Refrigerator appliance with refrigeration grid provided with eutectic plates

Abstract: A refrigerator appliance is described comprising a cabinet (1) and at least a refrigerating circuit with compressor and condenser and a refrigeration grid (2). Said refrigeration grid (2) extends in length and width inside said cabinet (1) thus defining horizontal shelves (3; 12, 200, 13, 14, 15) that are arranged at a given distance the ones from the others and made up of a cooling coil (4) that is moulded so as to form spaces (20) in which eutectic plates (10, 11) are housed.

Description: The present invention refers to a refrigerator appliance with refrigeration grid provided with eutectic plates, in particular to a freezer. Even more in particular the present invention refers to a household freezer. Generally there are known household freezers, especially vertical type ones, with compartments for the freezing or the preservation of food in which the temperature can vary from approximately -30°C to -18°C. The maintaining of low temperatures in such types of freezer takes place by means of cycles in which there is an almost continuous activation of the compressor of the same freezer and few moments of pause. This determines a considerable energy consumption in such types of freezer that goes against the actual needs of household appliance producers. In fact in view of the European rules as regards energy consumption the same house appliance producers are operating in order to obtain effective solutions with the aim of reducing the energy consumption. In addition the control and the stabilisation of the temperature in various containers of the freezer is difficult even with a continuous activation of the same compressor. EP-A-1 006 324 and WO 01 27551 A show a refrigerator shelf made up of a cooking serpentine and tool elements which form a grid structure with passages into which a container of eutectic mixture is inserted. In view of the state of the art herein described, scope of the present invention is to realise a refrigerator appliance that allows to obtain an energy consumption lower than the known freezers. According to the present invention, such scope is attained by means of a refrigerator appliance as defined in claim 1. Owing to the present invention it is possible to realise a refrigerator appliance that by means of the use of eutectic plate for each shelf of the refrigeration grid allows to obtain cooling compartments for food with a low energy consumption and in addition allows to better stabilise the temperature inside each compartment. The characteristics and the advantages of the present invention will become evident from the following detailed description of an embodiment thereof, that is illustrated as a non- limiting example in the enclosed drawings, in which: Figure 1 is a schematic front view of a vertical freezer provided with a refrigeration grid according to the present invention; Figure 2 is a section view according to line II-II of the freezer in Figure 1; Figure 3a is a top view of a shelf of the refrigeration grid in Figure 1 provided with a first type of eutectic plate; Figure 3b is a section according to line III-III in Figure 3a; Figure 4a is a top view of a shelf of the refrigeration grid in Figure 1 provided with a second type of eutectic plates; Figure 4b is a section according to line IV-IV of the shelf in Figure 4a. With reference to Figure 1 a vertical freezer is shown comprising a cabinet 1 and a refrigeration grid 2 according to the present invention. The refrigeration grid 2 is arranged along the entire width and the length of the cabinet 1 so as to define horizontal shelves 3 that are arranged at a certain distance the ones from the others and made up of a cooling coil 4. Such shelves 3 are transversally connected the ones with the others by means of rods 5 and 6 that are transversally welded below and above the cooling coil 4 and that are fastened to the side walls of the freezer by means of supports 7. The cooling coil 4 of the shelves 3 forms external folds 8 with a small length of coil and folds 9 with a greater length of coil so as to create appropriate housings 20 that are suitable to receive eutectic plates 10 of a first type that are arranged horizontally, as shown in Figures 3a, 3b. Such eutectic plates 10 are removably fastened to the cooling coil 4 of every shelf and precisely they are connected with the folds 9 so as to occupy a space almost equal to one time and a half the housing 20. The plates 10 are coupled to the coil 4 in order to have considerable contact points both with the same coil 4 as well as with the rods 5 and 6 that are welded to the coil 4 so as to facilitate the thermal exchange. Such eutectic plates 10 have a small thickness but wide lateral surfaces, they are made up of a container generally made of plastic material and they contain an amount of eutectic solution of approximately 0.6 litres. In the cabinet 1 besides the shelves 3 with eutectic plates 10 shelves 3 are also present that are provided with eutectic plates 11 of a second type that are smaller than the eutectic plates 10 and inserted horizontally each one in every housing 20 of the folds 9 of the coil 4 in an extractable way, as shown more in detail in Figures 4a, 4b. Such eutectic plates 11 are coupled to the coil 4 too, in order to have considerable points of contact with it and with the rods 5 and 6 that are welded to the coil 4 and they have a smaller extension of the lateral surfaces. Such plates 11 are made up of a container that is generally made of a plastic material and they contain an amount of eutectic solution of approximately 0.14 litres. The refrigeration grid 2, that is part of a refrigerating circuit (not visible in the figures) comprising an opportune compressor and a condenser, allows to have shelves, each having equal temperature, at various temperatures, and precisely at increasing temperature from the top towards the bottom in cabinet the 1 of the freezer. Therefore it is possible to have shelves 12 to deep freeze food with temperature at -30°C, shelves 200 for quick freezing with temperature at -26°C, medium freezing shelves 13 with temperature at -22°C, storage shelves 14 with temperature at - 18°C. In addition it is also possible to have at least one shelf 15 at differentiated and sectorial eutectic temperature on a same shelf 3 by using eutectic plates 10, 11 at a different temperature on the same shelf 15. The shelves provided with eutectic plate 10, 11 are arranged vertically at a given distance the ones from the others so as to define respective containers 40-45 for the cooling of foods inside the cabinet 1. Such containers 40-45 are closed by respective doors 50-55 while the entire cabinet 1 is closed by a door 60. The eutectic plates 10 and 11 allow a homogenisation of the temperature in the different shelves, that, especially when the compressor is cyclically in pause, allow an increase in times of temperature raise, thus diminishing the energy consumption. In order to obtain the thermal result required by the international specifications it is possible, in the designing stage, to provide the minimum number of eutectic plates 10, 11 that act as a thermal flywheel in the opportune spaces. Preferably the eutectic plates 10 and 11 have various colours according to the type of eutectic solution contained and they can have the temperature directly stamped on the container. The eutectic plates 11, since they are extractable from the housings 20 that are provided in the shelves 3, can be removed and utilised in various ways outside the freezer, for instance in portable refrigerators. Preferably the cooling coil 4 defines housings 20 for eutectic plates 10, 11 with a constant pitch. Preferably each one of the shelves 3 comprises the same number of housings 20 for eutectic plates 10, 11.

Claims: Refrigerator appliance comprising a cabinet (1) and at least a refrigerating circuit with compressor and condenser and a refrigeration grid (2), said refrigeration grid (2) extending in length and width inside said cabinet (1) thus defining horizontal shelves (3; 12, 200, 13, 14, 15) that are arranged at a given distance the ones from the others, said shelves (3; 12, 200, 13, 14, 15) being made up of a cooling coil (4) which forms external folds (8) with a small length of coil (4) and folds (9) with a greater length of coil (4) so as to create housings (20) for receiving eutectic plates (10, 11), said eutectic plates (10, 11) being removably fastened to said cooling coil (4) of each shelf (3; 12, 200, 13, 14, 15). Refrigerator appliance according to claim 1, characterized in that said cooling coil (4) of said shelves (3) defines said housings (20) with a constant pitch. Refrigerator appliance according to claim 1, characterized in that each one of said shelves (3) comprises the same number of housings (20). Refrigerator appliance according to claim 1, characterized in that said eutectic plates (11) are fastened in an extractable way in said housings (20) of said cooling coil (4). Refrigerator appliance according to claim 1, characterized in that said shelves (3; 12, 200, 13, 14) comprise eutectic plates (10, 11) having different colours according to the type of eutectic solutions contained. Refrigerator appliance according to claim 1, characterized in that at least one (15) of said shelves (3; 15) is a differentiated and sectorial eutectic temperature, by using eutectic plates at different temperatures on the same shelf (3; 15) Refrigerator appliance according to claim 1, characterized in that said eutectic plates (11) have a thickness equal to the thickness of the coiling coil (4). Refrigerator appliance according to claim 1, characterized in that said eutectic plates (10) have a thickness greater than the thickness of the coiling coil (4) Refrigerator appliance according to claim 1, characterized in that said eutectic plates (10, 11) is coupled to said cooling coil (4) and to rods (5, 6) that are welded to said cooling coil (4).

Inventors: FUMAGALLI SILVANO, FUMAGALLI, SILVANO
Applicants: CANDY SPA, CANDY S.P.A.
Application year: 2001
Main classification: F25D11
IPC codes: F25D25, F25D16, F25D11