U.S. patent number 3,881,290 [Application Number 05/461,399] was granted by the patent office on 1975-05-06 for glazed impervious sheet assembly and method of glazing.
This patent grant is currently assigned to General Electric Company. Invention is credited to George J. Bouchey.
United States Patent |
3,881,290 |
Bouchey |
May 6, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
GLAZED IMPERVIOUS SHEET ASSEMBLY AND METHOD OF GLAZING
Abstract
Glazed, weathertight assemblies particularly adapted for use as
closures, e.g, windows, in wall openings comprise an exterior stop,
L-shaped in cross-section, framing the opening, a ridge of pressure
sensitive resilient tape framing the exterior stop, a toe bead of
silicone rubber around the outer periphery of the ridge of tape, an
impervious sheet member in weathertight engagement against the tape
and the toe bead of silicone rubber and an interior stop having a
resilient surface biased against the impervious sheet member,
framing the exterior stop and the impervious sheet member and
secured to the exterior stop. Also disclosed is a method for the
glazing of outside walls from the inside only, in which such a
weathertight assembly is produced.
Inventors: |
Bouchey; George J. (Troy,
NY) |
Assignee: |
General Electric Company
(Waterford, NY)
|
Family
ID: |
23832408 |
Appl.
No.: |
05/461,399 |
Filed: |
April 15, 1974 |
Current U.S.
Class: |
52/204.593;
52/204.591; 52/204.597; 52/745.15 |
Current CPC
Class: |
E06B
3/5814 (20130101); E06B 3/62 (20130101); E06B
2003/6285 (20130101); E06B 2003/6282 (20130101); E06B
2003/6223 (20130101) |
Current International
Class: |
E06B
3/62 (20060101); E06B 3/58 (20060101); E04b
001/66 (); E06b 001/04 () |
Field of
Search: |
;52/309,397,398,400,741,746 ;156/107 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Perham; Alfred C.
Attorney, Agent or Firm: Voss, Esq.; Donald J. Finnegan,
Jr., Esq.; George B. Hedman, Esq.; Edward A.
Claims
I claim:
1. A glazed, weathertight sheet assembly for a wall opening
comprising:
i. an exterior stop adapted to engage the marginal edges about an
opening in an outside wall, said stop being L-shaped in
cross-section, the vertical leg of said stop extending into the
opening and the horizontal leg of said exterior stop extending from
the wall toward the inside;
ii. a continuous ridge of resilient pressure sensitive tape affixed
to the inside face of the vertical leg of said exterior stop
adjacent to the inner periphery of said exterior stop, the inwardly
presented face of said tape being adapted to receive an impervious
sheet member;
iii. a toe bead of silicone rubber composition around the outer
periphery of the ridge of said resilient tape, said bead bridging
the tape edge and the inside face of the vertical leg of said
exterior stop;
iv. an impervious sheet member in full weathertight engagement
around its outwardly presented edge with the inwardly presented
face of the ridge of resilient tape and the toe bead of said
silicone composition; and
v. an interior stop framing the exterior stop and the impervious
sheet member, said interior stop being affixed to the exterior stop
and having a resilient surface biased against the impervious sheet
member so as to prevent inward displacement of said member from
said opening and to maintain its position in said opening.
2. An assembly as defined in claim 1 which also includes an
interior bead of silicone rubber composition around the inner
periphery of the interior stop, said bead bridging the edge of the
interior stop and the inside face of the impervious sheet
member.
3. An assembly as defined in claim 1 wherein the impervious sheet
member is a light admitting member.
4. An assembly as defined in claim 3 wherein the light admitting
member comprises glass.
5. An assembly as defined in claim 3 wherein the light admitting
member comprises laminated glass having a resinous interlayer.
6. An assembly as defined in claim 5 wherein said light admitting
member comprises a sandwich of outer layers of glass with an
aromatic polycarbonate resin interlayer.
7. An assembly as defined in claim 3 wherein the light admitting
member comprises plastic and said ridge of resilient tape is at
least about one-sixteenth inch in thickness (after
compression).
8. An assembly as defined in claim 7 wherein the light admitting
member comprises an acrylic resin.
9. An assembly as defined in claim 8 wherein the light admitting
member comprises an aromatic polycarbonate resin.
10. A method for the weathertight installation from the inside of
an impervious sheet member into an opening in an outside wall, said
method comprising:
i. providing said opening with a continuous exterior stop, L-shaped
in cross-section, the vertical leg of said exterior stop extending
into the opening and the horizontal leg of said exterior stop
extending from the wall toward the inside;
ii. framing said exterior stop with a continuous ridge of resilient
tape having an inwardly presented impervious sheet member-receiving
face by affixing a resilient pressure sensitive tape to the inside
face of the vertical leg of said exterior stop adjacent to the
inner periphery of said exterior stop, the inwardly presented face
of said tape having a superjacent releasible protective sheet
backing, and then removing said protective sheet backing;
iii. applying a toe bead of a curable silicone rubber composition
around the outer periphery of the ridge of resilient tape said bead
bridging the tape edge and the inside face of the vertical leg of
said exterior stop;
iv. setting said impervious sheet member into the opening from the
inside and driving said impervious sheet member into full
weathertight engagement around its outwardly presented edge with
the inwardly presented pressure sensitive face of the ridge of
resilient tape and the toe bead of said silicone composition;
and
v. framing the exterior stop and the impervious sheet member with
an interior stop, said interior stop being affixed to the exterior
stop and having a resilient surface biased against the impervious
sheet member so as to prevent inward displacement of said member
from said opening and to maintain its position in said opening.
11. A method as defined in claim 8 including the step of applying
an interior bead of silicone rubber composition around the inner
periphery of the interior stop, said bead bridging the edge of the
interior stop and the inside face of the impervious sheet member.
Description
The present invention relates to glazed, weathertight impervious
sheet assemblies, comprising windows, opaque sheets, such as
spandrel glass or metal or plastic panels which, depending on the
material, function to admit light and/or to provide resistance to
the passage therethrough of moisture, air, gases, and selective
resistance to some forms of radiant energy, and the like. Also
comptemplated are methods for the installation of such sheets into
outside walls from the inside only.
BACKGROUND OF THE INVENTION
Most conventional methods of glazing openings in outside walls in
low, medium and high rise construction contemplate the installation
of the impervious sheet members, e.g., glass, plastic, glazing
panels, etc., from the outside into the framed opening. This
necessitates, especially in high rise construction, expensive
staging. Even if the glazing is accomplished by fitting the sheet
member from the inside, to insure weathertightness, it has usually
been necessary to install a final cap bead from the outside, which,
with high rise construction, also requires staging. Such beads are
also exposed to the weather and temperature changes which
accelerate deterioration.
The present invention provides improved weathertight assemblies in
which the sheet members comprise glass, plastic, metal, etc.,
without the need for an externally applied seal. The present
invention also provides a method of glazing in which such
assemblies are produced entirely from the interior side of the
wall. The method uses a toe bead of sealant which is not exposed to
the weather. Moreover, an integral compression gasket on the inner
stop eliminates the need to install a full perimeter shim, as in
some glazing methods. Non-light admitting sheet members or panels
can also be glazed.
As will be seen from the data hereinafter, weather-tightness of the
assemblies according to this invention is evidenced by compliance
with the NAAMM standards for water penetration under load at 30
pounds per square foot. Other advantages will be seen after
consideration of the following detailed description.
DESCRIPTION OF THE DRAWINGS.
In the accompanying drawings:
FIGS. 1 and 2 are perspective views, the former exploded, of a
weathertight assembly of the present invention, the latter showing
its supporting structure in phantom;
FIGS. 3 - 6 are fragmentary perspective end views, illustrating the
steps used in glazing an opening in a wall from the inside,
according to the present invention;
FIG. 7 is a cross-sectional view of a seal assembly to be
described, using a laminated glass (or an insulating glass, glass
plastic laminate, etc.), light admitting member and a compression
gasket as part of the interior stop;
FIG. 8 is a modification of a seal assembly as shown in FIG. 7
which includes an interior sealant bead; and
FIG. 9 is a cross-sectional view of a seal assembly to be
described, using a plastic light admitting means and a spline or
compression gasket as part of the interior stop.
DESCRIPTION OF THE INVENTION
In accordance with the present invention, there is provided a
glazed weathertight impervious sheet assembly for a wall opening
comprising:
i. an exterior stop adapted to engage the marginal edges about an
opening in an outside wall, the stop being L-shaped in
cross-section, the vertical leg of the stop extending into the
opening and the horizontal leg of the exterior stop extending from
the wall toward the inside;
ii. a continuous ridge of resilient pressure sensitive tape affixed
to the inside face of the vertical leg of the interior stop
adjacent to the inner periphery of the exterior stop, the inwardly
presented face of the tape being adapted to receive an impervious
sheet member;
iii. a toe bead of silicone rubber composition around the outer
periphery of the ridge of the resilient tape, the bead bridging the
tape edge and the inside face of the vertical leg of the exterior
stop;
iv. an impervious sheet member in full weathertight engagement
around its outwardly presented edge with the inwardly presented
face of the ridge of resilient tape and the toe bead of the
silicone composition; and
v. an interior stop framing the exterior stop and the impervious
sheet member, the interior stop being affixed to the exterior stop
and having a resilient surface biased against the impervious sheet
member so as to prevent inward displacement of the member from the
opening.
The assemblies of this invention permit the "wet" seal to be placed
closer to the weather as a toe bead, providing a greater degree of
watertightness than possible with a heel bead. The toe bead
eliminates any possibility of water entering the glazing channel
and pooling in front of the impervious sheet. Resilient tapes and
silicone rubber beads as used herein are not temperature sensitive,
and there is no need to delay construction while waiting for the
materials to become fluid and resilient enough for glazing.
Moreover, the assembly operation may be carried out with little
fear of breakage as may be the case with sealants which harden as
the temperature decreases, e.g., acrylic, vinyl acrylic or
polysulfide, and the like.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, FIGS. 1 and 2 show and assembly for
installation in outside wall 2, having outer surface 4 and inner
surface 6. Exterior stop 8 is substantially L-shaped in
cross-section, vertical leg 10 of the stop extending into the
opening and horizontal leg 12 extending from wall 2 toward the
inside. Resilient tape 14 is in the form of a compressed continuous
ridge affixed to the inside face of vertical leg 10. Toe bead 16 of
silicone rubber is disposed at the outer periphery of resilient
tape 14 and bridges the tape and vertical leg 10 of exterior stop
8. Impervious sheet member 18, of glass or plastic (metal or the
like can also be used) is in weathertight engagement with tape
ridge 14 and toe bead 16. Interior stop 20 is fixed to horizontal
leg 12 of exterior stop 8 by being engaged in detents or by being
affixed with screws (not shown) and it has an intergral
formed-to-fit resilient face comprising, for example, compression
gasket 22, which bears against impervious sheet member 18 and holds
it in position, e.g., during and after cure. Tape 14 and sealant 16
are compressed to about 25-75%, preferably 25-50%, of the tape
thickness with spacers or shims, as necessary.
The following description of the glazing method of this invention
can be best understood by referring to FIGS. 3 through 5,
inclusive, which show the stepwise installation of glass or a
similar impervious sheet material into an exterior stop framing an
opening. The exterior stop 8 and sheet 18 should be inspected to
determine that they meet conventional construction requirements for
proper and uniform face and edge clearances. The framed opening
should be square and plumb. It is desirable to seal any miter and
butt joints with a silicone rubber sealant prior to beginning the
installation steps. All weeps, or drain holes, should be located
and noted to prevent plugging or inadvertent sealing during
glazing.
All glass, metal and plastic surfaces to which the tape and
sealants are to be applied should be cleaned, with methyl ethyl
ketone solvent on glass and metal surfaces; and isopropyl alcohol
or naphtha on plastic surfaces.
Continuous ridge 14 of resilient tape is formed by applying
pressure-sensitive tape from a roll against the horizontal head and
sill parts of exterior stop 8. The tape should not be pre-cut into
strips, and flexible sheet backing 15 should not be stripped before
installation as this may cause stretching of the tape. The tape
should be aligned evenly at the sight line. Then tape is affixed to
the vertical portions of exterior stop 8, butting the tape ends
against the head and sill portions of the tape. Release sheet 15 is
then removed to expose a clean, impervious sheet member-receiving
surface. The corners of the tape should not be lapped as this can
create voids. Although the corners can be "turned" by running a
continuous strip of tape around the opening, it is preferred not to
do so as the tape may be dislodged during the glazing sequence. It
is preferred to butter any tape butt joints with a silicone rubber
sealant. The width of the tape should be sized to allow a 1/4inch
(6.4 mm.) space between the tape and the sheet edge for placement
of toe bead 16. In accordance with conventional techniques, place
setting blocks on the sill portion of exterior stop 8 at the
quarter points from each corner or as desired. Spacers or spacer
shims (not shown) should also be installed to allow the tape and
sealant to be compressed to 25-75%, preferably 25-50%, of the tape
thickness. Then full toe bead 15 of a silicone rubber composition
is applied around the perimeter of tape 14, bridging the edge of
the tape and the inside surface of exterior stop 8 (FIG. 4).
Impervious sheet member 18 is set on the setting blocks (usually
not used if plastic is being glazed), the edges are aligned and the
sheet member is firmly driven against tape ridge 14 and toe bead
16. The excess bead of sealant is smoothed and compressed to obtain
continuous contact between the members and eliminate sealant voids
(FIG. 5).
To complete the installation, interior stop 20 is snapped into the
detents on horizontal leg 12 of exterior stop 8. Compression gasket
22 which is keyed into stop 20 bears against impervious sheet
member 18 to prevent lateral displacement and to maintain its
position (FIG. 6).
The glazing process of this invention is compatible with glass,
including laminated glass having a resinous interlayer, such as
polyvinyl butyral. FIG. 7 illustrates an assembly adapted for
laminated glass sheet 18, the assembly comprising exterior stop 8,
tape ridge 14, toe bead 16, interior stop 20 and compression gasket
22. FIG. 8 illustrates another assembly adapted for laminated sheet
glass 18, the assembly comprising exterior stop 8, tape ridge 14,
toe bead 16, interior stop 20 and compression gasket 22. It also
includes optional interior bead 24, which is preferably a silicone
sealant composition. Preferred light admitting members are
sandwiches of glass with an aromatic polycarbonate resin
interlayer, e.g., LEXGUARD, a product of General Electric Company,
Pittsfield, Mass.
The glazing process of this invention is compatible with all
plastic glazing systems, such as acrylic resin sheets, styrene
plastic sheets, aromatic polycarbonate resin sheets, and the like.
FIG. 9 shows an assembly adapted for plastic sheet 18, the assemby
comprising exterior stop 8, tape ridge 14, which should be at least
1/16 inch thick (after compression), toe bead 16, interior stop 20
and compression gasket 22. Metal sheets as well as other impervious
sheets used for glazing purposes can all be used.
The present assemblies are superior to prior art systems because
there are no solvents or other volatiles to attack the sealants
used to seal insulating sheet members, affect the resinous
interlayers in laminated glass, or cause stress crazing in acrylic
sheets or polycarbonate sheets. Moreover, even if water should
accidentally gain entrance into any glazing channel, because the
critical seals are made of silicone rubber, the presence of water
will not cause deterioration or failure.
The pressure sensitive tapes used in the present methods and
assemblies can be prepared by techniques well known to those
skilled in the art.
Typical properties of a useful tape are as follows:
Property Value Test Method
__________________________________________________________________________
density, lbs./ft..sup.3 10 ASTM D-1667 hardness, (Shore 00) 32 ASTM
D-2240 force to compress, 30%,psi. 4.9 ASTM D-1667 compression
deflection 30%,psi. 2.6 ASTM D-1667 compression set (% loss from
orig. height) 7 90.degree. peel adhesion (ozs./m. width) 24 PSTC
1-A water absorption,% vol.max. 2 recommended application
temperature, .degree.C. 1-52 service temperature, .degree.C. -21 +
71 weathering Excellent (2000 hrs. in Atlas XW-WR Carbon Arc) 102
minutes -18 in. from water, 19 inches from arc. shelf-life 1 year
80.degree.F. max storage temperature
__________________________________________________________________________
"ASTM" refers to an American Society of Testing Materials Test.
"PSTC" is a test method of the Pressure Sensitive Tape Council.
The tapes can be made by casting onto a non-adhesive paper liner a
suitable weather- and water-resistant flexible foam of rubber or
plastic, such as a plasticized poly (vinyl chloride) foam of 5 to
20 lbs./cubic ft. density, in thickness of about 1/4 inch or 3/8
inch. Then a weather- and water-resistant adhesive comprising a
solvent solution of a natural or synthetic rubber or a resin, such
as an acrylate resin or a silicone resin, or the like is cast onto
the foam base. Evaporation of the solvent under conventional
conditions deposits a layer about 1-3 mils thick of adhesive on the
foam base. Then, the adhesive coated foam-paper composite is rolled
and is slit into ribbons, e.g., of 1/4 inch or 3/8 inch in width,
to provide tape in convenient rolls for storage and application.
Obviously, other methods can be used to prepare suitable tapes.
A suitable silicone-adhesive tape can be made as follows: a
pressure sensitive adhesive is obtained according to the procedure
disclosed in U.S. Pat. No. 2,857,356, incorporated herein by
reference, by intercondensing at about 140.degree.C. for 1-2 hours
a 65% xylene solution of a methylpolysiloxane resin having about
1.12 silicon-bonded methyl groups and chain-terminated with about
equal parts of hydroxy and isopropoxy groups, and having a
viscosity of about 12 centipoises as a 60% solids solution in
xylene, with a silanol end-stopped methylphenylpolysiloxane gum
having a viscosity of about 12 million centipoises and containing a
mole ratio of dimethylsiloxy groups to diphenylsiloxy groups of
95:5. The relative amount of resin to gum is about 1:1. The solids
content is then adjusted to about 60% solids in xylene, and about
1% by weight, based on solids of benzoyl peroxide catalyst is
added. The solution is cast on one of the major faces of a
plasticized poly (vinyl chloride) foam ribbon, density 10
lbs./ft..sup.3, 1/4 inch thick .times. 3/8 inch wide and the coated
ribbon, backed by a non-adhesive paper liner, is heated at about
140.degree.C. for 10 minutes to evaporate the solvent, and then
heated for 2 minutes at 175.degree.C. in a forced draft oven to
advance the cure. Such coating is pressure-sensitive and is 1 mil
thick. The composite is rolled, then split into tape rolls of
suitable widths, e.g., 1/4 to 3/8 inch.
The silicone rubber sealants used in the present methods and
assemblies can be prepared by techniques well known to those
skilled in the art.
Typical properties of a useful sealant, after curing for 21 days at
73.degree.F. and 50% relative humidity are as follows:
Property Value Test Method ______________________________________
hardness, (Shore A) 22 ASTM D-2240 tensile strength, 175 ASTM D-412
peel strength, 50 TT-S-001543* lbs./in. TT-S-00230 CGSB 19-GP-9**
tear strength, 25 ASTM D-624 lbs./in. dynamic movement capability,
% .+-.50 50% modulus, psi. 45 (1/2" .times. 1/2" bead) Extension at
1/2"/min. ultraviolet and 2000 hours twin-arc ozone resistance
Excellent and xenon Weathero- meter staining none TT-S-001543
tack-free time, hrs. 5 - 10 TT-S-001543 tooling time, min. 30 sag,
slump nil TT-S-001543 ______________________________________ * TT-S
-- National Bureau of Standards Test. ** CGSB -- Canadian
Government Specifications Board Test.
A suitable sealant can be applied from cartridges and is obtained
as follows: a base compound is prepared under anhydrous conditions,
comprising the following (by weight):
25,000 cps. viscosity silanol terminated polydimethyl- siloxane 100
parts dimethyldisiloxane treated fumed silica having a surface area
of approximately 200 m.sup.2 /g filler 10 do. stearic acid treated
calcium carbonate (filler) 125 do. 50 cs. methoxy terminated
dimethyl- disiloxane diphenyldisiloxane copolymer fluid containing
30 mole % diphenyldisiloxane 5 do. trimethylsilyl terminated 20 cs.
viscosity dimethyldisiloxane fluid 20 do.
A catalyst is prepared comprising (by weight):
methyltrimethoxysilane (cross- linker) 0.5 parts
1,3-dioxypropanetitanium-bis- ethyl acetoacetate (catalyst) 1.8 do.
1,3,5-tris-trimethoxysilyl- propylisocyanurate (adhesion promoter)
0.75 do.
One hundred parts of the base compound is mixed together with 3.05
parts of the catalyst mixture in the absence of air and atmospheric
moisture and then packaged in sealed applicator tubes. Other such
compositions are described in Smith and Hamilton, Ser. No. 282,337,
filed Aug. 21, 1972, now allowed, and in Weyenberg, U.S. Pat. No.
3,294,739 and 3,334,067, the disclosures of which are incorporated
herein by reference.
The water infiltration resistance of a glazed assembly prepared
according to this method is measure by testing, as follows:
A glazing sealant and a 1/4 inch .times. 1/4 inch glazing tape are
prepared as described above and used to glaze a fixed glass light
(1/4 inch thick, tempered) in a mill-finish aluminum frame with the
glass set from the interior. All surfaces to receive the sealant
are cleaned with methyl ethyl ketone. The glazing tape is applied
to the fixed stops, flush with the edges, with the corners tightly
butted. A full toe bead of silicone glazing sealant is applied to
the fixed stop against the glazing tape. The glass is installed
followed by application of the screwed on stops and interior
neoprene compression gasket, which compresses the glazing tape
about 60%.
The glazed frame is installed in a strong test chamber and
subjected to static pressure water tests in accordance with the
techniques required by the NAAMM Metal Curtain Wall Manual and by
ASTM-E 331- 70. The tests utilize a water spray at the rate of 5
gallons per hour per square foot (equal to rain at the rate of 8
inches per hour). The glazed unit is subjected to the static
pressures of water indicated, each pressure is maintained for 15
minutes, and the results are as follows:
Static Pressure Equivalent Wind (pounds per sq. ft.) Speed (MPH)*
Observation ______________________________________ 10 63 no leakage
20 90 no leakage 30 110 no leakage
______________________________________ * Per ASTM-E 283-68
The water- and weathertightness of the assembly according to this
invention is thus demonstrated.
While the preferred embodiments of this invention have been herein
illustrated and described, other obvious variations will suggest
themselves to those skilled in the art in the light of the above
detailed disclosure. The invention in all of its variations is
intended to be defined by the appended claims.
* * * * *