Roll forming carton lidding machine

Abstract

A machine for emplacing and forming lids on filled cartons is comprised of a lid supply means and a carton receiving station. Means are provided for feeding the lids to a position above the carton receiving station where the open top of the carton is mated with the lid which is formed by pressure rollers to conform to the carton walls. The lids have flaps and corner tabs which are folded downward and inward and adhered to the flaps which engage the carton walls, all of the folding is done in sequence but simultaneous steps. Novel means are provided for adapting the machine to various lid sizes thus reducing the inventory of blank lids that must be stocked for various carton sizes.

Description

BACKGROUND OF THE INVENTION

In describing the apparatus and method herein to be disclosed reference shall be made to the packing of paper, specifically ream packages of cut size paper in cartons. It should be understood, however, that the uses of the method and apparatus are not so limited and that reference to the particular use is for convenience, since the packing of cut size paper graphically illustrates the needs and the gratification of the needs effected by the disclosed subject matter.

As is well known, cut size packages of paper, usually 500 sheets wrapped in a paper wrapper, are difficult to handle for transport and sale because the packages are bulky, heavy and, in a sense fragile. Thus, the industry has adopted the practice of packing the cut size packages in a carton usually containing 5,000 sheets divided into 10 equal packages or reams of 500 sheets each. The outer carton is usually fabricated from corrugated paperboard having sufficient strength to encompass and confine the plurality of packages while protecting same against impact or shock that would render the wrapped sheets unusable because of wrinkles, tears, curled edges, and bent corners and the like. Because of the necessity for strength and impact resistance, the board from which the cartons are fabricated must be of substantial thickness and weight, thus making the carton and contents quite heavy to further increase storage bulk and shipping costs en route from manufacturer to consumer.

More recently, it has been realized that if the cartons in which the ream wraps or packages are packed tightly enough within the carton and the carton embraces and encloses the packages into a rigid unit, the container and its contents become, as it were, an integrated unit capable of self-support and in turn, capable of supporting other loads, as for example, containers stacked one on top of the other as in palletizing, warehousing, etc. It is also quite possible to reduce the bulk and weight of the material from which the cartons are fabricated since the contents share in the load-supporting function.

The knowledge that integration of container and contents produces favorable results has led to a rash of developments in methods of packing, container formation and loading, lid attachment, etc., and the necessary and preferably automated, equipment to effectuate the desired results.

THE PRIOR ART

One of the earliest ventures along the lines of packing and integrating containers and load as a unitary assembly to resist damage by crushing, bending, impacts and the like is disclosed in Ziliox U.S. Pat. No. 3,120,727 issued Feb. 11, 1964 and the companion apparatus U.S. Pat. No. 3,002,326 issued to Ziliox and Carter on Oct. 3, 1961. In this system, the carton is actually formed about the contents in an inverted position, the lids being adhered to the carton bottoms or trays after which the cartons are overturned and palletized right side up.

Other alternative and more recent developments are shown in recently issued U.S. Pat. No. 3,634,995 assigned to International Paper Co. and in the prior art cited during the prosecution thereof, and other prior art as reflected in U.S. Pat. Nos. 3,162,100; 3,449,183; 3,038,284; 3,501,895; 3,516,227; 2,850,858; 3,145,518; 2,848,856; 3,688,466; and 3,126,685, all of which patents have been considered and which disclose systems and apparatus which differ in several material aspects from the method and apparatus to be subsequently disclosed.

Inspection of the prior art discloses that the more recent approach to the packing of contents in containers comprises the loading of preformed carton bottoms as trays with the contents as tightly as possible and thereafter pressing a pre-scored, pre-cut lid blank having side and end flaps and infolded adhesively secured tops onto the contents while forming and adhesively adhering the end tabs to secure the side and end walls of the lid in extremely tight immobile position over the open end or face or side of the filled carton. Such is the procedure followed in U.S. Pat. No. 3,634,995. Such is the procedure with which the present disclosure and claims deal, albeit the manipulative steps in effecting the folding are substantially different, as will subsequently become apparent.

The prior art methods and apparatus are, in fact, consummated in the apparatus shown in U.S. Pat. No. 3,634,995, and essentially comprise a folding operation wherein the closure blank, be it lid or simply a flexible wrapper, is positioned over and wrapped or folded about the previously filled container. The apparatus for filling, irrespective of the product, is conventional and essentially forms no part of the inventive subject matter.

The closure blank is fed into place over the filled container. The filled container is then elevated into what the art terms a "well" which folds the closure around the sides of the container and, in some cases, adheres the folded sides of the closure to the container.

A "well," as shown in the art usually consists of a stationary member or members defining a periphery of an open hole into which the container is lifted. The stationary members contact the edges of the blank and, as the container moves upward, the relative movement past the stationary members causes folding of the marginal edges of the blank down along the container walls, which walls are generally vertical and parallel to the longitudinal axis of movement of the container. Since an extremely tight fit of the closure to the container is necessary, the edges or stationary members defining the mouth of the well are positioned and spaced so as to very closely, within 3/8 inch or less, approximate the dimensions of the outer dimensions of the side walls of the container. In all cases, the folding pressure required to bend the marginal surfaces of the closure down into assembled position is all concentrated at the area of the lid immediately adjacent to the fold line about which the marginal areas of the blank bend. As the fold is completed as the container moves up in the well, the pressure exerted on the downfold edges decreases to an almost uniform pressure. However, because of the initial folding pressure the cover may be distorted with the result that the cover does not adhere tenaciously to the bottom or tray with the result that the cover may move and thus destroy the sought for integrated action of the contents and the closed container.

Similarly, because of the use of fixed members considerable machine adjustment is involved in switching from one carton size to another.

THE INVENTION

The present invention, then, has for a general objective the provision of a relatively inexpensive efficient and extremely versatile carton lidding machine.

A particular object of the invention is to provide a carton lidding machine capable of producing tightly lidded cartons which are integrated with the contents to provide improved impact resistance to the package and contents.

Another object of the invention is to provide a lidding machine which can be installed easily in any carton packing line.

Still, a further object of the invention is to provide a lidding machine which is readily adjustable to accommodate different sizes of cartons.

Another object of the invention is to provide a carton lidding machine devoid of complicated feeding mechanisms.

These and other objects of the invention not specifically alluded to in particular, but, none-the-less, inherent therein and readily apparent to those skilled in the art, may be accomplished by the apparatus described hereinafter in conjunction with the drawings, wherein:

FIG. 1 is an end, top and right-side perspective view of the complete carton lidding machine,

FIG. 2 is a top and left-side broken away perspective view showing details of the lid feeding arrangement,

FIG. 3 is a partial perspective view showing the initial step in the lid feeding operation,

FIG. 4 is a view, similar to FIG. 3, but showing the lid in its carton engaging position,

FIG. 5 is a top and left side, partial perspective view showing the mating of the carton and lid at the lid placement station and the flap folding mechanisms,

FIG. 6 is a partial perspective view showing the first step in the flap folding operation,

FIG. 7 is a view similar to FIG. 6 showing an intermediate stage in the flap folding sequence,

FIG. 8 is a perspective view similar to FIG. 5 showing the final closure position of the closing elements,

FIG. 9 is a perspective, partial view of the lid as finally closed on the carton body,

FIG. 10 is a partial view of the lid flap folding rollers in null position to illustrate the manner of effecting sequential folding of the side and end flaps,

FIG. 11 is a partial, schematic view of the means for mounting the lid feeding means and flap folding means for rapid adjustment to accommodate various sized cartons and lids,

FIGS. 12a, 12b and 12c are views showing, in ladder schematic, the control means for the functioning elements of the apparatus, and

FIG. 13 is an inverted, perspective view of one lid feeding finger.

Turning now to FIG. 1, the overall apparatus is shown in assembled form. As clearly illustrated, the machine is assembled on a frame 10, fabricated from conventional structural angle iron, channels and the like, and is comprised of four vertical legs, only three legs being visible, 1, 3, 5, and a pair of main rails 9 and 11. The frame 10 is essentially divided into two areas 20 and 30; the area 20 being the lid supply area and the area 30 being the lid applying area.

As shown, the lid supply area embraces an elevator platform 13 upon which, in horizontal position is stacked a supply of lid blanks 15. As the lid blanks 15 are fed individually from the top of the stack by the lid feeding means, to be described hereafter, the elevator platform 13 is raised incrementally by means of a plurality of lift chains 17 and 19 which are trained over drive sprockets 21 and 23. Sprockets 21 and 23 are in turn driven through a magnetic clutch 25. Clutch 25 is driven from a cross shaft and electric motor, not shown, so that the motor operates continuously but the sprockets 21, 23 operate intermittently to take up on chains 17 and 19 as lid blanks 15 are fed from the elevator platform. It should be noted that the motor and drive setup, including clutch 25 are all conventional and a part of a conventional arrangement. It should also be realized that two elevator chain and drive sprocket arrangements are provided adjacent main rail 11, but these items are not completely visible in the view of FIG. 1 though it should be apparent that cross shafts 27, 29 coordinate the rotary movement of all four such elevator sprockets 21, 21' and 23.

Disposed directly in line with the elevator platform 13 is the lid feed mechanism 130 which will be described in greater detail in connection with FIG. 2. It suffices to say that the mechanism is operated by a free piston, double-acting hydraulic actuator 31 which is mounted on cross frame members 35 and 37. The piston is connected to the sheet feed assembly 130 by means of a cable which is trained over pulleys 42, 44, suitably mounted on the main frame, so that as the jack piston moves to and fro in the barrel, the assembly is also moved back and forth via the cable 38. The feed assembly 130 is mounted upon and guided by a plurality of parallel and horizontally disposed slide rods 39 and 41.

Also disposed above the lid feeding area 20 and suitably supported on main frame 10 is a hot melt adhesive reservoir and heater apparatus 40 having adhesive discharge hoses 43 and 45 leading to applicator nozzles 47 and 49 also suitably mounted on main frame 10 in a position to be described fully in connection with FIG. 3.

As is further shown in FIG. 1, the carton stack of lid blanks 15 on elevator platform 13 is in contact with a stack guiding means 51 and 51' (only one being shown in FIG. 1) which will also be described with reference to FIGS. 2 and 3.

As seen in some detail in FIG. 1, the lidding area 30 of frame 10 is provided with the instrumentalities necessary to effect the lidding operation. Disposed at the bottom of the frame 10 in area 30, is a roller conveyor comprised of a vertically movable frame 57 having a plurality of conveyor rollers 59 journalled therein. The axes of the rollers are disposed parallel to each other and also to the direction of movement of lids 15 from the lid supply area 20 to the lid applying area 31. As will be further described with respect to FIG. 4, the rollers 59 may be power driven via a chain and sprocket drive 67 from a motor, not shown, carried beneath frame 57. The whole assembly, motor, chain and sprocket drive, etc. is purely a conventional arrangement in the art and hence need not be described in further detail. Also journalled in frame 10 between vertical leg 3 and vertical hanger 69 and as well on an adjunctive conveyor frame 65 are a plurality of idler rollers 61 which convey cartons to and away from the lidding station 30.

Frame 57 is supported upon and by a hydraulic jack or motor 60. The mode of connecting motor 60 to the frame is purely a matter of mechanical skill and design. It suffices simply to say that as jack 60 is actuated the entire frame 57 and, of course, rollers 59 are lifted vertically toward the top of the main machine frame 10. Suitable valving means is provided to control the jack and reference will be made thereto in connection with FIG. 12.

As is further shown in FIG. 1, the upper portion of the main frame 10 in the lid applying area 130 is occupied by the lid positioning and flap folding mechanism 50, the details of which are more readily apparent from consideration of FIGS. 2 to 5. Before describing the mechanism, previously noted, in detail, however, attention is directed to the lids which are pre-cut and pre-scored in such a manner as to accomplish the desired results in conjunction with the machine operation.

As clearly shown in FIG. 2, each lid comprises a central cover area 71 bounded by score lines 72 and 73 which define the length and width dimensions of the cover area. The marginal edges of the lids beyond the score lines define side and end flaps 77 and 75 respectively which are subsequently folded down and into engagement with the side and end walls of the carton receptacle or bottom tray containing the products.

At each corner, the side flaps 77 are provided with cutouts which extend from the marginal edges of the lid inwardly toward score lines 72 and are aligned with score lines 73. Thus the corner areas of the end flaps 75 define tabs 101, 102, 103 and 104 which can be and are folded downwardly and inwardly and thus tucked in behind the side flaps during the cover folding and applying sequence.

Turning attention again to FIG. 2, it will be seen that the lid feeding assembly 130 includes a cross-slide bar 81 mounted on the slide rods 39 and 41 previously noted. Projecting forwardly, i.e., toward the lid stack, from the cross slide bar 81 are a pair of stack stripping and blank feeder tongues 83, 85 which engage the topmost blank of the stack of blanks and pushes this blank toward the lidding station as the cable 38 is actuated by the hydraulic motor 31. As the blank moves from the stack its edges and sides are contacted by a pair of horizontal and parallel guide rails 87 and 89 and a pair of edge guides 91, 93 which align the blank and guide it in proper position toward the lidding station. Preferably the trailing edges of the side guides 91 and 93 are provided with some form of retarding means such as a pad or brush to frictionally engage the edges of the blank. This assures that the blank is positively engaged by the feeder tongues 83, 85 as it leaves the supply stack. Also, the retarding means assures that only a single blank is fed from the stack since the frictional forces acting on the edges of the topmost blank are greater than the frictional forces acting between the bottom surface of that blank and the top surface of the next succeeding blank.

As the blank is fed forward it contacts a control switch, to be described in connection with FIG. 12, which causes a discharge of adhesive from the nozzles 47 and 49. As clearly shown in FIG. 6, the adhesive is applied to very limited areas 95 and 97 of the leading corner tabs 101 and 102. Subsequently, as the lid blank travels further the leading edge contacts a second control switch which again activates the adhesive system to deposit a similar adhesive pattern on the trailing corner tabs 103, 104.

Particular attention is directed, now, to the configuration of the feeder tongues 83 and 85 with reference being made to FIG. 13 showing one of these instrumentalities in an inverted, perspective view. As is clearly apparent the lid blank contacting end of the tongue is curved so that the area 105 moves easily across the stack of blanks even though the height of the stack or the lid thickness may vary somewhat. The sheet feeder tongues 83 and 85 contain several innovative features. Each is individually spring loaded permitting a limited amount of vertical travel. As the stack of lid blanks rises, the edge of the topmost blank contacts the section of face 109 ahead of the pin 111. Through conventional control means, the stack rises until both tongues 83 and 85 have their respective surfaces 109 in contact with the topmost blank. Thus, the figures are self aligning and a positive feed is assured even though the blanks may not be uniformly horizontal.

A further feature of the tongues 83 and 85 is the construction beneath the barb or pin 111. Beginning at the base of the barb, the tongue is bevelled away through 110 into plane 105. Thus, as feeding begins, no part of cross land 107 can come into contact with any lid blank other than the one being fed. This reduces the possibility of double feeding. The surface 105 is interrupted by a step defined by a cross land 107, a terminal end surface 109 and an intermediate beveled surface 110 defined between surface portion 105 and the land or riser 107. Affixed centrally of the land 107 is a barb or pointed projection 111 disposed along and alinged with the central axis of the land or riser surface. The barb 111 is designed to enter into the fluted area formed between the solid surfaces of the lid blanks which are formed of the usual corrugated board. The barbs enter into the fluted area and the lands or risers engage the edge of the blank to provide a measure of positive control over the blanks as they are moved between the alignment guides 91 and 93 and traverse the support rails 87, 89 to the final lid forming position overlying the conveyor at the lid forming station 30.

At this point it should be noted that since elevator platform 13 is freely suspended from the lift chains 17 and 19 it is free to move in all directions in a general horizontal plane. In order to align the elevator platform and also the lid blank stack with the feeding mechanism there are provided a plurality of guide angles 51,51' and a second set of guide channels 113, 113'. All four guides are mounted in parallel vertical relation so as to engage the corners of the lid blanks to guide same vertically so that the uppermost blank 15 in said stack will be properly aligned for sliding removal via the feed mechanism previously described.

Considering now the lid forming mechanisms and operation it will be noted that a previously filled carton tray 120 enters the lidding area 30 via roller conveyor 61. In order to stop movement of the tray in the proper position on the lifting conveyor rolls 59, there is provided a vertically movable stop roller 121 mounted in slide brackets 122 on vertically slidable trunnions 123 mounted on lift conveyor frame 57. These trunnions 123 are in turn operated from a retracted to a raised position by means of an air cylinder or hydraulic motor, not shown, suitably connected thereto as is readily apparent to the skilled mechanic. A similar lift roll trunnion assembly 124, 126, 128 is provided on conveyor frame 63 upstream of the lidding station 30. The operation of the roll lifting means is under the control of one of a pair of electric eye light sources and light responsive cells 125 and 127 with directional reflectors 129, 131 disposed directly opposite all of which are positioned on cross members 133 of the main frame and cross member 135 which is, in turn, attached to frame 57. As is conventional, an article moving through the area interrupts the light beam from sources 125 and 127 and this happenstance can be used to generate a control signal. As will be more fully described in connection with FIG. 12, the movement of the carton tray 120 between source 125 and reflector 129 generates a signal which controls the movement of the stop rolls 121 and 124 into raised position to stop the tray in the lidding station, and to prevent entry of a succeeding carton into the lidding area 130 until the lidding operation has been completed. Preferably, the carton is centered along the conveyor axis by friction guides, not shown, but well known in the art, which are positioned on conveyor frame 63 at some point upstream of the lidding station.

Disposed immediately above the vertically movable conveyor assembly comprised of frame 57 and rolls 59 is a rectangular presser plate 140. This plate is suspended by a vertical shaft 141 from cross member 143 rigidly mounted on main frame 10. The upper end of shaft 141 may be connected to some form of thrust resistant mechanism 145 such as an air or hydraulic accumulator whereby the force necessary to move the presser plate upwardly may be regulated as conditions may warrant.

As shown in FIG. 5, the presser plate is, in its at rest or null position, lowered so as to be suspended immediately above, but out of contact with the flat, lid blank 15 which is resting on the supporting slide rails 87, 89 in its final position overlying the filled carton bottom 120.

Disposed above the presser plate 140 and pivoted on suitable brackets 147 attached by any suitable technique to the main frame 10 or cross member 143 respectively are a plurality of lid forming rolls grouped in four pairs 149, 149', 151, 151', 153, 153' and 155, 155'. The forming rollers are mounted on axles carried by pairs of hangers, all identical and identified, as a group, by numeral 157 which are in turn carried on pivot shafts 161, 161', 163, 163', 164, 164', and 165, 165'. Each pivot shaft, in turn, carries a spring armed lever 167, 168, 169, and 171, 171' non-rotatably attached thereto. The ends of these levers overlie the top of the presser plate 140 and are provided with contact pads, generally noted by numeral 175.

The pads carried by spring lever arms 167, and 169' are located in their rest position, closer to the presser plate 140 than are those carried by lever arms 168' and 171. This permits the end flaps 75 to close slightly ahead of the side flaps 77. To adjust the stop position of lever arms 168', 171' at their lowered position a suitable stop cam or similar means 177 may be provided on hanger arms 157 to abut against the stationary members 147; this again being an arrangement within the skill of the ordinary, competent mechanic which need not be described in minute detail herein.

It is particularly important to note in FIGS. 4 to 7, inclusive, the provision and location of the tab folding fingers 191, 193, 195, 197. As will be described in connection with FIG. 10, these fingers are adjustably positioned on the main frame 10 and project inwardly to overlie the lid blank support rails 87 and 89 so that they may engage the end tabs 101, 102, 103 and 104 when the blank is in the process of being first engaged and folded on the open topped carton receptacle or tray 120 as will be presently apparent.

Prior to proceeding into a discussion of the operation of the machine and the novel folding method it performs, attention is directed to FIG. 11 which is a partial schematic view through the middle of the machine shown in FIG. 1. For clarity, some parts of the apparatus have been deleted in this view.

The side rail of main frame 10 is shown with respect to its midpoint and the distances from this midpoint to the center line of each of the blank stacking area 20 and the lid folding area 30 designated by arrows and the identification A and B. The A and B distances must remain constant. However, since it is contemplated that more than one size of carton may be used, some arrangement must be provided to adjust the position of blank guides 113' and 51' relative to the center line, this latter distance being identified by the letters C, D. Similarly, an equal dimensional adjustment must be made between the flap folding rollers 151, 151' and 155, 155', this distance being identified as distances E, F. In order to accomplish this adjustment the side rails of the main frame 10 are provided with slide blocks, as for example 201, 205 in FIG. 11, which blocks slidably support a pair of parallel rack bars 207, 209 which extend parallel to the side rails for the full length of the main frame. The ends of these bars adjacent the lid supply area are provided with complimentary and facing gear teeth which mesh with a common pinion 212 disposed intermediate the bars and in engagement with both. Thus, as pinion 212 is rotated an equal or opposite longitudinal motion is imparted to each rack bar 207 and 209.

Fixed to the rack bars 207 and 209 are hanger blocks 211, 213, 215 and 217. The blocks 211 and 215 are pin connected to the upper rack bar 207 and slide freely with respect to bar 209, while the blocks 213 and 217 are pin connected to the rack bar 209 and slide freely with respect to bar 207. Thus as the bars are moved longitudinally in opposite directions the hanger blocks 211 and 213 move toward or away from each other an equal distance depending on the direction of motion of the rock bars 207, 209. Similarly, the blocks 215, 217 move in the identical fashion toward and away from each other as the rock bars are moved by rotation of pinion 212 in the chosen direction.

Affixed to and movable with the hanger blocks 211, 213, 215 and 217 are a plurality of cross member structural supports 221, 223, 225 and 227. These members support the vertical stack guides 113' and 51' and the flap folding rollers 155, 151, etc., as well as the end top folding fingers 191, 193 as visible in FIG. 11. The glue applicators are also supported on a movable cross member.

The entire blank feeding means moves with hanger block 211 such that the blank feeder tongues 83, 85 remain in the same horizontal disposition relative to the edge of the stack of blanks.

Further, the glue applicators move in conjunction with hanger block 213 such that no further adjustment is required. Thus, a complete change of size in the short direction is accomplished by rotating pinion 212 to a predetermined position.

Thus as is apparent, the movement of the rack bars varies the dimensions C, D and E, F equally so that both may accommodate lids of different dimensions selected for carton receptacles of different dimensions. Fortunately, carton sizes of the type adapted for the particular use described are fairly well standardized as to length, i.e., the carton dimension which parallels carton movement in FIG. 2. These cartons are dimensioned, for the most part, to receive two reams of wrapped paper sheets side-by-side of 81/2 .times. 11 inches up to 81/2 .times. 14 inches. Thus the length of the cartons is almost universally 17 inches by 11 plus a fraction up to 17 inches by 14 inches plus a fraction depending on ream size, i.e., sheet dimensions, since the sheet count is standardized at 500 sheets per ream.

There are, however, instances particularly when the cut sheets are to be used in standardized equipment, such as computer readout stations and governmental use where the sheet width must be 8 inches instead of 81/2 inches. Thus, the carton length, i.e., the dimension in its direction of movement into the lidding area will become 16 inches rather than 17 inches. To accommodate this variation and, regardless of length, to assure proper positioning of the carton in the lidding area, the stop means, which consists of the roller 121 previously described, is so arranged that one of two sizes of roller 121 may be readily inserted and removed selectively in the trunnions 123. One roller is 1 inch in diameter, the other 2 inches in diameter. Thus, by a simple substitution of one roller for the other the stopped position of the carton bottom 120 can be readily adjusted to position it directly beneath the presser plate 140 regardless of its dimension. It should be recognized of course that the unique operation of the sealing roller assembly can readily accommodate the variation in length from 17 inches to 16 inches and vice versa. It will also be noted that the tab folding fingers 191, 193, 195 and 197 are so dimensioned as to accommodate this very slight variation of 1/2 inch in tab width per each side of the lid where the carton size is 16 inches instead of the more customary 17 inches.

While the general operation of the machine is believed apparent, from FIGS. 1-11 inclusive, reference is now made to FIGS. 12a, 12b and 12c showing in ladder diagram form the electrical control system providing for automatic operation of the machine.

FIG. 12c shows the relative positions of FIGS. 12a and 12b with respect to each other while the table which follows describes the physical location of the various control sensors as well as their individual function in the sequence of operation. This method of description has been chosen for purposes of simplicity and clearness and to obviate the necessity for constant shuffling from one Figure of drawing to another in following the description.

__________________________________________________________________________ LINE PHYSICAL ITEM LOCATION FUNCTION LOCATION __________________________________________________________________________ PER-1 7, 13 INDICATES INCOMING AT INPUT END OF CARTONS CONVEYOR PER-2 13 INDICATES CARTON AT STOP NO. 2 AGAINST STOP NO. 2 LS-O 3 CONTROLS "ON-OFF" OF BELOW CONVEYOR CONVEYOR MOTOR LS-1 11, 23 INDICATES LID IS IN LEFT FRONT CORNER FEED POSITION OF LID LS-1A 11, 24 INDICATES LID IS IN RIGHT FRONT CORNER FEED POSITION OF LID LS-2 19 PREVENTS GLUING IF ABOVE FRONT CENTER NO LID IS PRESENT OF LID GUIDE LS-3 19 APPLIES GLUE TO ON REAR TOL-A- LEADING TABS MATIC MOUNTING BRACKET LS-4 20 APPLIES GLUE TO ON FRONT TOL-A- TRAILING TABS MATIC MOUNTING BRACKET LS-5 13, 18 INDICATES POSITION AT END OF MACHINE- OF LID PREVENTS END OF LID TRAVEL DOUBLE FEEDING LS-6 9, 13 INDICATES END OF UNDER TOP CROSS UPWARD TRAVEL OF MEMBER AND ABOVE CONVEYOR PRESSURE PLATE LS-7 13, 15, 18 INDICATES POSITION OF BELOW CONVEYOR CONVEYOR CR1 16 CONTROLS SOL NO. 1, STOPS NO. 1 CR2 17, 18 CONTROLS SOL. NO. 2 STOP NO. 2, PERMITS LID FEEDING DURING CARTON FEEDING CR3 8, 10 DROPS OUT STOP NO. 2 TO PERMIT DISCHARGE OF LIDDED CARTON CR4 12, 18 ASSURES LIDS ARE IN PROPER POSITION FOR FEEDING CR5 14, 21 CONTROLS SOL. NO. 5 AND CONVEYOR RAISE AND LOWER TD1 22 MAINTAINS UP POSITION UNTIL GLUE IS SET __________________________________________________________________________

In many instances it will be desired to incorporate the machine in production lines which are multi-purpose so that the cartons may or may not be lidded and if not lidded, may simply pass through the machine. Thus switch No. 1 may be closed which energizes solenoid MCR which in turn energizes the conveyor motor relay CM. With the conveyor in the down position, limit switch LS-0 is closed and the conveyor runs continuously so that carton bottoms simply pass through the machine.

When, however, the lidding function is to be incorporated in the production line, switch No. 2 is closed to connect power from the source to line 1. The lift motor solenoid LM is closed and lift motor for the lid elevator (not shown). This motor runs continuously and operates the lift elevator through the electric clutch-brake mechanism 25. This mechanism is an "off the shelf" item which operates as an intermittent drive mechanism to raise the lid blank elevator in step by step fashion as each lid blank is removed from the stack.

As the stack is raised the topmost lid blank opens switches LS-1 and LS-1a disengaging the drive through the clutch-brake mechanism because this lid is in position for feeding. The drive disengagement is effected through solenoid 6.

The carton meanwhile enters the unit and as it does it interrupts the light beam between sources 125 and 127 and reflectors 129, 131. As the first beam is interrupted line 10 is energized and control relay CR1 operated to admit pressure to the lifting jack for stop roll 124. The stop roll 124 lifts to stop the entry of additional cartons into the lidding area. At the same time, control relay 2 is energized to raise stop roll 121 to stop the carton in lidding position on the lifting conveyor.

Simultaneously with the actuation of the carton stop rolls, solenoid 3 is energized to begin feed of the topmost lid blank from the stack. The lid then contacts limit switch LS-2 which is an override to assure that the glue sequence will not function unless a lid blank is disposed beneath the glue applicators.

As the lid blank moves from the stack the feed arm 81 closes limit switch LS3 and the glue system is operated to deposit glue on the tabs 101 and 102 through applicators 47 and 49. As the lid blank advances further limit switch LS4 is closed and the glue application is repeated on tabs 103, 104. The lid blank advance continues until the feed arm contacts limit switch LS5. This switch opens because the lid blank is in its proper position over the carton bottom 120 and under presser plate 140. The solenoid control for the pusher arm jack then operates to retract the pusher and the brake-clutch mechanism 25 operates to raise the lid blank stack to place another lid in the "ready" position against limit switches LS1 and LS1a.

With the interruption of both light beams the sensors are dark. With a lid in position against limit switch LS5, control relay CR5 is energized to admit pressure to the conveyor lifting jack 60 via operation of a solenoid 5 which in turn operates a suitable fluid control valve. At the same time, a time delay relay TD1 is closed. With the conveyor lifting, limit switch LS-0 is opened and the drive motor for rollers 59 is turned off.

The carton bottom 120 continues its upward movement against presser plate 140 and as the plate rises the tab folding fingers 191 et seq. begin to fold the tabs 101 et seq. as shown in FIG. 6. Continued upward movement lifts the presser plate 140 and it first contacts the ends of spring lever arm 167, 169, the roll groups 149, 149' and 153, 153' begin to move toward the carton folding down the end flaps 75. As the upward movement of presser plate 140 continues the plate now contacts the ends of spring lever arms 168, 168', 171, 171' so that folding of the side falps 77 begins. It is noted, again, that having spring arms 167, 169 (which control closing of the end flaps) contact presser plate 140 before it actuates arms 168, 171 permits the end flaps 75 with the attached tabs 101, 102 et seq. to close slightly ahead of side flaps 77 to assure of full closure of the flaps against the filled tray 120 before adhesion occurs. FIG. 7 illustrates this step and shows how the tabs 101 et seq. are tucked under the side flaps 77. The upward movement continues until the FIG. 8 position is reached. At this point, the spring arms are transmitting maximum pressure to the flap forming roll groups. The upward movement stops as the limit switch LS6 is opened which energizes control relay CR3, de-energizes control relay CR2, thus the stop roll 121 drops down. The time delay relay holds the carton in the sealing position a sufficient period to assure complete adhesion of the adhesive on tabs 101 et seq. to set. After this period expires TD1 opens de-energized solenoid 5 and the lidded carton and the lifting conveyor drop down to close limit switch L-0 starting rollers 61 to convey the carton out of the machine and the cycle is completed.

Referring back to FIGS. 5 et seq., it should be noted that the reason for using roll groups to fold the flaps instead of just four unitary rolls, is that there may be some misalignment or out of squareness of the carton. The groups of rolls more readily accommodate to this condition.

Having described the invention in its preferred embodiment, it will be apparent that changes will occur to those skilled in the art which fall within the spirit and scope of the inventive concept which is limited only as defined in the claims, wherein:

Claims

What is claimed is:

1. In a lid forming device for forming and attaching flat lid blanks to a pre-filled carton bottom having vertical and parallel end walls and wherein said lid is provided with marginal side and end flaps and corner tabs attached to the end flaps, the improvement wherein said folding means includes a presser plate for pressing the lid down, a lifting means for raising the filled carton against the under surface of said lid to move said presser plate upwardly; roll means actuated by said presser plate to fold said side and end flaps inwardly toward the carton walls and means acting on said tab means to fold same downwardly before said roll means contacts and while said roll means is folding said flaps whereby said corner tabs are tucked under said side flaps when the flaps are pressed against the vertical walls of the pre-filled carton bottom.

2. A lid forming device of the structure defined in claim 1, wherein said tab folding means comprises a plurality of rigid fingers disposed above the corner tabs and engaged thereby as the carton and lid are raised by said lifting means.

3. A lid forming device of the structure defined in claim 1, wherein said roll means comprises a plurality of inwardly swingable rolls, and means contacting said presser plate whereby the rolls are swung inwardly coincident with upward movement of said presser plate and contact said flaps on a line disposed below the fold juncture of the flaps and lid defining area as the flaps contact said walls of said carton bottom.

4. A lid forming device of the structure defined in claim 3, wherein said presser plate contacting means comprises a plurality of spring arms connected with said rollers and having free ends adapted to contact the upper surface of said plate.

5. The lid forming device as defined by the structure of claim 4, wherein the terminal ends of the spring arms for the side flap folding rollers contacts the upper surface of said presser plate after said fingers have initiated downward folding of said corner tabs and after the end flap forming rollers have begun downward folding of said end flaps by said end flap folding rollers.

6. A filled container lidding device for folding flat lid blanks having end and side flaps and corner tabs carried by said end flaps into engagement with the sides of a filled container comprising; a frame, a lid blank supply station, means comprising spaced pairs of guide members for guiding said flat lid blanks first vertically upwardly, then laterally, edgewise to a position overlying a filled container, means for lifting said container into contact with said lid; oppositely spaced means for folding said corner tabs and said end and side flaps into tight contact with said container walls; means supporting said oppositely spaced flap folding means and said spaced pairs of vertical lid guiding means on said frame for relative motion with respect to one another whereby lid blanks of different dimensions may be loaded on said lid supply station and moved vertically and laterally edgewise and thereafter the end and side flaps and corner tabs folded into engagement with the container walls of a correspondingly dimensioned container and means for operating said supporting means to accomodate containers and lids of compatible dimensions.

7. A filled container lidding device as set forth in claim 6 wherein said supporting means comprises two pairs of parallel horizontal rack bars slidably mounted on said frame; a pinion in contact with each of said pairs of rack bars and means for rotating said pinion back and forth to cause equal and opposite movement of the bars in each pair of said rack bars.

8. A filled container lidding apparatus as defined in claim 7, wherein one each of the opposite pairs of blank guides and flap folding means is mounted on a single rack bar and moved by said bars in equal and opposite directions.

9. An apparatus for applying lid blanks having side and end marginal flap areas and corner tabs carried by either of said flap areas to filled containers comprising means for supporting a supply stack of flat lid blanks in a horizontal position; means for laterally moving individual, flat lid blanks one at a time from the top of said stack on said supporting means to a position overlying a filled container; means for applying adhesive to the corner tabs of said lids during said lateral movement; means for supplying individual filled containers to a position directly beneath the individual flat lid blank; means for lifting said filled container into contact with the flat lid blank; means for bending said corner tabs downwardly as the filled container contacts said blank, further means operable by continued upward movement of said blank and filled container for bending the marginal flap areas downwardly after the container contacts said lid blank whereby said corner tabs are disposed beneath said folded marginal flap areas; said folding means comprising pivoted roller pressing said marginal flap areas downwardly and upon continued movement pressing said flap areas against the side walls of said filled receptacle at the juncture of said flap areas to the remainder of said blank, and means for discharging said lidded carton from said apparatus after said lid has been applied thereto.

10. An apparatus as defined in claim 9, including presser plate means contacting the upper surface of said flat lid blank as the filled container is lifted to press the lid tightly against the contents of the container.

11. An apparatus as defined in claim 9, wherein the means for supporting the supply of flat blanks comprises an elevator platform, and means to incrementally raise said elevator platform in response to removal of individual blanks from said stack of flat lid blanks.

12. An apparatus as defined in claim 9, wherein said means for laterally moving said flat blanks comprises a pair of horizontal support rails engaging the under surface of the individual blanks and a pair of self-aligning feeder tongues movable parallel to said rails and having means to engage the edge of each individual blank to move same laterally from said stack along said rails to the position overlying said filled container.

13. An apparatus as defined in claim 12 wherein said means to engage the edge of each of said blanks includes an outwardly projecting pin adapted to enter the edge of the lid blank.

14. An apparatus as defined in claim 12 including further a pair of guide means disposed adjacent each rail and said guide means including a frictional means for engaging the edges of the laterally moving blanks.

15. An apparatus as defined in claim 9, wherein said container lifting and discharging means includes a vertically moving roller conveyor having means to power said conveyor rolls when said conveyor is at its lowermost position.

16. An apparatus as defined in claim 9, including automatic control means for controlling said means for moving said filled container, said lid blank feeding means, said container lifting and discharge means and said flap bending means in repetitive sequence in response to the presence of a filled container in an initial position beneath said flat lid blank.