Vertical Flow Wrapper and Method To Produce Packages With A Reduced Gas Content

Abstract

A vertical flow-wrapper, which produces packages, with a frame/housing, at which a form-fill-tube, a longitudinal-sealing means and a cross-sealing means and a cutting means. A method to produce a package from a plane film.

Claims

1) A vertical flow-wrapper, which produces packages, comprising: a frame/housing, at which a form-fill-tube, a longitudinal-sealing means, a cross-sealing means and a cutting means are provided, and a compression means, which at least partially compresses each of the packages prior to and/or during providing a cross seal to each of the packages, the compression means is at least partially made from a flexible plastic or rubber material and is at least partially hollow.

2) (canceled)

3) (canceled)

4) The vertical flow wrapper according to claim 1, wherein the compression means is connected to a pressure source, which maintains and/or changes an internal pressure within a hollow section of the compression means.

5) The vertical flow-wrapper according to claim 1, wherein the compression means is provided parallel to the cross-sealing means.

6) The vertical flow-wrapper according to claim 1, wherein the compression means is provided as a longitudinal bar or as the segment of an arch.

7) The vertical flow-wrapper according to claim 1, wherein the a surface of the compression means comprises anti-sticking means and/or one or more bulge(s).

8) The vertical flow-wrapper according to claim 1, wherein the compression means is attached to the cross-sealing means.

9) A method to produce a package from a plane film, which is formed around a form-fill tube into a film tube, whose distal ends are connected by a longitudinal sealing means with a longitudinal seal, wherein a first cross seal is provided at the film tube by cross-sealing means and wherein the film tube is filled with a product before a second cross seal is provided at the film tube and the filled package are separated from the film tube by cutting means, wherein prior and/or during the provision of the second cross seal, a gas is pressed out of the package by compression means, wherein the compression means are at least partially hollow and the pressure in the compression means, can be controlled, or is maintained constant during the compression of the package.

10) The method according to claim 9, wherein the film tube is compressed in a vicinity of the second cross seal.

11) (canceled)

12) The method according to claim 9, wherein the compression means deform during the compression of the package.

13) (canceled)

Description

BRIEF DESCRIPTION OF THE FIGURES

[0028] FIG. 1 shows schematically the vertical flow-wrapper according to the invention.

[0029] FIGS. 2 and 3 depict the compression means 10.

[0030] FIGS. 4, 5, 5a show the connection of the compression means to the cross sealing means.

[0031] FIG. 5b shows a preferred embodiment of the shape of the compression means.

[0032] FIG. 6 shows a combination of a bellow and O-rings as compression means.

[0033] FIG. 7 show the package being compressed by the compression means.

[0034] In FIG. 1, the vertical flow-wrapper 1 according to the invention is schematically shown. A vertical flow wrapper is a packaging machine, which forms a plane film web into a film tube, which is transported along a form-fill tube 4. Two ends of this film tube are sealed together by a longitudinal sealing means 5. Subsequently, the packaging item is filled into the film tube and a cross-seal is applied to the film tube to close the package. Simultaneously or after applying the cross-seal, the finalized packages are cut off the film tube. The vertical flow wrapper comprises a frame/housing 8, at which a form shoulder 3, a form-fill tube 4 and longitudinal sealing means 5 and cross-sealing means 6 are provided. The vertical flow-wrapper may comprise gusset-forming means to form the bottom and/or the top of each package.

[0035] A web of a film 4, especially a weldable plastic film 4, is supplied from a reel 9, which supplies the plane film continuously or intermittently to a form shoulder 3, which shapes the film web into a rather tubular form around a form-fill tube 2. In the context of the present invention, a “tubular form” of the packages or of the film means any cross-sectional form including a circular form or another form, and especially a rectangular or generally a polygonal form. Longitudinal sealing means 5, which are provided downstream from the form shoulder, seal the edges to the film tube together. After sealing, the bottom of the package 7 can be formed by a special bottom forming means, for example gusset-forming means. Finally, cross seals, extending preferably perpendicularly to the direction of flow of the film, are applied, especially by means of cross-sealing means 6. These cross sealing means 6 apply to the package 7 not only an upper/second cross-seal closing the top of the package 7, but these cross-sealing means 6 advantageously also provide, preferably simultaneously a lower/first cross-seal defining the bottom of the subsequent, upstream package 7. The packages 7 produced are separated from one another by a cutting means, which are preferably incorporated into the cross-sealing means 6. Between the application of the bottom- and top-cross-seal of each package, the package is filled with the product, preferably an edible product. Prior and/or during the application of the upper cross seal, the package/film tube is compressed, so that a gas, e.g. air, in the package is removed.

[0036] FIGS. 2 and 3 show the compression means 10, which are in the present case provided as a bar, which is preferably provided horizontally and/or parallel to the cross sealing means. The compression means 10 is here depicted as a bellows. The compression means 10 can be connected to a frame 11, preferably by a reversible connection, which can be provided without tools. Two of these compression means co-act during the compression of the package/film tube. The compression means, particularly its jacket 15 is preferably made from a flexible material, such as silicon and/or rubber, particularly the part of the jacket that is contact with and/or faces towards the package/film tube. In the present case, the compression means has a constant cross section over its entire length, which can be square or rectangular, round or oval. FIG. 3 depicts a cut through the compression means according to FIG. 2. It can be seen, that the compression means can, at least partially, be hollow, so that it comprises a hollow section/pressure chamber 14. This hollow section, preferably with a constant cross section over its entire length, preferably comprises a connection 13 which connects the hollow section to a pressure source and/or through which the hollow section can be vented. The hollow section is preferably constant over the entire length of the compression means. The pressure source can be vacuum or excess pressure, so that the volume of the hollow section 14 can be in- and/or decreased. During operation the compression means is preferably compressed. During this compression, the pressure in the hollow section 14 is preferably maintained constant, at least after a certain pressure level has been achieved. The surface of the compression means 10, particularly the part of its jacket that comes in touch with the package/film tube can comprise anti-sticking means 16, like projections 16. The projections are preferably provided as rows, preferably equidistant rows. The projections in the rows are preferably equidistant.

[0037] FIGS. 4 and 5 depict the cross sealing/cutting means 6 and the compression means 10 connected to it. The cross sealing/cutting means 6 comprises two members, which are move towards each other to apply the cross seal and away from each other to open the passage, as depicted by the double arrows. One compression means 10 is connected to each member 6 via the frame 11, which comoved together with the members. Connection means 23, here pins 23, are used to connect the compression means 10 the frame 11. In the present case, the frame 11 comprises an array of holes which are preferably arranged equidistantly, so that the compression means 10 can be provided at different distances relative to the cross sealing means 6 and/or the compression means can be exchanged easily, preferably without tools. A scale 17 can be provided to assist attaching the compression means 10 to the frame.

[0038] FIG. 5a shows a preferred embodiment to fix the compression means 10 to the cross sealing/cutting means 6 and/or to the frame 11. In the present case fixation means 24, which are provided inside the compression means, here inside the hollow bellow and/or outside fixation means 25 are provided.

[0039] In general, a preferred means to fix the compression means 10 to the cross sealing/cutting means 6 and/or to the frame 11 is without tools, preferably utilizing one or more magnets. Preferably, means are provided which fix the compression means 10 to the cross sealing/cutting means 6 and/or to the frame 11 at the desired position.

[0040] FIG. 5b shows a preferred embodiment of the shape of the compression means 10. In the present case, the lower end, the end 26 that is directed towards the product is arch-shaped and can preferably follow the pile of a product filled into the bags. The arch may have the contour of the segment of a circle, the segment of an ellipse and/or of a polygon.

[0041] FIG. 6 shows a preferred embodiment of the compression means 10, here a combination of a bellows and one or more O-ring(s) 29. In the present case, two poles 27, are provided around which an O-ring is stretched. The O-ring can be held in position by grooves 28, which accommodate the O-ring 29. In the present case, seven O-rings can be provided in the seven parallel grooves 28.

[0042] FIG. 7 depict the package 7 and the compression means 10. The bag 7 comprises a longitudinal seal, not depicted, a lower, first cross seal 18 and a second, upper cross seal 19. “Upper” and “lower” relates to the direction of force of gravity. The cross seals 18, 19 are preferably provided perpendicular to the direction of motion of the film tube or package. The cross seals 18, 19 extend into and out of the paper plane. The package is filled with a packing item 21. Preferably, the cross seals extend horizontally during production. The compression means 10 preferably extend also horizontally and are preferably provided such that they compress the region between the second horizontal seal and the packing item, the upper end of the packing item. For the compression of the film-tube/package, the compression means 10 move towards each other as depicted by the arrow 22. The compression preferably takes place before the package 7 is hermetically sealed.

LIST OF REFERENCE SIGNS

[0043] 1 vertical flow-wrapper

[0044] 2 form-fill tube

[0045] 3 form shoulder

[0046] 4 film, film

[0047] 5 longitudinal-sealing means

[0048] 6 cross-sealing- and/or cutting means

[0049] 7 package, package, pouch

[0050] 8 frame/housing of the vertical flow-wrapper

[0051] 9 reel

[0052] 10 compression means, bellows

[0053] 11 frame for the compression means 10

[0054] 12 fastening means

[0055] 13 pressure connection means

[0056] 14 hollow section, pressure chamber

[0057] 15 jacket

[0058] 16 anti-sticking-means, projection

[0059] 17 scale

[0060] 18 first cross seal, lower cross seal

[0061] 19 second cross seal, top cross seal, upper cross seal

[0062] 20 transportation direction

[0063] 21 packaging item

[0064] 22 compression direction

[0065] 23 connection means, pin

[0066] 24 fixation means for the compression means, inside fixation means

[0067] 25 fixation means for the compression means, outside fixation means

[0068] 26 lower end of the compression means

[0069] 27 pole

[0070] 28 groove

[0071] 29 compression means, O-ring