US3348755A

US3348755A - Gable top container

Info

Publication number: US3348755A
Application number: US606747A
Authority: US
Inventors: George E Macewen
Original assignee: Phillips Petroleum Co
Current assignee: Huhtamaki Consumer Packaging Inc
Priority date: 1967-01-03
Filing date: 1967-01-03
Publication date: 1967-10-24
Anticipated expiration: 1984-10-24
Also published as: FR1577263A; ES146210U; NL6800014A; GB1190131A; DE1611964A1; ES146210Y

Description

Oct. 24, 1967 G. E. M EWEN 3,343,755

GABLE TOP CONTAINER Filed Jan. 5, 1967 3 Sheets-Sheet 1 FIG.

INVENTOR. G E MacEWEN ATTORNEYS Oct. 24, 1967 MacEwEN 3,348,755

GABLE TOP CONTAINER Filed Jan. 5, 1967 3 Sheets-Sheet 2 INVENTOR. G E. MacEWEN A 7' TORNEVS Oct. 24, 1967 G. E. M EWEN GABLE TOP CONTAINER Filed Jan. 5, 1967 3 Sheets-Sheet 5 INVENTOR. G E. Mac EW EN BY WM A T TORNE VS 3,348,755 GABLE TOP CONTAINER George E. MacEwen, Fulton, N.Y., assignor to Phillips Petroleum Company, a corporation of Delaware Filed Jan. 3, 1967, Ser. No. 606,747 6 (ilairns. (Cl. 229-17) ABSTRAUT OF THE DISCLOSURE The snap action score lines in each roof panel of an end open gable top container comprise apair of grooves substantially parallel to the plane of the infolded end panel which forms the spout, one being above and the second one being below the infolde-d end panel to form an I beam during opening of the container. A second pair of grooves, extending from the upper ends of the first pair coverage on the midpoint of the upper edge of the roof panel, while a third pair of grooves, extending from the lower ends of the first pair, converge on the lower corner of the roof panel contiguous to the spout.

This invention relates to blanks for forming gable top containers and to the resulting containers. In a specific aspect the invention relates to an improved snap-action score line configuration for end open gable top containers. The invention is particularly applicable to gable top containers of rectangular cross section formed from a paperboard blank coated on one or both sides with a theroplastic material. These containers are commonly used in the dairy industry for packaging milk, orange juice, lemonade and the like. The gable top closure structure consists generally of opposed front and rear roof panels inclined to make the gable formation, and a pair of tri angular-shaped end closure panels inclined upwardly between the front and rear roof panels. These end closure panels have integral fold-back panels that assume a position lying against the underside of the front and rear roof panels. The fold-back panels, and the front and rear roof panels, are formed with integral ridge panels, which get to be disposed in vertical contacting relation and are joined together by some form of adhesive, usually by a bonding of the thermoplastic coating, to form the ridge of the gable top.

In the past, numerous configurations of snap action score lines have been proposed for the paperboard gable top containers. While many of these configurations operate satisfactorily for the large containers, i.e. half gallon and gallon capacity, difiiculties have been encountered in employing such configurations in the half-pint, pint and quart containers. Some of the difficulties result from the use of lighter, less rigid paperboard in the smaller containers.

Accordingly, it is an object of the invention to provide a new and improved snap action score line configuration for gable top containers. It is an object of the invention to provide a snap action score line configuration which can be employed with lightweight containers as well as the more rigid containers.

Other objects, aspects and advantages of the invention will be apparent from a study of the specification, the drawing and the appended claims to the invention.

In the drawing, FIGURE 1 is a perspective view of a container embodying the invention, FIGURE 2 is a plan view of the paperboard blank from which the container of FIGURE 1 is formed, FIGURE 3 is a perspective view of the gable top structure in partial cross section in a partially opened condition, FIGURE 4 is a perspective view of the gable top structure in partial cross section in an advanced open condition, and FIGURE 5 is a States Patent 3,348,755 Patented Get. 24, 1967 perspective view of the gable top structure in the fully open condition after the tape has been removed.

Referring to FIGURE 2, the rectangular blank is provided with

vertical score lines

12, 13, 14 and 15, extending upwardly from the lower edge of the blank to a series 16 of horizontally extending

score lines

16a, 16b, 16c, 16d and 16e. The

score lines

13, 14 and 16b define a front side wall panel 17.

Score lines

15 and 16d, and 12 and 16e define

panels

18 and 19, the free edges of which, in the formed container, are overlapped and joined by a permanent adhesive bond to from a rear side wall panel which is located opposite front side panel 17. End wall panels 21 and 22 are defined by

score lines

12, 13 and 16a and 14. 15 and 160, respectively. Horizontal score line and 160 are located lower on the container than

score lines

16b, 16d and 16e to substantially reduce the thickness of the folds at adjacent lower corners of the closeure panels. In other words, the spacing part in the vertical plane of the bend of each roof panel into its vertical container wall from the bend of each end closure panel into its vertical container wall permits smaller and more attractive folds in the resulting corners of the container. With the scoring arrangement shown in FIGURE 2, the

panels

17, 21, 22 and the rear wall panel formed by

panels

18 and 19 are all of equal width.

The

vertical score lines

12, 13, 14 and 15, which are located at the vertical corners of the completed container, extend upwardly past score lines 16 as at 23, 24, 25 and 26, and terminate at the top edge of the blank. Horizontal score line 27 is located a short distance downwardly from the top edge of the blank When the blank has been folded to tubular form and overlapping edges of the

panels

18 and 19 have been joined together, a bottom closure 20 (FIGURE 1) is permanently sealed to the lower end of the tubular formation.

Score lines

24, 25, 16b and 27 define the front roof closure panel 28.

Score lines

24, 25 and 27 define the rib panel 29, surmounting the front roof panel 28.

Score lines

23, 26, 16d, 16e and 27 define the rear roof closure panel composed of

sections

31 and 32.

Score lines

26, 23 and 27 define the rib panel, comprising

sections

33 and 34. surmounting the rear roof panel.

Score lines

23, 24, 16a and 27 define a rectangular end closure panel. This end closure panel is provided with converging score lines 35 and 36 which at their upper ends intersect the score line 27 medial of

score lines

23 and 24, thus defining a triangular end closure panel portion 37 and a pair of triangular fold-

back panel portions

38 and 39.

Score lines

23, 24, 27 and 41 define

rib panels

42 and 43, surmounting fold-

back panel portions

38 and 39, respectively.

Score lines

25, 26, 16c and 27 define a second rectangular end closure panel. This second end closure panel is provided with converging

score lines

44 and 45, which, at their upper ends, intersect score line 27 medial of

score lines

25 and 26, thus defining a triangular end closure panel portion 46 and a pair of triangular fold-

back panels

47 and 48.

Score lines

25, 49, 26 and 27 define

rib panels

51 and 52, surmounting fold-

back panel portions

47 and 48, respectively. In the completed container, the pair of

opposed roof panels

28 and 31, 32 are inclined toward each other and overlie the top of the tubular body formed by

side walls

17, 21, 22 and 18, 19. The pair of opposed triangular

end closure panels

37 and 46 are infolded between

roof panels

28 and 31, 32 from the opposite gable ends formed by the latter, and with their apexes located at the central area of the gable. The

fold lines

44, 45, 35 and 36 which join each pair of triangular fold-

back panels

47, 48 and 38, 39 to the opposite sides of triangular

end closure panels

46 and 37 are in proximity with the roof panels, the fold-back panels being folded against the underside of said roof panels.

Ridge panels

51 and 52 surmounting fold-

back panels

47 and 48 are hinged together at the apex of end closure panel 46 and are folded about the hinge joinder score line 49 in face-to-face relation, between the

ridge panels

29 and 33 surmounting the roof panels. Similarly,

ridge panels

42 and 43 surmounting fold-

back panels

38 and 39 are hinged together at the apex of end closure panel 37 and are folded about the hinge joinder score line 41 in face-toface relation, between

ridge panels

29 and 33. The ridge panels are heated to form a bond between the contacting thermoplastic coatings to form the ridge structure of the. gable top.

Score lines

23, 24, 25 and 26 are of extended width, with respect to the remainder of

score lines

12, 13,14 and 15, with the extension being in a direction toward the center of the respective roof panel.

Thusscore lines

24 and 25 are of extended width in the direction of the center of the front roof panel 28, While

score lines

23 and 26 are of extended width in a direction toward the center of the rear roof panel formed by

panels

31 and 32.

When the blank of FIGURE 2 is folded on the

score lines

12, 13, 14 and 15 about the square mandrel of the container erecting machine, the closure panels above the series of score lines 16 form a square tubular cross section in a direction transversely of the container. When the top closure panels are folded inwardly, the greater width of

score lines

23, 24, 25 and 26 provides extra material for the

end closure panels

46, 47, 48 and 37, 38, 39 and surmounting

rib panels

51, 52 and 42, 43, whereby in the formed and sealed contrainer,

rib panels

43 and 51 have a greater combined length than rib panel 29 surmounting the front roof panel 28. Similarly

rib panels

52 and 42 have a greater combined length in the formed and sealed container than the rib panel formed by

panels

33, 34 surrounding the

rear roof panels

31, 32. This, in turn, results in the hinge joints on

score lines

41 and 49 abutting or slightly overlapping at the center of the laminar ridge structure formed by bonding the rib panels together.

In the second end closure panel, which serves as the pouring spout, converging

score lines

44 and 45 intersect horizontal score line 27 midway between

score lines

25 and 26. Vertical score line 49 extendsupwardly from the intersection of

score lines

44 and 45 to the top edge of the blank. The weakened line of severance 60 is located in the upper part of

panel portions

47, 46 and 48 below horizontal score line 27. The weakened line of severance 60 would intersect

score lines

44 and 45 at points below the junction of

score lines

44 and 45 except that

score lines

44 and 45 are discontinuous, or interrupted, in the area of the weakened line of severance 60.

Score lines

44 and 45 stop short of line 60 to prevent leakage which could otherwise occur by capillary action through the slit and along the score lines. Eliminating all score line grooves in the vicinity of the line 60 provides a flat surface completely around the periphery of the slit, thus permitting a liquid tight seal to be effected between the tape 61 (FIGURE 1) and the container. The weakened line of severance is preferably formed in three sections, each end section 60a and 60b being formed by a series of zig-zag incisions and the center section 60c being formed by a straight, horizontal incision. Center section 60c extends completely across panel 46 and preferably extends into

panels

47 and 48. The straight center section 600 provides for easier separation of the pouring spout section of

end panel

46, 47, 48 from the upper portion thereof above severance line 60. This is particularly important in view of the large amount of paperboard in the relatively small area of the triangle formed by

lines

44, 45 and 600 as well as the fold lines formed in this area by the fabrication of the central laminar ridge and subsequent opening and closing of the pouring spout.

A strip of tape 61 (FIGURE 1) is bonded to the second end closure panel in overlying relation to the weakened line of severance 60. The tape 61 is applied over the weakened line of severance 60 and heat sealed to the entire marginal surface about the weakened line of severance. The

tape 61 can be formed of thermoplastic material or it can be a non-thermoplastic material provided with a coating of thermoplastic material compatible and heat-sealable to the thermoplastic coating on the container. It is presently preferable that the non-thermoplastic material have a heat reflective outer surface to prevent any weakening of the bond between tape 61 and the container during the time the top section of the container is being subjected to heat in preparation for sealing the rib panels to form the central laminar ridge. The ends 62 of tape 61 extend beyond the ends of the second end closure panel to provide grasping tabs.

In order to provide a snap action for opening and closing the pouring spout, the front roof panel 28 is provided with

score lines

71 and 72, extending upwardly from the intersection of horizontal score line 16b and vertical score line 25 to a point on score line 27 midway between

vertical score lines

24 and 25. Score line 71 is preferably formed in three

sections

71a, 71b, and 71c. Score line 72 is preferably formed in three

sections

72a, 72b and 72c.

Straight line sections

71b and 72b are substantially parallel to an imaginary line 73 between the vpoint on score line 27 midway between

score lines

24 and 25 and the intersection of score lines 16!) and 25. Imaginary line 73 closely approximates the plane of the triangular end closure panel 46 in the infolded, sealed condition. If side walls 17. and 18, 19 were of greater width than walls 21 and 22,

score line sections

71a and 72a would intersect score line 27 at or closely adjacent to the intersection of imaginary line 73 with score line 27, or in other words at or closely adjacent to the intersection of the score line 27 with the plane of panel 46 in the infolded, sealed condition of the container. Score section 72b is positioned in root panel 28 above the imaginary line 73 while score section 71b is positioned in root panel 28 below imaginary line 73. Score sections 71c and 720 extend from the lower ends of

score sections

71b and 72b, respectively, to converge together at the intersection of

score lines

16b and 25.

Score sections

71a and 72a extend from the upper ends of score sections 71b and 7211, respectively, to the point on score line 27 midway between

score lines

24 and 25. The

rear roof panel

31, 32 is provided with

score lines

74 and 75, corresponding to score

lines

71 and 72, respectively, comprising

score sections

74a, 74b, 74c and 75a, 75b, 75c, respectively.

If sections 71b and 741) were used alone, or

with'sections

71a, 71c and 74:1, 740, triangular end panel 46 ot the spout would tend to dish in rather than popping out during opening of the container. If

sections

72b and 75b were used alone, the triangular end panel 46 would tend to pop out but would be restrained to some extent by the large quantity of paperboard in

panels

46, 47, 48, 51 and 52 located below the plane of

sections

72b and 75b. The utilization of sections 72a and 75a eliminates the foregoing problem by intersecting score line 27 at the midpoints between the pairs of

score lines

24, 25 and 26, 23, respectively.

Sections 720 and 750 prevent the bending of the

roof panels

28 and 31, 32 along

sections

72b and 75b from extending to score

lines

25 and 26 above the intersection of

score lines

25 and 26 with score line 16. Such bending of the roof panels would result in the opening between the intersection of the bends with

score lines

25 and 26 being less than the width of panel 46 at-that point, rendering it very ditficult to open the spout. If score lines 72 and 75 were used alone, including

sections

72a, 72b, 72c and 75a, 75b and 750, a natural break or bend would occur along imaginary line 73 reducing, it not eliminating, any snap action. The problem of the natural break along imaginary line 73 is particularly acute for the small size containers which utilize a lightweight paperboard stock.

In accordance with the invention, it has been found that effective snap action can be obtained for both large and small containers without encountering the foregoing problems by utilizing snap action score

lines comprising sections

71a, 71b, 71c, 72a, 72b, 72c and 74a, 74b, 740, 75a, 75b and 750 in combination.

Score sections

72b and 75b form the fulcrums for snapping panel 46 between a stable closed position and a stable open position.

Score sections

71b and 72b, and similarly 74b and 75b permit the formation of an I beam structure from the three sections of each roof panel during opening, as shown in FIGURE 4. This prevents the formation of any natural breaks along imaginary line 73 and provides rigid support for

fulcrum score sections

72b and 75b.

The container of FIGURE 1 can be opened by applying outward pressure against the fold-

back panels

47 and 48 to cause a separation of the bond between adjacent outer faces of

rib panels

51 and 52. The container at this stage is illustrated in FIGURE 3.

Roof panels

28 and 31, 32 have broken along

score lines

71 and 73, respectively. Pressure can then be applied against

panels

47, 51 and 48, 52 to move these panels toward the container, as shown in FIGURE 4. This movement causes

roof panels

28 and 31, 32 to break along

score lines

72 and 75 to form the I beam structure. Tape 61 is removed from the container to permit the lower portions of

panels

46, 47, and 48 to separate from the upper portions thereof along the weakened line of severance 60. Pressure can then be applied to the outer edges of

panels

47, 51 and 48, 52 to move these panels further toward the container. During this movement a point is reached at which panel 46 snaps from the recessed position below the plane of

score lines

25 and 26 to an open position above such plane. Subsequent release of the pressure against the outer edges of

panels

47, 51 and 48, 52 permits these panels to assume the stable open position illustrated in FIGURE 5. The container can then be closed by applying pressure against panel 46 to move it inwardly. At a point during such inward movement, panel 46 will experience the snap action and be returned to its stable closed position, similar to the position illustrated in FIGURE 3 except for the absence of tape 61.

While the invention has been illustrated with the presently preferred container employing weakened line of sev erance 60, it is applicable to other side open containers which do not utilize a weakened line of severance or which provide the weakened line of severance in a different location.

Reasonable variations and modifications are possible within the scope of the foregoing disclosure, the drawings and the appended claims to the invention.

I claim:

1. A gable top container of sheet material comprising a tubular body having four side walls, a bottom closure fixed to said body, a pair of opposed roof panels inclining toward each other and overlying the top of said body, a pair of opposed triangular end closure panels infolded between said roof panels from the opposite gable ends formed by the latter, first and second pairs of triangular fold-back panels, each pair of triangular fold-back panels being joined to the opposite sides of a respective one of said triangular end closure panels along fold lines which are in proximity with said roof panels, said fold-back panels being folded against the underside of said roof panels, a ridge panel surmounting each of said roof panels, a ridge panel surmounting each of said fold-back panels, each pair of ridge panels surmounting a pair of fold-back panels being hinged together at the apex of the contiguous end closure panel and being folded about such hinge joinder in face-to-face relation, between the ridge panels surmounting said roof panels, wherein the improvement comprises first and second score lines located in each of said pair of roof panels, each of said first and second score lines comprising first, second and third score sections, the second score section of each of said first and second score lines being substantially parallel to each other and to the plane of one of said triangular end closure panels, the second score section of each of said first score lines being positioned in the respective roof panel above said plane and the second score section of each of said second score lines being positioned in the respective roof panel below said plane, the third score section of each of said first and second score lines extending downwardly from the lower end of the corresponding second score section of said first and second score lines to the lower corner of the respective roof panel contiguous to said one of said triangular closure panels, the first score section of each of said first and second score lines extending upwardly from the upper end of the corresponding second score section of said first and second score lines to a point on the upper edge of the respective roof panel substantially at the intersection of said plane with said upper edge.

2. A container in accordance with claim 1 wherein said four side walls are of substantially equal width, the apexes of said pair of opposed triangular end closure panels are located substantially at the central area of the gable, and the point of intersection of said third score sections with the upper edge of the respective roof panel is substantially at the midpoint of said upper edge.

3. A container in accordance with claim 2 wherein the rectangular end closure panel formed by said one of said triangular end closure panels and its associated pair of triangular fold-back panels is provided with a weakened line of severance lying solely within the upper portion thereof below the respective surmounting rib panels and extending transversely of said rectangular end closure panel and terminating at its ends in spaced relation to the side edges of said rectangular end closure panel, said rectangular end closure panel having a coating of thermoplastic material permanently bonded on the exterior side thereof, a tape overlying the exterior side of said weakened line of severance, at least the surface of said tape confronting said rectangular end closure panel being formed of thermoplastic material heat-scalable to said thermoplastic coating on said rectangular end closure panel, said tape being bonded to the entire marginal area of said rectangular end closure panel about said weakened line of severance by the heat sealing of said thermoplastic materials.

4. A paperboard blank for forming a container of rectangular formation and having a gable top, said blank being formed with laterally spaced-apart score lines extending vertically from the lower to the upper edge of the blank, a score line extending transversely of the blank in downward spaced relation to the upper edge thereof, said latter score line, in conjunction with said vertically extending score lines, defining opposed front and rear side wall panels and opposed end wall panels, a second transversely extending score line arranged intermediate the upper edge of said blank and said first transversely extending score line and defining, in conjunction therewith, and with said vertically extending score lines, a front roof panel surmounting said front side wall panel, a rear roof panel surmounting said rear side wall panel, and an area surmounting each of said end wall panels, each of said areas being provided with converging score lines inclining upwardly from said first transverse score line to said second transverse score line and defining in each of said areas a triangular end closure panel and a pair of triangular foldback panels hinged to the triangular end closure panel, said second transversely extending score line, in conjunction with said vertically extending score lines, defining ridge panels surmounting said front and rear roof panels and each pair of said fold-back panels, wherein the improvement comprises first and second score lines located in each of said roof panels, each of said first and second score lines comprising first, second and third score sections, the second score section of each of said first and second score lines being substantially parallel to each other and to the plane of one of said triangular end closure panels when folded and sealed to form a gable top container, the second score section of each of said first score lines being positioned in the respective roof panel above said plane and the second score section of each of said second score lines being positioned in the respective roof panel below said plane, the third score section of each of said first and second score lines extending downwardly from the lower end of the corresponding second score section of said first and second score lines to the lower corner of the respective roof panel contiguous to said one of said triangular end closure panels, the first score section of each of said first and second score lines extending upwardly from the upper end of the corresponding second score section of said first and second score lines to a point on the upper edge of the respective roof panel substantially at the intersection of said plane with said upper edge.

5. A blank in accordance with claim 4 wherein said front and rear side wall panels and opposed end wall panels are of substantially equal width, and the point of intersection of said third score sections with the upper edge of the respective roof panel is substantially at the midpoint of said upper edge.

6. A blank in accordance with claim 5 wherein the rectangular end closure panel formed by one of the triangular end closure panels and its associated pair of triangular fold-back panels is provided with a weakened line of severance lying solely within the upper portion thereof below the respective surmounting rib panels and extending transversely of said rectangular end closure panel and terminating at its ends in spaced relation to the side edges of said rectangular end closure panel, said rectangular end closure panel having a coating of thermoplastic material permanently bonded on the exterior side thereof.

References Cited UNITED STATES PATENTS 3,185,375 5/1965 Thomas 229-l7 3,204,850 9/1965 Wilcox 229-47 3,295,739 1/1967 Wilcox 229-17 JOSEPH R. LECLAIR, Primary Examiner.

20 D. M. BOCKENEK, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,348,755 October 24, 1967 George E. MacEwen 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.

Column 6, line 8, "triangular" should read triangular end Column 8, after line 11, insert 7. A blank in accordance with claim 6 further comprising a tape overlying the exterior side of said weakened line of severance, at least the surface of said tape confronting said rectangular end closure panel being formed of thermoplastic material heat-sealable to said thermoplastic coating on said rectangular end closure panel, said tape being bonded to the entire marginal area of said rectangular end closure panel about said weakened line of severance by the heat sealing of said thermoplastic materials.

In the heading to the printed specification, line 6, "6 Claims" should read 7 Claims Signed and sealed this 11th day of November 1969.

(SEAL) Attest I EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents

Claims

1. A GABLE TOP CONTAINER OF SHEET MATERIAL COMPRISING A TUBULAR BODY HAVING FOUR SIDE WALLS, A BOTTOM CLOSURE FIXED TO SAID BODY, A PAIR OF OPPOSED ROOF PANELS INCLINING TOWARD EACH OTHER AND OVERLYING THE TOP OF SAID BODY, A PAIR OF OPPOSED TRIANGULAR END CLOSURE PANELS INFOLDED BETWEEN SAID ROOF PANELS FROM THE OPPOSITE GABLE ENDS FORMED BY THE LATTER, FIRST AND SECOND PAIRS OF TRIANGULAR FOLD-BACK PANLES, EACH PAIR OF TRIANGULAR FOLD-BACK PANELS BEING JOINED TO THE OPPOSITE SIDES OF A RESPECTIVE ONE OF SAID TRIANGULAR END CLOSURE PANELS ALONG FOLD LINES WHICH ARE IN PROXIMITY WITH SAID ROOF PANELS, SAID FOLD-BACK PANELS BRING FOLDED AGAINST THE UNDERSIDE OF SAID ROOF PANELS, A RIDGE PANEL SURMOUNTING A PAIR OF FOLD-BACK RIDGE PANEL SURMOUNTING EACH OF SAID FOLD-BACK PANELS, EACH PAIR OF RIDGE PANELS SURMOUNTING A PAIR OF FOLD-BACK PANELS BEIGN HINGED TOGETHER AT THE APEX OF THE CONTIGUOUS END CLOSURE PANEL AND BEING FOLDED ABOUT SUCH HINGE JOINDER IN FACE-TO-FACE RELATION, BETWEEN THE RIDGE PANELS SURMOUNTING SAID ROOF PANELS, WHEREIN THE IMPROVEMENT COMPRISES FIRST AND SECOND SCORE LINE LOCATED IN EACH OF SAID PAIR OF ROOF PANELS, EACH OF SAID FIRST AND SECOND SCORE LINES COMPRISING FIRST, SECOND AND THRID SCORE SECTIONS, THE SECOND SCORE SECTION OF EACH OF SAID FIRST AND SECOND SCORE LINES BEING SUBSTANTIALLY PARALLEL TO EACH OTHER END TO THE PLANE OF ONE OF SAID TRIANGULAR END CLOSURE PANELS, THE SECOND SCORE SECTION OF EACH OF SAID FIRST SCORE LINES BEING POSITIONED IN THE RESPECTIVE ROOF PANEL ABOVE SAID PLANE AND THE SECOND SCORE SECTION OF EACH OF SAID SECOND SCORE LINES BEING POSITIONED IN THE RESPECTIVE ROOF PANEL BELOW SAID PLANE, THE THIRD SCORE SECTION OF EACH OF SAID FIRST AND SECOND SCORE LINES EXTENDING DOWNWARLDY FROM THE LOWER END OF THE CORRESPONDING SECOND SCORE SECTION OF SAID FIRST AN SECOND SCORE LINES TO THE LOWR CORNER OF THE RESPECTIVE ROOF PANEL CONTIGUOUS TO SAID ONE OF SAID TRIANGULAR CLOSURE PANELS, THE FIRST SCORE SECTION OF EACH OF SAID FIRST AND SECOND SCORE LINES EXTENDING UPWARDLY FROM THE UPPER END OF THE CORRESPONDING SECOND SCORE SECTION OF SAID FIRST AND SECOND SCORE LINES TO A POINT ON THE UPPER EDGE OF THE RESPECTIVE ROOF PANEL SUBSTANTIALLY AT THE INTERSECTION OF SAID PLANE WITH SAID UPPER EDGE.