US3130967A

US3130967A - Hopper feed for carton blanks

Info

Publication number: US3130967A
Application number: US161129A
Authority: US
Inventors: Brell John Le
Original assignee: Alton Box Board Co
Current assignee: Alton Box Board Co
Priority date: 1961-12-21
Filing date: 1961-12-21
Publication date: 1964-04-28
Anticipated expiration: 1981-04-28

Description

April 28, 1964 J. LE BRELL HOPPER FEED FOR CARTON BLANKS 2 Sheets-Sheet 1 Filed Dec. 21, 1961 mum/r02. (/MN 45 3,6514 J e panda/M439 April 28, 1964 J. LE BRELL HOPPER FEED FOR CARTON BLANKS 2 Sheets-Sheet 2 Filed Dec. 21, 1961 hwavme: (fa/{Iv 4/5 51861: W pw/mm4 United States Patent 3,130,967 HGPPER FEED FOR CARTGN BLANKS 501m Le Brell, Hermann, Mm, assignor to Alton Box Board Company, Alton, 111., a corporation of Delaware Fiied Dec. 21, 1961, Ser. No. 161,129 8 Claims. (Cl. 271-62) This disclosure relates generally to machines for setting up folding cartons, and is particularly addressed to the portion of a machine which holds a supply of unfolded blanks.

It is common practice to manufacture cartons from precut and scored blanks of paperboard or similar material. The unfolded blanks are conveniently shipped and stored in stacks, and a machine is commonly employed to fold the blanks into finished cartons at the point of use. Many such machines incorporate a magazine, hopper or other device for holding a supply of unfolded blanks, which are fed automatically to the folding mechanism. Customarily, the blanks are arranged in a stack with the machine drawing single blanks from one end and a machine tender or worker replenishing the supply from time to time, by adding blanks in groups to the other end of the stack.

A common arrangement is to provide inclined rails with the blanks riding at their lower edges on the rails and a heavy back-up weight also riding on the rails to maintain pressure on the back of the stack and move the stack forwardly as individual blanks are pulled by the machine from the front of the stack. The weight is pulled back when a group of blanks is to be added to the supply. The heavy weight type of blank feed avoids certain problems encountered with positive blank feeds, but does present a problem in providing sufficient forward force without becoming awkward to manipulate when the machine tender adds to the supply. Accordingly, an

object of this disclosure is to provide an improved feed system for stacked blanks in a carton set-up machine, and more particularly to provide a system in which the forward thrust on the blanks is, in part, independent of the weight of the back up member or angle of the rails, which hold the stacked blanks. In addition, the disclosure provides a system particularly useful in handling waxcoated blanks, such as those used in packaging frozen foods, since wax tends to accumulate upon guide rails and interfere with operation.

In the attainment of these objectives, briefly, the mechanism herein disclosed comprises bottom rails and side rails which engage the bottom and side edges of a stack of blanks. The rails are in the form of rods, which are rotated continuously in predetermined directions. The bottom rods are rotated in opposite directions, so as to offset side thrust and the side rods may produce a downward thrust.

The surfaces of the lower rods are roughened in a spiral pattern, as by moving emery cloth down a rod as it is rotated in a lathe. This spiral grain acts upon the blanks much like a screw or thread to move the blanks along the rods, but the grain is slight, so that there can be relative motion between the blanks and rotating rods. Accordingly, the blanks are fed in the hopper by a frictional screw drive. A back-up member is employed to hold the blanks upright, and it is supported by wheels riding upon the rods. Some of these wheels are freely journalled with their axes crosswise of the rods, so as to rotate with the rods, and their effect is to permit or cause a slow forward progression of the back-up member along the rod. Accordingly, when the back-up member is pulled back from the blanks and released, it does not immediately slide back down against the blanks. Rather, there is a slow forward advance, which permits one to insert additional blanks without holding the back-up member away from the blanks already in the hopper. In this sense, the wheels act as a slipping brake, which automatically controls the movement of the back-up member during loading of the hopper.

The rate of advance of the blanks is determined by the spiral of the driving rods and their speed of rotation. The rate of advance of the back-up member may funther be determined by setting the wheels with their axes at a slight angle relative to the axes of the rods.

Other features of the invention will be in pant apparent from and in part pointed out in the following detailed description taken in connection with the accompanying drawings, in which:

In FIG. 1 is a side elevation illustrating a hopper embodying features disclosed herein;

FIG. 2 is a top plan view of the hopper;

FIG. 3 is a section taken on the line 3-3 of FIG. 1;

FIG. 4 is a section taken on the line 44 of FIG. 1; and a FIG. 5 is a section taken on the line 5-5 of FIG. 1.

Referring to the drawings, there is shown a hopper or magazine for carton blanks B carried in an inclined stack. The blanks are supported at their lower edges upon a pair of parallel inclined rods 1 and are retained against lateral displacement by a second pair of parallel rods 3 disposed above and outwardly of the rods 1. The rods are journalled at their ends in a front header 5 and a back header 7, the arrangement being one wherein the rods slope downwardly to the front.

The blanks collect at the front of the unit and are held upright in a stack by a back-up member of follower 9, which is movable over the rods. An individual blank is drawn from the front of the hopper, as by a suction cup C or set of cups, and is carried thereby to a folding mechanism, such as a plunger and die (not shown).

It will be understood that this magazine forms part of a larger machine for automatically forming blanks into cartons and such machines operate at high speeds. As the blanks are withdrawn individually, the stack moves forwardly. Intermittently, the supply of blanks is replenished by pulling back the follower and manually inserting additional blanks behind those already in the magazine. This disclosure is particularly concerned with the problems of simplifying the reloading operation and feeding the blanks forwardly on the rods.

More particularly, the lower rods 1 have collars 11 secured to their forward ends, and the collars act as stops limiting the forward movement of the stacked blanks.

A front framework 13 also carries stop fingers 15 at the sides of the front blank and an upper guide and stop assembly 17 The suction cup is adapted topull the lower part of the front blank over the collars 11 and then pull the entire blank downwardly clear of the stop fingers 15 'and assembly 17, the blank being then moved to the folding or forming mechanism. These details are not significant to the present disclosure, hence are not further described.

The rods are otherwise journalled and project through bearings 19 fastened to the back header 7. The projecting end of each rod carries a sheave, there being sheaves 51 and 52 on the lower rods 1 and sheaves 53 and 54 on the outer rods 3 (FIG. 5). A driving belt 21 is trained about the sheaves 51, 52, S3, 54, and this belt also passes about idler sheaves 55 and 56 and a drive sheave (not shown). It may be noted the belt passes over sheave 53, under sheave 51, over sheave 52 and thence under and about sheave 54, so that the two lower rods 1 are driven in opposite direction and so that the two upper rods 3 are likewise driven in opposite directions. As indicated by the arrows of FIG. 5, the directions of rotation are such that the outer rods 3 tend to exert a slight downward thrust on the blanks at their side edges, whereas the side thrust of one lower rod counteracts that of the other lower rod. However, the outer rods might be driven in such a way as to exert a lifting force on the blanks.

The rods are rotated continuously, and this is desirable in'feeding waxed blanks, since there is then a minimum of wax build up on'the rods, such as would interfere with the feeding of the blanks. Also, the rotation of the rods is herein utilized to produce .a forward feeding force on the blanks. This is accomplished by giving the lower rods a slight surface roughening in a helical or screw-like pattern. The degree of roughening is that obtained when a piece of emery cloth is pressed against a rod and moved longitudinally while the rod is rotated in a lathe. This roughening is to be distinguished from a true thread or screw because a slipping or frictional drive, rather than positive drive is desired. The'forward feed should necessarily be sufiicient to compensate for the withdrawal of blanks by the suction cup, and will depend upon the pitch of the grained surface and thespeed of rotation. The latter may be varied, but preferably is proportional to the rate at which blanks are withdrawn and the rate at which cartons are formed. In other words, the belt 21 would be driven in synchronism Withthe other mechanism of the machine.

With the blanks being fed by the rods, the forward force exerted by the follower 9 need not be nearly as great as would be necessary were the follower to supply all of the blank feeding force. Indeed, the follower merely serves to hold the blanks upright at the back of the stack, the blanks at the front of the stack'being held upright by the

parts

15 and 17.

Moreover, the follower is supported so that it tends to move forwardly at a rather slow speed, not much greater than the rate of blank advance and much slower than would be the case were it free to roll or slidefreely down the rods. When the follower advances slowly, it may not be necessary to hold it back while replenishing the supply-in a sense, the follower holds itself back for a delayed interval. Even if it is necessary to hold the follower, only a light force is required.

The follower is carried by four rollers 23, two at each side, over the outer rods 3. .A lower roller 25 is disposed below .each rod 3 between the two upper rollers 23 for that rod. The rollers 25 have their axes perpendicular to the axes of the rods, whereas the rollers 23 are journalled with their axes approximately (but not exactly parallel to the rods. Otherwise, the follower is retained agianst lateral displacement by nylon discs 27 between the lower rods 1. These discs may be fixed by bolts, which are eccentric with respect to the periphery of the discs, so that the angular adjustment of thediscs will take up any slack.

When the rods are rotating, the follower is carried by the rollers 23, which rotate with the rods. The rollers 25 are used only to keep the follower from coming off the rods when it is pulled back. The rollers 23 prevent the follower from rolling down the rods. Rather, the rollers 23 control the rate of forward advance. This rate of advance can, in turn, be controlled by disposing the roller with their axes at a slight angle (say from'true parallel with respect to the rods. The arrangement is one assuring a forward advance of the follower, but at slow rate. The actual rate of advance may depend in part upon other factors, such as incline of the rods and weight of the follower.

It is not practical to give exact relationships, but they can be readily worked out for a given machine in the light of this disclousre. Indeed, it will be apparent, the unit might be made with the rods horizontal, although some incline is helpful in keeping the blanks upright when the follower is pulled back.

Other variations and modifications will, no doubt, occur to those skilled in the art, without departing from the spirit of the disclosure, or scope of the claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

l. A hopper for carton blanks to be fed to a forming machine, the hopper having a first pair of rods upon which a stack of carton blanks is supported with the cartons resting on the rods at their lower edges, a second pair of rods extending generally parallel to and above and outwardly of said first rods in positions such that they may be engaged by the side edges of the blanks, said rods being journalled for rotation about their axes, means rotating each of said rods, and a follower carried by one of said pairs of rods, said one pair of rods being rotated continuously in opposite directions, and means forming a friction drive connection between said follower and its supporting rods for moving the follower therealong at a rate proportional to the rotational speed of the rods when the follower is not otherwise restrained, said friction drive permitting the follower to be pulled back from the stack of blanks and its rate of movement being sufiiciently slow to permit the follower to be released and a supply of blanks added to the stack before the follower returns to the stack of blanks.

2. A hopper for carton blanks to be fed to a forming machine, the hopper having means supporting a stack of blanks on their edges, friction feed means cooperating with the blanks to advance the stack toward one end of the hopper, a follower normally engaging the stack of blanks at its other end but retractable therefrom, friction feed means moving said follower in the same direction as the blanks, said blank feed means functioning independently of said follower, so that the blanks are fed even when the follower is retracted from the stack of blanks, and said follower feed means having a rate of advance slightly faster than that of said blank feed means.

.3. In apparatus for feeding articles in a predetermined direction, the improvement that comprises a cylindric rod mounted for rotation about its axis and disposed with its axis extending generally in said predetermined direction of feed with its surface in contact with said articles, means for rotating said rod, the surface of said rod being essentially smooth and free of threads and flights but for a plurality of fine scratches in a substantially helical pattern, said scratches being of a character produced by an abrading medium moved along the rod while it is turned, thereby to produce a surface which permits longitudinal slip between article and rod yet moves the article along the rod when the rod is rotated and the article is free of restraint.

4. In apparatus for feeding articles in a predetermined direction, the improvement that comprses a cylindric rod mounted for rotation about its axis and disposed with its axis extending generally in said predetermined direction of feed, means for rotating said rod, an article followermounted for movement along said rod, a wheel journalled in said follower in riding engagement with said rod, said wheel being disposed with its axis lying at an acute angle relative to the axis of said rod, whereby rotation of the rod causes rotation of the wheel and .the angled disposition of the rotating wheel moves the follower along the rod at a predetermined rate proportional to the speed of rotation of the rod and the angle of the wheel axis to the rod axis.

5. In a hopper for feeding carton blanks to a forming machine, the improvement that comprises a plurality of rods mounted for rotation about their axes and disposed to sustain a stack of carton blanks at their edges, means for rotating said rods, at least one of said rods having a cylindric surface free of threads and flights but for a plurality of fine scratches in a substantially helical pattern, whereby said rod will move the blanks along the rod when the rod is rotated and the blanks are free of restraint yet permit restraint of the blanks without damage thereto while the rod is rotating.

6. In a hopper for feeding carton blanks to a forming machine, the improvement that comprises a plurality of rods mounted for rotation about their axes and disposed to engage a stack of carton blanks at their edges, a follower mounted for movement along said rods in engagement with the stack of blanks, a Wheel journalled on said follower in riding engagement with one of said rods, means for rotating said rod about its axis, said wheel being disposed with its axis lying at an acute angle relative to the axis of said rod, whereby rotation of the rod causes rotation of the rotating wheel and the angled dis position of the wheel moves the follower along the rod.

7. Apparatus for biasing a stack of sheets toward one end of a predetermined path which is substantially parallel \m'th the thinnest dimension of the sheets, comprising a rod whose surface is substantially cylindrical, whose axis is substantially parallel with said path, said rod being arranged to sustain a substantial part of the weight of at least some of the sheets in said stack, the substantially cylindrical surface of said rod having a multiplicity of 6 scratches extending at an acute angle with an intersecting plane which is normal to the axis of the rod, and means for driving said rod in rotation about its axis.

8. The apparatus of claim 7 wherein there are two such rods spaced radially from each other and each engages the same edge of a sheet, said rods having their surface scratches reversely oriented and their direction of rotation opposite.

References Cited in the file of this patent UNITED STATES PATENTS 1,564,926 Armstrong et al. Dec. 8, 1925 1,971,574 Moon Aug. 28, 1934 2,193,942 Shackleford Mar. 19, 1940 2,642,285 Baker et al. June 16, 1953 2,869,715 Williams Jan. 20, 1959 2,872,190 French Feb. 3, 1959

Claims

1. A HOPPER FOR CARTON BLANKS TO BE FED TO A FORMING MACHINE, THE HOPPER HAVING A FIRST PAIR OF RODS UPON WHICH A STACK OF CARTON BLANKS IS SUPPORTED WITH THE CARTONS RESTING ON THE RODS AT THEIR LOWER EDGES, A SECOND PAIR OF RODS EXTENDING GENERALLY PARALLEL TO AND ABOVE AND OUTWARDLY OF SAID FIRST RODS IN POSITIONS SUCH THAT THEY MAY BE ENGAGED BY THE SIDE EDGES OF THE BLANKS, SAID RODS BEING JOURNALLED FOR ROTATION ABOUT THEIR AXES, MEANS ROTATING EACH OF SAID RODS, AND A FOLLOWER CARRIED BY ONE OF SAID PAIRS OF RODS, SAID ONE PAIR OF RODS BEING ROTATED CONTINUOUSLY IN OPPOSITE DIRECTIONS, AND MEANS FORMING A FRICTION DRIVE CONNECTION BETWEEN SAID FOLLOWER AND ITS SUPPORTING RODS FOR MOVING THE FOLLOWER THEREALONG AT A RATE PROPORTIONAL TO THE ROTATIONAL SPEED OF THE RODS WHEN THE FOLLOWER IS NOT OTHERWISE RESTRAINED, SAID FRICTION DRIVE PERMITTING THE FOLLOWER TO BE PULLED BACK FROM THE STACK OF BLANKS AND ITS RATE OF MOVEMENT BEING SUFFICIENTLY SLOW TO PERMIT THE FOLLOWER TO BE RELEASED AND A SUPPLY OF BLANKS ADDED TO THE STACK BEFORE THE FOLLOWER RETURNS TO THE STACK OF BLANKS.