Note: Descriptions are shown in the official language in which they were submitted.
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SYSTEM AND METHOD FOR MODULAR
CONSTRUCTION OF A DOME STRUCTURE
AND ASSEMBLY COMPONENTS FOR FACILITATING SAME
BACKGROUND OF THE INVENTION
[0001] The invention relates to a system and method for creating a dome
structure and, more particularly, to a system and method enabling a simple,
modular
manufacture of a dome.
[0002] Dome structures, used for centuries by humankind, are noted for their
strength and stability as a result of double arch configurations that carry
and resist
loading in various directions. Wooden domes are highly earthquake and
hurricane
resistant, as dome shapes resist movement damage better than conventional
buildings
and wood structures are more flexible than concrete. Domes also provide unique
aesthetics inside and out, rich acoustics inside and considerable design
flexibility.
[0003] During the past 50 years, dome construction has largely taken the form
of
monolithic concrete structures or wooden geodesic structures, both of which
have
inherent drawbacks. A monolithic structure (such as concrete domes) generally
needs to be created completely on site. Due to the size and weight of such
structures,
transportation maybe difficult if not impossible. Moreover, in most cases
there is
little flexibility in design that is often limited in its size or
configuration and it may
take a long time to actually manufacture the structure. Concrete is not
ecologically
friendly. Geodesic structures produce an appearance that is multi-faceted that
cause
potential roof leakage. It is also less aesthetically pleasing than monolithic
structures.
[0004] Thus, there is a need in the art for a system and method for producing
an
aesthetically pleasing dome structure which can be easily manufactured, is
resistant
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to weather and is environmentally friendly. There is also a need for a system
that can
be shipped easily to different site location and easily and quickly assembled
on site
to provide versatile structures that meets the various needs.
SUMMARY OF THE INVENTION
[0005] Accordingly, it is an object of the present invention to provide a
method
and system that enables construction of dome-shaped structures rapidly,
easily, and
inexpensively.
[0006] Another object of the invention is realized in a method and system
which
involves the creation of a dome structure including by forming a plurality of
sections, each section including top and bottom plate structures comprising
top and
bottom plates, two top shoulder plates, two bottom shoulder plates, and a
plurality of
ribs disposed therebetween, the ribs and all plates having an arc-shaped,
cross-
section. The respective top and bottom plates, top shoulder plates, ribs and
bottom
shoulder plates are secured together and two of the sections or more are
placed
adjacent to one another to produce a first ring. This is based on the size of
sections
manufactured. The sections can be manufactured with any sizes to suit the
needs,
taking into consideration the transportation and the site assembly
requirements. A
second ring is formed atop the first ring by placing a number of sections
adjacent to
one another to produce the second ring atop the first ring, with the second
ring
having a cross-sectional area smaller than the cross-sectional area of the
first ring.
This could be different for an outward bulging dome shape. The height of rings
is
variable, as is the length of the sections.
[0007] Preferably, the dome sections are made of wood, although the use of
other materials is feasible. In accordance with various embodiments of the
invention, there may be seven ribs disposed between the top and bottom
shoulder
plates. The ribs in the second ring may be placed closer to one another than
the ribs
in the first ring. In general ribs are spaced at specific distance at the
bottom of each
section. This is determined by the designer. The most common spacing is 16
inches
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on center. The ribs may be spaced closer on the top of each section than the
bottom.
Also, while the rib spacing at the bottom is generally the same throughout the
sections (the entire dome), the spacing at the top of the section gets smaller
the
higher the location of the section on the dome. This provides the required
dome
shape or configuration. This is the other way around in case of an outward
dome
shape or the inside of a donut shaped structure. Strapping and sheeting may be
provided to the exterior of the rings to provide a finished look. Preferably,
the
strapping is applied on the exterior in one or several layers and on the
inside in one
layer. Insulation may be disposed in the interior of the rings to obtain a
more
insulated construction and the sub-components of the section may be secured to
one
another using tongue and groove fastening mechanisms or other mechanical
means.
[0008] The invention includes the provision of an assembly machine which can
be used to produce the individual sections. The assembly machine may include a
plurality of adjustable arms that enable the length of the ribs (the height of
the
section) to be accommodated.
[0009] Each rib holder is rotatable with respect to a base portion about a
first
axis. Each rib holder includes an arm whose angle is adjustable with respect
to a
base portion so as to be rotatable about a second axis perpendicular to the
first axis.
Each rib holder further includes gripping members effective to hold the rib
therein,
in a manner whereby a plurality of sections of different members of ribs and
spacing
between ribs may be produced easily using the assembly machine.
[0010] The machine preferably has an odd number of arms, for example, 5, 7, 9,
etc., that varies, but typically accommodates seven ribs. Each arm has a base
that
moves on a specific calculated arc track on the table. This is true for all
arms except
the middle one that is fixed in place. The base of the arms move on these
tracks to
form an arc that is required in manufacturing the desired sections. All arms
rotate on
their bases typically from 0 to 90 degrees around an axis that is
perpendicular to the
track that the base moves on. This axis touches an inner lower point of the
section
produced, i.e., the arm rotates around the inner point of the bottom shoulder
plate.
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On each arm there are two movable angled sockets that are adjustable to
provide the
height of section (the length of the rib). Once the number of the desired
section is
produced, the machine is readjusted to produce the other sections. Again, this
is done
by moving the bases of the arms on the tracks on the table to produce the
desired arc,
then rotating the arm on the base to the desired angle and adjusting arm to
the
required length (in general the height of the sections is the same throughout
the dome
structure so there is no need to readjust). At this point the shoulder plates
and the
ribs are placed in place and nailed or stapled together.
[0011] The assembly machine can be used at a factory site and the individual
dome sections shipped to a construction site. Alternatively, the assembly
machine
can be utilized directly at a construction site. Several assembly machines may
be
utilized for one or several different dome constructions, with different
machines
designed to provide sections of different numbers of ribs, for example, a
first
machine for seven ribs, a second nine and a third for handling eleven ribs,
and so on.
[0012] The method for creating a dome structure comprises forming a plurality
of sections, each section including top plate structure, a bottom plate
structure, and a
plurality of ribs disposed therebetween, the ribs and plate structure having
an
arc-shaped cross-section; securing together respective top plate structures,
ribs and
bottom plate structures; placing at least two of the sections adjacent to one
another to
produce a first ring; placing at least two of the sections adjacent to one
another to
produce a second ring; and sections of the second ring becoming located on top
of
the first ring, the second ring having a cross-sectional area smaller than a
cross-
sectional area of the first ring. The second, third, fourth, etc., rings can
be optionally
fully assembled rings and then placed atop the previous ring or they can be
formed in
sections and then placed atop a lower ring or actually assembled on top of the
lower
ring. The entire ring or the entire dome can be produced in one piece.
[0013] Other features and advantages of the present invention will become
apparent from the following description of the invention which refers to the
accompanying drawings.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Fig. 1 is a perspective view of a dome in accordance with an embodiment
of the invention.
[0015] Fig. 2 is a front view of a section used to produce a dome in
accordance
with an embodiment of the invention.
[0016] Fig. 3 is a perspective view of a section used to produce a dome in
accordance with an embodiment of the invention.
[0017] Fig. 4 is a side cut-away view of a portion of a section used to
produce a
dome in accordance with an embodiment of the invention.
[0018] Fig. 5 is a top view of a shoulder plate used to produce a section in
accordance with an embodiment of the invention.
[0019] Fig. 6 is a side cut-away view of a first ring implanted into the
ground to
produce a dome in accordance with an embodiment of the invention.
[0020] Fig. 7 is two perspective views of an assembly machine for assembling a
dome in accordance with an embodiment of the invention.
[0021] Fig. 8 is four perspective views of an assembly machine for assembling
a
dome in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Referring to Fig. 1, there is shown a dome 50 which may be constructed
in accordance with an embodiment of the invention. Dome 50 is comprised of a
plurality of sections 52. Sections 52 are installed in the ground 54 and
disposed
adjacent to one another so as to form a ring 56 having a substantially
circular or
elliptical cross-section when viewed from above in the direction of arrow 51.
Rings
56 having successively smaller cross-sections are stacked on one another to
form
dome 50. Seven rings 56a, 56b, 56c, 56d, 56e, 56f, 56g are shown in the
figure. A
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space may be defined by each ring 56 so as to create an opening, such as
opening 58.
Opening 58 may be used for a window or door or the like.
[0023] Referring to Figs. 2, 3, 4 and 5, there are shown a plurality of views
of
section 52. Each section 52 is comprised of an odd number (5, 7, 9, etc.) of
ribs 60.
Ribs 60 extend vertically when used in a dome 50 and are comprised of studs -
such
as 2 inches by 4 inches wood studs. Each rib 60 may be, for example, 21 inches
by 3
inches by 2 inches. Each section 52 may include the same number, for example
seven, ribs. The center to center distance between ribs 60 at a bottom most
ring 56
may be 16 inches. This produces smaller distances at the top of the section
and the
top distances gets less and less the higher the ring or the section is located
on the
dome even though the spacing of the ribs through out the entire dome structure
at the
bottom of the sections or rings may be the same. This change in width helps
form
the dome shape. The shoulder plate dimensions may be 2" to 5" deep and 3/8"
thick.
For example, if the bottom length of a section is 9' and the top length of
this section
is 8', another section that is located above this section will have a top
length under 8'
when the bottom length is 9'. And so on. Ribs may change in size, but need
not.
[0024] An upper shoulder plate 62 and lower shoulder plate 64 are attached to
ribs 60 at top and bottom portions respectively. As shown most clearly in
Figs. 3
and 5, shoulder plates 62, 64 have an arc-shaped cross-section when viewed
from the
top or bottom. As shown most clearly in Fig. 4, each shoulder plate 62, 64,
has a U-
shaped cross-section when viewed from the side. The U-shape defines a groove
effective to receive a tongue 66 of a respective rib 60. Clearly other
fastening
structures aside from tongue and groove may be used to combine shoulder plates
62,
64 with respective ribs 60. The walls of the U-shape may be 3/8" in width and
made
of OSB (oriented strand board) sheets. Each rib 60 also generally has (but
need not
have) an arc-shape cross section, and the distal ends of the ribs preferably
have
angled cuts so that a top-most part of a rib is bent more inwardly toward a
center of
dome 50 than a bottom-most portion of the rib. As shown in Fig. 3, at a corner
of
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each section 52, a solid blocking stiffener 67 may be used to enhance
structural
integrity. Stiffener 67 may be 21/a" X 2" X 6".
[0025] A plurality of sections are disposed adjacent to one another and ribs
from
adjacent sections are fastened together using, for example, OSB sheathing and
fasteners, so as to form ring 56. Referring to Fig. 6, there is shown a side
cut-away
view of a first ring 56, Rl installed into the ground 54. As shown, l/2"
anchor bolts
may be used to anchor bottom shoulder plate 64 of the first section 52 of
first ring
56, R1 into ground 54. As shown in Fig. 1, a diameter of each ring 56 is
smaller than
the diameter of a ring vertically beneath it. Rings are connected to one
another
through the use of OSB strapping boards and fasteners. Once dome 50 is
assembled
using sections 52, OSB may be placed as a shell outside dome 50. Insulation
may
also be placed inside dome 50 as desired. A mesh or stucco finish or other
siding
materials may be placed outside the sheathing. Inside the dome, stucco or
drywall
may be used.
[0026] As can be discerned, dome 50 yields a modular construction. Sections 52
may be designed and constructed at a first location and shipped to a second
location
before being assembled. The assembly is simply performed by laying out a
series of
sections 52 and fastening them together to form rings.
[0027] Referring to Figs. 7 and 8, there are shown various views of an
assembly
machine 80 which may be used to produce a section 52 in accordance with an
embodiment of the invention. As shown, assembly machine 80 includes a
plurality
(e.g., 7) of rib holders 82 so that a distance between ribs in a section may
be
adjusted. Each rib holder 82 is rotatable with respect to a base portion 84
about a
first axis. Each rib holder 82 includes an arm 88 whose angle is adjustable
with
respect to base portion so as to be rotatable about a second axis
perpendicular to the
first axis. Each rib holder 82 further includes gripping members 86 effective
to hold
a rib 60 therein. In this way, a plurality of sections of differing numbers of
ribs 60
and spacing between ribs 60 may be produced using assembly machine 80.
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[0028] A dome construction system in accordance with the invention is unique
in
that it yields monolithic dome structures built with conventional building
construction components, in sections that can easily be assembled on site. The
unique structure provides a real dome atmosphere, contrary to the many-faceted
geodesic dome structures of the prior art. These wooden building systems that
take
the shape of domes may use small pieces of waste lumber (e.g., under 14"
long).
[0029] These structures have many advantages in addition to their strength and
flexibility. They are economical, energy efficient and environmentally
sensitive.
Each system may be one dome or a number of domes conjoined in any desired
fashion, and can be one or multiple story structures. Built in sections for
delivery to
construction sites, the system can be applied to produce domes of any shape
and size
up to 1,000 feet in diameter and can be used for residential and commercial
buildings, industrial and public structures, arenas and stadiums, and
emergency and
temporary shelters. For domes greater than 80' in diameter the system is
enhanced
by intersecting arches on the inside (similar to the waffle concrete slab in a
way).
This is done on site and by using standard lumber.
[0030] The dome's light and flexible body makes them virtually earthquake
proof and suitable for all regions regardless of snow load, wind and
earthquake
conditions. Paradoxically, the lighter the building, the better the results in
earthquake
and hurricane tests. A wooden dome in accordance with the invention is much
lighter than concrete domes. The structure's life span is expected to be more
than
twice that of conventional wood structures, thereby causing less ecological
damage
as the environmental impacts of these buildings are spread over a longer
period.
[0031] Construction time is greatly reduced - depending on size, the system
takes
as little as one to two days to assemble for medium size structures. In
addition, since
job site disturbance is minimal and environmental impacts of construction
waste
disposal are minimized, the system is suitable for environmentally sensitive
areas.
The domes are a value-added dream. They can use sawmill trim ends 14 inches
long
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and smaller, so the construction system is highly ecologically friendly. Waste
generated by seven dome buildings equals that of one conventional building.
[0032] The system is energy efficient (providing heating and lighting savings
of
30-50 %); flexible (with clear spans and no required interior support, space
can be
altered easily to accommodate future layout changes); and provides superior
design
aesthetics (with open spaces, better air circulation and improved light
distribution).
Domes are fine for homes and small buildings. Almost anything can be done
architecturally. Shapes could be elliptical, dome shaped or oval, and can even
be
constructed on top of rectangular or square foundations. Clear spans are
possible to
very large diameters and the structures can have any number of openings.
[0033] Although the present invention has been described in relation to
particular
embodiments thereof, many other variations and modifications and other uses
will
become apparent to those skilled in the art. It is preferred, therefore, that
the present
invention be limited not by the specific disclosure herein, but only by the
appended
claims.
