[0001] The present patent application relates to a die-cast aluminium modular radiant element
used in combination with identical elements to form the modular radiators that are
generally used in thermosiphon heating systems.
[0002] As it is known, modular radiant elements consist in a tubular column externally provided
with fins capable of favouring the thermal exchange between the hot water contained
in the radiator and the air that touches the external surface of the radiator.
[0003] An opposed pair of threaded hubs is provided on the top and the bottom of each column.
Connection nipples are screwed onto the hubs to join the adjacent pairs of radiant
elements, as well as to provide communication between the columns of the radiator.
[0004] The purpose of the present invention is to reduce the production cost of the said
die-cast aluminium modular radiant elements, by reducing the thickness of some parts
of the die-cast piece in order to recover aluminium, melt it and reuse it as die-casting
material.
[0005] Since the four hubs of each element need to be threaded, the same machine tool can
be used to internally mill the hubs in order to remove and recover the largest quantity
of aluminium possible, in compliance with mechanical resistance requirements.
[0006] During milling, the very internal section of the hub is enlarged to obtain a diameter
higher than the external threaded opening. The enlargement of the internal ending
section of the hub makes threading easier, since the tapping machine can penetrate
the hub, ending in the enlarged section. The use of a special tool allows for milling
and threading the hub in a sequence, when the tool moves backwards to exit the hub,
after penetrating inside it.
[0007] Finally, another advantage of the hub enlargement is represented by the reduction
of load losses.
[0008] For major clarity the description of the modular radiant element according to the
present invention continues with reference to the enclosed drawings, which are intended
for purposes of illustration and not in a limiting sense, whereby:
- Fig. 1 shows the ending section of the modular radiant element according to the invention,
sectioned with a plane passing through the axis of the two opposed hubs, in which
one hub is milled and threaded and the other hub is in die-cast state.
[0009] With reference to Fig. 1, the modular radiant element according to the invention
traditionally comprises a tubular column (1) externally provided with fins (2) capable
of favouring the thermal exchange between the hot water contained in the radiator
and the air that touches the external surface of the radiator.
[0010] An opposed pair of threaded hubs (3) is provided on the top and the bottom of the
tubular column (1). Connection nipples are screwed onto the hubs to join the columns
of the radiator, as well as to provide communication between them.
[0011] The modular radiant element according to the invention is characterised in that the
threaded opening (3a) of each hub (3) has an internal ending section (3b) with diameter
higher than the threaded opening (3a).
[0012] The section (3b) with increased diameter is obtained by placing the die-cast piece
in a machine tool to mill the internal section (3b) of the hub (3) and then thread
the opening (3a).
1. A die-cast aluminium modular radiant element for thermosiphon heating systems, of
the type comprising a tubular column (1) externally provided with fins (2) and with
an opposed pair of threaded hubs (3) on the top and the bottom, characterised in that
the threaded opening (3a) of each hub (3) has an internal ending section (3b) with
diameter higher than the threaded opening (3a).
