JPS62147274A - Refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a defrosting system for a refrigeration device that is used in a refrigerator or the like and is accompanied by sardine deposition.

BACKGROUND OF THE INVENTION In recent years, tube heaters have been increasingly used for defrosting the evaporators of refrigerator refrigeration equipment, using low-cost radiant heat.

An example of a conventional refrigeration system will be described below with reference to the drawings. FIG. 2 shows a system diagram of a conventional refrigeration system. 1 is a rotary compressor, 2 is a condenser, 3 is a capillary tube, and 4 is an evaporator. The refrigeration system includes the rotary compressor 1. Capacitor 2, capillary tube 3. The evaporators 4 are connected in series. 6 is an on-off valve that opens and closes in conjunction with 0N10FF of the rotary compressor 1. 6 is a check valve which is opened by the refrigerant flow when the rotary compressor 1 is in operation, and closed by the valve's own weight when the rotary compressor 1 is stopped.

The evaporator 4 is constructed by bending a finned refrigerant pipe 4a into a meandering shape, and is installed inside a refrigerator (not shown) so that the airflow inflow side A is at the bottom. 7 is an accumulator. 8 is a defrosting tube heater. The defrosting tube heater 8 is provided near the bottom of the evaporator 8.

The operation of the refrigeration system configured as described above will be explained below.

First, during cooling operation, open/close valve 5. The check valve 6 is opened and the rotary compressor 1. Capacitor 2゜Capillary tube 3. The evaporator 4 and the refrigerant flow, and the evaporator 4
to cool a refrigerator (not shown). When cooling is stopped,
Open/close valve 5. The check valve 6 is closed, and the rotary compressor 1. This prevents the high temperature refrigerant in the condenser 2 from flowing into the evaporator 4 through the capillary tube 3 and causing a heat load. Then, the refrigerant operation and stop are repeated to cool the refrigerator (not shown) to a predetermined temperature. Also, since frost forms on the evaporator 4, the rotary compressor 1 is periodically stopped, the defrosting tube heater 8 is energized and heated, and the heat rays radiated from the defrosting heater 8 prevent frost from forming on the evaporator 4. This is to defrost the frost that is present.

Problems to be Solved by the Invention However, with the above configuration, the radiant heat of the defrost pipe heater 8 does not reach the upper part of the evaporator 4 sufficiently during defrosting, so the temperature of the upper part of the evaporator 4 is lower than that of the evaporator 4.
The temperature rises slower than the temperature at the lower part of the evaporator 4, and in order to prevent the frost on the upper part of the evaporator 4 from melting, it is necessary to heat the lower part of the evaporator 4 more than necessary, making the defrosting efficiency of the evaporator 4 inefficient. Ta.

Therefore, the present invention aims to equalize the heating temperature during defrosting of the evaporator and shorten the defrosting time.

Means for Solving the Problems In order to solve the above problems, the refrigeration system of the present invention includes a single finned refrigerant pipe arranged in a meandering shape to form an evaporator, and the evaporator is arranged so that the airflow inflow side is at the bottom. A defrosting heater is installed at the bottom of the evaporator, an on-off valve is provided at the inlet and outlet of the evaporator that closes during defrosting, and a communicating pipe is provided that bypasses the inlet and outlet of the evaporator. It is equipped with a check valve.

Operation According to the above-described structure, the on-off valves at the inlet and outlet of the evaporator are closed during defrosting, so that the evaporator and the communication pipe have the same structure as a single open-loop thermosiphon, and the evaporator The refrigerant inside the evaporator is heated by the defrost heater at the bottom and evaporates efficiently inside the evaporator.

Since condensation is carried out, the temperature rise during defrosting of the evaporator can be equalized and accelerated, and the defrosting time can be shortened.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIG. FIG. 1 shows a system diagram of the refrigeration apparatus of the present invention. 9 is a rotary compressor, 10 is a condenser, 11 is a capillary tube, and 12 is an evaporator. Refrigeration system c, the rotary compressor 9
, capacitor 10, capillary tube 11. The evaporators 12 are connected in series. 13 is on-off valve A
It opens and closes in conjunction with the 0N10FF of the rotary compressor 9. Reference numeral 14 denotes an on-off valve B, which opens and closes in conjunction with the ○N10 FF of the rotary compressor 9, similar to the on-off valve A13. The evaporator 12 is constructed by bending a finned refrigerant pipe 12a in a meandering dogleg shape, and is installed inside a refrigerator (not shown) with the airflow inflow side A at the bottom.

Reference numeral 16 denotes an accumulator, which is installed at the bottom of the evaporator 12 so that the downstream side of the flow of refrigerant is at the top.

Reference numeral 16 denotes a communicating pipe that communicates the inlet and outlet of the evaporator 12, and the communicating pipe 16 is provided with a check valve 17. 18
The defrosting heater is a PTC heater with a self-temperature control function. The defrosting heater 18 is attached to the accumulator 16 for heat exchange.

The operation of the refrigeration system configured as described above will be explained below.

First, during cooling operation, the on-off valve A13 and the on-off valve B14 are opened, and the rotary compressor 9. Capacitor 10.
Capillary tube 11. The refrigerant flows to the evaporator 7 and 12, and the evaporator 12 cools the refrigerator (not shown). At this time, the check valve 17 is closed by the refrigerant flow, and no refrigerant flows through the communication pipe 16. When cooling is stopped, open/close valve A13. The on-off valve B14 is closed to prevent the high temperature refrigerant in the o-tally compressor 9 and condenser 10 from flowing into the evaporator 12 through the capillary tube 11 and causing a heat load. The refrigerator (not shown) is cooled to a predetermined temperature by repeating the cooling operation and stopping described above. When the rotary compressor 9 operates for a certain period of time, defrosting is automatically performed. When defrosting, first the rotary compressor 9 is stopped. The high temperature refrigerant in the rotary compressor 9 and condenser 10 then flows into the evaporator 12 and accumulates in the accumulator 16 as liquid refrigerant. After a predetermined period of time has elapsed, the on-off valve A13. The on-off valve B14 is closed and the defrosting heater 18 is energized. The liquid refrigerant in the accumulator 16 is heated by the defrosting heater 18 and evaporates. On-off valves A are installed at the inlet and outlet of the evaporator 12, respectively.
13. Since the on-off valve B14 is provided and the circuit is closed, the heated high-temperature gas refrigerant passes through the check valve 17 and inside the finned refrigerant pipe 12a, and is cooled and condensed by melting the frost attached to the surface of the evaporator 12. It turns into a liquid, flows down inside the finned refrigerant pipe 12a due to its own weight, and returns to the accumulator 15. The returned liquid refrigerant is heated again by the defrosting heater 18, evaporates, and enters the finned refrigerant pipe 12a through the check valve 17. By repeating the above-mentioned operations, the defrosting heater 18 installed thermally conductively at one side of the accumulator at the bottom of the evaporator 12
The heat is effectively and quickly transferred throughout the evaporator 12 to defrost in a short time.

As mentioned above, the on-off valve A13 at the inlet and outlet of the evaporator 12 during defrosting. After a predetermined period of time has elapsed, the on-off valve B14 is closed, and
By connecting the communication pipe 16 with a check valve 17 between the inlet and outlet of the evaporator 12, the evaporator 12 and the communication pipe 16 have the same structure as a single open loose thermosiphon, and the accumulator 16 is connected to the refrigerant. Since it is used as a liquid storage container and the defrosting heater 18 is provided in the accumulator 15 for heat exchange, the defrosting heater 18
The heat is efficiently conducted to the accumulator 16, and the high-temperature refrigerant heated in the accumulator 15 circulates in the evaporator 12 at high speed, making the temperature rise uniform and faster during defrosting of the evaporator. Effect of the invention that can shorten frost time As described above, the present invention has an evaporator formed by forming a single finned refrigerant pipe in a meandering shape, and arranging the evaporator so that the air flow inflow side is at the bottom. A defrosting heater is provided at the bottom of the evaporator, and on-off valves are provided in the refrigerant circuits at the inlet and outlet of the evaporator, which open and close in conjunction with the ON and OFF of the compressor and close during defrosting. A communication pipe is provided to bypass the evaporator, and a check valve is provided on the communication pipe. Therefore, during defrosting, the evaporator has the same configuration as a single open-loop thermosiphon, and the defrost heater at the bottom of the evaporator The refrigerant inside the evaporator is heated and circulates through the evaporator at high speed.
Since evaporation rises and condensation falls efficiently, the temperature rise during defrosting of the evaporator can be made more uniform and faster, and the defrosting time can be shortened.

[Brief explanation of drawings]

FIG. 1 is a diagram of a cooling system of a refrigeration system showing an embodiment of the present invention, and FIG. 2 is a diagram of a cooling system of a conventional refrigeration system. 9...Rotary compressor, 10...
... Capacitor, 11 ... Capillary tube, 12 ... Evaporator, 12a ...
Fined refrigerant pipe, 13... Open/close valve A, 14...
...Opening/closing valve B, 16...Communication pipe, 17...
...Check valve, 18...Defrosting heater.

Claims (1)

[Claims] This is a refrigeration system in which a rotary compressor, a condenser, and a capillary tube evaporator are connected in sequence, and the evaporator has a single finned refrigerant tube arranged in a meandering shape so that the airflow inflow side is at the bottom, and the bottom of the evaporator is used for defrosting. A heater is provided, an on-off valve is provided in the refrigerant circuit at the inlet and outlet of the evaporator, and an on-off valve that opens and closes in conjunction with ON and OFF of the compressor and is closed during defrosting, and a communication pipe is provided that bypasses the inlet and outlet of the evaporator. A refrigeration system with a reverse valve installed in the communication pipe.