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Claims  |
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I claim:
1. A joint comprising:
adjacent central webs presenting confronting first and second web edges,
a polysurfaced female lip adjoined to the first web edge and comprising, in
sequence, relative to the first central web edge:
an upwardly and inwardly extending first element,
an upwardly and outwardly extending second element,
an outwardly extending third element,
an outwardly and downwardly extending fourth element, and
a re-entrant terminal element;
a polysurfaced male lip adjoined to the second web edge and comprising:
an upwardly and outwardly extending first leg overlapping said first
element,
a re-entrant arcuate terminal leg engaged with said re-entrant terminal
element, and
said first leg and said terminal leg being joined by at least two distinct
legs and intermediate thereof at least one arcuate bend,
said arcuate bend being in engagement with an interior surface of said
female lip;
said male lip being interlocked with said female lip thereby to provide
said joint which secures the adjacent central webs in fixed angular
relation to each other.
2. The joint of claim 1 wherein the normal distance between the interior
surfaces of said fourth element and of said first element is at least less
than the maximum distance between the exterior surfaces of said re-entrant
arcuate terminal leg and the juncture of said first leg and the adjoining
one of said two distinct legs.
3. The joint of claim 1 including sealant material compressed between the
interior surface of at least said second element, and the exterior surface
of a confronting leg of said two distinct legs.
4. The joint of claim 1 wherein said arcuate bend engages said outwardly
extending third element.
5. The joint of claim 1 wherein said arcuate bend is laterally offset from
a plane extending normal to said third element and longitudinally through
the center of said joint.
6. The joint of claim 5 wherein said arcuate bend is remote from said
second element.
7. The joint of claim 5 wherein said two distinct legs are of different
widths.
8. The joint of claim 5 wherein said two distinct legs have substantially
equal widths.
9. The joint of claim 1 wherein the second and fourth elements converge
toward a line spaced above and generally parallel with said third element.
10. The joint of claim 9 wherein said line resides in a plane extending
normal to said third element and longitudinally through the center of said
joint.
11. The joint of claim 1 wherein said arcuate bend, the juncture between
said first leg and one of said two distinct legs, and said first leg of
said male lip engage interior surfaces of said female lip along three
distinct lines of contact which extend substantially the entire length of
said joint.
12. The panel of claim 1 including a bead of sealant material applied along
any line in a region of said female lip which includes the contiguous
interior surfaces of said first element, said second element and said
third element.
13. The panel of claim 12 wherein said region extends approximately from
the mid-line of said first element to the juncture of said second element
with said third element.
14. The panel of claim 1 including a bead of sealant material applied along
any line in a region of said female lip which includes the contiguous
interior surfaces of said first element and said second element.
15. The panel of claim 14 wherein said region extends approximately from
the mid-line of said first element to the mid-line of said second element.
16. A roof structure comprising plural roofing panels assembled in
side-by-side relation, supported on and secured to spaced-apart purlins,
and connected in interlocked relation by plural upstanding joints, each of
said joints comprising:
adjacent ones of said roofing panels having central webs presenting
confronting first and second web edges,
an upstanding polysurfaced female lip adjoined to the first web edge and
comprising:
a first element extending upwardly from and inwardly over the first web
edge,
a second element extending upwardly from and outwardly of said first
element,
a third element extending laterally outwardly from said second element and
beyond said first and second web edges,
a fourth element extending outwardly of and downwardly from said third
element, and
a re-entrant terminal element adjoined to said fourth element and spaced
above the central web of said first roofing panel; and
an upstanding polysurfaced male lip adjoined to the second web edge and
comprising:
a first leg extending upwardly from and outwardly of the second web edge
and overlapping said first element,
a re-entrant arcuate terminal leg engaged with said re-entrant terminal
element,
said first leg and said re-entrant arcuate terminal leg being joined by at
least two distinct legs and intermediate thereof at least one arcuate
bend,
said arcuate bend being in engagement with an interior surface of said
female lip;
said male lip being interlocked with said female lip thereby to secure
adjacent roofing panels in fixed relation to each other.
17. The roof structure of claim 16 wherein each of said joints includes
sealant material compressed between the interior surface of at least said
second element, and the exterior surface of a confronting one of said two
distinct legs.
18. An interlocking panel having a central web presenting a first web edge
and opposite thereto a second web edge, and complementary lips, one
adjoined to and extending along each said web edge, said complementary
lips comprising:
a polysurfaced female lip including, in sequence, relative to said first
web edge:
an upwardly and inwardly extending first element,
an upwardly and outwardly extending second element,
an outwardly extending third element,
an outwardly and downwardly extending fourth element, and
a re-entrant terminal element; and
a polysurfaced male lip including, in sequence, relative to said second web
edge:
an upwardly and outwardly extending first leg,
a re-entrant arcuate terminal leg disposed over and spaced from said
central web,
said first leg and said terminal leg being joined by at least two distinct
legs and intermediate thereof at least one arcuate bend,
said arcuate bend residing at a level above said terminal leg;
said lips being configured for snap-fit engagement with complementary lips
of adjacent ones of said panel thereby to secure the central webs thereof
in fixed angularly spaced-apart relation relative to each other.
19. The panel of claim 18 wherein the normal distance between the interior
surfaces of said fourth element and of said first element is at least less
than the maximum distance between the exterior surfaces of said re-entrant
arcuate terminal leg and of the juncture of said first leg and the
adjoining one of said two distinct legs.
20. The panel of claim 18 wherein said arcuate bend is laterally offset
from a plane extending normal to said central web and longitudinally
through the center of said male lip.
21. The panel of claim 20 wherein said arcuate bend is remote from said
first leg.
22. The panel of claim 20 wherein said two distinct legs are of different
widths.
23. The panel of claim 20 wherein said two distinct legs have substantially
equal widths.
24. The panel of claim 18 wherein the second and fourth elements converge
toward a line spaced above and generally parallel with said third element.
25. The panel of claim 24 wherein said line resides in a plane extending
normal to said third element and longitudinally through the center of said
female lip. |
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Claims  |
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Description  |
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to joints between elements, such as building panels,
and more particularly to polysurfaced male and female lips which are
interlocked to provide an upstanding joint.
2. Description of the Prior Art
The prior art discloses numerous examples of joints which secure together
adjacent sheet metal panels without the necessity of crimping or otherwise
deforming the elements of the joint. Typical examples include U.S. Pat.
Nos. 2,019,379 (ANDERSON); 3,127,962 (JAMES); 3,481,094 (TAYLOR);
3,511,011 (STRAUS).
The ANDERSON joint is particularly suited for use in connecting the slats
of a rolling metal curtain. When used in wall or roof structures, the male
lip may be partially disengaged from the female lip by loads applied at
locations adjacent to the male lip. The possible partial disengagement
precludes formation of a reliable weather-tight seal.
The JAMES joint avoids the partial disengagement problem by providing
tightly nested cylindrically-shaped connecting members. A lubricant must
be applied to the contacting surfaces of the connecting members to
facilitate interconnection. The cylindrically-shaped connecting members
have substantially identical girths and therefore appear to utilize more
material than is actually necessary.
The TAYLOR joint also attempts to avoid the partial disengagement problem
discussed above by providing an inwardly extending crimp on the female lip
which is engaged by the terminal edge of the male lip. Despite the
presence of the crimp, the male lip is still subject to deflection by
applied loads and degradation of the weather-tight seal.
The STRAUS joint utilizes intricately formed male and female lips of single
and double metal thickness, respectively. The female lip is particularly
subject to damage during packaging, shipment and erection. Such damage
would interfere with the interconnection of the lips and the formation of
a weather-tight seal.
SUMMARY OF THE INVENTION
The principal object of this invention is to provide an upstanding joint
structure useful in connecting elements, such as building panels.
Another object of this invention is to provide an upstanding joint
comprising polysurfaced male and female lips which are self-seating and
self-aligning thereby precluding vertical and lateral movement of either
lip relative to the other due to non-uniform loading.
A further object of this invention is to provide polysurfaced male and
female lips which are hooked together and then rotated relative to each
other, the lips undergoing a snap-fit during relative rotation whereby
counter-rotation and disengagement of either lip from the other is
resisted.
A still further object of this invention is to provide an upstanding joint
structure which effectively locks adjacent building panels together
without the use of supplemental fastening means and without the necessity
of subsequent seaming operations.
The present invention provides an upstanding joint for connecting adjacent
central webs which present confronting first and second web edges. The
joint comprises polysurfaced female and male lips adjoined, respectively,
to the first and second web edges.
The polysurfaced female lip comprises, in sequence, relative to the first
web edge: an upwardly and inwardly extending first element, an upwardly
and outwardly extending second element, an outwardly extending third
element, an outwardly and downwardly extending fourth element, and a
reentrant terminal element.
The polysurfaced male lip comprises, in sequence, relative to the second
web edge: an upwardly and outwardly extending first leg which overlaps the
first element, and a re-entrant arcuate terminal leg engaged with the
re-entrant terminal element. The first leg and the terminal leg are joined
by at least two distinct legs and intermediate thereof at least one
arcuate bend which is disposed in engagement with an interior surface of
the female lip.
The male lip is interlocked with the female lip thereby to provide the
present joint which secures the adjacent central webs in fixed angular
relation to each other.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a broken isometric view illustrating the polysurfaced male and
female lips which constitute the joint of this invention;
FIGS. 2 through 7 are fragmentary end views illustrating the sequence of
forming the joint of this invention;
FIGS. 8 and 9 are views similar to FIG. 7, illustrating alternative male
lip configurations;
FIG. 10 is a view similar to FIG. 7, illustrating alternative angular
relationships between the adjacent webs;
FIG. 11 is a fragmentary end view of the female lip illustrating ranges
within which the bead of sealant material may be applied;
FIGS. 12 and 13 are end views of adjacent panels positioned as in FIGS. 3
and 4, illustrating sealant material applied to the first element and
wiping thereof by the male lip;
FIG. 14 is a fragmentary end view of the joint formed by the panels of
FIGS. 12, 13;
FIGS. 15 and 16 are end views of adjacent panels positioned as in FIGS. 5
and 6, illustrating sealant material applied to the second element and
wiping thereof by the male lip;
FIG. 17 is a fragmentary end view of the joint formed by the panels of
FIGS. 15, 16;
FIG. 18 is a broken isometric view illustrating a roofing panel
incorporating the male and female lips of this invention; and
FIG. 19 is an end view of a roof structure assembled from a plurality of
the roofing panels of FIG. 18.
DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
FIG. 1 illustrates a fragment of a sheet metal panel 30 comprising a
central web 31 presenting opposite first and second web edges 32, 33; and
upstanding polysurfaced female and male lips 34, 35 adjoined,
respectively, to the first and second web edges 32, 33. The panel 30 may
be produced by roll forming operations from material having a thickness of
from 18 to 26 gage, that is, 0.0478 to 0.0179 inch (1.21 to 0.45
millimeters) depending on the intended use of the panel 30. For example,
for single skin wall or roof applications, the panel 30 may be formed from
materials having a thickness of from 18 to 22 gage, i.e., 0.0478 to 0.0299
inch (1.21 to 0.759 millimeter). Where the panel 30 comprises the outer
skin of a composite panel, such as a double-skin foam core panel, the
panel 30 may be formed from materials having a thickness of from 24 to 26
gage, i.e., 0.0239 to 0.0179 inch (0.607 to 0.455 millimeter). Suitable
materials for use in either of the above-identified applications include
sheet metal provided with a tough weather-resistant coating on one or both
surfaces, stainless steel, aluminum, copper, terne, and reinforced
plastics.
In general, the polysurfaced female lip 34 comprises, in sequence and
relative to the first web edge 32: an upwardly and inwardly extending
first element 36, an upwardly and outwardly extending second element 37,
an outwardly extending third element 38, an outwardly and downwardly
extending fourth element 39, and a re-entrant arcuate terminal element 40.
A bead 49 of sealant material is applied to an interior surface of the
female lip 34. As will hereinafter be explained, the bead 49 may be
applied along any line in a region of the female lip 34 which includes the
contiguous interior surfaces of the first through third elements 36, 37,
38; and preferably a region which includes the contiguous interior
surfaces of the first and second elements 36, 37. The bead 49 may, as
illustrated in FIG. 1, be applied at the juncture 48 of the second and
third elements 37, 38.
In general, the polysurfaced male lip 35 comprises relative to the second
web edge 33: an upwardly and outwardly extending first leg 41, and
laterally spaced therefrom a re-entrant arcuate terminal leg 42. The
terminal leg 42 is disposed over and spaced from the central web 31. The
first leg 41 and the terminal leg 42 are joined by at least two distinct
legs, that is a second leg 43 and a third leg 44, and intermediate thereof
at least one arcuate bend 45 which resides at a level above the terminal
leg 42. As will hereinafter be explained, the lips 34, 35 are configured
for snap-fit engagement with complementary lips of adjacent ones of the
panel 30 to secure the central webs thereof in fixed angularly
spaced-apart relation relative to each other.
The upper portion of the female lip 34 which is constituted by the second,
third and fourth elements 37, 38, 39 is symmetrical about a vertical plane
P extending normal to the third element 38 and longitudinally through the
center of the female lip 34. Also, the second and fourth elements 37, 39
converge toward a line L which is spaced above the third element 38 and
which resides in the plane P. The symmetry of the upper portion provides a
visual resemblance to stiffening ribs 46 (FIGS. 18, 19) formed in the
central web 31 of a roof panel 68.
In the preferred arrangement, the upper portion of the male lip 35
constituted by the second and third legs 43, 44 and the arcuate bend 45,
is unsymmetrical about the plane P. That is, the arcuate bend 45 is
laterally offset from the plane P and is remote from the juncture 50 of
the first and second legs 41, 43. As a result, the second leg 43 will
cooperate with the second and third elements 37, 38 of the female lip 34
to provide a pocket 67 (FIG. 7) for the bead 49 of sealant material.
The sheet metal panel 30 is roll formed from material having a selected
girth. The edge of the material corresponding to the re-entrant tip 53 of
the terminal element 40 is the control edge. Should the material exceed
the selected girth, the excess material appears in the male lip 35 as a
run-out flange shown in dotted lines at 54. The run-out flange 54 will not
interfere with the interconnection of the female and male lips 34, 35.
It will be observed in FIG. 1 that the first element 36 and the first leg
41 are inclined in the same direction and at angles 47 and 51,
respectively, relative to the plane P. The angle 51 of the first leg 41
may be equal to but preferably is less than the angle 47 of the first
element 36 so as to provide for roll forming tolerances. The first element
36 and the first leg 41 constitute--in the joint 61 (FIG. 7)--overlapping
members which coact with the other elements and legs of the lips 34, 35 to
resist vertical disengagement of either of the lips 34, 35 relative to the
other lip 35, 34 when the adjacent panels 30A, 30B are subjected to
non-uniform loading. That is, upward movement of the panel 30B is
resisted, in part, by the overlapping first leg 41, whereas downward
movement of the panel 30A is resisted, in part, by the underlapped first
element 36.
In accordance with this invention, the male lip 35 of one panel is
configured to provide a snap-fit engagement with the female lip 34 of an
adjacent panel. To fully understand the mechanics of the snap-fit
engagement, the spatial relationship of certain of the elements and
certain interior and exterior dimensions of the lips 34, 35 will be
explained with reference to FIG. 1.
In the male lip 35, it is essential that the uppermost surface of the
arcuate bend 45 be at a level above the juncture 50 and the re-entrant
arcuate terminal leg 42. Thus positioned, the arcuate bend 45 acts as a
cam element which forces the terminal leg 42 to slide relative to the
fourth leg 39 as will hereinafter be described.
The female lip 34 has an interior width indicated at 55, that is the
distance between the interior surface of the terminal element 40 and the
interior surface of the juncture 56 of the first and second elements 36,
37. The normal distance from the interior surface of the fourth element 39
to the interior surface of the first element 36 is represented by the
dashed dimension line 57. The male lip 35 has a maximum width indicated at
58, that is the distance between the exterior surfaces of the terminal leg
42 and the juncture 50. In accordance with the present invention, the
maximum width 58 of the male lip 35 is equal to or less than the maximum
interior width 55 of the female lip 34. In order to achieve the desired
snap-fit relation between the male and female lips 35, 34, the normal
distance 57 of the female lip 34 is less than the maximum width 58 of the
male lip 35.
In a commercial embodiment of the sheet metal panel 30, the female lip 34
has a height of 1.5 inches (38.1 millimeters), an interior width 55 of
1.45 inches (36.8 millimeters), and a normal distance 57 of 1.30 inches
(33.0 millimeters). The second and fourth elements 37, 39 have an angle of
convergance 72 of about 53.1 angular degrees. The male lip 35 has an
overall height H of 1.5 inches (38.1 millimeters) and a maximum width 58
of 1.42 inches (36.1 millimeters). The first distinct leg 43 has an angle
of inclination 73 of about 75.1 angular degrees relative to the plane P,
and the second distinct leg 44 has an angle of inclination 74 of 37.1
angular degrees relative to the plane P.
The sequence of forming the present joint 61 (FIG. 7) between two of the
building panels 30A, 30B is illustrated in FIGS. 2 through 7. A first
panel 30A (FIG. 2) is secured to support members 59 (only one visible). A
second panel 30B is installed by hooking the female lip 34 thereof over
the male lip 35 (FIG. 2); and then moving the second panel 30B laterally
(FIG. 3) until the re-entrant terminal leg 42 engages the interior
surfaces of the third and fourth elements 38, 39. It will be observed in
FIGS. 2 and 3 that the juncture 60 between the first element 36 and the
central web 31B may engage and slide over the first distinct leg 43 during
lateral movement of the second panel 30B.
The second panel 30B (FIG. 3) is rotated in a clockwise direction about the
male lip 35 until the arcuate bend 45 (FIG. 4) engages the interior
surface of the third element 38. As the panel 30B is rotated from the
position of FIG. 3 to that of FIG. 4, the first and third elements 36, 38
are spread apart by the juncture 50 and the terminal leg 42 of the male
lip 35. The normal distance 57 is increased, that is approaches the
maximum width 58 of the male lip 35. Once the arcuate bend 45 engages the
third element 38 and the panel 30B is rotated further in a clockwise
direction, the first, third and fourth elements 36, 38 and 39 are spread
apart by the cooperative action of the junction 50, the arcuate bend 45
and the terminal leg 42. The resulting three lines of contact (represented
by the triangles) preclude binding of the male lip 35 within the female
lip 34.
As the panel 30B is rotated from the position of FIG. 4 to that of FIG. 5,
the first and third elements 36, 39 are spread apart such that the normal
distance 57 equals that of the maximum width 58.
As the panel 30B is rotated from the position of FIG. 5 to that of FIG. 6,
the first and fourth elements 36, 39 move toward each other and the normal
distance 57 decreases. Thereafter, the second panel 30B is rotated to the
final installed position (FIG. 7). It will be observed in FIG. 7 that the
male lip 35 is interlocked with the female lip 34 to provide a joint 61
which secures the adjacent central webs 31A, 31B in fixed angular relation
to each other.
It will also be observed in FIGS. 2 through 6 that the bead 49 of sealant
material remains out of contact with the male lip. After the panel 30B is
rotated beyond the position illustrated in FIG. 6, the bead 49 engages the
exterior surface of the first distinct leg 43. In the joint 61 (FIG. 7)
the bead 49 of sealant material is compressed between the interior surface
of at least the second element 37 and the exterior surface of the first
distinct leg 43.
It will further be observed that as the panel 30B rotates from the position
of FIG. 3 to the final position of FIG. 7, the female lip 34 and the male
lip 35 are in line contact along three angularly spaced-apart lines
indicated by the triangles; and are in surface contact between the
terminal element 40 and the terminal leg 42 along the arcuate region 75.
The three line contacts and the surface contact are maintained throughout
the length of the joint 61. The arrangement is such that the male and
female lips 34, 35 are self-aligning and self-seating.
The bead 49 of sealant material must be so located within the female lip 34
that a weather-tight seal is assured. In accordance with this invention
the bead 49 may be applied, as illustrated in FIG. 11, along any line
residing substantially within a region 77 which includes the contiguous
interior surfaces 81, 82 and 83 of the first through third elements 36-38.
Specifically the region 77 extends approximately from the mid-line 79 of
the first element 36 to the juncture 48 of the second element 37 with
third element 38. In the preferred arrangement, the bead 49 may be applied
along any line residing substantially within a preferred region 78 which
includes the contiguous interior surfaces 81 and 82. Specifically, the
preferred region 78 extends approximately from the mid-line 79 of the
first element 36 to the mid-line 80 of the second element 37.
The bead 49 of sealant material may be applied along the mid-line 79 of the
first element 36 (FIG. 12). As the panel 30B is rotated clockwise, the
bead 49 engages the exterior surface 85 of the first distinct leg 43 (FIG.
13) and is spread thereby along the interior surface 81 of the first
element 36. It will be observed in the resulting joint 61' (FIG. 14) that
the sealant material 49 has been spread and is compressed between (a) the
contiguous interior surfaces 81, 82 of the female lip elements 36, 37 and
(b) the contiguous exterior surfaces 84, 85 of the male lip legs 41, 43.
The bead 49 of sealant material may also be applied along the mid-line 80
of the second element 37 (FIG. 15). As the panel 30B is rotated clockwise,
the bead 49 engages the exterior surface 85 of the first distinct leg 43
and is displaced thereby. It will be observed in the resulting joint 61"
(FIG. 17) that the sealant material is compressed between the interior
surface 82 of the female lip element 37 and the exterior surface 85 of the
male lip leg 43.
Where the bead 49 is provided along the juncture 48 (FIGS. 2-7), a
weather-tight seal can be formed provided the bead 49 does not contact the
arcuate bend 45 of the male lip 35. Such contact would cause a portion of
the bead 49 to be displaced away from the cavity 67 (FIG. 7); and the
amount of sealant remaining would be insufficient to form an adequate
weather-tight seal. Undesirable contact with the arcuate bend 45 can be
prevented if the female lip 34 is engaged with and rotated about the male
lip 35 in the manner illustrated in FIGS. 2 to 7.
Because of the possible occurrence of the above-described premature
"contact", the bead 49 preferably is provided along any line residing
substantially within the preferred region 78 (FIG. 11). It will be
observed in FIGS. 12, 13 and 15, 16 that displacement of the bead 49 by
the first distinct leg 43 is always toward the subsequently formed cavity
67 (FIGS. 14, 17) and not away from the cavity 67.
Alternative arrangements of the present joint are illustrated in FIGS. 8
through 10. Corresponding numerals will be employed to identify
corresponding parts heretofore described.
FIG. 8 illustrates an arrangement wherein the first and second distinct
legs 43', 44' of the male lip 35 are of substantially identical width and
the arcuate bend 45 is centered on the plane P.
FIG. 9 illustrates an arrangement wherein the first leg 41 and the terminal
leg 42 of the male lip 35" are joined by three distinct legs 62, 63 and 64
and intermediate thereof two arcuate bends 65 and 66.
The first leg 41 and terminal leg 42 may be connected by a plurality of
distinct legs and arcuate bends. However, to minimize the amount of girth
required to form the lips, it is preferred that the first and terminal
legs 41, 42 be connected by the two distinct legs 43, 44 and the single
arcuate bend 45. It is also preferred that the arcuate bend 45 be offset
from the plane P as illustrated in FIG. 1 so as (a) to maximize the size
of the sealant pocket 67 (FIG. 7); (b) to preclude undesirable contact of
the arcuate bend 45 with the bead 49 of sealant material during
interengagement of the lips 34, 35; and (c) to facilitate the
above-described cam function of the arcuate bend 45.
In FIG. 7, the joint 61 secures the adjacent central webs 31A, 31B in
coplanar relation. It should be evident that the angular relation of the
central webs 31A, 31B may, as illustrated in FIG. 10, be altered as
required. The only requirement is that the normal distance 71 between the
terminal leg 42 and the web 31A be sufficiently large to permit passage of
the terminal element 40 during interengagement of the lips 34, 35 as
illustrated in FIGS. 2 and 3.
FIG. 18 illustrates a roof panel 68 presenting the upstanding polysurfaced
female and male lips 34, 35 along the opposite edges of the central web
31. The central web 31 may be provided with any suitable profile which
enhances the structural and aesthetic characteristics of the roof panel
68. In FIG. 18, the central web 31 is provided with spaced-apart ribs
46--the upper portion of the female lip 34 having a visual resemblance to
the upper portion of the ribs 46. The roof panel 68 is adapted to span
across plural support members, such as the purlins 69. A plurality of the
roof panels 68 may be assembled, as shown in FIG. 19, in side-by-side
relation wherein the joints 61 of this invention connect adjacent roof
panels. Each of the roofing panels 68 is secured to the purlins 69 by
plural fasteners 70.
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Description  |
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