JPH04369366A - Cooler - Google Patents

Abstract

PURPOSE:To obtain an efficient defrosting and to minimize the temperature rise in the cooler during defrosting. CONSTITUTION:In an evaporator 1 constituted of a plate fin 2 and a cooling pipe 3 running through the plate fin 2, a condensation pipe 11 is arranged through the plate fin 2 and a communication pipe 12 is also provided which is constituted of a horizontal part pipe 12b in which liquid refrigerant 13 is sealed and a vertical part pipe 12a to which the condensation pipe 11 is connected, so that operation of a heating means 14 is controlled corresponding to pressure inside the communication pipe 12.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to improvements in cooling devices used in refrigerators and the like.

0002

2. Description of the Related Art FIGS. 6 and 7 are a perspective view showing an evaporator of a conventional cooling device and a side view showing a state in which the conventional cooling device is installed in a refrigerator.
An evaporator 4 is composed of a plurality of plate fins 2 and a cooling pipe 3 passing through the plurality of plate fins 2.
5 is a defrosting heater attached to the side surface of a plurality of plate fins 2; 5 is a box fixed to the inner wall of the refrigerator 9; An evaporator 1 is housed on the air inlet 6 side, and a blower 8 is housed on the air outlet 7 side. 10 is a defrosting timer.

Next, the operation will be explained. First, when a cooling operation is performed, the blower 8 is driven, and the air inside the warehouse is sucked in from the air suction port 6 in the evaporator 1 through a condenser (not shown), a throttle device (not shown), and then the evaporator. It exchanges heat with the liquid refrigerant supplied to the refrigerant 1, is cooled, and is blown out from the air outlet 7 into the refrigerator to cool the interior of the refrigerator. When this cooling operation is carried out for a certain period of time and frost forms on the plate fins 2 of the evaporator 1, the defrosting timer 10 is activated and the defrosting heater 4 is energized. At this time, the heat generated from the defrosting heater 4 is conducted to the plate fins 2 of the evaporator 1 and the cooling pipe 3, and defrosting begins. When the frost melts, a thermostat (not shown) that detects the temperature of the evaporator 1 is activated, and defrosting is completed.

0004

[Problems to be Solved by the Invention] Since the conventional cooling device is constructed as described above, defrosting is started by the defrosting timer 10 even if there is not much frost, and the wasted heat is removed from the refrigerator. It was released to Also, when defrosting is finished, evaporator 1
This is done by sensing the temperature near the thermostat installed on the
Problems such as not all the frost melting and ice remaining, making the refrigerator uncool, or defrosting for a long time to melt some of the frost, causing the temperature inside the refrigerator to rise and the temperature of the stored items to rise. was there.

[0005] This invention was made in order to solve the above-mentioned problems, and it is possible to defrost efficiently even if the frost is unevenly formed, and the temperature inside the refrigerator does not rise much during defrosting. The purpose is to obtain a cooling device.

[0006]

[Means for Solving the Problems] A cooling device according to the present invention includes an evaporator composed of plate fins and a cooling pipe passing through the plate fins, and a condensing pipe disposed passing through the plate fins, and A connecting pipe consisting of a vertical piping to which a condensing pipe is connected, and a horizontal piping that communicates with the vertical piping and is disposed at a lower position than the evaporator and has a liquid refrigerant sealed inside, and the horizontal piping. A heating means for heating the liquid refrigerant sealed therein is provided, and the operation of the heating means is controlled according to the pressure inside the communication pipe.

[0007]

[Operation] In the cooling device of the present invention, when frost forms on the evaporator, the pressure inside the connecting pipe decreases, and when the pressure inside the connecting pipe falls below a predetermined value, the heating means is activated by the pressure sensor that detects this, and the heating means is activated to keep the connecting pipe horizontal. The liquid refrigerant sealed in the pipe is heated and evaporated. The heated and evaporated gas refrigerant condenses in the condensing tube and simultaneously heats the condensing tube, and the frost adhering to the evaporator is melted and defrosted by the heat conduction.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A cooling device according to an embodiment of the present invention shown in FIGS. 1 to 5 will be described below. FIG. 1 is a perspective view thereof, FIG. 2 is a cross-sectional view showing essential parts of the present invention, and FIGS. 3 to 5 are cross-sectional views explaining the operation of the present invention. In these figures, 1 is an evaporator composed of a plurality of plate fins 2 and a cooling pipe 3 that passes through the plurality of plate fins 2, and 11 is an evaporator that passes through the plurality of plate fins 2 in the evaporator 1. The arranged condensing pipe 12 is a connecting pipe, and as shown in FIG. 2, the vertical pipe 12a is connected to the condensing pipe 11.
and a horizontal pipe 12b, which is disposed at a lower position than the evaporator 1 and away from the downward projection surface of the evaporator 1, and has liquid refrigerant 13 sealed inside, and a vertical pipe. There is an air pocket 12c (A in the figure) in the upper part of 12a.
dimension section) is provided. 14 is a heater that heats the liquid refrigerant 14, and is connected to the horizontal pipe 12b of the communication pipe 12.
It is fixed to by a fixing fitting 15. Reference numeral 16 indicates a pressure take-off pipe provided in the communication pipe 12, and 17 is connected to the pressure take-off pipe 16. The pressure within the communication pipe 12 is detected through the pressure take-off pipe 16, and when the detected pressure becomes below a predetermined value, the heater 14 is turned on.
energizes and activates it, and when the temperature exceeds a predetermined value, the heater 14
18 is an evaporator inlet pipe, 19 is a distributor, and 20 has one end connected to the cooling pipe 3.
a distribution pipe, the other end of which is connected to the distributor 19;
21 is an evaporator outlet pipe.

Next, the operation will be explained. The liquid refrigerant that has been condensed by a condenser (not shown) and adiabatically expanded by a throttle device (not shown) flows from the evaporator inlet pipe 18 to the cooler 3 via the distributor 19 and distribution pipe 20, and then flows into the evaporator 1. Heat is exchanged with the blown air. The air cooled by this heat exchange is blown out into a cooling space, such as the inside of a refrigerator, to cool the inside of the refrigerator. On the other hand, the refrigerant evaporated and gasified in the evaporator 1 is transferred to the evaporator outlet pipe 21.
and returns to the compressor (not shown). When this cooling operation is continued for a predetermined period of time and frost forms on the plate fins 2 of the evaporator 1, the temperature of the cooler 3 decreases. Therefore, the temperature of the connecting pipe 12 also decreases, and the pressure inside the connecting tube 12 also decreases accordingly. Then, the pressure value detected by the pressure sensor 17 that detects the pressure inside the communication pipe 12 becomes equal to or less than a predetermined value, so that the heater 14 is energized. When the heater 14 is energized, the horizontal portion 12b of the connecting pipe 12
The liquid refrigerant 13 sealed in the evaporates and becomes heated vapor, which passes through the vertical portion 12a of the connecting pipe 12 and into the condensing pipe 1.
I am guided by 1. As a result, the condensing tube 11 is heated, and as shown in FIG.
As shown by the solid arrow, heat is conducted to heat and melt the frost 22 adhering to the cooling pipe 3 and the plate fins 2. Since heating is performed from inside the evaporator 1, the amount of heat leaking to the outside of the evaporator 1 is small. In this way, the liquid refrigerant 13 is evaporated by the heating motor 14 in the horizontal pipe 12b of the communication pipe 12, condensed in the condensing pipe 11 which is a low temperature part, and returned to the horizontal pipe 12b again for defrosting. In addition, when the frost 22 remains unevenly in one part as shown in FIG. 4, the refrigerant moves due to the temperature gradient, so more refrigerant flows concentrated in the low-temperature area, and for example, as shown in FIG. The flow is concentrated in the condensing pipe, increasing the heating power and quickly melting the frost. For this reason, heating power can be used effectively even in the case of uneven frost formation. The end of defrosting is detected when the frost disappears and the pressure inside the connecting pipe 12 rises rapidly, so that the pressure value detected by the pressure sensor 17 exceeds a predetermined value and the power supply to the heater 14 is stopped. The reason why the air pocket 12c shown in FIG. 2 is provided is to remove non-condensable gas, since if the non-condensable gas gets mixed in, it will interfere with condensation in the condensing pipe 11. Furthermore, in the above embodiment, a heater is used as a heating means for heating the liquid refrigerant 13; however,
However, the present invention is not limited to this, and the heating means may be configured such that, for example, a refrigerant pipe is provided in the horizontal pipe 12b to enable heat exchange, and the discharge gas of the compressor is guided to the refrigerant pipe via a solenoid valve. By controlling the opening and closing of the electromagnetic valve using the pressure sensor 17, the operation of the heating means is controlled, and the same effects as those described above can be obtained.

0010

As described above, according to the present invention, an evaporator consisting of a plate fin and a cooling pipe passing through the plate fin is provided with a condensing pipe passing through the plate fin, and A connecting pipe consisting of a horizontal pipe in which refrigerant is sealed and a vertical pipe to which the condensing pipe is connected is provided, and the liquid refrigerant sealed in the horizontal pipe is heated according to the internal pressure of the connecting pipe. Since the heated steam is guided to the condensing pipe to heat the condensing pipe and melt the frost adhering to the cooling pipe and the plate fins by heat conduction, defrosting is started before frost formation. Even if the frost builds up unevenly, it can be defrosted efficiently, defrosting is done in a short time, no wasted heat is released into the cooling space, and the temperature rise in the cooling space is reduced, etc. There is an effect.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a cooling device according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part according to an embodiment of the present invention.

FIG. 3 is a sectional view showing the operation of an embodiment of the present invention.

FIG. 4 is a sectional view showing the operation of an embodiment of the present invention.

FIG. 5 is a sectional view showing the operation of an embodiment of the present invention.

FIG. 6 is a perspective view showing the main parts of a conventional cooling device.

FIG. 7 is a sectional view showing a state in which a conventional cooling device is installed in a refrigerator.

[Explanation of symbols]

1 Evaporator 2 Plate fin 3 Cooling pipe 11 Condensing pipe 12 Connecting pipe 12a Vertical piping 12b Horizontal piping 13 Liquid refrigerant 14　Heating heater 16 Pressure outlet 17 Pressure sensor

Claims (1)

[Claims] 1. A cooling device comprising an evaporator configured with a plate fin and a cooling pipe passing through the plate fin, wherein a condensing pipe provided in the evaporator passing through the plate fin; A connecting pipe consisting of a vertical piping to which a condensing pipe is connected, and a horizontal piping that communicates with the vertical piping and is disposed at a lower position than the evaporator and has a liquid refrigerant sealed inside, and the horizontal piping. A cooling device comprising a heating means for heating a liquid refrigerant sealed therein, and a pressure sensor for detecting the pressure inside the communication pipe and controlling the operation of the heating means according to the detected pressure.