JP5912866B2 - Refrigerated / refrigerated showcase - Google Patents

Description

  The present invention relates to a frozen / refrigerated showcase used for cooling and selling frozen foods, refrigerated foods, and fresh foods at supermarkets, convenience stores, and the like.

  Conventionally, in supermarkets and convenience stores, frozen and refrigerated showcases are used to cool and sell frozen foods, refrigerated foods, and fresh foods (see, for example, Patent Document 1 below). Such a refrigeration / refrigeration showcase includes a compressor for compressing refrigerant, a condenser for condensing the compressed refrigerant, an expansion valve for decompressing the condensed liquid refrigerant, a cooler for vaporizing the decompressed refrigerant, A refrigerant that includes an accumulator or the like that separates the liquid refrigerant when the refrigerant that has passed through the cooler flows in and the liquid refrigerant is contained in the refrigerant that has flowed in is provided. In this refrigeration apparatus, the size of the cooler and the amount of refrigerant flowing into the cooler are set so that almost all of the refrigerant is vaporized in the cooler while the refrigeration apparatus is in operation.

Japanese Patent Laid-Open No. 05-60449

  However, in such a refrigeration / refrigeration showcase, the operation of the refrigeration apparatus may be stopped during defrosting of the cooler or temperature adjustment in the showcase. When the operation of the refrigeration apparatus is stopped, the liquid refrigerant may stay in the cooler, and the cooler is arranged above the accumulator, so the liquid refrigerant stayed in the cooler. Will flow down into the accumulator.

  When the liquid refrigerant staying in the cooler flows down into the accumulator and restarts the refrigeration system from a state where a large amount of liquid refrigerant exists in the accumulator, the liquid refrigerant is sufficiently separated in the accumulator. In some cases, liquid refrigerant may flow from the accumulator into the compressor. When the liquid refrigerant flows into the compressor, liquid compression occurs in the compressor, and the compressor may be damaged by the liquid compression.

  The present invention has been made in view of such points, and its purpose is to prevent the liquid refrigerant staying in the cooler from flowing down into the accumulator when the operation of the refrigeration apparatus is stopped. When OLE_LINK1OLE_LINK2 resumes operation of the refrigeration system Prevents liquid refrigerant in the accumulator from flowing into the compressor to OLE_LINK1OLE_LINK2, preventing liquid compression from occurring in the compressor and damage to the compressor due to liquid compression In addition, when the operation of the refrigeration system is resumed, the temperature of the refrigerant is quickly detected to quickly adjust the opening of the expansion valve. An object of the present invention is to provide a freezing / refrigerating showcase capable of preventing the refrigerant from flowing out of the cooler.

The refrigeration / refrigeration showcase according to the present invention includes a storage chamber having an open front surface, and a duct through which cool air flows to form an air curtain that houses a cooler and a blower fan and covers the front surface of the storage chamber. A case main body, and a base portion that is provided at a lower portion of the case main body and that accommodates an accumulator, a compressor, and a condenser connected to the cooler, and is provided in the cooler at the inlet side of the cooler. In a refrigeration / refrigeration showcase provided with an expansion valve for adjusting the amount of refrigerant flowing in, the operation of the compressor is stopped at the outlet pipe of the cooler that guides the refrigerant flowing out of the cooler into the accumulator. rising of said a position higher than the level of the liquid refrigerant staying in the condenser rises to a height position following the position of the inlet side pipe of the refrigerant flowing into the cooler when And provided with an expansion valve temperature sensing cylinder for detecting the temperature of the refrigerant in order to adjust the opening degree of the expansion valve on the upstream side of the uppermost position of the rising part along the refrigerant flow direction. It is characterized by.

  Further, in the above-described freezing / refrigerating showcase according to the present invention, it is desirable that the expansion valve temperature sensing cylinder is attached to an upper position of the rising portion.

  According to the refrigeration / refrigeration showcase according to the present invention, a riser is provided in the outlet side pipe of the cooler, and this riser is in a liquid state that stays in the cooler when the operation of the compressor is stopped. Since the refrigerant has risen to a position higher than the coolant level of the refrigerant, even if the liquid refrigerant stays in the cooler when the compressor is stopped, the accumulated liquid refrigerant will flow down into the accumulator. When the operation of the compressor is resumed, the liquid refrigerant that has flowed down into the accumulator can be prevented from flowing into the compressor without being separated by the accumulator. It is possible to prevent the compressor from being damaged due to the occurrence of the liquid or the liquid compression.

  In addition, according to the present invention, even when the cooler is designed to be large, it is possible to prevent the liquid refrigerant that has accumulated from flowing into the accumulator, so that a freezer / refrigerator showcase with high cooling performance can be provided by increasing the size of the cooler. It becomes possible to do.

  Furthermore, by attaching an expansion valve temperature sensing cylinder upstream from the uppermost position of the riser along the refrigerant flow direction, the refrigerant temperature in the cooler can be detected quickly when the compressor is restarted. Thus, the opening degree of the expansion valve can be adjusted quickly, and the outflow of the liquid refrigerant from the cooler caused by the delay in adjusting the opening degree of the expansion valve can be prevented.

  Further, since it is possible to prevent the liquid refrigerant staying in the cooler from flowing down into the accumulator, the accumulator can be designed to be smaller than the conventional one, and the cost can be reduced.

  In addition, since the rising height position of the rising portion is equal to or lower than the height position of the inlet side piping of the refrigerant flowing into the cooler, the installation space for the outlet side piping is provided even if the rising portion is provided in the outlet side piping. Can be suppressed.

  In addition, an expansion valve temperature sensing cylinder for detecting the temperature of the refrigerant flowing out of the cooler is attached to the upper portion of the rising portion, and the temperature of the refrigerant in the rising portion becomes higher at the upper portion. The temperature of the refrigerant detected by the cylinder rises, and the opening of the expansion valve whose opening is adjusted according to the detection result of the expansion valve temperature sensing cylinder can be increased, and by increasing the opening of the expansion valve The amount of refrigerant flowing into the cooler can be increased. The amount of refrigerant flowing into the cooler can be increased to increase the heat exchange efficiency of the cooler, and the heat exchanger efficiency of the cooler can be increased to control the temperature in the storage chamber. You can increase the time to stop. By increasing the time for stopping the operation of the compressor, it is possible to reduce power consumption.

It is a section side view showing the freezing and refrigeration showcase of one embodiment of the present invention. It is a block diagram which shows the structure of a freezing apparatus. It is a front view which shows the structure of a cooler. It is a side view which shows the structure of a cooler. It is sectional drawing which shows the attachment structure of the expansion valve temperature sensing cylinder to a starting part. It is explanatory drawing which simplifies and shows the piping structure of the heat exchanger tube of a cooler, or discharge side piping.

  An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the refrigerated / refrigerated showcase 1 includes a case main body 3 constituted by a heat insulating wall 2 and a base portion 4 provided at a lower portion of the case main body 3.

  The case body 3 is formed with a storage chamber 5 and a duct 6.

  The storage room 5 is a space having an open front surface, and a plurality of product display shelves 7 arranged in the vertical direction in the interior thereof, and a floor deck unit 8 positioned below the lowermost product display shelf 7. Is provided. The merchandise to be sold is displayed on the merchandise display shelves 7 and the floor deck section 8.

  The duct 6 is a passage formed inside the heat insulating wall 2 so as to surround the storage chamber 5, and in this duct 6, a cooler 9, a blower fan 10, an expansion valve 11, and a refrigerating apparatus which will be described later. Is housed. The blower fan 10 blows air in the duct 6 toward the cooler 9 and causes the air cooled by hitting the cooler 9 (hereinafter referred to as “cold air”) to flow in the direction indicated by the arrow in the duct 6. It is configured as follows. An air outlet 12 through which cool air flowing through the duct 6 blows out is formed on the upper side of the duct 6, and an air inlet 13 through which the cold air blown from the air outlet 12 is sucked is formed at the lower part of the duct 6. The cool air that is blown out from the air outlet 12 and sucked into the air inlet 13 forms an air curtain that covers the front surface of the storage chamber 5.

  The base unit 4 accommodates a compressor 14, a condenser 15, an accumulator 16, and a blower fan 17 that constitute a refrigeration apparatus described later together with the cooler 9, the blower fan 10, and the expansion valve 11 described above. .

  Based on FIG. 2, the structure of the freezing apparatus 18 is demonstrated. The refrigeration apparatus 18 is configured by connecting the compressor 14, the condenser 15, the expansion valve 11, the cooler 9, and the accumulator 16 with a pipe through which refrigerant flows in this order. Further, the blower fan 10 is disposed at a position where air is blown toward the cooler 9, and the blower fan 17 is disposed at a position where air is blown toward the condenser 15.

  The compressor 14 is configured to compress a gaseous refrigerant, and the condenser 15 is configured to condense and liquefy the refrigerant compressed by the compressor 14. The expansion valve 11 is configured to depressurize the refrigerant liquefied by the condenser 15 and to flow the depressurized refrigerant into the cooler 9. The expansion valve 11 is provided so that the opening degree can be adjusted, and is configured to adjust the amount of the refrigerant flowing into the cooler 9 by adjusting the opening degree. As will be described later, the cooler 9 has fins and heat transfer tubes, and is configured to vaporize the inflowing refrigerant. The accumulator 16 separates the liquid refrigerant when the refrigerant that has flowed out of the cooler 9 is introduced and contains the liquid refrigerant in the refrigerant that has flowed in, and removes only the gaseous refrigerant from the compressor 14. It is comprised so that it may flow in. The arrows shown in FIG. 2 indicate the flow direction of the refrigerant in the refrigeration apparatus 18.

  As shown in FIGS. 3 and 4, the cooler 9 includes a plurality of plate-like fins 19 arranged in parallel at a predetermined pitch, and a heat transfer tube 20 that passes through the fins 19 and is piped in a zigzag manner. The refrigerant flows through the heat transfer tube 20. The fin 19 and the heat transfer tube 20 are formed of a metal having high thermal conductivity, for example, aluminum or copper.

  One end side of the heat transfer tube 20 is connected to an inlet side pipe 21 through which the refrigerant decompressed by the expansion valve 11 flows into the cooler 9. The connection portion between the inlet side pipe 21 and the heat transfer tube 20 is the upper side of the side surface of the cooler 9.

  Connected to the other end of the heat transfer tube 20 is an outlet side pipe 22 through which the refrigerant that has passed through the cooler 9 flows out of the cooler 9 and guides the discharged refrigerant to the accumulator 16. The connection point between the heat transfer tube 20 and the outlet side pipe 22 is the lower side of the side surface of the cooler 9.

  The outlet side pipe 22 is formed with an inverted U-shaped rising portion 23 that rises upward along the side surface of the cooler 9 and is bent downward from the rising uppermost position. The rising height of the rising portion 23 is higher than the water level of the liquid refrigerant that stays in the cooler 9 when the operation of the refrigeration apparatus 18 is stopped (synonymous with the case where the operation of the compressor 14 is stopped). It is considered as a position. Furthermore, the rising height position of the rising portion 23 is set to be equal to or lower than the height position of the inlet side pipe 21 into which the refrigerant flows into the cooler 9. The arrows shown in FIGS. 3 and 4 indicate the flow direction of the refrigerant flowing into the cooler 9 and the flow direction of the refrigerant flowing out of the cooler 9.

  As shown in FIGS. 3 and 4, an expansion valve temperature sensing cylinder 24 is attached to the rising portion 23. The expansion valve temperature sensing cylinder 24 is attached to the riser 23 by using a copper band 25 so that the outer peripheral surface of the riser 23 and the outer peripheral surface of the expansion valve temperature sensing cylinder 24 are brought into close contact with each other. The expansion valve temperature sensing cylinder 24 is configured to detect the temperature of the refrigerant flowing in the riser 23, and the opening degree of the expansion valve 11 is adjusted based on the detection result of the expansion valve temperature sensing cylinder 24. .

  The relationship between the detection result of the refrigerant temperature by the expansion valve temperature sensing cylinder 24 and the opening degree of the expansion valve 11 adjusted based on the detection result is set as follows. When the temperature of the refrigerant detected by the expansion valve temperature sensing cylinder 24 is low, it is considered that the liquid refrigerant that cannot be completely vaporized in the cooler 9 flows in the start-up unit 23. The opening degree of the expansion valve 11 is adjusted so as to reduce the amount of refrigerant flowing into the interior. On the other hand, when the temperature of the refrigerant detected by the expansion valve temperature sensing cylinder 24 is high, only the gaseous refrigerant flows through the start-up portion 23, and there is a margin in the ability to vaporize the refrigerant in the cooler 9. The opening degree of the expansion valve 11 is adjusted so as to increase the amount of refrigerant flowing into the cooler 9.

  FIG. 5 is a cross-sectional view showing a structure for attaching the expansion valve temperature sensing cylinder 24 to the rising portion 23. A copper band 25 is wound around the rising portion 23 and the expansion valve temperature sensing cylinder 24 with their outer peripheral surfaces in close contact with each other. The band 25 is tightened by a screw 26, and the tight state between the rising portion 23 and the expansion valve temperature sensing cylinder 24 is maintained by the tightening.

  FIG. 6 is an explanatory diagram showing the piping structure of the cooler 9 in a simplified manner. An inlet side pipe 21 is connected to one end side of the heat transfer tube 20 located on the upper side of the cooler 9, and an outlet side pipe 22 is connected to the other end side of the heat transfer tube 20 located on the lower side of the cooler 9. A rising portion 23 is formed in the side pipe 22. An expansion valve temperature sensing cylinder 24 is attached to the riser 23 by a band 25, and the installation position of the expansion valve temperature sensing cylinder 24 to the riser 23 is at the riser 23 along the refrigerant flow direction. The upper position of the upright portion 23 is upstream of the uppermost position.

  FIG. 6 shows a case where the operation of the refrigeration apparatus 18 is stopped, and a liquid refrigerant L stays in the heat transfer tube 20 together with the gaseous refrigerant G.

  In such a configuration, during operation of the refrigeration apparatus 18, as indicated by the arrows in FIG. 2, the refrigerant circulates in the refrigeration apparatus 18, the gaseous refrigerant is compressed by the compressor 14, and the compressed refrigerant is The refrigerant condensed and liquefied by the condenser 15 is decompressed by the expansion valve 11, the refrigerant decompressed by the expansion valve 11 flows into the cooler 9, is vaporized, and is vaporized in the cooler 9. Returns to the compressor 14 via the accumulator 16.

  And by blowing with the ventilation fan 10 toward the cooler 9 accommodated in the duct 6, the air in the duct 6 is cooled by the cooler 9 to become cold air, and this cold air is a slit formed in the duct 6. The inside of the storage chamber 5 is cooled by being guided into the storage chamber 5 from the gap portion. Further, the cool air in the duct 6 flows in the duct 6 as shown by the arrow in FIG. 1, and the air curtain covering the front surface of the storage chamber 5 is formed by sucking the cool air blown from the air outlet 12 from the air inlet 13. And the cooling performance in the store room 5 becomes high by forming this air curtain.

  In the refrigeration / refrigeration showcase 1, the operation of the refrigeration apparatus 18 is stopped when defrosting the frost adhering to the cooler 9 or when the temperature in the storage chamber 5 reaches a set temperature. When the operation of the refrigeration apparatus 18 is stopped, the liquid refrigerant L may stay in the heat transfer tube 20 of the cooler 9 as shown in FIG.

  In the refrigeration / refrigeration showcase 1 of the present embodiment, a rising portion 23 is formed in the outlet side pipe 22 of the cooler 9 that connects the cooler 9 and the accumulator 16, and the rising height of the rising portion 23 is When the operation of the refrigeration apparatus 18 is stopped, the position is higher than the water level of the liquid refrigerant that stays in the cooler 9. For this reason, even if the liquid refrigerant stays in the cooler 9 when the operation of the refrigeration apparatus 18 is stopped, the liquid refrigerant can be prevented from flowing down to the accumulator 16. Therefore, when the operation of the refrigeration apparatus 18 is resumed, a situation where a large amount of liquid refrigerant exists in the accumulator 16 does not occur, and a large amount of liquid refrigerant exists in the accumulator 16. It is possible to prevent the liquid refrigerant from being sufficiently separated and the liquid refrigerant from flowing into the compressor 14. For this reason, generation | occurrence | production of the liquid compression in the compressor 14 can be prevented, and the failure | damage of the compressor 14 resulting from liquid compression can be prevented.

  Further, by providing the start-up unit 23, it is possible to prevent the liquid refrigerant from flowing into the accumulator 16 when the operation of the refrigeration apparatus 18 is stopped. Therefore, the accumulator 16 can be designed to be small, and the accumulator 16 can be downsized. By doing so, the cost can be reduced.

  Further, the amount of the liquid refrigerant that stays in the cooler 9 when the operation of the refrigeration apparatus 18 is stopped increases as the cooler 9 increases in size, and increases as the load of the refrigerant flowing into the cooler 9 decreases. . However, in the refrigeration / refrigeration showcase 1 of the present embodiment, the size of the cooler 9 is increased and the load of the refrigerant flowing into the cooler 9 is reduced to reduce the liquid state that remains in the cooler 9 when the operation is stopped. Even if the amount of the refrigerant increases, the rising portion 23 is provided so that the liquid refrigerant flows down into the accumulator 16, or the liquid refrigerant enters the compressor 14 when the operation is resumed. Inflow can be prevented. Therefore, the cooling performance of the cooler 9 is improved by increasing the size of the cooler 9 or reducing the load of the refrigerant flowing into the cooler 9 to increase the amount of refrigerant flowing into the cooler 9. The cooling performance can be sufficiently exhibited even at high temperatures in summer.

  Further, the rising portion 23 has a rising height position equal to or lower than the height position of the inlet side pipe 21 of the refrigerant flowing into the cooler 9, so the rising portion 23 is provided on the outlet side pipe 22. Also, an increase in installation space for the outlet side pipe 22 can be suppressed. Thereby, it is possible to prevent the size of the main body portion of the cooler 9 composed of the heat transfer tubes 20 and the fins 19 from being restricted in spite of the provision of the start-up portion 23. In addition, the cooling performance can be maintained.

  An expansion valve temperature sensing cylinder 24 that detects the temperature of the refrigerant flowing out of the cooler 9 and adjusts the opening degree of the expansion valve 11 based on the detection result is attached to an upper position of the rising portion 23. . The refrigerant in the start-up unit 23 is vaporized and becomes higher as it goes upward. For this reason, the temperature of the refrigerant detected by the expansion valve temperature sensing cylinder 24 is increased by attaching the expansion valve temperature sensing cylinder 24 to the upper position of the riser 23, and the temperature detected by the expansion valve temperature sensing cylinder 24 is increased. As the height increases, the opening of the expansion valve 11 increases and the amount of refrigerant flowing into the cooler 9 increases, so that the heat exchange efficiency of the cooler 9 can be increased. As the heat exchange efficiency of the cooler 9 increases, the time for stopping the operation of the refrigeration apparatus 18 for adjusting the temperature in the storage chamber 5 can be lengthened, and the power consumption can be reduced accordingly.

  As mentioned above, although one embodiment of the present invention has been described, this embodiment has been presented as an example, and is not intended to limit the scope of the invention, and various modifications can be made without departing from the spirit of the invention. Can be omitted, replaced, or changed.

DESCRIPTION OF SYMBOLS 1 Refrigeration / refrigeration showcase 2 Heat insulation wall 3 Case main body 4 Base part 5 Storage room 6 Duct 7 Merchandise display shelf 8 Floor deck part 9 Cooler 10 Blower fan 11 Expansion valve 12 Outlet 13 Inlet 14 Compressor 15 Condenser 16 Accumulator 17 Blower fan 18 Refrigeration device 19 Fin 20 Heat transfer tube 21 Inlet side piping 22 Outlet side piping 23 Rising portion 24 Expansion valve temperature sensing cylinder 25 Band 26 Screw G Gaseous refrigerant L Liquid refrigerant

Claims (2)

A case body having a storage chamber having an open front surface, a cooler and a blower fan therein, and a duct through which cool air forms an air curtain covering the front surface of the storage chamber; and a lower portion of the case body An expansion valve that adjusts the amount of refrigerant flowing into the cooler on the inlet side of the cooler, and includes a base portion that houses an accumulator, a compressor, and a condenser connected to the cooler. In the freezer / refrigerated showcase provided,
Wherein the refrigerant flowing from the cooler to the outlet pipe of the cooler for guiding in said accumulator, met position higher than the level of the liquid refrigerant staying in the case of stopping the operation of the compressor to the cooler Providing a rising portion that rises to a position below the height position of the inlet side piping of the refrigerant flowing into the cooler, upstream of the uppermost position of the rising portion along the refrigerant flow direction, A freezing and refrigeration showcase comprising an expansion valve temperature sensing cylinder for detecting the temperature of the refrigerant in order to adjust the opening of the expansion valve. 2. The refrigeration / refrigeration showcase according to claim 1, wherein the expansion valve temperature sensing cylinder is attached to an upper position of the rising portion .

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