JPH0650647A - Operating method for refrigerator - Google Patents

Abstract

PURPOSE:To shorten the time required for a pull-down in a chill mode by operating an evaporator fan at a low speed until a temperature of an area to be cooled reaches a set temperature or a predetermined set value set close to the set temperature at the time of the pull-down in the chill mode. CONSTITUTION:When a control is started, a set temperature of the air in a refrigerator is set, an operation switch of the refrigerator is closed to detect a temperature of the air in the refrigerator. Then, whether it is a chill mode or not is judged. In the case of yes, an evaporator fan is operated at a low speed. Thereafter, whether a temperature in the refrigerator reaches the set temperature or not is judged. In the case of yes, the fan is switched to a high speed operation. In the case of a frozen mode, the fan is operated at a low speed. Thus, the time required for a pull-down in a chill mode can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of operating a refrigerating unit for containers and the like.

[0002]

2. Description of the Related Art A conventional container is shown in FIG.
The container 1 has a rectangular parallelepiped shape, and a refrigeration unit 100 is attached to one end wall 2 of the container 1. By storing a cargo in the container 1 through a door (not shown) provided on the other end wall of the container 1 and operating the refrigeration unit 100, the air temperature inside the container 1 is kept within the range of -25 ° C to + 25 ° C. The container 1 is carried on a vessel, a truck, a railroad vehicle, etc., while being maintained at a temperature arbitrarily set by.

A schematic structure of the refrigeration unit 100 is shown in FIG. 5, where (A) is a front view, (B) is a sectional view taken along the line BB of (A), and (C) is (B). It is sectional drawing which follows CC arrow. The gas refrigerant discharged from the compressor 3 enters the water cooling condenser 5 or the air cooling condenser 4 and is condensed and liquefied there. The liquid refrigerant enters the electronic expansion valve 9 through the dryer 7 and the strainer 8 and is throttled there to undergo adiabatic expansion to become a gas-liquid two-phase refrigerant. This refrigerant enters the evaporator 10, where it evaporates and vaporizes by cooling the air in the refrigerator blown from the evaporator fan 12 driven by the motor 11. Then, this gas refrigerant returns to the compressor 3 via the accumulator 13.

As shown by the solid arrow, the air in the container 1 enters the evaporator section 15 from the suction port 14 and is urged by the evaporator fan 12, and is cooled in the process of passing through the evaporator 10. Wind path 16, blowout room
It returns to the inside of the container 1 via 18 and is blown out from the gap of many T rails 43.

When the air-cooled condenser 4 is used, the motor
The condenser fan 6 is driven by 17. Then, after the temperature of the outside air is increased by exchanging heat with the gas refrigerant in the process of passing through the air-cooled condenser 4, as indicated by the dashed arrow,
The capacitor fan 6 is energized and discharged.

When using the water-cooled condenser 5, a water supply valve and a drain pipe (not shown) are connected to the cooling water inlet 19 and the cooling water outlet 20 to open the water control valve 21. Then, the cooling water supplied from the water supply pipe enters the water cooling condenser 5 through the water pipe (not shown) from the cooling water inlet 19 and heats up there by exchanging heat with the gas refrigerant. The water is discharged from the cooling water outlet 20 through the water valve 21 and the drain pipe.

The drain condensed on the evaporator 10 is dropped on the drain pan 22 and is passed through the drain hose 23 to the drain port.
Emitted from 24.

Reference numeral 41 denotes an inner and outer partition wall made of a heat insulating material, which is fastened to the end wall 2 of the container 1 by a flange formed on the entire circumference thereof. A condenser section 42 is formed at the center of the lower part on the outside of the heat insulating wall 41, an evaporator section 15 is provided on the upper side of the condenser section 42, an air passage 16 is blown on both sides of the inner and outer partition wall 41, and blown to the lower side. Each chamber 18 is formed. An evaporator 10, an evaporator fan 12, etc. are installed in the evaporator section 15. In the condenser section 42, the compressor 3,
An air-cooled condenser 4, condenser fan 6 and the like are installed.

Reference numeral 25 is a control box, 26 is a solenoid valve for liquid injection for injecting and cooling a liquid refrigerant into the compressor 3, 27 is a 200V class power plug,
28 is a 400V class power supply plug, 29 is a power transformer, 31 is an intake air temperature sensor for detecting the temperature of the air in the refrigerator that is sucked into the evaporator 10, 30 is an insertion port of a thermometer for checking the temperature sensor 31, 33 is a blown air temperature sensor for detecting the temperature of the air blown from the evaporator 10, 32 is an insertion port of a thermometer for checking the temperature sensor 33, and 34 is an outlet for detecting the refrigerant outlet temperature of the evaporator 10. A temperature sensor, 35 is an overheat prevention sensor, 36 is a discharge pipe temperature sensor for detecting the temperature of the discharge pipe of the compressor 3, 37 is an outside air temperature sensor for detecting the temperature of the outside air flowing into the air cooling condenser 4, and 38 is An inspection lid for inspecting the equipment in the evaporator section 15, 39 is a handle for attaching and detaching the inspection lid 38, and 40 is a ventilation device.

When refrigerated cargo is stored in the container 1,
That is, in the chill mode, the set temperature of the inside air is set to a predetermined value (for example, -5 ° C) or more, and the evaporator fan 12 is operated at high speed in order to keep the temperature distribution inside the container 1 uniform. On the other hand, when the frozen cargo is stored in the container 1, that is, in the frozen mode, the set temperature of the internal air temperature is set to a predetermined value (for example, -5 ° C) or less, and even if the temperature distribution in the container 1 is bad, it poses a problem. Therefore, the evaporator 12 is operated at a low speed.

[0011]

In the above conventional refrigeration unit, when pulling down in the chill mode, that is, when the air inside the container 1 is pulled down, the evaporator fan 12 operates at high speed until the inside temperature drops to a predetermined value. Therefore, the internal temperature changes as shown in FIG. 6 over time. Then, as shown in FIG. 7, the refrigerating capacity of the refrigerating unit becomes smaller than that at low speed operation because heat is largely radiated from the fan motor 11 during high speed operation of the evaporator fan 12. As a result, there is a problem that the pull-down time in the chill mode becomes long.

[0012]

SUMMARY OF THE INVENTION The present invention has been invented to solve the above-mentioned problems, and its gist is to operate at high speed in a chill mode in which a set temperature of a cooled region is a predetermined value or more. In a refrigeration unit equipped with an evaporator, which is operated at a low speed in the frozen mode where the set temperature is lower than a predetermined value, the temperature of the cooled area is set to or near the above set temperature when pulling down in the chill mode. A method of operating a refrigeration unit is characterized in that the evaporator tank is operated at a low speed until the value is reached, and after the set temperature or set value is reached, the evaporator fan is switched to a high speed operation.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT One embodiment of the present invention is shown in FIGS. As shown in FIG. 1, when the control starts, in step, the set temperature Ts of the inside air is set, the operation switch of the refrigeration unit 100 is turned on, and the temperature T of the inside air is detected. Next, in step, it is determined whether or not the chill mode is set, that is, whether or not the set temperature Ts is equal to or higher than a predetermined value (for example, -5 ° C). In that case, the evaporator 12 is operated at a low speed in the step. Next, at step, it is judged if the internal temperature T has reached the set temperature Ts. If not, the process returns to the step, but in the other case, the evaporator fan 12 is switched to the high speed operation in the step. If it is determined to be no in the step, that is, if the frozen mode is selected, the evaporator 12
Is driven at low speed. Control ends after step and step.

When pulling down in the chill mode,
The temperature T in the chamber changes as shown by the solid line in FIG. 2, and the time required for pulling down is clear as compared with the conventional one shown by the broken line (the evaporator 12 is always operated at high speed after the start of operation). (Time required for lowering the internal temperature T to the set temperature Ts) is t ₁ , which can be greatly shortened compared to the conventional t ₂ .

In the frozen mode, the evaporator fan 12 is always operated at a low speed after the start of operation, so the temperature T in the refrigerator changes as shown in FIG.

In the above embodiment, the evaporator / fan 12 is switched to high speed operation when the temperature T in the refrigerator reaches the set temperature Ts. However, when it is necessary to avoid overshooting the temperature T in the refrigerator, A set value Tc having a temperature slightly higher than the set temperature Ts is provided in the vicinity of the set temperature Ts, and when the internal temperature T reaches the set value Tc, the evaporator fan 12
Can also be switched to high speed operation.

[0017]

In the present invention, when pulling down in the chill mode, the evaporator is operated at a low speed until the temperature of the cooled area reaches the set temperature or a predetermined set value set in the vicinity thereof. -The heat release from the Tafuan drive motor is reduced, and the refrigeration capacity of the refrigeration unit is increased, so that the time required for pulling down in the chill mode can be shortened.

[Brief description of drawings]

FIG. 1 is a control flowchart showing an embodiment of the present invention.

FIG. 2 is a diagram showing a change over time in the internal cold storage temperature during pull-down in the chill mode of the above embodiment.

FIG. 3 is a diagram showing a change over time in the internal cold storage temperature during pulldown in the frozen mode of the above embodiment.

FIG. 4 is a schematic perspective view of a conventional container.

FIG. 5 shows a schematic configuration of a conventional container refrigeration unit, (A) is a front view, (B) is a cross-sectional view taken along the line BB of (A), and (C) is (B). It is sectional drawing which follows CC arrow.

FIG. 6 is a diagram showing a temporal change of the internal cold storage temperature during pull-down in the conventional chill mode.

FIG. 7 is a diagram showing the relationship among the refrigerating capacity, the temperature inside the refrigerator, and the operating speed of the evaporator.

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[Procedure amendment]

[Submission date] October 29, 1992

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Change

[Correction content]

[Figure 5]

Claims (1)

[Claims] 1. A refrigeration unit equipped with an evaporator, which is operated at a high speed in a chill mode in which a set temperature of a region to be cooled is a predetermined value or higher, and is operated in a low speed in a frozen mode in which a set temperature is a predetermined value or lower, in a chill mode. At this time, the evaporator fan is operated at a low speed until the temperature of the cooled region reaches a predetermined set value set at or near the set temperature, and after reaching the set temperature or set value, the evaporator is set. A refrigeration unit operating method characterized by switching the Tafuan to high-speed operation.