[0001] The present invention relates to a radiator made of stamped steel plate, particularly
for domestic heating systems.
[0002] More specifically, the invention relates to a radiator made of stamped steel plate
of the type that comprises a plurality of elements arranged side by side; each element
is formed by a pair of oppositely arranged heads, and each head is formed by respective
electrically welded half-shells which are connected by a plurality of pipes, typically
a set of three pipes, which are in turn electrically welded to respective cylindrical
fittings of the heads.
[0003] In known radiators of this type, the heads of each element have cylindrical fittings
for the connecting pipes; these fittings have the same inside and outside diameter
as the pipes, which are butt-joined to said fittings and connected by means of welding
beads formed with various electric welding methods.
[0004] Owing to the limited thickness of the plate used for the heads and the pipes, typically
between 8 and 15 tenths of a millimeter, the positioning of the end of the pipes with
respect to the fittings of both heads is highly critical, since said pipes must be
perfectly axially aligned with the respective fittings essentially to ensure correct
execution and tightness of the electric weld but also for aesthetic reasons, since
an axial offset between the pipes and the respective head fittings, although slight,
can be easily noticed and is perceived as a discontinuity that shows poor workmanship.
[0005] This considerably complicates the processes for mass-production of said radiators,
forcing accurate checks of the gauging of the fittings and of the pipes and of their
mutual positioning, entailing considerable production downtimes, use of specialized
labor, and high production rejection.
[0006] A principal aim of the present invention is to eliminate these and other drawbacks
and to provide a radiator made of stamped steel plate that can be manufactured with
simplified processes that do not require, in particular, accurate checking of the
mutual positioning of the pipes and of the head fittings and are therefore economically
advantageous and adapted for mass-production.
[0007] Within the scope of this general aim, the invention also has the further object of
providing a radiator that has a pleasant aesthetic appearance and does not require
any resumption of the production process after electric welding.
[0008] According to the present invention, this aim, this object, and other important ones
are achieved by providing a radiator made of stamped steel plate having the specific
features stated in the appended claims.
[0009] Essentially, the invention is based on the concept that the pipes used to connect
the heads of each radiator element have a different diameter with respect to the fittings
provided on said heads; in particular, the diameter of the pipes is larger than the
diameter of the head fittings or vice versa; the invention is also based on the concept
of providing the ends of the pipes, or respectively of the fittings, with tapering
circular arc-like coupling regions that provide butt-joining between said pipes and
said fittings.
[0010] The invention will become apparent from the following detailed description and with
reference to the accompanying exemplifying drawings, wherein:
-- figure 1 is a front view of a radiator formed by a set of radiator elements produced
according to the present invention;
-- figure 2 is a sectional view, taken along the plane II-II of figure 1;
-- figure 3 is a sectional view, taken along the plane III-III of figure 2;
-- figure 4 is an enlarged-scale detail view of the joint section referenced by the
circle IV in figure 3;
-- figures 5 and 6 are respectively a sectional view and an enlarged sectional view,
similar to figures 2 and 4 respectively, of a different embodiment that provides the
same advantages.
[0011] In figure 1, the symbol RT designates a radiator, typically for domestic heating
systems, provided by arranging side by side and mutually connecting a plurality of
radiator elements, generally designated by the reference numeral 10.
[0012] Each radiator element 10 is made of stamped steel plate and comprises two heads 11-11'
which are connected by a plurality of pipes, typically a set of three pipes 12, which
are arranged side by side and parallel to each other.
[0013] Each head 11 is formed by respective symmetrical half-shells such as 11a-11b which
are juxtaposed and electrically welded along respective centerlines S. Cylindrical
fittings 13-13' are provided on the heads to connect the ends of the pipes 12, which
are in turn electrically welded to said cylindrical fittings.
[0014] According to the invention and for the specified purposes, the inside and outside
diameters of the pipes 12 are different from the corresponding inside and outside
diameters of the cylindrical fittings 13. In particular, in the embodiment of figures
1 to 4, the inside and outside radii r₁-r₂ of the pipes 12 are greater than the corresponding
radii r'₁-r'₂ of the fittings 13 and differ by an amount that is equivalent to 50
to 90% of the thickness "d" of the plate of the pipes and of the fittings, so that
the pipe 12, by having an inside diameter that is smaller (by 50 to 10%) than the
outside diameter of the fitting 13, cannot be fitted over said fitting.
[0015] In order to facilitate the electrically-welded butt-joining of the pipes 12 to the
fittings 13, the ends of said pipes are provided with tapering circular arc-like connecting
regions 12a (figure 4) that act as an abutment for the end of the respective fitting
13.
[0016] The embodiment of figures 5 and 6, which obviously achieves equal advantages, differs
from the embodiment of figures 1 to 4 in that in this case the outside and inside
diameters of the pipes 112 of the radiator elements 100 are chosen so that they are
smaller than the corresponding outside and inside diameters of the fittings 113 of
the heads 110-110' of said elements.
[0017] In this case, too, the respective outside and inside radii r₁-r₂ of the pipes and
the radii r'₁-r'₂ of the fittings differ by an amount that is 50 to 90% of the thickness
"d" of the plate, so that the outside diameter of the pipe 112 is in any case greater
than the inside diameter of the corresponding fitting 113 to prevent the pipe from
entering the fitting.
[0018] Furthermore, according to this embodiment, the end of each fitting 113 is provided
with a tapering circular arc-like connecting region 113a that acts as an abutment
for the end of the pipe 112.
[0019] The present invention of course cover all embodiments that achieve the same advantages
by using the same inventive concept defined by the appended claims.
[0020] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. Radiator (RT) made of stamped steel plate, particularly for domestic heating systems,
which comprises a plurality of radiator elements (10), each element being formed by
a pair of oppositely arranged heads (11-11') that are connected by a plurality of
pipes (12), and wherein each head, formed by oppositely arranged electrically welded
half-shells, is provided with cylindrical fittings (13-13') for the electrically welded
coupling of said pipes (12); characterized in that the pipes (12) that connect the
heads (11-11') have a different diameter with respect to the fittings (13) provided
on said heads.
2. Radiator according to claim 1, characterized in that the pipes (12) that connect the
heads (11-11') have larger inside and outside diameters than the corresponding inside
and outside diameters of the fittings (13) provided on said heads.
3. Radiator according to claims 1 and 2, characterized in that the ends of the pipes
(12) that connect the heads (11-11') have tapering circular arc-like connecting regions
(12a) that act as an abutment for the end of the respective fitting (13).
4. Radiator according to claim 1, characterized in that the pipes (112) that connect
the heads (111-111') have inside and outside diameters that are smaller than the corresponding
inside and outside diameters of the fittings (113) provided on said heads.
5. Radiator according to claim 4, characterized in that the end of each fitting (113)
of the heads (111-111') is provided with a tapering circular arc-like connecting region
(113a) which acts as an abutment for the end of the respective pipe (112).
6. Radiator according to claim 1 and claim 2 or 4, characterized in that the outside
and inside radii (r₁-r₂) of the pipes (12-112) are greater, or respectively smaller,
than the corresponding outside and inside radii (r'₁-r'₂) of the fittings (13-113)
of the heads (11-111) by an amount that is between 50 and 90% of the thickness (d)
of the plate that forms said pipes and said heads.
7. Radiator made of stamped steel plate, particularly for domestic heating systems, according
to the preceding claims and substantially as described and illustrated and for the
specified purposes.