JP5898569B2 - Radiant air conditioner - Google Patents

Description

  The present invention relates to a radiation type air conditioner.

  In a so-called separate type air conditioner, which is a heat pump type air conditioner for a house and divided into an outdoor unit and an indoor unit, the outdoor unit is provided with a heat exchanger and a fan, and the indoor unit also has a heat exchanger and a fan. It is a normal structure that is provided. On the other hand, even in the same separate type air conditioner, there is a type in which the indoor unit heat exchanger is configured as a radiant panel and the room is cooled or heated by heat radiation without using a fan. Exists. Examples thereof can be seen in Patent Documents 1 and 2.

  The air conditioner described in Patent Document 1 includes a radiation panel disposed on the ceiling of a building. Inside the radiation panel, refrigerant piping is arranged in a meandering manner. At the time of cooling operation, heat is absorbed by the radiant panel and radiant cooling is performed. During heating operation, heat is radiated from the radiant panel and radiant heating is performed. Radiant air conditioning is free from air agitation and noise from indoor fans, and can perform quiet and comfortable air conditioning.

  Patent Document 2 describes an air conditioner that performs cooling and heating using a plurality of radiation panels, such as arranging a radiation panel on a plurality of surfaces in a room, or installing a plurality of radiation panels even on one surface. Yes. In this air conditioner, a surface temperature detector is attached to the surface of each radiation panel, and the flow rate of the heat medium to each radiation panel is controlled according to the load of each radiation panel.

Japanese Patent Laid-Open No. 10-205802 JP-A-4-320752

  In controlling the radiant air conditioner, it is important to accurately measure the surface temperature of the radiant panel. An object of this invention is to enable it to cover both the cooling operation and the heating operation with the same temperature detector. Moreover, it aims at preventing the misdetection of the temperature detector by condensed water.

  A radiant air conditioner according to the present invention includes a radiant panel disposed indoors, an outdoor heat exchanger, and a compressor that circulates refrigerant through refrigerant piping through the radiant panel and the outdoor heat exchanger. The radiation panel has a heat dissipating part disposed in a housing, and a temperature detector for detecting the temperature of the refrigerant pipe is attached to an inner part of the refrigerant pipe connected to the heat dissipating part, and the air The controller of the harmony machine is characterized by performing control with reference to an output signal from the temperature detector.

  In the radiant air conditioner having the above configuration, the refrigerant pipe to which the temperature detector is attached is preferably a refrigerant pipe for liquid refrigerant.

  In the radiant air conditioner having the above-described configuration, it is preferable that the temperature detector is attached to a relatively upper portion in the casing portion of the refrigerant pipe.

  In the radiant air conditioner configured as described above, the refrigerant pipe to which the temperature detector is attached is a refrigerant pipe for liquid refrigerant, and the control unit detects the temperature detected by the temperature detector during cooling operation. It is preferable to refer to the surface temperature of the radiation panel, and to refer to the temperature obtained by adding the correction temperature to the temperature detected by the temperature detector during the heating operation as the surface temperature of the radiation panel.

  According to the present invention, the surface temperature of the radiation panel can be detected at the same position regardless of whether the refrigerant path of the radiant panel is the refrigerant path during the cooling operation or the refrigerant path during the heating operation. There is no need to change the control specifications for heating operation. Further, since the temperature detector is attached not to the surface of the radiant panel but to the refrigerant pipe, there is little risk that the condensed water will wet the temperature detector, and the possibility that the temperature detector erroneously detects can be reduced.

It is a schematic block diagram of the radiation type air conditioner which concerns on this invention, and shows the state at the time of air_conditionaing | cooling operation. It is a schematic block diagram of the radiation type air conditioner which concerns on this invention, and shows the state at the time of heating operation. It is a schematic block diagram which shows 1st Embodiment of a radiation panel. It is a schematic block diagram which shows 2nd Embodiment of a radiation panel. It is a schematic block diagram which shows 3rd Embodiment of a radiation panel. It is sectional drawing which shows 1st Embodiment of a thermal radiation part. It is sectional drawing which shows 2nd Embodiment of a thermal radiation part. It is a control block diagram of a radiation type air conditioner. It is a flowchart which shows operation | movement of a radiation type air conditioner. It is a table | surface which shows the relationship between compressor rotation speed and correction | amendment temperature. It is a graph which shows the relationship between compressor rotation speed and correction | amendment temperature.

  A schematic configuration of the radiant air conditioner 1 will be described with reference to FIG. The radiant air conditioner includes an outdoor unit 10 and a radiant panel 30. The radiation panel 30 is disposed indoors and corresponds to an indoor unit of a normal separate type air conditioner.

  The outdoor unit 10 houses a compressor 12, a four-way valve 13, an outdoor heat exchanger 14, an expansion valve 15, an outdoor blower 16, and the like in a housing 11 composed of sheet metal parts and synthetic resin parts. doing.

  The outdoor unit 10 is connected to the radiation panel 30 through two refrigerant pipes 17 and 18. The refrigerant pipe 17 is intended to flow a liquid refrigerant, and a pipe that is thinner than the refrigerant pipe 18 is used. Therefore, the refrigerant pipe 17 may be referred to as “liquid pipe”, “narrow pipe”, or the like. The refrigerant pipe 18 is intended to flow a gaseous refrigerant, and is thicker than the refrigerant pipe 17. Therefore, the refrigerant pipe 18 may be referred to as “gas pipe”, “thick pipe”, or the like. For example, HFC R410a or R32 is used as the refrigerant.

  In the refrigerant pipe inside the outdoor unit 10, a two-way valve 19 is provided in the refrigerant pipe connected to the refrigerant pipe 17, and a three-way valve 20 is provided in the refrigerant pipe connected to the refrigerant pipe 18. The two-way valve 19 and the three-way valve 20 are closed when the refrigerant pipes 17 and 18 are removed from the outdoor unit 10 to prevent the refrigerant from leaking from the outdoor unit 10 to the outside. When it is necessary to release the refrigerant from the outdoor unit 10 or from the entire refrigeration cycle including the radiation panel 30, the refrigerant is released through the three-way valve 20.

  The radiation panel 30 is often erected on the wall of the room, and a plurality of heat dissipating portions 32 are disposed inside a front-shaped rectangular casing 31 made up of sheet metal parts and synthetic resin parts. Although it was named “heat radiating part” for simplicity, this part not only radiates heat to the surrounding air during heating operation, but also absorbs heat from the surrounding air during cooling operation.

  The heat radiating part 32 is a cylindrical part and is arranged vertically. As shown in FIGS. 6 and 7, the basic configuration of the heat radiating section 32 is that the heat radiating fins 34 surround the central refrigerant pipe 33. The refrigerant pipe 33 and the heat radiating fins 34 are formed of a metal having good heat conductivity such as copper or aluminum and are in close contact with each other. The “vertical” referred to here is not limited to a strict vertical direction. The vertical direction including some inclination may be used.

  Both the heat dissipating fins 34 in FIG. 6 and the heat dissipating fins 34 in FIG. 7 have a horizontal cross-sectional shape in which a plurality of fins expand radially. 6 is formed as a part divided into two along the axial direction, and sandwiches the refrigerant tube 33 from the front and rear. The radiating fin 34 in FIG. 7 is a single component, and a refrigerant pipe 33 is inserted in a central portion corresponding to a wheel in terms of wheels. Needless to say, the structure of the heat dissipating part 32 shown in FIGS. 6 and 7 is merely an example, and heat dissipating fins 34 having different cross-sectional shapes can be used, or the refrigerant pipe 33 and the heat dissipating fins 34 can be combined in different ways. It is.

  A plurality (seven in the figure) of heat radiating portions 32 are arranged in the housing 31 so as to be parallel to each other. An opening 35 for exposing the heat radiating portion 32 is provided on the front surface of the housing 31. The plurality of heat radiation portions 32 are all connected to the refrigerant pipes 17 and 18. In the connection configuration example shown in FIG. 3, all the heat radiating portions 32 are connected in parallel to the refrigerant pipes 17 and 18. In the connection configuration example shown in FIG. 4, all the heat radiating sections 32 are connected in series to the refrigerant pipes 17 and 18.

  A system other than the system shown in FIGS. 3 and 4 may be employed to connect the plurality of heat radiation units 32. For example, it is possible to group a plurality of heat dissipating units 32 by a predetermined number, connect the heat dissipating units 32 belonging to the same group in parallel, and connect the groups in series. Alternatively, it is also possible to group a plurality of heat dissipating parts 32 by a predetermined number, connect the heat dissipating parts 32 belonging to the same group in series, and connect the groups in parallel.

  In order to control the operation of the radiant air conditioner 1, it is indispensable to know the temperature of each place. For this purpose, temperature detectors are arranged in the outdoor unit 10 and the radiation panel 30. In the outdoor unit 10, a temperature detector 21 is disposed in the outdoor heat exchanger 14, and a temperature detector 22 is disposed in the discharge pipe 12 a serving as the discharge unit of the compressor 12, and the suction serving as the suction unit of the compressor 12. A temperature detector 23 is disposed in the pipe 12 b, and a temperature detector 24 is disposed in the refrigerant pipe between the expansion valve 15 and the two-way valve 19. A temperature detector 36 is disposed on the radiation panel 30. Each of the temperature detectors 21, 22, 23, 24, and 36 is formed of a thermistor.

  The temperature detector 36 is intended to measure the temperature of the heat radiating section 32, but is not directly attached to the heat radiating section 32 but is attached to the refrigerant pipe 17 for liquid refrigerant as shown in FIG. The reason for arranging the temperature detector 36 in the refrigerant pipe 17 is as follows. That is, since the temperature of the heat radiating portion 32 varies depending on the position (particularly the upper and lower positions), it is difficult to determine at which position the temperature detector 36 is disposed.

  The surface temperature of the heat radiating portion 32 also depends on how the refrigerant path connecting the plurality of heat radiating portions 32 is designed. When the refrigerant path is a single path, a temperature difference is likely to occur due to a pressure loss or a gas-liquid phase change of the refrigerant. When there are a plurality of refrigerant paths, a temperature difference may occur depending on the path. Some temperature detectors are covered with metal to improve temperature sensitivity. When the metal constituting the heat radiating portion 32 and the metal used in the temperature detector are different, a potential difference due to a different metal is generated at the contact portion, and there is a possibility of causing electric corrosion. In any case, it is not easy to determine at which position of the heat radiation part 32 the temperature detector 36 is arranged.

  If the refrigerant pipe 17 inside the casing 31 is used as the attachment location of the temperature detector 36, the above problem is solved. The refrigerant pipe 17 is a location where the refrigerant throttled by the expansion valve 15 flows in during the cooling operation, and a location where the condensed refrigerant flows out from the heat radiating unit 32 during the heating operation.

  Since the refrigerant in the gas-liquid two-phase state (however, the vaporization has not progressed so much and the liquid-phase refrigerant is abundant) flows through the refrigerant pipe 17 during the cooling operation, in other words, since the gas-liquid phase change of the refrigerant is small, the refrigerant The temperature of the pipe 17 can be handled as the temperature of the heat radiation part 32. On the other hand, during the heating operation, the refrigerant pipe 17 becomes a supercooling part (liquid phase part) of the refrigeration cycle, and liquid refrigerant accumulates, so that the temperature of the refrigerant pipe 17 cannot be immediately handled as the temperature of the heat radiating part 32. However, the surface temperature of the heat radiating section 32 can be obtained from the measured temperature of the temperature detector 36 even during the heating operation based on the concept of “correction temperature” described later.

  The attachment position of the temperature detector 36 is a relatively higher portion of the refrigerant pipe 17 in the casing 31. The reason why such a place is selected as the mounting position of the temperature detector 36 will be described later.

The control unit 40 shown in FIG. 8 controls the overall control of the radiant air conditioner 1. The control unit 40 performs control so that the room temperature reaches a target value set by the user.

  The control unit 40 issues an operation command to the compressor 12, the four-way valve 13, the expansion valve 15, and the outdoor blower 16. The control unit 40 receives output signals of the detected temperatures from the temperature detectors 21 to 24 and the temperature detector 36. While referring to the output signals from the temperature detectors 21 to 24 and the temperature detector 36, the control unit 40 issues an operation command to the compressor 12 and the outdoor fan 16, and to the four-way valve 13 and the expansion valve 15. Issue a status switch command.

  FIG. 1 shows a state in which the radiant air conditioner 1 is performing a cooling operation (dehumidifying operation) or a defrosting operation. The high-temperature and high-pressure refrigerant discharged from the compressor 12 enters the outdoor heat exchanger 14 where heat exchange with outdoor air is performed. That is, the refrigerant dissipates heat to the outdoor air. The refrigerant that has dissipated heat and is condensed to be liquid is sent from the outdoor heat exchanger 14 to the heat dissipating part of the radiation panel 30 through the expansion valve 15, decompressed and expanded to a low temperature and low pressure, and the surface temperature of the heat dissipating part 32 is lowered. . The heat dissipating part 32 whose surface temperature has dropped absorbs heat from the room air, thereby cooling the room air. After the heat absorption, the low-temperature gaseous refrigerant returns to the compressor 12. The airflow generated by the outdoor fan 16 promotes heat dissipation from the outdoor heat exchanger 14.

  FIG. 2 shows a state where the radiant air conditioner 1 is performing a heating operation. At this time, the four-way valve 13 is switched, and the refrigerant flow is reversed from that during the cooling operation. That is, the high-temperature and high-pressure refrigerant discharged from the compressor 12 enters the heat radiating section 32 where heat exchange with room air is performed. That is, the refrigerant dissipates heat to the room air, and the room air is warmed. The refrigerant that has dissipated heat and is condensed to become liquid is sent from the heat dissipating section 32 to the outdoor heat exchanger 14 through the expansion valve 15, and is decompressed and expanded to lower the surface temperature of the outdoor heat exchanger 14. The outdoor heat exchanger 14 whose surface temperature has dropped absorbs heat from outdoor air. After the heat absorption, the low-temperature gaseous refrigerant returns to the compressor 12. The airflow generated by the outdoor fan 16 promotes heat absorption by the outdoor heat exchanger 14. Frost adhering to the outdoor heat exchanger 14 due to heat absorption is removed by performing a defrosting operation.

  FIG. 9 shows a flowchart when the radiation type air conditioner 1 is operated. FIG. 9 shows a flowchart during heating operation.

  When the heating operation is started, temperature detection is performed in step # 101. The temperature detection in this case is temperature detection by the temperature detector 36. As described above, the temperature detector 36 is disposed in the refrigerant pipe 17 and does not directly detect the surface temperature of the radiation panel 30 (more precisely, the surface temperature of the heat radiating unit 32). Further, the difference between the temperature of the refrigerant pipe 17 and the surface temperature of the radiation panel 30 varies depending on what value the degree of supercooling is. Therefore, during the heating operation, the surface temperature of the radiation panel 30 is predicted by correcting the temperature by predicting the degree of supercooling of the heat radiating unit 32 from the temperature of the refrigerant pipe 17. Specifically, in step # 102, temperature correction is performed by adding the correction temperature shown in the table of FIG. 10 to the temperature detected by the temperature detector 36.

  In the table of FIG. 10, the rotation speed of the compressor 12 is taken as a parameter. When the rotation speed is 1,000 rpm, the correction temperature is 6 ° C., and when the rotation speed is 2,000 rpm, the correction temperature is 6 ° C. and the rotation speed is 3,000 rpm. The correction temperature is 8 ° C., the rotation speed is 4,000 rpm, the correction temperature is 10 ° C., the rotation speed is 5,000 rpm, the correction temperature is 12 ° C., and the rotation speed is 6,000 rpm, the correction temperature is 14 ° C. The correction temperature is 14 ° C. when the rotation speed is 7,000 rpm. FIG. 11 is a graph showing the relationship between the rotation speed of the compressor 12 and the correction temperature.

  The correction temperature shown in FIGS. 10 and 11 is merely an example, and it goes without saying that the value of the correction temperature changes depending on various conditions such as the size of the radiation panel 30 and the capacity of the compressor 12. It is preferable to determine the correction temperature through repeated experiments.

  As described above, the control unit 40 controls the heating operation of the radiant air conditioner 1 while referring to the surface temperature of the radiant panel 30 obtained by correcting the temperature detected by the temperature detector 36.

  In step # 103, the control unit 40 checks whether or not the radiation panel 30 has reached a temperature higher than the set temperature. The temperature detector 36 can also be used for temperature detection in this case. When the radiation panel 30 reaches a temperature equal to or higher than the set temperature, the process proceeds to step # 104, and the control unit 40 performs control to prevent the radiation panel 30 from overheating. If the radiant panel 30 does not reach a higher temperature than the set temperature, the control unit 40 continues the heating operation at that time. As control for preventing overheating of the radiation panel 30, for example, control such as lowering the rotational speed of the compressor 12, increasing (opening) the opening degree of the expansion valve 15, or lowering the rotational speed of the outdoor blower 16 is considered. It is done.

  As described above, by using the temperature detector 36 to check whether or not the radiation panel 30 has reached a temperature higher than the set temperature, that is, the temperature detector 36 for air conditioning control is also used as a temperature detector for protection. By doing so, the control system of the radiation type air conditioner 1 can be simplified.

  In the case of cooling operation (dehumidifying operation) or defrosting operation, the temperature detected by the temperature detector 36 can be handled as the surface temperature of the heat radiating unit 32. For this reason, temperature correction as in the case of heating operation is not necessary.

  As described above, since the temperature detector 36 is attached to the inside of the casing 31 of the refrigerant pipe 17, whether the refrigerant path of the radiation panel 30 is the refrigerant path during the cooling operation or the refrigerant path during the heating operation. Regardless of, the surface temperature of the radiation panel 30 can be detected at the same position. For this reason, it is not necessary to change the control specifications between the cooling operation and the heating operation.

  During the cooling operation (dehumidifying operation), condensed water is generated in the heat radiating unit 32. Since the temperature detector 36 is attached to a relatively upper part of the refrigerant pipe 17 in the casing 31, even if the condensed water in the heat radiating portion 32 is accumulated as drain water below the heat radiating portion 32 (drain water). Is received by a drain pan (not shown) disposed below the heat dissipating part 32), and is not in contact with drain water. For this reason, there is no need to worry that an error occurs in the temperature detected by the temperature detector 36 or that the temperature detector 36 fails. Although not as much as the heat radiating section 32, condensed water is also generated in the refrigerant pipe 17. However, in order to reduce the influence of the condensed water, it is meaningful to arrange the temperature detector 36 in the upper part of the refrigerant pipe 17. . In FIG. 1, a temperature detector 36 is provided in the refrigerant pipe 17 that passes through the upper frame of the casing 31 above the heat radiating section 32.

  Even in the case where a plurality of heat radiation parts 32 are connected in series as shown in FIG. 4, the temperature detection part 36 is arranged in the upper part of the refrigerant pipe 17. Further, when a plurality of heat radiating portions 32 are connected in series, as shown in FIG. 5, the temperature detector 36 can be attached to the refrigerant pipe 37 that connects the heat radiating portions 32 to each other at the upper part of the radiation panel 30. Even with this configuration, the temperature detector 36 can be protected from condensed water. In short, the fact that the temperature detector 36 is arranged at a place where the condensed water hardly occurs is a matter to be protected.

  Up to now, the heat radiation part 32 has been described as being arranged vertically, but a structure in which the heat radiation part 32 is arranged horizontally is also possible. In this case, the heat dissipating fins 34 may be configured by arranging a large number of thin plates perpendicular to the axis of the refrigerant pipe 33 with a space therebetween.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  The present invention is widely applicable to a radiant air conditioner.

DESCRIPTION OF SYMBOLS 1 Radiation-type air conditioner 10 Outdoor unit 11 Case 12 Compressor 13 Four-way valve 14 Outdoor heat exchanger 15 Expansion valve 16 Outdoor blower 17, 18 Refrigerant piping 30 Radiation panel 31 Case 32 Heat radiation part 36 Temperature detector 40 Control unit

Claims (3)

In a radiant air conditioner comprising a radiant panel disposed indoors, an outdoor heat exchanger, and a compressor that circulates refrigerant through refrigerant piping through the radiant panel and the outdoor heat exchanger,
The radiation panel has a heat dissipating part disposed in a housing,
A temperature detector that detects the temperature of the refrigerant pipe is attached to the inside part of the casing of the refrigerant pipe connected to the heat radiating section,
Control unit of the air conditioner have reference lines to control the output signal from the temperature detector, cooling operation by referring to the temperature of the temperature detector detects as the surface temperature of the radiant panels, heating operation The radiation air conditioner is characterized in that a temperature obtained by adding a correction temperature corresponding to the rotation speed of the compressor to the temperature detected by the temperature detector is referred to as the surface temperature of the radiation panel .   The radiant air conditioner according to claim 1, wherein the refrigerant pipe to which the temperature detector is attached is a refrigerant pipe for liquid refrigerant. The radiant air conditioner according to claim 1 or 2, wherein the temperature detector is attached to a relatively upper portion of the refrigerant pipe in the casing .

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