JPH05223368A - Refrigerator - Google Patents

Abstract

PURPOSE: To improve the efficiency of a refrigeration system while energy saving is realized by connecting evaporators for fresh food compartment and freezer compartment to each other in a parallel refrigerant flow relationship between a condenser and a compressor, and making a refrigerant flow to the compressor through either one of the evarporators regardless of the other evaporator. CONSTITUTION: In a refrigerator 10, a freezer compartment 13 and a fresh food compartment 14 are demarcated by insulating external walls 11 and an insulating partition wall 12 and doors 15 and 16 are respectively attached to the entrances of the compartments 13 and 14. A refrigerating system is constituted of an evaporator for freezer 20, an evaporator 21 for fresh food compartment, a condenser 22, and a compressor 23. The evaporators 21 and 20 are connected in a parallel refrigerant flow relationship between the condenser 22 and compressor 23. In addition, a refrigerant is made to flow to the compressor 22 from the condenser 22 through either one of the evaporators 20 and 21 regardless of the other evaporator. Therefore, the efficiency of the refrigerating system can be improved while energy saving is realized and, accordingly, the occurrence of such a failure that the foodstuffs in the freezer compartment are insufficiently cooled can be eliminated.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates generally to refrigeration systems, and more particularly to a home refrigerator / freezer having a plurality of evaporators connected in parallel to a refrigerant flow circuit.

[0002]

[Related Application] This application is Heinz assigned to the applicant.
Heinz Jaster US Patent No. 49109
Nos. 72 and 4918942, and James Day US patent application Ser. No. 07/612290 (filed Nov. 9, 1990) assigned to the present applicant.

[0003]

2. Description of the Related Art The refrigeration system used in today's typical domestic refrigerator-freezer is a continuous refrigeration system that uses a closed circuit that includes a compressor, a condenser, an expansion device (usually a capillary tube), and an evaporator. And circulate it back to the compressor. The refrigerant is a two-phase substance having a liquid phase and a vapor phase.
The refrigeration system repeats the refrigerant from liquid to vapor, and
It acts to transform it into a liquid, thus transporting energy from inside the refrigerator by extracting heat from the freezer compartment and expelling it from the outside air outside the refrigerator. In a typical refrigerator, an evaporator is installed in a freezer, air is blown to the evaporator by a fan, the resulting air flow is divided, most of the air flow is circulated in the freezer, and part of the air flow is And circulate it in the fresh food room. In this way, the freezer is typically maintained between -10 ° F and + 15 ° F, while the fresh food compartment is maintained at + 33 ° F to + 47 ° C.
Hold between ° F. Such refrigerators do not operate at the highest efficiency possible. This is because the refrigerating action of the refrigerating cycle, which is appropriate for the freezer, is lower than the temperature required to maintain the fresh food compartment at an appropriate temperature. Since the mechanical energy required to cool to a relatively low temperature is greater than the energy required to cool to a relatively high temperature, a typical simple vapor compression cycle consumes 2 mechanical energy. More than the mechanical energy of the cycle with cooling at one temperature level.

US Pat. Nos. 4,910,972 and 49
In the refrigeration system disclosed in No. 18942,
A separate evaporator is used to obtain the freezing function of the freezer room and the fresh food room. In these patents,
Compressors or compression means in the form of two-stage compressors or double compressors have been used. Refrigerant from the freezer evaporator is supplied to the low pressure stage, which raises its pressure to an intermediate level. The vapor stage refrigerant from the fresh food compartment is combined with the refrigerant exiting the low pressure compression stage, and all recirculating refrigerant is fed to the high pressure compression stage where the refrigerant pressure is at the desired relatively high compressor outlet pressure. Raise to.

Pending US Patent Application (Applicant's Ref. Number R
D-19924) also discloses a refrigeration circuit using separate evaporators for the freezer compartment and the fresh food compartment. The compression means used in this circuit is a combination of a single stage compressor and a valve that selectively connects the outlet of the freezer evaporator and the vapor stage refrigerant from the fresh food compartment to the single stage compressor. .. Thus, as the valve feeds refrigerant from the freezer evaporator to the compressor, the compressor boosts the refrigerant pressure from the low pressure of the freezer evaporator to the desired high compressor outlet pressure at once. On the other hand, when the valve supplies vapor refrigerant from the fresh food compartment evaporator to the compressor, the compressor only needs to increase the pressure from the intermediate pressure level to the desired compressor outlet pressure.

In all of the aforementioned related US patents and applications, a fresh food compartment evaporator and a freezer evaporator are connected in series with a refrigerant flow circuit, with a phase separator connected therebetween. The phase separator serves to separate the vapor stage refrigerant and the liquid stage refrigerant, sending the liquid refrigerant to the freezer evaporator and the vapor refrigerant to the compressor means. In any of these refrigerant circuits, it is possible that the fresh food compartment evaporator will evaporate at least a majority of the refrigerant when the fresh food compartment requires substantial cooling. Therefore, the phase separator will not have enough liquid refrigerant available to supply the freezer evaporator with an adequate amount, resulting in a “depleted” freezer evaporator and insufficient freezer cooling. become.

[0007]

OBJECTS OF THE INVENTION It is an object of the present invention to provide an improved refrigerator including a refrigerant system. Another object of the present invention is to provide a household refrigerator in which separate evaporators are used for the fresh food compartment and the freezer compartment, and the refrigerant flow through each evaporator is independent of the refrigerant flow through the other evaporator. To provide.

Another object of the present invention is to provide a household refrigerator in which a plurality of evaporators are connected to a single refrigerant circuit in parallel refrigerant flow relationship.

[0009]

SUMMARY OF THE INVENTION A domestic refrigerator of the present invention comprises a compressor means, a condenser means connected to receive refrigerant discharged from the compressor means, a fresh food compartment and a fresh food compartment for cooling the fresh food compartment. The food room evaporator, the freezer room, and the freezer evaporator which cools a freezer room are provided. The fresh food compartment evaporator and the freezer evaporator are connected in parallel refrigerant flow relationship between the condenser means and the compressor means so that the refrigerant emerging from the condenser means is either of the evaporators. Through, to the compressor means regardless of the flow of refrigerant flowing to the other evaporator.

The gist of the invention is as set forth in the claims. The present invention will be described in detail below with reference to the drawings so that the configuration and the method for carrying out the present invention, together with other objects and effects of the present invention, can be better understood.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring initially to FIG. 1, a domestic refrigerator-freezer 10 is shown in a simplified diagram. This refrigerator 10 includes an insulating outer wall 11 and an insulating partition wall 12.
The partition wall 12 divides the refrigerator into a freezer (freezing) chamber 13 and a fresh food chamber 14. Door 15
And 16 are a freezer room 13 and a fresh food room 1, respectively.
It becomes the entrance to the inside of 4. Below the fresh food compartment 14 is a machine or equipment compartment 17 in which the various operating elements of the refrigerator are housed.

[0012] Typically, current home refrigerator refrigeration systems maintain the freezer compartment in the temperature range of -10 ° F to + 15 ° F, while the fresh food compartment is about + 33 ° F to +4.
Operate to maintain a temperature range of 7 ° F. Refrigerator 1
The refrigeration system for 0 comprises a first or freezer evaporator (evaporator) 20, a second or fresh food compartment evaporator 21, a condenser (condenser) 22, and a compressor or compressor means 23. These basic units are interconnected by tubing in a fluid and vapor tight refrigerant circuit to circulate a two phase refrigerant, as is well known in the art. Specifically, the compressor 23 is the first
Alternatively, it is a two-stage type having a low pressure compression stage and an upper or high pressure compression stage. High-pressure refrigerant gas or vapor is compressed by the compressor 2
3 exits 24 and flows to the condenser 22, where it is converted from a gas to a liquid. Liquid refrigerant flows from the condenser 22 through the dryer 25 to a valve or joint 26, which splits the refrigerant flow into two parallel refrigerant passages. The first passage extends through the expansion device 27 to the produced food compartment evaporator 21 and then back to the intermediate pressure inlet 28 of the compressor. The other refrigerant flow path from the joint 26 extends through the expansion device 29 to the freezer evaporator 20,
It then returns to the low pressure inlet 30 of the compressor.

The inflation means or devices 27 and 29 can be of any of a number of well known constructions. In a typical household refrigerator, this expansion device takes the form of a capillary tube (capillary tube), and as the refrigerant passes through the capillary, the refrigerant expands and begins to change from liquid to vapor. Other types of refrigeration systems use preset or regulated expansion valves that allow the refrigerant to expand. Such valves can also be used in home refrigerators. However, the low cost of capillaries is suitable for this type of application.

In a refrigerator having a separate freezer evaporator and fresh food compartment evaporator, freezer evaporator 20 operates at a significantly lower temperature than fresh food compartment evaporator 21. Therefore, the pressure of the vapor or gas refrigerant flowing from the evaporator 20 to the compressor 23 is significantly lower than that of the refrigerant flowing from the evaporator 21 to the compressor 23. The refrigerant from the freezer evaporator 20 is sent to the low pressure inlet 30 of the two-stage compressor 23 and is compressed by its first or low pressure stage to an intermediate pressure which roughly corresponds to the outlet pressure of the fresh food compartment evaporator 21. Fresh food room evaporator 21
The refrigerant coming out of is sent to the intermediate pressure inlet 28 of the compressor 23. Refrigerant from the low pressure stages of fresh food compartment evaporator 21 and compressor 23 is compressed by the second stage to a relatively high outlet pressure of compressor 23. In this way, energy can be saved as in the related prior art described above. It circulates only the refrigerant needed to cool the freezer, between the low level of freezer evaporator outlet pressure and the high level of compressor outlet pressure, and the refrigerant needed to cool the fresh food compartment, This is because there is circulation between the intermediate pressure level required to provide the desired fresh food compartment operating temperature and the high compressor outlet pressure level.

In contrast to the prior art described above, the refrigerant flowing to the freezer evaporator 20 does not flow to the fresh food compartment evaporator 21. Therefore, the fresh food room evaporator 21 does not take the refrigerant from the freezer evaporator 20, and the freezer evaporator 20 is guaranteed to have sufficient refrigerant for proper operation. The portion of the pipe 31 connecting the outlet of the fresh food compartment evaporator 21 to the compressor 23 and the portion of the pipe 32 connecting the valve or joint 26 to the expansion means 29 are, as indicated at 33, mutually They are arranged in a heat transfer relationship. Such an arrangement is usually 2
This is accomplished by brazing the book tubing in a reverse flow relationship or by wrapping one tubing exactly around the other. As a result of this heat transfer relationship, the relatively low temperature refrigerant flowing from the fresh food compartment evaporator 21 pre-cools and intermediate cools the relatively high temperature refrigerant flowing to the freezer evaporator 20. This intercooling further improves the efficiency of the system.

A thermostat 35 is installed in the fresh food compartment 14 and senses the ambient temperature inside the compartment. The thermostat 35 has a predetermined high temperature, usually the fresh food compartment 14
When a temperature close to the upper temperature limit of, for example, + 47 ° F is sensed, a thermostat operates to connect the compressor 23 to a power source, for example, a household electric system, and thus, the compressor 23 has a thermostat 35 at a predetermined low temperature, usually, The operation continues until a temperature near the lower limit of the operating range of the fresh food compartment 14 is detected, for example, + 33 ° F. However, other more complex control systems may be used. For example, an additional thermostat can be installed in the freezer compartment 13 and both thermostats in the freezer and the fresh food compartment work in concert with the compressor 23,
Therefore, the operation of the refrigeration system is controlled. It should be noted that for the sake of brevity, various other components normally included in home refrigerators, such as lights and fans for air circulation, have been omitted.

Needless to say, the portion where the refrigerant pipe and the wiring pass through the insulating wall 11 is sealed to prevent air leakage. That is, the openings 37 and 38 are only present for convenience of illustration. FIG. 2 shows another refrigerant circuit which is substantially similar to that shown in FIG. 1 except for the compression means. The same components are designated by the same reference numerals. The compression means 40 comprises a first low pressure compressor 41 having an inlet 42 and an outlet 43, and an inlet 45.
And a second high pressure compressor 44 having an outlet 46. The compressors 41 and 44 are independent of each other, and each compressor is operated by its own motor, but both compressors are controlled to operate simultaneously. Alternatively, both compressors always operate simultaneously, so both may be operated by a single motor. The refrigerant discharged from the freezer evaporator 20 is supplied to the inlet 42 of the low-pressure compressor 41, and the compressor 41 compresses the refrigerant to an intermediate pressure corresponding to the outlet pressure of the fresh food compartment evaporator 21. Low-pressure compressor 41 and fresh food room evaporator 2
To supply the refrigerant from both of 1 to the inlet of the high pressure compressor 44,
The combined refrigerant is compressed to a high pressure by the compressor 44. This high pressure refrigerant flow from the outlet 46 of the compressor 44 is transferred to the condenser 2
Supply to 2.

FIG. 3 illustrates another refrigerant circuit substantially similar to that shown in FIGS. 1 and 2, except that a compression means is used that includes a valve and a single compressor. The same components are designated by the same reference numerals. A pair of inlets 51 and 52 and an outlet 5
3 is connected between the outlets of the evaporators 20 and 21 and the inlet of the single-stage compressor 54. The valve 50 serves to alternately connect either of the evaporators 20 and 21 to the inlet of the single stage compressor 54, so that as long as the compressor 54 is operating, the valve 50 will direct the refrigerant to the evaporator 20 and. Alternately from each of 21 to compressor 54. When the compressor 54 is connected to the evaporator 20, the compressor 54 compresses refrigerant from a relatively low outlet pressure of the evaporator 20 to a high compressor outlet pressure. On the other hand, when the compressor 54 is connected to the evaporator 21, the compressor 54 compresses the refrigerant from the intermediate pressure to the same compressor outlet pressure. For more information on the construction, operation and control of valves suitable for use in this circuit,
Shown and described in pending US patent application Ser. No. 07 / 612,290. A two-stage compressor 23 as shown in FIG. 1 and two separate compressors 4 as shown in FIGS. 2 and 4.
Compression means, such as 40, including 1 and 44, and compression means, including the arrangement of valve 50 and compressor 54 as shown in FIG. 3, are essentially compatible in various embodiments of the invention. Can be used with sex.

FIG. 4 is substantially the same as that shown in FIGS. 1 and 2, except that the freezer pipe and the fresh food compartment pipe are arranged in a heat exchange relationship to intercool the refrigerant flowing to the freezer evaporator. 2 shows another refrigerant circuit of FIG. The same components are designated by the same reference numerals. In FIG. 4, a pipe section 56 connected between the expander 27 and the inlet of the fresh food compartment evaporator 21 is connected to a pipe section 32 connecting the valve 26 to the expander 28 for the freezer evaporator 20. , 57 are arranged in a heat exchange relationship. In addition to this, the pipe portion 58 connecting the outlet of the freezer evaporator 20 to the compression means 40 is also arranged in heat exchange relation with the pipe portions 32 and 59. This double heat exchange relationship allows the cooling capacity of the refrigerant in the system to be more fully utilized,
Therefore, efficiency is increased.

In the above-mentioned embodiment, the pipe parts for carrying the refrigerant to the two evaporators are arranged in a heat transfer relationship with each other,
Intermediate cooling of the refrigerant flowing to the freezer evaporator is performed.
In the embodiment shown in FIG. 5, this freezer evaporator refrigerant intercooling is performed in a slightly more indirect manner. For this purpose, an intercooler or heat transfer device 62 is connected in a refrigerant flow relationship between the joint or valve 26 and the freezer refrigerant expansion means 28, into the fresh food compartment 14, preferably the fresh food compartment evaporation. It is located near the container 21. With this arrangement, the refrigerant passing through the intercooler 62 is cooled by the air in the fresh food compartment 14, that is, by the action of the fresh food compartment evaporator 21. Intercooler 62
Is conveniently configured as a small heat exchanger such as an evaporator or condenser. The other features of this refrigerator are shown in Fig. 1.
Substantially the same as the embodiment shown in FIG.

[Brief description of drawings]

1 is a simplified diagrammatic side view of a household refrigerator incorporating one embodiment of the present invention. FIG.

FIG. 2 is a schematic circuit diagram of another refrigerant circuit to which the present invention is applied, which is suitable for a household refrigerator.

FIG. 3 is a schematic circuit diagram of another refrigerant circuit to which an embodiment of the present invention suitable for a domestic refrigerator is applied.

FIG. 4 is a schematic circuit diagram of still another refrigerant circuit to which an embodiment of the present invention suitable for a household refrigerator is applied.

FIG. 5 is a simplified diagrammatic side view of a domestic refrigerator including a refrigerant circuit incorporating another embodiment of the present invention.

[Explanation of symbols]

 10 Refrigerator 13 Freezer Room 14 Fresh Food Room 20 Freezer Evaporator 21 Fresh Food Room Evaporator 22 Condenser 23 Compressor 24 Compressor Outlet 25 Dryer 26 Valve 27, 29 Expander 28 Intermediate Pressure Inlet 30 Low Pressure Inlet 31, 32 Piping 35 Thermostat 40 Compressing means 41 First low pressure compressor 44 Second high pressure compressor 50 Flow control valve 54 Single stage compressor 62 Intercooler

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Dwight William Jacobs, Louisville, Kentucky, USA, Hawthorn Ave, 2230 (72) Inventor Willard Eugene Payton, Kentucky, Louisville, Marvin・ Avenue, 3712

Claims (9)

[Claims] 1. A compressor means, a condenser means connected to receive the refrigerant discharged from the compressor means, a fresh food compartment, and a fresh food compartment evaporator for cooling the fresh food compartment. A freezer compartment and a freezer evaporator for cooling the freezer compartment, wherein the fresh food compartment evaporator and the freezer evaporator are in parallel refrigerant flow relationship between the condenser means and the compressor means. A refrigerator connected to which refrigerant flows from the condenser means through one of the evaporators to the compressor means independently of the other of the evaporators. 2. A pre-cooling means for extracting heat from the refrigerant flowing from the condenser means to the freezer evaporator by utilizing the cooling effect of the refrigerant flowing through the fresh food compartment evaporator. The refrigerator according to 1. 3. Further comprising piping means for establishing a fluid flow relationship between said compressor means, said condenser means, said fresh food compartment evaporator and said freezer evaporator, respectively. The refrigerator according to claim 1, wherein a portion that establishes a refrigerant flow to the fresh food compartment evaporator and a portion of the piping means that establishes a refrigerant flow to the freezer evaporator are arranged in a heat transfer relationship. 4. Fresh food compartment refrigerant expansion means connected in refrigerant flow relationship between said condenser means and said fresh food compartment evaporator, and between said condenser means and said freezer evaporator. A freezer refrigerant expansion means connected in a refrigerant flow relationship with, the portion of the piping means for the fresh food room evaporator located downstream from the fresh food room refrigerant expansion means, the freezer evaporation The refrigerator according to claim 3, wherein the refrigerator is disposed in a heat transfer relationship with a portion of the piping means for a container located upstream of the freezer refrigerant expansion means. 5. The portion of the piping means connected between the fresh food compartment refrigerant expansion means and the fresh food compartment evaporator is connected between the condenser means and the freezer refrigerant expansion means. 5. The refrigerator according to claim 4, wherein the refrigerator is arranged in a heat transfer relationship with a portion of the piping means. 6. The portion of the piping means connected between the fresh food compartment evaporator and the compressor means is connected between the condenser means and the freezer refrigerant expansion means. The refrigerator according to claim 4, which is arranged in a heat transfer relationship with a portion of the piping means. 7. The pre-cooling means is connected in a refrigerant flow relationship between the condenser means and the freezer evaporator and is arranged in the fresh food compartment to remove the refrigerant flowing to the super-cooling means. The refrigerator according to claim 2, further comprising subcooling means for extracting energy. 8. The compressor means includes a low compression stage and a high compression stage, the freezer evaporator is connected to supply refrigerant to the low compression stage, and the fresh food compartment evaporator is The refrigerator according to claim 1, which is connected to supply a refrigerant to the high compression stage. 9. Further, a refrigerant flow relationship is connected between each of the evaporators and the compressor means, and one of the evaporators is brought into a refrigerant flow relationship with the compressor means at any specific time. 2. The refrigerator according to claim 1, further comprising a refrigerant flow control means having a function of selectively connecting.