US2732995A - Packing case - Google Patents

Description

PACKING CASE Filed Sept. 12, 1949 JNVENToRs WML/AM GE/SLER mme/5mm@ TTURNEYS United States Patent O PACKING CASE William Geisler, Tenally, N. J., and Woolridge B. Morton, New York, N. Y., assignors, by mesne assignments, to Wilbro Corporation, Hackensack, N. J., a corporation of New Jersey Application September 12, 1949, Serial N o. 115,309

1 Claim. (Cl. 229-33) This invention relates to packing cases and method of making the same, and has for its object to provide a packing case made of liber board, corrugated board or the like, which is stiiiened at certain portions, particularly the vertical corners, to so reinforce the carton that it will retain its shape under normal stacking loads and during the handling incidental to shipment to a considerably greater extent than cases made of the same weight of board but without the stiffened sections.

A further object of the invention is to provide a carton of this class wherein the stiifening of the corners and other sections is accomplished with very small addition to the cost of manufacture. By stiffening the carton in the manner described a lighter weight of board may be used for the same load than required when the board is unstiiened and the saving in board cost is several times greater than the added cost of manufacture of the stiifened carton.

A further object of the invention is to provide a case wherein the amount of board required for a case of a given size is considerably less than that required for the ordinary packing case comprising the four side walls with overlapping iiaps at each end.

A further object of the invention is to provide a case of the kind described which may be readily erected from a at blank and may then belled and closed by means of the ordinary case-packing and closing machines which are commonly used in connection with the conventional paper packing cases having overlapping top and bottom aps.

In the accompanying drawings there is shown a pre ferred form of the improved case suitable for use wherever a packing case of the conventional type is now employed. There is also shown a modified form of the improved case especially designed for beer bottles and the like.

In the accompanying drawings:

Fig. l shows in plan the cut and scored blank from which my improved case is formed at an intermediate stage in the making of the case;

Fig. 2 is a sectional detail view showing the method of forming the stiffened corners;

Fig. 3 is a detail view of a section of the flat blanks with the stitfened corners nested together for shipment;

Fig. 4 is a perspective view showing the erected case ready for lling and closing;

Fig. 5 is a plan view of a blank used in forming my improved beer bottle case; and

Fig. 6 is a perspective view of the beer bottle case ready to receive a charge of bottles.

Referring to the drawings, and particularly to Fig. l which shows the blank used in forming my improved case, 1 indicates the panel of the blank which in the erected case constitutes the bottom. Oneach side of the bottom portion 1 are side wall portions 2 and extending beyond the side wall portions are two top flaps 3 which when the case is lled and closed, form the top sealing flaps of the case. Transverse score lines 4 are provided at the side margins of the bottom panelvl berice tween the bottom panel and the side walls 2, and similar fold lines are provided at the junction of the top flaps 3 and side walls v2.

Extending from each end of the bottom panel 1 are the end flaps 5. There are, however, no score lines along the end margins of the bottom panel 1, but instead score lines 6 are formed in the end flaps along a line parallel with the margin of the bottom panel 1 but spaced from the bottom panel by a distance of, say, one inch, the score line 6 being formed with its convex face on the opposite side of the blank from the convex faces of the score lines between the bottom panel 1 and the side walls 2.

End aps 7 are provided at the ends of the side walls 2, these aps being of reduced width so that when the case is erected their edges will meet along the vertical middle line of the end Wall of the case, as shown in Fig. 4, the end iiaps 7 having score lines 8 similar to the score lines 6 of the end aps 5 and in alignment therewith.

Projecting from the edges of the flaps 7 at the ends remote from the end aps 5 are the top end flaps 9, and between these flaps and the aps 7 are score lines 10 similar to the score lines 4 which are in alignment therewith. Slits 11 are cut in the blank between the end liaps 5 and the flaps 7, and similar slits 12 are cut between the top flaps 3 and the end flaps 9.

In order to stiien the corners of the blank there is applied to the portion of the blank along the end edges of the bottom wall 1 and side walls 2 and the contiguous portions of the flaps 5 and 7 between the score lines 6 and 8 and the corners of the blank, a solution of a thermosetting resin which when hardened under heat and pressure in a die of angular cross section will form rigid corner sections at the junction of the bottom and side walls of the case and the end-forming aps.

In the manufacture of the improved case there is preferably employed a at blank of rectangular cross section of the desired dimensions and as a rst step in the procedure the blank is scored along the lines 4, 6, 8 and 10. Simultaneously with this operation, or as a succeeding step, there is applied to the face of the blank a resin solution along the areas indicated at 13 in Fig. l. In order to insure the absorption of the resin solution it is preferable to perforate the surface of the areas to be stiffened with closely spaced pin pricks, which may be easily done by running the blank beneath a pricking roller and then under a coating roller for applying the resin solution.

After the application of the resin solution the blanks are pressed between heated dies 14 of angular cross section, as shown in Fig. 2, the dies being of a size equivalent to the coated area 13 shown in the blank, the portions of the dies 14 corresponding to the coated area of the bottom and end walls being at, while the portions of the die corresponding to the coated areas of the iaps 5, 7 and 9 are substantially vertical.

The slots 11 and 12 may be cut in the blank and the ends of the aps 7 and 9 narrowed by cutting away the marginal portions at the same time that the corner sections are molded, by providing the molding members with a cutting attachment as is common in the cutting and shaping of sheet material. The cutting operation may, however, be performed at any other point in the operation. For example, if the score lines are formed by a press the cutting may be accomplished simultaneously with the scoring.

At the time the resin solution for stiifening the corners is applied stripes of resin solution are also applied to the bottom 1 of the case parallel with the score lines 4 between the bottom 1 and sides 2, as indicated at 15 in Fig. 1. When the corners are molded between the heated dies, the resin in the stripes 15 is also molded to form cover rails or runners 16 along the bottom wall of the case. These runners serve to space the bottom of the case from the oor, which is particularly desirable when the truck or warehouse oor is damp. The runners are also desirable where the cases are used for packing and for-storing fruit which requires ventilation. Such Cases have Ventilating holes in the walls and the runners provide spaces for the circulation of air through the staked` cases. l

After the corners are shaped by heat and pressure by the dies 14 the blank is ready to be erected into a case for illing and closing. Preferably the blanks Vare shipped to the user before the case is erected in order to save shipping space. To this end theblanks are stacked one on the other with each blank partially nested into the blank below, as shown in Fig. 3. As will be noted here, the unimpregnated portion of the board forming the wall of the blank between the corners is sufficiently dexible for the formed corners to tilt slightly outward when the blanks are stacked, so that the blanks will nest even though the stilened corners are rigid right angles. When the'blanks are stacked for shipment, as shown in Fig. 3, the aps 5, 7 and 9 fold outwardly along the score lines 6, S and 10, respectively, so that the stacked blanks with the formed corners take up very little more room than a stack of an equivalent number of hat blanks.

When the case is erected to receive the cans or other goods to be packed, the end flaps 5 are first roided to vertical position. The flaps 7 with the attached end aps 9 are then folded to vertical position along the score lines 8. The side Walls 2 are then folded to vertical position along therscore lines 4, thereby bringing the edges of the aps 7 together along the middle vertical line of the end of the case outside of the bottom iiaps 5. rhe aps 7 are stitched or otherwise secured to the flaps 5, thereby completing the end walls of the case which will be of double thickness throughout and also have around the bottom horizontal corner and the two vertical corners stiffened reinforcing sections which serve to hold the carton in shape under a heavy stacking load and also during the handling incidental to shipment.

After the case is erected as described it is ready to be packed and closed by means of any conventional paci'- ing and closing machinery such as now universally used for packing and closing cartons having the usual side and end top closing flaps. Such cartons have but one closing flap at each end whereas the improved carton, as shown in Fig. 4, has two end closing ilaps at each end. However, the flap-closing members of the machines commonly used for closing cartons are wide enough to simul-V taneously close the two ilaps 9 at each end of the carton.

The resin for stiffening the corners of the carton is shown as applied only to the portions forming the bottom and vertical corners at each end. The resinous material may at the same operation be applied along the edges of the end aps 9 and the top flaps 3 on each side of the slots 12 so that when the carton is filled and closed the case will be stiflened along end and side edges or" the top wall.

In Figs. 5 and 6 we have shown a somewhat modied form of case particularly intended for the distribution of Y continuation of the flaps 7 we provide short end aps 20 as a continuation of the top ap 3. We also provide at the edges of each of the 'top iiaps a lip portion 21. The

lank is treated with the resin solution along the meeting edges of the side walls 1 and i'laps 5, the side walls 2 and ilaps 7 and also the top ilaps 3 and the marginal aps 20, the marginal ilaps 20 being impregnated throughout their entire area. When the above described blank is pressed between the forming dies 13, rigid corners will be formed at the ends of the top flaps 3 so that when the top are closed the rigid marginalportions 20 will project into the space between the tops of the end ilaps 7 and the end iiap 5, which, as here shown, forms the outer end Wall of the case. At the same time the marginallips 2l will come together along the middle longitudinal line of the top wall of the `case.

A case so formed will remain closed during the handling of the cases, and if it is desired to seal the case for shipment, a strip of gurnmed tape may be placed over the meeting edges of the top aps 3 and down against .the end aps 5. The case is readily opened by cutting the tape along the meeting edges of the ilaps 3 and at the .ends of the ilaps 3 without in any way tearing the case, so that the case may be used repeatedly for the shipment of full bottles and the return of the empty bottles. By reinforcing the corners of the top flaps in the manner described the case will carry a normal stacking load when lying on its side as well as when resting on its bottom and also is much less liable to deformation by rough handling in shipment.

It will be understood that the cases herein illustrated represent embodiments of the invention in its preferred forms but that the invention is not limited to the cases illustrated except insofar as the structure thereof is recited in the appended claim.

We claim:

A packing case of paper board having a bottom wall with integral flaps folded at right angles to the bottom wall to form side and end walls, the end Wall flaps each having a score line spaced from said fold line and coextensive therewith, the portions of the paper board which extend from said score lines through said fold lines and part way only into said bottom wall being impregnated with a resin, thereby forming portions of angular cross section substantially coextensive in length with said fold line and rigid throughout.

References Cited in the file of this patent UNITED STATES PATENTS 426,810 Heinemann Apr. 29, 1890 1,347,530 Williamson July 27, 1920 1,425,914 Swift Aug. 15, 1922 1,600,396 Campbell Sept. 2l, 1926 l,9ll,908 Lell May 30, l933 1,997,718 Clair Apr. 1,6, 1935 2,033,855 Sloan Mar. 10, 1936 2,042,210 Clay May 26, 1936 2,335,345 Libit Nov. 30, 1943 2,385,898 Waters Oct. 2, 1945 2,402,548 Guyer June 25, 1946 2,496,965 Swingle Feb. 7, 1950

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