US3194126A - Method and mechanism for aligning glued carton blanks - Google Patents

Description

July 13, 1965 o. E. LARSSON 3,194,125

METHOD AND MECHANISM FOR ALIGNING GLUED CARTON BLANKS Filed April 22, 1963 3 Sheets-Sheet 1 July 13, 1965 o. E. LARSSON 3,194,125

METHOD AND MECHANISM FOR ALIGNING GLUED CARTON BLANKS Filed April 22, 1963 3 Sheets-Sheet 2 July 13, 1965 o. E. LARSSON 3,194,125

METHOD AND MECHANISM FOR ALIGNING GLUED CARTON BLANKS Filed April 22, 1963 3 Sheets-Sheet 3 United States Patent 0 This invention relates to a method and a mechanism for aligning carton blanks and the like which are c0ntinuously advanced one after the other in a machine while passing a folding device in which the side parts of the blank are folded in toward the central part thereof and glued together, during which operation an undesirable distortion of the edges of the side parts relative to the edges of the central part is likely to occur. The aligning operation is intended to be performed before the adhesive has completely dried, and the object of this invention is to provide an improved method and an improved mechanism for aligning the glued carton blanks.

As previously known aligning mechanism comprises a stop member toward which the blanks are fed and a jogging member located ahead of the stop member at a distance therefrom equal to the length of a carton, the jogging member engaging the trailing edges of the carton blank and being adapted to force the blanks toward the stop member. Generally, this operation takes place while the carton blanks are being fed horizontally to the aligning station on a conveyor consisting of rubber belts or the like from which they are advanced during alignment to conveyor which makes an angle of 90 with the first named conveyor.

In this mechanism the jogging member consists of a relatively long, movable vertical plate adapted to make an oscillating movement such that the carton blanks during their forward movement are subjected to a plurality of impacts between the jogging member and the stop member under the action of which the aligning operation is performed. Consequently, this known mechanism is based on the principle that the carton blanks are horizontally advancing during the aligning operation.

However, this method of aligning results in a plurality of considerable inconveniences. Since the carton blanks must have time to dry before the final stacking and the discharge of the finishing stack can take place, the most important disadvantage consists in that the conveyor for the carton blanks advanced in rapid succession must be of a considerable length. If the adhesive has not dried sufficiently there arises the risk of a renewed distortion of the side parts relative to the main part of the blanks because of the stresses acting on the carton blanks during the stacking operation. In view of the high velocity at which the carton blanks are advancing on the conveyor they will travel a considerable distance during the time required for drying, and the length of the carton l manufacturing machine has to be adapted accordingly in order to permit the desired high advancing velocity.

The above inconvenience is entirely eliminated by the method according to the present invention which is characterized by placing the blanks after the gluing operation and before the adhesive has dried, in a stack, actuating the leading and trailing edges of the blanks at least as they enter the stack by jogging members adapted to urge said leading and trailing edges to parallel positions, and

" retaining the blanks in the stack until the adhesive has dried enough to have the positions of said edges definitely fixed.

Due to the fact that the carton blanks form a substantially vertical stack during the time required for the 3,Il9d,l2 Patented July 13, 1965 adhesive to dry sufficiently it will be obvious that the horizontal length of the carton manufacturing machine can be considerably reduced as compared with previously known similar machines. In addition to the reduction of the required space for the machine the manufacturing cost of the machine is considerably reduced due to the fact that a great number of rollers, rubber belts and other appertaining members of conventional machines can be omitted.

Further, the aligning operation can be performed in an improved manner, since the carton blanks can be aligned by elements forming part of the aligning mechanism all the time during which the carton blanks are passing through the stack. In other words in using the method according to the present invention the blanks have no possibility to resume their previous non-aligned form before the adhesive has dried enough to have the carton blanks fixed.

Supposing that it were desired to double the productivity of a carton manufacturing machine by doubling the feeding speed and assuming other factors to be constant it will be obvious that in case of a conventional machine in which the length of the conveyor beyond the aligning mechanism is for instance 22 yards the length of the conveyor had to be increased to 44 yards. In contrast thereto, in a mechanism according to the invention it would merely be necessary to increase the height of the stack from for instance 3 feet and 4 inches to 6 feet and 8 inches whereas the rest of the machine could remain unchanged.

The aligning mechanism is preferably provided at the stop member with a guide for correct feeding the leading edge of the carton blank toward the stop member. By way of example this guide may consist of a curved plate which forces the leading edge of the carton blank to be aligned against the stop member between the plate and the uppermost carton blank of the stack resulting in that the leading edge of each blank will come into contact with the stop member at substantially the same place. Consequently, the. distance between the jogging member and the stop member which should be variable in accordance with the sizes of the carton blanks can be determined in exact conformity with the blanks so as to obtain a very favourable result of the aligning mechanism.

The jogging member may consist of a toothed rotary roller the teeth of which clutch the trailing edge of a blank and move said edge forward and downward along the arc so as to force the leading edge against the stop member and to align it whereupon during continued movement of the toothed roller the trailing edge of the carton blank is disengaged therefrom.

The jogging device may instead comprise two or more substantially vertical plates adapted to oscillate in an oblique forward and inward direction toward each other while oscillatingly urging the leading edges of the blanks against the stop member.

However, in accordance with a preferred embodiment the aligning mechanism is constituted by a combination of the two above named jogging devices, the toothed rollers being preferably adapted for coarse alignment and the vertical plates being adapted for fine alignment of the carton blanks.

This double aligning operation has proved to be very successful. Further, the parts of which the aligning mechanism consists are very easy to manufacture and the necessary movements of the parts can be obtained in a simple manner. In particular, the continuously working vertical plates result in that the carton blanks in the stack are subjected to a continuous aligning action during all the time required for fixing the carton blanks a this being an essential condition of the favourable result of the aligning operation.

Other features and advantages of this invention will appear from the following detailed description of an embodiment thereof. The specification describes an example only of the invention with reference to the annexed drawing in which FIGS. 1a and 1b are lateral elevations of the fore and intermediate part respectively of a carton manufacturing machine. In FIG. 2 which is a top view of the same parts several irrelevant elements are omitted and other elements, such as the vertical plates are partly exposed for the sake of clearness although they are concealed in reality. Further, the figures have been shortened by a central section. FIGS. 3 and 4 illustrate to an enlarged scale some parts important to the invent-ion and corresponding to similar parts in FIGS. 1b and 2, respectively.

Referring to the drawing, M denotes the uppermost carton blank in the stack from which the blanks are fed to the carton manufacturing machine. The remaining blanks in the stack are denoted at 112, 1c and 1d the last named blank 1d being the lowermost blank which is about to be discharged from the stack. denotes the lowermost but one blank to be forwarded after the blank 1d. A carton blank the tab 1x of which is coated with adhesive is denoted at 12. A carton blank the side parts of which are turned down to vertical positions if denoted at 1 and 1g denotes a carton blank the side parts of which are being folded together. llh denotes a carton blank which in a short time arrives at the aligning mechanism, 1i denotes a blank during coarse alignment and the carton blanks piled one on top of the other in the fine alignment mechanism are denoted at lj. Finally, 1k denotes a completely aligned carton blank discharged from the stack. After a blank has arrived on a conveyor adhesive is applied to the tab 1x at one of the side parts of the carton blank (FIG. 2) by means of a roller 17 which receives adhesive from a container 18. In FIG. 1 the carton blank to which adhesive is applied is denoted at 1e. After application of the adhesive folding of the side parts 132 and lz is started and effected by means of two helical rods 19 while the blanks are travelling forward on the continuously running rubber belts 26. In FIG. 1 the carton blanks If and 1g are shown in different stages of the folding operation.

I It should be pointed out that the carton manufacturing machine illustrated is devised such that the side parts are folded downward, this being of great advantage as compared with construct-ions of previously known design in which said parts are folded upwards. Due to the downward folding the carton blanks can be delivered directly to the machine from a printing press where inscriptions and/ or pictures are applied without the necessity of turn ing over the blanks. This improvement is due to the special design of the folding rods 19 shown in FIGS. 1a and 1b.

After the side parts ly and 12: have started the folding -movement outward each other the central part comprising the sections 1p and lq is guided by bordering belts 25. Should the central part of the carton blank during the folding operation of the side parts have deviated from the direction of feed this fault will be corrected by the bordering belts. These belts consequently assist in minimizing distortion of the edges of the side parts relative to'the edges of the central part during the final folding operation which precedes the final gluing. It is not possible, however, entirely to eliminate such distortion before the blank passes between pressure rollers 2% where the previously coated tab 1x of the side part 1y of the blank is bonded to the opposite side part lz. Consequently a certain distortion of the side parts relative to the central part will remain after the blank has passed the pressure rollers 26. In the technical language it is a common saying that the side parts are forming a snowplough.

The purpose of the aligning operation is to eliminate this distortion so as to give the carton blanks the same form as the blank 1k which means an exact alignment of the central part of the carton blank with the side parts or wings thereof. The aligning mechanism consists of an abutment or stop member 3 and a jogging device located at a distance therefrom equal to the length of a carton and comprising two complementary elements. One of these elements is the toothed roller 4, (FIGS. 3 and 4) and the other element comprises vertical plates 5 (FIG. 4). The toothed roller is continuously rotating whereas the vertical plates are adapted to oscillate in an oblique forward and inward direction toward each other. During rotation of the toothed roller 4 the teeth thereof clutch the trailing edge of the carton blank 11' and move this edge forward and downward along an are so as to force the leading edge into contact with the stop member 3. As a result, the carton blank will be momentarily held between the toothed roller and the stop member, and first of all the oblique side parts will be forced against the stop member so as to counteract the distortion. After the point of the roller which engages the trailing edge of the blank has passed its foremost position a downward vertical movement is imparted to the trailing edge and upon continued rotation of the toothed roller the trailing edge of the blank will be disengaged therefrom and moved down onto the stack c of carton blanks. It will be seen that the toothed roller forms part of a stacking device by means of which and under the action of gravity the carton blanks are moved downward and form a stack. During their downward movement in the stack the blanks are then continuously acted upon by the vertical plates.

If after the primary alignment by the toothed roller 21 certain distortion remains it will be eliminated by the vertical plates which supplement the coarse aligning effected by the toothed roller. The distance between the stop member and the toothed roller may even be so great that on purpose a certain distortion remains after the coarse alignment by the toothed roller 4 which distortion is then eliminated by the fine alignment device in the form of the vertical plates.

At the top of the stop member there is provided a guide 2 which guides the leading edge of the entering blank such that the blank will be moved toward the upper end of the stop member between the guide and the uppermost blank of the stack. The guide consists of an upwardly concave plate. Associated with the toothed roller 4 is a plurality of spring leaves 6 which assist in guiding the leading edge of the blanks as it moves toward the stop member and also facilitate engagement of the toothed roller with the trailing edge of the blank.

After coarse alignment between the toothed roller 4 and the stop member 3 the blank is moved down between a plurality of substantially vertical plates 7. The stack of blanks is disposed between the plates 7 and the stop member. The distance between the rear plate 7 and the stop member 3 is slightly greater than the length of the carton blank so that there is sufficient place between the rear plate 7 and the stop member 3 even for the only coarsely aligned blanks having still a certain distortion between the side parts ily and lz and the part 1p, 1q. As mentioned above the carton blanks are acted upon during their downward movement in the stack by the fine alignment device in the form of the vertical plates 5 which oscillate in an oblique forward and inward direction toward each other. Similar to the preceding coarse aligning operation the leading edges of the blanks are forced against the stop member, which per se results in an aligning operation. However, the forward and inward movement of the plates results in an additional aligning movement because of the fact that the plates directly act upon the oblique lower side parts ly and lz of the coarsely aligned carton blankin a direction in which they shall move to secure complete alignment of the blank. As a result the carton blank will be completely aligned as soon as it comes into contact with the fine aligning device at the upper part of the stack. Any tendency of the side parts of the carton blank to return to their previous nonaligned positions is counteracted by the fine aligning members 5 all the time required for the movement of the blank from the top to the bottom of the stack during which movement the adhesive has time to dry enough to have the positions of the edges of the blank definitely fixed.

The movement of the fine aligning device 5 is derived from two eccentrically mounted pins 23 (FIG. 4) which act upon the rear edges of horizontal rods 22 connected to the plates 5. The rods are directed toward each other and make an angle of about 45 with the direction of feed. The movement of the rods is guided by a plurality of rotary rollers 24. The return movement from the foremost position takes place under the action of springs indicated in the drawing. Alternatively, the rods may be provided at the eccentric pins 23 in which case the rear rollers 24 are omitted. The eccentric pins rotate at a comparatively high speed so as to impart to the vertical plate a relatively rapid oscillating motion in an oblique forward and inward direction.

The finally aligned carton blanks are discharged substantially horizontally one by one from the lower part of the stack by means of a discharging device 8, 9, 10, which is based on the same principle as the feeding device at the fore part of the machine, but is not devised in an exactly similar manner.

The blanks are discharged substantially in timed relation to the downward movement of the coarsely aligned blanks to the top of the stack.

A detent 11 acts to prevent discharge of blanks in the event of the height of the stack of blanks being smaller than a predetermined value. Otherwise the carton blanks would pass through the stack before the adhesive has sufiiciently dried. The guide 2 at the upper part of the stop member is pivotally mounted on a horizontal shaft and devised as a feeler 12 which has the double function of guiding the movement of the leading edge of the blank toward the stop member and of ascertaining the height of the stack. If there are too few cartonblanks in the stack, that is, if the stack is too low, the feeler 12 falls under the action of gravity forward and downward and thereby sends a signal to the detent 11 which puts the discharging device out of function until the stack is of sufficient height. In the embodiment illustrated in the drawing the detent consists of a spring leave 11 provided at one end of a lever 12. At the other end of the swingable lever 12 there is secured the armature 14 of an electromagnet 15. As mentioned above if the height of the stack is not sufificient the combined guide 2 and feeler 12 are lowered forward under the action of gravity with the result that an impulse is emitted to the electromagnet 15, which attracts the armature 14. The other end of the lever moves upwards and prevents the lowermost blank from coming into contact with the continuously running rubber belts below the stack so that no blank can be discharged from the stack. As soon as the stack is sufficiently high the current to the electromagnet is broken whereupon the lowermost blank can be discharged in the regular manner.

The finally aligned carton blank 1k is then fed to a stacker, not shown in the drawings.

The blanks are advanced to the stop member 3 by means of the pressure rollers which also press the side parts of the blanks against the central part prior to the aligning operation. A rubber roller 21 cooperating with the toothed coarse aligning roller 4 also assists in advancing the carton blank toward the stop member except for the very last step of movement during which the toothed roller 4 solely feeds and simultaneously aligns the carton blanks.

The stop member 3, guide 2, detent 11 and associated members are movable relative to the aligning members to permit adjustment in accordance with ditferent sizes of cartons. If desired, the vertical extension of the stop member 3 and the rear plates 7 may be varied to obtain different heights ofthe stack. To this end, the stop member and the rear plate may consist of a plurality of detachable parts which are removable and exchangeable for other corresponding parts of greater or smaller lengths.

resilient so that the blanks afterhaving been moved down' by the toothed roller 4 are held between. the rear plate and the top member and then are moved down by the next succeeding blank after the corresponding alignment and downward movement thereof. If the stop member is resilient it may consist of a fixed part and a plurality of smaller resilient parts projecting therefnom which resilient parts during the aligning operation of a blank are forced back toward the fixed part and after downward movement of the rear edges of the blanks into contact with the rear plate keep the blanks in engagement with the rear plate. It will also be understood that the carton blanks can be brought to pass upwardly in the stack in which case a toothed roller disposed below the stack can be used as an aligning member. In this modification the stop member is suitably of different construction and may comprise, for example, a plurality of dogs or the like which are movable downward below the conveyor as the final stack is released.

It will also be seen from the drawing that, for instance, the stop member and the rear plate are not exactly vertical but slightly sloping. The slope is due to the construction of the other parts of the machine and is not relevant to the present invention. Although not specifically indicated in this connection the words vertical and horizontal generally include the words substantially vertical and substantially horizontal in the specification and claims.

What is claimed is:

l. A mechanism for squaring up carton blanks and similar relatively stiff blanks having fold or crease lines, said blanks being continuously advanced one after the other in a machine while passing a folding device in which the side parts of the blanks are folded in toward the central part thereof and glued together during which operation an undesired distortion of the edges of the side parts relative to the edges of the central part tends to occur, which mechanism comprises a fixed stop member toward which the blanks are fed; a profiled rotary roller located at a distance from the stop member equalling the length of a blank, said roller being adapted to clutch the trailing edges of a blank and to move said edges forward along an are so as to force the leading edge of the blank against the stop member to squareup the blank, said roller upon continued rotation delivering the blanks to a stack.

2. A mechanism as defined in claim 1, said profiled roller being located above the stack.

3. A mechanism as defined in claim 1, in which said profiled roller is a toothed roller.

4. A mechanism as defined in claim 1, in which said I profiled roller is a fluted roller.

5. A mechanism as defined in claim 1 and comprising at least two substantially vertical plates located at a distance from the top member equalling the length of a blank, said plates being adapted to oscillate in an oblique forward and inward direction toward each other while oscillatingly urging the leading edges of the blanks in the stack against the stop member.

6. A mechanism as defined in claim 1,. and compris ing spring means associated with the rotary roller and adapted to guide the leading edges of the blanks as they pass toward the stop member and to facilitate engagement of the profile of the roller with the trailing edges of the blanks.

7. A mechanism as defined in claim 1 and comprising guide means for moving the leading edges of the carton blanks toward the stop member.

3. A mechanism as defined in claim 1 and comprising a fixed substantially vertical rear plate at a distance from the stop member slightly exceeding the length of a blank, the stack of blanks being accommodatable in the space between said fixed rear plate and said stop member.

9. A mechanism as defined in claim 2, and compris- References Cited by the Examiner UNITED STATES PATENTS 3,030,867 4/62 Wright 93-36 3,087,725 4/63 Duncan 27171 FRANK E. BAILEY, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,194,126 July 13, 1965 Olof Einar Larsson It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 6, line 68, for "top" read stop Signed and sealed this 21st day of December 1965.

(SEAL) Attest ERNEST W. SW'IDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents

Claims (1)

1. A MECHANISM FOR SQUARING UP CARTON BLANKS AND SIMILAR RELATIVELY STIFF BLANKS HAVING FOLD OR CREASE LINES, SAID BLANKS BEING CONTINUOUSLY ADVANCED ONE AFTER THE OTHER IN A MACHINE WHILE PASSING A FOLDING DEVICE IN WHICH THE SIDE PARTS OF THE BLANKS ARE FOLDED IN TOWARD THE CENTRAL PART THEREOF AND GLUED TOGETHER DURING WHICH OPERATION AN UNDESIRED DISTORTION OF THE EDGES OF THE SIDE PARTS RELATIVE TO THE EDGES OF THE CENTRAL PART TENDS TO OCCUR, WHICH MECHANISM COMPRISES A FIXED STOP MEM-

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