JP5989260B2 - Outdoor unit - Google Patents

Description

  The present invention relates to an outdoor unit.

  For example, when the air conditioner is configured by a heat pump system, a refrigerant circuit is configured and a refrigeration cycle is formed. In the refrigerant circuit, for example, an outdoor unit including a compressor and an outdoor unit side heat exchanger, an indoor unit including an expansion valve, and an indoor unit side heat exchanger are connected by a refrigerant pipe. That is, the refrigerant circuit has a configuration in which an outdoor unit that is a heat source side unit and an indoor unit that is a load side unit are connected by a refrigerant pipe, and the refrigerant circulates.

  The refrigerant circuit is, for example, an indoor unit-side heat exchanger, and evaporates the refrigerant by absorbing heat from the air in the air-conditioning target space that is a heat exchange target. The refrigerant circuit condenses the refrigerant by radiating heat to the air in the air-conditioning target space, which is a heat exchange target, for example, with an indoor heat exchanger. That is, the air conditioner harmonizes the air in the air-conditioning target space by changing the pressure and temperature of the refrigerant flowing through the refrigerant circuit.

  Here, the outdoor unit is surrounded by a casing, and the outdoor unit side heat exchanger is accommodated in the casing, and an outdoor unit base is provided at the lower part of the outdoor unit side heat exchanger. It has been. The outdoor unit base part has an outdoor unit side heat exchanger mounted thereon. The outdoor unit base is provided with a drain hole.

  The drain hole discharges drain water or the like generated in the defrosting operation or the like out of the housing. For example, when the air conditioner performs a heating operation, the outdoor unit-side heat exchanger functions as an evaporator. Therefore, if the heating operation is performed when the outside air temperature is low, the drain water or the like staying in the outdoor unit base is frozen and the drain hole is closed. If the drain hole is closed, drain water or the like is not discharged from the outdoor unit base part, and stays in the outdoor unit base part, so that icing further proceeds. As a result, root ice and the like are caused. Since root ice obstructs the flow of air passing through the outdoor unit-side heat exchanger, efficient heat exchange is not performed.

  Thus, as one of the prior arts, there has been an air conditioner in which an electric heater is installed around the drain hole. The electric heater is heated by energization and melts ice in the outdoor unit base. That is, among conventional air conditioners, there is one that prevents icing of water remaining in the outdoor unit base by energizing an electric heater (see, for example, Patent Document 1).

  However, electric heaters such as those provided in conventional air conditioners can prevent freezing of water remaining in the outdoor unit base, but there is a large amount of snow and the snow is at the bottom of the outdoor unit base. Even in the area where the electric heater is used, the drain hole of the outdoor unit base is blocked by the snow. Therefore, the drainage performance of the outdoor unit as in the past is reduced.

  Therefore, it is necessary to secure a height that does not allow snow to reach the outdoor unit base by providing a snow cradle under the outdoor unit.

  In areas where there is a large amount of snow in a cold region, road heating is generally used to melt snow (see, for example, Patent Document 2).

Japanese Patent No. 3882910 (paragraph [0012]) Japanese Patent No. 4517556 (paragraph [0022])

  As described above, measures against snow accumulation in cold regions include, for example, the provision of a snow cradle to prevent snow from reaching the outdoor unit base, or the operation of an electric heater to collect the drainage accumulated in the outdoor unit base. The snow on the ground was melted by preventing water from icing and installing road heating.

  However, even if the electric heater can prevent the freezing of drain water etc. that has accumulated in the outdoor unit base, if the snow reaches the outdoor unit base, the electric heater will block the drain hole due to the influence of snow. Could not be suppressed. Therefore, it has been necessary to secure a height sufficient to prevent the snow from reaching the lower part of the outdoor unit base with the snow cradle.

  In a case where a sufficient height of the snow protection stand is ensured, for example, in an area where the amount of snow is large, snow accumulation of 5 (m) or more is assumed, and thus a height exceeding that is required. Therefore, when the height of the snow cradle is sufficiently secured, the outdoor unit is arranged at a high place, so that the serviceability is lowered. Therefore, in the case of avoiding the influence of snow on the outdoor unit base with the snow cradle, the serviceability could not be improved.

  In addition, if a snow cradle is provided and an electric heater is provided below the outdoor unit, the operation cost is increased due to an increase in demands on the operational safety in the electric heater.

  In addition, when the road heating is provided on the entire ground around the outdoor unit, it is expensive to install the snow accumulated on the ground.

  In other words, there is a problem that it is not possible to prevent water freezing in the outdoor unit base portion while improving serviceability and realizing low cost.

  The present invention has been made to solve the above-described problems, and provides an outdoor unit that can prevent freezing of water in the outdoor unit base while improving serviceability and realizing low cost. It is intended to provide.

An outdoor unit according to the present invention includes a compressor, an indoor unit side heat exchanger, an expansion device, and a first refrigerant circuit formed by connecting an outdoor unit side heat exchanger via a refrigerant pipe. a outdoor unit part of the refrigerant circuit is provided, discharged from the compressor, a second refrigerant circuit for bypassing the refrigerant flowing through the first refrigerant circuit, the outdoor supporting the compressor and the outdoor unit side heat exchanger An snow base for supporting the outdoor unit base part, and a heat medium flowing therethrough, and the heat medium and a refrigerant flowing through the second refrigerant circuit. A load heating unit that heats the surroundings through heat exchange is provided on the snow cradle.

  According to the present invention, by providing a load heating unit using a refrigeration cycle to the snow cradle, it is possible to melt the snow accumulated on the snow cradle while improving serviceability and realizing low cost. Therefore, this invention has the effect that the freezing of the water in an outdoor unit base part can be prevented, improving serviceability and implement | achieving low cost.

It is a figure which shows an example of schematic structure of the air conditioning system 1 in Embodiment 1 of this invention. It is a figure which shows an example of the external shape of the outdoor unit 7 in Embodiment 1 of this invention. It is a figure which shows an example of a function structure of the control apparatus 51 in Embodiment 1 of this invention. It is a flowchart explaining the example of control of the control apparatus 51 in Embodiment 1 of this invention. It is a figure which shows an example of schematic structure of the air conditioning system 1 in Embodiment 2 of this invention. It is a figure which shows an example of a function structure of the control apparatus 51 in Embodiment 2 of this invention. It is a flowchart explaining the control example of the control apparatus 51 in Embodiment 2 of this invention. It is a figure which shows an example of a function structure of the control apparatus 51 in Embodiment 3 of this invention. It is a flowchart explaining the control example of the control apparatus 51 in Embodiment 3 of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the step of describing the program for performing the operation of the embodiment of the present invention is a process performed in time series in the order described, but it is not always necessary to process in time series. The processing executed may be included.

  It does not matter whether each function described in the present embodiment is realized by hardware or software. That is, each block diagram described in this embodiment may be considered as a hardware block diagram or a software functional block diagram. For example, each block diagram may be realized by hardware such as a circuit device, or may be realized by software executed on an arithmetic device such as a processor (not shown).

  In addition, each block in the block diagram described in this embodiment only needs to perform its function, and the configuration may not be separated by each block. In each of the first to third embodiments, items not particularly described are the same as those in the first to third embodiments, and the same functions and configurations are described using the same reference numerals. In addition, each of Embodiments 1 to 3 may be implemented alone or in combination. In either case, the advantageous effects described below can be obtained. In addition, various specific setting examples described in this embodiment are merely examples, and are not particularly limited thereto.

Embodiment 1 FIG.
(Configuration of Embodiment 1)
FIG. 1 is a diagram showing an example of a schematic configuration of an air conditioning system 1 according to Embodiment 1 of the present invention. As shown in FIG. 1, the air conditioning system 1 includes an air conditioner 2 and a road heating unit 3. Although the load heating unit 3 will be described later in detail, it may be a commercially available one and can be attached to the air conditioner 2 as an optional part.

  The air conditioner 2 includes a main refrigerant circuit 4, a bypass circuit 5, and a load heating heat exchanger 6. The main refrigerant circuit 4 includes, for example, a compressor 11, a four-way valve 12, a gas operation valve 13, an indoor unit side heat exchanger 14, an electronic expansion valve 15, a liquid operation valve 16, a flow rate regulator 17, a heat exchanger 18, and an outdoor unit. The machine side heat exchanger 19 and the accumulator 20 are comprised. The bypass circuit 5 includes, for example, a bypass pipe 31, a bypass circuit electromagnetic valve 32, a bypass circuit electronic expansion valve 34, a bypass circuit temperature sensor 35, and the like.

  Next, a specific configuration of the air conditioner 2 will be described. The air conditioner 2 includes an outdoor unit 7 and an indoor unit 9. Among these, the outdoor unit 7 is provided with a part of the main refrigerant circuit 4 and functions as a heat source unit. The outdoor unit 7 includes, for example, a compressor 11, a four-way valve 12, a gas operation valve 13, a liquid operation valve 16, a flow rate regulator 17, a heat exchanger 18, an outdoor unit side heat exchanger 19, an accumulator 20, and the like. It has been. Among these, the outdoor unit side heat exchanger 19 functions as a heat source side heat exchanger.

  The outdoor unit 7 is provided with a control device 51 as a control function. The control device 51 has a functional configuration realized on, for example, a control board accommodated in an electrical component box of the outdoor unit 7 (not shown). Details of the functional configuration of the control device 51 will be described later with reference to FIG. 3. In short, the control device 51 is mounted on the outdoor unit 7 as a functional configuration for controlling the driving components of the outdoor unit 7 according to various sensing results. It is what is done. The control device 51 is provided with switch means 52 including various switches such as a dip switch and a rotary switch (not shown) as a physical configuration. Such various switches are accommodated in an electrical component box (not shown) as the switch means 52 and used when changing various settings.

  The outdoor unit 7 is provided with the bypass circuit 5 described above. The detection result of the bypass circuit temperature sensor 35 of the bypass circuit 5 is supplied to the control device 51. For example, the bypass circuit temperature sensor 35 is provided on the outlet side of the load heating heat exchanger 6 and detects the outlet temperature of the load heating heat exchanger 6. The bypass circuit temperature sensor 35 converts such a detection result into a detection signal based on a preset communication protocol, and supplies the detection signal to the control device 51. On the other hand, the indoor unit 9 is provided with another part of the main refrigerant circuit 4 and functions as a load-side unit. The indoor unit 9 is provided with, for example, an indoor unit side heat exchanger 14 and an electronic expansion valve 15. Among these, the indoor unit side heat exchanger 14 functions as a use side heat exchanger.

  Next, on the premise of the above configuration, a more specific configuration of the air conditioner 2 will be described. First, various specific configurations of the outdoor unit 7 will be described. The compressor 11 compresses and discharges the sucked refrigerant. For example, an inverter device (not shown) is provided in the control device 51 described later, and the operation frequency is supplied from the control device 51 to the compressor 11. The control device 51 arbitrarily controls the capacity of the compressor 11, that is, the amount of refrigerant delivered per unit time of the compressor 11 within the range of the specifications of the compressor 11 by arbitrarily changing the operation frequency.

  The four-way valve 12 switches the refrigerant flow between the cooling operation and the heating operation based on a signal supplied from the control device 51. The gas operation valve 13 controls the amount of refrigerant flowing out of the outdoor unit 7 and the amount of refrigerant flowing into the outdoor unit 7. Specifically, the gas operation valve 13 controls the outflow amount and inflow amount of a gas refrigerant such as a gaseous single-phase refrigerant or a gas-liquid two-phase refrigerant mainly composed of a gaseous refrigerant. The liquid operation valve 16 controls the amount of refrigerant flowing into the outdoor unit 7 and the amount of refrigerant flowing out of the outdoor unit 7. Specifically, the liquid operation valve 16 controls an inflow amount and an outflow amount of a liquid refrigerant such as a liquid single-phase refrigerant or a gas-liquid two-phase refrigerant mainly composed of a liquid refrigerant.

  The flow rate regulator 17 is provided in the sub refrigerant pipe 23 branched from the main refrigerant pipe 22. The auxiliary refrigerant pipe 23 has, for example, a longitudinal shape having elasticity, one of which is composed of one connection port and the other is composed of two connection ports which are divided into two. One of the auxiliary refrigerant pipes 23 is connected to the main refrigerant pipe 22 on the liquid operation valve 16 side, the first one is connected between the four-way valve 12 and the accumulator 20, and the second is an electronic circuit for bypass circuit. Connected to the downstream side of the expansion valve 34. The flow rate regulator 17 can change an opening degree, and is comprised by the valve which adjusts a flow volume. The heat exchanger 18 exchanges heat between the refrigerant flowing through the main refrigerant pipe 22 and the refrigerant flowing through the sub refrigerant pipe 23. The state of the refrigerant flowing through the sub refrigerant pipe 23 is adjusted by the flow rate regulator 17.

  The outdoor unit side heat exchanger 19 performs heat exchange between the refrigerant and the air. Specifically, the outdoor unit side heat exchanger 19 exchanges heat between the refrigerant flowing through the main refrigerant pipe 22 and outdoor air sucked from the outdoor unit 7 using a fan of the outdoor unit 7 (not shown). . The outdoor unit side heat exchanger 19 functions as an evaporator during heating operation, for example, and evaporates and evaporates the refrigerant. The outdoor unit side heat exchanger 19 functions as a condenser during cooling operation, for example, and therefore condenses and liquefies the refrigerant.

  The load heating heat exchanger 6 connects a bypass pipe 31 constituting the bypass circuit 5 and a load heating refrigerant pipe 44 constituting the load heating unit 3. When the bypass pipe 31 and the load heating refrigerant pipe 44 are connected, the load heating heat exchanger 6 circulates the refrigerant flowing through the bypass pipe 31 and the load heating refrigerant pipe 44. Heat exchange is performed with a liquid that is a heat medium. As the liquid flowing through the load heating refrigerant pipe 44, for example, an antifreeze liquid is used, so that the liquid flowing through the load heating refrigerant pipe 44 can be prevented from freezing even in a cold region.

  In the above description, an example in which a liquid antifreeze is used as an example of the heat medium flowing through the load heating refrigerant pipe 44 is not limited to this. The heat medium is a heat medium that is frozen in a cold region. As long as it does not, gas may be sufficient.

  The load heating heat exchanger 6 is provided with, for example, two connection ports for connecting the bypass pipe 31 and two connection ports for connecting the load heating refrigerant pipe 44. Each connection port provided in the heat exchanger 6 for load heating is provided with a member for connecting various pipes. For example, when the load heating unit 3 is attached to the load heating heat exchanger 6 as an option, the load heating refrigerant pipe 44 is fixed by a member for connecting various pipes, and the load heating heat exchanger 6 is fixed. In the case where the load heating unit 3 is not attached as an option, each connection port provided in the load heating heat exchanger 6 may be closed with a lid or the like adapted to the shape of each connection port.

  The members that connect the various pipes are, for example, longitudinal connection pipes composed of two connection ports. Each of the two connection ports is composed of, for example, a covering member that covers the periphery, and dissimilar metals. What is necessary is just to be comprised with the material which can be connected and has high corrosion resistance.

  As described above, the load heating heat exchanger 6 exchanges heat between the refrigerant flowing through the bypass pipe 31 and the antifreeze liquid flowing through the load heating refrigerant pipe 44. Specifically, when the load heating unit 3 becomes necessary during the heating operation, the control device 51 opens the opening degree of the bypass circuit electromagnetic valve 32 of the bypass pipe 31 so that the load heating heat is increased. The exchanger 6 exchanges heat between the refrigerant and the antifreeze liquid.

  As a result, the refrigerant flowing through the bypass pipe 31 is condensed and liquefied, so that it becomes a liquid refrigerant. The accumulator 20 is formed with a configuration for accumulating excess refrigerant, and the accumulator 20 and the bypass pipe 31 are connected. Accordingly, the liquid refrigerant condensed in the load heating heat exchanger 6 flows into the accumulator 20, and the liquid refrigerant is stored in the accumulator 20.

  The load heating unit 3 includes, for example, a heating member 41 and a pump 42. The heating member 41 is constituted by a heating pipe 43, for example. The heating member 41 is not particularly limited in terms of material, outer shape, cross-sectional shape, and the like, but may be composed of a material having high cold resistance and high durability, for example. The arrangement configuration of the heating pipe 43 is not particularly limited. For example, the heating pipe 43 may be arranged in a meandering shape so that the heat of the heating pipe 43 is easily transmitted around the load heating unit 3. For example, the pump 42 circulates an antifreeze liquid flowing through the heating pipe 43. The pump 42 is controlled by a control device 51 described later.

  Further, as described above, the load heating heat exchanger 6 exchanges heat between the refrigerant and the antifreeze liquid, so that the antifreeze liquid flowing through the load heating refrigerant pipe 44 is heated. Further, since the pump 42 is driven, the antifreeze liquid flowing through the load heating refrigerant pipe 44 circulates in the load heating unit 3. Therefore, since the heated antifreeze liquid passes through the heating pipe 43 by driving the pump 42 and circulates in the load heating unit 3, the heating member 41 can heat the surroundings. That is, the liquid circulating in the load heating unit 3 is a heat medium, and an antifreeze liquid that does not freeze even in a cold region is used. Therefore, the load heating heat exchanger 6 generates a refrigerant and a heat medium. By exchanging heat, the load heating unit 3 can heat the surroundings.

  Next, the bypass circuit 5 will be specifically described. The bypass circuit electronic expansion valve 34 is configured to change the opening degree, and adjusts the flow rate of the refrigerant flowing through the bypass pipe 31. The control device 51 obtains the degree of supercooling based on the detection result of the temperature sensor for bypass circuit 35 and the saturation temperature of the high pressure, and according to the obtained degree of supercooling, the electronic expansion valve 34 for the bypass circuit. Adjust the opening.

  The bypass circuit solenoid valve 32 is a relay that opens and closes the valve, and adjusts whether or not the refrigerant flowing through the bypass pipe 31 is allowed to pass therethrough. The control device 51 obtains a distance ΔL between the outdoor unit base 62 described later and the snow 55 based on the detection result of the snowfall sensor 91 described later. Although details of the control will be described later, the control device 51 determines whether or not to shift to the first snow removal mode in which the refrigerant is circulated in the bypass circuit 5 according to the obtained distance ΔL. When the control device 51 shifts to the first snow removal mode, the refrigerant is circulated through the bypass circuit 5 by opening the bypass circuit solenoid valve 32, and the antifreeze liquid is circulated in the load heating unit 3 by driving the pump 42. Let

  Therefore, as described above, the load heating heat exchanger 6 exchanges heat between the refrigerant and the antifreeze liquid. Note that the first snow removal mode is assumed to be an anti-icing process for preventing a state where a drain hole of the outdoor unit base 62, which will be described later, is closed.

  Next, a specific configuration of the indoor unit 9 will be described. The indoor unit 9 is provided with another part of the main refrigerant circuit 4. Specifically, the indoor unit 9 is provided with an indoor unit side heat exchanger 14 and an electronic expansion valve 15. Among these, the indoor unit side heat exchanger 14 functions as a use side heat exchanger.

  The indoor unit side heat exchanger 14 performs heat exchange between the refrigerant and the air. Specifically, the indoor unit side heat exchanger 14 exchanges heat between the refrigerant flowing through the main refrigerant pipe 22 and the indoor air sucked from the indoor unit 9 using a fan of the indoor unit 9 (not shown). . The indoor unit side heat exchanger 14 functions as a condenser during heating operation, for example, so that the refrigerant is condensed and liquefied. For example, the indoor unit-side heat exchanger 14 functions as an evaporator during the cooling operation, and thus evaporates and vaporizes the refrigerant by causing the refrigerant to take heat of the indoor air.

  The electronic expansion valve 15 is a valve that adjusts the opening degree. The electronic expansion valve 15 adjusts the pressure of the refrigerant, the flow rate of the refrigerant, and the like of the indoor unit side heat exchanger 14 by controlling the opening of the valve. Therefore, the electronic expansion valve 15 constitutes a decompression unit of the main refrigerant circuit 4. That is, the electronic expansion valve 15 constitutes a pressure adjusting means for the main refrigerant circuit 4. In the above description, it is assumed that the number of indoor units 9 is one, but the present invention is not particularly limited to this. For example, the air conditioner 2 may be configured by one outdoor unit 7 and a plurality of indoor units 9.

  Next, the refrigeration cycle formed by the main refrigerant circuit 4 during the heating operation of the air conditioner 2 will be described based on the refrigerant flow. Here, the control device 51 controls driving of the compressor 11, the four-way valve 12, the electronic expansion valve 15, the flow rate regulator 17, the bypass circuit solenoid valve 32, the bypass circuit electronic expansion valve 34, and the pump 42. Assume that. In addition to the bypass circuit temperature sensor 35, it is assumed that detection results of various sensors (not shown) are supplied to the control device 51. Further, it is assumed that the heating operation is performed in an environment where the snow 55 does not reach the outdoor unit base 62 described later.

  In the outdoor unit 7, the compressor 11 compresses and discharges the supplied refrigerant. The refrigerant discharged from the compressor 11 is a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant passes through the four-way valve 12 and the gas operation valve 13, flows out of the outdoor unit 7, and flows into the indoor unit 9. The refrigerant that has flowed into the indoor unit 9 passes through the indoor unit side heat exchanger 14 that functions as a condenser. At this time, in the indoor unit side heat exchanger 14, the refrigerant exchanges heat with indoor air to condense and liquefy, and for example, heat the air in the air-conditioning target space. Therefore, the air conditioning apparatus 2 can heat the air-conditioning target space. Next, the refrigerant that has passed through the indoor unit side heat exchanger 14 is decompressed, for example, becomes a low-temperature and low-pressure two-phase refrigerant, flows out of the indoor unit 9, and flows into the outdoor unit 7.

  The low-temperature and low-pressure two-phase refrigerant that has flowed into the outdoor unit 7 passes through the liquid operation valve 16 and flows into the outdoor unit-side heat exchanger 19 that functions as an evaporator. The refrigerant that has passed through the outdoor unit side heat exchanger 19 evaporates and gasifies by exchanging heat with outdoor air, and is further sucked into the compressor 11 via the four-way valve 12 and the accumulator 20. Next, the compressor 11 compresses and discharges the refrigerant again. As a result, the processing as described above is performed again, and the refrigerant circulates through the main refrigerant circuit 4.

  In the basic heating operation as described above, it is not necessary to supply the refrigerant to the bypass pipe 31 and to distribute the refrigerant to the bypass circuit 5, so the solenoid valve 32 for the bypass circuit is kept closed. .

  On the other hand, for example, it is assumed that the heating operation is performed in an environment in which the amount of snow is large and the snow 55 reaches the outdoor unit base 62 described later. In such an assumption, water generated during the defrosting operation freezes in the outdoor unit base 62 and closes the drain hole of the outdoor unit base 62. Furthermore, in such a situation, the outdoor unit side heat exchanger 19 is frozen, so that the heating performance may be deteriorated. Further, a state is assumed in which the road heating unit 3 is provided on the inner side of a snow protection stand 81 described later. Further, in order to secure the capability of the load heating heat exchanger 6, the degree of supercooling is obtained based on the detection result of the temperature sensor 35 for the bypass circuit, and the electronic expansion valve 34 for the bypass circuit is obtained according to the obtained degree of supercooling. Assume a state in which the degree of opening is adjusted. At this time, in order to ensure a stable capacity in the load heating heat exchanger 6, a case is assumed in which, for example, 10 (deg) is set as a target value as the degree of supercooling.

  First, the air conditioner 2 opens the bypass circuit solenoid valve 32 and supplies the bypass circuit 5 with the high-temperature and high-pressure refrigerant discharged from the compressor 11. Next, the air conditioning apparatus 2 drives the pump 42 to circulate the antifreeze liquid in the load heating unit 3. Next, the load heating heat exchanger 6 exchanges heat between the antifreeze liquid flowing through the load heating unit 3 and the high-temperature and high-pressure refrigerant discharged from the compressor 11. Therefore, the load heating unit 3 is heated. Therefore, since the load heating unit 3 melts snow below the outdoor unit base 62, the air conditioner 2 can suppress the state where the drain hole is frozen.

  The main refrigerant circuit 4 corresponds to the first refrigerant circuit in the present invention. The bypass circuit 5 corresponds to the second refrigerant circuit in the present invention. The main refrigerant pipe 22 corresponds to the refrigerant pipe in the present invention. The bypass circuit solenoid valve 32 corresponds to the first solenoid valve in the present invention. The electronic expansion valve 15 corresponds to the expansion device in the present invention. Further, the antifreeze liquid circulating in the load heating unit 3 corresponds to the heat medium in the present invention.

In addition, the refrigerant | coolant which distribute | circulates the main refrigerant circuit 4 and the bypass circuit 5 is not specifically limited. For example, the refrigerant flowing through the main refrigerant circuit 4 and the bypass circuit 5 may be a single refrigerant such as R22, a non-azeotropic refrigerant mixture such as R407C, or a pseudo-common refrigerant such as R410A. It may be a boiling refrigerant or a natural refrigerant such as CO ₂ . That is, various refrigerants can be used as the refrigerant flowing through the main refrigerant circuit 4 and the bypass circuit 5.

  Next, the arrangement configuration of the outdoor unit 7 and the load heating unit 3 will be described with reference to FIG. FIG. 2 is a diagram showing an example of the outer shape of the outdoor unit 7 according to Embodiment 1 of the present invention. As shown in FIG. 2, the outdoor unit 7 includes, for example, a casing 61, an outdoor unit base 62, a snow hood 63, a wind baffle plate 65, a baffle plate 67, and the like as outer shapes. As described above, the housing 61 accommodates a part of the main refrigerant circuit 4. The outdoor unit base 62 is provided, for example, below the housing 61 and supports a part of the main refrigerant circuit 4 housed in the housing 61. Specifically, the outdoor unit base 62 supports the compressor 11, the outdoor unit side heat exchanger 19, and the like. The outdoor unit base 62 has a drain hole (not shown).

  The snow hood 63 is provided on the upper side of the housing 61, for example, and houses a fan of the outdoor unit 7 (not shown). The snowproof hood 63 is configured with an air outlet 71. Air blown out as the fan of the outdoor unit 7 (not shown) is blown out from the blowout port 71. The air baffle plate 65 is provided at a position facing a part of the outdoor unit side heat exchanger 19, and a suction port 73 is configured. As the fan of the outdoor unit 7 (not shown) is driven, outdoor air around the outdoor unit 7 is sucked into the outdoor unit 7 from the suction port 73. The air baffle plate 67 is provided at a position facing another part of the outdoor unit side heat exchanger 19, and a suction port 75 is configured. As the fan of the outdoor unit 7 (not shown) is driven, outdoor air around the outdoor unit 7 is sucked into the outdoor unit 7 from the suction port 75.

  Below the outdoor unit 7 as described above, a snow protection stand 81 is provided. Specifically, since the snow protection stand 81 supports the outdoor unit base 62 by disposing the snow protection stand 81 below the outdoor unit base 62, the snow protection stand 81 supports the outdoor unit 7. Therefore, the snow cradle 81 can support the outdoor unit 7 at a position away from the ground 85. The road heating unit 3 is provided inside the snow proofing frame 81. The load heating unit 3 may be disposed below the snow protection stand 81 and at a position where the load is not stepped on the snow protection stand 81.

  The snow protection stand 81 includes, for example, a pedestal 82, a foot 83, and a brace 84. The pedestal 82 is opposed to the outdoor unit base 62 and serves as a table that supports the outdoor unit base 62. For example, the foot 83 supports the pedestal 82 from the ground 85, and four legs 83 are provided for the pedestal 82. The brace 84 reinforces the four legs 83.

  The snow protection stand 81 is provided with a snowfall sensor 91. For example, the snowfall sensor 91 is provided at the boundary between the pedestal 82 of the snow protection stand 81 and the outdoor unit base 62. The snowfall sensor 91 detects the snow 55 piled up on the ground 85 and supplies the detection result to the control device 51 described with reference to FIG. In addition, when the height from the ground 85 of the snow protection stand 81 and the height from the ground 85 to which the snowfall sensor 91 is attached are set in the control device 51, the snowfall sensor 91 has detected the snow 55. However, the present invention is not particularly limited to this. For example, when detecting the snow 55, the snowfall sensor 91 may calculate the height of the detected snow 55 from the ground 85 and supply the calculation result to the control device 51.

  In addition, the snowfall sensor 91 should just be comprised with the infrared sensor which detects an obstruction with infrared rays, for example. In this case, the snowfall sensor 91 can be realized at low cost. The snowfall sensor 91 may include a plurality of infrared sensors, and the plurality of infrared sensors may be arranged vertically with respect to the ground 85 at regular intervals. In this case, the snowfall sensor 91 can detect the height of the detected snow 55 from the ground 85 in stages. The snowfall sensor 91 may detect the snow 55 by detecting the outside air temperature and moisture. In this case, since the snowfall sensor 91 detects the snow 55 based on the detection result of the outside air temperature and whether or not moisture has been continuously detected for a preset time, the snowfall sensor 91 is blown by a wind from a tree or the like. Incorrect detection of snow 55 can be prevented.

  That is, the snowfall sensor 91 supplies the control device 51 with information for adjusting the amount of snow accumulation below the snow protection stand 81. For example, generally, if the distance ΔL between the lower part of the outdoor unit base 62 and the snow 55 of the snow protection stand 81 is 150 (mm), a drain hole (not shown) is not blocked. Therefore, the distance ΔL between the outdoor unit base 62 and the snow 55 on the snow protection stand 81 only needs to be secured by 150 (mm). Therefore, for example, the position where the snowfall sensor 91 is attached to the snow stand 81 may be provided on the foot 83 of the snow stand 81 that is about 150 mm away from the ground 85. Note that the various configurations of the outdoor unit 7, the snow protection stand 81, the snowfall sensor 91, and the like described above are examples, and are not particularly limited thereto.

  Next, details of the control device 51 that has been outlined above will be described with reference to FIG. FIG. 3 is a diagram illustrating an example of a functional configuration of the control device 51 according to Embodiment 1 of the present invention. As shown in FIG. 3, the control device 51 includes, for example, a transmission / reception unit 101, an operation mode determination unit 103, a snow removal mode start determination unit 105, a snow removal mode end determination unit 107, an operation stop determination unit 109, a snow removal condition determination unit 111, An operation mode control unit 113, a snow removal mode control unit 115, a main refrigerant circuit control unit 117, a bypass circuit control unit 121, a load heating unit control unit 123, and the like are included.

  For example, the transmission / reception unit 101 receives a signal supplied from the outside, and then converts it into a signal to be processed in the control device 51. For example, the transmission / reception unit 101 converts the signal processed in the control device 51 into a signal supplied to the outside, and then transmits the signal. The operation mode determination unit 103 determines the operation mode of the air conditioner 2. The snow removal mode start determination unit 105 determines whether to start the first snow removal mode. The snow removal mode end determination unit 107 determines whether or not to end the first snow removal mode. The operation stop determination unit 109 determines whether to stop the operation based on a signal supplied from the outside.

  The snow removal condition determination unit 111 includes, for example, a snow accumulation amount determination unit 131 and a timer unit 133. The snow cover amount determination unit 131 determines the snow cover amount based on the detection result of the snowfall sensor 91. The snow accumulation determination unit 131 obtains a distance ΔL between the ground 85 and the surface of the snow 55 as an index corresponding to the snow accumulation. For example, when the installation position of the snowfall sensor 91 is registered in advance and is assumed to be 150 (mm) from the ground 85, if the snowfall sensor 91 detects the snow 55, the distance ΔL between the ground 85 and the surface of the snow 55 is , 150 (mm) may be determined.

  The timer 133 counts the time that the snowfall sensor 91 is detecting, for example. For example, when the snowfall sensor 91 detects a value exceeding 350 (mm) as the distance ΔL from the ground 85 to the snow 55, the time measuring unit 133 continuously detects a value exceeding 350 (mm). Count. Note that the determination of the amount of snow as described above is an example, and the present invention is not particularly limited to this.

  The snow removal condition determination unit 111 determines the start of the first snow removal mode based on the snow accumulation amount based on the detection result of the snowfall sensor 91 and a preset start determination threshold, and determines the determination result as the snow removal mode start determination To the unit 105. The snow removal condition determination unit 111 determines the end of the first snow removal mode based on the amount of snow and the elapsed time based on the detection result of the snowfall sensor 91 and a preset end determination threshold, and the determination result is snowed. This is supplied to the mode end determination unit 107.

  The operation mode control unit 113 supplies a command corresponding to the determined operation mode to the main refrigerant circuit control unit 117. When the start of the first snow removal mode is determined, the snow removal mode control unit 115 issues a command according to the start of the first snow removal mode to the main refrigerant circuit control unit 117, the bypass circuit control unit 121, and the load heating unit control unit. 123 respectively. When the end of the first snow removal mode is determined, the snow removal mode control unit 115 issues a command corresponding to the end of the first snow removal mode to the main refrigerant circuit control unit 117, the bypass circuit control unit 121, and the load heating unit control unit. 123 respectively.

  The main refrigerant circuit control unit 117 includes an electronic expansion valve control unit 141, an electromagnetic valve control unit 143, a compressor control unit 145, a fan control unit 147, and the like, and the flow rate and direction of flow of the refrigerant circulating in the main refrigerant circuit 4 And control the pressure and the like. The electronic expansion valve control unit 141 controls, for example, the opening degree of the electronic expansion valve 15 and the opening degree of the flow rate regulator 17. The electromagnetic valve control unit 143 controls, for example, opening / closing of the gas operation valve 13 and opening / closing of the liquid operation valve 16. The four-way valve control unit 144 controls the switching operation of the four-way valve 12. The compressor control unit 145 controls driving of the compressor 11 according to the operating frequency. The fan control unit 147 controls driving of the fan of the outdoor unit 7 (not shown).

  The bypass circuit control unit 121 includes a bypass circuit solenoid valve control unit 151, a bypass circuit electronic expansion valve control unit 153, and the like, and controls the flow rate, the flow direction, the pressure, and the like of the refrigerant circulating in the bypass circuit 5. The bypass circuit solenoid valve controller 151 controls the opening and closing of the bypass circuit solenoid valve 32. The bypass circuit electronic expansion valve control unit 153 controls the opening degree of the bypass circuit electronic expansion valve 34. The load heating unit control unit 123 includes a pump control unit 155, and controls the heat medium circulating in the load heating unit 3, for example, the flow rate and flowing direction of the antifreeze liquid.

  Note that the functional configuration described above is an example, and is not particularly limited thereto, as long as the configuration described above is executed. Next, an operation example of the control device 51 including the first snow removal mode will be described with reference to FIG.

(Operation of Embodiment 1)
FIG. 4 is a flowchart for explaining a control example of the control device 51 according to Embodiment 1 of the present invention. In FIG. 4, as a default setting, the bypass circuit solenoid valve 32 is closed, the snow protection flag is set to 0, the first distance threshold is set as the start determination threshold, and the second distance is set as the end determination threshold. Assume that the threshold is set and the first time threshold is set for the detection duration determination. More specifically, a case is assumed where, for example, 250 (mm) is set as the first distance threshold, 350 (mm) is set as the second distance threshold, and 10 minutes is set as the first time threshold.

  The various setting examples described above are merely examples, and the present invention is not particularly limited thereto. For example, the threshold regarding various distances and the threshold regarding time are examples, and are changed according to the installation environment of the outdoor unit 7, that is, the amount of snow in the area.

  For example, when the outdoor unit 7 is provided in an area where the amount of snow accumulation per unit time is large compared to the case assumed above, the snow 55 accumulates earlier. Therefore, the threshold value related to various distances may be set shorter than the value assumed above, and the threshold value related to time may be set shorter than the value assumed above. In addition, for example, the snow prevention flag is merely used as an index indicating a situation in which a certain transition state is continued in order to count the detection duration time, and is not particularly limited thereto.

  Further, it is assumed that the processes in steps S15 to S21 are in the first snow removal mode. That is, it is assumed that the process of step S11 to step S14 is a first snow removal mode pre-process, and the process of step S22 to step S24 is a first snow removal mode post-process.

(First snow removal mode pre-process)
(Step S11)
The control device 51 determines the operation mode.

(Step S12)
The control device 51 determines whether or not the heating operation is being performed. When the heating operation is being performed, the control device 51 proceeds to step S13. On the other hand, the control apparatus 51 returns to step S11, when heating operation is not performed.

(Step S13)
The control device 51 acquires the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81.

(Step S14)
The control device 51 determines whether or not the distance ΔL between the outdoor unit base portion 62 and the snow 55 on the snow protection stand 81 is less than the first distance threshold. When the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow protection stand 81 is less than the first distance threshold, the control device 51 proceeds to step S15. On the other hand, when the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81 is not less than the first distance threshold, the control device 51 proceeds to step S11.

(First snow removal mode processing)
(Step S15)
The control device 51 opens the bypass circuit solenoid valve 32.

(Step S16)
The control device 51 acquires the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81.

(Step S17)
The control device 51 determines whether or not the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow protection stand 81 is equal to or greater than the second distance threshold. When the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81 is not less than the second distance threshold, the control device 51 proceeds to step S18. On the other hand, when the distance ΔL between the outdoor unit base portion 62 and the snow 55 of the snow protection stand 81 is not equal to or greater than the second distance threshold, the control device 51 proceeds to step S24.

(Step S18)
The control device 51 sets the snow protection flag to 1.

(Step S19)
The control device 51 counts the detection continuation time during which the state where the snow prevention flag is 1 is continued.

(Step S20)
The control device 51 determines whether or not the detection duration time during which the snowproof flag is 1 has passed the first time threshold. The control device 51 proceeds to step S21 when the detection continuation time in which the snowproof flag is 1 continues for the first time threshold. On the other hand, the control apparatus 51 returns to step S16, when the detection continuation time which has continued the state in which the snow prevention flag is 1 does not pass a 1st time threshold value.

(Step S21)
The control device 51 sets the snow prevention flag to 0, and proceeds to step S20.

(Processing after the first snow removal mode)
(Step S22)
The controller 51 closes the bypass circuit solenoid valve 32.

(Step S23)
The control device 51 determines whether or not an operation stop command has arrived. When the operation stop command has arrived, the control device 51 proceeds to step S23. On the other hand, if the operation stop command does not arrive, the control device 51 returns to step S11.

(Step S24)
The control device 51 stops the operation and ends the process.

(Effect of Embodiment 1)
As a result, the outdoor unit 7 is provided with the bypass circuit 5 so that the load heating unit 3 using the refrigeration cycle heats the surroundings. Then, the load heating unit 3 is provided on the snow protection stand 81 to heat the periphery of the snow protection stand 81. Therefore, even if the snow 55 starts to accumulate on the snow protection stand 81, the outdoor unit 7 can melt the snow 55 accumulated on the snow protection stand 81 by operating the load heating unit 3.

  Therefore, even if the outdoor unit 7 is installed in an environment where the outside air temperature is low and the amount of snow is large, the water generated at the time of defrosting in the heating operation does not freeze, so the drain hole of the outdoor unit base 62 is not blocked. . Therefore, since the outdoor unit 7 can discharge the water stored in the outdoor unit base 62 to the outside, the heat exchange efficiency of the outdoor unit side heat exchanger 19 is not lowered and the deterioration of the heating performance can be suppressed. it can. Further, since the refrigerant that flows out of the bypass pipe 31 flows into the accumulator 20, the compressor 11 does not suck in the liquid refrigerant. Therefore, the main refrigerant circuit 4 can improve the reliability of the outdoor unit 7.

  Moreover, since it is not necessary to raise the snow-protection stand 81 until it exceeds the maximum snow accumulation amount assumed in the area where the outdoor unit 7 is provided, the height of the snow-protection stand 81 may be a design dimension used in normal construction. Therefore, it is not necessary to ensure a sufficient height of the snow protection stand 81, so that the serviceability of the outdoor unit 7 can be improved.

  Moreover, the load heating unit 3 should just be the size which can melt the snow 55 accumulated on the periphery of the snow-protection stand 81. FIG. Therefore, the load heating unit 3 is constructed at a low cost. A heat pump type refrigeration cycle is used as a heat source for heating the load heating unit 3. Therefore, the load heating unit 3 using the heat pump type refrigeration cycle can have high safety in operation and can be operated with low power consumption. Therefore, the operation cost spent for melting snow using the road heating unit 3 is low. Therefore, the load heating unit 3 can be constructed at a low cost, and the load heating unit 3 can be operated at a low cost.

  Therefore, the outdoor unit 7 can melt the snow 55 that has accumulated on the snow protection stand 81 while improving serviceability and realizing low cost. Therefore, the outdoor unit 7 can prevent freezing of water in the outdoor unit base 62 while improving serviceability and realizing low cost. Therefore, the outdoor unit 7 can improve the serviceability and realize low cost, while suppressing root ice and a decrease in air conditioning capability due to freezing of water in the outdoor unit base 62.

  As described above, in the first embodiment, the main refrigerant formed by connecting the compressor 11, the indoor unit side heat exchanger 14, the electronic expansion valve 15, and the outdoor unit side heat exchanger 19 through the main refrigerant pipe 22. Among the circuits 4, an outdoor unit 7 provided with a part of the main refrigerant circuit 4, a bypass circuit 5 that bypasses the refrigerant discharged from the compressor 11 and flowing through the main refrigerant circuit 4, and the main refrigerant circuit 4 And an outdoor unit base 62 that supports the compressor 11 and the outdoor unit-side heat exchanger 19, and controls the flow rate of the refrigerant flowing through the bypass circuit 5 and the flow rate of the refrigerant flowing through the bypass circuit 5. A snow guard frame 81 that supports the outdoor unit base unit 62 is provided below the unit 62, and a heat medium flows through the heat medium and heat is exchanged between the heat medium and the refrigerant that flows through the bypass circuit 5 to heat the surroundings. Heating unit 3 prevents The outdoor unit 7 is configured provided to the frame 81.

  With the above-described configuration, the outdoor unit 7 can improve the serviceability and achieve low cost, while preventing freezing of water in the outdoor unit base 62. Therefore, the outdoor unit 7 can improve the serviceability and realize low cost, while suppressing root ice and a decrease in air conditioning capability due to freezing of water in the outdoor unit base 62.

  In the first embodiment, the bypass circuit 5 is connected to the suction side piping of the compressor 11 and the discharge side piping of the compressor 11, respectively, and bypass piping 31 for bypassing the refrigerant and bypass piping. And a bypass circuit solenoid valve 32 that adjusts the flow rate of the refrigerant flowing through 31.

  In the first embodiment, the snow protection stand 81 includes a snowfall sensor 91 that detects snow 55 that has accumulated on the periphery of the snow protection stand 81, and the control device 51 is detected by the outdoor unit base 62 and the snowfall sensor 91. The road heating unit 3 is operated by controlling the solenoid valve 32 for the bypass circuit according to the distance ΔL from the snow 55.

  In the first embodiment, the load heating unit 3 is provided inside or below the snow cradle 81.

  In the first embodiment, the heat medium is composed of an antifreeze liquid.

  With the configuration described above, the outdoor unit 7 can prevent water icing in the outdoor unit base 62 while remarkably improving serviceability and realizing low cost.

Embodiment 2. FIG.
The difference from the first embodiment is that an electromagnetic valve 36 for gas refrigerant is provided between the discharge side of the compressor 11 and the gas operation valve 13 so that the refrigerant is not supplied to the indoor unit-side heat exchanger 14. Thus, snow can be removed even during the heating stop period.

(Configuration of Embodiment 2)
FIG. 5 is a diagram illustrating an example of a schematic configuration of the air-conditioning system 1 according to Embodiment 2 of the present invention. As shown in FIG. 5, a gas refrigerant solenoid valve 36 is provided between the four-way valve 12 and the gas operation valve 13. That is, in the heating operation, when the four-way valve 12 is switched and the discharge side of the compressor 11 and the indoor unit side heat exchanger 14 are connected, as described above, the compressor 11 A gas refrigerant solenoid valve 36 is provided between the discharge side and the gas operation valve 13.

  The gas refrigerant solenoid valve 36 corresponds to the second solenoid valve in the present invention.

  By providing the gas refrigerant solenoid valve 36, it is possible to control whether or not the gas refrigerant flows into the indoor unit side heat exchanger 14. That is, the gas refrigerant solenoid valve 36 can control the inflow of the gas refrigerant into the indoor unit 9.

  For example, the case where heating stop time becomes long is assumed. In this case, the load heating unit 3 does not operate during the heating operation stop period. Therefore, the snow 55 may reach the lower part of the outdoor unit base 62. Furthermore, if the state where the snow 55 reaches the lower part of the outdoor unit base 62 continues for a long time, the drain hole provided in the outdoor unit base 62 may be blocked. For example, in the case of shifting to 21:00, the heating operation is stopped, and when the scheduled operation for restarting the heating operation from 7 o'clock the next day is performed, the heating operation stop period continues from 21:00 the previous day to 7 o'clock the next day. The road heating unit 3 does not operate. Under such circumstances, it is assumed that the snow 55 that accumulates on the ground 85 may reach the lower part of the outdoor unit base 62 in an area with a large amount of snow.

  Therefore, the control device 51 operates the gas refrigerant solenoid valve 36 to perform control such that the refrigerant is not supplied to the indoor unit side heat exchanger 14 when a certain condition is satisfied after the heating operation is stopped. Next, an example of a functional configuration that performs the above-described operation will be described with reference to FIG.

  FIG. 6 is a diagram illustrating an example of a functional configuration of the control device 51 according to Embodiment 2 of the present invention. As shown in FIG. 6, the transmission / reception unit 101, the snow removal mode start determination unit 105, the snow removal mode end determination unit 107, the snow removal condition determination unit 111, the operation mode control unit 113, the snow removal mode control unit 115, the main refrigerant circuit control unit 117, A bypass circuit control unit 121 and a load heating unit control unit 123 are configured. That is, compared to the case of the first embodiment described with reference to FIG. 3, the operation mode determination unit 103 and the operation stop determination unit 109 do not exist in FIG. 6 that describes the second embodiment. .

  Among the functional configurations shown in FIG. 6 for explaining the second embodiment, the transmission / reception unit 101, the snow removal mode start determination unit 105, the snow removal mode end determination unit 107, the operation mode control unit 113, the snow removal mode control unit 115, and a bypass circuit Since the control unit 121 and the load heating unit control unit 123 are the same as those in FIG. 3 described in the first embodiment, their descriptions are omitted.

  Of the configuration of the snow removal condition determination unit 111, the snow accumulation amount determination unit 131 is the same as the functional configuration shown in FIG. Among the configurations of the snow removal condition determination unit 111, the time measuring unit 133 uses a stop time, an elapsed time, a detection duration, and various threshold values for counting. The setting determination unit 135 determines whether or not the second snow removal mode is set. The second snow removal mode is set by, for example, a dip switch or a rotary switch provided in the outdoor unit 7. Among the configurations of the main refrigerant circuit control unit 117, the gas refrigerant solenoid valve control unit 149 is a newly added functional configuration. The gas refrigerant solenoid valve controller 149 controls opening and closing of the gas refrigerant solenoid valve 36.

  Next, the operation in the second snow removal mode will be described with reference to FIG. In addition, as the assumed setting, in the second snow removal mode pre-process, the operation stop state is set by the stop flag, and the time threshold for continuing the operation stop state is set by the second time threshold value. The first start threshold is set to continue the state for a predetermined time, the first distance threshold is set in the same manner as described above, and the second start occurs when the distance ΔL satisfies the condition of less than the first distance threshold. A state in which the second snow removal mode is set is set with the threshold value, and the third start threshold value is set. In addition, as the second time threshold, for example, a continuous time T1 is set. For example, the continuous time T2 is set as the third time threshold.

  Further, as an assumed setting, in the second snow removal mode process, the second distance threshold and the detection duration are set in the same manner as described above, and the case where the detection duration has passed the first time threshold is the first end threshold. A case where the elapsed time is equal to or greater than the third time threshold is set as the second end threshold. Further, for example, the elapsed time here is an elapsed time from the start of control by the control device 51 to the present, and a third time threshold is set to, for example, the continuous time T2 as a threshold for determining it. ing.

  Each of the first start threshold, the second start threshold, and the third start threshold is set to 0 as a default value. Each of the first end threshold and the second end threshold is set to 0 as a default value. Further, the continuous time T1 and the continuous time T2 are set to values according to the surrounding environment in which the outdoor unit 7 is provided.

  In addition, the heating prohibition flag set in the second snow removal mode process and reset in the second snow removal mode post-process process indicates a state in which the heating operation is prohibited in the second snow removal mode, It is not particularly limited to this. In short, the second snow removal mode and the heating operation may be operations that are exclusively controlled. Further, for example, the snow prevention flag is not particularly limited because it is merely used for counting the detection duration time and is only used as an index indicating a situation where the transition state continues.

  The various setting examples described above are merely examples, and the present invention is not particularly limited thereto. For example, the threshold regarding various distances and the threshold regarding time are examples, and are changed according to the installation environment of the outdoor unit 7, that is, the amount of snow in the area.

  In addition, the process of step S44-step S58 assumes that it is the 2nd snow removal mode process. Moreover, the process of step S31-step S43 is a 2nd snow removal mode pre-process. It is assumed that the processes in steps S59 to S61 are second snow removal mode post-process processes.

(Operation of Embodiment 2)
FIG. 7 is a flowchart for explaining a control example of the control device 51 according to Embodiment 2 of the present invention. It is assumed that the heating operation is prohibited while the heating prohibition flag is set to 1.

(Second snow removal mode pre-process)
(Step S31)
The control device 51 initializes various flags.

(Step S32)
The control device 51 determines whether or not the operation is stopped. When the operation is stopped, the control device 51 proceeds to step S33. On the other hand, when the operation is not stopped, the control device 51 returns to step S32.

(Step S33)
The control device 51 sets the stop flag to 1.

(Step S34)
The control device 51 counts the stop time in which the stop flag is kept at 1.

(Step S35)
The control device 51 determines whether or not the stop time has passed the second time threshold. When the stop time has exceeded the second time threshold, the control device 51 proceeds to step S36. On the other hand, the control apparatus 51 returns to step S34, when stop time does not pass the 2nd time threshold value.

(Step S36)
The control device 51 sets the first start threshold value to 1.

(Step S37)
The control device 51 acquires the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81.

(Step S38)
The control device 51 determines whether or not the distance ΔL is less than the first distance threshold. If the distance ΔL is less than the first distance threshold, the control device 51 proceeds to step S39. On the other hand, if the distance ΔL is not less than the first distance threshold, the control device 51 proceeds to step S32.

(Step S39)
The control device 51 sets the second start threshold value to 1.

(Step S40)
The control device 51 determines whether or not the second snow removal mode is set. When the second snow removal mode is set, the control device 51 proceeds to step S41. On the other hand, the control apparatus 51 returns to step S32, when the 2nd snow removal mode is not set.

(Step S41)
The control device 51 sets the third start threshold value to 1.

(Step S42)
The control device 51 performs an AND operation on the first start threshold, the second start threshold, and the third start threshold.

(Step S43)
The control device 51 determines whether or not the execution result of the AND operation is 1. When the execution result of the AND operation is 1, the control device 51 proceeds to step S44. On the other hand, if the execution result of the AND operation is not 1, the control device 51 returns to step S32.

(Second snow removal mode processing)
(Step S44)
The control device 51 closes the gas refrigerant solenoid valve 36.

(Step S45)
The control device 51 opens the bypass circuit solenoid valve 32.

(Step S46)
The control device 51 sets the heating prohibition flag of the indoor unit side heat exchanger 14 to 1. That is, the control device 51 sets the heating prohibition state of the indoor unit side heat exchanger 14.

(Step S47)
The control device 51 counts the elapsed time after starting the control.

(Step S48)
The control device 51 acquires the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81.

(Step S49)
The control device 51 determines whether or not the distance ΔL is greater than or equal to the second distance threshold. If the distance ΔL is greater than or equal to the second distance threshold, the control device 51 proceeds to step S50. On the other hand, if the distance ΔL is not greater than or equal to the second distance threshold, the control device 51 proceeds to step S58.

(Step S50)
The control device 51 sets the snow protection flag to 1.

(Step S51)
The control device 51 counts the detection continuation time during which the snowproof flag continues to be 1.

(Step S52)
The control device 51 determines whether or not the detection duration has exceeded the first time threshold. When the detection duration time has exceeded the first time threshold, the control device 51 proceeds to step S53. On the other hand, the control apparatus 51 returns to step S51, when detection continuation time does not pass the 1st time threshold value.

(Step S53)
The control device 51 sets the first end threshold value to 1.

(Step S54)
The control device 51 determines whether or not the elapsed time is equal to or greater than a third time threshold value. If the elapsed time is greater than or equal to the third time threshold, the control device 51 proceeds to step S55. On the other hand, if the elapsed time is not greater than or equal to the third time threshold, the control device 51 proceeds to step S56.

(Step S55)
The control device 51 sets the second end threshold value to 1.

(Step S56)
The control device 51 performs an OR operation between the first end threshold and the second end threshold.

(Step S57)
The control device 51 determines whether or not the execution result of the OR operation is 1. If the execution result of the OR operation is 1, the control device 51 proceeds to step S59. On the other hand, if the execution result of the OR operation is not 1, the control device 51 returns to step S48.

(Step S58)
The control device 51 sets the snow protection flag to 0 and returns to step S48.

(Second snow removal mode post-processing)
(Step S59)
The control device 51 opens the gas refrigerant solenoid valve 36.

(Step S60)
The controller 51 closes the bypass circuit solenoid valve 32.

(Step S61)
The control device 51 sets the heating prohibition flag of the indoor unit side heat exchanger 14 to 0, and ends the process. That is, the control device 51 cancels the heating prohibited state of the indoor unit side heat exchanger 14.

(Effect of Embodiment 2)
As a result, since the outdoor unit 7 does not transition to the heating operation in the state of transition to the second snow removal mode, the high-temperature and high-pressure gas refrigerant is not supplied to the indoor unit-side heat exchanger 14, and the compressor 11 The discharged high-temperature and high-pressure gas refrigerant can be supplied to the bypass circuit 5. Accordingly, the outdoor unit 7 can heat the load heating unit 3 because the refrigerant and the heat medium can be exchanged with the heat exchanger 6 for load heating even when the heating operation is stopped. .

  Therefore, the outdoor unit 7 can melt the snow 55 accumulated under the outdoor unit base 62, and as a result, can remove snow. Therefore, the outdoor unit 7 can remove the snow 55 that has accumulated on the lower part of the snow cradle 81 even when the heating operation is stopped.

  As described above, in the second embodiment, the gas refrigerant that is provided between the indoor unit side heat exchanger 14 and the discharge side of the compressor 11 and adjusts the flow rate of the refrigerant supplied to the indoor unit side heat exchanger 14. The control device 51 is configured to close the gas refrigerant solenoid valve 36 and open the bypass circuit solenoid valve 32 when the heating operation is stopped.

  With the above configuration, the outdoor unit 7 can perform snow removal even during the heating stop period.

Embodiment 3 FIG.
The difference from Embodiment 1 and Embodiment 2 is that the operating frequency of the compressor 11 is made higher than that of a normal one during snow removal.

(Configuration of Embodiment 3)
FIG. 8 is a diagram illustrating an example of a functional configuration of the control device 51 according to Embodiment 3 of the present invention. The difference from the first embodiment and the second embodiment is that the set value of the rapid snow removal operation frequency is supplied to the compressor control unit 145. The operation frequency for quick snow removal can be set by a dip switch or the like provided in an electric box (not shown) of the outdoor unit 7. As the operation frequency for quick snow removal, for example, a value with a higher operation frequency is set as compared with the operation frequency during normal operation. The rapid snow removal operation frequency can be set when the second snow removal mode is set.

(Operation of Embodiment 3)
FIG. 9 is a flowchart for explaining a control example of the control device 51 according to Embodiment 3 of the present invention. The difference from the second embodiment is that a process that has not been performed during the second snow removal mode process is added, which is a technique for controlling the compressor 11 at the rapid snow removal operation frequency. It is assumed that the heating operation is prohibited while the heating prohibition flag is set to 1.

  It is assumed that the processes in steps S84 to S99 are the third snow removal mode process. Moreover, the process of step S71-step S83 is a 2nd snow removal mode pre-process. It is assumed that the processes in steps S100 to S103 are second snow removal mode post-process processes.

(Third snow removal mode pre-process)
(Step S71)
The control device 51 initializes various flags.

(Step S72)
The control device 51 determines whether or not the operation is stopped. When the operation is stopped, the control device 51 proceeds to step S73. On the other hand, when the operation is not stopped, the control device 51 returns to step S72.

(Step S73)
The control device 51 sets the stop flag to 1.

(Step S74)
The control device 51 counts the stop time in which the stop flag is kept at 1.

(Step S75)
The control device 51 determines whether or not the stop time has passed the second time threshold. When the stop time has exceeded the second time threshold, the control device 51 proceeds to step S76. On the other hand, the control apparatus 51 returns to step S74, when stop time does not pass the 2nd time threshold value.

(Step S76)
The control device 51 sets the first start threshold value to 1.

(Step S77)
The control device 51 acquires the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81.

(Step S78)
The control device 51 determines whether or not the distance ΔL is less than the first distance threshold. If the distance ΔL is less than the first distance threshold, the control device 51 proceeds to step S79. On the other hand, if the distance ΔL is not less than the first distance threshold, the control device 51 proceeds to step S72.

(Step S79)
The control device 51 sets the second start threshold value to 1.

(Step S80)
The control device 51 determines whether or not the second snow removal mode is set. When the second snow removal mode is set, the control device 51 proceeds to step S81. On the other hand, when the second snow removal mode is not set, the control device 51 returns to step S72.

(Step S81)
The control device 51 sets the third start threshold value to 1.

(Step S82)
The control device 51 performs an AND operation on the first start threshold, the second start threshold, and the third start threshold.

(Step S83)
The control device 51 determines whether or not the execution result of the AND operation is 1. If the execution result of the AND operation is 1, the control device 51 proceeds to step S84. On the other hand, when the execution result of the AND operation is not 1, the control device 51 returns to step S72.

(Third snow removal mode processing)
(Step S84)
The control device 51 closes the gas refrigerant solenoid valve 36.

(Step S85)
The control device 51 opens the bypass circuit solenoid valve 32.

(Step S86)
The control device 51 controls the compressor 11 at the rapid snow removal operation frequency.

(Step S87)
The control device 51 sets the heating prohibition flag of the indoor unit side heat exchanger 14 to 1. That is, the control device 51 sets the heating prohibition state of the indoor unit side heat exchanger 14.

(Step S88)
The control device 51 counts the elapsed time after starting the control.

(Step S89)
The control device 51 acquires the distance ΔL between the outdoor unit base 62 and the snow 55 of the snow cradle 81.

(Step S90)
The control device 51 determines whether or not the distance ΔL is greater than or equal to the second distance threshold. If the distance ΔL is greater than or equal to the second distance threshold, the control device 51 proceeds to step S91. On the other hand, if the distance ΔL is not equal to or greater than the second distance threshold, the control device 51 proceeds to step S99.

(Step S91)
The control device 51 sets the snow protection flag to 1.

(Step S92)
The control device 51 counts the detection continuation time during which the snowproof flag continues to be 1.

(Step S93)
The control device 51 determines whether or not the detection duration has exceeded the first time threshold. When the detection continuation time has passed the first time threshold, the control device 51 proceeds to step S94. On the other hand, the control apparatus 51 returns to step S92, when the detection continuation time does not pass the 1st time threshold value.

(Step S94)
The control device 51 sets the first end threshold value to 1.

(Step S95)
The control device 51 determines whether or not the elapsed time is equal to or greater than a third time threshold value. If the elapsed time is greater than or equal to the third time threshold, the control device 51 proceeds to step S96. On the other hand, if the elapsed time is not greater than or equal to the third time threshold, the control device 51 proceeds to step S97.

(Step S96)
The control device 51 sets the second end threshold value to 1.

(Step S97)
The control device 51 performs an OR operation between the first end threshold and the second end threshold.

(Step S98)
The control device 51 determines whether or not the execution result of the OR operation is 1. When the execution result of the OR operation is 1, the control device 51 proceeds to step S100. On the other hand, if the execution result of the OR operation is not 1, the control device 51 returns to step S89.

(Step S99)
The control device 51 sets the snow prevention flag to 0 and returns to step S89.

(Third snow removal mode post-processing)
(Step S100)
The control device 51 opens the gas refrigerant solenoid valve 36.

(Step S101)
The controller 51 closes the bypass circuit solenoid valve 32.

(Step S102)
The control device 51 returns the operating frequency of the compressor 11 to a normal one.

(Step S103)
The control device 51 sets the heating prohibition flag of the indoor unit side heat exchanger 14 to 0, and ends the process. That is, the control device 51 cancels the heating prohibited state of the indoor unit side heat exchanger 14.

(Effect of Embodiment 3)
As a result, since the operation frequency of the compressor 11 can be changed according to the installation environment, the outdoor unit 7 drives the operation frequency of the compressor 11 at a high snow removal operation frequency higher than that of a normal one during snow removal. be able to. Therefore, since the outdoor unit 7 drives the compressor 11 at an operation frequency according to the installation environment, the heat exchange amount of the load heating heat exchanger 6 can be increased according to the amount of snowfall. Therefore, the outdoor unit 7 can increase the heating amount per unit time of the load heating unit 3. Therefore, by changing the setting according to the amount of snowfall, the outdoor unit 7 can shorten the snow removal time or increase the snow removal amount per unit time.

  As described above, in the third embodiment, the switch unit 52 is further provided, and the control device 51 increases the operation frequency of the compressor 11 in accordance with the setting content of the switch unit 52 when the heating operation is stopped.

  With the above configuration, the outdoor unit 7 can shorten the snow removal time or increase the amount of snow removal per unit time.

  As described above, in Embodiments 1 to 3, the outdoor unit 7 of the air conditioner 2 has been described. For example, a system in which the outdoor unit-side heat exchanger 19 functions as an evaporator is a hot water supply system or the like. In addition, the technology described in the first to third embodiments can be applied to other refrigeration systems that are driven by a heat pump system.

  DESCRIPTION OF SYMBOLS 1 Air conditioning system, 2 Air conditioning apparatus, 3 Road heating unit, 4 Main refrigerant circuit, 5 Bypass circuit, 6 Heat exchanger for load heating, 7 Outdoor unit, 9 Indoor unit, 11 Compressor, 12 Four-way valve, 13 Gas operation valve, 14 indoor unit side heat exchanger, 15 electronic expansion valve, 16 liquid operation valve, 17 flow regulator, 18 heat exchanger, 19 outdoor unit side heat exchanger, 20 accumulator, 22 main refrigerant piping, 23 Sub refrigerant piping, 31 Bypass piping, 32 Bypass circuit solenoid valve, 34 Bypass circuit electronic expansion valve, 35 Bypass circuit temperature sensor, 36 Gas refrigerant solenoid valve, 41 Heating member, 42 Pump, 43 Heating pipe, 44 Road heating refrigerant piping, 51 control device, 52 switch means, 55 snow, 61 housing, 62 outdoor Base part, 63 Snowproof hood, 65, 67 Air baffle, 71 Air outlet, 73, 75 Air inlet, 81 Snow guard, 82 Base, 83 Foot, 84 Bracing, 85 Ground, 91 Snowfall sensor, 101 Transceiver, 103 Operation mode determination unit, 105 Snow removal mode start determination unit, 107 Snow removal mode end determination unit, 109 Operation stop determination unit, 111 Snow removal condition determination unit, 113 Operation mode control unit, 115 Snow removal mode control unit, 117 Refrigerant circuit control unit, 121 Bypass circuit control unit, 123 Load heating unit control unit, 131 Snow accumulation determination unit, 133 Timekeeping unit, 135 Setting determination unit, 141 Electronic expansion valve control unit, 143 Electromagnetic valve control unit, 144 Four-way valve control unit, 145 Compressor Control unit, 147 Fan control unit, 149 Gas refrigerant solenoid valve control unit, 151 Solenoid valve control unit for scan circuit, 153 a bypass circuit for an electronic expansion valve, 155 pump control unit.

Claims (7)

Of the first refrigerant circuit formed by connecting the compressor, the indoor unit side heat exchanger, the expansion device, and the outdoor unit side heat exchanger via the refrigerant pipe, a part of the first refrigerant circuit is provided. An outdoor unit,
A second refrigerant circuit that bypasses the refrigerant discharged from the compressor and flowing through the first refrigerant circuit ;
And an outdoor unit base portion for supporting the front Symbol compressor and the outdoor unit side heat exchanger,
With
Below the outdoor unit base, a snow cradle is provided to support the outdoor unit base.
A load heating unit that heats the surroundings by heat exchange between the heat medium and the heat medium and the refrigerant that flows through the second refrigerant circuit is provided in the snow cradle. Outdoor unit. The second refrigerant circuit includes
A bypass pipe connected to a suction side pipe of the compressor and a discharge side pipe of the compressor, respectively, to bypass the refrigerant;
A first solenoid valve for adjusting a flow rate of the refrigerant flowing through the bypass pipe;
The outdoor unit according to claim 1, further comprising: A controller for controlling the flow rate of the refrigerant flowing through the first refrigerant circuit and the flow rate of the refrigerant flowing through the second refrigerant circuit;
The snow cradle is
It has a snowfall sensor that detects snow that has accumulated around the snow protection stand,
The control device includes:
The load heating unit is operated by controlling the first electromagnetic valve in accordance with a distance between the outdoor unit base portion and the snow detected by the snowfall sensor. The outdoor unit described in. A second solenoid valve that is provided between the indoor unit-side heat exchanger and the discharge side of the compressor and adjusts the flow rate of the refrigerant supplied to the indoor unit-side heat exchanger;
Further comprising
The control device includes:
The outdoor unit according to claim 3, wherein when the heating operation is stopped, the second electromagnetic valve is closed and the first electromagnetic valve is opened. Further comprising switch means,
The control device includes:
5. The outdoor unit according to claim 4, wherein when the heating operation is stopped, the operation frequency of the compressor is increased according to a setting content of the switch unit. The load heating unit is:
The outdoor unit according to claim 1, wherein the outdoor unit is provided inside or below the snow protection stand. The outdoor unit according to any one of claims 1 to 6, wherein the heat medium is made of an antifreeze liquid.

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