NZ261919A - Forming and filling an interconnected series of reclosable bags, bag bottoms suspended on support rails and conveyed through charging, sealing and severing stations - Google Patents

Description

New Zealand No. International No. 261919 TO BE ENTERED AFTER ACCEPTANCE AND PUBLICATION Priority dates: 23.02.1993; Complete Specification Filed: 21.02.1994 Classification:^) B65B43/12; B65D33/24.34; B65D75/42; B31B27/00 Publication date: 27 April 1998 Journal No.: 1427 NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION Title of Invention: Interconnected plastic bags charging apparatus and method Name, address and nationality of applicant(s) as in international application form: MINIGRIP FLEXIBLE PACKAGING LIMITED, a New Zealand company of 27 Ross Reid Place, East Tamaki, Auckland, New Zealand WO W/19250 2619,19 TITLE: INTERCONNECTED PLASTIC BAGS CHARGING APPARATUS AND METHOD TECHNICAL FIELD This invention relates to a series of interconnected plastics bags incorporating recloseable elements and an apparatus and method for the automatic charging and sealing thereof. In particular the invention relates to such a series of bags adapted for bottom filling and which are linked by a continuous strip adapted to support the bags during a charging process and provide automatic separation following the charging and sealing thereof.

BACKGROUND ART Plastic bags incorporating recloseablc elements including bags interconnected in a series to assist automatic charging are well known. Also various apparatus is available and known for the automatic charging of such interconnected bags. US Patents, 4,665,552, 4630311, 4515962 relate to such interconnected bags and charging apparatus. A problem can arise in 15 charging such bags with, in particular, detritus or similar fine ground matter from the top as some of the charge may lodge in or on the recloseable elements hindering their operation. A further problem can be that with such a recloseable bag evidence of tampering, such an unauthorised access via the recloseable elements, is not provided for. An object of this invention is to provide a series of interconnected bags which it is envisaged will overcome 20 or at least alleviate the aforesaid problems. Further, it is envisaged that the associated charging apparatus and method will provide a particularly effective way of achieving these desired objects.

DISCLOSURE OF INVENTION According to a first aspect of this invention there is provided a series of bottom opened interconnected bags formed from plastic film, having engaged recloseable elements adjacent what, following sealing of a bag bottom, will become a top of the bag, a continuous strip interconnecting the bags along bottom opening defining extremities of opposing sides of the bags, and at least one strip including a support rail by which the bags in a bottom uppermost 30 and open mode can be supported during charging: RECEIVED Boi2spcc,298 Intellectual Properly Office 1 7 FFR 1SS8 of New Zealand WO 94/192311 PCT/NZ94/00012 it 26191 9 2 V the bags having side edges formed by heat sealing and severing to separate the bags from one another except for the continuous strip or strips, the edge forming seals being disposed transversely of the continuous strip or strips and the recloseable elements, the edge forming seals also sealing the edges of the bags between the recloseable elements and the 5 adjacent fold of the plastic film.

According to a second aspect of this invention there is provided a method of manufacturing a series of bottom opened interconnected bags having engageable recloseable elements comprising the steps of blow forming a tube of parent bag forming material incorporating recloseable elements adjacent what will become a top of the bags and, substantially opposite 10 the recloseable elements and bordering what will become the bottom of the bags, a section which will form strip connecting the bags, engaging the recloseable elements together either before or after slitting the tube longitudinally along the connecting strips forming section to form a connecting strip to each side thereof, at least one strip being provided with a support rail from which the bags can be suspended bottom uppermost and applying at bag forming 15 intervals transversely disposed heat seals and associated severing extending across the parent material except for the connecting strips the edge forming seals also sealing the edges of the bags between the recloseable elements and the adjacent fold of the bag forming material.

According to a third aspect of this invention there is provided a method of charging a series 20 of interconnected bags as described in the above paragraphs comprising the steps of advancing the series of bags through a charging station, at which the bottom of each bag is opened and a charge inserted, to a sealing station at which the bottoms of the bags are sealed and then transporting the bags to severing means and severing the bags from the interconnecting strip or strips.

BRIEF DESCRIPTION OF THE DRAWINGS Fig 1 is a side view, partly schematic, of three interconnected bags (representing a continuous series of such bags) formed from a parent tube of plastics film material, and Fig 2 is a cross-sectional view of a bag depicted in Fig 1, and 30 Fig 3 is a side view of a series of bags being conveyed through a charging apparatus which includes a charging station, sealing means and severing means, and , RECEIVED D<M2spec.298 Intalleciunl Property Orrice 1 7 FFR 1338 of i lew Zealand WO 94/19230 PCT/NZ94AM012 261919 Fig 4 and 5 are an end view, in the direction of arrow A on Fig 3, and a plan view respectively of the apparatus of Fig 3, and Fig 6 is a side view of the charging station, and Fig 7 is a plan view of the charging station with opening arms thereof near closed, and 5 Fig 8 is a similar view to Fig 7 showing the opening arms open, and Figs 9 and 10 are an end view and a perspective view of the opening arms and their means of engaging and supporting bags.

BEST MODE FOR CARRYING OUT THE INVENTION A series of interconnected bags 3 are preferably fabricated from a parent film tube 5 of 10 blown plastics film materials. Preferably the tube film material 5 integrally incorporates recloseable profiles 6a and 6b and integral support rails 7 although it is envisaged the support rails 7 may be added later. With folding or collapsing of the tube material 5 into a substantially two layered band, as depicted in Figs 1 and 2, the recloseable profile 6a and 6b are engaged with one another. The profiles 6a and 6b may be of any required known form 15 comprising basically a male element 6a re-engageable within a female element 6b. The folding of the tube film material 5 provides that the recloseable profile 6a and 6b are adjacently set in from one fold 8. As will be apparent from the following description eventually the recloseable profiles 6a and 6b and the associated section of the film material 5 forming fold 8 will become the tops 9 of bags 3.

B012spcc.29H , RECEIVED Intollccluni Propariy Office f 7 FFR 1958 of New Zealand WO 94/19250 PCT/NZ94/00012 4 The support rails 7 are disposed adjacent the opposing "fold" 10 of the tube material 5. More particularly, following blow forming and as depicted the tube film 5 is longitudinally slit on "fold" line 10 between the support rails 7. This provides open bottoms 11 enabling 5 access to the individual bags 3. The slitting of fold 10 also forms interconnecting strips 12, one associated with each rail 7, and which following formation of the individual bags 3 as hereinafter described connect the bags 3 in a series as depicted.

At required bag 3 forming spacings transversely disposed heat seals 13 and associated severing cuts 14 are applied to the parent film 5 to form the side edges 15 of the bags 3 and separate, save for the connecting strips 12, the bags 3 from one another. The seals 13 and cuts 14 extend transversely in from the top 9 forming fold 8 of the film material 5 and terminate at the strips 12. More particularly, the seals 13 and cuts 14 terminate marginally beyond an intended bottom, represented by line 16 on Fig 1, of the bags 3. As described hereinafter following charging of the bags a bottom closing seal 17 is formed adjacent the bottom line 16 and the bags 3 severed from the strips 12. The severing is along line 16 as to intersect with cuts 14 thereby providing for the separation of the bags 3 from one another and the strips 12.

The side edge seals 13 extend transversely across the recloseable profiles 6a and 6b and the associated folded section of the film material 5 forming the tops 8. Thus the recloseable profiles 6a and 6b are sealed-ofFby the folded top 8 and the seals 13. This provides that in a completed bag 3 the folded top 8 must be cut to access the recloseable profiles 6a and 6b thereby providing security against tampering.

Thus a series of bags 3 are provided interconnected by strips 12 extending along what will become the bottom of the bags 3. Each strip 12 carries a support rail 7 the purpose of which is to support the series of bags 3 on tracking means 18 extending through a charging and sealing apparatus as depicted in Figs 3-5 inclusively and now more particularly described.

The series of bags,. 3 are conveyed through the charging and sealing apparatus in the direction of arrow B on Fig 3. The bags 3 are supported bottom uppermost by rails 7 seating over tracking means 18. Preferably tracking means 18 is formed by a pair of parallel series of adjacently spaced apart rollers 19 mounted on vertically disposed axis, each roller SUBSTITUTE SHEET WO 94/19250 PCT/NZ94/00012 19 incorporating at a lower end thereof an annular rib 20 on which the rails 7 rest. The bags 3 are conveyed to a charging station 21 at which the rails 7 slide into and are gripped by opening arms 22. As depicted in Fig 8, arms 22 are operable by a suitable mechanism 23 to extend laterally to bottom opaii individual bags 3 in readiness for charging in known manner, 5 for example, from a chute (depicted schematically by ring 24 on Fig 5) disposed above charging station 21. A maximum charge volume is represented by line 32 on Fig 1. Following charging bags 3 are conveyed along tracking means 18 to a sealing apparatus 25. Sealing apparatus 25 preferably comprises a pair of laterally positioned and operative heated bars 26 which can be impinged inwardly onto the bags 3 to form the bottom seal 17 as 10 described above. Thereafter the bags 3 are conveyed to a severing apparatus comprising a horizontally extending blade 29 disposed to intersect the bags on line 16 to sever the strips 12 from the bags 3 as depicted at arrow 30. Preferably the bags 3 are driven along the tracking means 18 by a pair of continuous belts 31 disposed to either side of the bags 3 to impinge the bags therebetween and preferably extending from the sealing means 25 through 15 to the severing blade 29. An electric motor 27 and associated drive train 28 are provided to rotate the belts 31 to draw the bags 3 through the apparatus.

SUBSTITUTE SHEET PCT/NZ94/TO012 261919

Claims (7)

1. A series of bottom opened interconnected bags formed from plastic film, having 5 engaged recloseable elements adjacent what, following sealing of a bag bottom, will become a top of the bag, a continuous strip interconnecting the bags along bottom opening defining extremities of opposing sides of the bags, and at least one strip including a support rail by which the bags in a bottom uppermost and open mode can be supported during charging; 10 from one another except for the continuous strip or strips, the edge forming seals being disposed transversely of the continuous strip or strips and the recloseable elements, the edge forming seals also sealing the edges of the bags between the recloseable elements and the adjacent fold of the plastic film.

2. A series of bags as claimed in claim 1 wherein the or each support rails is integrally 15 moulded with the associated strip.

3. A series of bags substantially as herein described with reference to the accompanying drawings.

4. A method of manufacturing a series of bottom opened interconnected bags having engageable recloseable elements comprising the steps of blow forming a tube of parent bag 20 forming material incorporating recloseable elements adjacent what will become a top of the bags and, substantially opposite the recloseable elements and bordering what will become the bottoms of the bags, a section which will form strips connecting the bags, engaging the recloseable elements together either before or after slitting the tube longitudinally along the connecting strips forming section to form a connecting strip to each side thereof, at least one 25 strip being provided with a support rail from which the bags can be suspended bottom uppermost and applying at bag forming intervals transversely disposed heat seals and associated severing across the parent material except for the connecting strips, the edge forming seals also sealing the edges of the bags between the recloseable elements and the adjacent fold of the bag forming material. the bags having side edges formed by heat sealing and severing to separate the bags R d c ij | v I! D i 7 FFR 1338 of New Zealand WO 94/19250 PCT/NZ94AXM12 ~ b.w i 91 9 *

5. A method of manufacturing a series of bottom opened, interconnected bags having engageable recloseable elements substantially as herein described with reference to the accompanying drawings.

6. A method of charging a series of interconnected bags as claimed in any one of claims 5 1 to 3 comprising the steps of advancing the series of bags through a charging station, at which the bottom of each bag is opened and a charge inserted, to a sealing station at which the bottoms of the bags are sealed and then transporting the bags to severing means and severing the bags from the interconnecting strip or strips.

7. A method of charging a series of interconnected bags substantially as herein 10 described with reference to the accompanying drawings. END OF CLAIMS James/ U Piper & Attorneys For: Minigrip Flexib k packaging Limited nncnivHD B012.spec.29K frltelUviurtl IVupei'ty Offlee J 7 FT^ 13J8 of New Zealand