GB2102551A

GB2102551A - Refrigerant circuit for a domestic appliance

Info

Publication number: GB2102551A
Application number: GB08217995A
Authority: GB
Inventors: Marco Cavallini; Luigi Nocivelli
Original assignee: OCEAN SpA
Current assignee: OCEAN SpA
Priority date: 1981-07-20
Filing date: 1982-06-22
Publication date: 1983-02-02
Also published as: IT1137742B; SE8203862L; ES266453U; DK321682A; ES266453Y; SE8203862D0; NL8202683A; DE3225334A1; FR2509847A1; IT8123022A0; BE893743A; CH649372A5

Abstract

The refrigeration circuit of a domestic appliance, such as a refrigerator, freezer or the like is provided with means whereby heat is recovered and used to make hot water available for domestic purposes. The condenser (4) includes, in addition to the normal air-cooled condenser coil (11), a further condenser coil (12) housed in a tank of water (13) which is in close contact with the compressor (3). Valve means (18) are provided which enable the relative flow of refrigerant through the two condenser coils (11, 12) to be controlled whereby to regulate the amount of heat given up to the water in the tank (13) by the further condenser coil (12). <IMAGE>

Description

SPECIFICATION Refrigerant circuit for a domestic appliance The present invention relates to a domestic appliance, such as a refrigerator, freezer or combined refrigerator-freezer, which incorporates a refrigerant circuit including an air-cooled condenser coil and a compressor for circulating a refrigerant fluid around the circuit.

As is known, domestic electrical appliances of this type operate on a refrigerant cycle in which the compressor compresses the refrigerant fluid and delivers it into an air-cooled condenser coil where the fluid gives up heat to the surrounding air; the condensed refrigerant fluid leaving the condenser coil is then reduced in temperature by expansion and fed to an evaporator located in a refrigeration compartment of the appliance. In its passage through the evaporator, the refrigerant fluid takes up heat from the refrigeration compartment, thereby cooling the latter. The refrigeration cycle is completed by the fluid leaving the evaporator being returned to the compressor. The heat inevitably produced by the compressor and given up by the condenser coil is dissipated into the environment with evident wastage of energy.

It is an object of the present invention to provide an improved refrigeration circuit for a domestic electrical appliance which enables at least partial recovery and utilisation of the heat previously allowed to go to waste in prior art applicances.

According to the present invention, there is provided a domestic appliance incorporating a refrigeration circuit which includes a compressor for circulating refrigeration fluid around the circuit, and condenser means arranged to be traversed by the refrigerant fluid after passage through the compressor; said condenser means comprising an aircooled condenser coil, a water tank, means for supplying water to, and drawing off water from, the tank, a water-cooled condenser coil housed in said tank, and valve means for controlling the amount of refrigerant fluid flowing through one said coil relative to the amount of fluid flowing through the other said coil whereby to regulate the quantity of heat given up to water in said tank by refrigerant fluid traversing the said water-cooled coil.In this manner, at least part of the heat rejected by the condenser means of the refrigeration circuit can be recovered and used to heat water for domestic purposes.

Advantageously the said tank is in close contact with the said compressor so that heat generated by the operation of the latter is used to heat the water in the tank.

The refrigeration circuit of a domestic electrical appliance embodying the invention will now be described by way of example, with reference to the accompanying diagrammatic drawings, in which: Figure lisa schematic view of the refrigerant circuit; Figure 2 is a partially sectioned view of a detail of the Figure 1 circuit, and Figure 3 is a schematic view of a variant of the Figure 1 refrigeration circuit.

With reference to the appended drawings, by 1 is generally indicated the refrigeration circuit of a domestic electrical appliance such as a refrigerator.

The refrigeration circuit 1 comprises an electricallypowered compressor 3 carried on a support structure 2 of the appliance, a condenser 4, expansion means in the form of a capillary tube 5, and an evaporator 6, those components being connected together by tubing generally indicated 7. The compressor 3 includes a lower half shell 8 and an upper half shell 9 which are juxtaposed to form the casing of the compressor itself, the lower half shell being provided with feet 10 for fixing the compressor to the support structure 2.

As is standard, the condenser 4 comprises an air-cooled condenser coil 11. In addition, in accordance with the present invention the condenser 4 also comprises a further, water-cooled, condenser coil 12.

In the present embodiment, the further condenser coil 12 is connected in series between the compressor 3 and the air-cooled condenser coil 11 by the section of tubing 7 which runs between these components.

The coil 12 is housed in a tank of water 13. The wall 14 of the tank 13 has a portion 14a which conforms to the shape of the upper half shell 9 of the compressor 3 and is mounted in close contact therewith; the remaining portion 14b of the wall 14 is provided with an insulating layer 15. The water tank 13 has an inlet opening 1 6a for water coming from the mains supply, and an outlet opening 1 6b through which water can be drawn off from the tank, for example, for hygenic or sanitary purposes.

Atube 17 branching from the tubing 7 forms a bypass loop in parallel with the coil 11. Valve means 18, for example an electro-valve, are located at the point of branching of the tubing 7 and the tube 17 upstream of the coil 11. The valve means 18 are controlled by a thermostat, not shown, sensitive to the temperature of the water in the tank 13.

The operation of the Figure 1 refrigeration circuit 1 is described below, with reference to an initial condition in which the water within the tank 13 has been heated, by the heat given up by the further coil 12 and the compressor 3, to a temperature less than the operating temperature of the thermostat. Under these conditions, the valve means 18 serve to direct the refrigerant fluid through the tube 17, so that the air-cooled condenser coil 11 is by-passed and only the condenser coil 12 is operative to condense the refrigerant fluid. As a result, all the heat of condensation is given up to the water in the tank, which goes on being heated as it is drawn off, for example for hygenic or sanitary uses.Now when, due to insufficient water being drawn off, the temperature of the water in the tank 13 reaches and exceeds the operating temperature of the thermostat, the thermostat operates to switch over the valve means 18, rendering the air-cooled condenser coil 11 operative, so that condensation will occur in this coil and thereby ensure continued effective operation of the refrigerant cycle. Immediately the temperature of the water in the tank 13 falls below the operating temperature of the thermostat, due to intervening withdrawals of hot water and/or to natural cooling, the valve means 18 are again switched over to bring the refrigeration circuit 1 back to the said initial condition.

Figure 3 illustrates a variant of the refrigeration circuit, the parts of the Figure 3 circuit which are the same as those of Figures 1 and 2 being indicated by the same reference numerals provided with the index "a"; for the sake of brevity, the description of the function and operation of these parts will not be repeated.

In the Figure 3 variant, the further condenser coil 12a, instead of being placed in the tubing section 7a between the compressor 3a and the air-cooled condenser coil 1 lea, is placed in the tube 17a.

According to this variant, the air-cooled condenser coil 1 la and the water-cooled condenser coil 12a are connected in parallel rather than in series. The general operation of the circuit 1a is substantially the same as that of the circuit 1 with the valve means 1 8a serving to switch over the refrigerant fluid flow between the two coils 1 la, 12a in dependence on the temperature of water in the tank 13.

The described refrigeration circuits allow the energy dissipated during condensation and compression to be at least partially recovered and used to make hot water available, for example, for hygenic or sanitary uses. Furthermore, the provision of the water-cooled condenser coil enables the condensation process to be effected more efficiently and leads to an improved operation of the refrigerant circuit.

Claims

1. A domestic appliance incorporating a refrigeration circuit which includes a compressorforcircu- lating fluid around the circuit, and condenser means arranged to be traversed by the refrigerant fluid after passage through the compressor; said condenser means comprising an air-cooled condenser coil, a water tank, means for supplying water to, and drawing off water from, the tank, a water-cooled condenser coil housed in said tank, and valve means for controlling the amount of refrigerant fluid flowing through one said coil relative to the amount of fluid flowing through the other said coil whereby to regulate the quantity of heat given up to water in said tank by refrigerant fluid traversing the said water-cooled coil.

2. A domestic appliance according to Claim 1, wherein the said tank is mounted in close contact with the said compressor.

3. A domestic appliance according to Claim 1 or Claim 2, wherein the said water-cooled coil is connected in series with the air-cooled condenser coil, and the condenser means further comprises a bypass tube connected in parallel with the air-cooled condenser coil, said valve means being arranged to switch over the refrigerant fluid flow between the air-cooled condenser coil and the bypass tube in dependence on the temperature of the water in said tank.

4. A domestic electrical appliance according to Claim 1 or Claim 2, wherein the said water-cooled coil is connected in parallel with the air-cooled condenser coil, said valve means being arranged to switch over the refrigerant fluid flow between said coils in dependence on the temperature of the water in said tank.

5. A domestic appliance incorporating a refrigerant circuit substantially as hereinbefore described with reference to Figure 1 or 3 of the accompanying drawing.