US2799442A

US2799442A - Box with automatic closure

Info

Publication number: US2799442A
Application number: US392937A
Authority: US
Inventors: Robert E Van Rosen
Original assignee: ROBERT GAIR CO Inc
Current assignee: ROBERT GAIR CO Inc; ROBERT GAIR COMPANY Inc
Priority date: 1953-11-18
Filing date: 1953-11-18
Publication date: 1957-07-16
Anticipated expiration: 1974-07-16

Description

ylfi, 1195? R. E. VAN ROSEN ,7

BOX WITH AUTOMATIC CLOSURE f 4 Sheets-Sheet 1 Filed Nov. 18. 1.953

5e l l r 78 1 l Ffi v I 68 as r ..L

' RE. VAN ROSEN 2,799,442

BOX WITH AUTOMATIC CLOSURE July 16,, 1957 4 Sheets-Sheet 2 Filed NOV. 18, 1953 July 16, 1957 Filed Nov. 18, 1953 R. E. VAN ROSEN 2,799,442

BOX WITH AUTOMATIC CLOSURE I 4 Sheets-Sheet 3 JulylG, 1957 VAN ROSEN 2,799,442

I BOX WITH AUTOMATIC CLOSURE 4 Sheets-Sheet 4 Filed Nov. 18, 1953 United States BOX WITH AUTOMATIC CLOSURE Application November 18, 1953, Serial No. 392,937

3 Claims. (Cl. 229-37) The present invention relates to boxes and more particularly to an automatic self-closing closure for boxes of the general type identified as folding boxes. According to the present invention a generally rectangular box having four vertical walls is provided with one or more closure flaps each hinged along an upper or lower edge of one vertical wall and hingedly connected -by webs to the corresponding edges of the walls on both sides of that "to which the closure flap is hinged. The webs are provided with generally diagonally disposed lines of weakening along which the webs may be folded inwardly as the closure flap is moved toward closed position. According to the present invention, the lines of weakening in the webs are not truly diagonal whereby the webs are somewhat distorted when the closure flap is moved toward closing position. The particular disposition of the lines of weakening is such that distortion of the webs yieldingly resists movement toward closed position and maximum distortion occurs before the closure flap reaches its final closed position. Continued movement of the closure flap toward closed position and beyond the point of maximum distortion brings about a reversal or overcentering of the spring eflYect arising from such distortion and thereafter the distorted webs serve to hold the closure flap in closed position. The closure flap, therefore, will snap into closed position or into opened position Whenever it is moved in an appropriate direction beyond the point where maximum distortion of the webs occur.

A folding box with such automatic closure is particularly useful in the retail trade where a merchant may purchase the boxes in fiat, folded condition and set them up when they are needed for packaging of merchandise. After the merchandise has been inserted in the box, the closure flap is moved toward closed position whereupon it snaps shut and the purchaser may take the merchandise home without the necessity for taping, tying with string, or the like. Furthermore, the box may 'be used by the purchaser for subsequent storage of the purchased article inasmuch as the automatic closure may be operated repeatedly without damage to the closure or to the box. The box of the present invention is particularly useful, for example, in the merchandising of light, bulky articles such as hats, shoes, garments, and the like.

The closure of the present invention may be applied in the form of one or more automatically closing flaps at atent O F the top or bottom or both. If the closure of the presshapes and proportions and that the present invention 2,799,442 Patented July 16, 1957 ice shall not be limited to the specific disclosures herein made.

In the drawings:

Fig. 1 is a plan vietw of a blank from which one embodiment of the present invention may be constructed;

Fig. 2 is an elevational view of a box which has been set up from the blank of Fig. 1 and in which the closure flap has been slightly moved toward closed position;

Fig. 3 is a view similar to Fig. 2 but showing the closure fiap moved further toward closed position;

Fig. 4 is a view similar to Fig. 2 but showing the box closed and with certain parts broken away to disclose the position of the Webs which serve to hold the closure flap in position;

Fig. 5 is a plan view of a blank from which a modified form of the present invention may be constructed;

Fig. 6 is a fragmentary elevational view of one end of a box made from a blank such as that shown in Fig. 5 and showing the closure slightly moved toward closed position;

Fig. 7 is a fragmentary sectional view taken in a plane such as that indicated at AA in Fig. 5, and showing the closure moved further toward closed position; and

Fig. 8 is a view similar to Fig. 7 showing the closure in closed position.

Referring now to the drawings, in Fig. 1 there is shown a blank for a simple rectangular box which may be of the general size and proportions of the familiar shoe box. The blank includes a front wall 10, a rear wall 12, an end wall 14 interposed between the

walls

10 and 12 and separated therefrom by

score lines

16 and 18. An opposite end wall 20 is separated from the rear wall 12 by a score line 22. A glue tab 24 is joined along a vertical edge of the end wall 20 by a score line 26. Glue or other suitable adhesive is positioned in the area indicated at 28 for securing the tab 24 to the left hand edge portion of the front wall 10 as viewed in Fig. 1 in a manner well known in the art. A stiffening flange 11 is joined along a score line 13 along the upper edge of the front wall 10.

The blank may be provided with any suitable form of bottom closure flaps including flaps identical with the top closure flaps to be described hereinbelow. For simplicity of disclosure, however, there is shown herein a simple bottom closure construction comprising

end flaps

30 and 32 joined with the

end Walls

14 and 20 by

score lines

34 and 36. A main bottom closure flap 38 is joined along the lower edge of the front wall 10 by a score line 40 and is provided with a tuck-in lip 42 hinged thereto along a score line 44. The simple bottom closure just described is closed after the box has been erected by first folding the

end flaps

30 and 32 inwardly and thereafter folding the main bottom flap 38 along the score line 40. The tuck-in fiap 42 is inserted between the

end flaps

30 and 32 and the adjacent lowermost edge 46 of the rear wall 12. The closure just described forms no part of the present invention, it being understood that any suitable form of bottom closure may be used so long as it is of the type which will tend to hold the box in erected position for insertion of contents through the top.

The top closure, in accordance with the present invention, comprises a main top panel 48 joined along a score line 50 with the rear wall 12. The main panel 48 is also joined along

vertical score lines

52 and 54 with

webs

56 and 58 which have a generally triangular configuration and which are respectively joined with the

end walls

14 and 20 along

horizontal score lines

60 and 62. A line of weakening 64 extends from the intersection of the

score lines

60 and 52 generally diagonally of the web 56 and in a particular angular relationship which will be described hereinbelow. Such line of weakening may com r O prise a score line or a combination of scoring and cut ting as illustrated in this particular form of the invention. As shown in the drawings and particularly in Fig. 1, the line of weakening 64 may comprise a cut 66 which extends from the intersection of the

score lines

60 and 52 for a relatively short distance beyond which there is a score line interrupted by an arcuately curved cut. 68 to define a tab 70 to be described hereinbelow. Beyond the tab 70, the score line extends to the margin of' the web 56.. It will be apparent that the .web 56 will tend to fold along the line of weakening 64 and that the tab 70 will project outwardly. when suchfold is made- The web 58 at the opposite .end of the box is provided with a line of weakening indicated generally at 72 which is-similar in all respects .with the line of weakening 64 and includes, for this particular form of the-invention a cut 71 and a curved portion 75 defining a curved tab .73.

Since the box.which is to be erected from the blank shown in Fig. l is a rectangular box, the walls 12 and '14 for example,. will occupy planes which intersect at right angles along the score line 18. Similarly, the

score lines

52 and 60 intersect at right angles. Therefore, thenatural fold line for the web 56 would be along a line .bisecting .the anglebetween score lines .60 and 52. If:the line of weakening 64 were to be thus disposed, the-web 56 could be foldedinwardly as the main closure panel 48 is folded inwardly along its score line 50 Without distortion of the web 56 and such action would be resisted only by such spring as is left in the box board along-the score lines. This residual spring, of course, would tend to-move the main closure panel upwardly and away from closed position. by precreasing, as to kill residual spring, the main closure panel 48 might lie limply in closed position but such a closure obviously would be of little value in maintaining contents within the box. According to the present invention, the lines of weakening 64 and 72 in the

webs

56 and 58 do not bisect the angle between the respective score lines which define such webs. Thus the angle a between the score line 60 and the line of weakening 64 is slightly greater than the angle [2 between the line of weakening64 and the score line 52. Similarly, the angle is slightly greater than the angle d in the web 58. As a practical matter, the difference between the angles may be from one to four degrees. For example, angles a and c may be 46 and the angles 17 and d may be 44, in a rectangular box of the type chosen for illustration. Since the lines of weakening 64 and 72 are thus displaced from the natural fold lines of the

webs

56 and 58, distortion will occur when the webs are tucked inwardly incident to moving the main closure panel 43 towards closed position.

The blank so far described may be erected into a fold ing box with a self-closing top closure which will automatically remain in closed position as will be described hereinbelow. However, it has been found preferable to provide a reinforcing panel 74 joined to the top panel" 64. At the lower end the panel 78 is cut at 38 at anangle to coincide generally with the edge 94 of the-web 56. The panel 80 is similarly cut at 90 and 92. be understood, however, that the particular conformation of the edges 94 and 96 of the

webs

56 and 58 is not If the score lines were so weakened, as

It will critical to the present invention and they might be curved forwardly and downwardly-alongtheline 76--as-viewed- 4 in Fig. l, in order that the reinforcing panel 74 may lie flatwise in registry with the main panel 48 and the

small panels

78 and 80 may lie in general registry with the triangular portions of the

webs

56 and 58 which lie above the lines of weakening 64 and 72.

The blank shown in Fig. 1 will normally be folded first along the line established by the score lines 18, 52 and 82 to bring the glue tab 24 in position to be secured to the front Wall 10. After it is thus secured the blank is ready for shipment to the customer. When the customer desired to set up the blank the various score lines described hereinabove will be precreased in appropriate directions as is usual in setting up folding boxes. Thus the score lines 16 and 22 will be creased so that the

vertical walls

10, 14, 12 and 20 will define a hollow rectangle. The end flaps 30 and 32 of the bottom closure will be folded inwardly and the main bottom panel 38 with its tuck-in tab 42 will be positioned in known manner. The box then will be in openerected position. The stiifening flange 11 will be folded along the score line 13 to extend inwardly of the box to stiffen the upper edge of the front wall 10. The reinforcing panel 74 and

small panels

78 and 80 will be folded downwardly along the line 76 to form the double thickness. top closure flap. The box is now ready to be closed and this is effected by starting the

webs

56 and 58 to fold along their lines of weakening 64 and 72, inwardly and downwardly of the mouth of the container. This brings the container into the position illustrates in Fig. 2.

As shown in Fig. 2, the

webs

56 and 58 have been moved inwardly and downwardly to such an extent that the tabs 70 and 73 will snap under the

lower edges

88 and 92 respectively of the

small panels

78 and 80. The tabs 70 and 73 will thereafter serve to hold the

small panels

78 and 80 snugly against the upper triangular portions of the webs 56 and58 and thusto hold the reinforcing panel 74 flat against the main top panel 48. Continued closing of the box from the position shown in Fig. 2 will swing the

webs

56 and 58 inwardly and downwardly against increasing resistance due to distortion until, as shown in Fig. 3, the

webs

56 and 58 have reached the position in which the triangular portions thereof below the lines of weakening 64 and 72 respectively will lie in a plane substantially normal to the

end walls

14 and 20. In this position maximum distortion occurs and the energy stored in the distorted, resilient box-board from which the container is made is at a maximum. Continued downward movement of the closure toward the position shown in Fig. 4 willdepress the lower triangular portions of .the webs 56 and .58 below the horizontal whereupon the energy stored in the distorted parts of the box. will be effective to spring the webs 56 2111i 58 downwardlyto snap the top closure into closed position asfillustrated in Fig. 4. As shown in said Fig. 4 the in folded

webs

56 and 58 are inclined downwardly into the body of the box being constantly urged into such position by the energy stored in the distorted b x parts. When the box is opened by lifting the

top closure flap

48, 74 the

webs

56 and 58 will again approach the position shown in Fig. 3 and during this period opening will be increasingly resisted. Further opening will bring about a reversal of the direction in which the stored energy is effective and the closure will thereupon snap into a substantially open position such as that shown in Fig. 2.

The action of the closure of the present invention is comparable with that achieved by the use of an overcentering spring in many familiar applications. The spring effect in the present structure is provided by the inherent resiliency of the box-board, which may be chipboard, kraft. board or any of the paper-boards ordinarily used in the manufacture of cartons, folding boxes and the like. The overcentering effect is the result of the particular construction of the

webs

56 and 58 which have lines of weakening angularly offset from the natural foldlines"fo'r such webs. The principle of'such overcentering effect will be explained with particular reference to the form of the invention shown in Figs. 1 through 4.

Since the angle a in web 56 is slightly greater than angle b an imaginary line normal to any point along the line of weakening 64 will have a greater length between line 64 and score line 60 than it has between the line 64 and score line 52. Thus, if the web 56 be folded inwardly and the top panel 48 be folded downwardly from the flat blank shown in Fig. 1 such action would swing the end wall 14 forwardly along the score line 18. Because of the unequal lengths of the imaginary line aforesaid, the end wall 14 would tend to assume a final position wherein the angle between the rear wall 12 and the end wall 14 would be greater than a right angle. However, since the box is glued together and is set up in open rectangular form before the web 56 is folded inwardly, the rightangular relationship between

walls

12 and 14 is already established. Thus, referring to Figs. 2 and 3, the inward folding of the

webs

56 and 58 is accompanied by the exertion of force tending to spread the

end walls

14 and 20 apart.

Such force will be exerted along lines generally normal to the lines of weakening 64 and 72 and thus will tend to compress or distort the lower, larger triangular portions of the

webs

56 and 58. Also the force will be resisted by the

end walls

14 and 20 along the fold lines 60 and 62 and will cause bulging along such lines.

The distortion and bulging will reach a maximum when the lower triangular portions reach a substantially horizontal or dead-center position. When such dead-center position is passed in a downward direction the distorted parts will tend to spring back to undistorted condition and in doing so will snap the closure to closed position.

The reinforcing panel 74 and the

small panels

78 and 80, if provided, serve to stiffen the top closure panel 48 and the upper, smaller triangular portions of the

webs

56 and 58. Such stiffening serves to confine distortion to the lower triangular portions of the

webs

56 and 58 and to the

end walls

14 and 20 and makes operation of the closure more definite and reliable particularly when relatively light board is used.

Referring now to Figs. through 8, there is shown a different form of closure embodying the present invention. In these figures the closure is shown applied to a box which may be generally of the size and proportions suitable for millinery. In Fig. 5 thereis shown a plan view of the innersurface of a blank from which the box shown in Figs. 6 through 8 may be erected. The blank comprises a rear wall 100,

side walls

102 and 104 and two front wall parts, 106 and 108. The walls and wall parts aforesaid are defined by

vertical score lines

110, 112, 114 and 116 and the

front wall parts

106, 108, are of such size that the

edges

118 and 120 thereof may be overlapped to form a front wall of the same width as the rear wall 100. A bottom closure of any desired or convenient form may be used. For purposes of illustration, there has been shown bottom end flaps 122 and 124 hinged respectively along

score lines

126 and 128 to the

end walls

102 and 104. A bottom closure flap 130 is hinged along a score line 132 to the rear wall 100 and is provided with tuck-in flap 134 hinged thereto along a score line 136.

A top closure panel 138 is hinged along a score line 140 along the upper edge of the rear wall 100. In this form of the invention the top closure panel 138 is approximately one-half the width of the open mouth of the erected box. A second top closure flap of approximately the same width is arranged to fold along the upper edge of the front wall, the two top closure panels thus provided being arranged to meet along a transverse center line of the open mouth of the erected box. The second top closure panel may be made in two parts as shown in the blank in Fig. 5 although it will be understood that such construction is illustrated because the main vertical seam of the box extends vertically of the front panel and it will beapparent that a different construction may be adopted in the event-the main seam of the box liesadjacent one corner thereof or is positioned in some other panel or wall. The second top closure panel comprises a panel part 139 hinged along a score line 141 to the panel 106 and a panel part 142 hinged along a score line 144 to the panel 108. The panel part 142 and the front Wall panel 108 are adapted to receive a stripe of glue or other suitable adhesive within the area generally indicated at 146 for the purpose of securing the edge portions and 118 together to form the main seam of the box.

A'web indicated generally at 148 is hinged along a score line 150 to the end wall 102 and is also hinged along

score lines

152 and 154 respectively to the

closure panels

138 and 139. Lines of weakening generally indicated at 156 and 158 extend generally diagonally inwardly of the web 148. The angle'e between the line of weakening 156 and the score line 150 is slightly greater than the angle 1 between the line of weakening 156 and the score line 152. Similarly the angle g between the line of weakening 158 and the score line 150 is greater than the angle 11 between the line of weakening 158 and'the score line 154. The difference between these angles may be substantially the same as that discussed above in connection with the first form of the present invention.

The upper edge of the web 148 is preferably cut away to facilitate folding, as shown in Fig. 5. Thus the edge 160 slants downwardly from the upper end of score line 152 to a point of intersection with a continuation of the line of weakening 156. A similar inclined edge 162 extends from the upper end of score line 154 to a point of intersection with the line of weakening 158. A generally horizontal portion 164 joins the

inclined edges

160 and 162.

A web 166, which may be identical with the web 148,

is hinged along a score line 168 to the end wall 104 and along

score lines

170 and 172 to the closure panel 138 and panel part 142 respectively.

If so desired, a reinforcing panel may be provided for stiffening the top closure made up of

parts

139 and 142. Such stiffening panel may comprise panel parts 174 and 176 hinged respectively along

score lines

178 and 180 to the upper edges of the

top closure parts

139 and 142.

Small panels

184 and 186 preferably are provided with inclined lower edges 192 and 194 which are disposed at such an angle as to coincide substantially with the

inclined portions

160, 162 for example, of the upper edges of the

webs

148 and 166 when the stiffening panel 174 is folded flatwise into engagement with the

top closure panel

139, 142. Each of the small panels 184 is provided with a notch 196 and 198 for a purpose to be described.

The line of weakening 156 in web 148 and the corresponding line of weakening 200 in web 166 may consist primarily of a score line having cuts 202 and 204 aligned therewith in the region of the

score line

150 and 168 respectively. At their outer ends the lines of weakening 156 and 200 may be provided with irregular cuts to define

small tabs

206 and 208 respectively which will project outwardly from the

webs

148 and 166 when the same are folded along the lines of weakening 156 and 200. These

small tabs

206 and 208 are so positioned as to snap into engagement with the notches 196 and 198 in the

small stiifening panels

184 and 186, as will be described hereinbelow.

Also, if so desired, a locking tab 210 may be formed along the upper edge of the closure panel 138. The tab 210 has

tongues

212 and 214 for insertion in

openings

216 and 218 formed respectively in the

closure panel parts

139 and 142. The tab 210 (if provided) may be availed as a supplemental lock for the top closure panels.

Inasmuch as the front wall of the box is formed of corresponding halves which are joined along the

edges

118 and 120 as described above, it is preferable to provide a plurality of relief-notchesalong various score'lines in order to avoid the necessity for folding double thicknesses of box board. Such provision is commonin the box making art and in this connection the blank may be provided with

relief notches

220, 222, 224 and 226 which are so shaped and located in the zone of the main seam of the box as to function in the desired manner. An inspection of Fig. 6'wi1l reveal the ultimate disposition of the

relief notches

220 and 224, 226, for example.

The blank shownin Fig. 5 will be folded along two vertical score lines such as 112 and 114 to bring the edges 118 and 120'into overlapping position with edge 120 uppermost. Adhesive in the zone 146 will be availed of to form the main seam of the box. The box is then ready for shipment to the customer in fiat folded form. When the box is set up it will be creased along the remaining vertical score lines to bring it to hollow rec tangular form andthe bottom closure flaps 122, 124 and 130'will be moved to closed position in known manner. The box is now set up in rectangular form with the top open topreceive contents.

When it is desired to close the boxfor the first time, the stiffening panel 174, 176 with associated

small panels

184 and 186 is folded inwardly and downwardly along the score lines 178, and 180 into the position illustrated in Fig. 6. It should be noted that in Fig. 6 the box has been turned into a position wherein the wall 100, herein arbitrarily referred to as the rear wall, is in the front part of the view. As shown in said figure, the notch, 196 in panel 184 lies adjacent tab 206 in web 148. A'similar relation is established between the notch 198 and the tab 208 attheopposite end of the box. The

webs

148 and 166 are thenpressed inwardly to initiate folding along the lines of weakening 156, .158, 200 and 230. The

top closure panels

138 and 139, 142 will thereupon move inwardly and downwardly toward closed position. As suchmovement continues the notches 196 and 198 will become seated behind the

tabs

206 and 208 and thereafter will remain in such relationship to hold the stiffening panel 174, 176 snugly against the

closure panel

139, 142.

Further movement of the closure toward closed position will bring the parts into the position shown in Fig. 7 wherein the central portions of the

webs

148, 166 will approach a generally horizontal position. Movement up to this point meets with increasing resistance due to distortion of the webs 148' and 166 and of adjacent walls such as the

end walls

102 and 104, all as explained above in connection with .Figs. 1 through 4.. Maximum distortion occurs at approximately the position illustrated in 7 Fig. .7. As the central portions of the

webs

148 and 166 are moved beyond the dead center position they will snap downwardly towards the position shown in Fig. 8.

The over-centering spring action exerted by the closure shown in Figs. 5 through 8 is substantially the same as that described above in connection with Figs. 1 through 4. Thus the lines of weakening 156, 158, 200 and 230 are offset from the natural fold lines of the

webs

148 and 166 in such manner that imaginary lines normal to the lines of weakening have excessive length below the lines of weakening and bring about distortion as heretofore described.

It will be noted that the closure flaps 138 and 139, 142 are of such length as to meet in the center of the top opening of the box. It is preferred to provide the closure panel 138 with an extension lip 232 which will overlap the

closure panel

139, 142 as shown in Fig. 8. In the event a locking tab such as 210 isprovided the

tongues

212 and 214 thereof may be inserted in the openings 216 and 218 (see Fig. 5) to lock the top closure flaps in the position illustrated in Fig. 8.

From the above detailed description of two embodiments of the present invention, it will be apparent that the principal feature of the invention lies in the provision of'webs hingedly connected'with'- opposite ends of -a-cloarcane sure flap and with the walls adjacent the wall from which the closure flap-extends, which webs are provided with lines of weakening ofifset from the natural fold lines which such webs would tend to follow when tucked inwardly of the closure-flapas the latter is moved towards closing position. The otfsetis such that the portion of the web lying between the line of weakening and the adjacent wall provides lever arms whose effective lengths are greater than corresponding lever arms between the line of weakening and the edge of the closure flap to which-the web is joined. Thus when the flap is moved towards closed position the web-portion having the longer lever I to move the Webs towards a position in which distortionis reduced. The tendency towards such movement causes the closure to spring towards closed position and to remain closed until sufficient force is applied to the closure to bring the webs upwardly through the position of maximum distortion whereupon over-centering will again occur and the webs will spring the closure into substantially open position.

I claim:

1. In a box made of paperboard, the combination of four rectangularly disposed side walls, a bottom closure lying in a plane substantially normal to said side walls when in closed position, and a top closure including at least one rectangular flap hingedly joined to the 'upper edge of one of said side walls and adapted to be folded along said edge into a plane substantially normal to said side walls to assume a closed position, a pair of webs, each of said webs being hingedly joined to one side edge of said closure flap and tothe upper edge of a side wall contiguous with that to which said closure fiap is hinged, each of said webs having a line of weakening formed therein extending angularly from the intersection of the upper edges of said contiguous wall and the wall to which said closure flap is hinged and defining an angle with the upper edge of said contiguous side wall which is slightly greater than the angle which it defines with the side edge of said closure flap, and a rectangular flap hinged to the free edge of said closure flap and having panels hinged at the opposite ends thereof, said rectangular flap being adapted to be folded flatwise against the inner surface of said closure flap to stiffen said closure flap and said panels being adapted to lie flatwise respectively against the portions of said webs lying above the angularly ex tending lines of weakening therein whereby when said closure flap is moved to closed position said panels will serve to urge the inwardly folded webs downwardly into closure locking position.

2. In a box made of paperboard, the combination of four rectangularly disposed side walls, a bottom closure lying in a plane substantially normal to said side Walls when in closed position, and a top closure including at least one rectangular flap hingedly joined to the upper edge of one of said side Walls and adapted to be folded along said edge into a plane substantially normal to said side walls to assume a closed position, a pair of webs, each of said webs being hingedly joined to one side edge of said closure flap and to the upper edge of a side wall contiguous with that to which said closure flap is hinged, each of said webs having a line of weakening formed therein extending angularly from the intersection of the upper edges of said contiguous wall and the wall to which said closure flap is hinged and defining an angle with the upper edgeof said contiguous side wall which is slightly greater than the angle which it defines with the side edge of said closure flap, a rectangular flap hinged to the free edge of said closure flap and having panels hinged at the opposite ends thereof, said rectangular flap being adapted to be folded flatwise against the inner surface of said closure flap to stiffen said closure flap and said panels being adapted to lie fiatwise respectively against the portions of said webs lying above the angularly extending lines of weakening therein whereby when said closure flap is moved to closed position said panels will serve to urge the inwardly folded webs downwardly into closure locking position, said panels terminating along a line substantially coinciding with at least a part of the length of the angularly extending lines of weakening in said webs, and tabs extending from the portions of said webs lying below the lines of weakening therein upwardly across said lines of weakening to engage the terminal edges of said panels when the closure is moved to closed position thereby to lock said panels in flatwise engagement with the portions of said webs lying above the lines of weakening therein.

3. In a box made of paperboard, the combination of four rectangularly disposed side walls, a bottom closure lying in a plane substantially normal to said side walls when in closed position, and a top closure including at least one rectangular flap hingedly joined to the upper edge of one of said side walls and adapted to be folded along said edge into a plane substantially normal to said side walls to assume a closed position, a pair of webs, each of said webs being hingedly joined to one side edge of said closure flap and to the upper edge of a side wall contiguous with that to which said closure flap is hinged, each of said webs having a line of weakening formed therein extending angularly from the intersection of the upper edges of said contiguous Wall and the wall to which said closure flap is hinged and defining an angle with the upper edge of said contiguous side wall which is slightly greater than the angle which it defines with the side edge of said closure flap, a rectangular flap hinged to the free edge of said closure flap and having panels hinged at the opposite ends thereof, said rectangular flap being adapted to be folded fiatwise against the inner surface of said closure flap to stiffen said cloure flap and said panels being adapted to lie flatwise respectively against the portions of said webs lying above the angularly extending lines of weakening therein whereby when said closure flap is moved to closed position said panels will serve to urge the inwardly folded webs downwardly into closure locking position, said panels terminating along a line substantially coinciding with at least a part of the length of the angularly extending lines of weakening in said webs, notches formed in the terminal edges of each of said panels, and tabs extending from the portions of said webs lying'below the lines of weakening therein upwardly across said lines of weakening to engage the notches in the terminal edges of said panels when the closure is moved to closed position thereby to lock said panels in flatwise engagement with the portions of said webs lying above the lines of weakening therein.

References Cited in the file of this patent UNITED STATES PATENTS 1,103,186 Feldmeyer July 14, 1914 2,002,005 Gottlieb May 21, 1935 2,317,223 Rottman Apr. 20, 1943 2,326,417 Ullrich Aug. 10, 1943 2,336,731 Henderson Dec. 14, 1943 FOREIGN PATENTS 22,313 Great Britain Oct. 10, 1911 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,799,442 July 16, 1957 Robert E. Van Rosen 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.

In the grant, lines 2 and 3, for 'assig'nor to Robert Gair Company, Inc. of New York, N. Y. a corporation of Delaware" read --assignor to Continental Can Company, Inc. a corporation of New York-; line 12, for "Robert Gair Company, Inc. its successors" read --Continental Can Company, Inc. its successors--; in the heading to the printed specification, lines 3 to 5, inclusive, for "assignor to Robert Gair Company, Inc. New York, N. Y. a corporation of Delaware" read --assignor to Continental Can Company, Inc. a corporation of New York--.

Signed and sealed this 3rd day of December 1957.

iSEAL) ttest: KARL H. AXLINE ROBERT C. WATSON Attestlng Officer Comnissioner of Patents