JPH05308943A - Freezing equipment - Google Patents

Abstract

PURPOSE:To obtain a freezing equipment capable of improving drying ability and simultaneously carrying out good drying operation without increasing a charge amount of refrigeration medium. CONSTITUTION:In the objective freezing equipment connecting a compressor 1, a condenser 2, a receiver 3, an expanding valve 4 and an evaporator 5 through piping and simultaneously providing a reheater 6 side by side to the evaporator 5 and allowing the refrigeration medium to flow to both of the reheater 6 and evaporator 5 so as to dry the interior of a chamber, a three-way valve 7 is provided in a discharge piping of the compressor 1 and the three-way valve 7 is changed over in drying operation and a refrigeration medium discharged from the compressor 1 is made to flow in the order of the reheater 6, receiver 3 and evaporator 5 thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerating apparatus used to dry fish, noodles, agricultural products and the like stored in a drying cabinet at a suitable temperature with cold air.

[0002]

2. Description of the Related Art Conventionally, a refrigerating apparatus of this type has been disclosed in Japanese Patent Laid-Open No.
Various refrigeration circuits have been devised as shown in Japanese Patent No. 43270.

For example, as shown in FIG. 8, a compressor 50, a condenser 51, a liquid receiver 52, an expansion valve 53, and an evaporator 54 are connected by pipes, and a reheater 55 is installed in parallel with the evaporator 54.
And a branch pipe 56 branched from the outlet of the condenser 51 and connected to the reheater 55. Further, electromagnetic valves 57, 58 and 59 are provided on the branch pipe 56, the inlet side of the liquid receiver 52 and the inlet side of the expansion valve 53. In FIG. 8, the inside of the broken line indicates the inside of the outdoor unit, the inside of the chain double-dashed line indicates the inside of the drying cabinet, 60 and 61 are check valves, 62 is a temperature sensor, 63 is a humidity sensor, and 64 is the temperature and humidity inside the cabinet. 2 shows a control device for controlling.

In the cooling operation, the refrigerant is flowed in the order of the compressor 50, the condenser 51, the liquid receiver 52, the expansion valve 53, and the evaporator 54 to cool the inside of the drying chamber.

During the drying operation, the refrigerant discharged from the condenser 51 is introduced into the reheater 55 through the branch pipe 56, and then the liquid receiver 52 and the evaporator 54 are flowed in this order to the reheater 55. And the evaporator 54 are made to flow while the refrigerant is flowing to dry the inside of the refrigerator.

[0006]

However, according to the above construction, during the drying operation, the refrigerant discharged from the condenser 51 flows into the reheater 55, so that the temperature of the refrigerant flowing into the reheater 55 is increased. There was a problem that the drying capacity of the reheater 55 was low, which was low.

Further, since there is no refrigerant recovery system during the dry operation, the refrigerant in the outlet side pipe of the condenser 51 remains as it is during the cooling operation, and a large amount of refrigerant charge is required, resulting in a large capacity. The refrigeration system has a problem of being uneconomical.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a refrigerating apparatus which can improve the drying capacity and can perform a good drying operation without increasing the refrigerant charge amount.

[0009]

According to the present invention, a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and
In the refrigerating apparatus in which a reheater is provided in parallel with the evaporator and the inside of the refrigerator is dried by flowing the refrigerant to both the reheater and the evaporator during the drying operation, in the discharge pipe of the compressor. A three-way valve is provided, and during the drying operation, the three-way valve is switched to allow the refrigerant discharged from the compressor to flow in the order of the reheater, the liquid receiver, and the evaporator.

Further, a compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and a reheater is provided in parallel with the evaporator, and during the drying operation, the reheater and the evaporator. In a refrigerating device in which a refrigerant is allowed to flow in both sides to dry the inside of the refrigerator, a three-way valve is provided in the discharge pipe of the compressor, and a refrigerant recovery that connects the outlet pipe of the three-way valve and the suction pipe of the compressor A pipe is provided to switch the three-way valve during the drying operation to allow the refrigerant discharged from the compressor to flow in the order of the reheater, the liquid receiver, and the evaporator, and the refrigerant remaining in the condenser through the refrigerant recovery pipe. It is configured to be collected.

[0011]

With the above-described structure, the refrigerating apparatus of the present invention allows the high-temperature refrigerant discharged from the compressor to directly flow into the reheater during the drying operation, thereby improving the drying capacity. In particular, since the condenser does not pass through during the drying operation, the drying capacity does not decrease even when the outside air temperature is low.

Further, since the refrigerant recovery pipe for connecting the outlet pipe of the three-way valve and the suction pipe of the compressor is provided, the refrigerant in the condenser during the cooling operation can be introduced into the dry operation cycle, and It is possible to prevent the refrigerant from remaining in the container. As a result, there is no need to increase the refrigerant charge amount, and a large capacity refrigeration system can be used.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a refrigerant circuit of the refrigerating apparatus of the present invention. In this device, a compressor 1, a condenser 2, a liquid receiver 3, an expansion valve 4, and an evaporator 5 are connected by piping, and a reheater 6 is provided in parallel with the evaporator 5, and further, the compression is performed. A three-way valve 7 is provided on the discharge side of the machine 1, and a reheating circuit 8 from the three-way valve 7 to the liquid receiver 3 via the reheater 6 is provided. Further, 9 is branched from a pipe between the three-way valve 7 and the condenser 2 and is connected to the compressor 1 via a solenoid valve 10 and a pressure adjusting valve 11.
Is a refrigerant recovery circuit connected to the suction pipe of the. 12 is
The solenoid valve 1 is branched from the reheat circuit 8 on the outlet side of the three-way valve 7.
3 is a bypass circuit connected to the refrigerant recovery circuit 9 in front of the pressure regulating valve 10 via the bypass circuit 3. Reference numeral 14 is a solenoid valve provided on the inlet side of the expansion valve 4, and reference numerals 15 and 16 are check valves. Two
0 and 21 are blowers. Reference numeral 26 is a pilot pipe for the three-way valve 7.

Further, in FIG. 1, the inside of the broken line shows the inside of the outdoor unit, the inside of the chain double-dashed line shows the inside of the drying cabinet, 17 is a temperature sensor, 18 is a humidity sensor, and 19 is a controller for controlling the temperature and humidity in the cabinet. Indicates. The inside of the drying cabinet is dried and cooled to an appropriate temperature and humidity according to the stored items by the control device 19.

In the refrigerating apparatus constructed as above,
During the cooling operation, the refrigerant circulates as shown by the thick line in FIG.
That is, the control device 19 turns off the three-way valve 7 and turns off the solenoid valve 14.
Is controlled so that the solenoid valve 13 is closed, the solenoid valve 13 is closed, and the solenoid valve 10 is closed. The refrigerant discharged from the compressor 1 sequentially flows through the condenser 2, the liquid receiver 3, the expansion valve 4, and the evaporator 5. A cycle for returning to the compressor 1 is configured. As a result, the inside of the drying chamber is cooled to the temperature set by the controller 19.

Next, when switching from the cooling operation to the drying operation, the refrigerant circulates as indicated by the thick line in FIG. That is, the control device 19 controls the three-way valve 7 to be ON, the solenoid valve 14 to be opened, the solenoid valve 13 to be closed, and the solenoid valve 10 to be opened, so that the refrigerant discharged from the compressor 1 is controlled by the three-way valve 7. The reheat circuit 6, the liquid receiver 3, the expansion valve 4, and the evaporator 5 sequentially flow into the reheat circuit 8 to return to the compressor 1. Further, since the solenoid valve 10 is opened, the refrigerant recovery circuit 12 returns the refrigerant remaining in the condenser 2 during the cooling operation to the suction side of the compressor 1 little by little while adjusting the pressure, and the drying operation is performed. The shortage of refrigerant is solved. Here, the solenoid valve 10 is kept open for a fixed time so that all of the residual refrigerant can be collected. Then, the refrigerant is circulated through both the reheater 6 and the evaporator 5, both the reheater 6 and the evaporator are ventilated by the blower 20, and the temperature inside the drying chamber is set by the controller 19. And dried to humidity.

Next, during the drying operation, the refrigerant circulates as indicated by the thick line in FIG. That is, the control device 19 controls the three-way valve 7 to be ON, the solenoid valve 14 to be open, the solenoid valve 13 to be closed, and the solenoid valve 10 to be closed, so that the refrigerant discharged from the compressor 1 is controlled by the three-way valve 7. The reheat circuit 6, the liquid receiver 3, the expansion valve 4, and the evaporator 5 sequentially flow into the reheat circuit 8 to return to the compressor 1. Then, the refrigerant is circulated through both the reheater 6 and the evaporator 5, and the blower 20 causes the reheater 6 to flow.
Both the air conditioner and the evaporator are ventilated so that the controller 19
It is cooled and dried so that the temperature and humidity set in step 1 are reached.

Next, when switching from the drying operation to the cooling operation, the refrigerant circulates as shown by the thick line in FIG. That is, the control device 19 controls the three-way valve 7 to be OFF, the solenoid valve 14 to be open, the solenoid valve 13 to be open, and the solenoid valve 10 to be closed, so that the refrigerant discharged from the compressor 1 is received by the condenser 2 and the receiver. A cooling cycle in which the liquid 3, the expansion valve 4, and the evaporator 5 sequentially flow and are returned to the compressor 1 is configured. At this time, since the solenoid valve 13 is opened, the bypass circuit 12 gradually adjusts the pressure of the refrigerant remaining in the reheater 6 during the drying operation while gradually compressing the refrigerant.
It is returned to the intake side to eliminate the shortage of refrigerant in the dry operation. Here, the solenoid valve 13 is kept open for a certain period of time so that all the residual refrigerant can be recovered. Then, the solenoid valve 13 is closed after a predetermined time, and only the normal cooling operation is performed.

The above three-way valve 7 and solenoid valves 14, 13, 1
To switch 0, the temperature sensor 17 and the humidity sensor 1
It is automatically performed by the control device 19 which is inputting the signal from 8.

In the refrigerating apparatus thus controlled,
During the drying operation, the three-way valve 7 is switched to cause the high-temperature refrigerant discharged from the compressor 1 to directly flow into the reheater 6, and then the liquid receiver 3 and the evaporator 5 are flowed in this order. During the drying operation, the high temperature refrigerant discharged from the compressor 1 can directly flow into the reheater 6, and the drying capacity can be improved. In particular, since the condenser 2 does not pass through during the drying operation, the drying capacity does not decrease even when the outside air temperature is low.

Further, since the refrigerant recovery pipe 8 for connecting the outlet pipe of the three-way valve 7 and the suction pipe of the compressor 1 is provided,
The refrigerant in the condenser 2 can be introduced into the drying operation cycle during the cooling operation, and the refrigerant in the condenser 2 can be prevented from remaining. As a result, there is no need to increase the refrigerant charge amount, and a large capacity refrigeration system can be used.

Further, since a bypass circuit is provided which branches from the reheat circuit 8 on the outlet side of the three-way valve 7 and is connected to the refrigerant recovery circuit 9 before the pressure regulating valve 10 via the solenoid valve 13, the dry operation is performed. At some times, the refrigerant present in the reheater 2 can be introduced into the cooling operation cycle, and the refrigerant remaining in the reheater 6 can be prevented from remaining. As a result, there is no need to increase the refrigerant charge amount, and a large capacity refrigeration system can be used.

The above-described refrigerant recovery is performed by the condenser 2
Moreover, since it is performed from the inlet side of the reheater 6, the liquid refrigerant does not return to the compressor 1 to cause liquid compression. Moreover, since such a refrigerant recovery operation can be performed while continuing the cooling or drying operation, energy saving can be promoted.

FIG. 6 shows another embodiment, in which a check valve 25 is provided between the three-way valve 7 in the reheat circuit 8 and the branch point of the refrigerant recovery circuit 12 to stop the refrigeration system. At times, it is possible to prevent the backflow of the refrigerant from the reheater 6. That is, when the refrigeration system is stopped, the refrigerant in the reheater 6 is compressed by the pressure difference between the three-way valve 7 and the pilot pipe 26 of the three-way valve 7.
And leaks to the suction side of the compressor 1. As a result, leakage continues until the internal pressure of the compressor 1 becomes the same as the internal pressure of the reheater 6, and a large amount of refrigerant is trapped in the compressor 1 and causes forming and liquid compression. Therefore,
By providing the check valve 25, it is possible to prevent the refrigerant from leaking to the suction side of the compressor 1 through the reheat circuit 8, the three-way valve 7, and the pilot pipe 26 when the refrigeration system is stopped, and to prevent forming and liquid compression. It can be prevented. As a result, the number of ON-OFs of the compressor 1 when the pump down operation is stopped can be reduced, and the refrigeration system can be stopped for a long period of time.

The three-way valve 16 prevents the refrigerant from flowing into the reheater 6 during the cooling operation, and the three-way valve 15 prevents the refrigerant from flowing into the condenser 2 during the drying operation.

Further, FIG. 7 also shows another embodiment, in which the compressor 1, the fan 21 of the condenser 2, the three-way valve 7, each solenoid valve 14, when the cooling operation is performed again through the drying operation, the cooling operation is performed again.
The components 13 and 10 are configured to be ON-OFF controlled as shown in FIG. That is, during the refrigerant recovery operation when the cooling operation shown in FIG. 3 is switched to the drying operation, the rotation speed control of the fan 21 is released by the control of the fan control device 28 in FIG. It was designed to drive. As a result, it is possible to prevent a sudden pressure drop in the condenser 2 during the recovery of the refrigerant. That is, at the time of refrigerant recovery when switching from the cooling operation to the drying operation, boiling evaporation of the refrigerant is likely to occur in the condenser 2 and the thermistor (for temperature detection) mounting portion for the fan control device 28 of the condenser 2 is installed. Since the temperature is reduced, the rotation speed of the fan 21 is reduced, which causes a problem that the pressure inside the condenser 2 is rapidly reduced. This problem has an adverse effect such that the refrigerant recovery time becomes long and the amount of uncollected refrigerant increases. Therefore, in the present embodiment, during the refrigerant recovery operation at the time of switching from the cooling operation to the drying operation, the rotation speed control of the fan 21 is released and the fan 21 is operated at the full speed so that the inside of the condenser 2 is rapidly operated. Pressure drop is prevented, steady refrigerant recovery is enabled, and the pressure control valve 11 allows the refrigerant recovery circuit 12 to operate.
It is possible to stabilize the pressure of and to reduce the amount of refrigerant charge by reducing the amount of uncollected refrigerant.

[0028]

As described above, according to the present invention, the high-temperature refrigerant discharged from the compressor can directly flow into the reheater during the drying operation, and the drying capacity can be improved. In particular, since the condenser does not pass through during the drying operation, the drying capacity does not decrease even when the outside air temperature is low.

Further, since the refrigerant recovery pipe for connecting the outlet pipe of the three-way valve and the suction pipe of the compressor is provided, the refrigerant in the condenser can be introduced into the drying operation cycle during the cooling operation, and It is possible to prevent the refrigerant from remaining in the container. As a result, there is no need to increase the refrigerant charge amount, and a large capacity refrigeration system can be used.

[Brief description of drawings]

FIG. 1 is a refrigerant circuit diagram showing a refrigerating apparatus of the present invention.

FIG. 2 is a refrigerant circuit diagram showing refrigerant circulation during a cooling operation.

FIG. 3 is a refrigerant circuit diagram showing refrigerant circulation at the time of switching from the cooling operation to the drying operation.

FIG. 4 is a refrigerant circuit diagram showing refrigerant circulation during a drying operation.

FIG. 5 is a refrigerant circuit diagram showing refrigerant circulation at the time of switching from the drying operation to the cooling operation.

FIG. 6 is a refrigerant circuit diagram showing a refrigeration system of another embodiment.

FIG. 7 is an explanatory view showing the control of the refrigeration system of another embodiment.

FIG. 8 is a refrigerant circuit diagram showing a conventional refrigeration system.

[Explanation of symbols]

 1 Compressor 2 Condenser 3 Liquid receiver 4 Expansion valve 5 Evaporator 6 Reheater 7 Three-way valve 8 Reheat circuit 9 Refrigerant recovery circuit 12 Bypass circuit

Claims (2)

[Claims] 1. A compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and a reheater is provided in parallel with the evaporator, and the reheater and the evaporator are provided during a drying operation. In a refrigerating apparatus in which a refrigerant is allowed to flow in both sides to dry the inside of the refrigerator, a three-way valve is provided in the discharge pipe of the compressor, and the three-way valve is switched during the drying operation to reheat the refrigerant discharged from the compressor. A refrigerating device characterized in that the flow is performed in the order of the liquid receiver, the evaporator, and the evaporator. 2. A compressor, a condenser, a liquid receiver, a decompression device, and an evaporator are connected by piping, and a reheater is provided in parallel with the evaporator, and the reheater and the evaporator are provided during a drying operation. In a refrigerating device in which a refrigerant is allowed to flow in both sides to dry the inside of the refrigerator, a three-way valve is provided in the discharge pipe of the compressor, and a refrigerant recovery that connects the outlet pipe of the three-way valve and the suction pipe of the compressor A pipe is provided to switch the three-way valve during the drying operation to allow the refrigerant discharged from the compressor to flow in the order of the reheater, the liquid receiver, and the evaporator, and the refrigerant remaining in the condenser through the refrigerant recovery pipe. A refrigerating apparatus having a structure for collecting.