Shouldered Wickets

Abstract

A shouldered wicket for holding a stack of flat flexible articles such as plastic packaging bags or sheets which are to be removed one at a time from the top of the stack, the shoulder portions of the wicket extending upwardly above the rest of the wicket to facilitate article removal from the wicketed stack.

Description

The present invention relates to wickets for holding stacked supplies of flat flexible articles which are to be dispensed or removed from the stacks either manually or automatically one at a time for utilization and more particularly to wickets for holding stacked supplies of flattened flexible plastic packaging articles such as bags or wrapping sheets in readiness for removal and use at industrial packaging stations.

Packaging operations in industry are of significant import and interest towards promoting the rapid, efficient and economical packaging of products for the market. Food packaging generally and the meat packing industry in particular require additionally the strict maintenance of sanitary conditions. Automatic or semiautomatic packaging techniques have been developed towards achievement of these desired goals. Semiautomatic packing techniques, that is to say those requiring the cooperation of a human operator with a machine, are uniquely of interest to the meat packing industry since the products being packaged frequently are not exactly alike as to size, shape and weight, a circumstance militating against fully automatic packing. To the extent that food products, meat cuts and the like for example, are at least sufficiently alike in size, shape and weight in a given series to permit the use of packaging bags or wrapping sheets of the same size and material, some degree of automation in the packaging operation is possible. U.S. Pat. No. 3,552,090 to Roberts et al and the copending application of Kupcikevicius et al, Ser. No. 173,960, assigned to the same assignee as this application are illustrative of such semiautomatic techniques and apparatus. To a much lesser degree, the automatic part of a packaging process may take the form of relatively facile availability on one bag or wrapping sheet at a time from a bag supply source.

Here it should be noted that while the ensuing discussion treats of packaging bags towards illustrative simplification, this invention applies equally as well to stacked wicketed wrapping sheets and the like and indeed more generally has full applicability to any stacked wicket-held flat flexible articles which are to be dispensed one at a time.

Whatever the degree of complexity of the apparatus and techniques employed in a packaging operation involving food, meat products in particular, it is of the utmost importance that the supply of packaging bags be maintained in a sanitary condition and that the bag dispensing action be accomplished with facility and without bag waste or the incidental production of torn bag scraps which interfere with smooth and efficient operation. While these desirable characteristics are very important in even the simplest modes of semiautomatic packaging, they are of much greater importance in the more fully automated modes such as for instance those involving opening the bags one at a time with an air stream for insertion of a product unit into each bag sequentially. In these more automated techniques the relatively higher packaging speed necessitates a sanitary, continual and consistently reliable bag supply arrangement and towards attaining these desiderata the wicket which holds the stacked supply of bags in place on the apparatus or at the packaging station is a significantly important element in the operation. Bags for such use, irrespective of the complexity of the particular packaging technique, may be supplied to the user in bulk packages which are opened and the bags loaded by hand into the bag dispensing station or portion of the apparatus or in prewicketed packages such as described in the copending application of Cwikla, Ser. No. 213,755, assigned to the same assignee as this application.

The wickets, whether they are parts of an automatic packaging apparatus or simple bag supply holder device or are furnished along with the packaged prewicketed bags, are as stated above, extremely important elements in these packaging operations as will be readily appreciated by persons familiar with the art.

Criteria for wicket design dictate that each bag in turn atop a stack of wicketed bags at a packaging station must be readily removable without the incidental production of bag scraps and with clean direct tears through the bag material from the wicket holes to the outer open edge of each holed ply of the bag.

Known wickets used to hold stacked bag supplies in the aforedescribed manner are best described as inverted U-shaped with the U having a flat bottom which, with the wicket in place, spans across the top bag of the stack along a line between the wicket holes to define a horizontal bearing member. This horizontal bearing member is caused, by one means or another, to exert vertical downward bearing pressure on the stacked bags, keeping them substantially in registering relationship as between themselves and with other functional elements at the packaging station. Such known wickets have presented difficulities in causing random tears with consequent unuseable bags and in the unwanted production of bag scraps with attendant dangers of contamination of the articles being packaged. While the exact reasons for the faults of these known prior art wickets are not germane to the discussion here, the faults themselves being clearly manifest, it is thought that the pinching action on the bag stack at the interior right angles at the junctures of the wicket legs and the horizontal bearing member cause stresses and restraint holding forces which exceed the elastic limits and tear resistance of the bags at locations other than where the tears are intended during the action of pulling a bag from atop the stack. In any case these problems exist and are real and very serious in industry.

One quickly suggested and initially apparently good solution which, upon inspection and test does not solve the problem, is to modify the horizontal bearing member of the wicket to a raised or upwardly disposed arcuate form. This of course effects loss of the vertical downward stack restraining pressure which is essential, particularly in semiautomatic or automatic operations, and also creates interference with insertion into the still wicket-held bag of the article being packaged. Alternative suggested and tried solutions to the problems along these lines and along others as well, have been less than successful and, up to the time of the present invention, no reasonably satisfactory bag holding wicket has been available to the packaging arts.

With this as the state of the art, the present invention was concieved and reduced to practice with the object of providing a wicket to hold stacked flat flexible articles and to permit facile one at a time removal of the articles from atop the stack without damage to the articles.

It is a more particular object of this invention to provide a wicket which holds flattened stacked flexible plastic packaging bags in place at packaging station and permits the repetitive, rapid removal of bags one at a time from atop the stack for use in packaging operations.

A still further and important object of the present invention is to provide a wicket which is particularly suitable for use in conjunction with automatic and semiautomatic packaging apparatus where the packaging operation proceeds at sustained relatively high speeds.

These and other objects of the invention will become more readily apparent from the ensuing description and the appended drawings wherein:

FIG. 1 shows a wicket according to the present inventions in place in a sectional view through a typical semiautomatic packaging apparatus.

FIG. 2 shows a frontal view of an alternative wicket embodiment according to the invention.

FIG. 3 is a side view of the FIG. 2 embodiment.

FIG. 4 is a top view of the FIG. 2 embodiment.

FIG. 5 is a frontal view of another alternative embodiment of a wicket according to the invention.

FIG. 6 is a side view of the FIG. 5 embodiment.

FIG. 7 is a top view of the FIG. 5 embodiment.

FIG. 8 is a plan or top view showing a possible modification to any of the wicket embodiments according to the invention.

In general, the present invention comprehends a wicket for holding a stack of flat flexible articles provided with paired holes to accommodate wicket leg members, which articles are to be removed one at a time from the stack, said wicket comprising, in combination; a horizontally extending bearing member adapted to apply a vertical restraining force to said stack spaced from said holes and having a bearing contact span on the topmost article of the stack at maximum equal to the linear distance between the paired holes plus two hole diameters; leg members extending vertically each respectively through the paired holes in the stack adapted to maintain the individual articles therein and the holes in substantially registering relationship, said wicket leg members having free ends adapted to extend insertably into wicket mounting means and; shoulder members each having a first element connected to and extending upwardly from an end of the bearing member, a second element connected to and extending upwardly from an upper end of a leg member, and connecting means between the first element and the second element.

In one typical embodiment of apparatus according to the invention, the horizontally extending bearing member is adapted to bear on the topmost article of the stack along a line between the paired holes.

In certain alternative embodiments the horizontally extending bearing member is adapted to bear on the topmost article of the stack only partly on a line between the paired holes.

In other alternative embodiments of apparatus according to the invention, the horizontally extending bearing member is adapted to bear on the topmost article of the stack on a locus other than a line between the paired holes.

In still other alternative embodiments, the horizontally extending bearing member is adapted to transmit a vertical restraining force to said stack and to bear on the topmost article of the stack for a total distance less than its overall horizontal span.

Any and all of the embodiments of apparatus according to the present invention may be fabricated from rod-like stock elements, and, in most instances, advantageously may be connectedly and integrally formed from a unitary rod-like element.

With reference to the drawings, FIG. 1 shows, in a sectional view through a semiautomatic packaging apparatus, a wicket according to the present invention in place holding a stack of flattened flexible plastic bags 11, with a topmost bag 13 of the stack opened, by an air stream for instance, and in readiness to receive an article to be packaged. The wicket shown comprises a horizontally extending bearing member 15 which is adapted to apply vertical restraining force directly on the lower ply of bag 13 and to the bags 11. This vertical restraining force may be applied to the bearing member and/or to other parts of the wicket by loading the wicket with a pivotally cantilevered air nozzle 12 of the packaging machine such as is illustrated in greater detail in the Kupsicevicius application supra.

As shown in the drawing, wicket leg members 23, 25 extend vertically each respectively through holes 27, 29 in the stacked bags 11 and are mounted insertably in suitable holes in a wicket base 21, holding the stacked bags in substantially registering relationship.

Upwardly extending shoulder members are disposed between the bearing member 15 and respective leg members 23,25, each shoulder member comprising respectively, a first element 31,33 extending upwardly from an end of the bearing member 15, a second element 35,37 extending upwardly from the uppermost portion of each leg member 23,25, and connecting means 39,41 joining respective first and second elements. In the illustrated embodiments, as in the case of practically all wickets made according to the present invention, all of the wicket members and elements may be connectedly and integrally formed from a single piece of suitably heavy gage wire or rod stock, usually some kind of metal such as steel or stainless steel.

This shouldered wicket structure, it has been found, relieves the wicketed bags of troublesome stress concentrations at the bag holes and permits direct clean tears of each topmost bag in turn from the wicket from the holes to the bag outer edge, a feature particularly important in the use of so-called arc-mouthed bags where the holed lower ply of each bag is wicket-held while an arcuitely deep-cut upper ply is left free of the wicket to be readily opened for insertion of an article being packaged. At the same time, nevertheless, the horizontally extending bearing member applies sufficient downward force to the topmost bag lower ply and the stacked bags therebeneath to maintain the bags in satisfactory registration for cooperation with other functional elements in the packaging operation.

In its most elemental form the shouldered wicket according to the present invention has all its parts substantially in the same vertical plane and is called an M wicket.

FIGS. 2, 3 and 4 of the drawings show an alternative form of wicket, respectively in frontal, side and top views, wherein the upwardly extending shoulder members are in the form of loops, but which may nevertheless be identified, part by part, with the wicket of FIG. 1. FIGS. 2, 3 and 4 show a wicket having a horizontally extending bearing member 115, leg members 123, 125, extending vertically each respectively through holes 127, 129 in stacked bags 111, each loop form shoulder member comprising respectively, a first element 131, 133 extending upwardly from an end of the bearing member 115, a second element 135,137 extending upwardly from the uppermost portion of each leg member 123,125 and connecting means 139,141 joining respective first and second elements.

The looped M wicket, which this variation is called, permits of a greater bearing surface contact on the bags than is possible with uniplanar M wickets as can be seen particularly from the top view, FIG. 4.

In FIGS. 5, 6 and 7 of the drawings, a further style of looped M wicket, called the canted loop M wicket, is shown respectively in frontal, side and top views. All of the members and elements as shown, 215, 223, 225, 231, 233, 235, 237, 239 and 241 are cooperatively arranged as in the FIGS. 2, 3, 4 looped M wicket but wherein the shoulder loops are canted outwardly of the legs. This arrangement is found to be particularly useful where the bag wicket holes 227, 229 are edge reinforced, since greater free clearance obtains between the hole edges and bearing contact line of the horizontally extending bearing member 215.

FIG. 8 shows in top or plan view a further alternative feature which is applicable to any of the wicket embodiments according to the invention. This alternative structure comprehends a horizontal bearing member 315 which has a bearing locus on the stack bags other than anywhere coincident with a line between the paired holes 327, 329. This wicket design, it has been found, is particularly appropriate in effecting bag lower ply edge restraint in operations involving air-opening of the bags and, as noted, is adaptable to all embodiments of wickets according to the present invention.

In all of the wickets, the bearing contact span length on the topmost bag of the bag stack is, at its maximum, equal to the linear distance between the outermost edges of the paired holes or, in other words, the linear distance between the innermost edges of the paired holes, plus two hole diameters. By bearing contact span length is meant the overall straight linear distance measured across the planform view of any given horizontal bearing member, irrespective of its length as fully traversed.

Wickets of the embodiments and styles described have been made from metal rod stocks and relatively heavy gage wire and tested with consistently excellent and reproducible results.

Other forms of wickets within the scope and spirit of this invention will, in the light of this disclosure, undoubtedly occur to persons familiar with the art. It is therefore intended that this disclosure be deemed illustrative only and not construed in any limiting sense.

Claims

What is claimed is:

1. A wicket for holding a stack of flat flexible articles provided with paired holes to accommodate wicket leg members, which articles are to be removed one at a time from the stack, said wicket comprising, in combination,

a. a horizontally extending bearing member arranged and disposed to apply a vertical restraining force to said stack and having a bearing contact span length on the topmost article of the stack at maximum equal to the linear distance between the paired holes plus two hole diameters,

b. leg members extending vertically through the paired holes in the stack each respectively adapted to maintain the individual articles therein and the holes in substantially registering relationship, said wicket leg members having free ends adapted to extend insertably into wicket mounting means, and

c. shoulder members each having a first element connected to and extending upwardly from an end of the bearing member, a second element connected to and extending upwardly from an upper end of a leg member, and connecting means between the first element and the second element.

2. A wicket according to claim 1 wherein the horizontally extending bearing member is adapted to transmit a vertical restraining force to said stack and to bear on the topmost article of the stack for a total distance less than its overall horizontal span.

3. A wicket according to claim 1 wherein the horizontally extending bearing member, the leg members and the shoulder members are connectedly and integrally formed from a unitary rod-like element.

4. A wicket according to claim 1 wherein the horizontally extending bearing member has a bearing contact span length on the topmost article of the stack less than the linear distance between the paired holes.

5. A wicket according to claim 4 wherein the horizontally extending bearing member, the leg members and the shoulder members are connectedly and integrally formed from a unitary rod-like element.

6. A wicket according to claim 4 wherein the horizontally extending bearing member is adapted to bear on the topmost article of the stack along a line between the paired holes.

7. A wicket according to claim 6 wherein the horizontally extending bearing member, the leg members and the shoulder members are connectedly and integrally formed from a unitary rod-like element.

8. A wicket according to claim 1 wherein the horizontally extending bearing member is adapted to bear on the topmost article of the stack only partly on a line between the paired holes.

9. A wicket according to claim 8 wherein the horizontally extending bearing member, the leg members and the shoulder members are connectedly and integrally formed from a unitary rod-like element.

10. A wicket according to claim 1 wherein the horizontally extending bearing member is adapted to bear on the topmost article of the stack on a locus other than a line between the paired holes.

11. A wicket according to claim 10 wherein the horizontally extending bearing member, the leg members and the shoulder members are connectedly and integrally formed from a unitary rod-like element.