Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention relates to grid-type suspended
ceilings such as are currently in widespread use in modern
building structures, for example, large public buildings such
as shopping centers, theaters, garages, and the like, and
relates more specifically to apparatus which facilitates
installation of junction boxes which are capable of reliably
hanging lighting fixtures and appliances which are of con-
siderable weight.
Suspended ceilings comprised of insertable and
removable ceiling panels (blocks or tiles) are structurally
incapable of supporting heavy fixtures, such as lighting
fixtures, and the like. Therefore, only a limited number of
available fixtures are of sufficiently low weight to allow
usage with such ceilings, a flush-mounted or recessed fixture
of light weight usually being employed in place of a single
ceiling panel. Therefore, the art has previously provided
apparatus for suspending junction boxes in a suspension ceiling,
such as disclosed by LoNigro, in U.S. patent No. 3,597,889,
and by LeManquais, in U.S. patent No. 1,966,451, the structures
disclosed therein allowing the mounting of lighting fixtures
and other appliances of varying weight, size and shape. It is,
therefore, to be understood that the concept of providing
structure in a suspended ceiling framework capable of providing
balance support means for electrical lighting fixtures is not
new in the field of endeavor under consideration.
Description of further prior art structures adaptable
to similar purpose is provided in U.S. patent No. 3,597,889.
The present invention provides structure similar to
that disclosed in U,S. patent No. 3,597,889, the structure so
disclosed being improved by forming the straight, substantially
flat-faced median portion of the supporting bar with twisted
portions near proximal end portions thereof to add strength
and torsional stability to the bar. In effect, the median
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portion of the prior art supporting bar, major planar surfaces
of which are substantially horizontally disposed in said prior
art supporting bar, are turned 90 degrees so that the major
planar surfaces of the bar are substantially vertically dis-
posed, the median portion o~ the supporting bar remaining
aligned in a substantially straight line with~the proximal
end portions of the bar.
The invention, therefore, provides a prefabricated
adapter apparatus which comprises a length of flat-faced strap
iron which is of one-piece construction and provides a sub-
stantially rigid supporting bar. This bar has a median portion,
the axis of which is pivoted or twisted relative to the end
portions thereof as aforesaid, the bar being sufficiently rigid
to accommodate a slotted hanger clip, that is, a clip which is
fastened to or otherwise carried by a slotted top wall of a
conventional junction box. The respective end portions of the
strap iron or bar are provided with downwardly offset bent
portions. Each bent portion is L-shaped and has a horizontal
portion united with a right angularly disposed downwardly
opening U-shaped terminal end portion which defines a bar mount-
ing and attaching hook. The respective hooks are fitted over
the vertical flanges of customary T-irons which are employed
in a ceiling frame. The outer leg or bill portion of the hook
is equipped with a setscrew which permits the hook to be securely
anchored, In particular, the body portion of the strap iron or
bar is of a predetermined length and is straight from end to
end, said body portion serving to accommodate a conventional
cup-shaped junction box along the median portion thereof, par-
ticularly, a junction box which has a top wall provided with a
U-shaped clip. The clip has opposed spaced parallel legs which
project upwardly through slots provided in the top wall of the
box. The projecting portions of the legs have regis~ering
slots which are adapted to slidingly receive portions of the
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supporting bar medially of its length in a manner to permit
a junction box to be shifted to assume and maintain a pre-
determined position.
In summary of the above, therefore, the present
invention may be seen as providing an openwork suspended
ceiling frame strl.cture embodying at least a pair of spaced
parallel coplanar inverted T-iron frame members, an improved
fixture support adapter unit adapted to bridge the space
between coacting portions of the respective T-iron frame
members, the adapter unit consisting of an elongated bar-like
body having two major parallel planar surfaces and two minor
parallel surfaces oriented transversely of the major surfaces,
the body having a median portion, the major planar surfaces
of which are vertically oriented, the major planar surfaces
of end portions of the body adjacent the median portion being
oriented horizontally, the median portion being thereby twisted
edgewise relative to remaining portions of the body and further
wh~rein e~d portions of the unit comprise U-shaped hook members
having inner and outer legs joined at upper ends thereof by a
connecting bight portion, the hook fitting onto a vertical
flange portion of the frame member.
Figure 1 is a perspective view illustrating a pair
of parallel spaced inverted T-irons such as are used to form
an openwork or grid suspension ceiling frame, the improved
attachable and detachable prefabricated
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adapter structure of the invention being shown extending between the T-irons;
Figure 2 is a detail sectional view taken along line 2 -2 of Fig. l;
Figure 3 is a detail sectional view taken along line 3--3 of Fig. l;
and
Figure 4 is a detail plan view of a portion of the structure shown
in Fig. 1.
Referring now to the drawings and particularly to Fig. 1, a fixture
support adapter unit is seen generally at 10 to be mounted to a conventional ~ -
suspension ceiling frame structure, the frame struc~ure being comprised of a
pair of parallel spaced lnverted T-iron frame members 12~ The paired spaced
parallel coplanar frame mem~ers 12 are of conventional inverted T-shaped con-
struction and are generally referred to as T-irons, the frame members 12 hav-
ing horizontal flanges 14 and a vertical or upstanding flange 16. The adapter
unit 10 i6 detachably and adjustably secured to the vertical flange 16 as will
be described hereinafter. The adapter unit 10 i5 seen to comprise a single
length of flat~faced strap metal which forms a body 18. End portions 22 are
identical in structure and are configured to fit over the vertical flanges 16
of the frame members 12. Each end portion 22 has a vertical depending por-
tion 26 and a horizontal depe~ding portion 28 which, when installed, rests
atop or adjacent the upper surface of a ceiling panel or block of conventional
configuration. The terminal end of the hori~ontal depending portion 18 ls - -
joined with an inverted U-shaped hook 30, the hook fitting revably over the
vertical flange 16. An outer leg of the hook, which i9 often referred to as
the bill portion, i8 provided with an aperture through which a setscrew 32
extends to secure the hook 30 conveniently and accessibly in place on the
frame member 12.
The body 18 of the adapter unit 10 takes ~he form of an elongated
bar having major planar surfaces 21, a median portion 20 of the body 18 hav-
ing the major planar surfaces 21 oriented with said surfaces 21 disposed
vertically while the portions of the surfaces 21 adjacent the end portions 22
are oriented horizontally. Therefore, the bar-like body 18 can be said tc be
twisted at 24 and 25 to form the median portion 20, the planar surfaces 21 of
the median portion 20 being turned at a 90 degree angle to the major planar
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surfaces of adjacent portions of the body. A conventional junction box (not
shown) can be supported on the median portion 20 in a known manner, a clip 36
having vertically extending legs 38 extending through a slot in an upper wall
of a conventional junction box, the legs 38 having vertical slots 40 formed
therein through which the median portion 20 of the body 18 is received. The
clip 36 can be moved along the median portion 20 and positioned as desired
thereon. An assembly screw 44 can be used to hold a conventional threaded
nipple 42 to the underside of the clip 36, the nipple 42 acting to maintain
the junction box in place.
A junction box attached to the support adapter unit 10 can be slid
freely along the entire length of the median portion 20 of the bar-like body
10 and can be secured by tightening of the screw 44 at any selec~ed position,
thereby providing adjustability in the placing and centering of the junction
box and thus the fixture connected thereto. A fixture thereby mounted cannot
be pushed upwardly or out of place since the junction box to which it ls con-
nected is secured on the body 18, the body 18 being secured at both ends to
the T-iron frame members 12. Thus, the fixture is virtually immovable in
spite of the fact that ceiling panels forming the suspension ceiling can be
pushed out of place in the usual ~anner by a touch of the finger.
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