JPH0517580Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a cooling case equipped with a refrigerant circuit that sequentially repeats a simultaneous cooling mode, a one-sided defrosting mode, and a refrigerant recovery mode.

(Prior Art) Conventionally, as this type of cooling case, for example, a refrigerator, the one disclosed in Japanese Patent Application Laid-Open No. 60-29576 is known.

This refrigerator has two evaporators that cool the freezer compartment and an evaporator that cools the refrigerator compartment, and refrigerant from the compressor flows into each evaporator via a condenser and an expansion device. By supplying electricity to each evaporator in the freezer compartment, each evaporator is defrosted.

Considering that the temperature in the freezer and refrigerator compartments increases during this defrosting operation, the freezer and refrigerator compartments are forcibly cooled prior to this defrosting operation, and during the defrosting operation, In order to prevent warm air from entering the freezer, the damper of the evaporator installed in the cold air circulation path of the freezer compartment is closed.

(Problem to be solved by the invention) However, in this cooling case, due to the forced cooling operation performed prior to the defrosting operation, the freezer compartment and refrigerator compartment are temporarily supercooled more than necessary, and the food inside the refrigerator is The problem was that it deteriorated.

In addition, during this defrosting operation, the refrigerant in the evaporator is heated by the defrosting heater and the evaporator temperature may rise more than necessary, which reduces the refrigerating capacity of the compressor during the cooling operation that is performed after the defrosting operation. There was a problem with this.

In view of the above-mentioned conventional problems, the purpose of the present invention is to prevent the deterioration of foods, etc. stored in the case body, and to provide cooling that can obtain the desired refrigerating capacity in the simultaneous refrigerant mode after defrosting operation. The purpose is to provide a case.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention includes first and second evaporators arranged in the cold air circulation path of the case body and through which refrigerant flows vertically, and a compressor. a condenser;
a refrigerant circuit having a first and a second expansion valve; a simultaneous cooling mode in which the refrigerant is sequentially circulated to the evaporator and returned to the compressor to simultaneously cool the first and second evaporators; and a refrigerant discharged from the compressor is transferred to the condenser and the first evaporator. , said second
an expansion valve, a first one-sided defrost mode that circulates to the second evaporator and back to the compressor, defrosting in the first evaporator and cooling in the second evaporator; The refrigerant discharged from the compressor is circulated through the condenser, the second evaporator, the first expansion valve, and the first evaporator and returned to the compressor, and in the second evaporator. A cooling case having a second one-sided defrosting mode for defrosting and cooling in the first evaporator,
It is performed after the first one-sided defrosting mode, and the refrigerant in the first evaporator is transferred to the second expansion valve and the second one side defrosting mode.
a first refrigerant recovery mode in which the refrigerant in the first evaporator is circulated to the evaporator, the compressor, and the condenser and is recovered to the condenser side; and after the second one-sided defrosting mode. The refrigerant in the second evaporator is transferred to the first expansion valve, the first evaporator, the compressor,
a second refrigerant recovery mode in which the refrigerant in the second evaporator is circulated to the condenser and recovered to the condenser side;
installed in the cold air circulation path, regulates circulation of air flowing to the first evaporator when in the first one-sided defrosting mode, and regulates circulation of air flowing to the first evaporator when in the second one-sided defrosting mode. a damper that regulates the circulation of air flowing to the evaporator and releases the regulation of the air circulation to the first and second evaporators when in the simultaneous cooling mode; and a damper that controls the circulation of air to the first and second evaporators when in the simultaneous cooling mode; The refrigerant discharged from the condenser is switched to the lower end side of the first evaporator, and when in the first refrigerant recovery mode, the refrigerant recovered from the first evaporator is switched to the second evaporator side. a first switching valve that switches the refrigerant discharged from the condenser to flow to the lower end side of the second evaporator when in the second one-sided defrosting mode; a second switching valve that switches the recovered refrigerant of the second evaporator to the first evaporator side; and a second switching valve that switches the refrigerant recovered from the second evaporator to the first evaporator side; The flow into the first and second evaporators is regulated through a second expansion valve, and when in the simultaneous cooling mode, this flow restriction is released and the flow into the first and second evaporators is regulated. The refrigerant discharged from the condenser is allowed to flow in through the second expansion valve, and when in the first and second refrigerant recovery modes, this restriction is released and the recovered refrigerant is transferred between the first and second evaporators. a first opening/closing valve for regulating the flow of refrigerant discharged from the condenser when in the simultaneous cooling mode, and regulating the flow of refrigerant discharged from the first and second evaporators when in the first and second refrigerant recovery modes; The flow of the recovered refrigerant is regulated, and when in the first one-sided defrosting mode, this regulation is released and the refrigerant discharged from the upper end side of the first evaporator is passed through the second expansion valve to the second expansion valve. When in the second one-sided defrosting mode, this restriction is released and the refrigerant discharged from the upper end of the second evaporator is allowed to flow through the first expansion valve. a second on-off valve that allows flow to the upper end side of the first evaporator; and a second on-off valve that regulates the flow of refrigerant discharged from the condenser when in the first and second refrigerant recovery modes; It is characterized by having a third on-off valve that allows the refrigerant discharged from the condenser to flow in the one-sided defrosting mode and the simultaneous cooling mode.

(Function) According to the present invention, in the simultaneous cooling mode,
The refrigerant in the compressor is circulated in the following order: condenser → first on-off valve → first and second expansion valves → first and second evaporators → first and second switching valves → compressor.

In the first one-sided defrosting mode, the refrigerant of the compressor is transferred from the condenser to the first switching valve to the first evaporator to the second on-off valve to the second evaporator to the second switching valve to the compressor. and sequentially circulate.

In the second one-sided defrosting mode, the refrigerant of the compressor is transferred from the condenser to the second switching valve to the second evaporator to the first expansion valve to the first evaporator to the first switching valve to the compressor. and sequentially circulate.

In addition, in this one-sided defrosting mode, the evaporator that performs defrosting is closed by a damper and air circulation is restricted, so the flow of heat from the evaporator being defrosted into the case body is restricted. .

When such a defrosting mode, ie, the first one-sided defrosting mode, ends, the first refrigerant recovery mode is performed. In this refrigerant recovery mode, the refrigerant in the defrosted first evaporator passes through the first switching valve → first on-off valve → second expansion valve → second evaporator → second switching valve → compression It flows sequentially from the machine to the condenser and is collected at the condenser side.

When the second one-side defrosting mode is completed, a second refrigerant recovery mode is performed. In this refrigerant recovery mode, the defrosted refrigerant in the second evaporator flows in the order of the second switching valve → the first on-off valve → the first expansion valve → the first evaporator → the first switching valve → the compressor → the condenser, and is recovered on the condenser side.

In such a refrigerant recovery mode, the high temperature refrigerant in the first or second evaporator is recovered to the condenser side, so that the subsequent simultaneous cooling mode described above can be performed efficiently.

(Embodiment) Figures 1 to 5 a, b, and c show an embodiment of the present invention, in which 1 is a compressor, 2 is a condenser, and 3 is a compressor.
a, 3b are first and second evaporators, each of which has refrigerant pipes (not shown) installed in the vertical direction, and 4a, 4b, 4c are normally closed electromagnetic valves (here, the first on-off valve 4b, the second on-off valve 4c, third on-off valve 4a), 5a, 5b are first and second expansion valves, 6a, 6b are check valves, 7
a, 7b are first and second four-way valves (switching valves);
10 is a cooling case body, for example, an open case body (hereinafter referred to as the case body), and an outer box 10
A cold air circulation path 11 is formed between a and the inner box 10b, and a product storage 12 is formed inside the inner box 10b. A partition plate 1 is provided in the cold air circulation path 11.
The evaporators 3a and 3b are arranged through the evaporators 3, and a damper 15 connected to a reversibly driven motor 14 is provided at the upper end of the partition plate 13.
Circulation of the air flowing through the interiors of a and 3b is regulated.

Each of the four-way valves 7a and 7b has its refrigerant flow port A connected to the discharge side of the condenser 2 via the electromagnetic valve 4a, and its refrigerant flow port B connected to the lower end of the refrigerant pipe of the evaporator 3a and 3b. The ports C are respectively connected to the suction side of the compressor 1, and the refrigerant flow port D is closed. Furthermore, when the four-way valves 7a and 7b are turned on, the refrigerant flow port A and the refrigerant flow port D are turned on.
and the refrigerant flow port B and the refrigerant flow port C are communicated with each other, and when turned off, the refrigerant flow port A and the refrigerant flow port B and the refrigerant flow port C and the refrigerant flow port D are communicated with each other. It's summery.

The upper end of the refrigerant pipe of each of the evaporators 3a, 3b is connected to each of the expansion valves 5a, 5b connected in series and each check valve 6a, 6b connected in series. point and the connection midpoint of each of the refrigerant flow ports A via the electromagnetic valve 4b, and the connection midpoint of each of the expansion valves 5a, 5b and each of the check valves 6a,
They are connected to the connection middle points of 6b through the electromagnetic valves 4c. Note that the check valve 6a regulates the flow of refrigerant to the first evaporator 3a side, and the check valve 6b regulates the flow of refrigerant to the second evaporator 3b side. ing.

FIG. 3 shows the electric circuit of the open show case according to this embodiment. 20 is a computer-configured controller with a timer function;
Each of the solenoid valves 4a to 4c, each of the four-way valves 7a,
7b and the motor 14 of the damper 15 are connected, and the solenoid valves 4a to 4c and the four-way valves 7a and 7b are connected to each other.
And the motor 14 is driven and controlled as shown in the time chart of FIG.

That is, the solenoid valves 4a, 4b and the four-way valve 7
a, 7b are turned on, the motor 14 is driven, and the damper 15 is positioned between the evaporators 3a, 3b, the refrigerant of the compressor 1 {solid line arrow in FIG. 5a} is condensed. 2, each solenoid valve 4
a, 4b and the expansion valves 5a, 5b into the upper ends of the refrigerant pipes of the evaporators 3a, 3b. The incoming refrigerant flows back to the compressor 1 via the four-way valves 7a and 7b. As a result, a simultaneous cooling mode is formed, and the evaporators 3a and 3b generate heat absorption, thereby cooling the air in the cold air circulation path 11 and feeding it into the product storage 12.

After the operation in the simultaneous cooling mode continues for a predetermined period of time, the solenoid valve 4c is turned on, the solenoid valve 4b and the four-way valve 7a are turned off, and the motor 14 is driven and the damper is turned on. 15 to close the first evaporator 3a side.
At this time, the refrigerant of the compressor 1 {solid line arrow in FIG. do. The inflow refrigerant flows through the check valve 6
a, the inflow refrigerant flows into the upper end of the refrigerant pipe of the second evaporator 3b via the electromagnetic valve 4c and the second expansion valve 5b, and further, the inflow refrigerant flows into the compressor 1 via the four-way valve 7b. Reflux to. As a result, the first one-sided defrosting mode is formed, an endothermic action occurs in the second evaporator 3b, and the air cooled by the second evaporator 3b is passed through the cold air circulation path 11 to the second evaporator 3b. The products are fed to the product storage 12. On the other hand, in the first evaporator 3a, defrosting is performed from the lower side of the first evaporator 3a, thereby warming the surrounding air at the lower side. The heated air gradually rises and the first
It also flows to the upper side of the first evaporator 3a, and defrosts the entire first evaporator 3a in a short time.

In this way, the first evaporator 3a on the side to be defrosted
is closed by the damper 15, the inflow of air to the evaporator 3a side is regulated, and the product storage 1
2. Heat generated during defrosting does not leak into the interior.

Further, since the defrosting air is cooled as it rises to the upper side of the evaporator 3a, the damper 15
Even if the defrosting air leaks into the cold air circulation path 11 due to insufficient airtightness or insulation, the temperature within the product storage 12 will not be significantly affected.

Further, after the operation in the first one-sided defrosting mode continues for a predetermined period of time, the solenoid valve 4b is turned on, and the solenoid valves 4a and 4c are turned off. At this time, the refrigerant in the first evaporator 3a {solid line arrow in FIG. Further, the inflowing refrigerant passes through the four-way valve 7b, the compressor 1, and the condenser 2, and stays on the solenoid valve 4a side. As a result, the second evaporator 3b continues to absorb heat, and the refrigerant on the first evaporator 3a side is recovered. In this way, since the refrigerant in the first evaporator 3a, which has been defrosted after the one-sided defrosting mode is completed, is recovered to the condenser 2 side, the subsequent simultaneous cooling mode operation can be performed efficiently. be exposed.

Furthermore, after continuing the operation in the first refrigerant recovery mode for a predetermined time, the solenoid valve 4a and the four-way valve 7a are turned on to form the simultaneous cooling mode.

Furthermore, the damper 1 is operated in the simultaneous cooling mode until a predetermined time period elapses, that is, the time period during which the temperature of the evaporator 3a on the refrigerant recovery side decreases to about 0°C.
5 on the evaporator _3a side, and the evaporator 3a
The side refrigerant circulation path 11 is closed. As a result, circulating air does not sufficiently flow through the evaporator 3a, which has become hot due to the defrosting and recovery, and no load is applied to the compressor 1 as in the conventional case. Further, the surrounding air heated by the evaporator 3a is also regulated by the damper 15, and the product storage 12
There is no possibility that the temperature inside the refrigerator will increase. When the time period has elapsed, the damper 15 is driven by the motor 14.
is located between the evaporators 3a and 3b, and the cooling air from the evaporators 3a and 3b is fed into the product storage 12.

Furthermore, after the simultaneous cooling mode continues for a predetermined time, the solenoid valve 4c is turned on, and
The electromagnetic valve 4b and the four-way valve 7b are turned off, the motor 14 is driven, and the damper 15 closes the second evaporator 3b.
At this time, the refrigerant of the compressor 1 {dotted chain arrow in FIG. Inflow. The inflow refrigerant flows through the check valve 6b, the electromagnetic valve 4c, and the first expansion valve 5a.
The refrigerant flows into the upper end of the refrigerant pipe of the first evaporator 3a through the four-way valve 7a, and the refrigerant flows back into the compressor 1 through the four-way valve 7a. As a result, a second one-sided defrosting mode is formed, and the first evaporator 3a
In the second evaporator 3b, an endothermic action is produced, and in the second evaporator 3b, a defrosting action is produced. This defrosting action also operates in the same manner as the first one-sided defrosting mode described above,
The defrosting time is shortened and the effect on the internal temperature is small.

Furthermore, after the second one-sided defrosting mode is finished, the solenoid valve 4b is turned on, and the solenoid valves 4a and 4c are turned off. At this time, the refrigerant in the second evaporator 3b {dotted chain arrow in FIG. 3
Further, the inflowing refrigerant flows into the four-way valve 7
a. Remains on the electromagnetic valve 4a side via the compressor 1 and the condenser 2. This forms the second refrigerant recovery mode.

In this way, by sequentially repeating the simultaneous cooling mode, the first one-sided defrosting mode, the first refrigerant recovery mode, the simultaneous cooling mode, the second one-sided defrosting mode, and the second refrigerant recovery mode, the case body 1
Refrigeration operation of the product storage 12 of No. 0 is performed.

(Effect of the invention) As explained above, according to the invention, since the inside of the case body is cooled at the same time during the defrosting operation, the forced cooling operation performed prior to the defrosting operation as in the conventional case The products etc. housed in the case body will not deteriorate.

Further, since the refrigerant in the defrosting evaporator is recovered to the condenser side in the refrigerant recovery mode that is performed after the single-sided defrosting mode, the simultaneous cooling mode that is performed after the refrigerant recovery mode is efficiently performed.

[Brief explanation of the drawing]

Figures 1 to 5 a, b, and c show one embodiment of the present invention, in which Figure 1 is a sectional view showing an open shower case, Figure 2 is a refrigerant circuit diagram of the open shower case, and Figure 3 is a refrigerant circuit diagram of the open shower case. The figure shows the electric circuit diagram of the open case. Figure 4 is a time chart showing controller control. Figure 5 a is a refrigerant circuit diagram showing simultaneous cooling mode. Figure 5 b is a refrigerant circuit diagram showing one-sided defrosting mode. , FIG. 5c is a refrigerant circuit diagram showing the refrigerant recovery mode. In the figure, 1...compressor, 2...condenser, 3a...
First evaporator, 3b... Second evaporator, 4a...
Third on-off valve, 4b...First on-off valve, 4c...
Second on-off valve, 5a...First expansion valve, 5b...
Second expansion valve, 7a...First switching valve, 7b...
...Second switching valve, 10...Case body, 11...
...Cold air circulation path, 15...Damper.

Claims (1)

[Claims for Utility Model Registration] First and second evaporators 3a disposed in the cold air circulation path 11 of the case body 10 and through which refrigerant flows upward and downward;
3b, compressor 1, condenser 2, first and second
The refrigerant circuit has expansion valves 5a and 5b, and the refrigerant circuit transfers the refrigerant discharged from the compressor 1 to the condenser 2, the first and second expansion valves 5a and 5b, and the first and second expansion valves 5a and 5b. It is sequentially circulated to the second evaporators 3a, 3b and returned to the compressor 1, and the first and second evaporators 3
a and 3b simultaneously;
b, a first one-sided defrosting mode in which the circuit is circulated to the second evaporator 3b and returned to the compressor 1, the first evaporator 3a is defrosted, and the second evaporator 3b is cooled; and the refrigerant discharged from the compressor 1 is passed through the condenser 2, the second evaporator 3b, and the first expansion valve 5.
a, a second one-sided defrosting mode in which the circuit is circulated to the first evaporator 3a and returned to the compressor 1, defrosted in the second evaporator 3b, and cooled in the first evaporator 3a; In the cooling case, the cooling case is carried out after the first one-sided defrosting mode, and the refrigerant in the first evaporator 3a is transferred to the second expansion valve 5.
b. a first refrigerant recovery mode in which the refrigerant in the first evaporator 3a is circulated to the second evaporator 3b, the compressor 1, and the condenser 2 and is recovered to the condenser 2 side; This is performed after the second one-sided defrosting mode, and the refrigerant in the second evaporator 3b is transferred to the first expansion valve 5.
a, a second refrigerant recovery mode in which the refrigerant in the second evaporator 3b is circulated to the first evaporator 3a, the compressor 1, and the condenser 2 and is recovered to the condenser 2 side; installed in the cold air circulation path 11, regulates the circulation of air flowing to the first evaporator 3a when in the first one-sided defrosting mode, and regulates the circulation of air flowing to the first evaporator 3a when in the second one-sided defrosting mode. a damper 15 that regulates the circulation of air flowing to the first and second evaporators 3b, and releases the regulation of the air circulation to the first and second evaporators 3a and 3b when in the simultaneous cooling mode; When in one side defrosting mode, the condenser 2
The refrigerant discharged from the first evaporator 3a is switched to flow to the lower end side of the first evaporator 3a, and when in the first refrigerant recovery mode, the refrigerant recovered from the first evaporator 3a is switched to flow to the lower end side of the second evaporator 3b. First switching valve 7a to flow
and, when in the second one-sided defrosting mode, the condenser 2
The refrigerant discharged from the second evaporator is switched to flow toward the lower end of the second evaporator 3b, and when in the second refrigerant recovery mode, the refrigerant recovered from the second evaporator is switched to flow toward the first evaporator 3a. a second switching valve 7b; and when in the first and second one-sided defrosting modes, the refrigerant discharged from the condenser 2 passes through the first and second expansion valves 5a and 5b. evaporator 3
a, 3b, and when in the simultaneous cooling mode, this inflow restriction is released and the first and second
The first and second expansion valves 5 to the evaporators 3a, 3b of
The refrigerant discharged from the condenser 2 is allowed to flow in through the condenser 3a and 5b, and when in the first and second refrigerant recovery modes, this restriction is released and the refrigerant is transferred to the first and second evaporators 3a, 5b.
The first on-off valve 4b allows the recovered refrigerant to flow between the valves 3b and 3b.
and regulating the flow of the refrigerant discharged from the condenser 2 in the simultaneous cooling mode, and regulating the flow of the refrigerant discharged from the condenser 2 in the first and second refrigerant recovery modes, and controlling the flow of the refrigerant in the first and second evaporators 3a,
The flow of the recovered refrigerant from the first evaporator 3b is regulated, and when in the first one-sided defrosting mode, this regulation is released and the refrigerant discharged from the upper end side of the first evaporator 3a is transferred to the second expansion valve 5b. via the second evaporator 3b
When in the second one-sided defrosting mode, this restriction is released and the refrigerant discharged from the upper end of the second evaporator 3b is passed through the first expansion valve 5a to the first expansion valve 5a. a second on-off valve 4c that allows the refrigerant to flow to the upper end side of the evaporator 3a; When in one-sided defrosting mode and simultaneous cooling mode, the third
A cooling case characterized in that it has an on-off valve 4a.