Refrigeration circuit

Abstract

A refrigeration circuit ( 3 ) for household appliances comprises a compressor ( 4 ) suitable for compressing a predetermined cooling fluid and for allowing the circulation thereof within said circuit ( 3 ), a first heat exchanger ( 5 ) or condenser in fluid communication with the compressor ( 4 ) for allowing the cooling and the consequent condensation of the cooling fluid going through, and a second heat exchanger ( 7 ) or evaporator in fluid communication with the first exchanger ( 5 ) through a circuit with a special device ( 6 ) suitable for decreasing the pressure of the cooling fluid at a space ( 2 ) to be cooled (normally inside the refrigerator). The second exchanger ( 7 ) allows the cooling fluid to evaporate, absorbing heat, thus cooling the space ( 2 ) and returning through the tubing ( 17 ) to the compressor ( 4 ). The cooling fluid circulates from the compressor ( 4 ) towards the first exchanger ( 5 ), from the latter towards the second exchanger ( 7 ) and then returns to the compressor ( 4 ) for a subsequent cycle. At least one of the heat exchangers ( 5, 7 ) comprises a plastic tubing ( 9 ), at least a portion whereof exhibits such corrugated profile as to impart flexibility thereof and/or increase the thermal exchange surface.

1 - 53 . (canceled) 
   
   
       54 . Refrigeration circuit ( 3 ) for household appliances, in particular household appliances for cooling such as refrigerators, freezers and the like, comprising:
 at least a first heat exchanger ( 5 ), suitable for being placed in fluid communication with a compressor ( 4 ), for allowing the cooling of a cooling fluid substantially in liquid phase in crossing;   at least a second heat exchanger ( 7 ) in fluid communication with said first exchanger ( 5 ) and active at a space ( 2 ) to be cooled, said second exchanger ( 7 ) allowing the cooling fluid at least partly in gaseous phase to absorb heat cooling said space ( 2 ), the cooling fluid circulating from the first exchanger ( 5 ), towards the second exchanger ( 5 ) and thus being directable to a compressor ( 4 ) for a subsequent cycle; and   preferably a lamination device ( 6 ) arranged between said first ( 5 ) and second ( 7 ) heat exchanger for generating an expansion of said cooling fluid, at least one of said first ( 5 ) and second ( 7 ) heat exchanger comprising at least one flexible tubing ( 9 ),   
     characterised in that at least a portion of said tubing ( 9 ) is a flexible corrugated tubing adaptable to be arranged according to a plurality of different configurations by simply bending tubing ( 9 ) without intervening plastically and irreversibly deforming tubing ( 9 ) itself. 
   
   
       55 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that said tubing ( 9 ) is made of a material not permeable to said cooling fluid circulating in said tubing ( 9 ), preferably a material not permeable to cooling fluids selected from the group comprising HC, HFC or mixtures thereof. 
   
   
       56 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that said tubing ( 9 ) comprises at least one layer (S 1 ) of plastic material, preferably polyamide and even more preferably polyamide 6-6 or polyamide 6-12. 
   
   
       57 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that said tubing ( 9 ) is made of a material not permeable to humidity to prevent external humidity from penetrating in said tubing ( 9 ) containing said circulating cooling fluid. 
   
   
       58 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that said tubing ( 9 ) comprises at least two superimposed layers (S 1 , S 2 ) of different materials, preferably both plastic materials, a first layer (S 1 ) of a material impermeable to the cooling fluid and/or to incondensable gases, a second layer (S 2 ) impermeable to humidity. 
   
   
       59 . Refrigeration circuit ( 3 ) according to  claim 58 , characterised in that said first layer (S 1 ), preferably external, is made of a material selected from the group comprising polyamides 6; 6-6; 6-12; 11; 12 and the respective copolymers, preferably polyamide 6-6 or polyamide 6-12, and that said second layer (S 2 ), preferably internal, is made of a material selected from the group comprising olephinic copolymers, low density polyethylene modified with maleic anhydride and polypropylene, preferably modified with maleic anhydride, type BYNEL 4206 by DuPont. 
   
   
       60 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that said tubing ( 9 ) is defined by at least two, preferably a plurality of, modular tube segments connected to each other by respective junction elements for obtaining a fluid-dynamic continuity between said tube segments. 
   
   
       61 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that at least one of said heat exchangers ( 5 ,  7 ) is entirely defined by said tubing ( 9 ), said tubing ( 9 ) being in particular entirely provided with such corrugated profile as to impart flexibility thereto. 
   
   
       62 . Refrigeration circuit ( 3 ) according to  claim 54 , characterised in that at least one of said heat exchangers ( 5 ,  7 ) is entirely defined by said tubing ( 9 ), said tubing ( 9 ) consisting of portions of rectilinear tube spaced by portions of tube having corrugated profile so as to impart flexibility thereto for example in portions where it is necessary to make the bending zones, keeping the other zones stiff and self-supporting. 
   
   
       63 . Circuit according to  claim 54 , characterised in that the tubing ( 9 ) exhibits a non-circular cross section and comprises at least a portion ( 44 ), for example flat, suitable for coupling with a surface of a household appliance at least partly counter-shaped, for example flat, to said portion ( 44 ). 
   
   
       64 . Refrigeration circuit according to  claim 54 , characterised in that a wall thickness (S) of the tubing ( 9 ) is comprised within a range between 0.3 mm and 2 mm and preferably between 0.6 mm and 1.2 mm. 
   
   
       65 . Circuit according to  claim 58 , characterised in that the thickness of the first layer (S 1 ) of material impermeable to the cooling fluid is comprised between 60% and 80% and preferably it is about 70% of the total thickness (S) of the tubing ( 9 ), the thickness of the second layer (S 2 ) of material impermeable to humidity is comprised between 20% and 40%, and preferably it is about 30% of the total thickness (S) of the tubing ( 9 ). 
   
   
       66 . Refrigeration circuit according to  claim 65 , characterised in that the thickness of the first layer (S 1 ) is comprised between 0.2 mm and 0.4 mm, the thickness of the second layer (S 2 ) being preferably comprised between 0.4 mm and 1 mm. 
   
   
       67 . Circuit according to  claim 54 , characterised in that the tube thickness ( 10 ) of the first exchanger or condenser ( 5 ) is such as to allow a burst resistance of 36 bar, and it is preferably comprised between 0.8 and 1.4 mm, preferably with maximum outer diameter of 7 mm. 
   
   
       68 . Circuit according to  claim 54 , characterised in that said tubing ( 9 ) exhibits a maximum outer diameter (Dmax) comprised between 6 mm and 14 mm and preferably within the range of 8 mm-11 mm. 
   
   
       69 . Circuit according to  claim 54 , characterised in that said tubing ( 9 ) of the first exchanger or condenser ( 5 ) exhibits a maximum outer diameter (Dmax) comprised between 5 mm and 10 mm and preferably within the range 6 mm-7 mm. 
   
   
       70 . Circuit according to  claim 54 , characterised in that said tubing ( 9 ) is sized for allowing, in standard operating conditions of the circuit, operating at a velocity of the cooling fluid of at least 4 m/sec. 
   
   
       71 . Circuit according to  claim 54 , characterised in that said tubing ( 9 ) is sized for working with inside pressures within a range from 0.3 to 12 bar and preferably in a range of temperatures between −30° and +70° C. 
   
   
       72 . Circuit according to  claim 54 , characterised in that it may comprise a filter ( 18 ), in particular arranged between the first exchanger ( 5 ) and the lamination device ( 6 ), for removing any humidity present in the circuit, said removal being carried out for example by a gel capable of absorbing humidity. 
   
   
       73 . Circuit according to  claim 72 , characterised in that the body of the filter  18  consists of the tube wall ( 10   b ) coming from the first exchanger or condenser ( 5 ), said wall being suitably enlarged, for example during corrugation, to contain the gel so as to create a filter integral with the tube ( 10   b ). 
   
   
       74 . Circuit according to  claim 73 , characterised in that the filter consists of a body obtained by corrugation from the tube ( 10   b ) closed by a connector, for example, welded thereto by ultrasounds or glued, which couples to the capillary ( 21 ).