GB2186671A

GB2186671A - A refrigerating and freezing appliance

Info

Publication number: GB2186671A
Application number: GB08603508A
Authority: GB
Inventors: Kenneth Arthur Shone
Original assignee: Thorn EMI Appliances Ltd
Current assignee: Thorn EMI Appliances Ltd
Priority date: 1986-02-13
Filing date: 1986-02-13
Publication date: 1987-08-19
Also published as: GB8603508D0

Abstract

A refrigerating and freezing appliance 1 in which the refrigerating compartment 2 is cooled by air drawn from the freezer compartment 3 via duct (9 Fig. 2), but constrained to encounter the back surface of a heat exchanging plate 13 for frost avoidance, before being fed back to the freezer compartment 3 via duct 10, in the direction of arrow 14. On entry to the freezer compartment the air passes over a cooling evaporator plate 7. <IMAGE>

Description

SPECIFICATION A refrigerating and freezing appliance This invention relates to a combined refrigerator freezer unit, in which there is a freezer compartment operating at temperatures below zero degrees celsius and a refrigerator cooling compartment operating at appreciably higher temperatures, both compartments being served by a single motor-compressor refrigeration system.

Dual-compartment refrigerator/freezers are already well known in the art and are frequently designed with one compartment above the other, each with a forward opening door.

The upper compartment is often the refrigerator cooling compartment with a self defrosting plate and the lower compartment is the freezer, cooled by fixed evaporator plates which also act as shelving. This type of system, in which the freezer operates at considerably lower temperatures than the refrigerator, requires some method of splitting and controlling the refrigerant flow. This gives rise to complications in the refrigerator system.

U.K. Patent Specification 1485666 proposes using the cold air from the freezer compartment to cool and maintain the temperature of the refrigerator. This is done by using a thermostatically regulated electric fan to feed cold conditioned air into the refrigerator compartment from the freezer compartment via a duct linking the two compartments, returning the warmed air to the freezer via a duct in the roof of the freezer compartment. However, one of the drawbacks of this design is that because the circulated air passes into and through this refrigerator compartment, regular defrosting is necessary.Another drawback of this particular design is that as a result of the relative positions of the evaporator and the warm air entry duct in the freezer, there is created a situation whereby the relatively warm air from the refrigerator is passing over frozen food in the freezer compartment before being cooled by the evaporator.

According to the invention there is provided a refrigerating and freezing appliance comprising: a freezing compartment; a refrigerating compartment, including heat-exchanger means having a surface exposed to the interior of said compartment; duct means providing for circulation of air between the two compartments; means, operative in response to an increase in the temperature in said refrigerating compartment above a selected temperature, for encouraging air to flow from the freezing compartment to the refrigerating compartment and back, the arrangement being such that said air communicates with a surface of said heat exchanger other than said exposed surface thereof and does not enter the interior of said refrigerator compartment.

In a preferred embodiment of the invention the duct in the freezing compartment roof, through which the warmed air from the refrigerating compartment is returned, has a cooling evaporator situated immediately beneath it; thus ensuring that the warmed air is cooled again before coming into contact with frozen food. Further evaporators may be added below said first evaporator and can double as shelving for food storage.

In a further preferred embodiment of the invention the heat exchanger means is provided with a means for collecting, draining away and disposing of droplets of condensation from said heat exchanger means.

In another preferred embodiment of the invention the heat exchanger means is located at the top of the refrigerating compartment.

In yet another embodiment of the invention it is preferred that the heat exchanger means be made of aluminium.

It is also preferred that the invention is a dual refrigerator/freezer unit.

It is still further preferred that the invention should be arranged so that the freezing compartment is at the bottom of the unit, with the refrigerating compartment on the top.

In order that the invention may be clearly understood and readily carried into effect specific embodiments of the invention will now be described by way of example with reference to the accompanying drawings of which Figure 1 is a diagrammatic sectional side elevation of a dual compartment refrigerator/ freezer in accordance with one example of the invention.

Figure 2 is a diagrammatic sectional back elevation of the same.

Referring to Figs. 1 and 2. A cabinet 1 encloses two compartments 2 and 3, compartment 2 preferably being a higher temperature refrigerating compartment and compartment 3 being a lower temperature freezing compartment. Between the outer wall 4 of the cabinet and the walls 5 of the compartments 2 and 3 thermal insulating material 6, of the type known in the art is provided. Both compartments 2 and 3 preferably have thermally insulated side hung forward opening doors (not shown).

The freezer compartment 3 is provided with cooling evaporators 7. An associated motor compressor 8, together with a condenser and refrigerant circulating tubes (not shown) forms the refrigerating system for the freezer compartment 3. The freezer compartment 3 is connected to the refrigerating compartment 2 by ducts 9 and 10. Cold air from the freezer compartment 3 is drawn up to the refrigerator compartment 2 via duct 9, in the direction of the arrows 11, by an electric fan 12 situated at the top of the refrigerating compartment 2; then passed across a heat exchanging plate 13, preferably of aluminium and provided with means (not shown) to collect, drain away and dispose of droplets of condensation which may form on said plate 13; thus becoming warmer before being fed back to the freezer compartment 3 via return duct 10, in the direction of arrows 14.

On entering the freezer compartment 3 the warmed air immediately passes over a cooling evaporator plate 7, before coming into contact with any frozen food which may be in said freezer compartment 3.

The temperature of refrigerator compartment 2 is controlled by a thermostat (not shown) which switches circulating fan 12 on an off as requested. The temperature of the freezer compartment 3 is similarly controlled by a thermostat (not shown) that switches the compressor 8 on and off as required.

The electric fan 12 need not be situated at the top of the refrigerating compartment 2.

An alternative embodiment of this invention (not shown) has the fan 12 situated in the centre back of the rerigerating compartment 2, but clearly it could be placed in any convenient position along the flow path.

Thus the dual compartment, single compressor refrigerator/freezer, shown in Figs. 1 and 2, manages to cater for the different requirements of a refrigerator and a freezer by circulating a portion of the freezer air in a closed circuit heat exchanger to provide cooling for the refrigerator; while at the same time, as a consequence of the air circuit being closed, reducing the frequency with which the refrigerator has to be defrosted, compared with existing prior art models.

Claims

1. A refrigerating and freezing appliance comprising: a freezing compartment; a refrigerating compartment; heat exchanger means having a surface exposed to the interior of said refrigerating compartment; duct means providing for circulation of air between the two compartments; means operative in response to an increase in temperature in said refrigerating compartment above a selected temperature, for encouraging air to flow from the freezing compartment to the refrigerating compartment and back, the arrangement being such that said air communicates with a surface of said heat exchanger other than said exposed surface thereof and does not enter the interior of said refrigerator compartment.

2. A refrigerating and freezing appliance according to claim 1, wherein the component of said duct means through which warmed air from the refrigerating compartment is returned to the freezing compartment communicates intimately with a cooling evaporator thus ensuring that the warmed air is cooled again before coming into contact with frozen food.

3. A refrigerating and freezing appliance according to Claim 1 or Claim 2, wherein the heat exchanger means is provided with a means for collecting, draining away and disposing of droplets of condensation from said heat exchanger.

4. A refrigerating and freezing compartment according to any one of Claims 1 to 3, wherein the heat exchanger means is located at the top of the refrigerating compartment.

5. A refrigerating and freezing appliance according to any one of Claims 1 to 4, wherein the heat exchanger means is made of aluminium.

6. A refrigerating and freezing appliance according to Claim 5, wherein the appliance is arranged so that the freezing compartment is disposed beneath the refrigerating compartment.

7. A refrigerating and freezing appliance substantially as herein described with reference to the accompanying drawings.