Screw conveyor container filling system

An improved container transportation and filling system and method is provided. The system can deliver cartridges and other containers, such as tubes, in a horizontal orientation. The containers can have a closed bottom end and an open top end. A screw conveyor(s) is used to engage the containers and urge them forward and into rotation around the axis of the screw conveyor, from horizontal to vertical. A guide engages an end of the containers. The guide acts as a camming surface and guides the end of the container downward as it is advanced by the screw conveyor, to orient the container vertically for filling, capping and sealing. A second mirror image downstream screw conveyor and guide can reorient the container from vertical to horizontal.

BACKGROUND OF THE INVENTION

The invention relates generally to machines and methods for filling containers, such as rigid and various types of tubes, such as caulking cartridges, with material to be dispensed from those containers. More particularly, the invention relates to an improved system and method for orienting the containers before, during, and/or after they are filled.

A variety of automated processing systems and methods have been employed to deliver storage tubes, bottles and other containers of circular, square or other cross-sectional geometries to a filling station; fill and cap those containers; and then deliver the containers from the filling station. It is typically preferable to dispense material into and fill a container from the bottom up. Therefore, it is typically preferable to fill elongated containers when they are in a vertical orientation. However, the center of gravity of these containers makes them prone to tipping or otherwise makes it inconvenient to transport these containers in the “top-open” upright orientation. Furthermore, cylindrical and cylindrical-like containers are often easily transported by rolling or sliding. Consequently, it is often preferable to transport containers in a horizontal orientation, reorient the containers into a vertical orientation for filling, capping and sealing, and then reorient the containers back to the horizontal orientation for further transportation.

Examples of systems for transporting and filling containers are disclosed in U.S. Pat. Nos. 4,974,755, 6,733,224 and 8,794,275, the contents of each are incorporated herein by reference. These and other systems have not proved to be fully satisfactory in connection with the way the containers are oriented between the vertical and horizontal orientations. This can often lead to inefficient or expensive equipment and/or a slow down the assembly line process.

Accordingly, it is desirable to provide an improved system and method for orienting containers as part of an automated filling process, which overcomes drawbacks of conventional systems and methods.

SUMMARY OF THE INVENTION

Generally speaking, in accordance with the invention, an improved container transportation and filling system and method is provided. The system can deliver containers, such as tubes and tube-shaped cartridges, in a horizontal orientation, wherein the top and bottom ends are pointing sideways. A screw or auger-shaped conveyor, having a helix around a shaft, optionally defined by a spiral ridge having valleys or troughs between the apex of the ridges is provided. This screw conveyor (single, stacked dual screw conveyor or stacked multi-screw conveyor) is used to engage the containers and urge them in the downstream flow direction and into rotation around the axis of the screw conveyor, as the conveyors pivot from a horizontal to a vertical orientation.

A first guide bar rests across the sides of the containers and holds the containers against the screw conveyor. The guide bar permit the containers to slide under the bar and rotate downward from a horizontal to a vertical orientation. A second guide bar or guide rail engages the bottom end of the containers. The guide rail is inclined downward with respect to the axis of the screw conveyor and acts as a camming surface. The guide rail guides the bottom end of the containers downward and downstream as the containers are advanced by the screw conveyor. If the tube includes a nozzle extending from the bottom end of the container, the optional nozzle can help keep the containers in place. A second screw conveyor system can advance the containers through a filling, capping and sealing station. A third downstream screw conveyor can reorient the capped and filled containers from a vertical to a horizontal orientation.

The helix of the screw conveyor can have ridges, with valleys or troughs therebetween, that are the approximate width of the containers. Other configurations can be used, such as a flat helix spiral around a cylindrical shaft or a tight spiral, with close fitting screw threads.

The cross-sectional height of the single screw conveyor or combined height of a multiple stacked screw conveyor should be about 66% to 133%, preferably about 90% to about 110% of the length of the containers. An infeed section preferably includes two screw conveyors, one over the other, to orient the containers from horizontal to vertical. A second screw conveyor section, preferably two screw conveyors, one over the other, can be used to transport the vertical containers through a filling station. An outfeed screw conveyor section, which can be a mirror image of the infeed section, can be used to orient the vertical containers from vertical to horizontal.

Accordingly, it is an object of the invention to provide an improved system and method for filling containers and for transporting containers to, through, and/or from the filling operation.

Still other objects of the invention will in part be obvious and will, in part be apparent from the specification and drawings. The invention accordingly comprises the apparatus and method of operation which will be exemplified in the structures and methods hereinafter described, and the scope of the invention will be indicating the claims.

As used herein, like reference numerals will be used to indicate similar elements. The features depicted in the drawings are not necessarily drawn to scale. The drawings are for purposes of illustration only and should not be interpreted as limiting.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A container filling system preferably delivers the containers in a horizontal orientation in an infeed section; rotates the containers to a vertical orientation for filling in a working section; and can rotate the containers back to a horizontal orientation in an outfeed section. The change from horizontal to vertical (and back), is preferably accomplished with a feed screw conveyor or “a” shaped mechanism, which both advances the containers in a downstream flow direction and provides a surface for them to rotate into and out of the vertical orientation. The screw conveyors can be driven by any known mechanism, such as a belt, gear, chain or other system. The multiple screw conveyors can be linked and driven as a unit or driven separately. In a preferred embodiment of the invention, the screw conveyors are inline and rotate together at the same speed.

A guide bar positioned against the side of the containers holds the containers close to the screw conveyor. A declining guide rail positioned to engage the bottom end of the containers, with the containers resting on the guide rail guides the bottom ends downward and prevents the containers from falling, as they transition from horizontal to vertical. A nozzle extending from the bottom end can help keep the container engaged with the guide rail. The guide rail acts as a camming surface as the bottom end descends into the vertical orientation. A mirror image inclining guide rail can urges the bottom end of the containers upward from the bottom pointing location during the transition from vertical to horizontal. In a preferred embodiment of the invention, dual screw conveyors, one over the other, are used to advance the containers. Using multiple, preferably two screw conveyors is preferred. It can provide a more stable transition between horizontal and vertical orientation and a smaller radius of curvature and therefore shorten the distance needed to curve the containers between the horizontal and vertical orientations.

A container filling system in accordance with the invention can also include a working section. The working section can include machines for filling, capping and sealing the containers. In a preferred embodiment of the invention, the containers are advanced through the working section with single, dual, or multiple screw conveyors. It is preferable that these screw conveyors have the same dimensions as the screw conveyor(s) of the infeed section. It is preferable that the screw conveyors in the working section rotate together with the screw conveyors of the infeed section, to provide smooth downstream flow. They may be linked or driven separately.

The containers can be held against the screw conveyor(s) with a guide bar along their sides and can be supported against falling downward with a guide rail or other support on their bottom end. All the screw conveyors in the system can be linked and driven from the same motor or can be driven by separate motors and/or drives.

A container filling system in accordance with the invention can also include an outfeed section. The outfeed section can be a mirror of the infeed section. Containers are transitioned from a vertical orientation with the bottom end facing downwards, to a horizontal orientation with the bottom end facing horizontally. Preferably, the containers are held against the one or more screw conveyors with a guide bar and urged upward, along the curvature of the screw conveyor(s) with an inclined guide rail, which transitions from below the screw conveyor to alongside the screw conveyor.

Container filling systems in accordance with the invention can include gravity feeds, wherein containers can roll or slide down a ramp into the infeed section. They can also include gravity outputs, where containers can roll or slide from the outfeed section. They can also be urged into the infeed screw conveyor and out of the outfeed screw conveyor by using a powered belt conveyor or drive belts.

A container filling system in accordance with preferred embodiments of the invention is shown generally as an inline: filler100inFIG. 1. Inline filler100includes an infeed section200, a working section600, and an outfeed section900.

In-line filler100is constructed to receive a plurality of unfilled cartridges110. Unfilled cartridges110are elongated and have an open top end127and a closed bottom end123. A container section120having a side surface122along its length, extends from top127to bottom123. A nozzle portion121extends from bottom end123.

Unfilled cartridges110are advanced downstream to working section600, where material is delivered into container section120at a filling station610to form a filled cartridge111. Filling station610can comprise any conventional or improved filling station as known in the art. It can include a metered cylinder which received a metered amount of material and a piston for dispensing the material into container section120. Filled cartridges111are then advanced downstream to closing station620. Closing station620can include a plurality of caps or other closures, and install those caps over open top end127, to enclose the material within container section120. Closing station620can also include crimping devices and/or thermal or sonic welding devices to seal the cap to top end127, to form a sealed cartridge112. In-line filler100also includes a control panel150for adjusting the speed at which cartridges110,111, and112advance, as well as the filling and capping conditions.

Additional details of infeed section200are shown inFIGS. 2-5. Unfilled cartridges110are delivered with a horizontal infeed ramp210. Infeed ramp210includes a pair of guide rails211and212, which are spaced slightly wider apart than the length of container portion120. This helps deliver unfilled cartridges at the proper position.

Infeed section200also includes a cartridge transition section230, including a top infeed screw conveyor231and a bottom infeed screw conveyor232. Screw conveyors231and232include a helix having a plurality of ridges235and concave valleys236between ridges235. Ridges235can be the approximate width of container portion120and valleys236can have the approximate curvature of container portion120. The tops of the ridges can by pointed or flattened. The depth of the valleys should be about 25% to 50% of the diameter of the containers. The screw conveyors can be formed of a variety of materials, preferably UHMW, Delrin and the like or a coated Aluminum, depending on the application.

A combined cross-sectional height of screw conveyors231and232(or the cross sectional height if one screw conveyor is used) should be about 66% to 133%, preferably about 90% to about 110% of the length container portion120.

Infeed ramp210includes a bottom ramp end215. At bottom ramp end215, cartridges110enter transition section230. There, empty cartridges110are held against screw conveyor231and/or screw conveyor232by a guide bar241, which acts as a camming surface. Bottom end123of cartridges110rests against a declining guide rail242, which is angled downward and guides bottom end123downward from its initial orientation pointing horizontally, to a final orientation pointing vertically downward.

As empty cartridges110enter transition section230and contact top screw conveyor231, they are urged downstream in forward direction A. Screw conveyors231and232rotate in the direction of circular arrow B. Based on the helix configuration of ridges235and valleys236, this rotation of screw conveyors231and232advances cartridges in the downstream direction of an arrow A. This rotation also urges cartridges110in the outward direction of an arrow C. However, movement of cartridges110in direction C is restrained by the camming function of guide rail242, which acts as a camming surface against bottom end123. In addition, side surface122of cartridges110first contacts top screw conveyor231at a location more than half of the distance from bottom end123, such that the center of gravity is outside screw conveyor231. Thus, gravity will also urge bottom end123of cartridges110to rotate downward (rotation of a circular arrow B). In its final orientation, bottom end123and nozzle121point downward and open end127points upward in the direction of an arrow D.

Infeed section200has an exit end292, with empty cartridges110in a vertical orientation, with open end127pointing upward. After passing exit end292, empty cartridges110enter an entrance end691of a container transportation section650of working section600. Container transportation section650is shown inFIGS. 6-9. Container transportation section650includes an upper transportation screw conveyor631above a lower transportation screw conveyor632.

The screw conveyors described herein are preferably formed as a single piece. It is preferred that transportation screw conveyors631and632have the same dimensions and rotate at the same speed with infeed screw conveyors231and232of infeed section100. They can all be driven by the same actuator and can be linked together or by separate devices.

Transportation screw conveyors631and632are configured similarly to infeed screw conveyors231and232, with a helix defined by ridges635and valleys636. Transportation screw conveyors631and632also rotate in the circular direction of arrow B. Screw conveyors631and632urge empty cartridges110in downstream direction A to filling station610, comprising two filling machines611and612where they are filled with a selected amount of material and become filled cartridges111. Optionally, one, two three, or more filling stations are acceptable. Filled cartridges111are then urged downstream flow direction A, to two capping and sealing machines621and622of closing station620. Filled cartridges111are capped and the cap is sealed to container section120, to create capped and sealed cartridges112. Optionally, one, three, or more capping and sealing machines are acceptable. A pair of working section guide bars641aand641b(FIG. 6) hold cartridges110,111and112against transportation screw conveyors631and632as they proceed through container transportation section650. Bottom ends123slide on a horizontal transportation guide bar (not shown).

At an exit end692of container transportation section650, filled, capped and sealed cartridges112are delivered to outfeed section900, also shown inFIGS. 10-13. Bottom end123rests against an inclining guide rail942with cartridge112in an initially vertical orientation. A pair of outfeed screw conveyors931and932rotate in the direction of arrow B and urge cartridges112in flow, direction A.

Inclined guide rail942is inclined in the upward direction of arrow D and acts as a camming surface to lift bottom end123and to rotate filled cartridge112into a horizontal orientation. Cartridges112are held against screw conveyors931and932by guide bar941. Thus, as cartridges112proceed in downstream flow direction A, they are rotated from the vertical configuration to the horizontal configuration.

In one embodiment of the invention, outfeed screw conveyors931and932rotate in the same direction as infeed screw conveyors231and232. They can also rotate in the same direction as transportation screw conveyors631and632. Therefore, the rotation of cartridges112from a vertical orientation to a horizontal orientation is opposite to and overcomes friction of outfeed screw conveyors931and932, which are urging the cartridges back into the vertical orientation. In another embodiment of the invention, screw conveyors931and932rotate in the opposite direction of screw conveyors231and232, such that friction urges filled cartridges112into the vertical-to-horizontal orientation. In this configuration, the angle of the helix is also opposite, so as to continue to urge cartridges112in downstream flow direction A.

Filled, capped and sealed cartridges112are delivered to an outfeed exit992, to an exit ramp910. Here, gravity feeds cartridges112down ramp910. Depending on their shape, the containers can roll, slide or be transported by a conveyor belt. Thereafter, they can be boxed and shipped.

Container filling systems in accordance with the invention are particularly well suited for dispensing metered amounts of a high viscosity material, such as caulk, adhesive, putty, peanut butter, paint and so forth. For example, materials having a viscosity over 10,000 cp, preferably over 50,000 and even 100,000 cp. On the other hand, it can be used to dispense metered amounts of many different types of material, regardless of viscosity.

Note that in certain preferred embodiments of the invention, the use of a screw conveyor to transport the containers can be used in one, two or all three of the infeed section, container transportation section and outfeed section independently. That is, for example, a screw conveyor can be advantageously used in the container transportation section even if is not used in the infeed or outfeed sections. For example, it can be used as an advantageous device for advancing containers, whether or not it is used to orient or re-orient the containers. Likewise, a screw conveyor can be used in the outfeed section whether or not it had been used in the infeed or transportation sections. Moreover, a screw conveyor can be used in an infeed or outfeed section even if it is not used to orient or re-orient the containers.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and, since certain changes may be made in carrying out the above method and in the compositions set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.