Device and system for modified atmosphere packaging
A focal point gassing device or system including a gas supply tube operably connected to supply gas to a focal point gassing head and a screen attached to the lance head, wherein the screen provides high velocity laminarized and directed flow gas to product moving through a vertical form/fill/seal packaging system. The vertical packaging system includes a focal point gassing device and a gassing lance to provide gas to product as it moves from a packaging hopper through a filling tube and into the package. The packaging system includes a gassing control system monitor and adjust the flow of gas to the gassing apparatus.
The present application claims priority to U.S. Provisional Application No. 60/658,750 filed Mar. 3, 2005, titled “Device and System for Modified Atmosphere Packaging”, the entirety of which is incorporated by reference.
FIELD OF THE INVENTIONThe invention relates to apparatus for exposing product to a controlled and/or modified atmosphere environment, and more particularly to a gassing apparatus for delivering gasses and mixtures into packages.
BACKGROUND OF THE INVENTIONVarious products, including food products and any other products having an adverse reaction to air, are packaged in a modified atmosphere and/or a controlled environment. Various attempts have been made to efficiently package these products in modified atmosphere and/or controlled environments using vacuum and/or controlled environments.
Various food products, including nuts, snacks, cheese, meats, fruits, and vegetables, are packaged under regular atmospheric conditions. Many of these products are presented in supermarkets, for example, in bags, cartons, or cardboard containers with a plastic or cellophane wrap covering the product. One problem with this type of packaging is that the goods have a limited shelf life, which for many products is only several days to a week.
Removing air during packaging is a problem in weighing and filling machines, which automate the packaging process. The space available for gassing operations is often limited in machines such as combination weighers, which employ weighing buckets and timing hoppers to meter the product and fill packages making it difficult to remove unwanted air. In packaging assemblies that use hoppers or collating funnels to direct the material to be packaged, the material continues to pull in unwanted air as it moves down the hopper or funnel. Furthermore, the speed at which packages are filled limits the ability to reduce the amount of air in the product to the desired level prior to sealing.
It would be desirable to have a gassing system and apparatus that overcomes the above disadvantages and limitations.
SUMMARY OF THE INVENTIONThe present invention provides a gassing device for positioning within a food hopper or scale collating funnel. The gassing device comprises an elongated gassing tube including a gas inlet at a first end, a gas dispensing device including a top portion and a bottom portion, the bottom portion including a sidewall tapering inward toward a bottom end of the bottom portion, the tapered sidewall and the bottom end including a gassing screen.
Another aspect of the invention provides a system for controlling atmosphere in a food filled package. The system includes a hopper, a forming tube operably attached to the hopper, a first gassing device including a gassing tube positioned coaxial with the forming tube and within the hopper, and a gas screen in communication with a bottom end of the gassing tube to dispense gas adjacent a focal point defined by a hopper wall profile. The system further includes at least one second gassing device including a gas inlet and gas rail positioned adjacent a bottom end of the forming tube and directing controlled environment gas downward into a package positioned beneath the forming tube.
Yet another aspect of the invention provides a method for controlling atmosphere in a food filled package. The method for controlling atmosphere in a food filled package comprises flowing controlled environment gas from a first region above and adjacent a focal point of a food hopper toward food traveling downward along a perimeter of the hopper toward a forming tube.
The foregoing and other features and advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiment, read in conjunction with the accompanying drawings. The drawings are not to scale. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims and equivalents thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The hopper assembly 30 includes a hopper 32 for receiving product from at least one of the plurality of weighing buckets 20 and bracket 34 (
Product flows from hopper 32 into and through filling tube 40 to be packaged by packaging assembly 50. Product is gassed as it passes through the hopper 32 and filling tube 40 by the gassing assembly. Packaging system 10 includes at least one apparatus for gassing the product prior to packaging the product in a sealed package. Gas is introduced into and along the packaging process to reduce the presence of air included with the packaged product. As used herein, gas includes any gas or mixture used to provide a modified or controlled environment around a product, such as inert gas, carbon dioxide, oxygen, nitrogen, and combinations of gases.
The focal point gassing device 60 is operably attached to and suspended from a bracket 25 positioned substantially above hopper 32. The focal point gassing device 60 is operably attached to the bracket 25 via an attachment clip 68. In one embodiment, bracket 25 is adjustable in a vertical direction in order to change the location of the focal point gassing device 60. The attachment clip 68 can be any suitable material and configuration required to maintain the focal point gassing device 60 in position on bracket 25. Focal point gassing device 60 is positioned co-axial with the filling tube 40. In one embodiment, focal point gassing device 60 is operably attached to the bracket 25 via a pair of set collars.
A gas supply (not shown) attached to the gas connector 62 provides gas through the supply tube 64 to the focal point gassing head 66. The supply tube 64 and gas connector 62 can be any suitable hardware for connecting the focal point gassing head 66 to a gas supply system and for locating the focal point gassing head 66 in the desired position to dispense the gas. In one embodiment, the gas supply tube 64 is a rigid pipe, such as a stainless steel pipe. The supply tube 64 can be made of any material compatible with the gas and the product. Exemplary materials for the supply tube 64 include, but are not limited to, plastic, non-ferrous metal or stainless steel. One exemplary application as illustrated in
The focal point gassing head 66 is located near the focal point of the hopper 32 or scale hopper 40, where the gas is needed. The focal point 38 of the hopper is defined by the inside wall 34 of the hopper 32 and is the central point where, if the wall of the hopper were extended to form a cone (illustrated by dashed line 36), the wall would converge to a single point.
In one embodiment, focal point gassing head 66 comprises top portion 90 and bottom portion 92. Top portion 90 is operably connected to gas supply tube 64. Top portion 90 may be connected to gas supply tube 64 by any means known in the art such as by welding or by a threaded connection. Alternatively, top portion 90 may be formed integrally with gas supply tube 64.
Top portion 90 may be composed of stainless steel. Top portion 90 is operably connected to bottom portion 92 and interface 94. In one embodiment, top portion 90 is connected to bottom portion 92 by welding. In another embodiment, top portion 90 is connected to bottom portion 92 by a threaded engagement. Those with skill in the art will recognize that the shape of top portion 90 may vary depending on the application. Other embodiments of focal point gassing device 60 may eliminate top portion 90. In other embodiments, top portion 90 is a plate having an opening for receiving supply tube 64, the periphery of the plate being operably connected to bottom portion 92. In one embodiment, a seal 63 is disposed between top portion 90 and bottom portion 92 to prevent or reduce gas leakage.
Bottom portion 92 comprises a support 96 and a cone-shaped screen 98 attached to support 96. Bottom portion 92 receives gas from supply tube 64 and delivers a targeted (focused) gas flow (arrow 102) and a laminarized gas flow (indicated by arrows 104, 105) through screen 98, described in more detail below. The laminarized gas flow 104, 105 typically has a low velocity allowing it to form a blanket flow along the hopper wall to bathe the product in gas as it moves down the hopper towards the filling tube. Targeted gas flow 102 provides a high velocity flow directed towards the focal point 38 of the hopper. Bottom portion 92 may have an elongated cone-shaped screen as shown in
The screen 98 can be made of any material compatible with the gas and the product. Typical materials for the screen 98 include plastic, non-ferrous metal or stainless steel. The screen 98 is porous and offers a flow resistance to convert the gas flow 106 exiting supply tube 64 to either targeted gas flow 102 or to the laminarized gas flow 104, 105. In one embodiment, the screen 98 has a mesh size of between about 10-100 microns. In another embodiment, a mesh size of 75 microns is used. Screen 98 may be composed of a plurality of plies to provide for varying degrees of flow resistance. In one embodiment, the screen 98 includes a five-ply wire screen portion indicated by flow arrows 104 and a nine-ply wire screen portion indicated by flow arrows 105. Those skilled in the art will appreciate that different numbers of plies and mesh sizes can be used for different applications. In one embodiment, the screen 98 has between 2 and 10 plies. In one embodiment, screen 98 comprises an area at tip 67 for providing the targeted gas flow 102. In this embodiment, screen 98 may have a single ply of screen. Those with skill in the art will recognize that the screen 98 at point 67 may have various other arrangements of ply and mesh size suitable for supplying a targeted high velocity gas flow directed towards the focal point 38. The screen 98 can be attached to the support 96 by welding, braising, or soldering. In another embodiment, screen 98 is composed of a porous polymer material, such as, for example, polyethylene and polypropylene. In this embodiment, screen may include layers of polymer having varying degrees of porosity. The focal point gassing head 66 and/or screen 98 can be ground, shaped, and polished to a final shape and surface finish as desired.
In another embodiment of a focal point gassing device 60 made in accordance with the present invention, the focal point gassing device 60 is composed of a material that may be placed proximate a metal detector without interfering with the operation of the metal detector when screening the material to be packaged for metal. In one such embodiment, the entire device is composed of plastic. In another embodiment, the focal point gas head is plastic. Those with skill in the art will recognize that there are myriad other materials suitable for manufacturing a focal point gassing device 60 that will not interfere with the operation of a metal detection device.
Gassing lance 74 and gas supply tube 76 are composed of material compatible with the gas and the product. Gassing lance 74 includes screen 75. Screen 75 can be made of any material compatible with the gas and the product. Typical materials for the screen 75 include plastic, non-ferrous metal or stainless steel. The screen 75 is porous and offers a flow resistance to convert the gas flow exiting supply tube 76 to laminarized gas flow. In one embodiment, the screen 75 has a mesh size of between about 10-100 microns. In another embodiment, a mesh size of 75 microns is used. Screen 75 may be composed of a plurality of plies to provide for varying degrees of flow resistance. Those skilled in the art will appreciate that different numbers of plies and mesh sizes can be used for different applications. In one embodiment, the screen 75 has between 2 and 10 plies. The screen 75 can be attached to the gassing lance 74 by welding, braising, or soldering.
Focal point gassing device 660 comprises a gas supply tube 664 and a focal point gassing head 666 in fluid communication with gas supply tube 664. In one embodiment, gas supply tube 664 is threadedly attached to focal point gassing head 666 via a threaded attachment 678. Focal point gassing head 666 includes two gas receiving chambers 670 and 672 for receiving gas from gas supply tube 664. Gas receiving chambers 670 and 672 are defined by a sidewall 668 of the gassing head. Focal point gassing head 666 includes a gassing screen 672. In one embodiment, gassing screen 672 comprises a plurality of openings 680 for dispersing gas from the gassing chamber toward the product moving through the hopper and into the filling tube. The plurality of openings are defined by the sidewall 668 of the focal point gassing head. In operation, gas received into chambers 670 and 672 exits the focal point gassing head through a plurality of openings 680. Openings 680 are configured to direct the gas toward the product as the product descends the hopper and into the filling tube. The pattern and number of openings 680 may vary depending-on the application. In other embodiments, the size of the openings 680 may vary depending on the application and the product that is being packaged. In one embodiment, a focal point gassing device 660 comprising a polymeric material is particularly well suited for use in a packaging system that incorporates a metal detector for detecting metal in the product as the product is packaged.
Returning to
During operation, the focal point gassing head 66 of the focal point gassing device 60 is disposed to supply gas to a region adjacent to the focal point 38 of the hopper 32 and gas lance 74 is disposed to supply gas to a region adjacent the lower end 72 of filling tube 40. Preferably, focal point head 66 is positioned so as not to interfere with the flow of product through the hopper 32 and to the filling tube 40. In one embodiment, hopper 32 is designed to allow the product to be single filed along the hopper wall so as not to bunch-up at the entrance to the filling tube 40.
During the packaging process, as the product moves down the walls 34 of the hopper 32 toward filling tube 40, the product passes near the focal point gassing head 66. Laminarized gas 104, 105 exiting the bottom portion of focal point head 66 drives a substantial portion of the oxygen surrounding the product as it leaves the weighing buckets away from the product. The focused gas flow 102 exiting focal point head 66 at point 67 drives the gas toward the product as the product passes the focal point thereby removing and stripping more of the oxygen surrounding the product.
At the same time, gas flowing from gassing lance 74 bathes the lower end 44 of filling tube 40 and the formed package with gas in order to drive away more residualmore residual oxygen. Gas from gassing lance 74 also rises within filling tube 70 to encounter the product as the product moves down the filling tube and into the package.
In one embodiment, the flow of gas from the focal point head 66 and the gas lance 74 is monitored and controlled by gassing controller 80. In one embodiment, gassing controller 80 can control the flow of gas in response to the amount of oxygen detected in the product or by the oxygen level sensed by oxygen sensor 84. In another or the same embodiment, gassing controller 80 controls the flow of gas based on whether product is present within the packaging system 10. In one embodiment, the flow rate of gas comprises a higher flow rate when product is dropping through the packaging system into a waiting package and a lower flow rate between drops of product i.e., when the buckets are filling with product prior to dropping the product into the hopper. In another embodiment, the gas flow rate is substantially zero between drops of product through the packaging system. Pulsing the flow of gas through the system depending on whether product is traveling through the system can increase the efficiency of gas usage and may decrease or eliminate the wasting of the gas for certain products and configurations.
In another embodiment, the controller 80 dynamically adjusts the percent of gas flow between the gas lance 74 and focal point gassing head 66. In an example, the total gas flow may be split between the focal point gassing head 66 and gas lance 74 in a 50:50 ratio to achieve the desired reduction in residual oxygen present in the package. This 50:50 ratio may be adjusted to an 80:20 when the product is moving through the hopper and into the filling tube 40 such that 80 percent of the total gas flow exits the focal point gassing lance head 66 and 20 percent exits the gassing lance 74. Then, as the product moves through the filling tube 40 and into the package the ratio may change to a 20:80 split so that 80 percent of the gas flow exits the gas lance 74. Those with skill in the art will appreciate that the ratio of gas flowing from the various gassing apparatuses may change depending on the application.
In another example, the total flow of gas from the focal point gassing head 66 and gas lance 74 may be adjusted based on a determination of the percent residual oxygen measured by oxygen analyzer 86 operably connected to gassing controller 80. In this example, if the percent oxygen is above a predetermined level as measured by the oxygen analyzer, gassing controller 80 may increase the flow of gas to either, or both of, the focal point gassing head 66 or gas lance 74.
At step 910, food is released into a hopper of the packaging system. At step 920, controlled environment gas flows from a first region adjacent a focal point of a food hopper toward food traveling downward along a perimeter of the hopper toward a forming tube. In one embodiment, flowing controlled environment gas from a first region adjacent the focal point comprises positioning a tip of the focal point gassing device at the focal point of the food hopper. In another embodiment, flowing controlled environment gas from a first region adjacent a focal point comprises positioning a tip of the focal point gassing device above the focal point of the food hopper. In another embodiment, flowing controlled environment gas from a first region adjacent the focal point comprises positioning a tip of the focal point gassing device below the focal point of the food hopper.
At step 930, controlled environment gas is released to flow downward from a second region adjacent an outlet of the forming tube into a package positioned at an end of the forming tube.
At step 940, the package environment is determined. In one embodiment, the gassing controller measures the amount of oxygen present in the package as the package is being filled. In another embodiment, the gassing controller measures the amount of oxygen in an area adjacent the opening of the package. In another embodiment, the gassing controller measures the amount of oxygen in the product as it travels down the filling tube.
At step 950, flow through from the first region and the second region is controlled by the controller based on the determined package environment. In one embodiment, the gassing controller adjusts the flow of gas based on the level of oxygen determined in the package or in the product traveling to the package. In another embodiment, the controller dynamically adjusts the percent of gas flow between the gas lance 74 and focal point gassing head 66. In an example, the total gas flow may be split between the focal point gassing head 66 and gas lance 74 in a 50:50 ratio to achieve the desired reduction in residual oxygen present in the package. Method 900 ends at 960.
In another embodiment, method 900 includes reducing the flow of gas from the first region and the second region based on the determination of the presence or absence of product moving through the hopper and/or the filling tube. In one embodiment, the flow of gas is reduced during a filling run between drops of product into the hopper. In another embodiment, the gas flow is turned off between drops of product into the hopper and turned on when product is detected in the hopper. In one embodiment, the presence of product in the hopper is detected by a motion sensor located adjacent a top portion of the hopper. In this embodiment, a signal from the motion sensor is sent to the gassing controller to activate the flow of gas from the gassing apparatus.
While the embodiments of the invention disclosed herein are presently considered to be preferred, various changes and modifications can be made without departing from the scope of the invention. The scope of the invention is indicated in the appended claims, and all changes that come within the meaning and range of equivalents are intended to be embraced therein.
Claims
1. A gassing device for positioning within a food hopper or funnel, comprising:
- an elongated gassing tube including a gas inlet at a first end;
- a gas dispensing device including a top portion and a bottom portion, the bottom portion including a sidewall tapering inward toward a bottom end of the bottom portion, the tapered sidewall and the bottom end including a gassing screen.
2. The device of claim 1 wherein the gassing screen comprises a plurality of plies of porous mesh.
3. The device of claim 1 wherein the gassing screen comprises a laminarized flow screen and a focused flow screen.
4. The device of claim 3 wherein the laminarized flow screen comprises a first portion having a first plurality of mesh plies and a second portion having a second plurality of mesh plies.
5. The device of claim 1 wherein the gassing screen comprises a plurality of openings defined in the sidewall.
6. A method for controlling atmosphere in a food filled package, the method comprising:
- flowing controlled environment gas from a first region adjacent a focal point of a food hopper toward food traveling downward along a perimeter of the food hopper toward a forming tube.
7. The method of claim 6 further comprising:
- flowing controlled environment gas downward from a second region adjacent an outlet of the forming tube into a package positioned at an end of the forming tube.
8. The method of claim 6 further comprising:
- determining a package environment;
- controlling flow through from the first region and the second region based on the package environment.
9. The method of claim 6 wherein flowing controlled environment gas from a first region adjacent the focal point comprises positioning a tip of the focal point gassing device at the focal point.
10. The method of claim 6 wherein flowing controlled environment gas from a first region adjacent a focal point comprises positioning a tip of the focal point gassing device above the focal point.
11. The method of claim 6 wherein flowing controlled environment gas from a first region adjacent the focal point comprises positioning a tip of the focal point gassing device below the focal point.
12. A system for controlling atmosphere in a food filled package, comprising:
- a hopper;
- a forming tube operably attached to the hopper;
- a first gassing device including a gassing tube positioned coaxial with the forming tube and within the hopper, and a gas screen in communication with a bottom end of the gassing tube to dispense gas adjacent a focal point defined by a hopper wall profile; and
- at least one second gassing device including a gas inlet and gas rail positioned adjacent a bottom end of the forming tube and directing controlled environment gas downward into a package positioned beneath the forming tube.
Type: Application
Filed: Mar 3, 2006
Publication Date: Sep 28, 2006
Inventors: James Sanfilippo (Barrington Hills, IL), John Sanfilippo (Barrington Hills, IL), Javier Soria (Northlake, IL)
Application Number: 11/368,236
International Classification: B65B 31/04 (20060101);