U.S. patent number RE30,432 [Application Number 05/879,797] was granted by the patent office on 1980-11-11 for structural assemblies.
Invention is credited to Richard L. Stoakes.
United States Patent |
RE30,432 |
Stoakes |
November 11, 1980 |
Structural assemblies
Abstract
A planar structural assembly has a series of cells formed by
elongate structural members, the cells each receiving a pane or
panel. To provide a weather-seal, closed loops of resilient sealing
strips extend around the exterior edge of each pane or panel and
are mounted on auxiliary members secured to the structural members.
The auxiliary members clamp the sealing strips in compression
against their panes or panels to ensure the seal there. The
contiguous edges of the sealing strips of adjacent cells are locked
in place and a seal formed between them by locking or zipper
strips.
Inventors: |
Stoakes; Richard L.
(Woldingham, Surrey, GB2) |
Family
ID: |
9719320 |
Appl.
No.: |
05/879,797 |
Filed: |
February 21, 1978 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
430036 |
Jan 2, 1974 |
03940897 |
Mar 2, 1976 |
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Foreign Application Priority Data
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Jan 10, 1973 [GB] |
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1285/73 |
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Current U.S.
Class: |
52/395; 52/464;
52/235; 52/772; 52/204.591 |
Current CPC
Class: |
E04B
2/60 (20130101); E04B 2/965 (20130101); E04B
2/765 (20130101); E04B 2/76 (20130101) |
Current International
Class: |
E04B
2/76 (20060101); E04B 2/88 (20060101); E04B
2/96 (20060101); E04B 2/58 (20060101); E04B
2/60 (20060101); E04B 002/88 (); E04B 001/00 () |
Field of
Search: |
;52/395,397,403,463,464,235,208,772,459 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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229350 |
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Sep 1956 |
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AU |
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1960395 |
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Jun 1971 |
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DE |
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2400954 |
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Jul 1974 |
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DE |
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958990 |
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Sep 1949 |
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FR |
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709039 |
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May 1954 |
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GB |
|
790903 |
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Feb 1958 |
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GB |
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Primary Examiner: Bell; J. Karl
Attorney, Agent or Firm: Hopgood, Calimafde, Kalil,
Blaustein & Lieberman
Claims
What I claim and desire to secure by Letters Patent is:
1. A structural assembly comprising, in combination, a frame
structure, a series of rigid elongate members being attached
together to form said structure and at least two contiguous spaces
being defined by the elongate member in the structure to receive
infill elements, and means making a seal between the members of
each each infill element, said means comprising a flexible sealing
device for each said space in the form of a closed loop of a
strip-like material engaging the infill element at the periphery of
the space, auxiliary rigid frame elements secured to the elongate
members clamping said sealing devices in place, at least at the
common boundary between each contiguous pair of said spaces, said
auxiliary elements comprising forward portions projecting laterally
oppositely away from a central portion, a recess being provided
between the front faces of the forward portions and each forward
portion having a respective flexible sealing device mounted on it,
a forward element of said sealing device covering the front face of
said forward portion and an inner marginal element of said sealing
device extending into said recess in a self-retaining manner, and
further, bridging sealing means being provided between the adjacent
edges of said inner marginal elements of the respective sealing
devices in said recess and lockingly securing the sealing devices
in the recess.
2. A structural assembly comprising, in combination, a frame
structure, a series of rigid elongate members being attached to
form said structure and a series of enclosed spaces being defined
by the elongate members in the structure each to receive an infill
element, said elongate member including at least one member
extending continuously over the extent of at least two contiguous
said spaces, means making a seal between the members and each
infill element, said means comprising an inner flexible sealing
device for each space in the form of a closed loop of a strip-like
material engaging the infill element at the periphery of the space,
respective auxiliary rigid frame elements for each side of said
space being secured to the elongate members forming said space and
projecting forwardly of their frame members, said auxiliary
elements clamping said sealing device in place, contiguous spaces
of said series having a common boundary being provided with
respective loop-form sealing devices that are clamped by a common
auxiliary frame element at said common boundary, said auxiliary
elements comprising forward portions projecting laterally
oppositely away from a central portion, a recess being provided
between the front faces of the forward portions and each forward
portion having a respective flexible sealing device mounted on it,
each said sealing device comprising a forward element covering said
front face and an inner marginal portion of said sealing device
extending from said forward element into said recess in a
self-retaining manner, and further, bridging sealing means being
provided between adjacent edges of said inner marginal portions of
the respective sealing devices in said recess and lockingly
securing the sealing devices in the recess.
3. A structural assembly according to claim 1 wherein rear sealing
members are provided behind said infill elements in opposition to
the loop-form sealing devices whereby to engage sealingly the edges
of each said infill element between a loop-form sealing device and
the associated rear sealing members.
4. A structural assembly according to claim 1 wherein said forward
portion of the auxiliary frame elements extend over the edges of
their associated infill elements and thereby to apply sealing
pressure to said edges.
5. A structural assembly according to claim 4 wherein each
loop-form sealing device comprises a portion disposed at the rear
of the forward portions of the auxiliary frame elements clamped in
compression between said forward portions and the associated infill
element.
6. A structural assembly according to claim 4 wherein rearward
projections are provided on said forward portions of the auxiliary
elements, the rearward projections being disposed intermediate the
lateral extent of said rearwardly disposed portions of the sealing
devices adapted to engage the infill element, said clamping
pressure being applied through said projections.
7. A structural assembly according to claim 4 wherein each
loop-form sealing device has a profiled rear face adapted to bear
on the infill element, the profile of the rear face providing a
plurality of laterally spaced lines of sealing the infill element
to extend substantially parallel to the associated edges of the
infill element, a marginal lip of said sealing device disposed
beyond the lateral extent of its engaging frame element forward
portion having a rear face profile providing one of said lines of
sealing.
8. A structural assembly according to claim 7 wherein said profile
includes an inner portion within the lateral extent of its engaging
frame element and providing a further of said lines of sealing, an
intermediate portion between said line of sealing of the lip
profile and said inner portion providing an additional line of
sealing but projecting rearwardly to a lesser extent than said lip
and inner portion before clamping pressure is applied.
9. A structural assembly according to claim 1 having a sandwich
infill in at least one cell of the frame structure, said infill
comprising two spaced infill elements overlying each other in
mutually parallel planes, said auxiliary frame elements extending
the depth of said sandwich infill between said parallel planes.
10. A structural assembly according to claim 1 having at least two
rigid elongate members directed transversely to each other and
junction means connecting together said elongate members permitting
relative movement of one of said members towards and away from the
other in the direction of the longitudinal axis of said one member,
each junction means providing relative location between said
secured members in a direction perpendicular to the plane in which
the longitudinal axes of the respective members lie.
11. A structural assembly according to claim 1 wherein the
auxiliary frame elements comprise a rearwardly directed web, a
forwardly open slot being provided in the elongate members to
receive said web in a freely fitting manner, openings being formed
in the auxiliary frame elements extending over the width of said
web and screws in said openings thereby projecting to engage
opposed inner faces of said forwardly open slot to secure the
auxiliary elements to the elongate members.
12. A structural assembly according to claim 11 wherein said
engagement of the screws with said slot inner faces permits
relative longitudinal displacement between the auxiliary frame
element and its associated elongate member. .Iadd. 13. A glazing
structure comprising an elongated structural member having two
spaced apart surfaces to abut against, with or without the
interposition of gaskets, the one faces of two panel edge portions
respectively, a glazing bead of open channel section whereof the
channel base is arranged to engage the structural member between
the said surfaces with the side walls of the channel extending
outwardly away from the structural member, the side walls being
turned outwardly from one another at their end portions to provide
abutments facing towards the surfaces to lie opposite the other
faces of the edge portions of the panels respectively, means
accessible from the outer side of the channel section of the
glazing bead to secure the base of the channel of the bead to the
structural member and two gaskets of elastomeric material each
having a first portion to lie between the abutment and the other
faces and second portions to enter within the channel of the
glazing bead, the arrangement being such that the glazing bead can
first be secured to the structural member with the first portions
of the gaskets secured between the bead and the panels to hold the
panels in position and the second portions can then be pressed side
by side in the channel to form a weatherproof seal for the channel.
.Iaddend. .Iadd. 14. A glazing structure as claimed in claim 13
wherein an additional panel is arranged parallel to and spaced
apart from the first panel and where the first portion of each
gasket lies between said abutment and the outside face of the
additional panel. .Iaddend.
Description
This invention relates to structural assemblies for buildings and
is particularly concerned with constructions in which an area is
filled using a pane or panel or a plurality of smaller panes (i.e.
transparent or translucent sheets) and/or panels mounted in a frame
structure.
According to one aspect of the invention there is provided a
structural assembly comprising a series of rigid elongate members
secured together to form a frame structure defining at least two
enclosed spaces arranged to receive infill elements panes or
panels, and means making a seal between the members and each said
pane or panel, said means comprising a flexible inner sealing
device for each said space in the form of a closed loop of a
strip-like material engaging the frame members at the periphery of
the space, and auxiliary rigid frame elements clamping said sealing
devices in place, further bridging sealing means being provided
between adjacent edges of respective sealing devices at the common
boundary or boundaries between each contiguous pair of said
spaces.
According to another aspect of the invention, there is provided a
structural assembly comprising a series of rigid elongated elements
secured together to form a frame structure defining at least one
enclosed space arranged to receive an infill pane or panel, and
means making a seal between the members and said pane or panel,
said means comprising an inner flexible sealing device for the
space in the form of a closed loop of a strip-like material
engaging the frame members at the periphery of the space and
auxiliary rigid frame elements clamping said sealing device in
place at least one peripheral flexible sealing device being
disposed outwardly of said loop-forming sealing device at the
external periphery of said frame structure, and further, bridging
sealing means being provided between adjacent edges of the or each
peripheral sealing device and the contiguous loop-form sealing
device or devices at the common boundary or boundaries between said
peripheral device and said loop-form device or devices.
Particularly when the assembly is relatively large it is preferable
to secure the frame members together in such a way that they are
free to make slight movements relative to each other, e.g. for
thermal expansion and for building movements.
In a preferred form of the invention, the or each said pane or
panel has its edges sealingly located between said loop-form
sealing devices and rear sealing members disposed in opposition to
said sealing devices. The auxiliary frame elements can comprise
forward portions projecting laterally from a central securing
portion, said forward portions being adapted to extend over the
edges of the or each associated pane or panel and thereby to apply
sealing pressure to said edges. This can conveniently be done by
arranging that said loop-form sealing devices locate on said
forward portions of the auxiliary elements to extend around at
least a part of the front and rear surfaces thereof, that portion
of each device at the rear of the forward portions being clamped in
compression against the associated pane or panel. A recess between
the front faces of said forward portions can provide a keying
engagement for the sealing devices.
Preferably said forward portions are provided with rearward
projections disposed intermediate the lateral extent of rear
portions of the sealing devices engaging the pane or panel, the
clamping pressure referred to above being applied through said
projections. Preferably also the rear faces of the sealing devices
bearing on the pane or panel are given a profile providing a
plurality of laterally spaced lines of sealing therewith, such that
said profile includes a marginal lip providing one of said lines of
sealing that is disposed beyond the lateral extent of said frame
element forward portion.
By way of example, the invention will be more particularly
described with reference to the accompanying drawings, wherein:
FIG. 1 is an exploded perspective view showing some of the
components at a mullion/transom junction in one embodiment of
structural assembly according to the invention,
FIG. 1a illustrates schematically the complete assembly,
FIG. 2 is a side view of the junction of FIG. 1,
FIG. 3 is a plan view of a part of the same structural assembly
showing the attachment of a transom to a mullion and of a mullion
to a lower sill,
FIG. 4 is a view in a horizontal plane of a part of the same
structural assembly at a jamb,
FIG. 4a shows a modification of the construction in FIG. 4 as seen
in the same horizontal plane,
FIG. 5 is a plan view showing a modification of the assembly of the
preceding figures to provide double glazing or a sandwich wall,
and
FIG. 6 is a further illustration of the modification in FIG. 5
showing how transition can be achieved between single and sandwich
panes or panels in successive cells of the structural assembly.
The drawing shows embodiments of the invention in which a frame
structure, as illustrated in FIG. 1, is composed of a series of
mullions 2 extending upwardly from a bottom cill member 6, and
connected by transoms 4, the opposite side edges of the structure
being formed by jamb mullions 8 and the upper edge of top sill
members 10. The sealing arrangements are similar for all the
members, as will be explained below, and detailed illustration of
only some of the members is all that is necessary for an
understanding of the invention.
Each mullion 2 comprises a main box section having relatively deep
side walls 12 joined by a front wall 14 and a rear wall 16. A
forwardly projecting channel-like formation 18 located centrally on
the front wall 14 is made up of a pair of parallel flanges 20 with
stiffening root fillets 22. In the slot 24 between the flanges 20,
central web 26 of an extruded generally T-form auxiliary frame
element 28 is a free fit. (Similar auxiliary frame members are
associated with the other members forming the frame structure and
co-operate with them in a similar manner.) The side limbs 30 of the
element 28 receive opposite-handed extruded sections 32a of
respective outer sealing gaskets 32 that, in conjunction with inner
sealing strips 33 mounted on flanges 34 of the mullion, seal the
edge of a pane or panel 36 clamped between them. The clamping
pressure is applied by the auxiliary frame element 28 and is
obtained by tightening countersunk screws 38 securing it to the
frame element, these passing through spaced apertures along the
length of the frame element and projecting laterally of the element
to be gripped by the opposed faces of the flanges 20.
The side limbs 30 of the T-form auxiliary element are profiled to
provide a recess 40 between them with re-entrant side faces and at
the edges of the limbs are rearwardly directed lips 42. The gaskets
32 are made of a resilient material and can initially be mounted on
the auxiliary elements 28 in a substantially undeformed state. Each
section 32 comprises a female region that generally fits its
associated side limb 30 but with some slight clearance at the
forward and outer regions 46 of the side limbs and also at the rear
regions 48 inwardly of the lips 42, where the element is forwardly
recessed, the purpose of which will be described below. Inner side
margin 50 can fit into one side of recess 40 of the auxiliary
element.
The rear face of each section 32a comprises an inner lobe 52
located slightly inwardly of the recess 48 on its associated frame
element side limb 30. An outer lobe 54 lies outwardly of the side
limb and in the unstrained state of the section projects rearwards
slightly more than the lobe 52. Between these two lobes,
approximately coincident laterally with the lip 42, is an auxiliary
ridge 56 shallower than either of the lobes.
Between the margins 50 of the two adjacent sections 32a in the
recess 40, there is a small gap 58 sufficient for both sections to
be assembled on the frame element 28 without interference with each
other. In the front of the gap 58, a profiled space between the two
sections is arranged to receive a zipper or locking strip 60 of a
material that is hard in relation to the material of the gaskets
32, but that it is also elastically deformable, to form a seal with
the juxtaposed sections. It is to be noted that the maximum width
of the zipper strip cross-section lies within the tapered sides of
the recess 40 so that the zipper strip cannot work loose when
inserted.
The zipper strip 60 is not inserted until after the gaskets 32 have
been clamped into sealing engagement with the panes or panels 36,
as will be described below. This clamping action is obtained by
tightening the screws 38 and has the effect of deforming the gasket
profile to bring both lobes 52, 54 and the ridge 56 into engagement
with the clamped pane or panel. In the tightening process the outer
lobe 54 of each section first engages the pane or panel and begins
to be flexed outwards, the clearance at 46 facilitating this
action. As said flexing begins, the inner lobe 52 engages the pane
or panel and after being urged more firmly into the recess 48 it
also begins to flex but inwards because of its location relative to
the relative to the recess 48. This deformation thus acts in
opposition to the outward flexing of the lobe 54 and intending to
draw the section inwards and under the frame element side limb 30
assists in preventing wrinkling of the front face of the section as
the outer lobe 54 is fully deformed.
When the edge of a pane or panel is clamped, the clamping pressure
is applied almost wholly through the lobe 52 directly from the
associated frame element side limb 30. The ridge 56, the function
of which is to provide an intermediate line seal, will bear with
little pressure because of its small size in relation to the lobe
52, while the lobe 54 is able to flex relatively freely as the
clamping pressure increases due to the fact that it is well beyond
the lateral extremity of the side limb 30. It will be noted thus
that the primary seal afforded by the lobe 54 is obtained
separately from the clamping effect afforded by the lobe 52 while
the greater the clamping pressure applied, the more firmly are the
sections 32 held in place on the side limbs 30.
In the use of the invention, e.g. for curtain walling, the various
components can be cut to size and preformed before they are brought
to the building site. The frame members and the auxiliary elements
will themselves be formed from extruded metal sections, the
elements 28 having holes drilled at intervals along their length to
receive the screws 38. The sealing gaskets will each be formed as a
closed loop: that is to say, the frame structure will itself be of
a cellular nature (in its simplest form each of the cells being of
rectangular form, e.g. as defined between adjacent lines of
mullions and transoms) and a sealing gasket will thus comprise
lengths of an extruded section having the cross-section illustrated
with specially moulded junction pieces having a similar
cross-section bonded to the ends of these lengths to join them in
the closed loop. A rectangular cell will then have a sealing gasket
in the form of a rectangular loop with the four lengths forming the
sides of the rectangle joined by relatively small L-pieces with
which they are integrally moulded.
The initial state of the assembly involves the erection of the main
members of the structure. The bottom sill member 6, is first
secured in place and exturded spigot members 62 are mounted on this
by screws 64 passing through a central slot 66 to locate the bottom
ends of the mullions and the jamb mullions. At the tops of the
mullions and jamb mullions, on their side faces, further spigot
members are provided to engage the top sill members 10 running
between adjacent pairs of these vertical members of the frame
structure. The transoms are similarly supported by spigot members
on the mullions and jamb mullions and the assembly of a transom is
shown in some detail in FIG. 1 where it will be seen that this
member comprises a main channel-form section 68 which can be simply
dropped onto the spigot members between which it runs, the bottom
face of the member then being closed by a snap-on capping 70. It is
to be noted that the spigot form connections allow relative
movements, e.g. of the transoms transversely to the mullions, that
can take up differential thermal expansion effects.
The inner sealing strips 33 can all be cut to length and mounted on
their flanges 34 of the frame members before assembly. At the
junctions between frame members, the sealing strips 33 are in
abutment with each other but there is special provision made at
these junction regions for the auxiliary frame element as will be
subsequently described.
To describe now the glazing or infill of the frame structure thus
erected it will be convenient to presume that the structure is in
the form of a rectangular grid i.e. comprising a number of vertical
columns side-by-side each column being made up of a series of cells
of rectangular form above each other, the mullions forming the
divisions between the successive columns and the transoms the
divisions between successive cells in each column.
The glazing or infill process is tackled column by column, starting
from the bottom of each. Thus, first the T-section auxiliary
element of the bottom cill member is secured loosely in place, and,
with the pane or panel supported on that element, the first transom
auxiliary element is in turn secured loosely over the top edge of
the pane or panel. At this stage, short lengths of the sections of
the sealing gasket material are provided at the central regions of
these upper and lower T-section elements to retain the pane or
panel more safely in these initial stages when it is not firmly
gripped around its periphery.
The next pane or panel in that column can now be supported on the
first transom auxiliary frame element and similarly be secured at
its upper edge by mounting the second transom auxiliary frame
element. This procedure is then repeated over the full height of
the column until the top edge of the uppermost pane or panel is
held by the upper cill auxiliary frame element, and a second column
of panes or panels immediately adjacent the first is similarly
mounted on the frame structure, building up from the bottom.
With the second column completed, auxiliary frame elements can be
secured loosely onto the mullion between the columns and similarly
a further series of mullion frame element can be attached with the
completion of each succeeding column. Of course, at the jamb
mullions, the auxiliary frame elements can be attached there and
the panes and panels in the column adjacent the jamb can be mounted
whether or not there is a further column in place.
To maintain integrity of sealing at the junction regions of the
frame members at the corner of each cell, special provisions are
employed and in the arrangement illustrated in FIG. 1, the extruded
T-section auxiliary frame elements 28 terminate a few inches short
of each junction and a specially cast T-section, exemplified by the
cruciform unit 76, is provided at the junction to make up the gap,
the limbs of the unit each have an identical cross-section to the
frame elements 28. Alternatively, it may be more convenient to make
up the junction joint from short lengths of the extruded T-section,
mitered as indicated at 76a to form respective arms 77 that are
individually attached to the frame members. Whichever method is
used, at the mullion/transom junction shown, the arms of the
cruciform unit or assembly have elongated apertures or slots 78 for
attaching screws 80 to secure the unit to the mullion and the
transoms.
The apertures are elongated to allow relative movement between the
unit and each transom and so avoid constraint of thermal stresses
between these members. It will be appreciated that the spigots 62
also allow such movements to take place. Although no movement is
required between the junction unit and the mullion, by forming all
four apertures as elongate slot errors of assembly are avoided. It
will be appreciated from the foregoing that, in the initial
assembly, some small gap will be left between the transom auxiliary
frame elements 28 and their adjacent arms of the junction unit but
that this precaution is not necessary for the auxiliary frame
elements on the mullion. Of course, at the outer margins of the
frame, further units of T- and L-section will serve similar
functions to the cruciform unit shown and where appropriate
allowance can be made at these junctions also for thermal
movements.
Once all the T-section frame elements are in place, the temporary
retaining lengths of sealing gasket sections can be removed,
preferably after the T-section junction units have been put in
place. The panes or panels are able to move because of the
looseness of attachment of the auxiliary frame lements, but they
cannot fall from the frame structure.
On each cell of the grid, the prefabricated retangular outer
sealing gaskets are now mounted but the inner side margin 50 of
each gasket is left out of the recesses 40 so that the heads of the
screws 38 remain exposed and the screws can then be tightened up to
make the seal between the gasket and the pane or panel in the
manner already described. These side margins of the gaskets can now
be slid into position in the recesses 40. By using a roller tool it
is possible to do this at the same time as the zipper strip 60 is
inserted. At the junction regions, e.g. on the cruciform T-section
unit 76, the mullion zipper strip can run continuously through the
region and the zipper strips of the two transoms can then abut this
first strip.
In order to ensure that the sealing gaskets have their front limbs
held firmly in the recesses 40 of the frame elements 28, to prevent
inward leakage of moisture by this route, the zipper strips are
arranged to apply a substantial compression force to these portions
of each gasket by cutting the zipper strips slightly over-length
and inserting the zipper strips under considerable longitudinal
compression. Initially the compressed strip will not extend the
length of the space provided for it but if it is ensured that it
can expand to relieve some of the compressive force in it,
preferably by first applying an anti-friction coating in the slot,
after assembly it will fill the space provided and so apply the
residual compression in it evenly to the full length of the gasket
on which it bears.
It will be appreciated that at each outer or peripheral edge of the
frame structure, the closed or loop-form gaskets there engage only
the inner limb of the auxiliary T-section elements. Along the outer
limbs of the T-section elements at the peripheral edge of the frame
structure, as for example at the jamb mullion 8 in FIG. 4, straight
lengths of gasket 32b having a section corresponding to the
closed-loop gaskets 32 extend the length of each side of the frame
to abut or to be boned to L-form corner pieces (not shown) made up
of the same section material. The lengths 32b have a free length
such that they are held in compression when assembled and they
engage outwardly extending flexible sealing strips 89 that project
from the frame structure to bear sealingly on the surrounding
aperture boundary A or other construction on which the frame
structure is mounted. It may be noted here that for simplicity the
jamb mullion section may be the same as the main transom section
68, although of course a capping is not used here. As an additional
protection, mastic 91 is injected behind the strip 89.
An alternative arrangement to that in FIG. 4 is shown in FIG. 4a.
This uses a modified T-section 128, that differs from the element
28 by having an extended outer limb 129 comprising a socket 131
gripping sealingly a length of gasket 132. The socket and the
gripped portion of the gasket have complementary ribbed surfaces
133 for secure engagement and the gasket also comprises an integral
extension 135 sealing against the edge of the aperture in the same
manner as the strip 89. The formation of the gasket 132 in other
ways, and in particular as regards its engagement in the forward
recess 40 of the element 128, it similar to that of the gasket
32.
In a modified arrangement of the junction regions of the frame
structure, the use of specially cast or moulded I-section junction
units can be avoided by mitering small lengths of the extruded
T-section material to build up the cruciform or other shape
required, these separate elements being secured in place with their
mitred ends abutting. In the mullion/transom junction of FIG. 1,
the elements of this junction assembly that extend along the
mullion would then be secured by screws through circular apertures
preventing longitudinal movement. The elements of the assembly
extending along the transoms would have the slotted apertures shown
in the cast junction unit 76 but there would also be circular
apertures immediately adjacent their mitred ends for screws that
are tapped into the flanges 34 of the mullion so that these
elements are held fixed relative to the elements on the
mullion.
As is the case with the cast unit, the main T-section elements of
the mullion can abut onto the shorter elements of the junction
assembly (although it is likely that the need for manufacturing
tolerances would require some slight clearance) but a definite
clearance is left between each main transom T-section and their
associated elements of the junction assembly.
As a further possibility, the main T-section elements can be
extended into the junction regions where they have their ends
mitred to leave only the small gaps required for thermal movements
of the transoms (and top cills). In this event, the gaps at the
mitred joints will normally require the presence of further sealing
material and this can be provided by thickening the section of the
sealing gaskets at their corner regions. To ensure that the sealing
material is applied firmly to the gaps, it is also desirable that
the zipper strips be fitted without any possibility of a
discontinuity at the junction region: for this purpose, the
sectional material of the zipper strip can be used to form an
integral junction unit, (i.e. a cruciform unit at the
mullion/transom junction) with short arms extending into all the
T-section elements meeting at that junction, these arms abutting
main zipper strip lengths running between successive junction
regions.
Preferably, in such a zipper strip unit the sectional form is
itself thickened at the corners where its arms meet, e.g. the arms
having radiussed fillets at the corners, in order to increase the
sealing pressure it applied to the corner regions of the gaskets
when they are pressed the gaps between the T-sections elements. As
already described, of course, the main lengths of zipper strip are
compressed when inserted and it is arranged that as they expand to
fill their slots they in turn apply compression to the zipper strip
units at the junctions.
FIG. 5 of the drawings illustrates the provision of a
double-glazing or sandwich infill in a structural assembly
according to the invention. The sections of the frame members can
be identical to those in the embodiment of FIGS. 1 to 3, although
there is shown here a rather narrower transom 4a with a
correspondingly smaller suspension spigot 62a. Modified auxiliary
frame elements 28a are provided which differ from the elements 28
of FIGS. 1 to 4 in that a substantially wider recess 40a is
provided between the side limbs 30. In other respects, however, the
elements 28 and 28a are identical.
To provide for the increased thickness of the infill the frame
members' section may be modified to have a corresponding deepened
front channel formation 18. For manufacturing reasons, however, it
may be preferred to build up the increased depth by using
supplementary sectional members 82 so that the elements 28a are
connected to the frame members through the supplementary sectional
members 82 which are interposed between said elements and the frame
members. The members 82 are extruded lengths of material,
substantially co-terminous with their respective frame elements.
Their sectional form comprises a rear central web 84, analogous to
the web 26 and similarly being slotted to receive securing screws
38a the heads of which bear on the root of a forward channel-like
formation 86 of the member 82 that is analogous to the formation 18
on each frame member. It will be clear therefore that the frame
elements 28a can in their turn be secured to the members 82 by the
screws 38 engaging the internal faces of the channel-like formation
86.
The members 82 can be secured in place on the frame members before
assembly of the frame begins and the infill with the supporting
frame elements can then be mounted in the same way as in the
first-described example. In order to take up the increased width of
the recess 40a, it is convenient to use a wider zipper strip 60a
rather than change the section 32a. The thickness of spacer element
88 between the panes or panels of the sandwich infill of course
determines that the elements 28a apply a sufficient clamping force
for secure sealing of the infill, and the wider spacing of the side
limbs 30 of the elements 28a, as compared with the spacing of these
limbs on the elements 28, ensures that the sealing lobes 54 engage
the infill panes or panels laterally inwardly of the spacer
elements 88.
If it is required to change from a sandwich infill to a single-skin
infill in the one structural assembly, the arrangement shown in
FIG. 6 indicates one way in which this may be done. The upper half
of this figure has the sandwich infill construction already
described with reference to FIG. 5 but the lower flange 34 of the
transom (and the adjacent flange 34 of the mullion) now carry
extruded lengths of an adaptor 90, which comprises a rear channel
portion 92 clipping onto the associated flange 34 and a forward
flange 94 identical to the flange 34, on which the sealing strip 33
is located to provide a sealing face that is effectively co-planar
with the front face of the spacer element 88. To prevent leakage
past the spacer elements 88, a resilient sealing strip 96 is
gripped between the edges of the sandwich infill and the
supplementary member 82. A similar provision would of course be
made at the edges of a structural assembly that had a sandwich
infill over its whole area.
It will be appreciated that many modifications are possible within
the scope of the invention. Thus, although a planar structural
assembly has been described, it is possible to employ the invention
with curved or multi-planar assemblies. Also, although for
simplicity a rectangular frame grid has been described, the frame
and its cells can have different forms and it is by no means
necessary for the cells to be similar in shape to each other. As
regards their size, the cells encompassed by individual closed-loop
sealing devices may extend over a number of storeys.
An assembly according to the invention can of course receive infill
panes and/or panels of a wide variety of forms. Opening window
lights or other ventilation means may be included, for example, and
illuminated panels.
It is a feature of the illustrated constructions that the
preparation of the individual parts of the frame structure can be
completed in controlled conditions away from the building site.
Once at the site, it is only necessary to put the parts in place
and secure them there. The weather tightness of the assembly is
ensured by the closed-loop form of the sealing strips 32 and the
way in which the locking or zipper strips seal the junctions
between the contiguous portions of adjacent strips.
* * * * *