The present invention relates generally to the art of bag making.
There are many type of bags and equipment to make them. Bags are designed with various manufacturing concerns in mind, including ease of manufacturing, handles, type of material, type of closure, as well as features related to the bag when filled with product such as ability to stand on its own, the ability to stack easily, the ability to display the product name when stacked, etc. Often designing a bag to enhance one or more features results in a trade off of other features.
For example, relatively easy to manufacture bags with a zipper are made by sealing one machine direction edge of a bag to form the bottom, and affixing a zipper on the other machine direction edge. However, while easy to manufacture, the bag cannot stand on its own. Affixing, as used herein, includes attaching so that it is not easily removed, such as sealing, melting, together, gluing, etc. Machine direction edge, as used herein, includes an edge that is parallel to the machine direction. Machine direction, as used herein, includes the direction a film travels through a machine.
Different uses for bags make certain features more or less important. For example, bags used for pet food would preferably have a two-dimensional bottom so that the bag can stand on its own when filled. Another desirable feature for pet food bags is that they form a cuboid when filled, to make shipping and stacking in stores easier. (Cuboid, as used herein, includes a six sided shape with generally right angles between the sides.) Moreover, they would preferably present a side of the bag (as opposed to the top or bottom) when stacked so customers can easily read the label. Handles (one or more straps, loops, etc that may be used to pick up a bag) make a bag that is heavy when filled easier to carry. Also, a bag formed of multiple walls helps avoid dimpling of the outer walls of the bag by the pet food and help prevent grease saturation to the outer surface (thus preserving the appearance of the bag). Customers might also prefer a pet food bag with a resealable closure (a closure that may be resealed by the consumer, such as a zipper, hook and loop, friction fit, etc.), and/or has a tamper-evident feature (a feature that can be visually inspected to determine if it has been opened previously). Of course, ease of manufacture is desirable to reduce costs.
Most bags produced thus far cannot provide all or even most of these features. For example, typical pet food bags have non-resealable tops. Also, they cannot stand on their own, and their shape is not conducive to stacking. If they are stacked, it is usually on their side, and the stack is often unstable, with only a thin profile of the top of each bag visible to the customer.
One prior art bag that did provide some of these features is shown in U.S. Pat. No. D444,948, to Buchanan et al. That bag has a rectangular bottom and a cuboid shape (when filled). Even when filled the top can lay flat on the top of the cuboid, for ease of stacking. The side of the bag is presented to the customer when stacked. A handle is attached, and a hook and loop top seal allows for resealing. While this bag has advantages over the prior art it would be costly to manufacture, and the top resealable closure does not extend across the entire top—thus the entire top isn't resealable.
Accordingly, a bag that enjoys one or more of the features mentioned above, yet is not expensive or difficult to manufacture, is desirable.
According to a first aspect of the invention a bag comprises a lower portion and an upper portion. The lower portion has a generally rectangular bottom with first, second, third and fourth bottom edges. It also has a generally rectangular front, back left and right walls, each having a lower edge joined with the a bottom edge. The upper portion is joined to the lower portion, and has a zipper closure at a top thereof.
According to a second aspect of the invention a bag includes the upper portion is joined to the lower portion, and has a top peak with a resealable closure that extends the length thereof.
According to a third aspect of the invention a bag includes a lower portion and an upper portion joined to the lower portion. The lower portion has a generally rectangular bottom with first and second pairs of generally parallel sides. Pairs generally vertical walls are attached at lower edges thereof to the pairs of generally parallel sides. Four generally vertical corner seals, each joining one of the first pair of generally vertical walls to one of the second pair of generally vertical walls, extend part of the way up the generally vertical walls.
According to a fourth aspect of the invention a plurality of bags are formed from seven individual webs moving in a machine direction. Each bag is formed with transverse seals extending the width of the webs. Each bag has a resealable closure mounted on a first machine direction edge of the bag, and a folded web gusset and a bottom seal on the second machine direction edge of the bag. A plurality of corner seals are disposed between the transverse seals, and extend a portion of the way from the from the bottom seal toward the resealable closure.
According to a fifth aspect of the invention a machine for making bags from four different films includes an input section, and a sealing section. Each section has at least one driven roller that contacts the film as it follows a film path and moves in a machine direction. The sealing section is downstream of the input section, and has two transverse sealers, spaced in the machine direction, such that each bag is formed with spaced transverse seals extending the width of the webs. It also has a resealable closure fixture, mounted on a first machine direction edge of the bag, and a gusseted insert fixture, on a second machine direction edge of the bag, and a plurality of corner sealers, disposed between the transverse sealers, and extending a portion of the way from the from the gusseted insert fixture toward the resealable closure fixture.
According to a sixth aspect of the invention a method of making a bag includes forming a lower portion with a bottom and forming an upper portion, joined to the lower portion, and having a top, and affixing a zipper closure to the top.
According to an eighth aspect of the invention a method of making a bag includes forming a lower portion having a bottom and two pair of generally parallel sides walls, each side wall being adjacent to two of the other side walls and each attached on lower edges thereof to the bottom. Also, four generally vertical corner seals are formed, and each joins one of the first pair of generally vertical walls to one of the second pair of generally vertical walls. The corner seals do dot extend the entire height of the generally vertical walls. An upper portion is formed and joined to the lower portion.
According to a ninth aspect of the invention a method of forming a plurality of bags from seven individual webs moving in a machine direction, comprises forming spaced transverse seals extending the width of the webs, affixing a resealable closure mounted on a first machine direction edge of the bag, affixing a gusseted insert to a second machine direction edge of the bag, and forming corner seals between the transverse seals, that extend only a portion of the way from the from the bottom seal toward the resealable closure.
According to a tenth aspect of the invention a method of making a bag includes forming a lower portion to have a bottom with four side walls attached on lower edges thereof to the bottom, and forming an upper portion, joined to the lower portion, and having a top peak with a resealable closure affixed along the entire length of the top peak.
The upper portion includes a top peak with a zipper closure and/or a tamper-evident feature that extends the length thereof, in various embodiments.
Four generally vertical corner seals join the front wall and the left side wall, and the corner seals do not extend the entire height of the walls, in another embodiment.
The side walls each have a generally vertical side seal extending from the top of the bag towards the bottom, below an upper end of the corner seals or to the bottom in various embodiments.
The bag is one of a plurality of bags formed from a film, and the side seals separate adjacent bags in another embodiment.
The bottom is a folded web forming a gusset and sealed to the front and back walls in another embodiment.
The lower portion is comprised of a laminated material, and/or the upper portion is comprised of a poly material, in various embodiments
A handle is sealed between layers of the laminate and poly material, near the top of the lower portion in another embodiment.
The bag, when filled with product to a fill level, the shape of the filled portion is generally a cuboid, and/or the upper portion lays flat to form a top of the cuboid, in various embodiments.
The peak is formed at least partially from a top edge on each of the front and back walls, in another embodiment.
One pair of generally vertical walls are formed from seven individual webs of material which includes a folded web to form the bottom, in another embodiment.
Angle seals extend from each transverse seal to the bottom seal, and each angle seal meets the transverse seals and the bottom seals at a distance from a point where the transverse seals meet the bottom seal, in another embodiment.
Other principal features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description and the appended claims.
Before explaining at least one embodiment of the invention in detail it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. Like reference numerals are used to indicate like components.
While the present invention will be illustrated with reference to it should be understood at the outset that the invention is described with respect to a preferred bag with preferred seals and manufactured in a preferred manner, the invention can also be implemented with other bags, having other shapes, made with other seals, and manufactured in other ways.
Generally, the preferred embodiment is a bag made to stand on its own when filled, and to a bag with seals disposed in a desirable fashion such that the bag is inexpensive to manufacture, and can have a full length resealable closure. More specifically, the bag has a lower portion that when filled with product has a generally cuboid shape, and an upper portion that lays flat on the top of the cuboid. Generally a cuboid, as used herein, includes shapes that are similar to cuboids, but do not need to have generally 90 degree angles between sides, for example the sides may angle outward.
The bottom is generally rectangular, and the lower portion has four generally vertical walls with lower edges attached to bottom edges (i.e., the edges of the rectangular bottom). Alternatives provide for non-vertical walls and non-rectangular bottoms. The walls extend upward at generally 90 degree right angles, and the front and back are generally parallel, as are the side when filled. Generally rectangular, as used herein, includes a four sided shape that has generally 90 degree angles. Generally 90 degree angles, as used herein, includes angles that appear close to 90 degrees, and serve the purpose of a 90 degree angle. Wall, as used herein, includes the sides of the bag. Vertical, as used herein, includes generally perpendicular to the bottom of the bag.
Four corner seals join the front and back walls to side walls. The four corner seals extend to the top of the lower portion, or to the fill level, in the preferred embodiments. The seals can extend higher or lower in alternative embodiments. The corner seals and rectangular bottom help the bag stand on its own when filled, and to have a cuboid shape.
Each side wall has a side seal (i.e., a seal on a side, preferably midway front to back), disposed generally vertically, and midway front to back. The side seal extends from the top of the bag towards the bottom, preferable to the lower portion, and more preferably to the bottom. Thus, the only seals extending to the top are the side seals, and the top of the bag is a peak formed from the top edges of the front, back and side walls, and extending from side seal to side seal. The upper portion of the bag does not have corner seals, and the peak is that which would be made if the mid-sides of a rectangle (at the top of the side seals) are pulled outward, drawing the front and back toward each other, until they meet and form a peak having a length equal to length of a side wall plus the length of the front or back wall. The lower part of the upper portion retains its rectangular shape, because it is attached to the lower portion, which has the four corner seals, and is filled with product. The upper edge of the lower portion may also include an insert to help retain the rectangular shape where the upper and lower portions meet.
Handles are sealed between the overlapping poly upper portion and the lower laminate layers, near the top of the lower portion, on the front and back walls. Sealing the handles to bag 100 in this manner gives good strength to the handle attachment area, and allows the user to easily carry the bag. A zipper closure, or other resealable closure, is preferably mounted to extend the entire length of the top peak.
Referring now to
Two bottom seals 207 are shown, as well as angle seals 211, which are on the side walls. They will be explained in greater detail below. Angle seals, as used herein, includes seals at an angle (other than 90 degrees) to the machine direction. Bottom seal, as used herein, includes the seals that will be at the bottom of a bag after it is filled.
Side seal 213 is shown, and extends from the top of bag 100 to the bottom in the preferred embodiment. It may be seen that the corner seals on the lower portion and the rectangular bottom helps form the cuboid bag shape, while the lack of corner seals on the upper portion allow the top of the bag to form a peak 214 with a zipper 215 extending the entire length thereof. A tamper proof or evident zipper feature seal 217 (such as that known in the prior art) is also shown. Other resealable closures may be used, including friction fit, hook and loop, etc. Handles are also shown.
Referring now to
Films 601 and 604 form the outer layer of the lower portion, and are preferably poly laminates that may have be printed with labels and/or decorative matter. Films 602 and 603 form the inner layer of the lower portion and are preferably made from a material (poly, olefin, nylon, etc.) that provides a desired property (impact resistance, strength, wear, etc.). The inner layer is a cross-filament laminate in the preferred embodiment. Poly films 611 and 612 overlap film 101-104 (at 108) and form the upper portion. A zipper 609 is applied, and a gusset insert 610 is also shown. The various films are sealed to form the desired bag,
The upper poly portion can be sealed to the lower laminate portion. The laminate will form the lower part 501 of bag 100, and the poly portion will form the upper portion 503 of the bag. Transverse seals 201 (generally perpendicular to the machine direction) are formed across the laminate portion only to form the corner seals. Transverse seals 213 are formed across the poly and laminate portions to form the side seals. Angle seals 211 are formed at an angle between side seals 213 and corner seals 201. The angle seals help to give the bag it's cube shape when filled.
The folded laminated 610 which forms the gusset web is sealed to the two laminate portions, on the machine direction edge to form the bottom of the bag. Gusseted insert, as used herein, includes a folded portion is sealed or affixed to one or more films, to form at least one gusset.
Side seals 213 also indicate the end of one bag and the start of the next. The seal can be cut in ½ using a guillotine style knife to help separate adjacent bags from one another, as is known in the art (separate includes physically disjoining or denoting the end of a leading bag and the start of a succeeding bag). Adjacent bags, as used herein, includes bags next to one another as they are formed from continuous film or films.
A zipper with a tamper-evident feature is affixed to the machine direction edge opposite the gusseted insert. The zipper is continuous because the peak extends the length of the side plus the front—thus there is no portion which cannot have the recloseable seal (which is different from the prior art). Other resealable closures are used in alternative embodiments.
Handles are sealed between the overlapping poly upper portion and the lower portion laminate near the top of the lower portion, which allows the user to easily carry heavy bags.
Referring now to
Web drive module 1 is an example of an input section. Input section, as used herein, includes a processing station that receives a film and feeds it to subsequent processing stations, it may include machinery for folding the film. Slider applicator module 8 is an example of a slider station with a resealable closure fixture. Resealable closure fixture, as used herein, includes a fixture that affixes a resealable closure to a film, and it may encompass distinct zipper and slider stations. Slider station, as used herein, includes a processing station applies a “slider” onto a pouch, usually in the machine direction. Cut off module 9 is an example of a cut-off station. Cut-off station, as used herein, includes a processing station that cuts the film, such as that used to separate adjacent pouches (such as at the side seals). Zipper sealer module 5 is an example of a zipper sealer station. Zipper sealer station, as used herein, includes a processing station that welds or forms a zipper onto a pouch, usually in the machine direction.
The lower portion material unwind 10, feeds the web in a continuous motion from roll stock through the Vee folder 11, which folds the web in approximately ½ and slits the web into two individual sheets prior to entering the web drive module 1.
The web drive module 1, has a driven rubber nip roller which feeds the webs in continuous motion into a dancer roll system which allows the webs to exit the web drive module for downstream processing in intermittent motion.
The corner sealer module 2, forms the corner seals that extend across the full width of only the lower portion material. It also allows for the registration compensation required to register the printing of the lower portion material to the printing of the inserted bottom gusset panel received from the inserted bottom gusset unwind 13, prior to sealing. The inner web material unwind 12, feeds the inner web material into the corner sealer module 2, which seals the lower portion material to the inner web material, thus forming the multi-wall bag construction feature.
The handle applicator module 3, feeds and seals a polyethylene carrying handle to the inner side of each individual side of the bag 100.
The extension module 4, includes an upper portion material unwind 14, which slits the upper portion material in approximately ½ and feeds the individual slit webs into the extension module 4, for downstream longitudinal sealing. A zipper material unwind 15, feeds the zipper track material into position for downstream zipper sealing.
The longitudinal & zipper sealer module 5, has a multiple of upper and lower heated longitudinal sealing bars positioned opposite each other to finish seal the inserted bottom gusset material to the lower portion material at it's lower machine direction edge, thus creating the bottom seal and forming the bag bottom. It also finish seals the two individual webs of upper portion material to the two individual upper machine direction edges of the lower portion material, thus captivating and finish sealing the handle material between the overlapping upper portion material and lower portion material. It also has upper and lower heated zipper sealing bars positioned opposite each other to finish seal the zipper track material to the inner surfaces of the upper machine direction edges of the upper portion material.
The cross seal module 6, has a multiple of upper and lower heated angle sealing bars 16, positioned opposite each other in a cross machine direction to form the angular seals required to produce a generally rectangular bag bottom. It also has a multiple of upper and lower heated cross sealing bars 17, positioned-opposite each other to finish seal and form the side seals of successive pouches in a cross machine direction. Servo drawroll 22, is positioned within cross seal module 6, to move the web through the process in registration and control web tensions in the cross sealing section.
The cross seal extension module 7, has a multiple of upper and lower water cooled bars 18, positioned opposite each other in a cross machine direction to cool the side seals prior to downstream individual pouch cut-off.
The slider applicator module 8, has a servo drawroll 21, to move the web through the process in registration and control web tensions through the cut-off section. The slide zipper closure mechanism and zipper track end termination clips are applied to the zipper track, thus creating the resealable bag 100 closure feature.
The cut-off module 9, has a servo drawroll 20, to move the web through the process in registration and feed the web to the servo cut-off knife which cuts the bag side seal in approximately ½, thus creating individual bags 100.
The stacking conveyor 19, accepts the individual cut bags 100, in a stack formation for easy operator packing and handling.
A gusseted insert fixture for sealing a gusseted insert is provided in the preferred embodiment, and is comprised of the sealing sections or modules. Gusseted insert fixture, as used herein, includes a fixture that applies a gusseted insert to one or more films. Sealing section, as used herein, includes one or more sections of a bag machine that includes one or more seal bars or other devices to form a seal on a film.
Cross sealer station or module, as used herein, includes a processing station that forms a cross-seal, such as the seals forming the bottom of the bag. Cross seal extension station, as used herein, includes a processing station that forms cross seals over an extended length. Angle sealers, as used herein, includes seal bars (or other seal-creating devices) disposed to create a seal angled (other than 90 degrees) relative to the machine direction. Corner sealers, as used herein, includes seal bars (or other seal-creating devices) disposed to create a seal that will form a corner of the bag after it is filled. Transverse sealers, as used herein, includes seal bars (or other seal-creating devices) that apply a transverse seal.
A machine capable of having the appropriate sealing and other stations to implement the present invention is one such as that described in detail in U.S. Patent Application 20020155936, Wied et al. (and has as a co-inventor the inventor of the present invention), filed Apr. 23, 2001, and entitled Modular Pouch Machine, hereby incorporated by reference. Alternatives provide for the invention to implemented with other systems, that might or might not be modular.
Numerous modifications may be made to the present invention which still fall within the intended scope hereof. Thus, it should be apparent that there has been provided in accordance with the present invention a method and apparatus for a bag and machine to make it that fully satisfies the objectives and advantages set forth above. Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.
Number | Date | Country | |
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Parent | 10393491 | Mar 2003 | US |
Child | 11254449 | Oct 2005 | US |
Number | Date | Country | |
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Parent | 10314912 | Dec 2002 | US |
Child | 10393491 | Mar 2003 | US |