Heat pump device

Abstract

This heat pump device includes a housing (30) and a refrigerant circuit (10) through which a flammable refrigerant circulates, wherein: a compressor (11), a heat exchanger (13), a blower (17) that circulates air through the heat exchanger, control boards (29A), (29B) that control the compressor and the blower, and an electrical component box (25) that houses the control boards are provided inside the housing; the inside of the housing is partitioned into a blower chamber (RA) and a machine chamber (RB) by means of a partition plate (34); the blower and the heat exchanger are disposed in the blower chamber; the compressor and piping (18) constituting a part of the refrigerant circuit are disposed in the machine chamber, and the electrical component box is disposed above the compressor and the piping; a first opening portion (61) providing communication between the blower chamber and the machine chamber is formed in an upper part of the partition plate in a position below the electrical component box; and a second opening portion (60) providing communication between the blower chamber and the machine chamber is formed in a lower part of the partition plate.

Description

Heat Pump Apparatus

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

[0002] As a heat pump apparatus using a flammable refrigerant having a low global warming potential (GWP), for example, the refrigeration cycle apparatus disclosed in Patent Document 1 is known. In the refrigeration cycle apparatus of Patent Document 1, the interior of the casing forming the outer shell of the outdoor unit is partitioned into a blower chamber and a machine chamber by a partition plate. A heat exchanger and a blower are arranged in the blower chamber, and a compressor, a refrigerant circuit, an electrical component box, and the like are arranged in the machine chamber. A lower ventilation hole and an upper ventilation hole that communicate the blower chamber and the machine chamber are formed at the lower part and the upper part of the partition plate, respectively.

[0003] The electrical component box is a box that houses a substrate on which electronic components are mounted. An air inlet is formed on one of a pair of mutually opposing side walls, and an air outlet is formed on the other. The electrical component box is arranged at the upper part of the machine chamber in a state where the air inlet is close to an air introduction port formed in the casing, and the air outlet faces the upper ventilation passage of the partition plate. When the blower is driven, a suction force directed toward the blower chamber is generated at the upper ventilation hole of the partition plate, so outside air introduced from the air introduction port of the casing flows through the air inlet of the electrical component box, the air outlet, and the upper ventilation hole into the blower chamber. Thereby, the air flowing inside the electrical component box cools the heat-generating electronic components.

[0004] When flammable refrigerant leaks from the refrigerant circuit in the machine chamber, the flammable refrigerant, which generally has a higher density than air, accumulates in the lower part of the machine chamber. When the blower is driven, a suction force directed toward the blower chamber is generated at the lower ventilation hole of the partition plate, so the flammable refrigerant accumulated in the lower part of the machine chamber flows from the lower ventilation hole into the blower chamber and is forcibly discharged to the outside.

[0005] Japanese Unexamined Patent Publication No. 2015-215162

[0006] Incidentally, depending on the amount and location of the flammable refrigerant leak, it may be difficult to discharge all of the flammable refrigerant accumulated in the machine room through the ventilation holes at the bottom of the partition plate. Therefore, if the flammable refrigerant accumulated in the machine room enters the inside of the electrical component box through the air intake along with the outside air, there is a risk that the flammable refrigerant may ignite if sparks occur in the electronic components.

[0007] Therefore, the present invention has been made to solve these problems and aims to provide a heat pump device that can ensure safety by preventing flammable refrigerant leaked in the machine room from entering the electrical equipment box.

[0008] One aspect of the present invention comprises a housing and a refrigerant circuit through which a flammable refrigerant circulates, wherein a compressor, a heat exchanger, a blower for circulating air to the heat exchanger, a control board for controlling the compressor and blower, and an electrical component box for housing the control board are provided inside the housing, the inside of which is divided into a blower room and a machine room by a partition plate, the blower and heat exchanger are arranged in the blower room, the compressor and piping constituting part of the refrigerant circuit are arranged in the machine room, and the electrical component box is arranged above the compressor and piping, a first opening connecting the blower room and the machine room is formed at the top of the partition plate and below the electrical component box, and a second opening connecting the blower room and the machine room is formed at the bottom of the partition plate.

[0009] The heat pump device of the present invention can prevent flammable refrigerant leaking in the machine room from entering the electrical component box, thereby ensuring safety.

[0010] 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 perspective view of the internal structure of the outdoor unit of the hot water heating system from diagonally below the front. This is a diagram showing the internal structure of the outdoor unit of the hot water heating system from the right. This is a diagram showing the internal structure of the outdoor unit of the hot water heating system from above. This is a diagram showing a second opening formed in the partition plate that separates the blower room and the machine room of the outdoor unit of the hot water heating system. (a) shows an elastic membrane with a straight slit formed in the second opening formed in the partition plate, and (b) shows an electric wire passed through the second opening.

[0011] 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.

[0012] [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, which includes 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.

[0013] 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.

[0014] 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.

[0015] 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 air conditioner 1 is in cooling operation, the outdoor heat exchanger 13 functions as a condenser to condense (liquefy) the gaseous refrigerant. Also, when the air conditioner 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).

[0016] 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 air conditioner 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 air conditioner 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.

[0017] 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 that flows 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 creates airflow. Specifically, the outdoor blower 17 draws outside air into the outdoor unit 2 through 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 through the outlet 50 (described later).

[0018] On the other hand, the indoor unit 3 has an indoor heat exchanger 23. The indoor heat exchanger 23 can be, for example, a floor heating system or a radiator. 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.

[0019] [Outdoor Unit Structure] Next, the external appearance and internal structure of the outdoor unit 2 will be described. Note that the directions such as front / back, up / down and left / right described below refer to the direction in which air is blown out from the air outlet 50 (described later) when the outdoor unit 2 is installed, and the front is defined as the direction when the outdoor unit 2 is viewed from the front. 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 dimension (width direction) is larger than the front-back dimension (depth direction). This housing 30 is equipped with a bottom plate 31 positioned opposite the installation surface, a top panel 32 positioned above the bottom plate 31 in the height direction, and a side panel section 33 that connects the bottom plate 31 and the top panel 32 and separates the inside from the outside of the housing 30.

[0020] As shown in Figure 4, the interior of the housing 30 is divided into a blower room RA and a machine room RB by a partition plate 34 fixed to the bottom plate 31. The blower room RA houses the outdoor heat exchanger 13 at the rear and the outdoor blower 17 at the front. 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 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.

[0021] The outdoor fan 17 is attached to a pair of support members 35, 35 erected on the bottom plate 31. The outdoor fan 17 is a so-called axial flow fan, and when the fan motor 17A is driven, it draws outside air into the fan chamber RA from the rear side of the outdoor unit 2, i.e., from the intake port 44 formed on the rear side of the outdoor heat exchanger 13 and from the intake opening 51 formed on the left side, both of which will be described later. The air that has undergone heat exchange in the outdoor heat exchanger 13 is then blown forward 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.

[0022] In the lower space of the machine room RB, some of the components that make up the refrigerant circuit 10 are arranged, including a compressor 11, an accumulator 16, a four-way valve 12 (see Figure 1), and an outdoor expansion valve 14 (see Figure 1). The compressor 11 and the accumulator 16 are fixed to the bottom plate 31. Also in the lower space of the machine room RB, some of the components that make up the water circuit 4 are arranged, including a water-refrigerant heat exchanger 15, an air vent valve 22 (see Figure 1), and a circulation pump 21 (see Figure 1). On the other hand, in the upper space of the machine room RB, multiple refrigerant pipes 18 that connect the components that make up the refrigerant circuit 10 are arranged. Furthermore, 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. Note that the piping described in the present invention corresponds to the refrigerant pipes 18.

[0023] Next, the side panel section 33 will be described. The side panel section 33 is formed by combining multiple panel members. In this embodiment, as shown in Figures 2 and 3, the side panel section 33 includes a front panel 37, a rear panel 38, a right side panel 39, a left side panel 40, and a service panel 41. 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 rear of the housing 30 and a first right side section 38B that forms a part of the right side of the housing 30. The right side 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.

[0024] The first front portion 37A of the front panel 37 is positioned in front of the blower room RA, and the second front portion 39B of the right side panel 39 is positioned in front of the machine room RB. These first front portion 37A and second front portion 38B 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 36 with a predetermined gap between the upper end (upper end) 42A of the fan guard 42 and the top panel 32.

[0025] 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 air intake 52. An air intake 55 for drawing air (outside air) into the electrical component box 25 is formed at the top of the first rear portion 38A, and a cover 56 that covers the outside air intake 55 is provided on the outer surface of the first rear portion 38A. In this state, an open opening 56A is formed at the bottom of the cover 56, and this opening 56A is in communication with the air intake 55.

[0026] The second right side portion 39A of the right side panel 39 and the first right side portion 38B of the rear panel 38 are arranged side by side with a gap between them, forming the right side that connects the front and rear of the housing 30. A service panel 41 is detachably positioned between these second right side portion 39A and first right side portion 38B. The second 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 second left side portion 40A faces a part of the outdoor heat exchanger 13, and a plurality of intake openings 51 are formed in this second left side portion 40A.

[0027] Next, the electrical component box 25 will be described. As shown in Figure 4, the electrical component box 25 spans the upper space of the blower room RA and the machine room RB, is positioned on top of the partition plate 34, and is supported by the partition plate 34. The electrical component box 25 comprises a box-shaped electrical component box body 25A with an open top, and a lid member 25B that closes the opening of the electrical component box body 25A. Note that the lid member 25B is attached to the electrical component box body 25A without any sealing members such as O-rings being attached to the periphery of the opening of the electrical component box body 25A. For this reason, the electrical component box 25 is not a sealed structure. An opening 26 consisting of multiple small holes is formed in the rear side wall of the electrical component box body 25A. This opening 26 and the air intake 55 (see Figure 3) are in communication via a duct 27. As shown in Figure 5, an air outlet 28 is formed at the bottom of the electrical component box body 25A, which connects the internal space of the electrical component box 25 with the blower room RA.

[0028] As shown in Figure 4, the electrical component box 25 houses a first control board 29A and a second control board 29B. The first control board 29A is housed at the left end of the internal space of the electrical component box 25 and is located in the upper space of the blower room RA. The second control board 29B is housed in the internal space to the right of the first control board 26A. The control boards described in the present invention correspond to the first control board 29A and the second control board 29B. The first control board 29A is a control board that controls the operation of the components of the outdoor blower 17 and the refrigerant circuit 10, and the second control board 29B is a water circuit control board that controls the components of the water circuit 4. Multiple electronic components that generate heat during operation are mounted on the first control board 29A and the second control board 29B.

[0029] Next, the partition plate 34 will be described. As shown in Figures 4 and 6, a lower opening 60 is formed at the bottom of the partition plate 34, which communicates with the blower room RA and the machine room RB. This lower opening 60 is composed of a plurality of small-diameter holes and is formed in a position opposite the bottom of the compressor 11. Also, as shown in Figure 6, an upper opening 61 is formed at the top of the partition plate 34, which communicates with the blower room RA and the machine room RB. This upper opening 61 is formed below near the bottom plate 25a of the electrical equipment box 25, and as shown in Figure 7, it communicates with the negative pressure side space NP, which is the rear side of the outdoor blower 17 of the blower room RA, and the machine room RB.

[0030] As shown in Figure 8, the upper opening 61 is provided with an elastic membrane 63 having linear slits 62A and 62B formed in a cross shape. As shown in Figure 6, wiring 64 that supplies power to the blower motor 17A is drawn out from a terminal (not shown) inside the electrical equipment box 25 to the bottom surface of the electrical equipment box 25. As shown in Figure 7, this wiring 64 is passed through the slits 62A and 62B formed in the elastic membrane 63 of the upper opening 61, passes through the negative pressure side space NP of the blower chamber RA, and is connected to the blower motor 17A of the outdoor blower 17. Note that the first opening described in this invention corresponds to the upper opening 61, and the second opening described in this invention corresponds to the lower opening 60.

[0031] Here, as shown in Figures 9(a) and (b), if the length of the slits 62A and 62B is S and the diameter of the wiring 64 is Φ, then the relationship Φ + 10 mm ≤ S ≤ Φ + 20 mm exists. In this embodiment, the elastic membrane 63 has linear slits 62A and 62B formed in a cross shape, but for example, the elastic membrane 63 may have only one linear slit, or it may have two slits formed in a T shape.

[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 from the four-way valve 12 flows 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 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 flammable refrigerant, which has condensed into a liquid phase 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 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 that has 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 and compressed again.

[0037] Next, the cooling of the first control board 29 and the second control board 29 housed in the electrical component box 25 will be described. An opening 26 formed in the rear side wall of the electrical component box body 25A communicates with an air intake 55 formed in the first rear portion 38A of the rear panel 38 via a duct 27. In addition, an air outlet 28 is formed at the bottom of the electrical component box body 25A, which connects the internal space of the electrical component box 25 to the blower room RA. When the outdoor blower 17 is driven, an airflow is generated in the blower room RA in which 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. Due to this airflow in the blower room RA, an attractive force is generated at the air outlet 28 of the electrical component box 25 toward the blower room RA, so that the air inside the electrical component box 25 is discharged from the air outlet 28 toward the blower room RA. As a result, outside air is drawn into the electrical component box 25 through the air intake 55 via the duct 27 and opening 26, and the outside air flowing inside the electrical component box 25 is discharged from the air outlet 28. In this way, outside air drawn in from outside the housing 30 flows inside the electrical component box 25 and is discharged, so the first control board 29 and the second control board 29 housed in the electrical component box 25 are cooled, and the electronic components that generate heat during operation and are mounted on the first control board 29 and the second control board 29 are efficiently cooled.

[0038] Next, we will explain the operation when flammable refrigerant leaks from the components of the refrigerant circuit 1 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 50, generating a suction force toward the blower room RA at the lower opening 60 formed at the bottom of the partition plate 34. When flammable refrigerant leaks from the components of the refrigerant circuit 1 located in the machine room RA, the flammable refrigerant is generally denser than air and accumulates at the bottom of the machine room RB. At this time, because the lower opening 60 is formed at the bottom of the partition plate 34, the flammable refrigerant accumulated at the bottom of the machine room RB flows from the lower opening 60 into the blower room RA and is discharged to the outside of the housing 30.

[0039] Furthermore, 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 50. This generates a suction force toward the blower room RA at the upper opening 61, which is used as a passage for the wiring 64 at the top of the partition plate 34. Therefore, even if the amount of flammable refrigerant leakage is large, or if the leakage is located at the top, and the lower opening 60 alone is insufficient to discharge the flammable refrigerant from the machine room RB, the upper opening 61, which is used as a passage for the wiring 64, is formed at the top of the partition plate 34. This allows the flammable refrigerant to flow from the upper opening 61 into the blower room RA and be discharged to the outside of the housing 30. As a result, the flammable refrigerant leaked in the machine room RB flows from the lower opening 60 and upper opening 61 formed in the partition plate 34 into the blower room RA and is discharged to the outside of the housing 30.

[0040] The electrical component box 25 is not a sealed structure and is positioned across the upper space of the blower room RA and the machine room RB. However, flammable refrigerant leaking from the machine room RB is discharged into the blower room RA through the lower opening 60 and upper opening 61 of the partition plate 34, thus preventing the flammable refrigerant from entering the inside of the electrical component box 25. This prevents the ignition of the flammable refrigerant in the event of a spark occurring in the electronic components housed in the electrical component box 25, thus ensuring safety. Furthermore, since the upper opening 61 communicates with the negative pressure space NP, which is behind the outdoor blower 17 in the blower room RA, and the machine room RB, a large suction force is generated at the upper opening 61 toward the blower room RA. In this way, a large suction force is generated toward the blower room RA at the upper opening 61 which communicates with the negative pressure space NP and the machine room RB, making it possible to discharge the flammable refrigerant accumulated in the machine room RB to the outside of the machine room RB in a short time.

[0041] Furthermore, the upper opening 61 is provided with an elastic membrane 63 having straight slits 62A and 62B formed in a cross shape, and the relationship between the length S of the slits 62A and 62B and the diameter Φ of the wiring 64 is set to Φ + 10 mm ≤ S ≤ Φ + 20 mm. This sets the gap through which air flows between the slits 62A and 62B and the wiring 64 to an appropriate range, and the airflow velocity of the air passing through the upper opening 61 increases, further increasing the suction force toward the blower room RA. Here, for example, if S = Φ + 5 mm, the gap through which air flows between the slits 62A and 62B and the wiring 64 is too small, increasing air resistance, which may reduce the suction force toward the blower room RA. Also, for example, if S = Φ + 30 mm, the opening is too large, reducing the partitioning performance of the partition plate 34, and the gap through which air flows between the slits 62A and 62B and the wiring 64 is too large, reducing the airflow velocity, which may reduce the suction force toward the blower room RA. As a result, by setting the relationship between the length S of the slits 62A and 62B and the diameter Φ of the wiring 64 to Φ + 10 mm ≤ S ≤ Φ + 20 mm, the partitioning performance of the partition plate 34 can be maintained while further increasing the suction force from the upper opening 61 toward the blower room RA, making it possible to efficiently discharge the flammable refrigerant accumulating in the machine room RB to the outside of the machine room RB.

[0042] [Effects] Next, the effects of the hot water heating system 1, which is an example of the heat pump system described above, will be explained. In the hot water heating system 1 according to this embodiment, the inside of the housing 30 is divided into a blower room RA and a machine room RB by a partition plate 34. An outdoor blower 17 and an outdoor heat exchanger 13 are arranged in the blower room RA, and a compressor 11 and refrigerant piping 18 which constitute a part of the refrigerant circuit 10 are arranged in the machine room RB. An electrical equipment box 25 is arranged above the compressor 11 and the refrigerant piping 18. An upper opening 61 connecting the blower room RA and the machine room RB is formed at the top of the partition plate 34 and below the electrical equipment box 25, and a lower opening 60 connecting the blower room RA and the machine room RB is formed at the bottom of the partition plate 34. With this configuration, even if flammable refrigerant leaks from a component of the refrigerant circuit 10 in the machine room RB, the outdoor blower 17 located in the blower room RA is driven, generating a suction force toward the blower room RA at the lower opening 60 and upper opening 61 of the partition plate 34. This suction force toward the blower room RA at the lower opening 60 and upper opening 61 causes the flammable refrigerant leaking in the machine room RB to be discharged to the outside from the blower room RA. Therefore, it is possible to prevent flammable refrigerant from entering the electrical component box 25, and to prevent the ignition of the flammable refrigerant in the event of a spark occurring in the electronic components housed in the electrical component box 25, thereby ensuring safety.

[0043] Furthermore, in the hot water heating apparatus 1 according to the present embodiment, the electrical component box 25 is arranged across the upper space of the blower chamber RA and the machine chamber RB. According to this configuration, the flammable refrigerant leaked in the machine chamber RB is discharged to the blower chamber RA through the lower opening 60 and the upper opening 61 of the partition plate 34, and the intrusion of flammable refrigerant into the interior of the electrical component box 25 is reliably prevented. Therefore, it is not necessary to manufacture the electrical component box 25 into a sealed structure, and the manufacturing cost of the electrical component box 25 can be reduced while improving the heat dissipation performance of the electrical component box 25. Furthermore, in the hot water heating apparatus 1 according to the present embodiment, the upper opening 61 formed at the upper part of the partition plate 34 communicates the negative pressure side space NP, which is the back side of the outdoor blower 17, with the machine chamber RB. According to this configuration, a large suction force is generated at the upper opening 61 communicating with the negative pressure side space NP of the blower chamber RA, so the flammable refrigerant retained in the machine chamber RB can be discharged to the outside of the machine chamber RB in a short time, and safety can be improved.

[0044] Furthermore, in the hot water heating apparatus 1 according to the present embodiment, a wiring 64 connected to the outdoor blower 17 is passed through the upper opening 61. According to this configuration, instead of providing a wiring through hole and a flammable refrigerant discharge port at different positions on the partition plate 34, the upper opening 61 serves as both the wiring through hole and the flammable refrigerant discharge port, so the manufacturing cost can be further reduced. Furthermore, in the hot water heating apparatus 1 according to the present embodiment, the relationship between the length S of the slits 62A, 62B and the diameter Φ of the wiring 64 satisfies S ≥ Φ + 10 mm. According to this configuration, the gap through which air flows between the slits 62A, 62B and the wiring 64 does not become too small to increase air resistance, and there is no risk of reduction in the suction force toward the blower chamber RA. Therefore, the flammable refrigerant retained in the machine chamber RB can be discharged to the outside of the machine chamber RB in a short time, and safety can be improved.

[0045] Furthermore, in the hot water heating device 1 according to this embodiment, the relationship between the length S of the slits 62A and 62B and the diameter Φ of the wiring 64 is set to S ≤ Φ + 20 mm. With this configuration, the gap through which air flows between the slits 62A and 62B and the wiring 64 is not too large, which would reduce the airflow velocity. This prevents a decrease in the suction force toward the blower room RA, allowing flammable refrigerant accumulated in the machine room RB to be discharged to the outside of the machine room RB in a short time, thereby enhancing safety.

[0046] 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.

[0047] 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: 1st port to 4th port 13. 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 blower 17A: Blower motor 18. Refrigerant piping 21. Circulation pump 22. Air vent valve 23. Indoor heat exchanger 25. Electrical component box 25a: Bottom plate of electrical component box 25A: Electrical component box body 25B: Lid member 26. Opening 27. Duct 28. Air outlet 29A: First control board 29B 30 Second control board 31 Housing 31 Bottom plate 32 Top panel 33 Side panel section 34 Partition plate 35 Support member 37 Front panel 37 37A First front section 37B First left side section 38 Rear panel 38 38A First rear section 38B First right side section 39 Right side panel 39 39A Second right side section 39B Second front section 40 Left side panel 40A First left side section 40B Second rear section 41 Service panel 41A Bell mouth 42 Fan guard 50 Air outlet 51 Intake opening 52 Intake port 55 Air intake port 56 Cover 56A Opening 60 Lower opening 61 Upper opening 62A, 62B Slit 63 Elastic membrane 64 Wiring RA Blower room RB Machine room NP: Negative pressure side space; S: Slit length; Φ: Wiring diameter

Claims

1. A heat pump device comprising a housing and a refrigerant circuit through which a flammable refrigerant circulates, wherein a compressor, 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 for housing the control board are provided inside the housing, the inside of the housing 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 piping constituting part of the refrigerant circuit are arranged in the machine room, and the electrical component box is arranged above the compressor and the piping, a first opening connecting the blower room and the machine room is formed at the top of the partition plate and below the electrical component box, and a second opening connecting the blower room and the machine room is formed at the bottom of the partition plate.

2. The heat pump device according to claim 1, characterized in that the electrical equipment box is arranged across the machine room and the blower room.

3. The heat pump device according to claim 1 or 2, characterized in that the first opening connects the negative pressure side space, which is on the rear side of the blower, to the machine room.

4. The heat pump device according to claim 1 or 2, characterized in that wiring connected to the blower is passed through the first opening.

5. The heat pump device according to claim 4, wherein the first opening is provided with an elastic membrane having a linear slit, and the following relationship (1) holds when the length of the slit is S and the outer diameter of the wiring is Φ: S ≥ Φ + 10 mm ……(1) 6. The heat pump device according to claim 5, characterized in that the length S of the slit and the outer diameter Φ of the wiring have the following relationship: S ≤ Φ + 20 mm ……(2)

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