US3243937A - Apparatus for expanding bags - Google Patents

Description

April 5,1966 RQRAGAN 1 3,243,937

APPARATUS FOR EXPANDING BAGS Filed Nov. 5, 1962 2 Sheets-sheaf, l

INVENTOR ROBERT O. fFAGA/V ATTORNEY j! if April 5, 1966 R. o. RAGAN APPARATUS FOR EXPANDING BAGS 2 Sheets-Sheet 2 Filed Nov. 5, 1962 L--Z7\ 1 F70. 7

United States Patent 3,243,937 APPARATUS FOR EXPANDING BAGS Robert O. Rag'an, Oak Park, 111., assignor, by mesne assignments, to Waldorf Paper Products Company, St. Paul, Minn., a corporation of Minnesota Filed Nov. 5, 1962, Ser. No. 235,225 13 Claims. (Cl. 53384) This invention relates to an improvement in method and apparatus for expanding bags and deals particularly with a method of automatically squaring up the closed ends of bags, and an apparatus for carrying through the method.

Many products are merchandised in bags which may or may not have transparent portions so'that the contents may be viewed. While such bags are often times filled automatically and are often automatically closed, they are usually set up by hand, as a rather complicated mechanism is usually required to feed each bag into an apparatus capable of expanding the bag and forming the square end thereon. While a semi-automatic mechanism may he used, it is usually just about as easy for the operator to expand the bag manually as to place each individual bag on the expanding apparatus. Thus the cost of the paci aging operation is quite materially increased by the labor costs involved in opening the bags.

I have found that if the series of bags are formed by applying a spot of adhesive near the mouth of the bags and between adjacent superimposed bags, the bags may be handled with comparative ease. The bags are shipped and stored in a flat shape in the usual manner. However, when the end bag of the series is grasped and pulled away from the others, the bags tend to fold open much in the manner of a bellows of an accordion, the pulling action of each bag acting to open and expand the next adjacent bag. With this arrangement, the bags form a connected chain and the bags may be readily fed into position over spaced mandrels mounting on a moving conveyor. The mandrels are of the expandable and contractable type, so that after the bags are mounted upon the mandrels, the mandrels can be expanded to form the bag into rectangular shape. Means are provided for flattening the ends of the open bags so as to form a square bag end. If desired, the bags may be heat sealed in square form to prevent any chance of their returning to their folded state. The bags of the type normally used include a pair of side wall panels which are connected along their contiguous edges by a pair of inwardly folded gusset panels. By applying a spot of adhesive between each pair of bags in a series, a pull upon the leading edge of the side panel of the foremost bag wiil tend to pull the flat sides of the bag apart, folding the gusset panels toward a common plane. As the opposite side wall is connected to the forward panel of the next bag, when the foremost bag is opened, a further pull will tend to open the second bag, and so on throughout the length of the chain of bags. The bags are supplied in this manner and connected in as long chains as is practical. In placing the bags into the hopper of the bag opening mechanism, a spot of adhesive may be applied between the last bag of one chain and the forward bag of the next so that the bag opening apparatus will operate continuously.

A feature of the present invention resides in the method of placing the bags upon spaced mandrels while the mandrels are collapsed so that the bags are elongated beyond their normal width by the connecting spots of adhesive. However, when the mandrels are expanded, the adhesive connection is broken, and from this point onward the bags are individual bags and operate as such.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claims:

ice

In the drawings forming a part of the specification;

FIGURE 1 is a diagrammatic side elevational view of an apparatus for erecting bags.

FIGURE 2 is a side elevational view of a series of bags in slightly expanded relation.

FIGURE 3 is a bottom panel view of a series of bags in more greatly expanded form.

FIGURE 4 is a perspective view showing the position of a single bag upon an expandable and contractable mandrel.

FIGURE 5 is a view similar to FIGURE 4 showing the mandrel in expanded position.

FIGURE 6 is an end elevational view of a contracted mandrel showing the guides for expanding the mandrel.

FIGURE 7 is a view similar to FIGURE 6 showing the mandrel in expanded form.

FIGURE 8 is a sectional view of the guide used for contracting the mandrels, the position of the section being indicated by the line SS of FIGURE 1.

FIGURE 9 is a diagrammatic view of the guide for expanding the mandrels.

FIGURE 10 is a diagrammatic collapsing the mandrels.

In the present invention, the apparatus is shown diagrammatically rather than in detail, as it is believed that a better understanding of the invention may be obtained from the diagrammatic views. It is felt that the showing is sufficiently clear to permit one skilled in the art to produce the apparatus, and this has been indicated by the fact that the prototype was constructed from similar sketches.

An important feature of the invention resides in expanding the bags 10 while the bags are connectedlightly by spots of adhesive indicated at 11. In general, the bags may be of any suitable type which can fold to form a square end, the bags in question including a generally rectangular side wall 12., a pair of side wall panels 13 which overlap to form a single rectangular side wall similar in size to the wall 12, and rectangular gusset panels 14 of similar size connecting the free edges of the side walls i2 and 13. The ends of the tube thus formed is folded upon itself to form a seam 15 which closes the end of the bag. As a result, the side walls 12 and 13 are normally in fiat contiguous relation with the two gusset flaps 14 folded between the sides of the panels 12 and 13. However, when squared up, portions of the gusset panels fold along diagonal fold lines to form a square bottom as is well known in the art.

The flat bags are thus provided in stacks, each bag being connected to the next bag by a small spot of adhesive 11 which may be severe-d or which will break before the material forming the bag will tear. When each series of connected bags is placed in the feeding hopper 15 of the apparatus shown in FIGURE 1, a spot of adhesive is applied between the end bags of the adjoining surfaces so as to provide a continuous chain of bags. The apparatus includes an elongated conveyor supported by a pair of parallel shafts 17 and 19 which support sprockets or pulleys 20 and 21 respectively supporting a pair of parallel chains or belts 22. The chains 22 support a series of expandable and contractible mandrels 23 which are of assistance in opening the bags 10.

As is diagrammatically illustrated in FIGURES 4-8, the mandrels 23 include a pair of side plates 24 pivotally connected at 25 to a cross member 26 secured in any suitable way to the chains or belts 22. The plates 24 are movable from an upwardly and inwardly converging relation as shown in FIGURES 4 and 6 to parallel relation as indicated in FIGURES 5 and 7. The side plates 24 are inserted into the bags 10 while in planes substantially normal to the planes of the bag sides. In other words, these plates 24 are substantially the width of the view of the means of connected gusset panels of the bag, and are arranged to fold the gusset panels outwardly into a common plane throughout the depth of the bag.

The mandrels 23 ride over a guide plate 27 having side flanges 29 which are spaced apart a distance sufficient to permit the side plates 24 to converge inwardly in the manner shown in FIGURE 6 at the inlet end 30 of the guide track which is adjacent the hopper 16. As indicated in FIGURE 9, these flanges 29 converge together to midpoint 31 at which point the flanges are sufficiently close to have swung the plates 24 into parallel relation. When in this position, the walls of the bag are squared up into generally rectangular form.

As indicated in FIGURE 1 of the drawings, a pair of V endless belts 32 which are traveling at approximately the same speed as the bags on the conveyor engage the gusset flaps 14 of the bag and press them against the mandrel plates 24. As illustrated in this figure, the endless belts 32 are arranged at an angle to the horizontal path of the mandrels and therefore frictionally engage the bags and draw them downwardly over the mandrel structure. Thus while the bags are only partially down on the mandrels at the start of the operation, they are pulled downwardly to the full depth of the bag by the endless belts 32 arranged on both sides of the conveyor belts or chains 22.

The mandrels 23 are provided with a collapsible end designed to form a platform against which the ends of the bags may be pressed. While this arrangement is usually of the positive functioning type such as a pair of toggle plates, in the simple arrangement illustrated, the end platform forming member 34 is hingedly connected at 35 to the upper end of one of the plates 24, the plate 34 together with the side plates 24 forming a rectangular mandrel which substantially fills the bag 10. A bearing 36 which may include a spring supports a plunger 37 having an upper end 39 which bears against the plate 34 and a lower end 40 which may slide along the surface of the guide plate 27, and over a cam rail 41 near the end of the upper reach of the conveyor. In any event, as each mandrel nears the end of the upper reach of the conveyor and when the bags have been pulled downwardly on the mandrels, the end plate 34 forms a platform or table against which the bottom of the bag may be pressed. A pressing or sealing belt 43 is supported by suitable pulleys 44 mounted on parallel shafts 45 parallel to the shafts 17 and 19 supporting the conveyor 22. If the bags are of heat sealable material, the belt 43 may Y comprise a heated belt which presses the bag end against 'in their expanded form as the mandrels travel about the sprockets 2i) and then diverge outwardly toward the outlet end of the guide plate as indicated at 50. The outward divergence of the flanges 47 permit the side plates 24 of the mandrels 23 to collapse to the relation illustrated in FIGURE 8 and to insure the collapse of the mandrels, inner guide flanges 51 which also diverge and which are parallel to the diverging flanges 47 swing the mandrels toward their collapsed position.

' A means is provided for removing the bags from the mandrels and conveying them to a filling mechanism or the like. In the arrangement illustrated, this structure comprises a perforated belt 52 supported by a pair of sup- I porting pulleys 32 mounted on parallel shafts 54 and located beneath the conveyors 22 and the mandrels carried thereby. A suction box 55 having an open top or having a perforated top lies beneath the upper reach of the belt 52,

and the bags 10 are drawn by this partial vacuum on to the belt 52. The belt 52 is arranged in divering relation'to the conveyor belts 22 so that upon movement of the belt 52 in timed relation with the conveyor chains 22, the bags 10 are withdrawn from the mandrels 23 and are conveyed to a suitable destination. Due to the flat squ-are ends on the bags, they are quite stable during this conveying operation.

In the operation of the apparatus, the bags are placed in a suitable hopper, and in the arrangement illustrated are supported with their open ends downwardly and in a generally vertical position. The foremost bag of the series is placed over the upper end of one of the mandrels, and the movement of the conveyor chains 22 acts to draw the bags one at a time over the spaced mandrels, the movement of the bags being restricted by suitable means at the end of the hopper so as to release the bags one at a time, and to open the bags to a certain extent before they are completely released. After a predetermined period of travel during which the bags .move farther down on the mandrels, the mandrels are expanded by the flanges 29 of the guide plate 27, the mandrel plates 24 folding the gusset planes 14 into a common plane and swinging the bag sides 12 and 13 into parallel relation. This action causes the adhesive bond 11 between adjoining bags to break. Furt-her travel of the mandrel brings the endless friction'belts 32 against the sides of the bag, and the downward inclination of the belts 32 causes the bag to be pulled down over the mandrels. At about this time the end plates 34 are swung up into right angular relation to the sides 24 and the ends of the bag are sealed or flattened by the belt 43 which travels at the same speed as the conveyor chains 22.

The mandrels are maintained in expanded condition until the bags are inverted at which time the mandrels are collapsed by the guide flanges 51 and the bags are drawn on to the perforated belt 50 by action of the suction box 55. The squared up open bags are then delivered to a suitable conveyor and to a desired destination.

In accordance with the patent statutes, I have described the principles of construction and operation of my improvement in method and apparatus for expanding bags, and while I have endeavored to set forth the best embodiment thereof, I desire to have it understood that changes may be made within the scope of the following claims without departing from the spirit of my invention.

I claim:

1. A bag opening apparatus for use in combination with a series of contiguous bags arranged in flat face contact, the bags having a closed end and an open end, and the bags being connected in a chain by separable spots of adhesive between the sides of the bags near the open end thereof, the apparatus including a hopper for supporting said bags in face contact,

a series of mandrels engage able into the open ends of said bags to hold the bags open,

means supporting said mandrels in spaced relation for movement about an endless path,

means for moving said mandrels about said path while engaged in at least one bag acting to successively open said bags in said chain, and

means guiding the bags of said chain successively on to said mandrels as they are drawn from said hopper.

2. The structure of claim 1 and including means for separating the adhesive connection between said bags as they are carried by said mandrels.

3. The structure of claim 2 and including means for removing said separated bags from said mandrels. V 4. A bag opening apparatus'for use with bags each havmg a pair of side panels having parallel side edges connected by pairs of gusset panels and having an end seam forming a closed bag with: opposite ends of said panels being open, the bags being foldable from flat form in which the gusset panels are sandwiched between the side panels to a rectangular expanded form, the side panels of Id 23 the adjoining bags being connected intermediate their side edges and adjoining their open ends by spots of adhesive to provide a chain or" bags, the apparatus including,

a hopper for supporting the chain of bag an endless conveyor supporting a series of equally spaced aligned mandrels thereupon, the spacing between the centers of said mandrels being somewhat greater than the combined width of said gusset panels on each of said side panels, said mandrels being collapsible toward one another in a direction transversely of the direction of travel of said mandrels, whereby said bags may be elongated in the direction of travel thereof as the bags are applied over said mandrels while connected in a chain, and

means for expanding said mandrels to fold said bag panels into rectangular expanded form, thereby pulling the adhesive connection between said bags apart and squaring up the individual bags. 5. The structure of claim 4 and including means for drawing the bags over the mandrels to substantially the full depth of the bag.

6. The structure of claim 4 and including means for folding the bag ends into fiat form over the mandrel ends.

7. The structure of claim 4 and including a pair of inclined conveyor belts engaging the bags on the mandrels and drawing them over the mandrels to substantially the full depth of the bags.

8. A bag opening apparatus for use with bags each having a pair of side panels having parallel side edges connected by pairs of gusset panels and having an end seam forming a closed bag end, the opposite end of said panels being open, the bags being foldable from flat form in which the gusset panels are sandwiched between the side panels to a rectangular expanded form, the side panels of the adjoining bags being connected intermediate their side edges and adjoining their open ends by spots of adhesive to provide a chain of bags, the apparatus including,

a hopper for supporting the chain of bags, an endless conveyor supporting a series of equally spaced aligned mandrels thereupon, the spacing between the centers of said mandrels being somewhat greater than the combined width of said gusset panels on each side of said side panels, said mandrels each including a pair of plates pivotally supported upon said conveyor on pivots parallel to the direction of travel of the conveyor and movable from a position in which the ends of the plate most remote from the conveyor converge together to a parallel position, said plates when in parallel position being spaced apart a distance substantially equal to the width of the side walls and said plates being of a width substantially equal to the combined width of said gusset panels,

said hopper being so located relative to said conveyor to permit the bags to be drawn one by one on to the mandrels while the plates are in converging position, said bags being elongated in the direction of travel of the mandrels beyond the width of the plates while still in a continuous chain, and

means for successively swinging said plates into said parallel position as the mandrels travel with said conveyor to fold the bags successively into rectangular expanded form.

9. The structure of claim 8 and including means engaging the portions of said bags which are in face contact with said plates to draw the bags farther on to said mandrels.

10. The structure of claim 8 and in which the mandrels include an end forming member forming an end wall between said ends of said plates when the plates are in parallel relation, and

means engageable with the closed ends of the bags carried by said mandrels for flattening the bag ends against said end forming members.

11. A bag opening apparatus for use with bags each having a pair of side panels having parallel side edges connected by pairs of gusset panels and having an end seam formin a closed bag end, the opposite ends of said panels being open, the bags being foldable from flat form in which the gusset panels are sandwiched between the side panels to a rectangular expanded form, the side panels of the adjoining bags being connected intermediate their side edges and adjoining their open ends by spots of adhesive to provide a chain of bags, the apparatus including,

an endless conveyor supported by a pair of parallel horizontal axes and having an upper reach and a lower reach,

a series of spaced mandrels mounted in spaced relation on said conveyor and collapsible transversely of the conveyor,

said mandrels in expanded form being of a size substantially equal to the inner dimensions of the individual bags,

a hopper at one end of said conveyor supporting said bags with the open ends thereof directed downwardly toward the upper reach of the conveyor, and including means guiding the open bags over the successive mandrels when connected as a chain,

me ans maintaining the mandrels in collapsed form while the bags are at least partially inserted thereover,

means successively expanding said mandrels while the bags are supported thereby to fold them into rectangular form, and holding said bags expanded as the mandrels travel about the axis at the end of the upper reach of the conveyor, moving the bags into upright position,

conveying means beneath the lower reach of the conveyor to convey the expanded bags, and means collapsing said mandrels as they pass over said conveying means to release the bags therefrom.

12. The structure of claim 11 and including means engageable with the bags on the expanded mandrels for insuring the insertion of the mandrels into the bags to the full depth of the bags.

13. The structure of claim 12 and including means engageable with the closed ends of the bags While on said expanded mandrels to flatten the bag ends into a plane generally normal to the planes of the remainder of the bag panels.

References Cited by the Examiner UNITED STATES PATENTS 515,121 2/1894 Hunt 9335 1,368,633 2/1921 Johnson 93-35 2,437,117 3/ 1948 Orstrom 53384 2,601,480 6/1952 Williams 53-384 2,653,751 9/1953 Vogt 22953 2,671,602 3/1954 Vogt 22-953 FRANK E. BAILEY, Primary Examiner.

Claims (1)

1. A BAG OPENING APPARATUS FOR USE IN COMBINATION WITH A SERIES OF CONTIGUOUS BAGS ARRANGED IN FLAT FACE CONTACT, THE BAGS HAVING A CLOSED END AND AN OPEN END, AND THE BAGS BEING CONNECTED IN A CHAIN BY SEPARABLE SPOTS OF ADHESIVE BETWEEN THE SIDES OF THE BAGS NEAR THE OPEN END THEREOF, THE APPARATUS INCLUDING A HOPPER FOR SUPPORTING SAID BAGS IN FACE CONTACT, A SERIES OF MANDRELS ENGAGEABLE INTO THE OPEN ENDS OF SAID BAGS TO HOLD THE BAGS OPEN, MEANS SUPPORTING SAID MANDRELS IN SPACED RELATION FOR MOVEMENT ABOUT AN ENDLESS PATH, MEANS FOR MOVING SAID MANDRELS ABOUT SAID PATH WHILE ENGAGED IN AT LEAST ONE BAG ACTING TO SUCCESSIVELY OPEN SAID BAGS IN SAID CHAIN, AND MEANS GUIDING THE BAGS OF SAID CHAIN SUCCESSIVELY ON TO SAID MANDRELS AS THEY ARE DRAWN FROM SAID HOPPER.

Images