US3602107A

US3602107A - Carton flap folder

Info

Publication number: US3602107A
Application number: US835035A
Authority: US
Inventors: Richard C Zimmer; Robert F Lense
Original assignee: Riegel Paper Corp
Current assignee: Riegel Paper Corp
Priority date: 1969-06-20
Filing date: 1969-06-20
Publication date: 1971-08-31
Anticipated expiration: 1988-08-31
Also published as: SE341593B; GB1290756A; DE2030202A1

Abstract

A machine for folding the leading and trailing flaps of cartons being advanced one by one by a chain along a predetermined path. The leading flaps are folded by a wheel with a number of retarders spaced about the periphery of the wheel. The wheel turns to bring a retarder into intersecting relation with the path of each carton ahead of the leading flap. When in intersecting relation with the path, the retarder moves in the flow direction of the cartons but at a slower speed. The leading flap thus catches up with the retarder and is engaged by the latter. Due to the difference in speed, the carton passes by the retarder, and the leading flap is folded. The wheel is rotated in timed relation with the advance of the cartons by a drive directly connected to the drive for a cutter rotor which is rotated in timed relation with the advance of the cartons. The trailing flaps of the cartons are folded by a folding rotor which is driven in timed relation with the advance of the cartons by the same drive chain which advances the cartons.

Description

United States Patent [72] lnventors RichardC.Zimmer;

Robert F. Lense, both of Rockford, Ill.

[21] Appl. No. 835,035

[22] Filed June 20,1969

[45] Patented Aug. 31, 1971 [73] Assignee Riegel Paper Corporation New York, N.Y.

[54] CARTON FLAP FOLDER {1113,6UJU7 Primary Examiner-Travis S. McGehee Attorney-Wolfe, Hubbard, Leydig, Voiit & Osann ABSTRACT: A machine for folding the leading and trailing flaps of cartons being advanced one by one by a chain along a predetermined path. The leading flaps are folded by a wheel with a number of retarders spaced about the periphery of the wheel. The wheel turns to bring a retarder into intersecting relation with the path of each carton ahead of the leading flap. When in intersecting relation with the path, the retarder moves in the flow direction of the cartons but at a slower speed. The leading flap thuscatches up with the retarder and is engaged by the latter. Due to the difference in speed, the carton passes by the retarder, and the leading flap is folded. The wheel is rotated in timed relation with the advance of the cartons by a drive directly connected to the drive for a cutter rotor which is rotated in timed relation with the advance of the cartons. The trailing flaps of the cartons are folded by a folding rotor which is driven in timed relation with the advance of the cartons by the same drive chain which advances the cartons.

PATENIEU was] 197i 39602.10?

sum 1 BF 3 CARTON IFILAIP FOLDER BACKGROUND OF THE INVENTION This invention relates to a machine for folding flaps on cartons from extended positions to folded positions as the cartons are advanced rapidly along a predetermined path.

SUMMARY OF THE INVENTION The primary object of the present invention is to fold the leading flaps of the rapidly advancing cartons gently at a relative rate of speed much slower than the advancement speed of the cartons to insure that all of the flaps are folded but not torn or bent out of shape.

It is a related object of the present invention to fold the leading flap of each carton gently by retarding the forward motion of the flap with respect to the carton such that, while both are moving forwardly along the path, the carton moves faster than the flap, and the flap is folded rearwardly.

It is a further object to accomplish the above by mounting a wheel with retarders spaced angularly around the periphery thereof to rotate and project the retarders, one at a time, into intersecting relation with the path of successive cartons ahead of the leading flap of each carton. The retarder in intersecting relation with the path moves in the same direction as the respective carton but at a slower speed causing the leading flap of the carton to catch up with and be engaged by the retarder to fold the leading flap rearwardly during the advance of the carton.

It is a more detailed object to form each retarder as a radially extending finger bent around to form a pocket which opens in the upstream direction of the path when the retarder is in intersecting relation with the path so that the finger engages the leading flap and guides the flap into and then out of the pocket thus folding the flap as the carton advances.

It is another object to drive the wheel carrying the retarders in timed relation with the advance of the cartons by a direct power takeoff from the drive of a cutter positioned upstream of the wheel and used to separate the cartons as the latter are advanced along the path.

It is an object to use a chain drive both to advance the car tons and to drive a folding rotor in timed relation with the advance of the cartons to fold the trailing flaps of the cartons.

Other objects and advantages will become apparent from the following detailed description taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF TI-IE DRAWINGS FIG. I is a fragmentary elevation of a machine embodying the novel features of the present invention.

FIG. 2 is a fragmentary plan view taken substantially along the line 2-2 of FIG. 1.

FIG. 3 is a fragmentary elevation similar to FIG. I but with framework removed for clarity and with parts shown in moved positions.

FIG. 4 is a fragmentary elevation similar to FIG. 3 but with the parts shown in still further moved positions.

FIG. 5 is a fragmentary elevation of the machine of FIG. I and showing the folding of both the leading and trailing flaps ofa series ofcartons.

FIG. 6 is a fragmentary cross section of a portion of the machine shown in FIG. 5 and taken substantially along line 6 of FIG. 7.

FIG. 7 is a partial cross section taken substantially along line 7-7 of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in the drawings for purposes of illustration, the invention is embodied in an automatic flap-folding machine operable to fold the lower hinged leading flaps 10 (FIG. 1) and trailing flaps ll of cartons 12 as the cartons are advanced continuously at a high rate of speed along a predetermined path. During their advance, the cartons are held in an upright position by carton holders 13, the latter being attached to and carried by a drive chain 14. The cartons are of the type having hinges with a resilient memory normally causing the flaps to assume upright positions protecting downwardly from the cartons.

In this instance, a continuous sealing strip 115 (FIG. 4) is heat sealed to the open bottoms of the cartons 12 and across the leading flaps 10 and trailing flaps 11 of each carton. To separate the cartons, the sealing strip is cut between the trailing flap of one carton and the leadlin g flap of the following carton. A cutter wheel or cutter rotor 17 (FIG. 1) is mounted on an axle 18 (FIG. 2) to rotate about an axis extending laterally of and below the path of advancement of the cartons. The cutter rotor is formed with four arms 19 (FIG. 3) extending radially outwardly from the axle and spaced angularly apart. Connected to the end of each arm is a cutter or cutting blade 20 which extends laterally of the path of carton advancement. The cutter rotor is positioned below the path a distance such that the blades can be rotated into intersecting relation with the path.

As the cartons 12 advance, the cutter rotor 17 rotates counterclockwise (FIG. 1) in timed relation to the advance of the cartons such'that one of the blades 20 rotates up and into the space between adjacent cartons thereby cutting the sealing strip 15 and separating the cartons. That is, the rotor is driven with a peripheral speed equal to the advancement speed of the cartons and thus successive blades move between successive cartons and cut the sealing strip as the rotor turns. This sequence is shown in progressive steps in FIGS. 1, 3 and 4.

The axle 18 is journaled at one of its ends in a support plate 21 (FIG. 2), and the other end of the axle is journaled in a gearbox 22. Through a series of gears within the gearbox, the axle is connected to and driven by a drive shaft 241 (FIG. 1) which extends from and is supported by a frame member (not shown) and the gearbox is pivoted on the drive shaft for swinging back and forth through a limited range about the latter. To prevent the cutter rotor 17 from damaging a great number of cartons 12 should the rotor jam, the rotor is adapted to be moved automatically out of intersecting relation with the path if one of the holders l3 presses against a blade 20 of the rotor. For this purpose, a pair of parallel rods 25 and 26 (FIG. 2) extend between and are fastened rigidly to the support plate 21 and the gearbox 22 to join the gearbox and the support plate as a single unit for swinging movement together about the drive shaft 24. This unit is urged in a clockwise direction about the drive shaft by a spring-biased rod 28 (FIGS. 1 and 2) which is pivotally connected at one end portion to the support plate 211 at a level below the axis of the drive shaft. As most clearly shown in FIG. 1, a spring 29 is telescoped over the other end portion of the rod 28 and is biased between a nut 30 on the end of the rod and an L-shaped plate 31 through one leg of which the rod extends slidably, the other leg of the plate being bolted to a stationary frame member 32. If the rotor should jam, the force of the cartons 12 being moved along the path will swing the unit counterclockwise about the drive shaft against the force of the spring thereby to free the blades from the cartons. To hold the unit against clockwise swinging which would result due to the spring, a screw 35 (FIG. ll) threaded into a plate 36 on the frame member 32 contacts the rod 26 and may be adjusted to change the normal position of the unit.

When the sealing strip 15 is sealed to the cartons 12, the leading and trailing

flaps

10 and 11 are pressed upwardly to horizontally extending positions and project forwardly and rearwardly, respectively, from the cartons. Once the sealing strip has been cut, the flaps are free to spring downwardly toward their normal upright positions as a result of the resilient memory of the flap hinges. Due to a number of factors, however, the flaps may remain in nearly horizontal positions thus making it difficult to engage and fold the flaps to closed positions over the bottoms of the cartons. For example, the memory of the flap hinges usually is weakened when uping strip. In addition, the strip itself underlies the flaps and tends to resist downward swinging of the latter. Any sticky product which may have accumulated around the flaps also may tend to keep the flaps in generally horizontal positions. The flaps thus may remain positioned closely adjacent the holders l3 and, when the cartons are being advanced at high speeds, difliculties are encountered in folding the flaps to closed positions without tearing or distorting the flaps.

In accordance with the present invention, the advancement of the leading flap of each carton 12 is retarded smoothly and gradually in a manner which allows the leading flap to advance along the path but at a slower speed than the carton, and the leading flap is folded by being guided downwardly from a forwardly extending horizontal position, through a vertical position, and then rearwardly toward a rearwardly extending horizontal position as the carton moves past the flap due to the difference in advancement speed between the carton and the flap. For these purposes, a wheel 40 (FIG. 1) with a number of retarders 41, herein four, on the periphery thereof is mounted to rotate about an axis extending laterally of and below the advancement path of the cartons such that the retarders are rotated counterclockwise (FIG. 1) one at a time into the path just ahead of the leading flap of an advancing carton. The wheel is rotated with a peripheral speed less than the advancement speed of the carton so that the leading flap catches up with and is engaged by the retarder which shows the advancement of the flap while guiding the latter first downwardly and then upwardly toward a folded position. With this arrangement, each leading flap is engaged and folded slowly while the carton is being advanced at a high speed resulting in a gently folding action and the substantial elimination of tearing, ripping, etc. which normally occurs if the flap is engaged by a stationary flap folder.

Extending upwardly at an angle in a downstream direction and attached to thesupport plate 21 by a pair of bolts (FIG. 1) is a support frame 43 (FIG. 2) in which a drive shaft 45 is journaled, and the wheel 40 is rigid with one end portion of the drive shaft to rotate with the latter. The wheel is advantageously driven directly from the axle 18 of the cutter rotor 17 at the same angular speed as the rotor. To accomplish this, a chain 46 (FIG. 2) is trained around a first sprocket 47 mounted on the axle and a second sprocket 48 mounted on the end portion of the drive shaft 45 opposite the end portion on which the wheel 40 is mounted. As shown in FIG. I, the drive shaft 45 is located above the axle l8 and thus nearer the path of advancement. Since the distance to the carton path is shorter, the diameter of the wheel is less than that of the cutter rotor causing the wheel, which is rotated at the same angular speed as the rotor, to rotate with a slower peripheral speed than the rotor. Since the peripheral speed of the rotor is equal to the advancement speed of the cartons, the peripheral speed of the wheel is less than the advancement speed of the cartons.

Each retarder 41 in this instance is formed as a finger 49 (FIG. I) curved around to form a mouth or pocket 50 which when the retarder is positioned in intersecting relation with the path, opens in an upstream direction. One retarder is rotated into intersecting relation with the path of the cartons 12 just ahead of each leading flap 10. As the leading flap in its extended position advances along the path at the advancement speed of the carton, the leading flap catches up with the retarder which is being rotated counterclockwise (FIG. 1) or away from the leading flap. Because the leading flap extends downwardly slightly below horizontal, the trailing edge of the finger 49 can engage the upper side of the flap and can guide the flap into the pocket 50. The thickness of the trailing edge portion of the finger is relatively small and, when the finger engages the leading flap, the trailing edge of the finger is just barely below the bottom 51 (FIG. 1) of the body of the carton to engage and draw the flap downwardly. One particular advantage to this arrangement is that while the downward angle that the leading flap makes with the horizontal may be very small, as for the reasons mentioned above, the finger will still engage the upper surface of the flap ensuring that no leading flap remains in an extended position. By observing the sequence of operation as depicted in FIGS. 1, 3 and 4, it will be seen that, as the carton 12 catches up with and then passes the retarder 41, the leading flap 10 is guided downwardly into the pocket 50 and then slides along the finger and is bent upwardly and rearwardly toward a folded or closed position by the finger as the carton passes over the retarder.

Advantage is taken of the provision of the drive chain 14 to use the latter additionally to fold the trailing flaps 11 by driving a folding rotor 53 (FIG. 6) in timed relation with the advance of the cartons 12. As shown in FIG. 7, the folding rotor turns about a vertical axis a positioned laterally of the advancement path of the cartons. A bearing housing 54 is fixed to the end of a cantilevered arm 55 which extends horizontally from the frame 32. Within the bearing housing is a bearing 56 in which a shaft 57 is journaled to rotate about the axis a, and a washer 58 is welded around the shaft near the upper end of the shaft to prevent the latter from falling through the bearing. Beneath the housing 54, a sprocket 60 with a downwardly extending hub 61 is telescoped on and connected to the lower end portion of the shaft by a splined connection. .Iournaled on the shaft beneath the hub is a disc 62 and, beneath the disc, a retainer plate 63 abuts the end of the shaft. A screw 64 extends through the retainer plate and intothe end of the shaft to hold the plate, hub, and disc on the shaft. Three screws 65 (two shown in FIG. 7) extend upwardly through and lock the retainer plate, the disc and into the hub together thus causing the disc to rotate with the hub and sprocket.

Onthe periphery of the sprocket 60 is a series of teeth 66 (FIG. 6) which engage the drive chain 14 causing the sprocket to be rotated with a peripheral speed equal to the advancement speed of the cartons 12. Four radially extending folding blades 67 are angularly spaced at intervals about the periphery of the disc 62 and, as the disc turns in response to rotation of the sprocket by the drive chain, these blades are swung one at a time into intersecting relation with the path of the advancing cartons. With the folding rotor 53 located laterally of the path on the same side of the path as the drive chain, the distance from the shaft 57 to the path is greater than the distance from the shaft to the drive chain.

With the above arrangement, the folding blades 67 move with a greater speed than the advancement speed of the cartons 12 causing each blade to overtake the carton immediately ahead of that blade when the latter enters the path. The folding blade thus catches up with, engages, and folds the trailing flap ll forwardly as the blade moves through the path, and this is accomplished gently because. the differential in the speed of the folding blade and the carton is relatively small. To ensure that each blade enters the path just behind a carton, the angular position of the disc 62 can be adjusted with respect to the sprocket 60. A series of arcuate slots 68 (FIG. 6) are formed in the disc at the location for each screw 65. Before the screws are tightened to join the retainer plate 64, the disc 62, and the sprocket 60, the disc can be shifted angularly with respect to the sprocket to the extent of the slots.

This arrangement can be varied somewhat but, as shown here, the folding rotor 53 is located immediately downstream of the wheel 40. Just downstream of the folding rotor is a plow 70 (FIG. 5) which forces the folded leading flaps l0 and trailing flaps ll tightly up against the bottoms 51 of the cartons 12.

From the above, it will be observed that the provision of the wheel 40 moving the retarders 41 one at a time into intersecting relation with the path of the advancing cartons 12 with the retarders moving in the same direction as the cartons when the retarders are in the path but at a slower speed to retard the leading flaps 10 and fold the latter is a particularly advantageous arrangement. This arrangement makes it possible to fold the leading flaps gently at a differential speed much less than the advancement speed of the cartons. For easy power transmission and simple, effective timing of the rotation of-the wheel, the latter is driven directly off the drive for the cutter rotor 17. Another advantageous arrangement is the utilization of the drive chain 14 not only to advance the cartons but also to rotate the folding rotor 53 in timed relation to the advance of the cartons to fold the trailing flaps 11.

We claim as our invention: V

1. In a machine for rearwardly folding the hinged leading flap of a carton from an extended position to a folded position as the carton is advanced along a preselected path with the flap projecting from the carton and disposed in said extended position, the combination of, a support, mechanism on said support for advancing the carton at a predetermined speed along said path, a wheel journaled on said support to turn about an axis spaced from and extending transversely of said path, a retarder on the periphery of said wheel and rotatable into intersecting relation with said path and ahead of the leading flap as an incident to rotation of the wheel, and means for rotating said wheel to move the retarder in the same general direction as the leading flap when the retarder is disposed ahead of the flap but at a speed less than the speed of the carton whereby the leading flap catches up with and is engaged by the retarder and is gradually folded rearwardly during advancement of the carton along said path, said retarder being a finger curved around to form a pocket which opens in a direction upstream of said path when said retarder is disposed in intersecting relation with said path so that said finger can engage said leading flap and guide the latter into said pocket to fold the flap as the carton advances along said path past retarder.

2. The machine of claim 11 in' which said mechanism for advancing the carton includes a power-driven carrier chain, said machine further including means for folding the hinged trailing flap of said carton from an extended position in which the flap projects from the carton to a folded position as the carton is advanced along said path, said last-mentioned means comprising a folding rotor mounted to turn about an axis perpen dicular to but laterally offset from said path, a folding blade on said rotor and extending radially outwardly therefrom, said carrier chain being operably connected to said folding rotor to rotate the latter and move said blade into intersecting relation with said path in timed relation with the advance of said carton to engage said trailing flap and fold the latter from said extended position to said folded position.

3. The device of claim 2 in which said drive chain is positioned laterally of said path, said axis of said folding rotor being positioned on the same side of said path as said chain, said folding rotor including a sprocket mounted to rotate about said axis and drivingly engaged by said chain to rotate said sprocket with a peripheral speed substantially equal to the advancement speed of said carton and to cause said blade to move with a speed greater than the advancement speed of said carton whereby said blade is operable to enter said path behind said trailing flap and overtake said trailing flap to fold the latter.

4. In a machine for rearwardly folding the hinged leading flaps of a series of connected cartons from extended positions to folded positions as the cartons are advanced one by one along a preselected path at a predetermined speed with the flaps projecting from the cartons and disposed in said extended positions, the combination of, a support, a rotor journaled on'said support to turn about an axis spaced from and extending transversely of said path, cutters on the periphery of said rotor and rotatable with the latter into intersecting relation with the path for separating the cartons from one another, a drive mechanism connected to said rotor to rotate said cutters with a peripheral speed substantially equal to said predetermined speed, a wheel journaled on said support downstream of said rotor to turn about an axis spaced from and extending transversely of said path, retarders spaced angularly about the periphery of said wheel and rotatable with the wheel into intersecting relation with said path, drive means connected between said drive mechanism and said wheel to rotate said wheel in timed relation with said rotor to move each retarder ahead of one of the leadin fla s in timed relatlon with the advance of the cartons an in t e same general direction as the leading flap when that retarder is disposed ahead of the flap, and said drive means being operable to rotate said wheel with a peripheral speed less than the speed of said cartons whereby the leading flap of each carton catches up with and is engaged by one of the retarders and is folded rearwardly as such carton is advanced along said path.

5. In a machine for rearwardly folding the hinged leading flaps of successive cartons from extended positions to folded positions as the cartons are advanced in spaced relation along a preselected path with the flaps projecting from the cartons and disposed in said extended positions, the combination of, a support, mechanism on said support for advancing the cartons at a predetermined speed along said path, a folding wheel journaled on said support to turn about an axis spaced from and extending transversely of said path, a series of angularly spaced fingers and intervening pockets formed around the periphery of said wheel, said fingers being rotatable into intersecting relation with said path and ahead of the leading flaps of successive cartons as an incident to rotation of said wheel, each of said pockets opening out of the peripheral surface of said wheel and receiving one of said flaps when the finger ahead of the pocket is positioned ahead of such flap, and means for rotating said wheel to move each finger in the same general direction as the respective flap when the retarder is disposed ahead of such flap but at a speed less than the carton whereby the flap catches up with and is engaged by the finger and is gradually folded rearwardly during advancement of the carton along said path.

a. In a machine for folding the hinged flaps of successive cartons as the cartons are advanced in spaced relation along a predetermined path, the combination of, a support, a powerdriven chain on said support for advancing said cartons along said path, a folding rotor mounted to turn about an axis perpendicular to but offset from said path, angularly spaced folding blades on said rotor and extending radially outwardly therefrom, a sprocket fastened to and coaxial with said rotor and having its periphery located radially inwardly of the free ends of said blades, and said chain extending tangentially of and meshing with said sprocket to rotate said rotor and move said blades into intersecting relation with said path in timed relation with the advance of the cartons whereby said blades engage and fold said flaps.

Claims

2. The machine of claim 1 in which said mechanIsm for advancing the carton includes a power-driven carrier chain, said machine further including means for folding the hinged trailing flap of said carton from an extended position in which the flap projects from the carton to a folded position as the carton is advanced along said path, said last-mentioned means comprising a folding rotor mounted to turn about an axis perpendicular to but laterally offset from said path, a folding blade on said rotor and extending radially outwardly therefrom, said carrier chain being operably connected to said folding rotor to rotate the latter and move said blade into intersecting relation with said path in timed relation with the advance of said carton to engage said trailing flap and fold the latter from said extended position to said folded position.

4. In a machine for rearwardly folding the hinged leading flaps of a series of connected cartons from extended positions to folded positions as the cartons are advanced one by one along a preselected path at a predetermined speed with the flaps projecting from the cartons and disposed in said extended positions, the combination of, a support, a rotor journaled on said support to turn about an axis spaced from and extending transversely of said path, cutters on the periphery of said rotor and rotatable with the latter into intersecting relation with the path for separating the cartons from one another, a drive mechanism connected to said rotor to rotate said cutters with a peripheral speed substantially equal to said predetermined speed, a wheel journaled on said support downstream of said rotor to turn about an axis spaced from and extending transversely of said path, retarders spaced angularly about the periphery of said wheel and rotatable with the wheel into intersecting relation with said path, drive means connected between said drive mechanism and said wheel to rotate said wheel in timed relation with said rotor to move each retarder ahead of one of the leading flaps in timed relation with the advance of the cartons and in the same general direction as the leading flap when that retarder is disposed ahead of the flap, and said drive means being operable to rotate said wheel with a peripheral speed less than the speed of said cartons whereby the leading flap of each carton catches up with and is engaged by one of the retarders and is folded rearwardly as such carton is advanced along said path.

6. In a machine for folding the hinged flaps of successive cartons as the cartons are advanced in spaced relation along a predetermined path, the combination of, a support, a power-driven chain on said support for advancing said cartons along said path, a folding rotor mounted to turn about an axis perpendicular to but offset from said path, angularly spaced folding blades on said rotor and extending radially outwardly therefrom, a sprocket fastened to and coaxial with said rotor and having its periphery located radially inwardly of the free ends of said blades, and said chain extending tangentially of and meshing with said sprocket to rotate said rotor and move said blades into intersecting relation with said path in timed relation with the advance of the cartons whereby said blades engage and fold said flaps.