US3538993A - Packaging machine - Google Patents

Description

United States Patent [45] Patented [72] Inventors Thomas C. Potter Park Forest and George H. Burt, Mokena, Illinois 770,142

May 13, 1968 Division of Ser. No. 543,958. April 20, 1966, now Pat. No. 3,398,675

Nov. 10, 1970 lnterlake Steel Corporation Chicago, Illinois a corporation of New York [2]] Appl. No. [22] Filed [73] Assignee [54] PACKAGING MACHINE 2 Claims, 13 Drawing Figs.

[52] US. Cl. 198/35 [51] Int. Cl. 865g 57/09 [50] FieldofSearch 198/19, 35;

2l4/6M; 53/252; 25/ l42F; 52/Sutherland [56] References Cited UNITED STATES PATENTS 3,180,279 4/1965 Thibault...... 198/19X 3,279,147 10/ I966 Garapolo 53/252 3,448,846 6/1969 Bardenhagen 5 3/150X Primary ExaminerEdward A. Sroka AttorneyWilliam P. Porcelli ABSTRACT: A machine for packaging loose stacks of articles. Loading stations are provided with backing plates against which the articles are stacked to impart vertical alignment of the articles in a stack. Conveyor means transports the stacks in jigs from station to station and guide means are arranged to urge the jigs away from the backing plates when moved from station to station to prevent the articles stacked on the jigs from sliding across the backing plates.

, Patented; Nov. 10; 1970 Sheet 1 of 6 *TH'FITTFI n 1 I ll I Geo geflliurt I izmaaC POZZZZ Patented Nov; 10, 1970 Patented Nov. 10, 1976 4 Sheet 5 of6 PACKAGING MACHINE This application is a division of U.S. Pat. application, Ser. No. 543,958, filed Apr. 20, 1966, issued as U.S. Pat. No. 3,398,675 on Aug. 27, 1968.

This invention relates to the art of stacking articles, such as bricks, in preparation for strapping the articles into bound unitized stacks.

With increased labor costs, great effort has been directed toward improving means for handling construction materials in order to lower these costs. Large quantities of bricks are used in construction work and much of this effort has been directed toward improving their handling. Although the invention, as described herein, has particular advantages for handling bricks, it is sufficiently versatile that it can be employed for handling of other types of identical or similar articles which are so shaped that they can be arranged into orderly stacks. I

Whereas, in previous years, it was common to handle bricks, and the like, in bulk, it has been learned that there are many disadvantages with bulk handling and they have been substantially overcome by using a unit pack of bricks stacked in abutting parallel rows and encircled with a loop of strap tensioned tightly to retain the bricks as a unit. Method and apparatus for providing such unit packs of bricks is shown and described in U.S. Pat. No. 3,003,296 issued Oct. 19, 1961, to John G. Feldkamp et al. Such a similar arrangement is also shown in 'a second U.S. Pat. No. 3,095,678 issued July 2, 1963, to G. J. Cliff et al. In this secondpatent is shown and described a stacking machine which is employed for proper arrangement of the bricks in stacks which are then shifted by movement on jigs to a strapping station on the machine. There the stacks are individually pushed off the jigs by means of an ejector mechanism; then, they move to a compacting station and finally to the strapping station where loopsof strap are applied around the individual stacks. As they pass through the strapping station, flexible corner protector straps are applied thereto and the finished unit packs of bricks are subsequently removed from the end of the strapping station.

With the apparatus of the type shown in U.S. Pat. No. 3,095,678, the applicants have observed problems when employing the jigs used for stacking. They are provided with horizontal slats as the backing means against-which the bricks are positioned as they are manually stacked therein. The slats are spaced vertically from each other to insure that all bricks of the stack being formed in a jig bear, at least in part, against at least one of the slats. This is intended to insure straight alignment of the-bricks without any overhang of any of them relative .to others in each stack. Certain difficulty has been encountered because of variations in the sizes of bricks to be stacked which do not correspond to the spacing of the slats in a jig. In such a situation, certain rows of the bricks may not have any backing support from any of the slats. They then overhang the other-bricks and align unevenly. With overhang of the bricks, they can interfere with structural portions of the machine or misalign with the ejector mechanism which pushes the stacks from the jigs toward the strapping station. Any interference in this manner can cause serious jamming and damage to the machine.

Just as the spacing of the slats in the jigs relative to the size of the bricks being stacked presents uneven brick alignment possibilities, the ejector mechanism is provided with slats which are positioned to pass between the slats on the jigs to effectuate proper brick stack ejection. If the slats on the ejector miss contact with any rows of the bricks, it is possible that a level of bricks can be left on the jig. This can have the effect of interfering with the return movement of the ejector and also cause jamming or severe damage to the machine.

Aside from the. damage possibilities, unevenly aligned bricks create further difficulties. When the stacks are forced one against the other, projecting bricks of adjacent stacks can overlap andinterlock each other to present difficulties when later trying to separate-one strapped stack from another after they are strapped.

It is an important object of this invention to provide an improved stacking arrangement for the jigs which ensures good alignment of the bricks with minimum chance of overhang of any of the bricks relative to others in a stack.

It is still another object of the invention to provide an improved ejector arrangement for ejecting the stacks of bricks from the jig toward the strapping station, such that ejection of all the bricks in a stack is ensured and with minimum chance of misaligning the bricks.

Other objects of the invention can be understood by referring to the accompanying drawings in which:

FIG. 1 shows a simplified diagrammatic top plan view of a preferred embodying of a machine employing the features of this invention;

FIG. 2 shows a stack of bricks in a strapped form as assembled by the machine of FIG. 1;

FIG. 3 shows a side elevation view, in partial section, of the stack ejection mechanism;

FIG. 4 is a side elevation of a brick stacking jig and its related support mechanism;

FIG. 4a is a sectional view along the line 4a-4a of FIG. 4;

FIG. 5 shows a sectional view along the line 5-5 of FIG. 3 and shows internal portions of the stack ejection mechanism;

FIG. 6 shows a sectional view along the line of 6-6 of FIG.

FIG. 7 shows a sectional view along the line 7-7 of FIG. 3', FIG. 8 shows a side elevation view of the stack compression station and the strapping station;

FIG. 9 shows an end view of the compression station as viewed along the line 9-9 of FIG. 8;

FIG. 10 shows a side elevation view in partial section of the portion of the compression station containing the compression fingers;

FIG. 11 is a left side elevation view of the portions of the compression station shown in FIG. 10; and

FIG. 12 shows a sectional view along the line 12-12 of FIG. 10.

The basic components of the invention as shown in FIG. 1 are the jig conveyor unit 1, the stacking jigs 2 carried by it, the stack ejector 3, the compression station 4, the strapping station 5 and the exit conveyor 6.

The jig conveyor unit I is composed of a sturdy overhead support frame 7 which is provided with a continuous loop of eye-beam-shaped rail 7a (FIGS. 1, 3, 4) which guide oppositely facing guide rollers 7b rotatably mounted on hangers 7c from which the stacking jigs 2 are suspended. This general type structure is shown in U.S. Pat. No. 3,095,678, issued July 2, 1963 to G. J. Cliff et al.; herein previously referred to. There are two of these hangers 7c for each jig and a continuous chain.7d is connected to these hangers in a continuous loop following the looped shape of the frame 7. As the chain 7 is driven by suitable power means, these stacking jigs 2 follow the path of the loop of the frame 1 with intermittent motion so that successive loaded stacking jigs 2 align between the stack ejector 3 and the compression station 4. This intermittent motion also aligns successive stacking jigs 2 with certain backing plates 8 rigidly mounted adjacent certain of the loading regions of the frame 7. A suitable power means for this intermittent motion is shown in said U.S. Pat. No. 3,095,678.

By employing this intermittent motion, the individual stacking jigs 2, as they follow their looped path, stop in front of the backing plates 8 where they are loaded with bricks. The backing plates 8 insure that the bricks stack evenly on the stacking jigs with no overhang of any of the bricks relative to others in each stack. After they pass these backing plate stations, the stacking jigs 2 intermittently stop, as mentioned, between the stack ejector 3 and the compression station 4. The stack ejector 3 then causes the stack of bricks on the stacking jig positioned between the stack ejector 3 and the compression station 4 to be ejected from its stacking jig 2 and moved to the compression station 4. The stack ejector is employed to -both eject the stack and to compress the ejected stack against other leading stacks which have been previously ejected. This causes them to be pressed tightly against each other and moved forward along the compression station 4 and finally to the strapping station 5 where straps are encircled and secured around the stacks.

In more detail, each stacking jig 2, when it reaches a backing plate 8. as shown in FIG. 4, swings toward the backing plate 8 by gravity. This is accomplished by means of rollers 9 projecting from the bottom of each stacking jig 2 which are guided along a lower rail 10 (FIGS. 4 and 4a). This movement by gravity occurs by having the stacking jigs ordinarily sloped at a slight angle as they ordinarily are guided along the lower rail 10 which is provided with two detents 11 into which the rollers 9 drop as a stacking jig 2 arrives at a station in alignment with a backing plate 8. This guarantees that each stacking jig 2 hears its full back area flush against a backing plate 8. In this manner, when the bricks B are stacked in the stacking jig 2, they all align evenly with the surface of a backing plate 8. In order to insure that the bricks B will not scrape unnecessarily against a backing plate 8 when a loaded stacking jig moves away from a backing plate during the intermittent motion of the conveyor unit I, the rollers 9 roll up the detents 11 and cam the stacking jig away from the backing plate 8. Even though the trailing roller of the two rollers 9 ofa single stacking jig will pass by the leading detent II as a stacking jig moves, the leading roller 9 bearing along the straight portion of the lower rail 10 will prevent it from dropping into the leading detent 11. These backing plates 8 are provided at as many stacking stations of the jigs as conveniently possible along the entire path of the loop of the conveyor unit 1. This enables workers to be stationed around the conveyor unit loop and participate in the loading of all of the stacking jigs 2 by having workers place a certain number of bricks in each of the stacking jigs 2. By the time the last stacking station is reached, a stacking jig will be full.

The stack ejector 3, as shown in FIGS. 1,3,6 and 7 consists of a skeletal box-shaped frame 11a provided with two inverted, V-shaped rails I2 and 13 along which are guided four wheels l4. These wheels 14 are journaled on shafts 14a secured to a cylinder support frame 15. The frame 11a is provided with a transverse support 16 having two vertically extending pivot plates 17 on which the leading end 18a ofa fluid cylinder 18 is pivoted by means of pivot pins 18b. The rear end 18c of the cylinder 18 is unsupported.

The cylinder 18 houses a piston 19 connected to a piston rod 19a. The leading end 19!) of the piston rod 190 is journaled by a pin 20 to a connector 21 joined to a front wall 150 of the cylinder support frame 15. This wall is provided with four horizontal extending rails 22 which extend well beyond the front wall 15a. At the far ends of these rails 22 is a flat plate 23 which provides the surface for reacting against the bricks to eject them from a stacking jig 2. Adjacent to the flat plate 23 is an auxiliary plate 230 which is removably mounted to the supporting structure for the flat plate 23 which functions as an extension of the flat plate 23 to accommodate brick stacks of different widths and it can be of any suitable width depending upon the width of the particular brick stack to be ejected. It can be bolted to the supporting structure or provided with a common quick release mechanism.

In order to provide stacks of bricks B of different widths, each stacking jig 2 is provided with a movable wall 2a (FIG. 4) which is secured to the base 2b and an upper support 2c of each stacking jig 2 by means of bolts 2d. A multiple number of holes are provided along each of the members 2b and 2c so that the wall can be positioned at different width spacings from the opposite wall 2e ofthe stackingjig 2.

When the stack ejector 3 causes a stack of bricks B to be ejected from a stacking jig 2 and into the compression station 4, the stacks of bricks ahead of the particular stack being ejected are urged through the compression station 4. This compression station 4 is similar in many respects to the compression station in said U.S. Pat. No. 3,095,678 except that it embodies improvements over what is there shown.

The construction of the compression station 4 is particularly shown in FIGS. 8-12 where it is supported by a hollow structural frame 24. This frame 24 has two overhead horizontal rails 25 on which four grooved rollers 26 are guided for movement transversely of the frame 24. These four rollers 26 are supportedon shafts 27 which are journaled to the upper end of a spring finger support frame 28. Mounted to guide along the lower surfaces of plates mounted below the guide rails 25 are additional rollers 29 which, together with the rollers 26, keep the frame 28 from vertical movement. This frame 28 has supporting structure 28a on its forward face which supports a plurality of fingers 30. Each of these fingers is pivoted on a shaft 31 to the supporting structure 28a and each is biased by a spring 32 connected between an end 30a of each finger 30 and an adjustable shaft 32a. At the free ends ofeach ofthe fingers 30 are journaled rollers 33 and the bias of the springs 32 urges the fingers 30 in a direction to move the rollers 33 into the path of a stack of bricks passing through the compression station 4. The spring finger support frame 28 is provided at its rear surface with a pivot 34 connected to the leading end 35 of a piston rod 36 connected to a piston 37 in a cylinder 38. Suitable fluid pressure applied to the piston 37 urges the support frame 28 and the rollers 33 on the fingers 30 in a direction toward the sides of stacks of bricks passing through the compression station 4. The rolling action of the rollers 26 and 29 permits the spring finger support frame 28 to be shifted toward the brick stacks by the force of the piston 37.

Opposite the position of the spring fingers 30 on the support frame 28 is a wall of rollers 39 journaled along the upper half of the area. These rollers 39 and the rollers 33 allow movement of the brick stacks through the compression station 4 without any scraping action.

The principal purpose of these spring fingers 30 is to assist in compacting the stacks of bricks so that all of the bricks in a stack are compressed tightly toward each other transversely. They also provide a degree of drag of a stack as it passes through the compression station 4 and this causes the stacks to be drawn together tightly longitudinally of the movement of the stacks through the compression station 4, the rollers 33 preventing the fingers 30 from dragging along the sides of the stacks and scraping the bricks. Also, at the separation between one row of bricks and another, if there is any step, the fingers snap down or up over the step and, without the rollers, would damage the bricks. The rollers provide a rolling action without any harmful quick snapping action of the fingers 30.

Whereas, on prior devices, proper adjustment of the finger pressure was required for each individual finger and, if the stack was too narrow, the fingers might not touch it at all. By the improved device of this invention, the support frame 28 is movable by means of the force of the piston 37 so that the rollers 33 can be urged against all brick stacks, regardless of width. Further, uniform pressures can be applied by means of the piston 37, even though there has been no change in the adjustment of the individual springs 32 biasing the fingers 30. Also, it is possible to preset the operating fluid pressure of the cylinder 38 in advance to provide the desired pressure of the rollers 33 against the brick stacks, and the pressure against the individual stacks will be the same regardless of stack width. The device compensates for stack width by more or less travel of the support frame 28. In fact, once set, it is unlikely that any further adjustment of the springs 32 will be required.

As the stacks pass through the compression station, they are fed with corner protector strips C at the four corners of the stacks by applying means clearly shown in said US. Pat. Nos. 3,095,678 and 3,003,296. Further, as each of the stacks reaches the strapping station 5, an automatic strapping machine 40 can apply a strap loop 41 around each of the stacks, or suitable strapping equipment as indicated in said patents can be employed, all of which strapping equipment is well known and available for purchase. A typical strapped stack of bricks B is indicated in Fig. 2 with an encircling strap 42 around it. The corner protector strips C are applied continuously and link one stack of bricks B with the stacks behind it. As a sufficient number of linked stacks is obtained, the corner protector strips C are severed by suitable means to separate a unit of four'or five or more or less stacks from the remaining stacks and such a group of stacks 42 is then shifted to the exit conveyor 6 where it is removed for shipment or storage.

As shown in FlGS.- 9, l0 and 12, the leading row of fingers 30 at the compression station 4 have rollers 33 which extend forward of the strap guide 100 so that rollers 33 are positioned to bear against the bricks of a stack on both sides of the region of a stack where an encircling binder strap is to'be applied when the stack is in the strapping station 5. This insures that the bricks of a stack are compacted laterally and held in their compacted positions until after an encircling binder strap is applied. With prior devices, all compacting was achieved ahead of the strapping station with the result that the bricks would tend to fan open as they would leave the compression station and enter the strapping station. By having the compression means extending far enough, as described, this fanning out of the bricks is eliminated and tight and orderly packages of bricks or other objects can be obtained.

' 'lhe cylinders l8 and 38 can be provided with tluid for actuation from a suitable power source, not shown, which can be automatically sequenced to operate in timed relationship with the intermittent motion of the conveyor unit 1, or else provided with suitable manual controls for manuallyoperating these devices when necessary. it should also be mentioned that the compression station 4, the strapping station 5, and the exit conveyor 6 are all provided with freely joumaled support rollers 43 which allow the brick stacks to freely roll through these stations. Also, adjacent the exit conveyor 6 can be mounted another cylinder 44 having a piston rod 45 connected to an Lshaped frame 46 for ejecting the brick stacks.

'It should be evident that the major advantages of this invention relates to the improved stacking arrangement involving the backing plates 8 as simple means for insuring that the bricks are stacked along an even facing without any of the bricks projecting or overhanging others. Further, the stack ejector 3 has a flat plate which bears against anentire area of the brick stack to insure that the bricks remain in their straight alignment during ejecting. In addition, this improved stacking and ejecting means insures minimum damage to the bricks. Also, the improved spring finger arrangement guarantees good eompat'ting ol' the bricks and the stacks of bricks with minimum damage to the bricks and with minimum, if any, need for adjustmentwhen the brick stackwidths vary.

We claim: v i

l. A machine for packaging articles comprising, a jig for receiving and supporting a plurality of articles in a given loose- 7 ly stacked arrangement, conveyor means for conveying said jig along an endless path past a number of loading stations at each of which a desired number of articles are placed thereon to progressively build a complete stack, the jig being open at its front face to permit the articles to be positioned thereon, said jig being open at its rear face, each loading station being provided with a backing plate of at least the area of the opening at the rear face of the jig which covers said opening when the jig is at the loading station, said backing plate providing a planar back support against which the articles are stacked in the jig to facilitate vertical alignment of the articles in a stack, the jig being suspended from the conveyor means with allowable pendulum type angular movement relative to a backing plate, a guide rail on the conveyor means substantially following the path of the conveyor means toward which rail the jig is urged by gravity, said guide rail being provided with at least one detent corresponding to the location of a backing plate,

into which detent a portion of the jig moves by the action of gravity as the jig reaches the location of the backing plate to thereby move the jig into contact against the backing plate, further movement of the conveyor means and resultant movement of the jig from .the locationof the backing causing said portion of the jig to move out of engagement with the detent and urge the jig an nularly away from the backing plate to thereby relieve he ig an the articles stacked thereon from sliding across the backing plate as the jig moves to the location of the next loading station.

2. A machine for packaging articles comprising, a jig for receiving and supporting a plurality of articles in a given loosely stacked arrangement, conveyor means for conveying said jig along an endless path past a number of loading stations at each of which a desired number of articles are placed thereon to progressively build a complete stack, the jig being open at its front face to permit the articles to be positioned thereon,

'said jig being open at its rear face, each loading station being provided with a backing plate of at least the area of the open ing at the rear face of the jig which covers said opening when the jig is at the loading station, said backing plate providing a planar back support against which the articles are stacked while they are stacked in the jig to facilitate vertical alignment of the articles in a stack, the jig being connected to the conveyor means with allowable movement toward and away from a backing plate guide means on the conveyor means substantially following the path of the conveyor and engaged with the jigto guide it from loading station to loading station, the guide means being provided with an offset at a loading station which urges the jig against the hacking plate at the loading station in readiness for loading, the offset urging the jig away from the backing plate when the conveyor means moves the jig past the loading station to thereby relieve the jig and the articles stacked thereon from sliding across the backing plate as the jig moves to the location of the next loading station.

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