thus provided a method of opening a bag so as 244?^ _ 4 - to receive contents to be packaged therein, said method comprising:- (i) Providing opposed pairs of side walls along opposite edges of said bag so as to define at each edge a substantially "V" shape; (ii) Feeding each pair of said side walls on to a respective guide means to accommodate at least an interior portion of said "V" shape; (iii) Providing a clamping means associated with said guide means and feeding said side walls along said guide means so that exterior edges of said side walls are received within said clamping means; (iv) Operating said clamping means so as to clamp said exterior edges; and, (v) Operating said clamping means so as to separate respective portions clamping opposite exterior edges of each pair of said side walls to open out said bag.

According to a further aspect of the present invention, there is provided a method of opening a bag as immediately above-defined wherein said guide means comprises a movable member adapted to receive each of said exterior edges of said side walls and transfer same to said clamping means. 214262 According to a still further aspect of the present invention there is provided an apparatus for opening a bag comprising:- (i) Guide means comprising a pair of guide members adapted to accommodate at least the interior portions of respective "V" shapes defined by opposed pairs of side walls formed along respective edges of said bag; (ii) A clamping means associated with said guide means which is able to receive in respective portions thereof, and clamp, exterior edges of each of said side walls; and (iii) Separating means for separating opposed portions of said clamping means so as to open out said bag.

According to a still further aspect of the present invention there is provided an apparatus as immediately above-defined wherein said guide means comprises a movable member adapted to receive said exterior edges of said side walls and transfer same to said clamping means. , Further aspects of this invention which should be considered in all its novel aspects will become apparent from the following description given by way of example of possible embodiments thereof and wherein; 2442.62 Figure 1: shows very diagrammatically a bag being fed onto the guide means of one possible embodiment of the invention; Figure 2: shows very diagrammatically a cross-sectional view of the guide means and clamping assembly of one possible embodiment of the invention and with the clamping means in its open position; Figure 3: shows a view of Figure 2 but with the clamping means in its clamped position; Figure 4: shows a view of Figure 3 but with the clamping means in its separated position; Figure 5: shows very diagrammatically an alternative embodiment of the invention; Figure 6; shows very diagrammatically a cross-sectional view of the clamping assembly of Figure 5; Figure 7: shows very diagrammatically a view of the embodiment of Figure 5 as the movable bag former unciamps and descends along the film path; 2442.62 shows very diagrammatically the next stage of the operation of Figure 7 where the bag is sealed and cut; shows very diagrammatically the bag being opened out; and, shows the bag clamp assembly portions again moving together.

Referring now to the accompanying drawings, and * firstly with regard to Figures 1 to 4, a bag is referenced generally by arrow 1 and is shown having on each side a pair of side walls 2, typically being those which are present in a gussetted plastics film bag.

The side walls 2 are shown defining on each side of the bag 1 an essentially "V" shape. An operator's hands are shown in Figure 1 feeding the spaced apart side walls 2 onto respective guide members 4 with the bag opening 3 provided between the opposed guide members 4.

Each of the guide members 4 is shown by way of example.as having a finger 5 which fits into at least an inner portion of each of the "V" shapes. The lower edge 6 of each of the fingers 5 may be tapered so as to facilitate the fitting of the "V" shapes over the fingers 5. The operator is now able to feed the bag 1 along the guide members 4 and it is seen that this Figure 8: Figure 9: Figure 10; 244262 operation avoids any need for the operator's fingers to approach the opening 3 thus risking any bacteria from the operator's fingers being received within the bag 1. The exterior edges 7 of side walls 2 are then shown in Figure 2 being received between the respective open pairs of members 8 and 9 of a clamping assembly 10.

Once properly positioned between the respective members 8 and 9, at least the members 9 in this example are shown movable in a direction indicated by arrows A so as to clamp the exterior edges 7. In one possible embodiment the clamping forces may be provided by hydraulic or pneumatic means. An air bag assembly may be used in one possible embodiment.

It is also mentioned that appropriate control means are suitably incorporated, so as to ensure that each of the exterior edges 7 is properly accommodated between respective clamping portions and is properly clamped.

Suitable limit switches, photo-electric means and pressure detection means may all be suitable for such control purposes, but any suitable control means may be utilised, as would be apparent to those skilled in the engineering arts.

In the position shown in Figure 3 the opposite exterior edges 7 are now clamped between respective pairs of members 8 and 9. Then in Figure 4 the respective pairs of members 8 and 9 are shown moving apart in a direction indicated by arrows B to expand the bag opening 3 to its full extent ready to receive contents to fill the bag 1. This embodiment of the invention would suitably then include appropriate means for the bag opening 3 being closed up and sealed in any suitable manner.

It will be seen that apart from the initial feeding by the operator of the bag onto the guide members 4, there has been no human involvement with the operation and that the initial operation was also able to avoid any danger of contamination entering the bag 1.

A further embodiment of the present invention is illustrated very diagrammatically in Figures 5 to 10.

In this embodiment a gussetted film 11 is shown provided on a roll 12 and fed around a roller 13. The free end of the film is shown with its opening 14 positioned within a bag forming assembly 15. In Figure 5 the bag forming assembly 15 is shown associated with a bag sealing and cutting assembly 16 and a bag clamping assembly 17.

The bag forming assembly 15 is shown provided with opposed guide members 18 conforming to the "V" shapes to 244262 be formed along the opposed edges of film 11 at its top edge.

The clamping head assembly 17 is shown receiving the top edge of the film about its opening 14, from the former assembly 15, so that the exterior corner edges 7* can then be clamped by the movable clamping members 20 against other clamping members 21, as shown in Figure 6.

Then in Figure 7 the bag forming apparatus 15 is * shown unclamping itself from the top of the film and retracting along the film path in the direction of arrow C beyond the bag sealing and cutting assembly 16. That assembly 16 would need to be openable to allow for the passage of the forming assembly 15. .5 In Figure 8, arrows D indicate the sealing and cutting of the film by the movement of the sealing and cutting members of the assembly 16 so as to form the bottom edge of the bag 1* (see Figure 9) .

The bag 1* will now be independent of the film 11, the free end of which will now be held by the bag forming assembly 15 and/or the sealing and cutting assembly 16.

Z44-Z62.

As shown in Figure 9 the bag 1 can now be opened out which may be done in the position shown in Figure 8 or by the swinging away of the clamping assembly 17 to a separate bag opening and product filling station.

In Figure 9 the opening out of the bag clamping members 20, 21 in a direction indicated by arrows E is shown providing the expanded bag opening 3^".

The product can then be loaded into the bag 1^. Again suitable control means may be provided so as to confirm that the exterior side wall edges 7 are all properly held by the clamping assembly 17 before the operational sequence is allowed to continue so avoiding any problems with any attempt to fill an only partly opened bag 1^".

Once the bag 1* has been filled with product, clamping members 20, 21 may be released, dropping the filled bag 1* into a container for further processing, such as in a vacuum chamber.

In figure 10, prior to the filled bag l1 being released, the clamping members 20, 21 are shown having been brought together ag?.in in the direction of arrows F. 244-262 It is envisaged that the sealing and cutting assembly 16 and the bag forming assembly 15 may be combined together so that in this embodiment, once a bag 1^" has been formed, filled and removed, the free edge of the film 11 will be taken up to the clamping assembly 17 by the combined assembly 15, 16 which will then return to the position shown in Figure 7 ready for its sealing and cutting operation to form the bottom of the next bag i1.

In the present embodiment, as mentioned previously, the bag forming assembly 15 will need to be able to traverse past the sealing and cutting assembly 16 as well as to have means for holding the free end of the film 11 in taking it to the clamping head 17. For this purpose the bag forming assemblies may suitably be provided by hydraulic, pneumatic or other clamping means able to clamp the free end of the film 11 about the members 18.

Where in the foregoing description reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to possible embodiments 24-4-262 thereof it is to be understood that modifications or improvements may be made thereto without departing from the scope of the invention as defined in the appended claims. 244262

Claims (13)

WHAT WE CLAIM IS:

1. A method of opening a bag so as to receive contents to be packaged therein, said method comprising:- (i) Providing opposed pairs of side walls along opposite edges of said bag so as to define at each edge a substantially "V" shape; (ii) Feeding each pair of said side walls on to a respective guide means to accommodate at least an interior portion of said "V" shape; (iii) Providing a clamping means associated with said guide means and feeding said side walls along said guide means so that exterior edges of said side walls are received within said clamping means; (iv) Operating said clamping means so as to clamp said exterior edges; and, (v) Operating said clamping means so as to separate respective portions clamping opposite exterior edges of each pair of said side walls to open out said bag.

2. A method of opening a bag as claimed in Claim 1 wherein said guide means comprises a movable member adapted to receive each of said exterior edges of said side walls and transfer same to said clamping means. - 15 - ZU2 61 10 15 20 25

3. A method as claimed in Claim 1 or Claim 2 wherein said bag is initially in the form of a plastics film, the free end of which is fed to a bag forming assembly including said guide means, said bag forming assembly being movable so as to move said free end of the film to said clamping means.

4. A method as claimed in Claim 3 further providing sealing and cutting means operable so as to cut and seal said film in creating said bag.

5. A method of opening a bag substantially as herein described with reference to Figures 1 to 4 or 5 to 10 of the accompanying drawings.

6. An apparatus for opening a bag comprising:- (i) Guide means comprising a pair of guide members adapted to accommodate at least the interior portions of respective "V" shapes defined by opposed pairs of side walls formed along respective edges of said bag; (ii) A clamping means associated with said guide means which is able to receive in respective portions thereof, and clamp, exterior edges of each of said side walls; and (iii) Separating means for separating opposed portions of said clamping means so as to open out said bag.

7. An apparatus as claimed in Claim 6 wherein said guide means comprises a movable member adapted to 244262 - 16 - receive said exterior edges of said side walls and transfer same to said clamping means.

8. An apparatus as claimed in Claim 7 wherein said bag is initially in the form of a film and said apparatus includes sealing and cutting means adapted to engage with and cut and seal said film spaced apart from said free end in forming said bag.

9. An apparatus as claimed in Claim 7 wherein said guide means is movable with a sealing and cutting means adapted to engage with and cut and seal said film, spaced apart from said free end in forming said bag.

10. An apparatus as claimed in Claim 8 wherein said guide means is able to retract along the path of said film away from said free end so as to be beyond said sealing and cutting means.

11. An apparatus as claimed in any one of Claims 6 to 10 in which detecting means detect that said exterior edges are fully clamped between said respective portions of said clamping means.

12. An apparatus as claimed in any one of the preceding claims wherein said guide means each comprises a tapered finger. - 17 - 2442 6 Z

13. An apparatus for opening a bag substantially as herein described with reference to either of the embodiments of the invention of Figures 1 to 4 or 5 to 10 of the accompanying drawings. g/specs/500167COM(ld)