Note: Descriptions are shown in the official language in which they were submitted.
:~ 1S6078
SEG~ENTED SCREE~ CONSTRUCTION
BACKGROUND OF THE INVENTION
1. Field of the Invention
_
This invention, generally, relates to projected-image
vi~ual systems with screens and/or mirror3 having large radii
for exhibiting pro~ected images and, more particularly, to a
light-weight structure for a screen or mirror segment structure
to cooperate with a plurality of similar segments in the
construction of a larger project~d-image structure.
In the construc~ion of concave screens having large focal
lengths, it is well known that it is important to avoid defects
which can vary the focal point of the screen and become quite
visible when an image is proJected onto these screens. It is
particularly important in large focal length mirrors.
The screens or mirrors for exhibi~ing projec~ed images
that have been used in the past, with curvatures o~ a large
magnitude, have been difficult and quite expensive to produce.
This is because of the unusually heavy weight involved with
each segment not only due to the weight of each segment
but due also to the support structure required to maintain the
curvature faithfully.
Although such large pro~ection ~tructures have most
every conceivable curved configuration, even to the provision
of a complete sphere, varying the curvature of ~uch structures
has been neither convenient nor inexpensive. With present day
emphasis on cost o~ conjtructlon, a screen or mirror
constructed i~ accordance wlth the principles of the present
invention will reduce the cQst dramatically and will provide
a structure that is usePal, while provlding a ~ruc~ure whlc~
ad~ Oe ready sqrvicin~ ~o corr~ct de~ec~9 which develop
~o~ o ~ime.
; -
~r~
1 156~7~
Such large curved-surface structures for exhibiting
pro~ected ima8e~ are found to be uniquely adapted for use in
vlsual display systems for vehicle simulators and will be
described in this connection. An important improvement in
flight simulation and in similar display sy~tems was achieved
with the collimation of the displayPd image, i.e., by making
all image points appear to be at infinity. The problem of
providing collimation is complicated by any requirement for a
wide field of view, and optical systems are ~nown which will
provide collimated light for a wide field of view. However,
such systems have not been capable of providing inexpe~sively
collimated beams so wide that two or more trainees may view
the scenes simultaneously.
2. Description of the Prior Art
In the prior art, numerous training and 3imulator
apparatus have been constructed which embody a position from
which a trai~ee or pilot can manipulate control and observe a
~ response in a projected visual ima~e. For-example, the trainee
or pilot i9 positioned in a mockup of a boat, submarlne,
airplane, tank or other vehicle, and when he manipulates
controls, such as a wheel, stick or ~hrottle, the observed
visual scene responds in a manner which simulates corresponding
movements of the training vehicle.
The prior art pa~ents~w~c~ a~ a~nown to~have relevant
diqclosur2s are as follows~: 2,273,074, 3,6P07,584, 3,718,989
3,998,522 and 4,124,277.
However~ notwlthstanding the extensive efforts that
have been made i~ this field, there has not yet been shown a
segment structure to co-act with a plurality o~ segment
structures to form a lar8er structure with the degree of
accuracy in i~s curvature that is re~uired in the simulator
~ield in ordar ~o develop ~he required reali~ in the
r,~roJec~e~ ~cene. In additlon, Xrom ~he prlor su~eations ~o
divid~ a fnirror surPace into a l'series o~ ml~rors'~ or tha~ a
7 ~
"sc~een is composed of a number of small screen surfaces", there
is not one disclosure of how it can be done or ho~ to do it
lnexpenslvely.
SUM~RY OF THE INVENTION
A principal ob~ect of the i~vention is to provide a new
and improved structure for a qegment which admits of co-acting
with a plurallty of segment ~tructures to form a larger structure
for exhibiting pro~ected images with suffici.ent realism ~or use
in a proJected-image visual system of a sim~llator.
It i8 also an ob~ect oE the invention to provide such a
segment structure that is inexpensive ~o manufacture, yet main-
tains an unusually high degree of accuracy in the curvature
of the assembled larger structure.
In a presently preferred form of the invention, a
15 synthetic porous material, such as polyurethene foam, is
cured to a predetermined density and having two surfaces spaced
apart a predetermined distance, one ~urface having a curvature
that is defined as accurately as feasible. The i~vention
includes several different forms of means to attach and
20 3upport a predetermined number of segment structures so that
all of the accurately defined curved surfaces co-act together
to form a smooth, continuous surface.
.
DESCRIPTION OF THE DRAWINGS
The foregoing, other and further obJects, features and
25 advantage9 will appear re ~ully fro~ the detailed de3cription
of the presently preferred embodlments o~ the invention and
~rom the appended claims, both viewed in con~unction with ~he
a co~panying drawing~J where:
FIG. 1 i3 a per~pqctlve view, partly ln cro~s section,
3~ Oe a ~egmen~ed s~ructu~5 const~ucted in accordance wi~h the
p~incipl~s o~ the lnventlan.
PIG. 2 is a detailqd View o~ one end o~ FIG~ }.
FIG. 3 i~ a cross sectional view Oe a portlon o~ two
sa~ma~l~s showing how they are at~ached and supported ~oga~her.
1 1~807~
FIG. 4 is a plan view taken along the line 4-4 in FIG. 3.
FIG. 5 is a view taken along the line 5-5 in FIG. 4.
FIG. 6 is a diagrammatic illustration of ho~ two I-beams
at 90 to each other, are fitted together.
FIG. 7 is a top view of ~egments assemb}ed together in
accordance with the present in~ention.
FIG. 8 i9 a view of the end of FIG. 7.
FIG. 9 is a view taken along the line 9-9 in FIG. 7.
FIG. lO is a front view taken along the line 10-lO in
FIG. 7 shQwing slx matching ~egments assembled and attached
together to form a curved section.
FIG. 11 is an illustration to a stand to assemble,
align and test each section to ensure the smooth continuous
curvature of a segment Rtructure is malntained for an
15 assembled section.
FIG. 12 i5 a vertical, perspective view showing par~ of
a supporting structure for a plurality of segme~ts.
FIG. 13 is a view in perspective, partly in cross section,
of an entire sphere constructed of the segment structures, in
accortance with the principles of the present invention.
FIG. 14 is a diagrammatic illustration of a manner of
forming oue segment structure, in accordance with the
presently preferred form of the invention.
FIG. 15 is a diagra = tic illustration of a manner of
forming another segment structure in accordance with the
principles of ~he invention.
FIG. 16 is a diagrammatic illustrat~on of the formation
of still another segment structure i~ accordance with the
p~lnciple~ of the invention.
~0 FIG. 17 i~ a diagr~matic illu~ra~ion o~ ~he formation
a~ ye~ another segment ~tructure in accordallce with the
pre~ent in~en~ion.
11~6078
-- 5 --
PRESENTLY PREFERRED EMBODIMENTS
While the description hereinafter relates to a structure
whlch i~ unlquely adapted for wide-angle-dlsplay visual systems,
particula~ly for slmulator use, they may have other use3, as
one skilled in the art will readily appreciate.
In accordance with the present inveneion, a curved mirror-
or screen structure is divided into any desired number of,
preferably, equally sized segments. A reason for the present
de3ire to have ea~h segment of the same size is that 1~ is
contemplated that each segment is made from the same mald or
on the same master, as will be explained in more detail
presently, and the slze of each segment i8 determined by choice
as to the particular weight that can be handled and manipulated
conveniently.
Each segment structure, made in accordance with the
invention, is unusually ~trong and rigid in configuration, and
hav~ng a low weight, it provides an exceptional degree of
fidelity for the geometric curvature of the entire segment
surface. The features of construc~ion which contribute
substantially to its low weight are the e~treme thinness of
the segment skin and the light weight of the segment body.
Although each segment is made oE a tougher skin and,
therefore, is more resistant to abuse, yet if the surface of
a segment is da~aged in any way, the entire segment may be
removed and replaced easily, because of the particular
construction of the segment and bscause of the particular
means for holding and adjusting each of the segments relative
to ~ho~e ad~acent to lt.
Yet ano~her advan age Oè a cons~ruc~lon ln accordance
wi~h the inven~lon i9 ~ha~ ~he uni~ue s~ructure o~ each
~e~men~ e~fec~ively i~olate8 ~he optical surface o~ a screen
~r~ the mou~in~ 3ur~ace, 8ince each Be~ment s~ruc~ure i8
made ~ro~ the 3ame mold or pa~ern, i~ will ma~ch the ~d~acen~
~e~ment per~ec~ly, and ~hu~, lt will adapt readilq to
~ 1 ~60~8
assembly into a larger configuration. On the other hand, each
segment can be used as an entity if 90 desired.
In order to obtain maximum training value from vehlcle
~imulators, the trend is to provide such simulators with a
5 visual display ~ystem. Such a system can vary in complexity
and sophistication from a fixed scene that is pro~ected in the
pilot's field of vision to computer-controlled image ~lteration
3ystem~ with infinity image or CRT displays. ~ -
In the training of an aircraft pllot, costly flight train-
lng i9 avoided by providing a simulated cockpit of an aircraftwhereln there i~ a simulation of many aspects of the environ-
ment within the cockpit of an actual alrcraft. A portion of the
training includes the utilization of a ~imulated visual scene
from an aircraft.
The pilot US2S the visual scene outside his cockpit most
; often during a take-off or a landing. Therefore, most simulators
simNlate the vlsual scene near an airport. In one type of
simulator, a motion picture is made of the visual scene from an
actual aircraft during a landing or take~off. The motion
picture thereafter i9 projected through a complex optical
system to provide a simulated visual scene in realistic
perspective.
Due to the increased use of the visual system in
simulators today, there is a real need for a field-of-view a~
large a9 possible, yet of a new, lightweight structure for
use with a simulator. A structure in accordance with the
present invention, uniquely fulfills this need. The unit
wei~ht of each segment oE a ~i~ror and/or screen that is
conq~ruc~ed in accord~nce wi~h the prlnciple~ o~ ~he present
inv~nclQn ~pprQxi~ates two ~o fivq po~mds per ~quare ~oo~.
It i~ con~e~plated tha~ only by the manu~acture o~
qac~ ~egment from Chq sa~q mold~ or ~ro~ the same master, can
~he po~ential of uni~o~mi~y and preciqion at a reasQn3ble
cost 4e realized. Any proce~ o~ manu~ac~ure, ~hat re~ts
1 15~0~8
-- 7 --
mainly on skilled labor to produce uniformity of geometry and
finish, implies the risk of discontinuity in several aspects
aside from probably prohlbieive costs ln producing a great
number of segments. Moreover, the probability of mismatches
when ~oini~g such variou~ly made segmen~s wGuld be very high
in spite of the close dimensional tolerances.
The pre3ent inventlon, in its broadest aspect, contemplates
the manufacture o~ segments of a screen of larger dimensions by
formlng from the same mold individual segments of relatively
large-area and substantially thin (when compared with its
larger area), and o~ substantial strength, such as by the
relatively new Reaction Injection Molding (RIM) technique.
Such polyurethane structural foam has a high strength-to-weight
ratio, when used with RIM production process, and produces a
segment structure with an integral, solid skin and a micro-
cellular core.
The polyurethane structural foam is the result of a
balanced chemical reaction between a polyol and an isocyanate.
In the reaction injection molding process, these liquid
components are metered into a mixing chamber from which they
are in~ected at atmospheric pressure into a closed mold. The
mold i9 partially filled, depending upon the density of
the finished product desired, and the mixture then expands
to fill the entire mold space. The pressure developed during
the foaming is relatively low, approximately 40 pounds per
square inch.
Since polyurethane structural foam duplicates the mold
surfaca, it i3 usual to have the mold surface as highly
polished and s~ooth a~ posslble, It i~ already Light in color?
and therePore, P~r most use~, ~u~the~ ~eatmen~ ~or colq~ 1
unn~ceq8ary. ~or use~ whe~e loads mu~ be secured ~o ~he
polyur~t~an~ s~ruc~u~al P~am seg~ent, local ~einPorcemen~
wl~h me~al i~ser~ may be necessary,
I 1 5~;078
- 8 -
These inserts can be foamed in place. For foamed-in-
place lnser~s, the insert i9 Eixed in place so that it does not
move during the foaming phase. To improv~ adhesion between the
segment and a metal insert, the metal surface ls roughened
and degreased.
For a simple, one-time connection, wood or self-eapping
screws can be inserted directly into the polyurethane structural
foam after it is culed. The screw pull strength is dependant
upon such factors as screw size and pilot hole dLameter. Screws
should only be used in those segments with an overall density
highPr than 25 pounds per cubic foot.
The mold temperature must be controlled closely and
precisely to obtaln the results desired, i.e., the particular
de8ree of density within the foa~ed material when it is cured.
This density of the foamed material is the primary factor i~
determining its weight as well as its strength, and therefore,
it i9 desired to have a low density in the center of the
material, which density becomes increasingly higher (or more
dense) as one proceeds toward the surface of the material.
This temperature is controlled by maintaining its variations
between two de8rees C., making it essential to use only good
heat conducting molding materials. Tempered wa~er is used as
- the best medium for controlling this mold temperature.
It i8 important to note that the lnformation concerning
the polyurethane structure foam is ~urnished for the benefit
o~ the artisan attempting to follow the teachings of tke
present invention, and, in and o~ itself, forms no part o~ the
present invention, It is ~he structuxe Oe the par~icula~
~e8men~ ~ha~ i9 the inven~ive ~eature here. Accordingly, the
30 lnven~lon ~hould in na way be limited to ~he par~icular pla~ic
mate~ial usqd to ~o~m ~hq basis o~ ~he segment, ln tha~
o~her, dl~e~en~ and varlous materials may bq used, as bq~er
within the p~view a~ an ar~i~an skilled ln that art.
1 1 58~78
For example, in place of polyurethane foamed structures,
reinforcing with carbon rather than glass fibers may be More
effective for some u3es, even though carbon fibers are much more
costly. Another particular material is a percentage glass-rein-
S forced polycarbonate, or a polyphenylene oxide structural foa~may be used.
Of course, many other materials may be known to an
artisan skilled in this art which might be appropriate ~or use
in a particulsr segment structure, and seill other and
diEferent materlals mlght be available in the future.
Accordingly, it is understood that the present invention is in no
way limited to the particular material described in this
presently preferred embodiment.
One alternative arrangement of materials with which a
construction in accordance with the principles of the inv~ntion
is uniquely adapted to be effective utilizes a segment ~ormed
of a suitable synthetic porous material with an appropriate
~etal, such as aluminum, nickel and the like, electro-formed on
the optical surface in a very thin layer. There are companies
today quite skilled in the electro-forming process.
Referring now to FIG. 1 of the drawings, the reference
numeral 10 identi~ies one segment of a larger 3tructure, and
the reference numeral 11 identifies a second segment of the
same structure, the segment 11 being identical with the
segment 10, having been formed on the same mold or paetern.
The optical surfaces 12 and 13 of the segments 10 and 11,
respectively, are continuous and smooth, partlcularly at the
line 14 where they ~oin, and have a large radlus of curvature.
~hQse 9urPaces 12 and 13 are appropriately fo~med to rePlect
3~ an ima~e which i9 pro~ec~qd ~h~reon a~ ln a normal si~ula~ian
apparatu~.
~ IG. 2 Oe ~he drawings 1~ an enlar~ement o~ onq carner
Oe thq ~qgmen~ 10 in order ~o reveal it~ cons~ruc~ion wlth ~ore
pflrticularlty, ~or exa~ple, i~ may b~ see~ in FIG~ 2 ~ha~ the
3~ sur~acq l~ is actually ~or~ed by a sepa~a~e skln lS which is
1 15~78
-- 10 --
ldentical to, in this particular embodiment of the invention
st N cture, a second skin 16 spaced apart therefrom and sealed
thereto by a plas~ic foam filler 17. The two skins 15 and 16
are relatively thin~ preferably a typical example ~ould be
.031 inches max., as compared with a thickness of 2 inches
between the inner surfaces of the skins 15 and 16. The
plastlc foam filler 17, which i~ fo~med in place, bonds and,
therefore, adheres readlly to the inner 3urfaces of these
tw~ skins 15 and 16.
The two segments 10 and 11, as stated previously, are
~hown in FIG. 1 positioned approxima~ely correc~ly relative
to each other to form a smooth, continuous surface, without
there bein8 shown any means for holding the~ in this position.
In FIG. 3 of the drawings, there is shown a way, presently
preferred, of attaching these two se~ments together to support
them in this position.
Referring now to FIG. 3, a type of insert 21 shown
imbedded in the foam 22 adjacent the upper edge of the upper-
most segment is shown with a flange 23 which may be any
de9ired configuration, such as circular, square, octagonal,
etc. Moreover, the flan8e 23 may be perfora~ed with one or
more rows of apertures 24 if desired, or it may be solid, it
being a matter of the strength desired to be held by the
insert 21.
The insert 21 also has a body 25 ~hich may be any
desired configuration, and the body 25 may have a series of
ralqed surPaces 26, like deep thread~, in order to give it
mor~ re9i~tance t4 eXtrac~ion ~rom within the ~oam 22. ~he
in~ert 21 ha9 a ~en~rally locatqd aper~ure 27 in whlch a
bolt 2~ i~ threaded a~ainst a wa~her 29. Uisposed be~ween
the head 30 o~ th~ bol~ 28 and ~he wa9hqr 29 is a lock wash
31 in ordqr ~o ~ur~her secure the bel~ 23 ~lrmly in place.
The body 32 of the bolt 23 ~i~8 within an enlarged clearanc~
openin~ 33 which pqrmi~s ad~ustmen~ oP po~ition Eor the
s~ments, aq wlll be explained in mere detail presently.
- 1 15~078
The lowermost ~egment ~tructure, as viewed in FIG. 3,
ha~ a ~olid skin 18 on the back or reverse ~ide thereof for
the rigid, lightweigh~ porous core of synthetic foam 20, and
it has, al~o, a skin 19 on the opposite surface which may be
of a different material from that of the solid skin 18, but
the ski~ 19 mu~t be solid and tough, as must be the skin 18.
In this view of the inventive structure, the ~kin 19 is
highly polished, more reflective, mlrror-like finish, such
as aluminum with a protective coating thereon. Alternatively,
it can be a very thin glass plate, or it can be plaQtic, in
order to achieve a hlghly reflective quality.
An lnsert 34 tha~ is shown near the edge of the lowermost
segment in FIG. 3 ha~ a body 35 wlth a plurality of dull or
rounded ~errations 36 along its length to increase it3
r2sistance to extraction from the foam 20. An aperture 37,
located centrally ~ithin the insert 34, opens externally through
the skin 18 to receive a threaded end 38 of a bolt 39. The
bolt 39 has a head 40 which squeezes and firmly grips a lock
washer 41 against a plain washer 42.
The bolt 39 has a main body 43 which extends from the
head 40 to the threaded end 38 and which fits within an
enlarged clearance opening 44, the purpose of which wlll be
explained in more detail presently. Both of the clearance
openings 33 and 44 are located in a flange 45 of the I-beam
46, with a matchlng flange 47 ~paced a predetermined distance
from the fla~ge 45.
A pluraLity of U-~haped spacer washers, indlcated by the
reference numeral~ 48 and 49, serve to space the flange 45
~rom ~he ~klns 18 and 18', which may vary from p~int to point
3~ becau~ th& skins 18 ~nd 18' are curved lnto a predetcr~ined
~hapq, as viewed be~ ln FIC. 1 a~ ~he drawing~. Accordi~ly,
~inc~ ~he I~bea~ 46 19 contemplated as being only ~ htly
cuXv~d and not nqceqsarily curved to match ~he configurations
oP the 9e~qn~? ~he elangq 45 will vary in dis~ance grom
3S ~he ~kin ~' at varioua polnt~ aero~s i~s length.
l 156078
- 12 -
It is impo~tant to note a space 50 located between the
flange 23 of the insert 21 and the inside surface of the skin
19'. One reason for thi~ space is to permit the foam ~2 to
enter and seal the insert adhesivaly to both the inside surface
of the skin 19' and, thereby, fixedly positlon the insert 21.
However, an even more lmportant resson for this space 50 is to
prevent any distortion in the surface of the thln skin 19', which
would occur if it touched on the inside surEace, because the
skin 19' is so thin that any ob~ect touching on the inside
gurface would be vlsible through it and would cause optical
aberrations on the face vlewed.
Another i~portant feature seen in this FIG. 3 is the
space 51 between the adjacent edges of the skins 19 and 19',
which is typical of the gap between adjacent 3kins all the way
around each segment. The space 51 is small, in the arder of
.030 inch ~ .003 inches, and is for the purpose of preventing
any chipping as would occur if the skins 19 and 19' are glass
and they touched.
To fixedly position adjacent segments with the spacing,
as indicated by the space 51, a suitable resilient separator,
preferably a silicone plastic, is injected into a space 52
and molded in place upon the completion of the assembly, as
will be deqcribed in more detail presently. This will
fixedly secure the two segments adjacent each other, preventing
their touching with a solid impact sufficient to chip the
edge o~ a surface.
As better seen in FIGs. 4 and 5, a dowel pin 53 fits
snugly into a hole 54 drilled all the way through the flange
4S Oe each I-beam, ~he spa~ers 48 and into the body 25 a~ t~le
30 insert 21. The manne~ ~ eixlng these dowel pinq, such as t:he
pin 53, pre~erably tw~ per ~e~ment, will be described in ~o~e
de~ail presen~ly. However, Ju8t b~ie-Ely, once the seg~en~8
h~ve been ad~u~tqd care~nlly t4 Xix the space 51 between them,
a~ in ~cco~d~nce wi~h ~he dasired dimen~ion given above, ~he
b~lt 28 and ~he bolt 39 Are tlghtened. Then, while the
1156078
- 13 -
segments are being thus held in place, a hole is drilled
such as the hole 54, in FIG. 5, and the dowel pin 53 i9
driven into place, thus fixedly securing the dimension 51.
A similar pin 55 i9 shown for the insert 34, in FIG. 4.
The I-beam 46 extends continuously past the two sides
56 and 57, respectively, is best shown in FIG. 4 of the
~rawing~. The fillet weld 58 is shown on each side of the
side 56 and also on each side of the side 57 to ~oin these
two to the I-beam 46. In FIG. 5, the fillet weld 59 is shown
to ~oin the side 56 also to the horizontal flange 45 of the
continuou~ I-beam 46.
In FIG. 6 of the drawings, there i9 shown how two I-b~ams
are Joined together perpendicularly. The bottom flange 60 of
the l-beam 62 is cut off along a line 63, and in like manner,
the top flange 64 is sut off along a line 65, le~ving a
pro~ecting extension 66, which is that portion of the body 62
that extends past a line drawn between the line 63 and 65.
As best seen in FIG. 6 of the drawings, an extension 66 is
formed by that part of the body 62 which remains after the
upper and lower flanges, 64 and 60, respectively, are cut off
back to the respective lines 65 and 63. The edge 67 will touch
against the surface 6~ of the I-beam 46 ~ust when the line 63
touches the end 69 and the line 65 touches the end 70.
Thereaftcr, firm ~oints may be made by suitable welding, or
any other suitable attaching means.
Referring now to FIGS. 7, 8 and 9 of the drawings, it is
shown how a plurality of segments are Joined together to form
a "~ection" havin~ a desired number of segwents. FIG. 7 shows
more par~lctllarly a top viqw of a ~ection having ~hre~ ~eg~en~
3q 71l 7~ and 739 r~pec~ively. However, hlso vl~ible in FIG. 7,
i~ a por~ion o~ ~hrqc additional segment3 74, 7S and 76? ~oined
al~o to the segmqn~s 71, 72 and 73 along a line indicat~d by
~hQ re~erence nume~al 51, identified more par~icularly in
F~G, 3 of ~he drawln~ hi~ same re~er~nce n~m~ral Sl 1~
3S n~ed he~e ~o indicate that the ~pacln~, in ~he o~der of .030
~ .
I
1 1 56078
inches, ls common between all segments, generally. In
addition, the same refarence numeral 51 is used to indicate the
spacing between ad~acent segments 71 and 72; and be~ween ad~acent
segments 7Z and 73.
While I-beams are utilized in these respective Figures
for the purposes of this illus~ration, therle are available
alternative forms of construceion to affix iad~acent segments
to each other rigidly and ~o provide the neces~ary overall
support. Such an alternative is shown in FIG. 8 of the
drawings as being an alternative to that end referred to and
lden~ified in FIG. 7.
In ~IG. 8, two channels 77 and 78 are bolted together as
illustrated by the straight lines 79 and 80, respectively.
With the channels 77 and 78 firmly affixed to each ~ther,
the resemblance to an I-beam is present.
~ owever, having the so-called I-beam in this form of
structure, i.e., the two channels 77 and 78, admits of
another means to space the tw~o segments with respect to each
other in order to accurately obtain the spacing 51. By way
of example, the channels 77 and 78 may be affixed at the
borders of the respective segment structure~, and then, when
the rwo segments are positioned next to each other and when
the ~pacing 51 is established, a washer or other suitable
spacer may be placed within the gap 81, before the channels
77 and 78 are bolted together ac 79 or 80.
FIG. 9 is a side view of this section, but taken aIong
the line 9-9 ln ~IG. 7. It illustrates the effectiveness
o~ the I-beam supe~s~uc~u~e ~o~ 9upp4rting the lndividual
seg~ent s~ruc~ures 73 and 76 in rela~ion to aach other ln
4rder tQ ~ ly a~ix tha 9pacq Sl. In ~his side view o ~he
sec~i4~, ~he spac~ 82 i9 clearly vislblq between the
lowq~m4st flang~ 83 o~ the bo~to~-to-top I-bea~ 84.
I~ is con~emp1ated, ~l~hough no~ e~sen~ial, ~h~t ~he
ve~tical I-bea~ 84 is the contlnuou~ one, whereas the ~ide-~4-
7 8
- 15 -
side I-beams are arranged to abutt in a manner as shown in
FIG. 6. In this FIG. 9, the lowermost I-beam i~ identlfled
by the reference numeral 85, whereas the uppermo~t I-beam is
identiied by the reference numeral 86 and the i~termediate
I-beam i~ 87. Al~o as ~hown in FIG. 9 are ~our spaces
identifled from top to bottom as 88, 89, 90 and 91.
Whereas the view in FIG. 9 includes approximately 40
degrees, the top view shown in FIG. 7 includes approximately
60 degrees.
FIG. 10 is a full frontal view o~ the assembled section
~s shown in FIG. 7 or the drawings, taken along a line
10-10 in FIG. 7. In this view, each segment is identified
by reference numbers 71, 7Z, 73, 74, 75 and 76. It is
contemplated that the vertically positioned I-beams,
identified by reference numerals 92, 93, 94 and 95, in
~IG. 10, are continuous, as viewed in this Figure, as
contrasted with the horizontally arranged I-beams 96, 97
and 98, from top to bottom, which are intermediate of
the vertical I-beamR and are attached together as illus~rated
in FIG. 6.
Also shown in FIG. 10, for the segment 75, there are
indicated four crossline~ and identified by the reference
numeral 99 to illu~trate that in each of these positions, a
cast-in-place in3ert i~ positioned during formation of the
segment structure and used to facilitate carrying by
tempor~rily attachin~ a suitable handle (not shown). It is
contemplated that each segment structure, man d actured in
accordance wlth the invention, that iq o~ su~ficient ~ize to
make handling otherwise awkward, such cast-in-place inqerts
may be. 90 included.
Sinee each of the segment structures are c~nstructed and
eormqd ~o~ the samq identical mold, ~hey are id~n~ical ln
~lze and in arc~e qh~p~. A p~deter~ined ~umbe~ o~ such
~e~m~nCq a~e a~qmbled together tQ Eorm a ~hape s~mewhak
3S la~gq~ (~uch as tha~ ~ho~n ln FIG. 10) and is called a
1 1 560~8
- 16 ~
"section", for the purposes oE this description. A "section"
i9 assembled of a deslred number oE the "segments", and any
convenient method may be used in such asgembly.
As shown in FIG. ll of the drawings, a convenient way of
as~embling these segments is on a large table lO0, having an
upper surface lOl in or~er to support the s1:ructure being
a3sembled. By a series of vertically positioned members 102 wi~h
suitable braces 103, the table lO0 ls supported in an elevated -
position relative to a floor surface 104.
In ~his illustration, there are three segment structures
vlsible on the table lO0, they being segments 105, 106 and
107, in order to form a section 108. By a suitable gauge
~not shown), the space Sl is set by adjusting the position of
ad~acent segments. Ihen, a suitable resilient separator
lS (such as a fluid silicone mixture) i8 injected and molded in
place, as described in connect~on with FIG. 3. Since each of
these segments are supported vertically on the table lO0,
once the silicone mixture is set, the gauge may be remo~ed
because there are no forces acting upon each segment structure
to alter the spacing.
Various I-beams, or other segment support structure, are
arranged within the space identified by the reference numeral
lO9 and supported appropriately on the upper surface lOl of
the table lO0. Then, a plurality of individual segments
(three bein8 visible in this view, 105, 106 and 107) are
attached to the I-beams, a~ explained in connection with
FIG. 3, supra.
A~ is well known, an important factor in the cost of any
~aterial ordered from a vendor is dependent directly upon the
de&ree of tolerance speci~ied when ordarin~ the material.
There~ore, whiIe ~he I-bqa~q are ord~r~d ~o a desired
cu~vatu~e, the ~alera-ncq m~y 4e in ~ha order o~ inch~
and the d~viation9 ~ro~ the deqired curvature a~ co~pen~ated
Eor by qpaeer~, indicated by the re~erence numerals 4~ and
4~ in ~IC. 3 and ~he sp~cerq 48 an~ 49 bain~ ITY~haped perm:l~s
1 1561)'~8
- 17 -
the~ to be slipped into place about the resp2ctive bolt
without removing the bolt.
By any suitable structure, a hook indicated by the reference
numeral 110 is located and fixedly positioned A distance from
~he surface of the section 108 equal to tbe radius of its
curvature. A suitable radius gauge is formed by having a
non-extensible member 111 to accurately position a plumb 112,
having a plastic or other soft tip, an accurate distance above
the surface of curvature for the section 108. Then, by moving
the plumb 112 about the surface in any desired direction, any
deviation ln the curvature of the section 108 will become
apparent immediately.
A atructure ldentified generally by the numeral 113 selves
to provide the non extensible member 11 with the desired length.
It is important that the hook 11~ be fixed positively, as well
as accurately~ and to accomplish this, the structure 113 has
surfaces 114 and 115 which are flared apart upwardly until
they reach a surface 116, such as a ceil$ng or, as seen in
this view, as formed by a horizontally arranged beam 117. The
beam 117 is braced by diagonally arranged braces 118 and 119
attached between the beam 117 and the downwardly flared apart
support legs 120 and 121, positioned on pedestals 122 and 123,
respectively.
In FIG. 12 of thte drawings, there i9 shown, by way of
illustration onlyl one structure ~or superstructure) 124 for
supporting a plurality of sections embodying more than one
Yegment each. The particular number of segments that ate
~oined at ehe factory prior to shipping ls dictated by such
considerations as welght, convenience and ease of handling the
section. If the surface of the segments is that of highly
rePl~ctlve macerial, such as polished metal or even a glass
mi~r~ ~urface, then the weighc mi~h~ be expected to be
sub~tantiaLly more than iP only a scrqen surface is lnvol~ed,
1156078
- 18 -
For the heavler weighlng segments, perhaps only four
segments might be Joined to form a section, such as segments
125, 126, 12g and 130, or alternatively, 125, 126, 127 and
128. The segments 131 and 132 ~ight be ~oined together at the
factory as a cwo-segment section, or alternatively, these two
segments 131 and 132 mi8ht be combined at the factory with
segment~ 129 and 130 or with segments 127 and 128, it largely
being a matter of choice, dictated by convenience.
The particular supporting supPrstructure, illustrated
by way of example only in FIG. 12, is depicted in sufficient
detail that a description thereoE is not believed to be
necessary, because the particular superstructure is not an
aspect of the present inventlon, but rather, goes to illustrate
another use for the invention.
In FIG. 13 of the drawings, the particular invention is
shown in an environment in which it is believed to be a
particular benefit in the simulator art. Here, the invention
is used to form a complete sphere with a screen-type of
surface, indicated by the reference numeral 133. A plurality
of identical segment structures 134 are ~oined in a manner as
has been deYcribed already in order to form a sphere,
indicated generally by the reference numeral 135.
The particular suparstructure to support the individual
sections, each composed of a plurality of segments 134, i9
not shown because it can be removed once such a spher~ 135 is
completed. Of course, if the simulator is not a fixed-base
type, but rather is a mation-base type, the supportive
super~tructure may be retained in place. With the support
structure removed, however, each segment structure supports
the adJacent segments, making a superstructure unneces~ary.
A small opening 136 i~ left in this structure to provide
a~ceq~ ~o a 3i~ula~4r ~pp~ratus 137 located wl~hln thi~ sphere
13S in ~uch a mann~r as ~he qyepoln~ 13~ will be at ~he
geo~ecrlc cen~er o~ the ~pherq ~or ~aximum r~l1sm of an 1mage
3S p~o~ected upon ~hq scrqen 133. ~he openlng a~ the very ~op
1 1 560 7 8
-- 19 --
of the sphere 135 is small and i9 filled by a single 3egment
made to fit that opening.
To illustrate a pre~ently preferred method of making each
segment structure with either 8 screen or a mirror surface, in
accordance with the present invention, reference is mate to
FIG. 14 of the drawings. In this view, a fixed mold is
indicated by the reference numeral 139 and has a plurality of
openings 140 for the circula~ion of either heating or
cooling medium, such as tempered water, to contol the
temperatu e of the upper surface 141 precisely. The surface
141 is the critical part of this mold 139, because it is of the
same radlus as the flnished screen or mirror. By using the
same surface to form each 3egment, clearly the curvature of
the final product will be the desired curvature.
The total area of a desired display surface is divided
into an equal number of segments of equal dimensions,
preferably rectangular, but, however, they m~y be s~uare,
which is a speclal form of a rectangle. Then, knowing the
rectangular dimensions of each segment, an angle 142 is formed
of a suitable material and is joined at its ends to form a
generally rectangular border to match the desired shape of
each segment structure.
Then, the ~oined form of angle 142 is laid upon the mold
surface 141 to define the border, as described, and in FIG. 14,
it 19 contemplated that ehe border definlng angle 142 will
become part of the segment structure. However, this need not
be the case in every instance. For example, the means to
deflne a suitable border can be attached to either the mold
139 or, preerably, to an upper platen 143. It can be at an
appropriate angle ~o form a V-shaped trough with the border
o~ an ad~acen~ aegmen~ atruc~ure, as ~hown in FIG. 3 by ~he
re~qrence nume~al 52,
11~607~
- 20 -
The upper platen ~43, being movable vertically, is
ad~usted ~o ~ust touch the rectangular configuration for~ed
by the an$1e 142. This defines a cavity 144 between the lower
surface 141 and a surface 145 on the movabl~ upper platen 143.
S The temperature of the surface 145 is controlled, like the
temperature of the 3urface 141, by a plurality of holes 146
in order to circulate either a heating or a cooliI~g medium
from a sultable source 141.
With the space 144 accurately defined as described above,
predetermined quantitles of a polyol and an isocyanate
are metered into the space 144, which can serve now as a mi~ing
ch~mber, partially filling the spacq 144, depending upon the
density of the finished product desired, the mixture reacts
and expands to fill the entire space. During the curing
process, the temperature of the mixture is controlled closely
and precisely to obtain the desired results. The foam
material i3 in~ected from a suitable supply 148 through any
convenient access opening 149 into the space 144.
A segment constructed in the manner just described
lmmediately above is the presently preferred form, i.e., where
the foam itself forms the surface to be used as a screen.
The polyurethane structural foam segment formed in this manner
~ay have a density sufficiently dense along its concave surface
formed against the mold surface 141 to permit it to be highly
2S poli3hed and, preferably, coated with a highly reflective
material by any of the present-day known processes, such a~
electro-forming an ultra-thin but highly reflective coating
of aluminum, nickel or the llke.
In addition, the surface of the segment qtructure that
is formed a8ainst the surface 145 also is the denser foam
su~f~ce and is e~tirely sultable, in many instanceq, to attach
lt ln pl~ce with o~dl~ry w~od screwa~ ~or examplq,
quppor~ ~or ~he se~men~ qt~uc~ure may be provlded by
inse~ing directly i~t~ thi~ dqnser Poam ~art o~ the ~e8m~nt
s~ructure a ~ui~able self-tappin~ ~crew.
1 15B078
- 21
The above description suggests a modificaeion which i~
illustrated diagrammatically in FIG. 15 of the drawings. In
thl9 view, the sa~e mold 139 may b~ used wLth its upper
conYex surface 141 and a plurality o~ hole3 or tubular
opening~ 140 to receive the heating ant coolin~ medium.
A positioning s~op 150 is located ad~acent one edge of
the mold 139 to position accurately each part to be formed
on the surface 141. In thi~ view, a lower skin 151 is laid
directly on the mold surface 141 with one edge against the
po~itionlng stop 150, and then, an identical upper skin 152
~ith suitable end angles 153 and 154 attached is posltioned
over the skin 151 and again~t the positioning stop 150,
forming a generally rectangular space 155.
The stop 150 has a surface 156 against which the angle 154
is positioned to give the angle 154 the correct position
relative to the lower skin 151 for the finished segment. By
way of illustration, the angle 154 as well as the angle 153
and the other ends (not ~isible) may be positioned wi~h a
desired tilt to form a somewhat V-shaped opening between
adjacent segments for filling with the desired resilient
material, as the space 52 qhown and described in connection
with FIG. 3 of the drawings.
In FIG. 15, two inserts 157 and 158 with respective flanges
159 and 160 are shown held in position by short screws 161 and
162 against the upper skin 152 in order to define a space 163
and 164 between each respective flange 159 and 160 of the
inserts 157 and 158 and the lower skin 151. It has been found
tbat the space~ 163 and 164 are required in order to prevent a
disto~tion being vi~ible th~ough ~he lower skin 151. Therefo~e~
~he ~paces 163 and 164 are iu~t su~icient for a layer o~ ~he
~oamed ma~erial ~o flow between the ~langes lS9 ~nd 160 and the
lower skin 151, ~hereby makin8 the ~lan~es 159 and 16~,
re~pectively, invlsible a~ vlewed through the lower skln 151.
7 8
A suitable 3ynthet~c porous ~aterial is injected, as
illustrated diagrammatically by the reference numeral 165, into
the spsce 155 at about the upper~ost point ln order to prevent
air being trapped as the synthetic porous material expands
during the curing process. The material, for example,
polyurethane ~tructural foam, is cured in place in the
chamber 155 and is sufficlently strong to miake the entire
segment structure unusually strong and rigid.
Therefore, after the polyurethane i9 cured, the temporary
screws 161 and 162, as well as any otherY that might be holding
foamed-in-place inserts in their proper posi~ion, are removed
to permit either ~he temporary attachment of a handle fo~
manipulating the segment structure or for the attachment of
an I-beam, as illustrated in FIG. 3 of the drawings. By
attaching to the upper skin 152 the two inserts 157 and 158
as well as the angles 153 and 154, all of this activity i9
benchwork, ~hare it can be done much faster and with a much
higher degree of accuracy than at the manufacturing site.
As clearly visible in FIG. 15, each of the two angles
153 and 154 is not illustrated as being fixedly attached to
the lower skin 151. In practice, the lower skin 151 is
placed upon the mold surface 141, and since the lower skin 151
is relati~ely thin and flexible, it will immediately assume the
configuration of the surface 141.
Thereafter, the assembled unit of the upper skin 152 with
all of the inserts (such as the inserts 157 and 158) and the
surrounding angles ~such as the angles 153 and 154) is placed
over tha lower skln 151 and i9 positioned against the qtop
surface 156. After the polyurethane structural foam i5 cured
3~ withl~ th~ ~pac~ lSS, the synthetic porqus ma~erial eorm~ a
ri~ld attach~ent adhasively ~ixin~ the lower skin 151 to the
upper ~kln 152, as well a~ wi~hin the spaces 163 and 164 and
within thq channels o~ the a~gles 1S3 and 154, making
~ur~her ~ach~n~ unnecqs~ary in order to lift the
lqwer ~kin lSl wi~ the upper skin 152~
1 1 ~6078
- 23 -
Referring now to FIG. 16 of the drawings wherein lt is
shown a further embodlment of a seg~ent constructed in
accordance with the principles of the inventlon. Here a very
thin mirror skin 166 is laid over the surface 141 of ~he mold
139 and is positioned againgt the stop lS0.
An upper skin 167, then, with all of its attachments,
such as the angle~ 168 and 169 and the inserts 170 and 171,
is positioned against the stop surface 156 over the lower skin
166, as illustrated in FIC. 16 of the drawings. As explained
above, the angles 168 and 169 are not attached to the mirror
skin 166 becau~e they would be visible through the skin.
Each angle member 168 and 169 is sharpened at one end
to a fine line ed8e as illustrated by the reference nu~eral
172 in FIG. 16 in order to minimlze contact area with the
15 - surface of the skin 166. Because of this characteristic of a
surface against the lower mirror skin 166, ~he two inserts 170
and 171 are maintained out of contact with the mirror skin
166, as illustrated by the spaces 173 and 174 and as explained
in detail above.
The inserts 170 and 171 are fixedly attached to the upper
skin 167 by mean~ of a Ionger threaded member with a nut 175
and 176, respectively, intermediate of this threaded ~ember,
to leave extending from the upper skin 167 a substantially
longer threaded end 177 and 178, respectively.
Z5 By this means, the foa~ed-in-place inserts 170 and 171 are
fixedly attached to the upper skin 167 and need not be touched
further because the extended threaded ends 177 and 178 are used
to insert through a larger hole in the flange of a sultable
I-bea~ for attachin~ ad~acent segment edges. Of course, by
3~ a~aching ~he se~ment s~ructures in ~hi~ manner ~o an ~-beal~,
~h~ ~hreaded qxt~nded end~ 177 and 178 need only have a
3uitable spacer washer inserted and then a nut threaded over
each end ~o malce ~hem opera~lve. A9 illustra~ed 4y the
rq~erence numeral 179, a suitable syn~he~ic porous material
i~ inJected within the cavity 180.
1 1 5~078
- 24 -
Yet ano~her embodiment of a ~egment, constructed ln
accordance with the princlples of the present invention, is
illustrated by the diagrammatic view in FIG. 17. A thin glass
sheet 166 is laid on the curved surface 141 of a mold 139 with
thz border angles 142 carefully positioned thereover so that
the edges will match the ed8e~ of the glass ~Ikin 166, as
illustrated by the reference numeral 181, fo~ing a line
contact with the skin 166.
Then an upper pla~en 182, which is movable vertically, is
lowered to touch the edges of the borde~ angles 142 thereby
defining a space 183. From a suitable sGurce 184, a
polyrethane structural foam is inJected into the space 183S so
that as lt is cured, it will expand to touch the upper
surface 185.
From a suitable source 186 of heating and cooling, a
suitable fluid is circulated through the openings 187 in order
to control the curing of the polyurethane that has been in-
jected into the space 183. Since no foamed-in-place inserts
are illustrated in this view, the foamed polyurethane may be
cured to a degree that makes it more dense than usual by
controlling its temperature, and the segment structure is
attached to a 3uitable support and to each other by wood
screws, as described prevlously.
In view of the above detailed descrlption of the presently
preferred form of the invention and in view of the detailed
description of various modifications thereto, other and still
further modificatons, variation~, advantages and uses will
occur to one skilled in this art. Accordingly, the description
and ~odifications pre~en~ly presented hereinabove are ~o he
considered ~9 illus~ra~iYq only, ~h~ ~rue ~pirl~ and scope o~
the inv~io~ beiny tha~ deEined by ~he claims appended hereto.
