GB2124351A - Refrigerator - Google Patents

Abstract

A compressor (15) included in a refrigerative cycle of a refrigerator is disposed in a machine compartment defined above a main casing of the refrigerator and the heat radiating means for the refrigerant in the refrigerative cycle includes a drain pan heater (18) disposed in a space below the main casing, a refrigerant condensation tube (16) disposed in the machine compartment, and a condensate-retardation tube (22) arranged along those front wall portions of the main casing which face the doors (9, 10) of the refrigerator. <IMAGE>

Description

SPECIFICATION Refrigerator This invention relates to a refrigerator having a compressor arranged above a main casing of the refrigerator and, in particular, to a refrigerator constituting a unit of a system kitchen and having a refrigerant heat radiating tube arranged to increase the efficiency of the refrigerative cycle.

In a system kitchen, an oven, sink, dishwasher, cupboard, etc. are systematically arranged to fully perform their functions. The refrigerator of this invention is used as one unit of the system kitchen. In a refrigerator of this type it has generally been the case that the machine compartment which includes the compressor for the refrigerative cycle is disposed below the main casing of the refrigerator and that the heat radiation of the refrigerative cycle is performed utilizing the rear plate of the main casing of the refrigerator. In a refrigerator incorporated as one unit of a system kitchen it is desirable from the standpoint of space efficiency, as well as that of heat radiation efficiency, to position the compressor above the main casing of the refrigerator.This arrangement obviates the necessity of providing a heat radiant space at the rear plate of the main casing, as well as a space for the machine compartment which is defined below the main casing of the refrigerator. As a result, it is possible to increase the inner capacity of the freezing compartment and cold storage compartment. In the refrigerator of this type, particular consideration must be paid to the arrangement of the heat radiating tube to radiate heat of the refrigerant for the refrigerative cycle.

It is accordingly the object of this invention to provide a refrigerator having a compressor disposed above the main casing of the refrigerator, in which the heat radiating tube for the refrigerative cycle is arranged to increase the efficiency of the refrigerative cycle.

According to this invention there is provided the refrigerator comprising a compressor which is included in the refrigerative cycle of the refrigerator for circulating a refrigerant through a refrigerant heat radiating means and through at least one refrigerant evaporator disposed in the main casing of the refrigerator, and which is arranged in a machine compartment which is defined above the main casing.The refrigerant heat radiating means includes, at least, a drain pan heater arranged below a drain pan which is located in a space below the main casing, a refrigerant condensation tube disposed in the machine compartment, and a condensateretardation tube disposed along those front wall portions of the main casing which face the refrigerator doors, the refrigerant being circulated from a discharge outlet of the compressor through the drain pan heater, refrigerant condensation tube, condensate-retardation tube and evaporator back to a suction inlet of the compressor.

This invention can be more fully understood from the following detailed description when taken in conjunction with the accompanying drawings, in which: Fig. 1 is a longitudinal, cross-sectional view showing a refrigerator according to one embodiment of this invention; Fig. 2 is a perspective view showing the relative arrangement of parts of a refrigerative cycle in the refrigerator of Fig. 1; and Fig. 3 is a block diagram showing the refrigerative cycle of Fig. 2.

In Figs. 1 and 2, a main casing 2 of a refrigerator 1 includes a rear plate 2a, side plates 2b, top plate 2c and base plate 2d. The main casing 2 includes a freezing compartment 3 at the upper portion and cold storage compartment 4 at the lower portion with a compartment wall 5 between the freezing compartment and the cold storage compartment. An evaporator (first evaporator) 6 for the freezing compartment 3 is disposed along the inner wall of the freezing compartment 3 and an evaporator (second evaporator) 7 for the cold storage compartment 4 is disposed at the upper portion of the cold storage compartment 4.A heat insulating material 8 is filled between the inner wall of the freezing compartment 3 and the rear plate 2a of the main casing 2, the upper wall of the freezing compartment 3 and the top plate 2c, the upper and lower surfaces of the compartment wall 5, the inner wall of the cold storage compartment 4 and the rear plate 2a of the main casing 2, the side walls of the freezing compartment and cold storage compartment and the side plates 2b, and the lower wall of the storage compartment 4 and the base plate 2d. Doors 9 and 10 including an insulating material 8 therein are mounted at the front of the freezing compartment 3 and cold storage compartment, respectively.

Above the top plate 2c of the main casing 2 is located a machine compartment 14 which is enclosed by a cover casing 1 3 with a heat radiant outlet 1 2 of the louver type. A compressor 1 5 and refrigerant condensation tube 1 6 are arranged in the machine compartment. A drain pan 17 is arranged in the space below the base plate 2d of the main casing 2 and a heater for the drain pan is arranged below the drain pan 17.

Fig. 3 shows the refrigerative cycle of the refrigerator as shown in Fig. 1. This invention resides in the order of the arrangement of parts of the refrigerative cycle in the case of the refrigerator of the type as mentioned above.

Explanation will now be given of the arrangement of the above-mentioned parts by referring to Figs. 1, 2 and 3.

A refrigerant is circulated from a smalldiameter discharge outlet 1 5a of the compressor 1 5 to the suction inlet 1 5b thereof through a delivery tube 19, drain pan heater 18, back heat radiating tube 20 in thermal contact with the rear plate 2a, connection tube 21, refrigerant condensation tube 1 6 provided in the machine compartment 14, first condensate-retardation tube 22, second condensate-retardation tube 23, dryer 24, capillary tube 25, second evaporator 7, first evaporator 6 and suction pipe 26. A heat radiating wire 27 is thermally fixed to the serpentine refrigerant condensation tube 1 6 and a dryer 24 is provided to remove the moisture content of the refrigerant. It is possible to omit the back heat radiating tube 20 and second condensate-retardation tube 23.The arrows in Fig. 2 show the directions in which the refrigerant flows.

The operation of the regrigerator 1 as shown in Figs. 1 and 2 will be explained below. The drain pan heater 18, back heat radiant tube 20, refrigerant condensation tube 16, first condensate-retardation tube 22 and second condensate-retardation tube 23 radiate heat, when the refrigerant is passing therethrough, thereby providing a refrigerant condensation means for condensing the refrigerant. A relatively high-temperature and high-pressure gaseous refrigerant from the discharge outlet 1 5a of the compressor 15, while passing through the back heat radiating tube 20 and refrigerant condensation tube 16, radiates heat, and is then gradually liquefied. The refrigerant which has passed through the first condensate-retardation tube 22 and second condensate-retardation tube 23 is almost all liquefied.

Now suppose that in the refrigerant cycle as shown in Fig. 3 the condensation tube 1 6 and first and second condensate-retardation tubes 22 and 23 are arranged in the reverse order, that is, the back heat radiating tube 20, first condensateretardation tube 22, second condensateretardation tube 23 and refrigerant condensation tube 16 are arranged in this order. In this case it is necessary for the liquefied refrigerant from the second condensate-retardation tube 23 to be supplied against gravity to the refrigerant condensation tube 1 6 in the machine compartment 14. Thus, the circulation efficiency of the refrigerant in the refrigerative cycle and the cooling efficiency of the refrigerator as a whole is considerably decreased.

In order to prevent such a decrease in circulation efficiency, it is assumed that the back heat radiating tube 20 and first and second condensate-retardation tubes 22 and 23 are connected in series in this order and that the refrigerant condensation tube 1 6 is connected between the discharge outlet 1 5a of the compressor 1 5 and the delivery tube 19, that is, the discharge outlet 1 5a, refrigerant condensation tube 16, delivery tube 19, drain pan heater 18, back heat radiating tube 20, first condensateretardation tube 22 and second condensateretardation tube 23 are connected in series in this order.Then, since a high temperature is involved in the machine compartment 14, a gaseous refrigerant to be discharged through the discharge outlet 1 5a is only slightly liquefied in the refrigerant condensation tube 1 6 and the slightly liquefied gaseous refrigerant is supplied from the refrigerant condensation tube 1 6 to the delivery tube 1 9. Thus, the circulation efficiency of the refrigerant is also decreased. Even in this case, the liquefaction of the refrigerant progresses in the condensation tube and the condensation tube 1 6 radiates a greater amount of heat, considerably elevating the temperature in the machine compartment 14. Thus, a motor for driving the compressor 1 5 is heated, lowering the efficiency of the refrigerative cycle.Since the gaseous refrigerant from the small-diameter discharge outlet 1 5a of the compressor 1 5 is injected directly into the condensation tube 16, the condensation tube 1 6 is mechanically vibrated due to the pulsating movement of the injected refrigerant.

In the refrigerative cycle of the refrigerator of this invention, however, the refrigerant flows through the drain heater 18, back heat radiating tube 20, refrigerant condensation tube 16, first condensate-retardation tube 22 and second condensate-retardation tube 23 in that order.

Consequently, the refrigerant, i.e., the refrigerant including gaseous refrigerant and liquefied refrigerant flowing through the condensation tube 16, flows smoothly under gravitational force into the first and second condensate-retardation tubes 22 and 23, improving the circulation efficiency of the refrigerant and the over-all refrigeration efficiency. Since the refrigerant liquefied to some extent in the drain pan heater 1 8 and back heat radiating tube 20 is supplied to the condensation tube 16, a relatively small amount of heat is radiated from the condensation tube 1 6.

Therefore, the motor for the compressor is not overheated. Further, the condensation tube 1 6 is not vibrated by the injected refrigerant from a connection tube 21.

According to this invention, therefore, the circulation efficiency of the refrigerant in the refrigerant cycle can be increased, and so, it is possible to provide a refrigerator with excellent cooling efficiency.

Claims (3)

1. A refrigerator comprising a compressor which is included in a refrigerative cycle of said refrigerator for circulating a refrigerant through a refrigerant heat radiating means and through at least one refrigerant evaporator disposed in the main casing of said refrigerator, and which is arranged in a machine compartment which is defined above said main casing, wherein said refrigerant heat radiating means includes, at least, a drain pan heater arranged below a drain pan which is arranged in a space below said main casing; a refrigerant condensation tube disposed in said machine compartment; and a condensate retardation tube disposed along those front wall portions of said main casing which face the doors of said refrigerator; said refrigerant in said refrigerative cycle being circulated from a discharge outlet of said compressor through said drain pan heater, said refrigerant condensation tube, said condensate-retardation tube and said evaporator back to a suction inlet of said compressor.

2. A refrigerator according to claim 1, in which said refrigerative cycle includes a delivery tube, said drain pan heater, a connection tube connected between the outlet of said drain pan heater and the inlet of said refrigerant condensation tube, said condensate-retardation tube, a dryer, a capillary tube, a refrigerant evaporator for a cold storage compartment, a refrigerant evaporator for a freezing compartment, and a suction pipe, all of which are connected in series between the discharge outlet and the suction inlet of said compressor.

3. A refrigerator, substantially as hereinbefore described with reference to the accompanying drawings.