Heat pump device

Abstract

The inside of a housing (30) is partitioned into a blower chamber (RA) and a machine chamber (RB) by a partition plate (34). A blower (17) and a heat exchanger (13) are disposed in the blower chamber. At least a portion of a refrigerant circuit (10) and a compressor (11) is disposed in the machine chamber. At least a portion of an electrical component box (25) is disposed in an upper portion of the blower chamber. The electrical component box comprises: an air introduction part (57) that causes, by driving the blower, air outside the housing to flow into the electrical component box without going through the machine chamber; and an air outflow part (66) that causes air flowing inside the electrical component box to flow out. The air outflow part is disposed in a surface along which air taken in by driving of the blower and passed through the heat exchanger flows.

Description

Heat pump device

[0001] The present invention relates to a heat pump device.

[0002] For example, Patent Document 1 discloses an outdoor unit of an air conditioner serving as a heat pump device, in which the interior of a housing is partitioned into a blower chamber and a machine room by a partition plate, a heat exchanger and a blower are arranged in the blower chamber, and a compressor and a control board are arranged in the machine room. Electronic components that generate heat when driving the blower and the compressor are mounted on the control board arranged in the machine room. In Patent Document 1, a vent is provided in the partition plate, external air is taken into the machine room by rotation of the blower, and drawn into the blower chamber through the vent, thereby generating an air flow in the machine room. The heat-generating electronic components are cooled by being brought into contact with the air flow, thereby suppressing temperature rise.

[0003] By the way, with the increasing environmental awareness in recent years, heat pump devices using flammable refrigerants with low GWP (Global Warming Potential) (for example, R290) have attracted attention.

[0004] Japanese Unexamined Patent Publication No. 2003-106569

[0005] When a flammable refrigerant is used in the heat pump device of Patent Document 1, if the flammable refrigerant leaks from the refrigerant circuit in the machine room, cooling air containing the flammable refrigerant comes into contact with the electronic components. Therefore, if a spark is generated in the electronic component, the flammable refrigerant may catch fire.

[0006] Therefore, the present invention has been made to solve such problems, and an object of the present invention is to provide a heat pump device capable of preventing flammable refrigerant leaking in a machine room from coming into contact with electronic components mounted on a control board to ensure safety, and also preventing deterioration and failure of the electronic components by reliably cooling the heat-generating electronic components with an air flow.

[0007] One aspect of the present invention provides a housing containing a compressor forming a refrigerant circuit through which a flammable refrigerant circulates, a heat exchanger, a blower for circulating air through the heat exchanger, a control board for controlling the compressor and blower, and an electrical component box housing the control board. The inside of the housing is divided into a blower room and a machine room by a partition plate, with the blower and heat exchanger located in the blower room, and the compressor and at least a portion of the refrigerant circuit located in the machine room. At least a portion of the electrical component box is located above the blower room. The electrical component box includes an air inlet that allows air from outside the housing to flow into the electrical component box without going through the machine room when driven by the blower, and an air outlet that allows the air that has flowed inside the electrical component box to flow out. The air outlet is located on the surface along which the airflow that has been drawn in by the blower and passed through the heat exchanger follows.

[0008] The heat pump device of the present invention ensures safety by preventing flammable refrigerant leaked in the machine room from coming into contact with electronic components mounted on the control board, and prevents deterioration and failure of electronic components by reliably cooling them with airflow.

[0009] This is a circuit diagram showing a hot water heating system, which is an example of a heat pump device according to the present invention. This is a perspective view of the outdoor unit of the hot water heating system from the front. This is a perspective view of the outdoor unit of the hot water heating system from the rear. This is a perspective view of the internal structure of the outdoor unit of the hot water heating system from the front. This is a view from above of the inside of the electrical equipment box located in the outdoor unit of the hot water heating system. This is a view taken along the line A-A in Figure 5. This is a perspective view of the outdoor unit of the hot water heating system from diagonally below the front. This is a diagram showing the positional relationship between the air outlet of the electrical equipment box located in the blower room and the outdoor blower.

[0010] Next, embodiments of the present invention will be described with reference to the drawings. The embodiments shown below illustrate devices and methods for realizing the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not limited to the materials, shapes, structures, arrangements, etc. of the components described below. The technical idea of ​​the present invention can be modified in various ways within the technical scope defined by the claims described in the patent claims.

[0011] [Configuration of Hot Water Heating System] Figure 1 is a circuit diagram showing an example of the refrigerant circuit and water circuit of a hot water heating system 1, which is an example of a heat pump system according to the present invention. The hot water heating system 1 of this embodiment includes an outdoor unit 2 and an indoor unit 3, and these outdoor unit 2 and indoor unit 3 are connected by water piping to form a water circuit 4. The hot water heating system 1 cools or heats the room (space) in which the indoor unit 3 is located by circulating chilled water or hot water through the water circuit 4 of the outdoor unit 2 and the indoor unit 3. In Figure 1, the hot water heating system 1 is illustrated as having one indoor unit 3, but it may also have multiple indoor units 3 connected in parallel to the outdoor unit 2.

[0012] The outdoor unit 2 includes a compressor 11, a four-way valve 12, an outdoor heat exchanger 13, an outdoor expansion valve 14, a water-refrigerant heat exchanger 15, an accumulator 16, and an outdoor blower 17. These components—the compressor 11, the four-way valve 12, the outdoor heat exchanger 13, the outdoor expansion valve 14, the water-refrigerant heat exchanger 15, and the accumulator 16—are connected by refrigerant piping 18 to form a refrigerant circuit 10 through which the refrigerant circulates. This refrigerant circuit 10 is completed within the outdoor unit 2 and constitutes a refrigeration cycle. A flammable refrigerant with a low Global Warming Potential (GWP), such as propane (R290), is used as the refrigerant circulating in the refrigerant circuit 10. In addition, a water pipe 19 is connected to the water-refrigerant heat exchanger 15 separately from the refrigerant piping 18. This water pipe 19 extends to the outside of the outdoor unit 2 and is connected to the indoor heat exchanger 23 of the indoor unit 3 (described later) to form a water circuit 4.

[0013] The compressor 11 is, for example, a high-pressure vessel type variable-capacity compressor whose operating capacity can be changed, and it compresses the inhaled low-pressure gaseous refrigerant to discharge high-pressure gaseous refrigerant. A four-way valve 12 is connected to the refrigerant discharge side of the compressor 11, and an accumulator 16 is connected to the refrigerant suction side. The four-way valve 12 is a valve for switching the direction of refrigerant flow in the refrigerant circuit 10, and has a first port 12A to a fourth port 12D. The first port 12A is connected to the refrigerant discharge side of the compressor 11. The second port 12B is connected to one of the refrigerant inlets and outlets 13A of the outdoor heat exchanger 13. The third port 12C is connected to the refrigerant inlet side of the accumulator 16. And the fourth port 12D is connected to one of the refrigerant inlets and outlets 15A of the water refrigerant heat exchanger 15.

[0014] The outdoor heat exchanger 13 is, for example, a fin-tube heat exchanger. The outdoor heat exchanger 13 exchanges heat between the flammable refrigerant and the outside air taken into the outdoor unit 2 by the rotation of the outdoor fan 17. The other refrigerant inlet / outlet 13B of the outdoor heat exchanger 13 is connected to the other refrigerant inlet / outlet 15B of the water refrigerant heat exchanger 15 via the outdoor expansion valve 14. When the hot water heating system 1 is in cooling operation, the outdoor heat exchanger 13 functions as a condenser to condense (liquefy) the gaseous refrigerant. Also, when the hot water heating system 1 is in heating operation, the outdoor heat exchanger 13 functions as an evaporator to evaporate (vaporize) the liquid refrigerant. The outdoor expansion valve 14 is provided between the other refrigerant inlet / outlet 13B of the outdoor heat exchanger 13 and the other refrigerant inlet / outlet 15B of the water refrigerant heat exchanger 15. The outdoor expansion valve 14 is, for example, an electronic expansion valve, and by adjusting the valve opening, the liquid refrigerant passing through the outdoor expansion valve 14 is depressurized (expanded).

[0015] The water-refrigerant heat exchanger 15 is, for example, a plate heat exchanger. The water-refrigerant heat exchanger 15 exchanges heat between the flammable refrigerant circulating in the refrigerant circuit 10 and the water circulating in the water circuit 4. When the hot water heating system 1 is performing cooling or defrosting operations, the water-refrigerant heat exchanger 15 functions as an evaporator to evaporate (vaporize) the liquid refrigerant. Also, when the hot water heating system 1 is performing heating operations, the water-refrigerant heat exchanger 15 functions as a condenser to condense (liquefy) the gaseous refrigerant. The water-refrigerant heat exchanger 15 has a water inlet 15C and a water outlet 15D, and water pipes 19 are connected to these water inlet 15C and water outlet 15D respectively, forming part of the water circuit 4. In addition, for example, a circulation pump 21 for circulating water in the water circuit 4 is provided on the water inlet 15C side, and an air vent valve 22 for removing air that has entered the water circuit 4 is provided on the water outlet 15D side.

[0016] The refrigerant inlet side of the accumulator 16 is connected to the third port 12C of the four-way valve 12, and the refrigerant outlet side is connected to the refrigerant inlet side of the compressor 11. The accumulator 16 is formed as a hollow pressure vessel and separates the refrigerant flowing into it into gaseous refrigerant and liquid refrigerant, allowing only the gaseous refrigerant to be drawn into the compressor 11. The outdoor blower 17 is positioned near the outdoor heat exchanger 13 and passes air through the outdoor heat exchanger 13. Specifically, the outdoor blower 17 draws outside air into the outdoor unit 2 from the intake port 52 and intake opening 51 of the outdoor unit 2 (described later), and releases the outside air that has exchanged heat with the refrigerant in the outdoor heat exchanger 13 to the outside of the outdoor unit 2 from the outlet 50 (described later).

[0017] On the other hand, the indoor unit 3 has an indoor heat exchanger 23. For example, a floor heating system or a radiator can be used as the indoor heat exchanger 23. One refrigerant inlet / outlet 23A of the indoor heat exchanger 23 is connected to the water outlet 15D of the water refrigerant heat exchanger 15. The other refrigerant inlet / outlet 23B of the indoor heat exchanger 23 is connected to the water inlet 15C of the water refrigerant heat exchanger 15 via a circulation pump 21. As a result, the indoor heat exchanger 23 is connected to the water refrigerant heat exchanger 15 by water piping 19 to form a water circuit 4, and the water circulating in this water circuit 4 releases or absorbs heat in the indoor heat exchanger 23, thereby heating or cooling the air-conditioned space in which the indoor unit 3 is installed.

[0018] [Outdoor Unit Structure] Next, the external appearance and internal structure of the outdoor unit 2 will be described. The directions described below, such as front and back, up and down, and left and right, indicate the directions when the outdoor unit 2 is installed on a horizontal mounting surface, with front and back and left and right indicating the horizontal direction. Also, the surfaces described below, such as the front and back, indicate the respective surfaces when the outdoor unit 2 is installed horizontally, with front and back indicating the surfaces viewed from the horizontal direction. As shown in Figures 2 and 3, the outdoor unit 2 is equipped with a rectangular box-shaped housing 30 in which the left-right direction (width direction) dimension is larger than the front-back direction (depth direction). This housing 30 is equipped with a bottom plate 31 positioned opposite the mounting surface, a top panel 32 positioned above the bottom plate 31 in the height direction, and a side panel portion 33 that connects the bottom plate 31 and the top panel 32 and separates the inside and outside of the housing 30.

[0019] As shown in Figure 4, the interior of the housing 30 is divided into a blower room RA on the left side and a machine room RB on the right side by a partition plate 34 fixed to the bottom plate 31. An exhaust port 34a is formed at the bottom of the partition plate 34, connecting the blower room RA and the machine room RB. This exhaust port 34a is made up of a number of small holes. The outdoor heat exchanger 13 is housed on the rear side of the blower room RA, and the outdoor blower 17 is positioned on the front side. The outdoor heat exchanger 13 is formed by bending into an L shape when viewed from above (top panel 32 side), and is supported by the bottom plate 31 along the left side from the rear side of the blower room RA. The outdoor blower 17 corresponds to the blower of the present invention, and the outdoor heat exchanger 13 corresponds to the heat exchanger of the present invention.

[0020] The outdoor fan 17 is attached to a pair of support members 35 erected on the bottom plate 31. The outdoor fan 17 is a so-called axial fan, and driven by the fan motor 17A, it draws outside air into the fan chamber RA from the intake port 52 (described later) formed on the rear side of the outdoor unit 2, i.e., the rear side of the outdoor heat exchanger 13, and from the intake opening 51 (described later) formed on the left side. The air that has undergone heat exchange in the outdoor heat exchanger 13 is then blown out to the front from the outlet 50 formed on the front side of the fan chamber RA. In this way, the outdoor unit 2 is a front-discharge type outdoor unit that blows out the air that has undergone heat exchange from the front side.

[0021] In the lower space of the machine room RB, some of the components of the refrigerant circuit 10 are arranged, including the compressor 11, accumulator 16, four-way valve 12 (see Figure 1), and outdoor expansion valve 14 (see Figure 1). The compressor 11 and accumulator 16 are fixed to the bottom plate 31. Also in the lower space of the machine room RB, some of the components of the water circuit 4 are arranged, including the water-refrigerant heat exchanger 15, air vent valve 22, and circulation pump 21. On the other hand, in the upper space of the machine room RB, multiple refrigerant pipes 18 that connect the components of the refrigerant circuit 10 are arranged. In the upper space of the blower room RA and the machine room RB, an electrical component box 25 is arranged spanning the blower room RA and the machine room RB.

[0022] Next, the side panel section 33 will be described. The side panel section 33 is formed by combining a plurality of panel members. In this embodiment, as shown in Figures 2 and 3, the side panel section 33 comprises a front panel 37, a rear panel 38, a front service panel 39, a left side panel 40, and a right side service panel 41. The side of the left side panel 40 corresponds to the side of the present invention, and the side of the rear panel 38 corresponds to the rear of the present invention. The front panel 37 integrally comprises a first front section 37A that forms a part of the front of the housing 30 and a first left side section 37B that forms a part of the left side of the housing 30. The rear panel 38 integrally comprises a first rear section 38A that forms a part of the back of the housing 30 and a first right side section 38B that forms a part of the right side of the housing 30. The front service panel 39 integrally comprises a second right side section 39A that forms a part of the right side of the housing 30 and a second front section 39B that forms a part of the front of the housing 30. The left side panel 40 integrally comprises a first left side portion 40A that forms a part of the left side of the housing 30 and a second rear portion 40B that forms a part of the rear of the housing 30.

[0023] The first front portion 37A of the front panel 37 is positioned on the front side of the blower room RA, and the second front portion 39B of the front service panel 39 is positioned on the front side of the machine room RB. These first front portion 37A and second front portion 39B are arranged side by side to form the front of the housing 30. An outlet 50 is formed in the first front portion 37A from which air that has undergone heat exchange inside the blower room RA is blown out. The outlet 50 has, for example, a circular bell mouth 41A, and a part of the outdoor blower 17 is positioned within this bell mouth 41A. A mesh fan guard 42 covering the outlet 50 is provided in front of the front panel 37. This fan guard 42 is fixed to the front panel 37 with a predetermined gap between the upper end (upper end) 42A of the fan guard 42 and the top panel 32.

[0024] The first rear portion 38A of the rear panel 38 and the second rear portion 40B of the left side panel 40 are arranged side by side with a gap between them, forming the rear of the housing 30. The outdoor heat exchanger 13 is exposed between the first rear portion 38A and the second rear portion 40B, and this exposed area becomes the intake port 52. The second right side portion 39A of the front service panel 39 and the first right side portion 38B of the rear panel 38 are arranged side by side front to back with a gap between them, forming the right side that connects the front and rear of the housing 30. The right side service panel 41 is detachably positioned between the second right side portion 39A and the first right side portion 38B. The first left side portion 40A of the left side panel 40 and the first left side portion 37B of the front panel 37 are arranged side by side in the front to back direction, forming the left side that connects the front and rear of the housing 30. The first left side portion 40A faces a part of the outdoor heat exchanger 13, and a plurality of intake openings 51 are formed in this first left side portion 40A. As shown in Figure 3, an air intake port 55 is formed at the top of the first rear portion 38A, and a cover 56 is provided on the outside of the first rear portion 38A to prevent rainwater from entering by creating a gap between it and the air intake port 55.

[0025] Next, the electrical component box 25 will be described. As shown in Figure 4, the electrical component box 25 is a rectangular box-shaped body that spans from the blower room RA on the left to the upper space of the machine room RB on the right, and is installed on top of the partition plate 34 and supported by the partition plate 34. The electrical component box 25 comprises an electrical component box body 25A with an open top surface and a lid member 25B that closes the opening of the electrical component box body 25A. The electrical component box body 25A comprises a rectangular main body bottom plate 25Aa, a front side wall 25Ab rising from the front side end of the main body bottom plate 25Aa, a rear side wall 25Ac rising from the rear side end of the main body bottom plate 25Aa, a left side wall 25Ad rising from the left side end of the main body bottom plate 25Aa, and a right side wall 25Ae rising from the right side end of the main body bottom plate 25Aa. The upper ends of the front side wall 25Ab, the rear side wall 25Ac, the left side wall 25Ad, and the right side wall 25Ae are provided with flange portions 24 to which a cover member 25B is attached with screws. In the blower room RA, an L-shaped outdoor heat exchanger 13 is arranged on the rear and left side when viewed from above, and the rear side wall 25Ac and the left side wall 25Ad face this outdoor heat exchanger 13. On the right side (one end) of the rear side wall 25Ac, a rear opening 26 consisting of multiple small holes is formed. The internal space of the electrical equipment box 25 is in communication with the outside air through the rear opening 26, the air intake 55 shown in Figure 3, and the duct 27 connecting the rear opening 26 and the air intake 55. The rear opening 26, the duct 27, and the air intake 55 constitute an air introduction section 57 that allows outside air to flow into the electrical equipment box 25.

[0026] As shown in Figures 4 and 5, a first control board 29A and a second control board 29B are arranged on the main body bottom plate 25Aa of the electrical component box 25. The first control board 29A is located on the left side inside the electrical component box 25, and the second control board 29B is located to the right of the first control board 29A. The first control board 29A is a control board that controls the operation of the compressor 11 and the like. The inverter section 29Aa is provided in the left region of the first control board 29A in Figure 5, and the inverter control section 29Ab is provided in the right region. Note that the first control board 29A corresponds to the control board of the present invention.

[0027] The inverter section 29Aa is equipped with several high-heat-generating electronic components, such as an IPM (Intelligent Power Module), diode bridge, fast-coverage diode, and IGBT (Insulated Gate Bipolar Transistor). The inverter control section 29Ab is equipped with electronic components that generate less heat than those mounted on the inverter section 29Aa, such as a microcontroller and a low-power connector for plugging and unplugging. The second control board 29B is a control board that removes noise from the power supply circuit and controls the components of the refrigerant circuit 10 and the water circuit 4. Similar to the inverter control section 29Ab of the first control board 29A, the second control board 29B is equipped with electronic components that generate less heat than those mounted on the inverter section 29Aa.

[0028] As shown in Figure 5, the first control board 29A is supported by the first board support base 60 and positioned at the left end of the main body bottom plate 25Aa. The second control board 29B is supported by the second board support base 61 and positioned on the main body bottom plate 25Aa to the right of the first control board 29. Figure 6 is a view taken along line A-A in Figure 5. A heat sink 62 is positioned at the bottom left of the first board support base 60. A sink opening 25Af is formed in the main body bottom plate 25Aa at the left end of the electrical component box 25. The heat sink 62 consists of a plate-shaped heat sink body 62a and a plurality of fins 62b that are integrally formed with the heat sink body 62a and protrude parallel to each other. The fins 62b that pass through the sink opening 25Af in the main body bottom plate 25Aa are positioned in the blower chamber RA, and the heat sink body 62a is in close contact with the lower surface of the inverter section 29Aa of the first control board 29A via a highly thermally conductive coating material (e.g., silicone grease). As a result, the inverter section 29Aa and the heat sink 62 are thermally coupled. Here, as shown in Figures 5 and 6, the outdoor heat exchanger 13 has a left side surface 13a and a rear surface 13b, and the fins 62b face both the left side surface 13a and the rear surface 13b.

[0029] On the right side of the first substrate support base 60, a predetermined gap is provided between the lower surface of the inverter control unit 29Ab of the first control board 29A and the main body bottom plate 25Aa, thereby forming a space 60a below the inverter control unit 29Ab. The main body bottom plate 25Aa has a first opening 63 formed in the position below the inverter control unit 29Ab where the space 60a is provided, consisting of a plurality of small holes and extending in the front-rear direction. As shown in Figure 7, a first flow path member 64 and a second flow path member 65 are arranged on the outside of the electrical component box body 25A, and an air outlet section 66 is arranged formed by these first flow path member 64 and second flow path member 65, with the first opening 63 as the air inlet.

[0030] As shown in Figure 6, a first flow path 66a communicating with the first opening 63 is formed by providing a predetermined gap between the first flow path plate 64a of the first flow path member 64 and the main body bottom plate 25Aa. A second flow path 66b is formed by providing a predetermined gap between the first flow path plate 64a of the first flow path member 64 and the second flow path plate 65a of the second flow path member 65. An intermediate opening 64b is formed on the right side of the first flow path plate 64a of the first flow path member 64, connecting the first flow path 66a and the second flow path 66b. A second opening 67 is formed at the left end of the second flow path plate 65a of the second flow path member 65, consisting of a plurality of small holes that connect the second flow path 66b and the blower chamber RA, and extending in the front-rear direction. As a result, the air outlet section 66 is composed of a first opening 63, a first flow path 66a, an intermediate opening 64b, a second flow path 66b, and a second opening 67, connecting the inside of the electrical component box 25 to the blower room RA. The first flow path 66a, the intermediate opening 64b, and the second flow path 66b correspond to the flow paths of the present invention.

[0031] On the other hand, the second control board 29B, which supports the second control board 29B, is located on the main body bottom plate 25Aa to the right of the first control board 29, without the aforementioned heat sink 62 or air outlet 66. Here, as shown in Figure 8, if H is the vertical distance between the center of the rotation axis 17a of the outdoor fan 17 and the lower end of the air outlet 66 (the lower surface of the second flow path member 65), and R is the radius of the rotation trajectory of the outdoor fan 17, then the relationship 1.05 ≤ H / R < 1.30 exists. Also, if L is the horizontal distance between the second opening 67 of the air outlet 66 and the center of the rotation axis 17a, then the radius R of the rotation trajectory of the outdoor fan 17 has the relationship R / L > 3.

[0032] [Operation] Next, the flow of refrigerant and water during operation of the hot water heating system 1 will be explained. In Figure 1, the dashed arrows indicate the flow of refrigerant during heating operation, and the solid arrows indicate the flow of refrigerant during cooling operation. When the hot water heating system 1 performs heating operation, the four-way valve 12 is switched so that the first port 12A and the fourth port 12D are in communication, and the second port 12B and the third port 12C are in communication, resulting in the communication state shown by the dashed line in Figure 1. As a result, the refrigerant circuit 10 becomes a heating cycle in which the water-refrigerant heat exchanger 15 functions as a condenser and the outdoor heat exchanger 13 functions as an evaporator.

[0033] When the compressor 11 is driven in the state described above for the refrigerant circuit 10, the flammable refrigerant discharged from the compressor 11 flows into the four-way valve 12, and from the four-way valve 12 flows into the water refrigerant heat exchanger 15. The high-temperature gaseous refrigerant that flows into the water refrigerant heat exchanger 15 condenses by exchanging heat with the water circulating in the water circuit 4 of the water refrigerant heat exchanger 15 due to the operation of the circulation pump 21. Meanwhile, the water circulating in the water circuit 4 is heated by the flammable refrigerant in the water refrigerant heat exchanger 15 and becomes hot water. This hot water flows into the indoor heat exchanger 23 of the indoor unit 3 through the water piping 19 of the water circuit 4. Then, the hot water releases heat in the indoor heat exchanger 23, heating the room in which the indoor unit 3 is installed.

[0034] The liquid phase of the flammable refrigerant, which has condensed through heat exchange with water in the water refrigerant heat exchanger 15, passes through the outdoor expansion valve 14, is depressurized, and then flows into the outdoor heat exchanger 13. The flammable refrigerant that has flowed into the outdoor heat exchanger 13 evaporates through heat exchange with the outside air that has flowed into the outdoor unit 2 due to the rotation of the outdoor fan 17. The gaseous phase of the flammable refrigerant evaporated in the outdoor heat exchanger 13 passes through the four-way valve 12 and the accumulator 16 in that order, is drawn into the compressor 11, and is compressed again. Furthermore, when the hot water heating system 1 is performing cooling or defrosting operations, the four-way valve 12 is switched so that the first port 12A and the second port 12B are in communication, and the third port 12C and the fourth port 12D are in communication, resulting in the communication state shown by the solid line in Figure 1. As a result, the refrigerant circuit 10 becomes a cooling cycle in which the water refrigerant heat exchanger 15 functions as an evaporator and the outdoor heat exchanger 13 functions as a condenser.

[0035] When the compressor 11 is driven in the state described above in the refrigerant circuit 10, the flammable refrigerant discharged from the compressor 11 flows into the four-way valve 12 and then into the outdoor heat exchanger 13. The high-temperature gaseous flammable refrigerant that flows into the outdoor heat exchanger 13 condenses by exchanging heat with the outdoor air taken into the outdoor unit 2 by the rotation of the outdoor fan 17. If defrosting is being performed, the outdoor fan 17 is stopped, and the frost generated in the outdoor heat exchanger 13 melts due to the heat of the refrigerant flowing into the outdoor heat exchanger 13.

[0036] The liquid phase of the flammable refrigerant condensed in the outdoor heat exchanger 13 is depressurized by the outdoor expansion valve 14 and then flows into the water refrigerant heat exchanger 15. The liquid phase of the flammable refrigerant that flows into the water refrigerant heat exchanger 15 evaporates by exchanging heat with the water circulating in the water circuit 4 of the water refrigerant heat exchanger 15 through the operation of the circulation pump 21. Meanwhile, the water circulating in the water circuit 4 is cooled by the flammable refrigerant in the water refrigerant heat exchanger 15 and becomes chilled water. This chilled water flows into the indoor heat exchanger 23 of the indoor unit 3 through the water pipe 19 of the water circuit 4. Then, the chilled water in the indoor heat exchanger 23 absorbs heat from the indoor air, thereby cooling the room in which the indoor unit 3 is installed. When defrosting is being performed, the circulation pump 21 is stopped to stop the circulation of water in the water circuit 4 in order to suppress the decrease in indoor temperature. The flammable refrigerant in the gas phase, evaporated in the water refrigerant heat exchanger 15, passes through the four-way valve 12 and the accumulator 16 in that order, and is drawn into the compressor 11 where it is compressed again.

[0037] Next, the cooling of the first control board 29A and the second control board 29B housed in the electrical equipment box 25 will be described. When the outdoor blower 17 is driven, an airflow is generated in the blower room RA where outside air drawn in from the intake opening 51 and intake port 52 passes through the outdoor heat exchanger 13 and flows toward the outlet 50. An air outlet 66 is located in this airflow in the blower room RA, and a suction force toward the blower room RA is generated at the second opening 67 of the air outlet 66, which is provided on the second flow plate 65a of the second flow channel member 65 that forms the surface along which the airflow follows.

[0038] When a suction force toward the blower room RA is generated at the second opening 67 of the air outlet 66, outside air is drawn into the electrical component box 25 from the air inlet 57. The outside air drawn into the electrical component box 25 flows from right to left inside the electrical component box 25, and cools the electronic components mounted on the second control board 29B by coming into contact with them. The air that has cooled the electronic components of the second control board 29B and flowed to the left then flows into the space 60a provided below the inverter control unit 29Ab of the control board 29A, which is supported by the first board support base 60.

[0039] The air flowing into the space 60a below the inverter control unit 29Ab cools the electronic components mounted on the inverter control unit 29Ab. As shown in Figure 6, the air flowing into space 60a passes through the first opening 63, flows to the right in the first flow path 66a, passes through the intermediate opening 64b, flows to the left in the second flow path 66b, and is discharged into the blower room RA from the second opening 67.

[0040] On the other hand, the inverter section 29Aa of the first control board 29A is thermally coupled to the heat sink 62, and the fins 62b of the heat sink 62 are positioned facing the left side portion 13a and the rear portion 13b of the outdoor heat exchanger 13. As a result, outside air drawn in from the intake opening 51 and intake port 52 passes through the left side portion 13a and the rear portion 13b of the outdoor heat exchanger 13 and comes into contact with the fins 62b. Therefore, the heat-generating electronic components mounted on the inverter section 29Aa are cooled via the heat sink 62.

[0041] Here, if H is the vertical distance between the center of the rotation axis 17a of the outdoor fan 17 and the lower end of the air outlet 66, and R is the radius of the rotation trajectory of the outdoor fan 17, then the relationship 1.05 ≤ H / R < 1.30 exists, so that no noise is generated when air is drawn in at the second opening 67, and a sufficient airflow rate can be secured to cool the electronic components mounted on the first control board 29A and the second control board 29B. If the value of H / R is less than 1.05, the distance between the outdoor fan 17 and the lower end of the air outlet 66 becomes too close, and noise may be generated at the second opening 67. On the other hand, if the value of H / R is 1.30 or more, the distance between the outdoor fan 17 and the second opening 67 becomes too far, the pressure at the second opening 67 does not decrease, and the airflow rate inside the electrical component box 25 may decrease.

[0042] Furthermore, if L is the left-right distance between the second opening 67 of the air outlet 66 and the center of the rotation axis 17a, and R is the radius of the rotation trajectory of the outdoor blower 17, then the relationship R / L > 3 holds, so the pressure at the first opening 63 decreases, which can increase the airflow rate inside the electrical equipment box 25. However, if the value of R / L is 3 or less, the second opening 67 is positioned far from the outdoor blower 17, so the pressure at the second opening 67 does not decrease, and there is a risk that the airflow rate inside the electrical equipment box 25 will decrease.

[0043] Next, we will explain the operation when flammable refrigerant leaks from a component of the refrigerant circuit 10 located in the machine room RA. When the outdoor blower 17 is driven, an airflow is generated in the blower room RA from the intake opening 51 and intake port 52 toward the outlet port 50, generating a suction force toward the blower room RA at the exhaust port 34a formed at the bottom of the partition plate 34. When flammable refrigerant leaks from a component of the refrigerant circuit 10 located in the machine room RA (for example, refrigerant piping 18), the flammable refrigerant is generally denser than air and accumulates at the bottom of the machine room RB. At this time, the flammable refrigerant accumulated at the bottom of the machine room RB flows from the exhaust port 34a of the partition plate 34 into the blower room RA and is discharged to the outside of the housing 30. This prevents the flammable refrigerant from entering the inside of the electrical equipment box 25. Furthermore, if a spark occurs in the electronic components housed in the electrical equipment box 25, the ignition of the flammable refrigerant is prevented, thus ensuring safety.

[0044] [Effect] Next, the effect of the hot water heating apparatus 1, which is an example of the above-described heat pump apparatus, will be described. In the hot water heating apparatus 1 according to the present embodiment, the interior of the housing 30 is partitioned by a partition plate 34 into a blower chamber RA and a machine chamber RB. The outdoor blower 17 and the outdoor heat exchanger 13 are arranged in the blower chamber RA, the compressor 11 and the refrigerant pipe 18 constituting a part of the refrigerant circuit 10 are arranged in the machine chamber RB, and the electrical component box 25 accommodating control boards 29A and 29B is at least partially arranged at the upper part of the blower chamber RA. The electrical component box 25 comprises: an air introduction part 57 that allows air outside the housing 30 to flow into the electrical component box 25 without passing through the machine chamber RB by driving of the outdoor blower 17; and an air outflow part 66 that allows air that has flowed inside the electrical component box 25 to flow out. The air outflow part 66 is arranged on a surface along which the air drawn in by driving of the outdoor blower 17 and passing through the outdoor heat exchanger 13 flows. According to this configuration, the air introduction part 57 that takes in air outside the housing 30 is provided, and the space through which the external air flows is blocked from the machine chamber RB, so that flammable refrigerant leaked in the machine chamber RB can be prevented from infiltrating into the interior of the electrical component box 25, thereby ensuring safety. In addition, since the air outflow part 66 is arranged on the surface along which the air drawn in by driving of the outdoor blower 17 and passing through the outdoor heat exchanger 13 flows, the suction force generated at the second opening 67 of the air outflow part 66 increases the flow rate of air passing through the interior of the electrical component box 25, thereby reliably cooling the heat-generating electronic components mounted on the first control board 29A and the second control board 29B, and preventing deterioration and failure of the electronic components.

[0045] Furthermore, in the hot water heating device 1 according to this embodiment, the air outlet 66 is positioned above the outdoor fan 17. With this configuration, since the second opening 67 of the air outlet 66 is located near the outdoor fan 17, the pressure near the second opening 67 is reduced, and the suction force can be further increased. In addition, in the hot water heating device 1 according to this embodiment, when H is the height distance between the center of the rotation axis 17a of the outdoor fan 17, which extends in the front-rear direction of the housing 30, and the air outlet 66, and R is the radius of the rotation trajectory of the outdoor fan 17, the relationship 1.05 ≤ H / R < 1.30 is met. With this configuration, noise is not generated when air is drawn in at the second opening 67 of the air outlet 66, and a sufficient airflow rate can be secured to cool the electronic components mounted on the first control board 29A and the second control board 29B.

[0046] Furthermore, in the hot water heating device 1 according to this embodiment, the air outlet 66 has a flow path (first flow path 66a, intermediate opening 64b, and second flow path 66b) that connects the inside and outside of the electrical equipment box 25. If R is the radius of the rotation trajectory of the outdoor blower 17, and L is the distance in the left-right direction of the housing 30 between the second opening 67, which is one end of the flow path formed on the outside of the electrical equipment box 25, and the center of the rotation axis 17a, then the relationship R / L > 3 exists. With this configuration, the pressure at the second opening 67 is reduced, so the airflow rate inside the electrical equipment box 25 can be further increased.

[0047] Furthermore, in the hot water heating apparatus 1 according to the present embodiment, the air outflow portion 66 includes a first opening 63 formed in a main body bottom plate 25Aa of an electrical component box 25, a flow path (a first flow path 66a, an intermediate opening 64b, and a second flow path 66b) having one end connected to the first opening 63, and a second opening 67 connected to the other end of the flow path at a position below the first opening 63. The flow path sequentially extends from the first opening 63 in a first direction (rightward direction) on a plane orthogonal to the vertical direction, downward, and a second direction (leftward direction) on the plane, and is connected to the second opening 67. According to this configuration, by providing the flow path extending in the first direction and the second direction, moisture and combustible refrigerant are less likely to enter from the lower second opening toward the upper first opening. Thereby, moisture does not come into contact with the control boards 29A and 29B, and problems such as a short circuit can be prevented. Further, since infiltration of combustible refrigerant into the interior of the electrical component box 25 is prevented, ignition of the combustible refrigerant when sparking occurs in electronic components is prevented, and safety can be ensured. Furthermore, according to this arrangement, although resistance is caused to air passing through the flow path, since the air outflow portion 66 is arranged on a surface along which the flow of air drawn in by driving the outdoor blower 17 and passing through the outdoor heat exchanger 13 runs, a sufficient flow rate of air flowing into the first opening 63 can be secured.

[0048] Furthermore, in the hot water heating apparatus 1 according to the present embodiment, the air outflow portion 66 includes the first opening 63 formed in the main body bottom plate 25Aa of the electrical component box 25, and an inverter control portion 29Ab of the first control board 29A is arranged at a position overlapping the first opening 63 in the vertical direction with a predetermined gap provided between the inverter control portion 29Ab and the main body bottom plate 25Aa. According to this configuration, the arrangement space for the first control board 29A inside the electrical component box 25 can be effectively utilized. According to this arrangement, although resistance is caused to air passing through the flow path, since the air outflow portion 66 is arranged on a surface along which the flow of air drawn in by driving the outdoor blower 17 and passing through the outdoor heat exchanger 13 runs, a sufficient flow rate of air flowing into the first opening 63 can be secured.

[0049] Furthermore, in the hot water heating device 1 according to this embodiment, the air intake section 57 of the electrical components box 25 is located on the right side of the housing 30, and the inverter section 29Aa that drives the compressor is mounted on the first control board 29A. The first control board 29A is housed in the electrical components box 25 such that at least a part of the inverter section 29Aa is located to the left of the air outlet section 66, and a heat sink 62 thermally coupled to the inverter section 29Aa is located outside the electrical components box 25 to the left of the air outlet section 66. With this configuration, relatively small heat-generating electronic components mounted on the inverter control section 29Ab and the second control board 29B are cooled by the air passing through the inside of the electrical components box 25, while large heat-generating electronic components mounted on the inverter section 29Aa are cooled by the heat sink 62 thermally coupled to the inverter section 29Aa. In this way, by efficiently cooling the heat-generating electronic components with the heat sink 62, it is possible to place relatively low-heat-generating electronic components in the limited space from the rear opening 26 to the first opening 63, which is the area through which air passes inside the electrical component box 25.

[0050] Furthermore, in the hot water heating system 1 according to this embodiment, the blower room RA is located on the left side of the housing 30, the machine room RB is located on the right side of the housing 30, and the left side portion 13a and rear portion 13b of the outdoor heat exchanger 13 are positioned opposite the rear and left side of the electrical components box 25 where the first control board 29A is housed. With this configuration, outside air passing through the left side portion 13a and rear portion 13b comes into contact with the fins 62b of the heat sink 62, which is thermally coupled to the inverter portion 29Aa of the first control board 29A. Therefore, the heat-generating electronic components mounted on the inverter portion 29Aa can be efficiently cooled by the heat sink 62 without being cooled by the air passing through the inside of the electrical components box 25.

[0051] The above describes a hot water heating system 1, which is an example of a heat pump system according to the present invention. However, the heat pump system is not limited to the hot water heating system 1, and may also be an air conditioner as a heat pump system.

[0052] 1 Hot water heating system 2 Outdoor unit 3 Indoor unit 4 Water circuit 10 Refrigerant circuit 11 Compressor 12 Four-way valve 12A-12D First port to fourth port 13 Outdoor heat exchanger 13a Left side of outdoor heat exchanger 13b Rear of outdoor heat exchanger 13A Refrigerant inlet / outlet 13B Refrigerant inlet / outlet 14 Outdoor expansion valve 15 Water-refrigerant heat exchanger 15A Refrigerant inlet / outlet 15B Refrigerant inlet / outlet 15C Water inlet 15D Water outlet 16 Accumulator 17 Outdoor fan 17a Rotating shaft 18 Refrigerant piping 21 Circulation pump 22 Air vent valve 23 Indoor heat exchanger 24 Flange section 25 Electrical component box 25A Electrical component box body 25Aa Bottom plate of main body 25Ab Front side wall 25Ac Rear side wall 25Ad Left side wall 25Ae Right side wall 25Af Sink opening 25B Cover member 26 Rear opening 27 Duct 27a Duct bottom 29A First control board 29Aa Inverter unit 29Ab Inverter control unit 29B Second control board 30 Housing 31 Bottom plate 32 Top panel 33 Side panel 34 Partition plate 34a Exhaust port 35 Support member 37 Front panel 37A First front section 37B First left side section 38 Rear panel 38A First rear section 38B First right side section 39 Front service panel 39A Second right side section 39B Second front section 40 Left side panel 40A First left side section 40B Second rear section 41 Right side service panel 41A Bell mouth 42 Fan guard 50 Air outlet 51 Intake opening 52 Intake port 55 Air intake port 56 Cover 57 Air introduction section 60 First substrate support base 60a Space 61 Second substrate support base 62 Heat sink 62a Heat sink body 62b Fin 63 First opening 64 First flow path member 64a First flow path plate 64b Intermediate opening 65 Second flow path member 65a Second flow path plate 66 Air outlet section 66a First flow path 66b Second flow path 67 Second opening RA Blower room RB Machine room

Claims

1. A heat pump device comprising: a compressor forming a refrigerant circuit through which a flammable refrigerant circulates, a heat exchanger, a blower for circulating air to the heat exchanger, a control board for controlling the compressor and the blower, and an electrical component box housing the control board, wherein the interior of the enclosure is divided into a blower room and a machine room by a partition plate, the blower and the heat exchanger are arranged in the blower room, the compressor and at least a part of the refrigerant circuit are arranged in the machine room, at least a part of the electrical component box is located above the blower room, the electrical component box comprises an air inlet for drawing in air from outside the enclosure without passing through the machine room by the drive of the blower, and an air outlet for releasing the air that has flowed inside the electrical component box, and the air outlet is located on the surface along which the airflow drawn in by the drive of the blower and passing through the heat exchanger follows.

2. The heat pump device according to claim 1, characterized in that the air outlet is located above the blower.

3. The heat pump device according to claim 2, characterized in that when H is the height distance between the center of the rotation axis of the blower extending in the front-rear direction of the housing and the air outlet, and R is the radius of the rotation trajectory of the blower, the following relationship (1) is obtained: 1.05 ≤ H / R < 1.30 ……(1) 4. The heat pump device according to claim 2, characterized in that the air outlet has a flow path that connects the inside and outside of the electrical component box, and the radius of the rotating blades of the blower is R, and the distance in the left-right direction of the housing between the opening of the flow path formed on the outside of the electrical component box and the center of the rotating shaft of the blower is L, such that the following relationship (2) is observed: R / L > 3 ……(2) 5. The heat pump device according to claim 1 or 2, wherein the air outlet comprises a first opening formed in the bottom plate of the electrical equipment box, a flow path one end of which is connected to the first opening, and a second opening located below the first opening and connected to the other end of the flow path, the flow path extending sequentially from the first opening in a first direction, downward, and second direction on a plane perpendicular to the vertical direction, and connected to the second opening.

6. The heat pump device according to claim 1 or 2, characterized in that the air outlet section has a first opening formed in the bottom plate of the electrical component box, and the control board is positioned to overlap the first opening in the vertical direction with a predetermined distance between it and the bottom plate of the electrical component box.

7. The heat pump device according to claim 1 or 2, characterized in that the air intake of the electrical component box is located on one end of the housing in the left-right direction, an inverter unit for driving the compressor is mounted on the control board, the control board is housed in the electrical component box such that at least a part of the inverter unit is located on the other end of the air outlet, and a heat sink thermally coupled to the inverter unit is arranged outside the electrical component box on the other end of the air outlet.

8. The heat pump device according to claim 7, characterized in that the blower room and the machine room are arranged in the left-right direction of the housing, one end of which is the machine room side and the other end of which is the blower room side, and the heat exchanger is arranged to face the rear and side of the other end of the electrical equipment box.

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