JP2000274842A - Refrigerating circuit and refrigerator using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress energy consumption used to heat a sucked refrigerant and to improve cooling capabilty by providing a heat exchanger for heat exchanging a suction tube for connecting an evaporator to a compressor in a refrigerating circuit, and a heating means for further heating the refrigerant passed through the exchanger. SOLUTION: A refrigerant evaporated and vaporized by an evaporator 4 is sucked to a compressor 1 through a suction refrigerant tube 5. At a front stage sucked to the compressor 1, the refrigerant is first heat exchanged with a capillary tube 3 to be heated in a heat exchanger 8, then again heated by an electric heater 8 wound on a suction refrigerant tube 5 of a heater, and then sucked to the compressor 1. According to the heating of the refrigerant at the suction side of the compressor 1 in this manner, the refrigerant can be cooled by the tube 3 on one hand to improve its cooling capability, and in the case of heating the refrigerant by the heater 9, power consumption of the heater 9 can be suppressed as much as possible, thereby saving the power.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a refrigeration circuit constituting a refrigeration cycle.

[0002]

2. Description of the Related Art Conventionally, JP-A-8-240349 (F25B 1/00) discloses a refrigeration cycle in which a compressor, a condenser, a capillary tube, and an evaporator are sequentially connected in a ring shape, and the compressor suction. There is disclosed a refrigerator provided with a liquid refrigerant heating means and a suction temperature detecting means provided in a pipe.

[0003] As the liquid refrigerant heating means, an electric heater is used.

[0004]

In the prior art described above, since the refrigerant in the suction pipe is heated only by the liquid refrigerant heating means, the power consumption of the liquid refrigerant heating means, that is, the electric heater is increased, and the power consumption is increased. Energy consumption.

The present invention has been made in view of the above problems, and provides a refrigeration circuit for minimizing energy consumption used for heating a suction refrigerant.

[0006]

According to a first aspect of the present invention, there is provided a refrigeration circuit in which a compressor, a condenser, a decompression device, and an evaporator are sequentially connected by refrigerant piping. A heat exchange unit that exchanges heat between the suction pipe, which is a refrigerant pipe connecting the evaporator and the compressor, and the decompression device, and a heating unit that further heats the refrigerant that has passed through the heat exchange unit. The provided refrigeration circuit is provided.

As described above, the heat exchange section exchanges heat with the pressure reducing device, and the heated refrigerant is further heated by the heating means.

Further, in the invention according to claim 2, the heating means is an electric heater, an oil cooler provided in the compressor, a discharge pipe of the compressor, or the condenser.
A refrigeration circuit as described.

Therefore, when the heating means is an electric heater,
It is possible to heat the suction pipe regardless of the heat exchange efficiency of the suction pipe and the pressure reducing device. When the heating means is an oil cooler, the suction pipe can be heated and the compressor can be cooled. Furthermore, when the heating means is a discharge pipe or a condenser of the compressor, the suction pipe can be heated,
Cooling of the discharge pipe or condenser can also be performed.

[0010] In the invention of claim 3, the refrigerant used in the refrigeration circuit has a specific heat ratio of 1.18 or less.
Alternatively, a refrigeration circuit according to claim 2 is provided.

Thus, a refrigerant having a specific heat ratio of 1.18 or less is used.

According to a fourth aspect of the present invention, there is provided a refrigerator provided with the refrigeration circuit according to any one of the first to third aspects.

[0013]

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

FIG. 1 is a refrigeration circuit diagram provided with an electric heater as a heating means, a refrigeration circuit diagram using an oil cooler of a compressor as a heating means, a refrigeration circuit diagram using a discharge pipe of a compressor as a heating means, and a heating means. FIG. 5 is a diagram showing a relationship between a heater input and a compressor input in the refrigeration circuit of FIG.

1 is a compressor such as a rotary compressor or a reciprocating compressor, 2 is a condenser for condensing the refrigerant discharged from the compressor 1, and 3 is a capillary as a decompression device for decompressing the refrigerant condensed in the condenser 2. The tubes 4 are evaporators for evaporating the refrigerant from the capillary tubes 3.

The compressor 1 and the evaporator 4 are connected by a suction refrigerant pipe 5, and the compressor 1 and the condenser 2 are connected by a discharge refrigerant pipe 6. The condenser 2 and the evaporator 4
Are connected by a connection refrigerant pipe 7 via a capillary tube 3.

Further, the suction refrigerant pipe 5 and the capillary tube 3 are provided in contact with each other in a heat exchange section 8 so as to be able to exchange heat.

In FIG. 1, reference numeral 9 denotes an example of a heating device. Specifically, an electric heater wound around the suction refrigerant pipe 5 and a power supply unit 10 for the electric heater 9 are shown.

As described above, the refrigerant in the gas-liquid mixed state evaporated and vaporized by the evaporator 4 is sucked into the compressor 1 through the suction refrigerant pipe 5, and the heat exchange section 8 makes the heat exchange with the capillary tube 3. After being exchanged and heated and further heated again by the electric heater 9, it is sucked into the compressor 1.

As described above, by exchanging heat between the capillary tube 3 and the suction refrigerant pipe 5 in the heat exchanging section 8, the refrigerant on the suction side of the compressor 1 can be heated and the capillary tube 3 can be heated. Refrigerant can be cooled.

Further, since the refrigerant once heated by the heat exchange in the heat exchange section 8 is heated by the electric heater 9, the power consumption of the electric heater 9 can be suppressed as low as possible.

The refrigerant used at this time preferably has a specific heat ratio (physical property value) of 1.18 or less.
There are a C (hydrochlorofluorocarbon) -based refrigerant (for example, HCFC22 or the like), an HFC (hydrofluorocarbon) -based refrigerant (for example, HFC134a or the like), and an HC (hydrocarbon) -based refrigerant (for example, isobutane, propane, or the like).

It should be noted that the specific heat ratio here is, strictly speaking, a state in a state of the suction refrigerant pipe 5 of the compressor 1 (a state of a suction gas).

FIG. 5 shows the relationship between the electric heater 9 and the input (W) of the compressor 1. The combination at this time is HCFC
22 and a rotary compressor, HFC134a and a rotary compressor, and HFC134a and a reciprocating compressor.

According to FIG. 5, in the combination of the HFC 134a and the rotary compressor, a remarkable decrease in compressor input is observed when the electric heater input is around 10W.

Further, in the combination of the HFC 134a and the reciprocating compressor, the compressor input is reduced when the electric heater input is between 8 and 12W.

As described above, when the refrigerant of the HFC 134a is used, the energy consumption of the compressor 1 can be reduced regardless of the type of the compressor 1.

In the case of the combination of the HCFC 22 and the rotary compressor, a remarkable reduction in the compressor input is not observed, but the heat exchange with the capillary tube 3 and the like can lower the condensation temperature of the discharge side refrigerant. It has energy saving effect.

In the embodiment shown in FIG. 2, an oil cooler 11 of the compressor 1 is provided in the suction refrigerant pipe 5. In this case, the refrigerant in a gas-liquid mixed state evaporated and vaporized in the evaporator 4 is:
After the heat exchange in the heat exchange section 8, the oil cooler 11
After performing heat exchange at, the refrigerant is sucked into the compressor 1.

Therefore, after the heat exchange in the heat exchange section 8 as described above, the compressor 1 is further cooled by the oil cooler 11 and the refrigerant on the suction side of the compressor 1 can be heated. It improves efficiency and has an energy-saving effect.

In the embodiment shown in FIG. 3, a second refrigerant pipe 5 and a second refrigerant pipe 6 are provided in contact with each other in heat exchange.
The heat exchange part 12 was formed. In this case, the refrigerant in the gas-liquid mixed state evaporated and vaporized in the evaporator 4 is heat-exchanged in the heat exchange unit 8, further heat-exchanged in the second heat exchange unit 12, and then sucked into the compressor 1. It is.

For this reason, after the heat exchange in the heat exchange section 8 as described above, the high-temperature gas refrigerant sent from the compressor 1 to the condenser 2 is further cooled in the second heat exchange section 12 and the compressor 1 Can heat the suction side refrigerant, thereby improving the heat exchange efficiency and achieving an energy saving effect.

In the embodiment shown in FIG. 4, the suction refrigerant pipe 5 and a part of the condenser 2, that is, the second condenser 13 are provided in heat exchange contact with each other. In this case, the refrigerant in a gas-liquid mixed state evaporated and vaporized in the evaporator 4 is subjected to heat exchange in the heat exchange section 8 and further to heat exchange with the second condenser 13 and then to the compressor 1
Sucked into.

For this reason, after the heat exchange in the heat exchange section 8 as described above, the high-temperature gas refrigerant can be further cooled in the second condenser 13 and the suction-side refrigerant of the compressor 1 can be heated. It improves the heat exchange efficiency and achieves an energy saving effect.

The refrigeration circuit as described above is used not only for home or commercial refrigerators, freezers or refrigerators, but also for showcases, vending machines and the like.

[0036]

As described in detail above, according to the present invention,
Since the suction pipe is heated by the decompression device and further heated by the heating means, the energy consumption of the heating means can be minimized. Furthermore, since the decompression device is also cooled by the suction pipe,
This will lower the condensation temperature of the refrigerant and improve the cooling capacity.
And, as the refrigerant, HCFC-based refrigerant, HFC-based refrigerant,
An HC-based refrigerant or the like having a specific heat ratio of 1.18 or less is used.

As described above, a refrigeration circuit capable of energy-saving operation can be provided. Furthermore, by using this refrigeration circuit in a refrigerator, the running cost of the refrigerator can be reduced, and an energy-saving refrigerator can be provided to customers.

According to the second aspect of the present invention, when the heating means is an electric heater, the suction pipe can be heated regardless of the heat exchange efficiency between the suction pipe and the pressure reducing device. When the heating means is an oil cooler, the suction pipe can be heated and the compressor can be cooled. Further, when the heating means is a discharge pipe or a condenser of the compressor, the suction pipe can be heated and the discharge pipe or the condenser can be cooled.

Accordingly, the operating efficiency of the compressor can be improved, and the condensation temperature of the compressor itself or the refrigerant on the compressor discharge side can be reduced, thereby achieving an energy saving effect.

[Brief description of the drawings]

FIG. 1 is a refrigeration circuit diagram provided with an electric heater as a heating means.

FIG. 2 is a refrigeration circuit diagram using an oil cooler of a compressor as a heating means.

FIG. 3 is a refrigeration circuit diagram using a discharge pipe of a compressor as a heating means.

FIG. 4 is a refrigeration circuit diagram using a condenser as a heating means.

FIG. 5 is a diagram showing a relationship between a heater input and a compressor input in the refrigeration circuit of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Condenser 3 Decompression device (capillary tube) 4 Evaporator 5 Suction pipe (suction refrigerant pipe) 6 Discharge pipe (discharge refrigerant pipe) 9 Heating device (electric heater) 11 Heating device (oil cooler) 12 Heating device ( (2nd heat exchange part) 13 heating device (second condenser)

Claims (4)

[Claims] 1. A refrigeration circuit in which a compressor, a condenser, a decompression device, and an evaporator are sequentially connected by a refrigerant pipe, wherein a suction pipe, which is a refrigerant pipe connecting the evaporator and the compressor, and the decompression device. A refrigeration circuit comprising: a heat exchange section for exchanging heat between the heat exchange section; and a heating means for further heating the refrigerant passing through the heat exchange section. 2. The refrigeration circuit according to claim 1, wherein the heating means is an electric heater, an oil cooler provided in the compressor, a discharge pipe of the compressor, or the condenser. 3. The refrigeration circuit according to claim 1, wherein the refrigerant used in the refrigeration circuit has a specific heat ratio of 1.18 or less. 4. A refrigerator provided with the refrigeration circuit according to claim 1.