Reclosable package with zipper and slider in the fin seal

Abstract

The reclosable package or bag, typically formed by a horizontal form-fill-and-seal method wherein a single sheet of web forms a bottom wall and two side walls, includes a notched zipper so that the interlocking elements are not sealed within the side seals. Furthermore, the method to manufacture the package or bag uses a driven band, band sealer to decrease the drag induced to the film by the zipper. An encoder is used to send a signal to the stepper motors to match the film speed. Band sealers are used to seal the zipper onto a continuously moving web. The band prevents the film from sticking to the seal bars.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a reclosable package or bag, and a method of manufacture thereof, wherein the zipper and slider are in the fin seal.

2. Description of the Prior Art

The prior art includes several reclosable packages or bags wherein the zipper is placed in or near the fin seal. This prior art includes U.S. patent application Ser. No. 11/054,032 entitled “HFFS Slider Bags with Zipper in Fin Seal” filed on Feb. 9, 2005 by Owen and McCracken. Moreover, the method of manufacture disclosed in U.S. Pat. No. 6,185,907 entitled “Horizontal Form-Fill-And-Seal Machine with Zipper Attachment” can be applied to similar reclosable packages or bags.

Similar methods for forming reclosable packages or bags are found in U.S. Pat. No. 4,277,241 entitled “Apparatus for Forming Bags of Thermoplastic Material” issued on Jul. 7, 1981.

While these packages and methods have been found to be satisfactory for their intended purpose, further improvements in reclosable packages are sought, particularly for increasing the ease of removal of the header of the package.

OBJECTS AND SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a reclosable package for products, wherein the ease of removal of the header is increased.

This and other advantages are achieved by incorporating a notched zipper profile into a package or bag manufactured by a horizontal form-fill-and-seal process wherein the package or bag includes a bottom wall and two side walls formed by folding a single sheet of web or film. Similarly, the method to manufacture the package or bag uses a driven band, band sealer to decrease the drag induced to the film by the zipper. An encoder is used to send a signal to the stepper motors to match the film speed. Band sealers are used to seal the zipper onto a continuously moving web. The band prevents the film from sticking to the seal bars.

DESCRIPTION OF THE DRAWINGS

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

FIG. 1 is a front plan view of the reclosable package or bag of the present invention, with the fin seal portion folded down to be flush with the remainder of the reclosable package or bag, further indicating the direction of travel of the film during the manufacturing process.

FIG. 2 is a cross-sectional view along plane 2-2 of FIG. 1.

FIG. 3 is a perspective view of the reclosable package or bag of the present invention, shown with the fin seal portion perpendicular to the remainder of the package or bag and the removable header in place.

FIG. 4 is a perspective view of the reclosable package or bag of the present invention, shown with the header removed and the zipper exposed.

FIG. 5 is a perspective view of the reclosable package or bag of the present invention, shown with the header removed and the zipper open to expose the contents thereof.

FIG. 6 is a perspective view of the manufacturing apparatus for the reclosable package or bag of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings in detail wherein like numerals indicate like elements throughout the several views, one sees that FIGS. 1 and 2 disclose the reclosable package or bag 10 of the present invention. Package 10 includes a single sheet of web or film 12 with lower fold 14 and upper fold 19 forming the respective bottom and top of the package. Front portion 16 of web or film 12 extends from the bottom fold to the first edge 17 of the web or film 12. Rear portion 18 of web 12 extends upwardly from lower fold 14 to upper fold 19 to form the rear wall of the package 10 (or alternatively, the bottom wall as shown in the orientation of FIGS. 3-5). Portion 21 of web 12 extends downwardly (in the orientation of FIG. 2) from upper fold 19 to interior fold 23 and then extends to second edge 25. First edge 17 and second edge 25 are joined by longitudinal fin seal 24. First and second side seals 20, 22 are formed proximate to the sides between front portion 16 and rear portion 18 thereby forming the sides of the package 10. Likewise, the distal ends of front portion 16 and rear portion 18 are sealed together by top fin seal 24 to form the top of package 10. As shown in the orientation of FIGS. 3-5, front portion 16 and portion 21 form first and second side walls of the package, while rear portion 18 forms the bottom of the package.

Folds 14, 19 are typically formed as a longitudinal or machine direction fold as the edges of the traveling web are brought together to form fin seal 24. Web 12 is typically formed from polymeric material, such as polyethylene or polypropylene, or other similar materials as known to those skilled in the art.

As shown in FIGS. 1 and 2, fin seal 24 can be folded over to be adjacent with upper fold 19. However, as shown in FIGS. 3-5, when package or bag 10 is filled with contents, fin seal 24 may project generally perpendicular to rear portion 18.

Zipper 30 includes first profile 32 and second profile 34. First profile 32 includes first flange 36 and first interlocking element 40. Likewise, second profile 34 includes second flange 38 and second interlocking element 42. Zipper 30 further includes slider 44 which operates in a conventional way in that slider 44 is mounted on first and second profiles 32, 34. Movement of slider 44 in an opening direction separates first and second interlocking elements 40, 42 from each other. Movement of slider 44 in a closing direction, opposite to the opening direction, interlocks first and second interlocking elements 40, 42.

First notch 50 and second notch 52 are formed at the ends of zipper 30 so that first lower portion 54 of first and second flanges 36, 38 has no interlocking elements immediately thereover and second lower portion of first and second flanges 36, 38 likewise has no interlocking elements immediately thereover.

First lower portion 54 of first and second flanges 36, 38 extends into side seal 20 and are sealed therewith and to each other. Second lower portion 56 of first and second flanges 36, 38 extends into second side seal 22 and are sealed therewith and to each other. The formation of first and second notches 50, 52 prevents the first and second interlocking elements 40, 42 from extending into first and second side seals 20, 22.

The lower portion of first flange 36 is sealed to front portion 16 along first flange seal 60 while the lower portion of second flange 38 is sealed to rear portion 18 along second flange seal 62.

First line of weakness 66 is formed on front portion 16 immediately above first flange seal 60. Likewise, second line of weakness 68 is formed on rear portion 18 immediately above second flange seal 62. First and second lines of weakness 66, 68 are typically formed by perforation, scoring, or similar methods known to those skilled in the art. First and second lines of weakness 66, 68 thereby form removable header 70 encompassing zipper 30 thereby providing tamper evidence as the removable header 70 must be removed by tearing along first and second lines of weakness 66, 68 prior to opening zipper 30.

Second side seal 22 is formed slightly inwardly adjacent from the rightmost edge of front and rear panels 16, 18 thereby providing free side ends of front and rear panels 16, 18 wherein optional hang aperture 72 is formed, allowing package 10 to be hung in an orientation ninety degrees counter-clockwise from the orientation shown in FIG. 1.

Additionally, first and second flanges 36, 38 are sealed to each other along first vertical face 74 facing first notch 50 thereby forming first internal vertical seal 76 and first endstop 77. Likewise, first and second flanges 36, 38 are sealed to each other along second vertical face 78 facing second notch 52 thereby forming second internal vertical seal 80 and second endstop 81. First and second endstops 81 are typically formed ultrasonically and prevent slider 44 from sliding from the ends of zipper 30.

As shown in FIG. 6, the method to manufacture the package or bag uses a driven band, band sealer to decrease the drag induced to film 12 by zipper 30. An encoder is used to send a signal to the stepper motors to match the film speed. Band sealers are used to seal the zipper onto a continuously moving web. The band prevents the film from sticking to the seal bars.

Thus the several aforementioned objects and advantages are most effectively attained. Although preferred embodiments of the invention have been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims.

Claims

1. A reclosable package or bag, comprising:

a bottom wall, a first side wall and a second side wall;

a first side seal formed by sealing first side edges of the bottom wall, the first side wall and the second side wall to each other, and a second side seal formed by sealing side second edges of the bottom wall, the first side wall and the second side wall to each other;

a zipper, sealed to the first side wall and the second side wall, including a first profile and a second profile, the first profile including a first interlocking element and a first flange, the second profile including a second interlocking element and a second flange;

wherein first and second ends of the zipper include respective first and second notches wherein respective first and second portions of the interlocking elements are removed, wherein first and second portions of the flanges remain below the respective first and second notches; and

wherein the first portion of the flanges is sealed in the first side seal and the second portion of the flanges is sealed in the second side seal.

2. The reclosable package or bag of claim 1 wherein the first and second side seals are free of the first and second interlocking elements.

3. The reclosable package or bag of claim 1 wherein the first and second side walls extend from the bottom wall.

4. The reclosable package or bag of claim 3 wherein the bottom wall and first and second side walls are formed from a single sheet of web and wherein folds are formed between the first side wall and the bottom wall and between the second side wall and the bottom wall.

5. The reclosable package or bag of claim 4 wherein the single sheet of web is formed from polymeric material.

6. The reclosable package or bag of claim 4 wherein the zipper includes a slider.

7. The reclosable package or bag of claim 5 wherein the first flange is sealed to an interior of the first side wall and the second flange is sealed to an interior of the second side wall.

8. The reclosable package or bag of claim 7 wherein the upper edge of the first side wall and the upper edge of the second side wall are sealed together in an upper seal thereby forming a header encompassing the zipper, and wherein the header includes at least one line of weakness for removing the header.

9. The reclosable package or bag of claim 8 wherein the upper seal is a fin seal.

10. The reclosable package or bag of claim 8 wherein the first flange is sealed to the second flange along a first internal seal line along an edge of the first notch inwardly adjacent from the first side seal and along a second internal seal line along an edge of the second notch inwardly adjacent from the second side seal.

11. The reclosable package or bag of claim 10 wherein the first and second internal seal lines terminate in respective first and second endstops which limit travel of the slider.

12. A reclosable package or bag, comprising:

a wall structure;

a first side seal and a second side seal formed in the wall structure;

a zipper including a first profile and a second profile, the first profile including a first interlocking element and a first flange, the second profile including a second interlocking element and a second flange;

wherein first and second ends of the zipper include respective first and second notches wherein respective first and second portions of the interlocking elements are removed, wherein first and second portions of the flanges remain below the respective first and second notches; and

wherein the first portion of the flanges is sealed in the first side seal and the second portion of the flanges is sealed in the second side seal.

13. The reclosable package or bag of claim 12 wherein the first and second side seals are free of the first and second interlocking elements.

14. The reclosable package or bag of claim 12 wherein the wall structure is formed from a single sheet of web forming a bottom wall, a first side wall and a second side wall.

15. The reclosable package or bag of claim 14 wherein the single sheet of web is formed from polymeric material.

16. The reclosable package or bag of claim 14 wherein the zipper includes a slider.

17. The reclosable package or bag of claim 15 wherein the first and second flanges are sealed to an interior of the wall structure.

18. The reclosable package or bag of claim 17 wherein the wall structure includes a header encompassing the zipper, and wherein the header includes at least one line of weakness for removing the header.

19. The reclosable package or bag of claim 18 wherein the first flange is sealed to the second flange along a first internal seal line along an edge of the first notch inwardly adjacent from the first side seal and along a second internal seal line along an edge of the second notch inwardly adjacent from the second side seal.

20. The reclosable package or bag of claim 19 wherein the first and second internal seal lines terminate in respective first and second endstops which limit travel of the slider.