Patent Description:
Vertical fill form and seal machines ("VFFS machines") are commonly used to bag particulate products, including, but not limited to, snack foods that are particulate in nature. Particulate snack foods include, but not limited to, potato chips, corn chips, and extruded snack pieces of various shapes and sizes. These usually enter near the top end of the VFFS machine in measured charges and are each then sealed into a package that is formed on the machine, from packaging film, to contain the snack food charge. The packaging film is most commonly of a heat sealable polymeric composition.

In some VFFS machines the package film advances downward around a forming tube where the free ends of the film are sealed together along the side of the forming tube and sealed transversely by a sealing device as it travels below the forming tube. The partially formed bag, having a sealed side and bottom end, is then filled with the particulate charge and the top of the bag being formed is sealed with another transverse seal. <CIT> discloses a vertical form fill and seal apparatus for packaging with a former and a film driver for moving a packaging film down around the former wherein an actuator is in mechanical communication with the film driver and wherein a controller is in communication with the actuator and the controller is configured to control a reciprocating force applied by the actuator.

In some VFFS machines, the motion of the packaging film is halted intermittently as the film is being transversely sealed to form the bag. The step of transverse heat sealing requires a finite amount of time to complete. Consequently, VFFS machines of this type are of intermittent operation. In other VFFS machines, which are of continuous operation, there is a jaw assembly that is adapted for continuous motion of the packaging film.

<FIG> depicts schematically a portion of an example of a conventional VFFS apparatus. In sequence, from the top, there is a weigher <NUM>, where particulates, for example particulate snack food to be packaged, are charged and weighed. The weigher <NUM> accumulates and discharges a specified charge of product corresponding to the amount of product which will occupy a single bag. Downstream from and below the weigher <NUM> is typically a funnel <NUM>, or a series of funnels, which receives and then directs the charge of product. Downstream from the funnel <NUM> is a product delivery cylinder <NUM>, which then receives the product charge. As used in a VFFS apparatus, the product delivery cylinder <NUM> is often referred to as a "former. " The packaging film <NUM>, dispensed from a roll <NUM>, is draped around the former <NUM> and travels downward. A side sealer <NUM> in slight touching relation to the film, seals the overlapping edges of the packaging film together to form a tube that continues to travel downward under urging from a film driver, such as belt driven rollers (one partially obscured) <NUM>, on opposed sides of the former <NUM> as the seal is formed. The sealing jaws <NUM> on either side of the packaging film <NUM> are each equipped on a leading face of the jaw with a heating element <NUM> that is moved inward to touch the film, and urge against the film, to form a transverse seal <NUM>, and then retract away from the film <NUM>. Once the transverse seal <NUM> is formed, the bottom of the tube of packaging film is closed. A charge of product is then delivered through the former <NUM> and into the sealed partially formed bag, which is in the form of a tube. Thereafter, as the film <NUM> continues to move downward, the sealing jaws again move so that the heating elements contact and urge against the top region of the partially formed bag to form another transverse seal <NUM>, and then retract away from the seal. Thus, there is formed a bag, sealed at top and bottom, with product therein. A blade may then cut the film above the top seal of the bag (and below the bottom seal of the next bag being formed in the process) to separate the bag from the film. Thus, the VFFS apparatus can fill, and make bags filled with particulates, either continuously without stopping film travel, or with intermittent stops of the film as each a bag is transversely sealed.

During the operations described above, the VFFS apparatus is stationary and does not move either up or down, or laterally. It is generally held in an immobile and fixed position by a support frame (not depicted).

According to the invention, there is provided a vertical fill, form and seal (VFFS) apparatus for particulates that promotes and facilitates the close-packing ("settling") of the particulates such that a smaller package is needed to contain a mass of particulates in a charge to the VFFS apparatus. The film former and film driver of the VFFS apparatus move up and down in a controlled manner to produce a gentle shaking action of particulates that are in a partially formed bag below the film former and that shake along with the film former, while the packaging film travels smoothly downward around the former. The gentle shaking is such as to minimize breakage in the case of fragile particulates, such as snack foods, and this can be readily ascertained by observation and appropriate adjustment by a person of skill in the art. Nonetheless, the gentle shaking is effective in causing the particulates to settle and to increase the bulk density of the particulates being bagged.

According to the invention, the VFFS apparatus for packaging a particulate charge has a film former configured for wrapping a packaging film around an outside surface thereof and for receiving a particulate charge therein. It also has a film driver that urges the film downward in a controlled manner. There is an actuator in mechanical communication with the former and film driver to apply a vertical reciprocating force to the both former as well as film driver to move them up and down in concert. Sealing jaws are located below the former to transversely seal packaging film exiting off the former to form a bag containing the particulate charge, when the apparatus is in use. A controller is in communication with the actuator and is configured to control a frequency and amplitude of the reciprocating force applied by the actuator. Accordingly, when in use, the synchronous reciprocal motion of the former and its associated film driver causes shaking of a partially formed bag of packaging film below the former. This shaking causes settling of particulates in the partially formed bag to thereby increase the bulk density of the particulates. As a consequence, a smaller package (less volume) can be used to contain the charge, as opposed to the package necessary when the same mass of charge was packaged in a VFFS that has a stationary film former and film driver.

As a direct consequence of the enablement of smaller packaging due to close packing of the particulate contents, smaller packages can be made, and packaging waste for disposal after use is reduced, thus minimizing landfill use. Further, the smaller packages enable use of smaller cartons. This translates to a greater number of cartons per truckload, since truck loads are very often limited by volume rather than mass, especially for low bulk density particulates, such as snack foods. Fewer truckloads result in savings in fuel consumption, and in reduction in carbon footprint. Accordingly, the technology provides energy savings as well as facilitating preservation and/or maintaining the environment.

In the exemplary embodiment, a minimum distance between the lower end of the former and the sealing jaws is maintained during the up and down movement of the former and the sealing jaws. This minimum distance permits tuckers to be inserted to shape the packaging film exiting off the base of the former for making a formatted bag, while the packaging film moves continuously through the apparatus without interruption.

Further, according to the invention, the sealing jaws move up and down in concert with the former.

Other features that are included in the exemplary VFFS apparatus include a side seal bar adjacent the former such that side seal bar moves up and down in concert with the former to maintain its vertical displacement relative to the former.

According to the invention, the package film driver, which is under control of the controller, and that moves the packaging film downward around the outside surface of the former, moves up and down in concert with the former. It thereby maintains a constant vertical displacement relative to the former and ensures smooth packaging film travel. The package film driver may operate to smoothly and continuously guide packaging film downward around the former, without interruption.

Further, in the exemplary embodiment which is not in the scope of the invention as defined by appended claims, the controller may be configured to intermittently stop applying reciprocal force and to stop the package film drive roller thereby stopping package film movement. This may take place at any useful point in the packaging cycle, for example, while a bag is being transversely sealed by the sealing jaws.

In the exemplary embodiment, the amplitude of the up and down motion is in the range from <NUM> to <NUM> and the frequency may be in the range <NUM> to <NUM>.

There is also provided a method of reducing an amount of packaging film necessary to package particulates in a vertical fill, form and seal (VFFS) apparatus according to claim <NUM>. The method includes moving a former and film driver of the VFFS apparatus up and down in a controlled synchronous reciprocation, while feeding a packaging film around the former. Further, forming a side seal in the packaging film while the former is in reciprocating up and down motion. And feeding a charge of an amount of a plurality of particulates to the apparatus and into the former to be packaged, while the former and film driver are in reciprocating up and down motion. Allowing the charge to exit from a base end of the former into a partially formed bag of the packaging film. The up and down motion of the former causes shaking of particulates in the partially formed bag such that the bulk density of the charge increases. In the event that the charge is of a fragile nature, the severity of the shaking may be appropriately adjusted by a person of skill in the art taking into account an acceptable level of breakage, depending upon the nature of the particulate product, and its market acceptance. Then, sealing the partially formed bag to form a bag containing the higher bulk density particulates. The reciprocating up and down motion of the former increases the bulk density of the particulates relative to the bulk density without the up and down motion, to permit bagging of the same mass of particulates in a smaller bag.

The exemplary embodiment of the method may further include maintaining a controlled distance between the former and the sealing jaws. And, the exemplary embodiment of the method may further include that the controlled distance allows insertion and removal of tuckers for making formatted bags, without interference with sealing jaw operation.

The method includes moving the sealing jaws up and down in concert with the former.

According to the invention the method further includes feeding the packaging film continuously, without intermittent stopping during packaging operations.

In the exemplary embodiment of the method, the amplitude of the up and down motion is in the range from <NUM> to <NUM>. And, the frequency of the up and down motion is in the range <NUM> to <NUM>.

In the exemplary embodiment of the method, the particulate charge may be snack food particulates. The snack food particulates may include, but is not limited to, potato chips, potato-based particulates, wheat based particulates, and com-based particulate snack foods.

The foregoing aspects and many of the attendant advantages of the present technology will become more readily appreciated by reference to the following Detailed Description, when taken in conjunction with the accompanying simplified drawings of exemplary embodiments. The illustrative, schematic drawings, briefly described here below, are not to scale, are presented for ease of explanation and do not limit the scope of the inventions recited in the accompanying patent claims.

The following non-limiting detailed descriptions of examples of embodiments of the technology may refer to appended drawing Figures and are not limited to the drawings, which are merely presented for enhancing explanations of features of the technology. In addition, the detailed descriptions may refer to particular terms of art, some of which are defined herein, as appropriate and necessary for clarity.

In the specification and claims, the terms "compacted," "close packed" and "settled" in reference to a charge of particulates means that the charge of particulates has been treated by shaking up and down, such that the particulates are oriented relative to each other in a closer packed relation than prior to compaction treatment. In the event of fragile or brittle charges, such as some particulate snack foods, the vigor of the compaction treatment should be such as to reduce any breakage to consumer acceptable levels. The shaking that minimizes breakage of fragile particulates, such as some snack foods is referred to herein as "gentle" shaking. This is readily determined by observation and cured by adjustment of frequency and/or amplitude of shaking. By treatment to compact the charge, the volume that the charge occupies is reduced; i.e. the bulk density increases. As a result, a smaller package or bag can be used to contain the charge, than could be used with a non-compacted charge. This results in savings in packaging material, reduced carton sizes for containing the packages, fewer transportation trips to distribute the cartons (saving fuel, and reducing carbon footprint), and reducing landfill needs for waste disposal of used packages. Accordingly, applying a treatment that close packs the particulate charges to the VFFS for packaging presents several advantages.

An issue that arises once a charge enters the top of the film former tube, is that as the charge falls under gravity within the former, the charge becomes more dispersed, and less close packed. Accordingly, for a given mass of the charge, its volume increases (and its bulk density decreases). Improving compaction in the packaging apparatus is a significant goal in order to meet at least some of the advantages detailed here above.

On the other hand, when an already compacted charge enters the top of the film former tube, as the charge falls under gravity within the former, the charge loses at least some of its degree of compaction, so that its volume increases (and its bulk density decreases). Maintaining compaction, or at least minimizing the loss of compaction of the charge is a significant goal in to meet at least some of the advantages detailed here above.

The invention provides a VFFS apparatus and method of using the apparatus that includes a former and associated film driver that reciprocates up and down in a controlled manner such that a charge of particulates in a partially formed bag (i.e. one not yet sealed at the top) below the former undergoes shaking that induces settling (close packing), while the packaging film travels downward continuously. The particulates are more compact (higher bulk density) than it would have been but for the former reciprocation. In accordance with the invention, this allows the use of smaller packages ("bags") thereby using less packaging material, and the resultant savings in waste disposal, fuel, and reduction in carbon footprint, set forth above.

<FIG> depicts schematically a prior art VFFS, which is described here above. <FIG> depicts schematically the components of the VFFS <NUM> that is being used to make a bag <NUM>, that has a bottom seal <NUM> in place and an upper seal <NUM>, formed by the heat bars <NUM> of seal jaws <NUM>. The outlined sections A, and (optionally) B, are in reciprocal motion, according to exemplary embodiments of invention. As indicated at A, the former <NUM>, its associated side seal apparatus <NUM>, and the packaging film drivers <NUM> all reciprocate in concert. Thus, they are invariant in their displacement relative to each other.

As indicated at B, the sealing jaws <NUM> also reciprocate in concert with the former <NUM> and the packaging film drivers <NUM>.

Further, if necessary and/or desirable the packaging film supply including the drive roller <NUM> may also reciprocate synchronously with the former <NUM> and the film drivers <NUM>.

In the exemplary embodiment of <FIG>, there is schematically presented a mechanical detail of an example in accordance with the invention. Other mechanical means can, of course, also be used to cause the desired reciprocation discussed herein. <FIG> shows a motor-driven actuator <NUM> which moves a plate <NUM> that is mechanically attached to the former <NUM>, up and down, in a controlled manner. Controller <NUM> controls the direction, speed and frequency of reversal of direction of motor <NUM>. The motor <NUM> is operatively coupled to drive the actuator <NUM>, which includes a pair of grasping hooks <NUM> that lift or descend, depending upon the direction of turning of motor <NUM>. The grasping hooks <NUM> are mechanically coupled to an attachment <NUM>, by one hook facing each outboard side of the attachment. A pin <NUM> passes through the attachment <NUM> of plate <NUM>. Each of the grasping hooks <NUM> is able to rotate about the pin <NUM> as the grasping hooks move up and down, and as a result moves the plate <NUM> up and down. Since plate <NUM> is fixedly coupled to former <NUM>, the former <NUM> moves up and down along with the plate <NUM>. In addition, as indicated with reference to A at <FIG>, the film drivers <NUM>, which are associated with the former <NUM>, move in concert with the former <NUM>. To facilitate this, the film drivers <NUM> may also be mechanically coupled to the support structure that moves in concert with the former <NUM>. So, in operation, the film <NUM> moves continuously around the former <NUM> and downward, as indicated by arrow <NUM>, uninterrupted by the reciprocating motion. Thus, the packaging film does not "pulse" in its smooth, continuous downward travel, relative to the former <NUM>. As indicated above, in reference to <FIG>, the portion A of the apparatus includes the side seal <NUM>, which also moves in concert with the former <NUM>. The side seal <NUM> may be mechanically coupled to the plate <NUM>, or to other support structure that moves with the former <NUM>.

Moreover, as previously indicated at B of <FIG>, the jaws <NUM> move up and down in concert with the former <NUM>.

In some embodiments, a minimum distance between the lower end of the former <NUM> and the sealing jaws <NUM> is maintained during the up and down movement of the former and the sealing jaws. This minimum distance permits tuckers to be inserted to shape the packaging film exiting off the base of the former for making a formatted bag, while the packaging film moves continuously and smoothly downward through the apparatus without interruption.

The transmitting of an up and down reciprocating motion from the former to the partially formed bag such that the charge in this partially formed bag is shaken to allow settling and increase in bulk density. This increase in bulk density allows a smaller bag for packaging the same mass of particulates.

The foregoing exemplary apparatus is not limiting of the invention, and the examples may be modified in a variety of ways to achieve the controlled up and down reciprocation. Conventional VFFS apparatus may readily be retrofitted to practice the technology herein described to obtain (at least) the benefits set forth here. All modifications are within the scope of the invention, as claimed here below. The VFFS apparatus of the invention is flexible, and can be used with a variety of packaging operations and types of bags. For example, it can be used with the typical pillow bag, as well as with large pillow bags. And, it can be used in making formatted bags, including but not limited to, single sided gusseted bags, or double sided gusseted bags, or bags with a flat base shaped for standing upright for display. In some cases, it may be advantageous to maintain a controlled distance between the former and the sealing jaws, for example to allow insertion and removal of tuckers for making formatted bags without interference with sealing jaw operation.

Claim 1:
A vertical form fill and seal apparatus (<NUM>) for packaging a particulate charge, the vertical form fill and seal apparatus comprising:
a former (<NUM>) configured for wrapping a packaging film (<NUM>) around an outside surface thereof and for receiving a particulate charge therein;
a film driver (<NUM>) associated with the former to continuously move the packaging film down around the former without interruption;
an actuator (<NUM>) in mechanical communication with the former and the film driver (<NUM>), wherein the actuator (<NUM>) applies a vertical reciprocating force to the former (<NUM>) and the film driver (<NUM>) to move both the former (<NUM>) and the film driver (<NUM>) up and down synchronously while the film driver (<NUM>) continuously and without interruption moves the packaging film down around the former (<NUM>);
sealing jaws (<NUM>) located below the former and that move up and down in concert with the former to transversely seal packaging film exiting off the former to form a bag (<NUM>) containing the particulate charge, when the apparatus is in use; and
a controller (<NUM>) in communication with the actuator and configured to control a frequency and amplitude of the reciprocating force applied by the actuator;
whereby when in use, the synchronous reciprocal motion of the former and the film driver causes shaking of particulate contents in a partially formed bag below the former, the shaking causing settling of the particulate contents in the partially formed bag to increase a bulk density of the particulates.