Modular construction for radiant panel

Individual elongated radiant heat panel modules are secured together along their side edges to form a panel; and a plurality of transverse spaced-apart stiffeners are connected at a plurality of connection sites across the panel back to stiffen the panel and hold it fast. Each stiffener is fixedly connected to the panel at only one fixed connection site whereby to block relative movement between the stiffener and panel at said site; and each stiffener is additionally connected to the panel at a plurality of connection sites by spring clamps which hold the panel and modules thereof flat against the stiffener while permitting limited relative movement thereat between said stiffener and said panel. The connection sites on the stiffener are spaced therealong while the connections to the panels are at or adjacent the side edges of the individual modules. Adjacent individual modules are fixed to each other.

BACKGROUND OF THE INVENTION 
This invention relates to radiant metal panels fabricated by assembly of 
extruded modules, and in particular to ways and means for securing the 
assembly together while accommodating thermally-induced dimensional 
changes such as caused by temperature variation. 
It is common to make panels by securing together several adjacent elongated 
modules. Tubes or pipes are secured to the back of the modules to conduct 
heat exchange medium therepast. Panels of this type are used in highly 
visible areas, such as meeting rooms, offices, and the like, where it is 
necessary that the face of the panel be and remain flat and neat appearing 
under all conditions. At the same time, for many reasons, the panel 
members should be of high heat conductivity and as light weight as 
possible. 
In a usual construction, individual modules are of tongue and groove 
design, with a tongue along one side edge and a complemental groove along 
the other edge. Adjacent modules are fitted together, the grooves of one 
being crimped onto the tongue of another to hole them in assembled 
position. A plurality of spaced-apart rigid stiffeners are then secured 
transversely across the back of the panel and fixed individually to all 
the several modules to hold them securely as a flat rigid panel. The 
stiffener is also a straightener which contacts the modules in a straight 
line. Such construction, although widely used, does have some drawbacks. 
This is so because when all modules are fixed to the stiffener as in the 
prior construction, there is no relative movement possible between modules 
and stiffener, hence the panel cannot accommodate thermally-induced 
dimensional variations. When heat causes the modules to expand, the 
individual panel modules, being fixed to the stiffener, will buckle or 
fracture connections to the stiffener and/or cause the stiffener to bend. 
The stiffeners cannot be omitted because without them the panel will 
simply not lie flat. 
SUMMARY OF INVENTION 
It is the primary object of the present invention to provide a radiant heat 
panel that includes a plurality of side-by-side elongated modules and is 
adapted to accomodate thermally-induced transverse expansion and 
contraction of the individual modules. 
Another object is the provision, in a panel of the type described, of a 
novel spring-clamp for connecting the modules to the stiffeners. 
The foregoing and probably other objects of the invention are achieved in a 
panel of the type described by an arrangement whereby each stiffener is 
fixedly connected to the panel at only a single preselected site on the 
panel and stiffener thereby blocking relative movement between the parts 
at that site. Then, the stiffener is connected to the panel at additional 
sites, spaced along said stiffener across said panel, by clamps which 
permit limited relative movement between said stiffener and modules of the 
panel. In the preferred embodiment of the invention, the clamps are spring 
clamps which urge the stiffener toward and hold it against the panel 
modules. 
In order that the invention may be more readily understood and carried into 
effect, reference is made to the accompanying drawings and descriptions 
thereof, which are offered by way of example only and not in limitation of 
the invention, the scope of which is defined by the appended claims, 
including equivalents embraced therein, rather than any description 
thereof.

DETAILED DESCRIPTION OF THE INVENTION 
With initial reference to FIG. 1, the assembled panel 11 is formed from 
adjoining individual modules 12, each of which is an extrusion of modest 
width, typically 5 to 9 inches. The modules have upwardly facing channels 
13 along each edge. Each channel has two flanges 14 extending inwardly 
toward one another from the top edges of its sidewalls. A tongue 16 is 
formed along one side edge of the module and a complemental groove 17 is 
formed along its opposite edge. A hollow forms a conduit 18 on the module 
to accept a copper pipe, not shown. 
For assembly, a plurality of modules are pressed together with tongues 16 
received in respective grooves 17. A transverse stiffener 21 spans the 
panel across the backs of the modules. Cutouts 20 in the stiffener bottom 
and sides accept the conduits 18 so the stiffener 25 bottom will rest on 
the channel flanges 14 to maintain the panel flat. 
In the preferred embodiment, two precisely located holes 22 in the flat 
bottom 25 of the stiffener near its center overlie and register with nuts 
23 received in the channels 13 of adjacent modules 12. Screws 24 are 
directed through the holes 22 into the nuts and tightened snugly to 
rigidly fix the two central modules to the stiffener and thus to each 
other. This is the important fixed connection site at which no relative 
transverse motion can occur between the stiffener and panel or its 
modules. 
The remaining connection sites on the stiffener are at the slots 27 and are 
sites where spring clamps are used to hold the stiffener to the panel yet 
allow relative movement. They may be referred to specifically as non-fixed 
connection sites or clamp sites. 
A plurality of spring-clamps are provided. To this end, the rigid stiffener 
includes a plurality of slots 27 in the bottom located directly above and 
transverse to adjacent pairs of edge channels 13 of adjacent modules 12. A 
full spring clamp member 28 is aligned over the slot 27 and fastened to 
the modules by screws 24 tightened into the nuts 23 received in respective 
module channels 13. By this means the central section of the spring clamp 
28 is fixed to the modules at the channel flanges 14. Thus, the same 
central spring section is a link fixing the modules to each other. The 
spring 28 is longer than the slot 27 so that its free ends extend past the 
ends of the slot and over the bottom of the stiffener. The spring 28 is 
also narrower than the slot 27 so rests on the flanges 14. The result is 
to establish a spring clamp operable to urge and hold the stiffener 
against the modules yet permit limited relative motion between the 
stiffener and the underlying modules. The screw holes through the spring 
clamp 28 are spaced apart the same distance as that between the holes 22 
in the stiffener. This is the same spacing as between channels 13 of 
adjacent modules. The spring members 28, nuts 23, screws 24, and flanges 
14 on the channel 13 combine to secure adjacent modules together in fixed 
relationship and to clamp the resulting panel against the stiffener 21. 
In the illustrated embodiment, the basic non-fixed or slidable clamp 
connection is achieved by the spring clamp 28 urging the flat stiffener 
bottom 25 firmly against the channel flanges 14. In this arrangement, the 
spring may be considered as clamping the stiffener against the panel at 
the modules 12 even though the stiffener is never literally clamped 
between the spring and module. The lateral force, as produced by thermal 
expansion of a module, will result in relative movement between the 
stiffener and module. In this invention, when the modules expand, the 
increased width is accommodated by the spring clamp 28 yet the individual 
panel modules are maintained flat against the stiffener. 
FIG. 2 illustrates a half size spring clamp member 29 used at the end of 
the stiffener adjacent an outer edge of the panel. A nut 23 is located in 
the outer channel 13 beneath an open ended slot 27 of the stiffener. The 
half size spring 29 is located above the stiffener to extend past the slot 
27 and over the stiffener bottom. A screw 24 passes through the spring 29 
and is screwed tightly into the nut 23 to urge the spring against the 
stiffener bottom. 
The relative sliding movement between the individual panel modules and the 
stiffener is very slight, perhaps 1/32 to 1/16 of an inch for a full three 
foot panel of four nine inch wide modules. The spring clamp connections of 
the invention accommodate such movement. 
It will be apparent to those skilled in the art that each panel assembly 
utilizes a plurality of transverse, parallel, spaced apart stiffeners and 
that, on any given panel, all stiffeners will be fixed to same modules by 
the same connection pattern. 
As is usual, the exposed front side of the panel will be suitably finished. 
Copper tube will be fitted into the conduits 18, and the panels suitably 
connected and hung. 
My invention is adapted for panel assemblies comprising a plurality of 
panel modules. Although the illustrated embodiment shows the sole fixed 
connection to be near the transverse center of the panel, said sole fixed 
connection may be at other locations such as the outer panel side edge or 
adjacent any joint between modules. The basic requirement is that there be 
only one fixed connection between each stiffener and panel and that the 
remaining connections be of non-fixed design, such as clamps, that permit 
relative movement as described. 
Having thus described my invention, that which I desire to secure by 
Letters Patent is defined by the following claims.