[0001] The present invention relates to a refrigerator, particularly a domestic refrigerator,
of the type comprising a refrigerator compartment placed below a freezer compartment
and a coolant circuit provided with a capillary tube interposed between a condenser
and an evaporator. The term refrigerator compartment refers here to a compartment
intended for the preservation of foodstuffs at a temperature not below 0°C, while
freezer compartment means a compartment in which the temperature is kept below 0°C.
[0002] Modern domestic refrigerators preferably use evaporators of what is known as embedded
type, i.e. arranged in contact with the outer surface of the liner of the refrigerator
compartment and the freezer compartment and encased in the thermally insulating material
that envelopes the ,compartments. In such refrigerators the water vapour present in
the refrigerator compartment tends to condense on all the cold walls in ratio to the
prevailing thermal gradient. This has the consequence of unwanted condensation of
the vapour, not only on the wall or walls next to which that portion of the embedded
evaporator that is associated with the refrigerator compartment is usually arranged,
but also on other internal walls of the refrigerator compartment. This problem is
observed particularly in refrigerators that have a freezer compartment arranged above
a refrigerator compartment. In fact, for such refrigerators the insulated space interposed
between the freezer compartment and the refrigerator compartment is not always sufficient
to ensure that the upper wall or ceiling of the refrigerator compartment is not at
a lower temperature than the other walls of the compartment. This is unsatisfactory
for the customer because when condensation occurs on the upper wall or ceiling of
the compartment, dripping can be observed, which affects products arranged on the
refrigerator shelves, with obvious consequences in terms of presentation and preservation
of the products themselves.
[0003] The object of the present invention is to obviate said drawbacks, in a simple and
economic manner. According to the invention, this object is achieved in that at least
one portion of the capillary tube is thermally associated with an upper wall of the
refrigerator compartment for the purpose of raising its temperature by reducing the
thermal gradient responsible for the condensation of water vapour on these walls.
[0004] Preferably, in the case of a refrigerator comprising a liner made of plastic material,
which defines the cavity of the refrigerator compartment, the capillary tube is put
in contact with an outer surface of said liner, associated with the upper wall of
the refrigerator compartment.
[0005] Thanks to the temperature of the capillary, placed between the condenser and the
evaporator, which is higher than the temperature of the refrigerator compartment,
a physical condition of the wall is produced, in correspondence with the ceiling of
the compartment, that prevents the phenomenon of condensation, with possible dripping,
on said ceiling.
[0006] Other advantages and characteristics of a refrigerator according to the invention
will become obvious from the following detailed description, provided purely as a
non-exhaustive example, with reference to the attached drawings in which:
- Figure 1 is a diagrammatic view in cross section of a refrigerator according to the
invention, and
- Figure 2 is a diagrammatic perspective view from behind of a refrigerator compartment
liner as used in the refrigerator in Figure 1.
[0007] With reference to the drawings, the reference number 10 illustrates a domestic refrigerator,
as a whole, provided with a refrigerator compartment 10a and a freezer compartment
10b placed above the refrigerator compartment 10a. The refrigerator compartment 10a
is closed off by a liner 12 made of plastic material produced, for example, by thermoforming,
and by a door D. Between said liner and the outer walls of the refrigerator there
is interposed an insulating material 14, for example polyurethane foam.
[0008] The coolant circuit comprises a compressor C, connected to a condenser N placed next
to a rear wall of the refrigerator, said condenser being connected, in turn, via a
capillary tube 16, to an evaporator E having a first portion E' associated with the
freezer compartment 10b and a second portion E. arranged in contact with a vertical
outer surface 12a of the liner 12. The capillary tube is arranged in contact with
a horizontal outer surface 12b of the liner 12, in correspondence with the ceiling
of the refrigerator compartment 10a. To make the capillary tube 16 integral with the
surface 12b of the upper wall of the compartment, an adhesive tape (not illustrated)
is used, preferably mode of aluminium. The capillary 16 is also covered with a sheet
of aluminium 18 made adhesive, to distribute uniformly the heat given off by the capillary.
[0009] Naturally, it is intended that the effects of the present invention extend to models
that achieve the same benefits, exploiting the same, innovative concept. For example,
the solution according to the invention can be used in refrigerators of a type different
from that described and illustrated, for example, refrigerators provided with two
separate evaporators associated with their own independent coolant circuits (two-compressor
refrigerator), or in refrigerators provided with a freezer compartment inside the
refrigerator compartment itself (single-door refrigerators), said refrigerators having
technical characteristics equivalent to the space between refrigerator compartment
and freezer compartment similar to those present in a double-door refrigerator, of
the type illustrated in the drawings.
1. Refrigerator, comprising a refrigerator compartment (10a) placed below a freezer compartment
(10b) and a coolant circuit provided with a capillary tube (16) interposed between
a condenser (N) and an evaporator (E), characterised in that at least one portion
of the capillary tube (16) is thermally associated with an upper wall (12b) of the
refrigerator compartment (10a).
2. Refrigerator according to Claim 2, in which the refrigerator comprises a liner (12)
made of polymeric material defining the cavity of the refrigerator compartment (10a),
characterised in that said capillary tube (16) is placed in contact with an outer
surface (12b) of said liner (12), associated with the upper wall of the refrigerator
compartment (10a).
3. Refrigerator according to Claim 2, characterised in that said capillary tube (16)
is interposed between said outer surface (12b) and a sheet of metal (18) capable of
making the temperature of the upper wall of the compartment more uniform.
4. Refrigerator according to Claim 2 or 3, characterised in that at least one portion
(E'') of the evaporator (E) is arranged in contact with an outer surface (12a) of
the liner, associated with a rear vertical wall of the refrigerator compartment (10a).
