Note: Descriptions are shown in the official language in which they were submitted.
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1 o THERMOSTATICALLY CONTROLLED ELECTRIC
HEATING APPARATUS
DESCRIPTION
The present invention relates to a thermostatically controlled
electric heating apparatus, such as for instance of the kind used in
conjunction with radiators or similar heaters.
These electric heating apparatuses are generally known to usually
comprise a cartridge-type electric heating element that is provided of
an outer threading in order to be capable of being installed by being
screwed on in a support body, which may for instance be constituted
by a radiator.
In correspondence of a head-side end portion of such an electric
heating element, from the element itself there are protruding
substantially axial electric terminals that are connected, for example
by means of fast-on connection devices, to complementary electric
contacts that are provided in a temperature control device adapted to
be connected to the power supply. In particular, this temperature
control device has a substantially box-like structure formed by two
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appropriately shaped half-shells, which are then coupled together, i.e.
against each other so as to clamp, upon said heating element having
been screwed on in its support body, the head-side end portion of the
heating element itself therebetween.
These prior-art solutions, however, are associated with a number of
drawbacks. In particular:
- they are time and labour intensive and, therefore, expensive to
assemble on an industrial scale;
- the assembly itself must be carried out by appropriately skilled
personnel with the use of appropriate tools, so that it must be
completed at the factory, which practically means that the final user
must necessarily be supplied with a duly pre-assembled unit
comprising the heating element, the temperature control device and
the support body;
- such a pre-assembled unit turns necessarily out as being
undesirably bulky, so that it gives rise to problems related to storage
and transport;
- during transport and/or handling of the pre-assembled units, the
temperature control devices are subject to easily occurring
breakdowns, owing to their being provided with a not so much robust
plastic structure;
- even maintaining and/or repairing the thermostatically controlled
electric heating apparatuses themselves imply performing a number of
undesirably complicated, awkward and expensive operations, which
must anyway be carried out by adequately skilled personnel.
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In conclusion, traditional solutions turn out as being fully
unsatisfactory.
It therefore is a purpose of the present invention to provide a
thermostatically controlled electric heating apparatus that is effective
in substantially minimizing the above-mentioned drawbacks of prior-
art solutions.
Namely, it is a purpose of the present invention to provide a
thermostatically controlled electric heating apparatus, which is capable
of being quickly and conveniently assembled even by unskilled
personnel and, therefore, is capable of also being assembled directly in
the field, without having to necessarily be pre-assembled at the factory,
i.e. the original manufacturing site.
Another purpose of the present invention is to provide a
thermostatically controlled electric heating apparatus of the above
cited kind, which is capable of being stored, handled, transported and
possibly even repaired in a safe, reliable and convenient manner, while
minimizing the risks for component parts to suffer accidental
breakdowns.
According to the present invention, these aims are reached in a
thermostatically controlled electric heating apparatus embodying the
characteristics as recited in the appended claims.
Anyway, features and advantages of the present invention can be
more readily understood from the description that is given below by
mere way of non-limiting example with reference to the accompanying
drawings, in which:
- Figure 1 is a partially cross-sectional and partially see-through
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exploded side view of a preferred embodiment of the present invention;
and
- Figures 2 is a cross-sectional, enlarged-scale view of a pair of
component parts illustrated in Figure 1, in an assembled state thereof.
With reference to the Figures, the thermostatically controlled
electric heating apparatus according to the present invention mainly
comprises an electric heating element 1 of the cartridge type, which
extends along a main axis 2.
At a head-side end portion 3 thereof, said heating element 1 is
provided, in a per se known manner, with electric terminals 4
protruding therefrom in a substantially axial direction, i.e. parallel to
each other and adjacent to said main axis 2.
Said electric terminals 4 are preferably of the male type, comprising
respective metal tabs featuring an adequate mechanical strength , and
are preferably surrounded by a cylindrical protection portion 5
protruding axially. This protective portion is provided with one or more
axial projections 15 diametrically opposing each other, whose role will
be explained in greater detail further on.
Close to the head-side end portion 3 thereof, the electric heating
element 1 is provided with a threaded portion 6, by means of which it
is capable of being assembled its intended site of use by being screwed
on in a support body 7, which may for instance be formed by a
radiator. In any case, the heating element 1 can be screwed on in the
support body 7 thereof in an extremely simple manner, while of course
taking any casual angular position around the main axis 2. In other
words, upon the heating element 1 having been screwed on, the
electric terminals 4 thereof end up by taking a casual angular
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orientation.
On the other hand, the electric terminals 4 of the heating element 1
must be connected to complementary electric contacts 8 provided in a
temperature control apparatus that is schematically indicated at 9 in
the Figures.
This temperature control device 9 may comprise electronic and/or
electromechanical control and adjustment means of a per se known
type (not shown in the Figures), and is adapted to be connected to the
power supply via conductor leads 10. In any case, the temperature
control device 9 has a substantially box-like structure that must be
installed, in a juxtaposed arrangement with respect to the heating
element l, with a definite orientation. It can be readily appreciated
that this definite orientation is in contrast with the afore cited casual
angular orientation of the heating element 1, so that it is not suited to
allow for a simple mutual coupling of the heating element itself and the
device 9.
According to a feature of the present invention, this problem is
overcome by arranging the electric terminals 4 or the contacts 8 in
correspondence of angular adaptation means 11 that enable the
heating element 1 and the temperature control device 9 to be
mechanically and electrically coupled together in an axial direction,
whereby any possible angular displacement of said electric terminals 4
and said complementary contacts 8 with respect to each other is
automatically compensated for.
In the example being described here, in particular, the
complementary contacts 8 are attached inside said angular adaptation
means 11, wherein these means are substantially in the shape of a
cup-like member that is mounted, in a freely rotatable manner about
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the axis 2, in a corresponding receptacle provided within the
temperature control device 9. The capability of said cup-like member
11 to freely rotate with respect to the device 9 is ensured, to a
sufficient purpose-fitting extent as this will be better described further
on, by the flexibility of the conductor leads 10 that substantially extend
in a slack manner from said contacts 8 to the outside of said device 9
(through a specially provided opening 12).
The cup-like member 11 is oriented with the open end portion 13
thereof facing outwards and is preferably so sized as to be able to
accommodate the cylindrical portion 5 of the heating element 1, so as
to bring about a mutual mechanical coupling of the component parts 1
and 9 constituting the thermostatically controlled electric heating
apparatus of the present invention.
The cup-like member 11 comprises at least an impression 14, or
similar recess, which extends axially from the edge 13 with at least an
inclined-plane portion 16 that joins with an axial portion 17 adapted to
slidably receive an axial projection 15 of the heating element 1.
In a preferred manner, on the cup-like member 11 there are
provided two impressions 14, or similar recesses, that are so arranged
as to diametrically oppose each other, in which each one of said
impressions is adapted to slidably cooperate with a respective axial
projection 15 of the heating element 1, and each one of said
impressions further comprises two convergent inclined planes 16,
which are provided for centering purposes and join with an axial
portion 17.
In any case, the angular positions of the various elements are such
that, when the projections 15 of the heating element are aligned with
the axial portions 17 of the impressions 14, the electric terminals 4
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come to lie in alignment with the complementary contacts 8, too.
In a preferred manner, in correspondence of the edge 13 thereof,
each impression 14 extends for an angular length of 90°, so that, when
S the device 9 (which is oriented in a manner responding to installation
needs) is brought axially near the heating element 1 (which is oriented
in a casual manner, as this has already been explained above), each
impression 14 will reliably and certainly be engaged by a
corresponding projection 15.
In the quite probable case that, at first, the terminals 4 are
angularly staggered or displaced with respect to the contacts 8, each
projection 15 will slidably engage an inclined plane 16 of a
corresponding impression 14. As a result, during a first axial length
along which the heating element 1 and the device 9 are brought close
to each other for coupling, the interaction of the projections 15 and the
inclined planes 16 with each other causes the cup-like member 11 to
rotate about the axis 2 until the projections 15 come to lie in alignment
with respective axial portions 17 of the impressions 14. As this has
already been explained above, this is the geometrical condition in
which also the axial alignment of the electric terminals 4 with the
complementary contacts 8 takes place. On the other hand, the relative
sizing of the component parts will be calculated in such a manner as to
ensure that, in this geometrical condition, no coupling is able to come
about between said terminals 4 and adjacent contacts 8 yet.
At this point, as the heating element 1 is further approached to the
device 9 along a subsequent axial length, the projections 15 are able to
slide along the axial portions 17 of the impressions 14 and, at the
same time, the electric terminals 4 get inserted on to the
complementary contacts 8, thereby completing an effective electric and
mechanical connection of said terminals with said contacts, as well as
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of the whole heating element 1 and the temperature control device 9.
As already hinted above, the mechanical attachment of the devices
1 and 9 to each other is advantageously strengthened by the
geometrical coupling, i.e. the fitting of shapes, of said cylindrical
portion 5 in the cup-like member 11.
In all cases, it can be readily appreciated that said cup-like member
11, as arranged between the heating element 1 and the temperature
control device 9, constitutes a very simple and effective member that
enables the relative angular position of the parts that must be coupled
electrically and/or mechanically with each other to be adapted
automatically.
This most advantageously enables the heating element 1 and the
temperature control device 9 to be manufactured separately, i.e. as
separate assemblies, under resulting benefits in terms of storage and
transport advantages. Furthermore, the final assembly of the whole
thermostatically controlled heating apparatus can be completed
quickly, conveniently and reliably even by unskilled personnel. All it
takes is in fact screwing the heating element 1 on in the support body
7 in an angularly casual position thereof and, then, coupling the device
9 axially to the end portion 3 of the same heating element.
It will of course be appreciated that the thermostatically controlled
electric heating apparatus that has been described above by mere way
of example, may be the subject of a number of modifications without
departing from the scope of the present invention.
So, for instance, the angular adaptation member 11 may be
rotatably mounted on the heating element 1, rather than the device 9.
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In addition, on the heating element 1 there may be provided female-
type contacts 8, whereas complementary male-type terminals 4 would
in this case be provided in the angular adaptation member 11.
There may be also provided a safety feature constituted by a
peripheral groove 18, or the like, provided on the cup-like member 11
and adapted to cooperate with a fixed check means 19 provided on the
box-like member 9. This groove 18 has a limited angular extension, e.g.
90°, defined by opposed shoulders 20 that are adapted to act as
respective angular stop means when they come to abut against said
check means 19. This arrangement 18-20 is effective in preventing
excessive accidental torsional strains from being imposed to the flexible
conductor leads 10, thereby ensuring the proper operating state
thereof.
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