BACKGROUND OF THE INVENTION
[0001] This invention relates to an arcuate wall as part of a revolving door, and more particularly
to arcuate sidewall members made at least partly of glass.
[0002] In order to make the entrances to buildings such as airports, hospitals, shops, administrative
buildings, etc. look more attractive, it is desirable to have door leaves and the
surrounding structure made from glass or with glass as a substantial part. An unimpeded
or only slightly impeded look through the door construction improves traffic flow
through the door by reducing the number of incidents where persons bump into one another
due to lack of visibility.
[0003] The arcuate side walls in revolving doors are usually made of panels of non-transparent
material such as stainless steel, or with annealed glass bent to a right cylindrical
shape. A transparent plastic with sufficient scratch hardness to withstand the effect
of the constantly passing sealing element (felt or brush) on the edges of each rotating
door leaf is not presently available.
[0004] The use of bent, annealed glass in a door construction results in a number of disadvantages
and problems.
[0005] The costs of manufacturing are high for bent glass in dimensions to be used and manufactured
in the relatively small number of pieces in question with the accuracy required. The
high cost of the mold for bending further tends to limit the number of door diameters
available, thus limiting the architectural freedom in designing an entrance.
[0006] A problem associated with the use of annealed glass is its tendency to break into
large fragments with dangerously sharp edges. For security reasons and because of
the improved strength thereof, tempered or laminated the bent glass in question has
led to reluctant acceptance of the use of annealed glass, and the attendant risk of
personal injury in the event of breakage. This risk may be reduced somewhat by use
of an increased thickness of the glass.
[0007] Another disadvantage of using bent annealed glass is the difficult transportation
and mounting of these heavy and voluminous (because of the arcuate shape) pieces of
glass. The handling of the panes entails a high breakage risk, adding substantially
to the final price of the product.
[0008] Earlier attempts to make use of flat pieces of glass in the curved walls in revolving
doors in order to make the use of tempered and laminated glass economically feasible
have failed, either because the suggested design did not permit smooth rotation of
the door; the sealing between the edges of the door leaves and the arcuate wall could
not be maintained throughout the passage; or because the view through the transparent
area was too narrow to be attractive and/or to have any effect in improving the traffic
flow through the door.
[0009] It is an object of the present invention to overcome economic and technical disadvantages
and problems related to earlier designs of transparent panels for arcuate walls forming
part of revolving doors.
SUMMARY
[0010] As herein described, there is provided an arcuate glass panel made of a number of
relatively high, narrow strips of flat glass. Each strip of glass is sufficiently
wide, and the joints between the strips are sufficiently narrow, to provide an acceptable
view, and the width of each strip is sufficiently narrow to enable a smooth rotation
of the central revolving door member and its door leaves, the latter having a felt,
brush or other edge sealing member in continuous contact with the surface of the glass
panel.
[0011] The high narrow strips of flat glass may comprise tempered or laminated glass.
[0012] In order to provide an airtight, arcuate panel without individually framing each
glass strip, it is preferred that each strip of glass be glued to its neighboring
strip(s) along the vertical, adjacent edges thereof.
[0013] The high, narrow strips of glass may,,before the mounting thereof, be sealed or joined
together by means of an elastic adhesive or sealer. By providing permanent elasticity
for the seals between the glass strips, it is possible to build up a large arcuate
wall panel or segment away form the mounting side, to transport this panel or segment
as a flat member, and to mount this member at the construction site by bending it
to the curve desired, as part of the mounting operation. This technique allows for
manufacturing of the seals or joints under optimal, controlled conditions in a factory
and at the same time allows for fast and therefore inexpensive mounting at the construction
site.
THE DRAWING
[0014] The foregoing and other features and advantages of the present invention will become
more apparent in the light of the following description and accompanying drawing,
which is a top cross-sectional view of a portion of an arcuate glass panel for a side
wall of a revolving door according to a preferred embodiment thereof.
DETAILED DESCRIPTION
[0015] According to a preferred embodiment of the invention, a glass panel 10 for one arcuate
wall for one side of a revolving door may have a radius of 210 cm., a height of the
door leaves or strips equal to 230 cm., and a non-transparent, 25 cm. high foot panel
in the arcuate side wall, made and mounted in the following way.
[0016] Preferably, each strip should be at least 3 inches wide but sufficiently wide so
that it subtends an angle in the horizontal plane, which is no greater than 10° as
measured from the axis of rotation of the revolving door. The difference in radial
distance from the axis of rotation to the center and to either edge of the strip should
not exceed 5 mm. Preferably, the subtended angle should not exceed 9°, and the aforementioned
difference in radial distance should not exceed 3 mm.
[0017] It has been found that the majority of the commerical available brush or felt sealing
means may be used for sealing between the edges of the door leaves in a revolving
door and the arcuate walls in the door according to the present invention, without
compromising the sealing effect and at the same time not producing such friction as
to introduce disturbing effects on the smoothness of rotation; and that such commercially
available sealing means can absorb changes in distance between the axis of rotation
and the curved wall of 3 to 4 mm. A few of the above- mentioned sealing means (brushes
and felts) can satisfactorily absorb 5 to 6 mm. variations.
[0018] In the production plant, two identical glass panels are provided, each measuring
169 x 205 cm. and assembled from 10 strips of glass, each 16.5 wide x 205 cm. high.
Each strip of glass is laminated from 3 layers of 4 mm. thick glass and 2 layers of
laminating, 0.76 mm. thick sheets of polyvinylbutyrate (PVB).
[0019] The glass strips are placed in a simple mold. The mold may be made of 4 mm. thick
plywood 180 x 220 cm., bent to a radius of curvature of approximately 210 cm., defined
by two 12 mm. wide, 15 cm. or more high beams cut out of plywood. The mold is lined
with a polyethylene (PE) sheet in order to prevent the sealer from sticking to the
mold. The glass strips are placed parallel to one another leaving a 4 mm. wide slot
therebetween. The nine slots are then filled with a clear silicone sealer and left
to cure to form flexible joints 12.
[0020] After curing of the silicone rubber, the glass panel is removed from the mold and
placed in a conventional flat glass transportation box or rack. A second glass panel
is now made the same way, and both elements thus manufactured are transported to the
mounting site.
[0021] At the mounting site, each glass panel is taken from the transportation unit and
placed in the awaiting frame 13 for bending each panel to the desired curve, and releasing
the joints 12 from the stresses applied to them during transportation.
[0022] After mounting the first and the second prefabricated glass panels 10, the joints
between the two panels and between each panel and the frame 13 are respectively sealed
in a conventional way.
[0023] In order to ensure an acceptable view through the arcuate side wall, it is necessary
that each strip of glass 11 have a minimum width of at least 12.5 cm. (5 inches)being
preferred. If the glass strips are too wide, a smooth rotation of the rotating body
is not possible, or the necessary tight seal between the arcuate wall and the edges
of the door leaves will be absent through part of the passage of the door.
[0024] In a revolving door with a diameter of 2000 mm., the maximum acceptable width of
the glass strips in the panels according to the invention is 17.5 cm., a width not
exceeding 15.5 cm.-being preferred. In a (motorized) revolving door having a diameter
of 4.80 meters, the maximum acceptable width of the glass strips in the panels according
to the invention is 310 mm., and the preferred width is 240 mm. or less.
[0025] Several modifications may be introduced in relation to the above-described, preferred
embodiment of the invention without departing from the idea and scope thereof, as
expressed in the appended claims.
[0026] For instance, it is possible to use tempered or even annealed glass instead of laminated
glass. It is possible to have the long edges of the glass strips ground to accurate
shape for fitting in the frame, and the glass mounted to the frame without sealer
or with a rigid adhesive; or the sealing of the joints between adjacent strips may
be carried out at the mounting site. Sealing of the panels with the strips of glass
placed in one plane, leaving the seals unstressed during transportation and stressed
when mounted, is another possible modification.
1. A glass panel in the shape of an arcuate stationary wall for a revolving door,
comprising a plurality of high, narrow generally rectangular strips of flat glass
with joints of a flexible sealer therebetween, each strip having a height corresponding
to the height of said panel and a width of at least three inches, each strip subtending
an angle not greater than 10° as measured from the axis of rotation of said door,
the difference in radial distance from said axis to the center and either edge of
said strip not exceeding 5 mm.
2. A glass panel according to claim 1, wherein the minimum width of each strip is
five inches, said angle is not greater than 9°, and said difference in radial distance
does not exceed 3 mm.
3. A glass panel according to claim 1, wherein said strips comprise tempered or laminated
glass.
4. A glass panel according to claims 1, 2 or 3, wherein said joints are airtight.
5. A glass panel according to claim 4, wherein said joints are resilient.
6. A process for manufacturing and mounting an arcuate glass panel for use as a stationary
side wall of a revolving door, said panel comprising a plurality of flat glass strips
interconnected by flexible joints of a sealer material, comprising the steps of:
arranging a plurality of elongated rectangular flat glass strips on a supporting surface,
with the long edges of said strips parallel to each other and adjacent long edges
thereof spaced apart by intervals corresponding with the width of said joints, said
supporting surface having non-sticking properties in relation to a flexible curable
sealer material;
sealing the gaps between said strips with said sealer material;
curing said sealer material to provide a panel having flexible joints between adjoining
ones of said strips;
moving said panel to a construction site therefor;
adjusting the curvature of said panel to a desired arcuate shape at said construction
site; and
subsequently securing said arcuate panel to a curved frame.
7. The process according to claim 6, wherein said supporting surface has a curvature
defining said arcuate shape, so that said joints have minimal internal stresses when
said panel is secured to said frame.