JPH09189460A - Refrigerating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drop an absolute moisture inside a refrigerator to a satisfactory extent without increasing power consumption by setting up a heating coil on the downstream side of a vaporizer of an air flow passage and introducing hot gas in a refrigeration circuit into this heating coil SOLUTION: An air circulation fan 12, an air cooling vaporizer 10, a heating coil 64 and a heater 45 are set up in an air flow passage 15 of an in- compartment air. The vaporizer 10 and the heating coil 64 are slanted at least by 30 deg. substantially in the same direction. The heating coil 64 is set up on the downstream side of the vaporizer 10 with a spacing separated therefrom. The heating coil 64 is interposed in a hot gas bypass circuit where a modulating valve is interposed on the inlet side of the heating coil 64. When the modulating valve is opened, the high temperature and high pressure hot gas compressed with a compressor flows partially into the hot gas bypass circuit so that it may flow into the vaporizer 10 by way of the modulating valve and the heating coil 64.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a refrigerating apparatus suitable for containers and the like.

[0002]

2. Description of the Related Art A container stores cargo inside and operates a refrigerating apparatus to increase the temperature inside the container from -25 ° C to +
It is transported by being loaded on ships, trucks, railway vehicles, etc. while maintaining the temperature set arbitrarily within the range of 25 ° C.

A system diagram of this refrigerating apparatus is shown in FIG. When the refrigeration system is operated, the gas refrigerant discharged from the compressor 1 enters the condenser 2 where it is condensed and liquefied. The liquid refrigerant enters the expansion valve 3 and is throttled there to adiabatically expand into a gas-liquid two-phase refrigerant. This refrigerant enters the evaporator 4, where it evaporates and vaporizes by cooling the in-compartment air blown by the fan 5, and then returns to the compressor 1.

A modulating valve 8 is interposed in a hot gas bypass circuit 7 which connects the outlet of the compressor 1 and the inlet of the evaporator 4. The evaporator 4 and the fan 5 and the motor 6 for driving the same are installed in the air flow path 9 for the air inside the container formed in the container C, and a plurality of (six in the figure) downstream of the evaporator 4 are provided. An electric heater H is provided.

When the refrigerated cargo such as fresh fruits is stored in the container C, the fan 5 is operated at a high speed, and the modulating valve 8 is opened and closed while the compressor 1 is continuously operated to adjust the capacity of the refrigeration system. By doing so, the internal temperature is maintained within the set temperature ± 0.2 ° C, for example.

When a frozen cargo such as frozen tuna is stored in the container C, the fan 5 is operated at a low speed. Then, the compressor 1 is stopped when the internal temperature decreases and reaches the lower set temperature, and when the internal temperature rises and reaches the upper set temperature, the compressor 1 is operated to change the internal temperature, for example. Keep the temperature within ± 3 ℃.

When a large amount of frost adheres to the evaporator 4 and when the temperature inside the refrigerator is raised, the compressor 1 is stopped and the electric heaters H are energized while operating the fan 5.

When the humidity inside the refrigerator is to be lowered, the two electric heaters H are energized while the fan 5 and the compressor 1 are operated, and the evaporator 4 is cooled to cool the inside air. The absolute humidity of the air in the refrigerator is lowered by condensing water, and the relative humidity is lowered by heating the air with the electric heater H.

[0009]

In the above conventional refrigerating apparatus, since it is necessary to energize the electric heater H in addition to the compressor 1 and the fan 5 during the dehumidifying operation, not only the power consumption increases. Since the cooling capacity of the evaporator 4 has to be controlled in order to maintain the internal temperature at the set temperature, there has been a problem that the absolute humidity cannot be reduced sufficiently by that amount.

[0010]

SUMMARY OF THE INVENTION The present invention has been invented to solve the above-mentioned problems, and its gist is to provide a fan for circulating air in an air flow path of the inside air and In a refrigerating apparatus having an evaporator for cooling air, a heating coil is installed in the air passage downstream of the evaporator, and hot gas in a refrigerant circuit is introduced into the heating coil to heat air. A refrigeration system characterized by the above.

Thus, the air in the refrigerator is cooled by passing through the evaporator, and then heated by passing through the heating coil.

[0012] The evaporator may be arranged in a tilted manner with a spacing from the heating coil.

The heating coil may be provided in the hot gas bypass circuit of the refrigerant circuit, and a modulating valve may be provided on the refrigerant inlet side to control the hot gas bypass amount to adjust the temperature of the blown air to a preset temperature.

A circuit for flowing the liquid refrigerant passing through the condenser and the expansion means in parallel to the evaporator and the heating coil, a circuit for flowing the liquid refrigerant passing through the condenser and the expansion means to the evaporator, and hot gas are provided. A circuit and a switching valve for selecting a circuit to be passed through the heating coil can be provided.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIGS. As shown in FIG. 1, a fan 12 for air circulation, an evaporator 10 for air cooling, a heating coil 64, and a heater 45 are installed in an air flow path 15 for the inside air. The evaporator 10 and the heating coil 64 are inclined in the same direction by at least 30 ° C. or more, and the heating coil 64 is installed on the downstream side of the evaporator 10 at intervals. A heater 45 having a smaller capacity than the conventional one is installed downstream of the heating coil 64.

The drain pan 42 is biased toward the lower end side of the evaporator 10.
Is fixed to the inner / outer partition wall 41, and the drain pipe 43 connected to the drain pan 42 extends downward through the inner / outer partition wall 41, and a U-shaped bent portion 44 is formed at the lower end thereof.

As shown in FIG. 2, the heating coil 64 is provided in the hot gas bypass circuit 62, and the modulating valve 63 is provided at the inlet side of the heating coil 64.

However, when the fan 12 is driven by the motor 11, the air inside the chamber is urged by the fan 12 and circulates in the air flow path 15, and the evaporator 10, the heating coil 64 and the heater 45.
Are passed through in this order and sent to the warehouse.

On the other hand, when the compressor 13 is operated, this compressor is
The high-temperature, high-pressure gas refrigerant compressed in 13 is expanded in the condenser 14 and is throttled by the expansion valve 61 to be adiabatically expanded.
After evaporating at 10, it is sucked into the compressor 13.

When the modulating valve 63 is opened, a part of the high temperature and high pressure hot gas compressed by the compressor 13 enters the hot gas bypass circuit 62, and passes through the modulating valve 63 and the heating coil 64 to the evaporator 10. Inflow.

Thus, the dehumidifying capacity of the evaporator 10 can be adjusted to the maximum by controlling the amount of the refrigerant flowing through the evaporator 10 by the expansion valve 61. Further, the temperature of the air blown from the heating coil 64 can be adjusted to the set temperature by controlling the amount of hot gas flowing through the heating coil 64 by the modulating valve 63.

As a result, the absolute humidity can be lowered by making the evaporator 10 exhibit the maximum dehumidifying capacity, and the relative humidity can be lowered by heating the air by the heating coil 64. It is possible to effectively reduce the humidity in the refrigerator without energizing.

Further, since the evaporator 10 is installed so as to be inclined and the heating coil 64 is installed at a distance from the evaporator 10, the drain condensed in the evaporator 10 travels under the evaporator 10 to the drain pan 42. Drop it. Therefore, since the drain does not drip to the heating coil 64, it is possible to prevent the drain from being evaporated by being heated by the heating coil 64 and elevating the humidity in the refrigerator.

A second embodiment of the invention is shown in FIG. In the second embodiment, a three-way modulating valve 65 is provided on the discharge side of the compressor 13, and when the three-way modulating valve 65 is closed, the compressor is closed.
The hot gas discharged from 13 is guided to the condenser 14,
When opened, the hot gas is hot gas bypass circuit 62,
The heating coil 64 passes through the heating coil 64 in this order and flows into the condenser 14. Other configurations are similar to those of the first embodiment shown in FIGS. 1 and 2, and corresponding members are designated by the same reference numerals and the description thereof will be omitted.

In the second embodiment, however, when the three-way modulating valve 65 is opened, the heating coil 64 functions as a condenser, so that the dehumidifying capacity of the evaporator 10 is the same as that of the first embodiment. Since it increases more than the above, it is possible to further reduce the humidity in the refrigerator.

A third embodiment of the invention is shown in FIG. In the third embodiment, a modulating valve 63 is provided on the inlet side of the condenser 14, and the amount of hot gas flowing into the condenser 14 can be controlled by adjusting the opening degree. However, other configurations and operations are similar to those of the second embodiment shown in FIG. 3, and corresponding members are designated by the same reference numerals.

A fourth embodiment of the present invention is shown in FIGS. In the fourth embodiment, the expansion valve
A pipe 66 for connecting the refrigerant pipe connecting 61 to the evaporator 10, the modulating valve 63 and the hot gas bypass circuit 62 connecting the heating coil 64 is provided, and an electromagnetic opening / closing valve is provided in this pipe 66.
67 are installed. Other configurations are similar to those of the first embodiment shown in FIGS. 1 and 2, and corresponding members are designated by the same reference numerals and the description thereof will be omitted.

However, as shown in FIG. 6, during the maximum cooling operation, the expansion valve 61 and the electromagnetic on-off valve 67 are opened and the modulating valve MV is closed, so that the refrigerant discharged from the compressor 13 is condensed. 14.Branch through the expansion valve 61, and most of it branches into the evaporator 10.
7. After passing through the hot gas bypass circuit 62 and the heating coil 64 in this order, the hot gas bypass circuit 62 and the heating coil 64 merge with the flowing refrigerant in the evaporator 10 and then are sucked into the compressor 13.

Expansion valve during dehumidification operation and capacity control operation
61, the modulating valve MV is opened, and the electromagnetic opening / closing valve 67 is closed, so that the refrigerant discharged from the compressor 3 immediately branches, and most of the refrigerant passes through the condenser 14 and the expansion valve 61 and the evaporator 10
A part of the gas flows through the hot gas bypass circuit 62, the modulating valve 63, and the heating coil 64 in this order, merges with the refrigerant branched before, and is then sucked into the compressor 13.

Thus, in the fourth embodiment, the absolute humidity can be effectively lowered by cooling the air inside the refrigerator by the evaporator 10 and the heating coil 64 during the maximum cooling operation, and the dehumidifying operation can be performed. At the time and during the capacity control operation, the air cooled by the evaporator 10 is heated by the heating coil 64 so that the internal temperature can be maintained at the set temperature and the relative humidity can be lowered, so that it is not necessary to energize the heater 45. .

A fifth embodiment of the present invention is shown in FIGS. The fifth embodiment has the same structure as the fourth embodiment shown in FIG. 5 except that the electromagnetic opening / closing valve 68 is provided on the inlet side of the heating coil 64. Then, during maximum cooling operation, capacity control operation, and dehumidification operation, expansion valve 61 and modulating valve, respectively.
The MV and electromagnetic on-off valves 67 and 68 are opened and closed as shown in FIG.

In the fifth embodiment, since the opening degree of the expansion valve 61 can be narrowed during the capacity control operation, the power consumption can be further reduced.

[0033]

According to the present invention, the inside air is cooled by passing through the evaporator and then heated by passing through the heating coil. Therefore, the evaporator is allowed to exhibit the maximum dehumidifying capacity. In addition, the relative humidity can be reduced by the heating coil. As a result, it is possible to maintain the humidity of the inside air at a low temperature while maintaining the humidity at the set temperature.

If the evaporator is inclinedly arranged at a distance from the heating coil, the drain condensed by the evaporator does not drip on the heating coil, so that the drain is re-evaporated by the heating coil and the humidity of the inside air increases. Can be prevented.

If the heating coil is provided in the hot gas bypass circuit and a modulating valve for controlling the hot gas bypass amount to adjust the temperature of the blown air to the set temperature is provided on the refrigerant inlet side, the heating coil blows out from the heating coil. The air temperature to be maintained can be maintained at the set temperature.

A circuit for flowing the liquid refrigerant passing through the condenser and the expanding means in parallel to the evaporator and the heating coil, a circuit for flowing the liquid refrigerant passing through the condenser and the expanding means to the evaporator, and heating the hot gas. By providing a circuit for selecting a circuit to be passed through the coil and a switching valve, the dehumidifying operation and the capacity control operation can be efficiently performed without energizing the heater.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a first embodiment of the present invention.

FIG. 2 is a refrigerant circuit diagram of the first embodiment.

FIG. 3 is a refrigerant circuit diagram showing a second embodiment of the present invention.

FIG. 4 is a refrigerant circuit diagram showing a third embodiment of the present invention.

FIG. 5 is a refrigerant circuit diagram showing a fourth embodiment of the present invention.

FIG. 6 is a chart showing a relationship between an operation mode and opening / closing of an expansion valve, a modulating valve, and an opening / closing valve in the fourth embodiment.

FIG. 7 is a refrigerant circuit diagram showing a fifth embodiment of the present invention.

FIG. 8 is a chart showing a relationship between an operation mode and opening / closing of an expansion valve, a modulating valve, and an opening / closing valve in the fifth embodiment.

FIG. 9 is a schematic configuration diagram of a conventional refrigeration system.

[Explanation of symbols]

 15 Air flow path 12 Juan 10 Evaporator 64 Heating coil

Claims (4)

[Claims] 1. A refrigerating apparatus in which a fan for air circulation and an evaporator for cooling air are installed in an air flow path of the air in the refrigerator, and a heating coil is installed on the downstream side of the evaporator in the air flow path. Then
A refrigerating apparatus, wherein hot gas in a refrigerant circuit is introduced into the heating coil to heat air. 2. The refrigerating apparatus according to claim 1, wherein the evaporator is inclinedly arranged at a distance from the heating coil. 3. The heating coil is provided in a hot gas bypass circuit of the refrigerant circuit, and a modulating valve is provided on the refrigerant inlet side of the refrigerant circuit to control the amount of hot gas bypass to adjust the temperature of blown air to a preset temperature. The refrigerating apparatus according to claim 1 or 2, characterized in that. 4. With respect to the evaporator and the heating coil,
A circuit for selecting a circuit for flowing the liquid refrigerant that has passed through the condenser and the expansion means in parallel, and a circuit that causes the liquid refrigerant that has passed through the condenser and the expansion means to flow to the evaporator and a circuit that causes hot gas to flow to the heating coil. 4. The refrigerating apparatus according to claim 1, further comprising a switching valve.