Walking Beam Bag Loader

The invention disclosed herein relates generally to the art of loading articles into containers and more particularly to a method and apparatus for loading fresh meat articles into flexible plastic containers. Meat articles have conventionally been manually loaded into flexible plastic packages for either shipment or display. While many aspects of meat packaging process had been refined to a high degree of automation, the actual step of placing meat articles into containers has remained a substantially manual operation wherein an operator receives the cut of meat from a conveyor, selects an appropriately sized container and slides the meat from a shelf into the container. The subsequent processing steps of vacuumizing, clipping and shrinking are highly automated but remain dependent upon being supplied from a manual container loading step.

An attempt to overcome the shortcomings of prior art manual handling of meat cuts is described in U.S. Pat. No. 3,942,624 to Kupcikevicius issued Mar. 9, 1976. The apparatus described therein is a bag loading apparatus which comprises a cantilevered conveyor system such that a meat article may be placed on one end of the conveyor while a bag is draped around the cantilevered end of the conveyor. The movement of the conveyor causes the meat section to move along the conveyor. While this apparatus overcomes many of the shortcomings of the prior art, it utilizes a plurality of conveyor belts which by necessity are grooved or otherwise roughened so as to prevent any sliding during the conveying process.

In the meat handling art it is necessary to maintain extremely sanitary surfaces and the use of grooved conveyor belts is not conducive to such sanitary conditions. Another shortcoming of this device is the problems associated with tracking and maintaining parallelism of the cantilevered conveyors. An additional problem with this prior art device is associated with breakdown in a meat packaging line. Inevitably breakdowns and power failures occur, and due to the nature of the belts, meat articles must be carried across the conveyor for packaging; thus effectively causing a breakdown and bottleneck in the entire meat packaging line.

It is thus an object of this invention to provide a new method and apparatus for conveying and loading articles into containers.

It is a further and more particular object of this invention to provide a method and apparatus for loading fresh meat articles into flexible plastic containers.

It is a still further object of this invention to provide a method and apparatus for loading fresh meat articles into containers wherein an operator has to neither lift nor handle meat.

It is yet another object of this invention to provide a method and apparatus for loading fresh meat articles into containers wherein the contacting surfaces are readily cleanable.

It is yet a further and more particular object of this invention to provide a method and apparatus for loading articles into containers wherein belt conveyors are not utilized.

It is yet a still further object of this invention to provide a method and apparatus for loading meat articles into containers which is readily adaptable to manual operation should mechanical breakdown occur.

These, as well as other objects, are accomplished by a walking beam conveyor cantilevered at one end and being operable from two sets of beams. One set of beams is operable to move in a horizontal mode while the other set of beams is operable to move in a vertical mode.

FIG. 1 is an isometric view of apparatus in accordance with this invention.

FIG. 2 graphically illustrates the movement and synchronization of the horizontally and vertically movable beams in accordance with this invention.

FIGS. 3 and 4 depict motion producing means of the apparatus shown in FIG. 1.

FIG. 5 illustrates an alternative embodiment of this invention.

According to this invention it has been found that an apparatus having in combination, a plurality of cantilevered beams divided into two sets, one set of which is movable in a horizontal mode and another set of which is movable in a vertical mode, provides a conveying function to a packaging operation such that varying sized meat articles may be packaged at the end of a cantilevered conveyor without the inconveniences associated with conveyors utilizing conventional belts. Various features and advantages of this invention will become apparent from the following description with reference to the various figures of drawing.

FIG. 1 of the drawings depicts in isometric form a walking beam bag loader cantilevered in accordance with this invention. The apparatus operates in normal walking beam fashion with two sets of beams each set being operable in a different dimensional mode. The apparatus 1 of FIG. 1 is comprised of a base portion 3 supporting the movable beam on the upper portion thereof. The beams are of two types. Beams represented by numerals 5, 7, 9 and 11 are operable in the horizontal mode while beams represented by numerals 13, 15 and 17 are operable in the vertical mode. The horizontally movable beams reciprocate in a horizontal plane while the vertically movable beams reciprocate in a vertical plane. The relative coordination of the two movements is such as to produce a forward motion of an article resting on the upper beam surfaces.

FIG. 2 of the drawings depicts in graphical fashion the desired synchronization of the two movements. The Figure illustrates with a solid line the movement of the horizontal beams. Thus when the solid line curve moves in the upward direction the horizontal bars are moved forward, and when in the downward direction, the horizontal bars are moving in the reverse direction. The broken line illustrates the movement of the vertically movably beams such that when the broken line is moving upwardly, the vertical beams are moving toward the elevated position. Conversely when the broken line is headed in the downward direction the vertical beams are moving toward the depressed position. The abscissa, which represents time in arbitrary units, at the zero position represents the plane of the horizontally movable beams for the vertically movable beams and the midway travel point for the horizontally reciprocal beams, i.e., a point halfway between the forward and reverse extent of reciprocal movement. Thus as the horizontally movable beam moves forward to the extent of its forward position, the vertically movable beams are below the plane of the horizontally movable beams. At the end of the forward extent of horizontal movement, the vertically movable beams rise through the plane of the horizontally movable beams to lift a conveyed article above such plane while the horizontally movable beams reciprocate to the reverse position. As the horizontally movable beams reach the end of the reverse extent to again move forward, the vertically movable beams move to a depressed position beneath the plane of the horizontally movable beams, such that an article rests on the horizontally movable beams during the forward motion thereof. Such movement continues in a cyclic fashion to convey an article resting on the surface of the beams in a forward direction, i.e., a direction of desired article progression.

The rate of article progression can be readily controlled by controlling the amplitude and frequency of the horizontally movable beams. For example, an amplitude of eight inches at 96 oscillations per minute would give a forward speed of 64 feet per minute. It is desirable to have a large amplitude so as to reduce the number of starts per unit of conveyed distance.

While many mechanical arrangements may be utilized to bring about the motion described above for the walking beam bag loader, a preferred construction is illustrated in FIGS. 1, 3 and 4 wherein but a single power generating means is utilized to provide both the horizontal and vertical motion. FIGS. 3 and 4 provide detail as to the operation. For purposes of simplicity only two horizontally movable beams 19 and 21 and one vertically movable beam 23 are shown in FIG. 3 of the drawings. As is readily apparent from this figure the vertically movable beam operates from a rotatable cam 25 which provides the vertical movement required of the beam 23. Cam 25 is operable by power source or motor 27 shown in FIG. 4 of the drawings. Roller 29 communicating with vertical shaft 31 is operable for reciprocating beam 23 in a vertical plane upon rotation of cam 25.

Also associated with rotatable cam 25 is a vertical beam 33 which rides within a slot 35 of a support beam 37 attached to horizontally reciprocal beams 19 and 21. Upon rotation of cam 25 vertical beam 23 riding within the slot 35 communicates a horizontal reciprocating movement to horizontally movable beams 19 and 21. It is understood that various associated support and stablizing devices may be incorporated into this structure. One such device for stablizing the vertically movable beams is illustrated in FIG. 4. The rear portion of vertically movable beam 23 has a stabilizing rod 39 which rides within cylinder 41 for purposes of stablizing the motion of the vertically reciprocal beam. In a like manner the horizontally movable beams are stabilized by attaching support beam 37 to tracks 43 and 45 as illustrated in FIG. 1 of the drawings.

It is readily apparent, however, that various other mechanical devices well within the skill of the art could be utilized to provide requisite motion. For example, the vertically movable beams may be operated totally independently of the horizontally movable beams by separate mechanical means.

In operation it is preferred that the elevation of the vertically movable beam above the plane of the horizontally beams be maintained at one inch or less. It has been found that the greater the elevation the greater the tendency is for conveyed objects to bounce along the conveyor path. For this reason the amount of elevation should be minimal. It is additionally preferred that the lower portion of the vertically movable beams not rise above the plane of the horizontally movable beams as a safety feature to circumvent the possibility of an operator's finger being trapped beneath the surface of the vertically movable beams.

An additionally preferred feature of this invention is the use of scores or tracks along the surface of the horizontally reciprocal beams. These tracks are illustrated in FIG. 3 of the drawings as scores 44 and 46. The use of scores or tracks prevents a conveyed object such as a piece of fresh red meat from sliding on the beams during the conveying process. An unexpected advantage of utilizing scores only on the horizontally reciprocal beams is that in the event of a power failure, the vertically reciprocal beams may be elevated to the elevated position and utilized as a sliding surface. This is a significant improvement over the prior art which had to, during a breakdown or power failure, manually move meat articles without contacting the otherwise non-sliding surfaces of conveying belts.

An additionally preferred feature of the apparatus of this invention is the use of control means for deactivating and activating the operation of power source 27. For this purpose a depressable trigger 47 is illustrated in FIG. 1 of the drawings which deactivates power source 27 upon arrival thereon of a conveyed article. The deactivation of the beams permits an operator to drape an appropriately sized container through and under the appropriate number of beams for receipt of the conveyed article. Preferably a knee actuated lever such as 49 permits the operator to reactive the motor 27 when the container is properly positioned for receipt of the conveyed article.

An alternative embodiment of this invention is shown in FIG. 5 of the drawings wherein beams 51 and 53 are adapted to operate in a swinging fashion such that the beams have both a horizontal and a vertical displacement during operation. Many mechanical arrangements are available for this type of construction. However, the arrangement shown in FIG. 5 is a simple rotational arrangement wherein a reciprocating beams 51 and 53 are attached by vertical supports 55 to a rotating cranks 57. In this arrangement alternate beams are attached to their respective rotating cranks in a manner so as to be 180.degree. out of phase with the immediately adjacent beams. This arrangement also provides for a cantilevered construction to facilitate the loading of a container. This arrangement may also be facilitated by the use of one set of beams having a lesser extent in the direction of progression than the 180.degree. off set counterpart.

This alternative embodiment does not require the use of scores to prevent sliding since the motion of the conveyed article is continuous. This construction provides for a smooth sliding surface in the event of breakdown regardless of beam position.

An additional embodiment within the scope of this invention is a modification of the last discussed embodiment wherein one set of beams is stationary and the other moves with the swinging movement discussed above. In this embodiment the swinging set of beams moves forward while above the plane of the stationary beams and backward while below the plane of the stationary beams. This embodiment is easily visualized from FIG. 5 with alternate beams being immobilized.

While all embodiments discussed above illustrate and describe an arrangement wherein alternate beams operate in a mode different from the next adjacent beams, it is readily understood that if desirable adjacent beams be operable in the similar mode so long as the net effect is to provide conveying action in the desired direction of article progression.

It is thus seen that the method and apparatus of this invention provide a novel technique whereby articles may be conveyed into containers. The method and apparatus of this invention further provide an apparatus which does such conveying without the use of conventional belts and which provides a sliding surface in the event of a power failure while at the same time providing a gripping surface when in operation. Various modifications and alterations will be apparent to those skilled in the art. Such variations, however, are within the spirit and scope of the present invention as is defined by the following appended claims.