Outdoor unit and method of assembling outdoor unit

Abstract

An outdoor unit includes a casing, a refrigerant pipe, a refrigerant detection sensor, openings that communicate the inside and the outside of the casing, pipe connection parts, a first cover, and a second cover. The refrigerant pipe is disposed in the casing. A refrigerant flows through the refrigerant pipe. The refrigerant detection sensor is disposed in the casing. The openings that communicate the inside and the outside of the casing are formed on a side surface of the casing. The pipe connection parts connect the refrigerant pipe and a connection pipe extending from an indoor unit. The first cover includes a first portion, a second portion, and a coupling portion. The second cover covers the first cover. The coupling portion is disposed between the first portion and the second portion. The first cover covers the openings and the pipe connection parts. The first portion and the second portion of the first cover are openable and closable by relative movement via the coupling portion.

Description

TECHNICAL FIELD

[0001] The present invention relates to an outdoor unit and a method of assembling the outdoor unit.BACKGROUND ART

[0002] WO 2022 / 107220 A1 describes an air conditioner using a flammable or mildly flammable refrigerant.SUMMARY OF THE INVENTION <Technical Problem>

[0003] In recent years, a highly flammable refrigerant that is particularly easily combusted among flammable refrigerants may be used in air conditioners. When a high-concentration highly flammable refrigerant leaks from a refrigerant circuit of an air conditioner, it is required to detect refrigerant leakage with high accuracy.<Solution to Problem>

[0004] An outdoor unit according to a first aspect includes a casing, a refrigerant pipe, a refrigerant detection sensor, openings that communicate the inside and the outside of the casing, pipe connection parts, a first cover, and a second cover. The refrigerant pipe is disposed in the casing. A refrigerant flows through the refrigerant pipe. The refrigerant detection sensor is disposed in the casing. The openings that communicate the inside and the outside of the casing are formed on a side surface of the casing. The pipe connection parts connect the refrigerant pipe and a connection pipe extending from an indoor unit. The first cover includes a first portion, a second portion, and a coupling portion. The coupling portion is disposed between the first portion and the second portion. The first cover covers the openings and the pipe connection parts. The second cover covers the first cover. The first portion and the second portion of the first cover are openable and closable by relative movement via the coupling portion.

[0005] With this outdoor unit, refrigerant leakage can be detected with high accuracy.

[0006] An outdoor unit according to a second aspect is the outdoor unit according to the first aspect, in which the coupling portion is a rotating structure.

[0007] An outdoor unit according to a third aspect is the outdoor unit according to the first or second aspect, in which the pipe connection parts and the side surface of the casing are separated from each other.

[0008] An outdoor unit according to a fourth aspect is the outdoor unit according to any one of the first to third aspects, and further includes a shutoff valve. The shutoff valve opens and closes the refrigerant circuit. The shutoff valve is covered with the first cover.

[0009] An outdoor unit according to a fifth aspect is the outdoor unit according to the fourth aspect and further includes a terminal block. The terminal block is disposed on the side surface of the casing. The terminal block is disposed above the shutoff valve.

[0010] An outdoor unit according to an sixth aspect is the outdoor unit according to the fourth or fifth aspect and further includes a pressure sensor. The pressure sensor is disposed between the shutoff valve and the pipe connection parts.

[0011] An outdoor unit according to a seventh aspect is the outdoor unit according to any one of the first to sixth aspects, in which the first cover includes a reinforcing member extending so as to cross the inner wall surfaces facing each other of the first portion.

[0012] An outdoor unit according to an eight aspect is the outdoor unit according to any one of the first to seventh aspects, in which the bottom portion of the first cover has an inclined portion inclined downward toward the casing.

[0013] An outdoor unit according to a ninth aspect is the outdoor unit according to any one of the first to eighth aspects, in which the connection pipe extends along the side surface of the casing.

[0014] An outdoor unit according to a tenth aspect is the outdoor unit according to any one of the first to ninth aspects and further includes a machine chamber and a fan chamber in the casing. The fan chamber includes a fan. The openings exist between the machine chamber and the pipe connection parts. The openings are configured to allow air to be sucked into the fan chamber by the fan.

[0015] An outdoor unit according to an eleventh aspect is the outdoor unit according to any one of the first to tenth aspects, in which the total area of the openings is larger than the total area of other gaps existing between the first cover and the casing.

[0016] A method of assembling an outdoor unit according to a twelfth aspect is a method of assembling the outdoor unit according to any one of the first to eleventh aspects. The method of assembling the outdoor unit includes a step of attaching the first portion with the first cover opened, a step of connecting the refrigerant pipe, and a step of closing the first cover.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 is a schematic view showing a configuration of an air conditioner 100. FIG. 2A is a perspective view showing an external appearance of an outdoor unit 10 from which a second cover 58 is removed. FIG. 2B is a perspective view showing an external appearance of the outdoor unit 10 to which the second cover 58 is attached. FIG. 3 is a front view schematically showing the structure of the outdoor unit 10. FIG. 4 is a side view of the outdoor unit 10 from which a first cover 40 is removed. FIG. 5 is a perspective view of the vicinity of the first cover 40 of a casing 50 of the outdoor unit 10. FIG. 6 is an enlarged view of the vicinity of the first cover 40 of the outdoor unit 10. FIG. 7 is a flowchart showing a method of assembling the outdoor unit 10. DESCRIPTION OF EMBODIMENTS

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following embodiments are essentially preferred examples, and are not intended to limit the scope of the present disclosure, its application, or its use. In addition, configurations of the respective embodiments, modifications, other examples, and the like described below can be combined or partially replaced within the scope in which the present disclosure can be implemented.(1) Overall configuration

[0019] An outdoor unit 10 according to an embodiment of the present disclosure is used in an air conditioner. FIG. 1 is a schematic view of an air conditioner 100 including the outdoor unit 10. The air conditioner 100 circulates a refrigerant to provide a user with cold heat or hot heat acquired from a heat source. The air conditioner 100 provides cold heat to the user in a cold heat utilization operation. The air conditioner 100 provides hot heat to the user in a hot heat utilization operation. The air conditioner 100 can be configured as a mode such as an air conditioner, a refrigerator, a freezer, a hot water supplier, or a floor heater. When the air conditioner 100 is an air conditioner, the cold heat utilization operation and the hot heat utilization operation correspond to a cooling operation and a heating operation, respectively.

[0020] The air conditioner 100 includes the outdoor unit 10, an indoor unit 20, and a connection pipe 30. The indoor unit 20 and the outdoor unit 10 are connected by the connection pipe 30 to form a refrigerant circulation path. The refrigerant is a highly flammable refrigerant. Examples of the highly flammable refrigerant include R290 (propane), R50 (methane), R170 (ethane), R600 (butane), and R1270 (propylene).

[0021] The connection pipe 30 includes a liquid connection pipe 31 and a gas connection pipe 32. The liquid connection pipe 31 mainly allows the refrigerant in a liquid state or a gas-liquid two-phase state to pass therethrough. The liquid connection pipe 31 connects a liquid shutoff valve 17 and a utilization heat exchanger 23. The gas connection pipe 32 mainly allows the refrigerant in a high-pressure gas state or a low-pressure gas state to pass therethrough. The gas connection pipe 32 connects a gas shutoff valve 18 and the utilization heat exchanger 23.(2) Detailed configuration(2-1) Outdoor unit 10

[0022] The outdoor unit 10 acquires cold heat or hot heat from air as a heat source. The outdoor unit 10 includes a casing 50, a refrigerant pipe 90, a compressor 11, a four-way switching valve 12, a heat source heat exchanger 13, a heat source fan 14, a heat source expansion valve 15, an accumulator 16, the liquid shutoff valve 17, the gas shutoff valve 18, a refrigerant detection sensor 94, a heat source control unit 19, openings O (shown in FIGS. 4 and 5) that communicate the inside and the outside of the casing 50, pipe connection parts 80, a first cover 40, and a second cover 58 (shown in FIG. 2B). The members are connected by the refrigerant pipe 90.(2-1-1) Casing 50

[0023] The casing 50 accommodates constituent elements of the outdoor unit 10, such as the compressor 11. As shown in FIG. 2A, the casing 50 includes a top panel 51, a bottom plate 52, a first side plate 53, a second side plate 54, a front panel 55, a rear panel 56, and a front grille 57. The front grille 57 may be considered to constitute a part of the front panel 55.

[0024] The top panel 51 and the bottom plate 52 both extend in a horizontal longitudinal direction x and a horizontal transverse direction y of the casing 50. The first side plate 53 and the second side plate 54 both extend in the horizontal transverse direction y and a vertical direction z. The front panel 55 and the rear panel 56 both extend in the horizontal longitudinal direction x and the vertical direction z.

[0025] The first side plate 53 and the second side plate 54 are separated from each other in the horizontal longitudinal direction x of the casing 50. The front panel 55 and the rear panel 56 are separated in the horizontal transverse direction y of the casing 50. The second side plate 54 has the openings O. The connection pipe 30 extends along the second side plate 54. More preferably, the connection pipe 30 extends along the second side plate 54 and then extends in a back surface direction of the casing 50.

[0026] As shown in FIG. 3, the casing 50 has an internal space S. The internal space S is provided with a first partition plate 60 and a second partition plate 70. The first partition plate 60 is a plate-shaped member that has irregularities or an opening and extends generally in the horizontal direction. The first partition plate 60 partitions the internal space S into an upper space S1 and a lower space S2. The second partition plate 70 is a plate-shaped member that extends generally in the vertical direction. The second partition plate 70 partitions the lower space S2 into a fan chamber S3 and a machine chamber S4. The fan chamber S3 is located near the first side plate 53. The machine chamber S4 is located near the second side plate 54.

[0027] The casing 50 has a height of 580 to 720 mm, a depth of 270 to 330 mm, and a width of 780 to 860 mm.(2-1-2) Refrigerant pipe 90

[0028] As shown in FIG. 1, the refrigerant pipe 90 includes a liquid refrigerant pipe 91 and a gas refrigerant pipe 92. The liquid refrigerant pipe 91 mainly allows the refrigerant in the liquid state or the gas-liquid two-phase state to pass therethrough. The liquid refrigerant pipe 91 connects the liquid shutoff valve 17 and the heat source heat exchanger 13. The gas refrigerant pipe 92 mainly allows the refrigerant in the high-pressure gas state or the low-pressure gas state to pass therethrough. The gas refrigerant pipe 92 connects the gas shutoff valve 18 and the heat source heat exchanger 13.(2-1-3) Compressor 11

[0029] The compressor 11 includes a suction pipe 11a and a discharge pipe 11b. The compressor 11 sucks the refrigerant in a low-pressure gas state from the suction pipe 11a, compresses the refrigerant, and discharges the refrigerant in a high-pressure gas state from the discharge pipe 11b. As shown in FIG. 3, the compressor 11 is disposed in the machine chamber S4 of the lower space S2.(2-1-4) Four-way switching valve 12

[0030] The four-way switching valve 12 switches between the cold heat utilization operation and the hot heat utilization operation by switching a traveling direction of the refrigerant. When the cold heat utilization operation is performed, the four-way switching valve 12 forms a connection indicated by a solid line in FIG. 1 and causes the refrigerant to advance in a direction indicated by an arrow CO. When the hot heat utilization operation is performed, the four-way switching valve 12 forms a connection indicated by a broken line in FIG. 1 and causes the refrigerant to advance in a direction indicated by an arrow HO. The four-way switching valve 12 is disposed in the machine chamber S4 of the lower space S2.(2-1-5) Heat source heat exchanger 13

[0031] The heat source heat exchanger 13 causes the refrigerant to acquire cold heat or hot heat by performing heat exchange between air as a heat source and the refrigerant. When the cold heat utilization operation is performed, the heat source heat exchanger 13 functions as a condenser or a radiator for the refrigerant, and causes the refrigerant to acquire cold heat. When the hot heat utilization operation is performed, the heat source heat exchanger 13 functions as an evaporator or a heat absorber of the refrigerant, and causes the refrigerant to acquire hot heat. As shown in FIG. 3, the heat source heat exchanger 13 is disposed in the fan chamber S3 of the lower space S2.(2-1-6) Heat source fan 14

[0032] The heat source fan 14 generates an air flow passing through the heat source heat exchanger 13 to promote heat exchange between air and the refrigerant. The heat source fan 14 includes a heat source fan blade 141 and a heat source fan motor 142. The heat source fan blade 141 generates an air flow. The heat source fan motor 142 rotates the heat source fan blade 141. The heat source fan 14 is disposed in the fan chamber S3 of the lower space S2.(2-1-7) Heat source expansion valve 15

[0033] The heat source expansion valve 15 decompresses the refrigerant. The heat source expansion valve 15 includes an electric valve having an adjustable opening degree. When the opening degree of the heat source expansion valve 15 is set small, the amount of the refrigerant that can pass through the heat source expansion valve 15 decreases, and the pressure of the refrigerant after passing through the heat source expansion valve 15 decreases. The heat source expansion valve 15 is disposed in the machine chamber S4 of the lower space S2.(2-1-8) Accumulator 16

[0034] The accumulator 16 stores only a liquid component contained in the refrigerant therein to allow only a gas component to pass therethrough. The accumulator 16 is connected to the suction pipe 11a of the compressor 11, and prevents the liquid component of the refrigerant from damaging the compressor 11. The accumulator 16 is disposed in the machine chamber S4 of the lower space S2.(2-1-9) Liquid shutoff valve 17 and gas shutoff valve 18

[0035] The liquid shutoff valve 17 and the gas shutoff valve 18 open and close the refrigerant circuit.

[0036] The liquid shutoff valve 17 and the gas shutoff valve 18 are disposed outside the casing 50 and in the vicinity of the second side plate 54 of the casing 50. The liquid shutoff valve 17 and the gas shutoff valve 18 are disposed between the machine chamber S4 and the pipe connection parts 80. The liquid shutoff valve 17 and the gas shutoff valve 18 are covered with the first cover 40.

[0037] The liquid refrigerant pipe 91 and the gas refrigerant pipe 92 are connected to the liquid shutoff valve 17 and the gas shutoff valve 18, respectively. The liquid connection pipe 31 and the gas connection pipe 32 are connected to the liquid shutoff valve 17 and the gas shutoff valve 18, respectively.

[0038] The liquid shutoff valve 17 and the gas shutoff valve 18 shut off movement of the refrigerant in installation work of the air conditioner 100 and the like. The liquid shutoff valve 17 and the gas shutoff valve 18 are manually opened and closed by an installation operator of the air conditioner 100.(2-1-10) Refrigerant detection sensor 94

[0039] The refrigerant detection sensor 94 is disposed in the casing 50. Specifically, the refrigerant detection sensor 94 is disposed at a lower portion in the machine chamber S4 in the casing 50.

[0040] The refrigerant detection sensor 94 detects the refrigerant leaking from the refrigerant circuit constituting the outdoor unit 10. Since the refrigerant detection sensor 94 is disposed at the lower portion in the machine chamber S4, when a refrigerant having a specific gravity larger than that of air leaks, the refrigerant detection sensor 94 can easily detect the leaking refrigerant quickly.(2-1-11) Openings O

[0041] As shown in FIGS. 4 and 5, the openings O are formed on the side surface of the casing 50. The openings O are configured to allow air to be sucked into the fan chamber S3 by the fan. Specifically, the openings O are formed in a lower portion of the second side plate 54 of the casing 50. Therefore, when the refrigerant having a specific gravity larger than that of air leaks, the leaking refrigerant easily passes through the openings O formed in the lower portion of the casing 50 and is guided to the machine chamber S4.

[0042] The shape of the openings O is not particularly limited. The shape of the openings O may be a rounded rectangle as shown in FIG. 5, or may be any shape such as a slit shape. The openings O allow the inside and the outside of the casing 50 to communicate with each other.

[0043] A plurality of openings O exist between the machine chamber S4 and the pipe connection parts 80. The total area of the openings O is larger than the total area of other gaps existing between the first cover 40 and the casing 50.

[0044] The area of each opening O is larger than the total area of the other gaps existing between the first cover 40 and the casing 50.(2-1-12) Pipe connection parts 80

[0045] As shown in FIGS. 1 and 4, the pipe connection parts 80 connect the refrigerant pipe 90 and the connection pipe 30 extending from the indoor unit 20.

[0046] The pipe connection parts 80 and the side surface of the second side plate 54 of the casing 50 are separated from each other.

[0047] The pipe connection parts 80 and the respective openings O face each other. Specifically, the pipe connection parts 80 at least partially overlap the respective openings O in a side view when the outdoor unit 10 is viewed from the longitudinal direction.(2-1-13) First cover 40

[0048] As shown in FIG. 6, the first cover 40 is disposed at a lower portion outside the second side plate 54 of the casing 50. The first cover 40 is disposed so as to cover both the openings O of the casing 50 and the pipe connection parts 80. In a side view as viewed from the longitudinal direction of the outdoor unit 10, the first cover 40 is disposed so as to completely cover the openings O of the casing 50. However, when the bottom plate 52 of the casing 50 overlaps the lower portion of the openings O, the first cover 40 does not necessarily cover the lower portion of the openings O. In such case, the lower portion of the first cover 40 covers the upper portion of the bottom plate 52.

[0049] The first cover 40 fills the inside of the first cover 40 with the refrigerant leaking from the pipe connection parts 80, and guides the leaking refrigerant to the machine chamber S4 through the openings O of the casing 50. The openings O are formed in a lower portion of the side surface of the casing 50, and the refrigerant detection sensor 94 is also disposed at a lower portion of the machine chamber S4 in the casing 50. Therefore, the leaking refrigerant guided to the first cover 40 can be quickly detected.

[0050] The material of the first cover 40 is not limited, and is, for example, resin.

[0051] The first cover 40 includes a first portion 41, a second portion 42, and a coupling portion 43. The first portion 41 and the second portion 42 are openable and closable by relative movement via the coupling portion 43.

[0052] The first portion 41 is fixed to the side surface of the second side plate 54 of the casing 50. The method of fixing the first portion 41 is not limited, and examples thereof include providing claws on the surface of the first portion 41 near the second side plate 54. As shown in FIG. 4, small holes O1 are formed in the second side plate 54. In the present embodiment, the number of claws is four, and the number of holes O1 is four. By hooking the claws on the respective holes O1, the first portion 41 can be fixed.

[0053] As shown in FIGS. 2A and 6, the second portion 42 is openable and closable with respect to the first portion 41 by the coupling portion 43. FIG. 2A shows a state in which the second portion 42 is closed with respect to the first portion 41. FIG. 6 shows a state in which the second portion 42 is opened with respect to the first portion 41.

[0054] The coupling portion 43 is disposed between the first portion 41 and the second portion 42. The coupling portion 43 is a rotating structure. Specifically, the coupling portion 43 is a hinge.

[0055] The first cover 40 has connection holes 46, through which the connection pipe 30 passes, on its side surface. The connection holes 46 allow the inside and the outside of the first cover 40 to communicate with each other. The connection holes 46 are formed by a part of the first portion 41 and a part of the second portion 42. The first portion 41 and the second portion 42 are combined to form the connection holes 46.

[0056] The first cover 40 further includes a pressure sensor cover portion 47. The pressure sensor cover portion 47 covers a pressure sensor 95.

[0057] The first cover 40 further includes a reinforcing member 44. The reinforcing member 44 extends so as to cross the inner wall surfaces facing each other of the first portion 41. The reinforcing member 44 may couple one side surface of the first portion 41 and the pressure sensor cover portion 47 disposed in the vicinity of the opposite side surface in the transverse direction. The reinforcing member 44 may directly couple one side surface of the first portion 41 of the first cover 40 and the opposite side surface.

[0058] The bottom portion of the first cover 40 has an inclined portion 45. The inclined portion 45 is inclined downward toward the casing 50.(2-1-14) Second cover 58

[0059] As shown in FIG. 2B, the second cover 58 covers the first cover 40. The second cover 58 may cover the entire side surface of the casing 50 near the second side plate 54. The second cover 58 may cover a terminal block 88.

[0060] The second cover 58 is removable. FIG. 2B is a perspective view showing a state in which the second cover 58 is attached to the perspective view of FIG. 2A.(2-1-15) Pressure sensor 95

[0061] The pressure sensor 95 is disposed between the gas shutoff valve 18 and the pipe connection parts 80. The pressure sensor 95 measures pressure inside the connection pipe 30.(2-1-16) Terminal block 88

[0062] The terminal block 88 is disposed above the liquid shutoff valve 17 and the gas shutoff valve 18. The terminal block 88 is a portion to which wiring for inputting an alternating current from an AC power source is connected.(2-1-17) Heat source control unit 19

[0063] As shown in FIG. 1, the heat source control unit 19 is a computer that performs various calculations. The heat source control unit 19 acquires signals from various sensors including a temperature sensor or the pressure sensor 95 in addition to the refrigerant detection sensor 94. The heat source control unit 19 further controls actuators mounted on the compressor 11, the four-way switching valve 12, the heat source fan 14, the heat source expansion valve 15, and other components.(2-2) Indoor unit 20

[0064] The indoor unit 20 provides the user with cold heat or hot heat acquired by the outdoor unit 10 from the heat source. The indoor unit 20 includes a casing 21, the utilization heat exchanger 23, and a utilization fan 24.

[0065] The connection pipe 30 extends from the indoor unit 20 toward the outdoor unit 10.(2-2-1) Casing 21

[0066] The casing 21 accommodates constituent elements of the indoor unit 20 including the utilization heat exchanger 23.(2-2-2) Utilization heat exchanger 23

[0067] The utilization heat exchanger 23 provides cold heat or hot heat to the user by performing heat exchange between the refrigerant and air in an environment where the user is present or water used by the user. When the cold heat utilization operation is performed, the utilization heat exchanger 23 functions as an evaporator or a heat absorber of the refrigerant and provides cold heat to the user. When the hot heat utilization operation is performed, the utilization heat exchanger 23 functions as an evaporator or a heat absorber of the refrigerant and provides hot heat to the user.(2-2-3) Utilization fan 24

[0068] The utilization fan 24 is provided in a case where the user uses cold heat or hot heat via air. The utilization fan 24 generates an air flow passing through the utilization heat exchanger 23 to promote heat exchange between air and the refrigerant.(2-2-4) Utilization control unit 29

[0069] The utilization control unit 29 is a computer that performs various calculations. The utilization control unit 29 acquires signals from various sensors. Furthermore, the utilization control unit 29 controls a motor mounted on the utilization fan 24. In addition, the utilization control unit 29 exchanges information with the heat source control unit 19 by communicating with the heat source control unit 19.(3) Method of assembling outdoor unit 10

[0070] As shown in FIG. 7, the method of assembling the outdoor unit 10 includes a first step ST1, a second step ST2, and a third step ST3.

[0071] In the first step ST1, as shown in FIGS. 5 and 6, the first portion 41 is attached to the outside of the second side plate 54 of the casing 50 with the first cover 40 opened. The claws of the first portion 41 are hooked on the respective holes O1 of the casing 50. At this time, the first portion 41 is attached so as to entirely surround the openings O of the casing 50.

[0072] In the second step ST2, the refrigerant pipe 90 including the liquid shutoff valve 17 and the gas shutoff valve 18 is connected to the connection pipe 30. The pipe connection parts 80 between the refrigerant pipe 90 and the connection pipe 30 are accommodated in a range surrounded by the first portion 41. The connection pipe 30 is aligned with the portion of the connection holes 46 of the first portion 41.

[0073] In the third step ST3, as shown in FIG. 2A, the first cover 40 is closed. At this time, the first cover 40 encloses the connection pipe 30 to align the connection pipe 30 with the portions of the connection holes 46. Accordingly, the connection holes 46 are formed, and the connection pipe 30 allows the inside and the outside of the first cover 40 to communicate with each other.(4) Overall operation(4-1) Cold heat utilization operation

[0074] When the cold heat utilization operation is performed, the four-way switching valve 12 forms the connection indicated by the solid line in FIG. 1 and causes the refrigerant to advance in the direction indicated by the arrow CO.

[0075] The compressor 11 sucks the refrigerant in the low-pressure gas state from the suction pipe 11a, and discharges the refrigerant in the high-pressure gas state from the discharge pipe 11b. The refrigerant in the high-pressure gas state passes through the four-way switching valve 12 and reaches the heat source heat exchanger 13. The heat source heat exchanger 13 condenses the refrigerant by using cold heat of air to generate the refrigerant in a high-pressure liquid state. The refrigerant in the high-pressure liquid state is decompressed in the heat source expansion valve 15 to become the refrigerant in the gas-liquid two-phase state. Thereafter, the refrigerant passes through the liquid shutoff valve 17 and the liquid connection pipe 31, and reaches the utilization heat exchanger 23. The utilization heat exchanger 23 evaporates the refrigerant in the gas-liquid two-phase state to provide the user with cold heat carried by the refrigerant, and generates the refrigerant in the low-pressure gas state. Thereafter, the refrigerant sequentially passes through the gas connection pipe 32, the gas shutoff valve 18, the four-way switching valve 12, and the accumulator 16, and then is sucked into the compressor 11 through the suction pipe 11a.(4-2) Hot heat utilization operation

[0076] When the hot heat utilization operation is performed, the four-way switching valve 12 forms the connection indicated by the broken line in FIG. 1 and causes the refrigerant to advance in the direction indicated by the arrow HO.

[0077] The compressor 11 sucks the refrigerant in the low-pressure gas state from the suction pipe 11a, and discharges the refrigerant in the high-pressure gas state from the discharge pipe 11b. The refrigerant in the high-pressure gas state sequentially passes through the four-way switching valve 12, the gas shutoff valve 18, and the gas connection pipe 32, and reaches the utilization heat exchanger 23. The utilization heat exchanger 23 condenses the refrigerant in the high-pressure gas state to provide the user with hot heat carried by the refrigerant and generate the refrigerant in the high-pressure liquid state. Thereafter, the refrigerant passes through the liquid connection pipe 31 and the liquid shutoff valve 17, and reaches the heat source expansion valve 15. The refrigerant in the high-pressure liquid state is decompressed in the heat source expansion valve 15 to become the refrigerant in the gas-liquid two-phase state. Thereafter, the refrigerant reaches the heat source heat exchanger 13. In the heat source heat exchanger 13, the refrigerant in the low-pressure gas state is generated by hot heat of air evaporating the refrigerant. Thereafter, the refrigerant sequentially passes through the four-way switching valve 12 and the accumulator 16, and then is sucked into the compressor 11 through the suction pipe 11a.(5) Features(5-1)

[0078] The outdoor unit 10 includes the casing 50, the refrigerant pipe 90, the refrigerant detection sensor 94, the openings O that communicate the inside and the outside of the casing 50, the pipe connection parts 80, the first cover 40, and the second cover 58. The casing 50 includes the second side plate 54. The refrigerant pipe 90 is disposed in the casing 50. The refrigerant flows through the refrigerant pipe 90. The refrigerant detection sensor 94 is disposed in the casing 50. The openings O that communicate the inside and the outside of the casing 50 are formed on a side surface of the casing 50. The pipe connection parts 80 connect the refrigerant pipe 90 and the connection pipe 30 extending from the indoor unit 20. The first cover 40 includes the first portion 41, the second portion 42, and the coupling portion 43. The coupling portion 43 is disposed between the first portion 41 and the second portion 42. The first cover 40 covers the openings O and the pipe connection parts 80. The second cover 58 covers the second side plate 54 and the first cover 40. The first portion 41 and the second portion 42 are openable and closable by relative movement via the coupling portion 43.

[0079] Refrigerant leakage may occur at the pipe connection parts 80. The outdoor unit 10 of the present embodiment includes the first cover 40 that covers the periphery of the pipe connection parts 80. As a result, even if the refrigerant leaks at the pipe connection parts 80, the first cover 40 prevents the refrigerant from going outward from the outdoor unit 10 and draws the refrigerant into the outdoor unit 10. Therefore, the refrigerant having high concentration can be quickly detected by refrigerant detection sensor 94 disposed in the casing 50. As a result, refrigerant leakage can be detected with high accuracy.

[0080] Furthermore, since the first cover 40 includes the coupling portion 43, maintainability and workability are improved.(5-2)

[0081] The coupling portion 43 of the first cover 40 is a rotating structure.

[0082] In this configuration, the coupling portion 43 being a rotating structure such as a hinge facilitates opening and closing.(5-3)

[0083] The pipe connection parts 80 and the second side plate 54 of the casing 50 are separated from each other.

[0084] In this configuration, the pipe connection parts 80 and the second side plate 54 of the casing 50 are separated from each other, thereby improving workability.(5-4)

[0085] The openings O on the side surface of the casing 50 and the respective pipe connection parts 80 are positioned at least partially overlapping each other.

[0086] In this configuration, when refrigerant leakage occurs at the pipe connection parts 80, the leaking refrigerant can be quickly drawn into the casing 50.(5-5)

[0087] The outdoor unit 10 further includes the liquid shutoff valve 17 and the gas shutoff valve 18. The liquid shutoff valve 17 and the gas shutoff valve 18 open and close the refrigerant circuit. The liquid shutoff valve 17 and the gas shutoff valve 18 are covered with the first cover 40.

[0088] In this configuration, the liquid shutoff valve 17 and the gas shutoff valve 18 can be covered with the first cover 40.(5-6)

[0089] The first cover 40 has the reinforcing member 44 extending so as to cross the inner wall surfaces facing each other of the first portion 41.

[0090] In this configuration, the strength of the first cover 40 can be increased.(5-7)

[0091] The bottom portion of the first cover 40 has the inclined portion 45 inclined downward toward the casing 50.

[0092] In this configuration, the leaking refrigerant can be easily drawn into the outdoor unit 10.(5-8)

[0093] The outdoor unit 10 further includes the terminal block 88. The terminal block 88 is disposed on the side surface of the casing 50. The terminal block 88 is disposed above the liquid shutoff valve 17 and the gas shutoff valve 18.

[0094] In this configuration, since the terminal block 88 is disposed above the liquid shutoff valve 17 and the gas shutoff valve 18, even if refrigerant leakage occurs, the leaking refrigerant can be prevented from reaching the terminal block 88.(5-9)

[0095] The connection pipe 30 extends along a side surface of the casing 50.

[0096] In this configuration, a space in the width direction of the outdoor unit 10 can be reduced.(5-10)

[0097] The outdoor unit 10 further includes the machine chamber S4 and the fan chamber S3 in the casing 50. The fan chamber S3 includes the heat source fan 14. The openings O exist between the machine chamber S4 and the pipe connection parts 80. The openings O are configured to allow air to be sucked into the fan chamber by the fan.

[0098] In this configuration, when refrigerant leakage occurs, the leaking refrigerant drawn into the outdoor unit 10 is stirred and diluted by the air flow generated by the heat source fan 14. As a result, the high-concentration refrigerant is prevented from flowing out of the outdoor unit 10.(5-11)

[0099] The pressure sensor 95 is further provided. The pressure sensor 95 is disposed between the liquid shutoff valve 17 and the gas shutoff valve 18 and the pipe connection parts 80.

[0100] In the case of using a highly flammable refrigerant, if a piping connection execution error occurs during installation of the air conditioner 100, there is a risk regarding the leaking refrigerant. By providing the pressure sensor 95 between the liquid shutoff valve 17 and the gas shutoff valve 18 and the pipe connection parts 80, it is possible to monitor the internal pressure of the pipe at the time of installation. By checking the internal pressure of the pipe with the pressure sensor 95, it is possible to check insufficient vacuuming in the installation process and leakage due to a connection failure and to determine the installation state. As a result, the risk of refrigerant leakage due to defective execution can be reduced.(5-12)

[0101] The method of assembling the outdoor unit 10 includes the first step ST1 of attaching the first portion 41 with the first cover 40 opened, the second step ST2 of connecting the refrigerant pipe 90, and the third step ST3 of closing the first cover 40.

[0102] In this assembling method, the first portion 41 is attached to the casing 50 and then the first cover 40 is closed, which facilitates positioning at the time of attaching the first cover 40. In addition, the first cover 40 being openable and closable improves maintainability and workability.(6) Modifications(6-1) Modification A

[0103] In the above embodiment, the coupling portion 43 is a hinge, but this is not limiting. The coupling portion 43 may be, for example, a sliding type. In the present modification A, the second portion 42 slides with respect to the first portion 41 to open and close the first cover 40.(6-2) Modification B

[0104] In the above embodiment, the plurality of openings O are provided, but this is not limiting. The opening O may be one hole larger than that shown in FIG. 5. The shape of the opening O may be an irregular shape, or may be any shape such as a slit shape. In the case of the present modification, the area of the opening O is larger than the total area of other gaps existing between the first cover 40 and the casing 50.(6-3) Modification C

[0105] In the above embodiment, the first cover has two portions so as to have the first portion and the second portion, but may have three or more portions.

[0106] Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the gist and scope of the present disclosure disclosed in claims. In addition, the above embodiments and modifications may be appropriately combined or replaced as long as functions of an object of the present disclosure are not impaired. The above descriptions of "first", "second", ... are used to distinguish words and phrases to which these descriptions are given, and the number and order of the words and phrases are not limited.INDUSTRIAL APPLICABILITY

[0107] As described above, the present disclosure is useful for indoor units and air conditioners.REFERENCE SIGNS LIST

[0108] 10: outdoor unit 13: heat source heat exchanger (example of heat exchanger) 14: heat source fan (example of fan) 17: liquid shutoff valve (example of shutoff valve) 18: gas shutoff valve (example of shutoff valve) 19: heat source control unit 20: indoor unit 30: connection pipe 31: liquid connection pipe 32: gas connection pipe 40: first cover 41: first portion 42: second portion 43: coupling portion 44: reinforcing member 45: inclined portion 50: casing 54: second side plate (example of side surface of casing) 58: second cover 80: pipe connection part 88: terminal block 90: refrigerant pipe 91: liquid refrigerant pipe 92: gas refrigerant pipe 94: refrigerant detection sensor 95: pressure sensor 100: air conditioner O: opening S3: fan chamber S4: machine chamber

Examples

Embodiment Construction

[0018]Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following embodiments are essentially preferred examples, and are not intended to limit the scope of the present disclosure, its application, or its use. In addition, configurations of the respective embodiments, modifications, other examples, and the like described below can be combined or partially replaced within the scope in which the present disclosure can be implemented.

(1) Overall configuration

[0019]An outdoor unit 10 according to an embodiment of the present disclosure is used in an air conditioner. FIG. 1 is a schematic view of an air conditioner 100 including the outdoor unit 10. The air conditioner 100 circulates a refrigerant to provide a user with cold heat or hot heat acquired from a heat source. The air conditioner 100 provides cold heat to the user in a cold heat utilization operation. The air conditioner 100 provides hot heat to the user in a hot ...

TECHNICAL FIELD

[0001] The present invention relates to an outdoor unit and a method of assembling the outdoor unit.BACKGROUND ART

[0002] WO 2022 / 107220 A1 describes an air conditioner using a flammable or mildly flammable refrigerant.SUMMARY OF THE INVENTION <Technical Problem>

[0003] In recent years, a highly flammable refrigerant that is particularly easily combusted among flammable refrigerants may be used in air conditioners. When a high-concentration highly flammable refrigerant leaks from a refrigerant circuit of an air conditioner, it is required to detect refrigerant leakage with high accuracy.<Solution to Problem>

[0004] An outdoor unit according to a first aspect includes a casing, a refrigerant pipe, a refrigerant detection sensor, openings that communicate the inside and the outside of the casing, pipe connection parts, a first cover, and a second cover. The refrigerant pipe is disposed in the casing. A refrigerant flows through the refrigerant pipe. The refrigerant detection sensor is disposed in the casing. The openings that communicate the inside and the outside of the casing are formed on a side surface of the casing. The pipe connection parts connect the refrigerant pipe and a connection pipe extending from an indoor unit. The first cover includes a first portion, a second portion, and a coupling portion. The coupling portion is disposed between the first portion and the second portion. The first cover covers the openings and the pipe connection parts. The second cover covers the first cover. The first portion and the second portion of the first cover are openable and closable by relative movement via the coupling portion.

[0005] With this outdoor unit, refrigerant leakage can be detected with high accuracy.

[0006] An outdoor unit according to a second aspect is the outdoor unit according to the first aspect, in which the coupling portion is a rotating structure.

[0007] An outdoor unit according to a third aspect is the outdoor unit according to the first or second aspect, in which the pipe connection parts and the side surface of the casing are separated from each other.

[0008] An outdoor unit according to a fourth aspect is the outdoor unit according to any one of the first to third aspects, and further includes a shutoff valve. The shutoff valve opens and closes the refrigerant circuit. The shutoff valve is covered with the first cover.

[0009] An outdoor unit according to a fifth aspect is the outdoor unit according to the fourth aspect and further includes a terminal block. The terminal block is disposed on the side surface of the casing. The terminal block is disposed above the shutoff valve.

[0010] An outdoor unit according to an sixth aspect is the outdoor unit according to the fourth or fifth aspect and further includes a pressure sensor. The pressure sensor is disposed between the shutoff valve and the pipe connection parts.

[0011] An outdoor unit according to a seventh aspect is the outdoor unit according to any one of the first to sixth aspects, in which the first cover includes a reinforcing member extending so as to cross the inner wall surfaces facing each other of the first portion.

[0012] An outdoor unit according to an eight aspect is the outdoor unit according to any one of the first to seventh aspects, in which the bottom portion of the first cover has an inclined portion inclined downward toward the casing.

[0013] An outdoor unit according to a ninth aspect is the outdoor unit according to any one of the first to eighth aspects, in which the connection pipe extends along the side surface of the casing.

[0014] An outdoor unit according to a tenth aspect is the outdoor unit according to any one of the first to ninth aspects and further includes a machine chamber and a fan chamber in the casing. The fan chamber includes a fan. The openings exist between the machine chamber and the pipe connection parts. The openings are configured to allow air to be sucked into the fan chamber by the fan.

[0015] An outdoor unit according to an eleventh aspect is the outdoor unit according to any one of the first to tenth aspects, in which the total area of the openings is larger than the total area of other gaps existing between the first cover and the casing.

[0016] A method of assembling an outdoor unit according to a twelfth aspect is a method of assembling the outdoor unit according to any one of the first to eleventh aspects. The method of assembling the outdoor unit includes a step of attaching the first portion with the first cover opened, a step of connecting the refrigerant pipe, and a step of closing the first cover.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 is a schematic view showing a configuration of an air conditioner 100. FIG. 2A is a perspective view showing an external appearance of an outdoor unit 10 from which a second cover 58 is removed. FIG. 2B is a perspective view showing an external appearance of the outdoor unit 10 to which the second cover 58 is attached. FIG. 3 is a front view schematically showing the structure of the outdoor unit 10. FIG. 4 is a side view of the outdoor unit 10 from which a first cover 40 is removed. FIG. 5 is a perspective view of the vicinity of the first cover 40 of a casing 50 of the outdoor unit 10. FIG. 6 is an enlarged view of the vicinity of the first cover 40 of the outdoor unit 10. FIG. 7 is a flowchart showing a method of assembling the outdoor unit 10. DESCRIPTION OF EMBODIMENTS

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following embodiments are essentially preferred examples, and are not intended to limit the scope of the present disclosure, its application, or its use. In addition, configurations of the respective embodiments, modifications, other examples, and the like described below can be combined or partially replaced within the scope in which the present disclosure can be implemented.(1) Overall configuration

[0019] An outdoor unit 10 according to an embodiment of the present disclosure is used in an air conditioner. FIG. 1 is a schematic view of an air conditioner 100 including the outdoor unit 10. The air conditioner 100 circulates a refrigerant to provide a user with cold heat or hot heat acquired from a heat source. The air conditioner 100 provides cold heat to the user in a cold heat utilization operation. The air conditioner 100 provides hot heat to the user in a hot heat utilization operation. The air conditioner 100 can be configured as a mode such as an air conditioner, a refrigerator, a freezer, a hot water supplier, or a floor heater. When the air conditioner 100 is an air conditioner, the cold heat utilization operation and the hot heat utilization operation correspond to a cooling operation and a heating operation, respectively.

[0020] The air conditioner 100 includes the outdoor unit 10, an indoor unit 20, and a connection pipe 30. The indoor unit 20 and the outdoor unit 10 are connected by the connection pipe 30 to form a refrigerant circulation path. The refrigerant is a highly flammable refrigerant. Examples of the highly flammable refrigerant include R290 (propane), R50 (methane), R170 (ethane), R600 (butane), and R1270 (propylene).

[0021] The connection pipe 30 includes a liquid connection pipe 31 and a gas connection pipe 32. The liquid connection pipe 31 mainly allows the refrigerant in a liquid state or a gas-liquid two-phase state to pass therethrough. The liquid connection pipe 31 connects a liquid shutoff valve 17 and a utilization heat exchanger 23. The gas connection pipe 32 mainly allows the refrigerant in a high-pressure gas state or a low-pressure gas state to pass therethrough. The gas connection pipe 32 connects a gas shutoff valve 18 and the utilization heat exchanger 23.(2) Detailed configuration(2-1) Outdoor unit 10

[0022] The outdoor unit 10 acquires cold heat or hot heat from air as a heat source. The outdoor unit 10 includes a casing 50, a refrigerant pipe 90, a compressor 11, a four-way switching valve 12, a heat source heat exchanger 13, a heat source fan 14, a heat source expansion valve 15, an accumulator 16, the liquid shutoff valve 17, the gas shutoff valve 18, a refrigerant detection sensor 94, a heat source control unit 19, openings O (shown in FIGS. 4 and 5) that communicate the inside and the outside of the casing 50, pipe connection parts 80, a first cover 40, and a second cover 58 (shown in FIG. 2B). The members are connected by the refrigerant pipe 90.(2-1-1) Casing 50

[0023] The casing 50 accommodates constituent elements of the outdoor unit 10, such as the compressor 11. As shown in FIG. 2A, the casing 50 includes a top panel 51, a bottom plate 52, a first side plate 53, a second side plate 54, a front panel 55, a rear panel 56, and a front grille 57. The front grille 57 may be considered to constitute a part of the front panel 55.

[0024] The top panel 51 and the bottom plate 52 both extend in a horizontal longitudinal direction x and a horizontal transverse direction y of the casing 50. The first side plate 53 and the second side plate 54 both extend in the horizontal transverse direction y and a vertical direction z. The front panel 55 and the rear panel 56 both extend in the horizontal longitudinal direction x and the vertical direction z.

[0025] The first side plate 53 and the second side plate 54 are separated from each other in the horizontal longitudinal direction x of the casing 50. The front panel 55 and the rear panel 56 are separated in the horizontal transverse direction y of the casing 50. The second side plate 54 has the openings O. The connection pipe 30 extends along the second side plate 54. More preferably, the connection pipe 30 extends along the second side plate 54 and then extends in a back surface direction of the casing 50.

[0026] As shown in FIG. 3, the casing 50 has an internal space S. The internal space S is provided with a first partition plate 60 and a second partition plate 70. The first partition plate 60 is a plate-shaped member that has irregularities or an opening and extends generally in the horizontal direction. The first partition plate 60 partitions the internal space S into an upper space S1 and a lower space S2. The second partition plate 70 is a plate-shaped member that extends generally in the vertical direction. The second partition plate 70 partitions the lower space S2 into a fan chamber S3 and a machine chamber S4. The fan chamber S3 is located near the first side plate 53. The machine chamber S4 is located near the second side plate 54.

[0027] The casing 50 has a height of 580 to 720 mm, a depth of 270 to 330 mm, and a width of 780 to 860 mm.(2-1-2) Refrigerant pipe 90

[0028] As shown in FIG. 1, the refrigerant pipe 90 includes a liquid refrigerant pipe 91 and a gas refrigerant pipe 92. The liquid refrigerant pipe 91 mainly allows the refrigerant in the liquid state or the gas-liquid two-phase state to pass therethrough. The liquid refrigerant pipe 91 connects the liquid shutoff valve 17 and the heat source heat exchanger 13. The gas refrigerant pipe 92 mainly allows the refrigerant in the high-pressure gas state or the low-pressure gas state to pass therethrough. The gas refrigerant pipe 92 connects the gas shutoff valve 18 and the heat source heat exchanger 13.(2-1-3) Compressor 11

[0029] The compressor 11 includes a suction pipe 11a and a discharge pipe 11b. The compressor 11 sucks the refrigerant in a low-pressure gas state from the suction pipe 11a, compresses the refrigerant, and discharges the refrigerant in a high-pressure gas state from the discharge pipe 11b. As shown in FIG. 3, the compressor 11 is disposed in the machine chamber S4 of the lower space S2.(2-1-4) Four-way switching valve 12

[0030] The four-way switching valve 12 switches between the cold heat utilization operation and the hot heat utilization operation by switching a traveling direction of the refrigerant. When the cold heat utilization operation is performed, the four-way switching valve 12 forms a connection indicated by a solid line in FIG. 1 and causes the refrigerant to advance in a direction indicated by an arrow CO. When the hot heat utilization operation is performed, the four-way switching valve 12 forms a connection indicated by a broken line in FIG. 1 and causes the refrigerant to advance in a direction indicated by an arrow HO. The four-way switching valve 12 is disposed in the machine chamber S4 of the lower space S2.(2-1-5) Heat source heat exchanger 13

[0031] The heat source heat exchanger 13 causes the refrigerant to acquire cold heat or hot heat by performing heat exchange between air as a heat source and the refrigerant. When the cold heat utilization operation is performed, the heat source heat exchanger 13 functions as a condenser or a radiator for the refrigerant, and causes the refrigerant to acquire cold heat. When the hot heat utilization operation is performed, the heat source heat exchanger 13 functions as an evaporator or a heat absorber of the refrigerant, and causes the refrigerant to acquire hot heat. As shown in FIG. 3, the heat source heat exchanger 13 is disposed in the fan chamber S3 of the lower space S2.(2-1-6) Heat source fan 14

[0032] The heat source fan 14 generates an air flow passing through the heat source heat exchanger 13 to promote heat exchange between air and the refrigerant. The heat source fan 14 includes a heat source fan blade 141 and a heat source fan motor 142. The heat source fan blade 141 generates an air flow. The heat source fan motor 142 rotates the heat source fan blade 141. The heat source fan 14 is disposed in the fan chamber S3 of the lower space S2.(2-1-7) Heat source expansion valve 15

[0033] The heat source expansion valve 15 decompresses the refrigerant. The heat source expansion valve 15 includes an electric valve having an adjustable opening degree. When the opening degree of the heat source expansion valve 15 is set small, the amount of the refrigerant that can pass through the heat source expansion valve 15 decreases, and the pressure of the refrigerant after passing through the heat source expansion valve 15 decreases. The heat source expansion valve 15 is disposed in the machine chamber S4 of the lower space S2.(2-1-8) Accumulator 16

[0034] The accumulator 16 stores only a liquid component contained in the refrigerant therein to allow only a gas component to pass therethrough. The accumulator 16 is connected to the suction pipe 11a of the compressor 11, and prevents the liquid component of the refrigerant from damaging the compressor 11. The accumulator 16 is disposed in the machine chamber S4 of the lower space S2.(2-1-9) Liquid shutoff valve 17 and gas shutoff valve 18

[0035] The liquid shutoff valve 17 and the gas shutoff valve 18 open and close the refrigerant circuit.

[0036] The liquid shutoff valve 17 and the gas shutoff valve 18 are disposed outside the casing 50 and in the vicinity of the second side plate 54 of the casing 50. The liquid shutoff valve 17 and the gas shutoff valve 18 are disposed between the machine chamber S4 and the pipe connection parts 80. The liquid shutoff valve 17 and the gas shutoff valve 18 are covered with the first cover 40.

[0037] The liquid refrigerant pipe 91 and the gas refrigerant pipe 92 are connected to the liquid shutoff valve 17 and the gas shutoff valve 18, respectively. The liquid connection pipe 31 and the gas connection pipe 32 are connected to the liquid shutoff valve 17 and the gas shutoff valve 18, respectively.

[0038] The liquid shutoff valve 17 and the gas shutoff valve 18 shut off movement of the refrigerant in installation work of the air conditioner 100 and the like. The liquid shutoff valve 17 and the gas shutoff valve 18 are manually opened and closed by an installation operator of the air conditioner 100.(2-1-10) Refrigerant detection sensor 94

[0039] The refrigerant detection sensor 94 is disposed in the casing 50. Specifically, the refrigerant detection sensor 94 is disposed at a lower portion in the machine chamber S4 in the casing 50.

[0040] The refrigerant detection sensor 94 detects the refrigerant leaking from the refrigerant circuit constituting the outdoor unit 10. Since the refrigerant detection sensor 94 is disposed at the lower portion in the machine chamber S4, when a refrigerant having a specific gravity larger than that of air leaks, the refrigerant detection sensor 94 can easily detect the leaking refrigerant quickly.(2-1-11) Openings O

[0041] As shown in FIGS. 4 and 5, the openings O are formed on the side surface of the casing 50. The openings O are configured to allow air to be sucked into the fan chamber S3 by the fan. Specifically, the openings O are formed in a lower portion of the second side plate 54 of the casing 50. Therefore, when the refrigerant having a specific gravity larger than that of air leaks, the leaking refrigerant easily passes through the openings O formed in the lower portion of the casing 50 and is guided to the machine chamber S4.

[0042] The shape of the openings O is not particularly limited. The shape of the openings O may be a rounded rectangle as shown in FIG. 5, or may be any shape such as a slit shape. The openings O allow the inside and the outside of the casing 50 to communicate with each other.

[0043] A plurality of openings O exist between the machine chamber S4 and the pipe connection parts 80. The total area of the openings O is larger than the total area of other gaps existing between the first cover 40 and the casing 50.

[0044] The area of each opening O is larger than the total area of the other gaps existing between the first cover 40 and the casing 50.(2-1-12) Pipe connection parts 80

[0045] As shown in FIGS. 1 and 4, the pipe connection parts 80 connect the refrigerant pipe 90 and the connection pipe 30 extending from the indoor unit 20.

[0046] The pipe connection parts 80 and the side surface of the second side plate 54 of the casing 50 are separated from each other.

[0047] The pipe connection parts 80 and the respective openings O face each other. Specifically, the pipe connection parts 80 at least partially overlap the respective openings O in a side view when the outdoor unit 10 is viewed from the longitudinal direction.(2-1-13) First cover 40

[0048] As shown in FIG. 6, the first cover 40 is disposed at a lower portion outside the second side plate 54 of the casing 50. The first cover 40 is disposed so as to cover both the openings O of the casing 50 and the pipe connection parts 80. In a side view as viewed from the longitudinal direction of the outdoor unit 10, the first cover 40 is disposed so as to completely cover the openings O of the casing 50. However, when the bottom plate 52 of the casing 50 overlaps the lower portion of the openings O, the first cover 40 does not necessarily cover the lower portion of the openings O. In such case, the lower portion of the first cover 40 covers the upper portion of the bottom plate 52.

[0049] The first cover 40 fills the inside of the first cover 40 with the refrigerant leaking from the pipe connection parts 80, and guides the leaking refrigerant to the machine chamber S4 through the openings O of the casing 50. The openings O are formed in a lower portion of the side surface of the casing 50, and the refrigerant detection sensor 94 is also disposed at a lower portion of the machine chamber S4 in the casing 50. Therefore, the leaking refrigerant guided to the first cover 40 can be quickly detected.

[0050] The material of the first cover 40 is not limited, and is, for example, resin.

[0051] The first cover 40 includes a first portion 41, a second portion 42, and a coupling portion 43. The first portion 41 and the second portion 42 are openable and closable by relative movement via the coupling portion 43.

[0052] The first portion 41 is fixed to the side surface of the second side plate 54 of the casing 50. The method of fixing the first portion 41 is not limited, and examples thereof include providing claws on the surface of the first portion 41 near the second side plate 54. As shown in FIG. 4, small holes O1 are formed in the second side plate 54. In the present embodiment, the number of claws is four, and the number of holes O1 is four. By hooking the claws on the respective holes O1, the first portion 41 can be fixed.

[0053] As shown in FIGS. 2A and 6, the second portion 42 is openable and closable with respect to the first portion 41 by the coupling portion 43. FIG. 2A shows a state in which the second portion 42 is closed with respect to the first portion 41. FIG. 6 shows a state in which the second portion 42 is opened with respect to the first portion 41.

[0054] The coupling portion 43 is disposed between the first portion 41 and the second portion 42. The coupling portion 43 is a rotating structure. Specifically, the coupling portion 43 is a hinge.

[0055] The first cover 40 has connection holes 46, through which the connection pipe 30 passes, on its side surface. The connection holes 46 allow the inside and the outside of the first cover 40 to communicate with each other. The connection holes 46 are formed by a part of the first portion 41 and a part of the second portion 42. The first portion 41 and the second portion 42 are combined to form the connection holes 46.

[0056] The first cover 40 further includes a pressure sensor cover portion 47. The pressure sensor cover portion 47 covers a pressure sensor 95.

[0057] The first cover 40 further includes a reinforcing member 44. The reinforcing member 44 extends so as to cross the inner wall surfaces facing each other of the first portion 41. The reinforcing member 44 may couple one side surface of the first portion 41 and the pressure sensor cover portion 47 disposed in the vicinity of the opposite side surface in the transverse direction. The reinforcing member 44 may directly couple one side surface of the first portion 41 of the first cover 40 and the opposite side surface.

[0058] The bottom portion of the first cover 40 has an inclined portion 45. The inclined portion 45 is inclined downward toward the casing 50.(2-1-14) Second cover 58

[0059] As shown in FIG. 2B, the second cover 58 covers the first cover 40. The second cover 58 may cover the entire side surface of the casing 50 near the second side plate 54. The second cover 58 may cover a terminal block 88.

[0060] The second cover 58 is removable. FIG. 2B is a perspective view showing a state in which the second cover 58 is attached to the perspective view of FIG. 2A.(2-1-15) Pressure sensor 95

[0061] The pressure sensor 95 is disposed between the gas shutoff valve 18 and the pipe connection parts 80. The pressure sensor 95 measures pressure inside the connection pipe 30.(2-1-16) Terminal block 88

[0062] The terminal block 88 is disposed above the liquid shutoff valve 17 and the gas shutoff valve 18. The terminal block 88 is a portion to which wiring for inputting an alternating current from an AC power source is connected.(2-1-17) Heat source control unit 19

[0063] As shown in FIG. 1, the heat source control unit 19 is a computer that performs various calculations. The heat source control unit 19 acquires signals from various sensors including a temperature sensor or the pressure sensor 95 in addition to the refrigerant detection sensor 94. The heat source control unit 19 further controls actuators mounted on the compressor 11, the four-way switching valve 12, the heat source fan 14, the heat source expansion valve 15, and other components.(2-2) Indoor unit 20

[0064] The indoor unit 20 provides the user with cold heat or hot heat acquired by the outdoor unit 10 from the heat source. The indoor unit 20 includes a casing 21, the utilization heat exchanger 23, and a utilization fan 24.

[0065] The connection pipe 30 extends from the indoor unit 20 toward the outdoor unit 10.(2-2-1) Casing 21

[0066] The casing 21 accommodates constituent elements of the indoor unit 20 including the utilization heat exchanger 23.(2-2-2) Utilization heat exchanger 23

[0067] The utilization heat exchanger 23 provides cold heat or hot heat to the user by performing heat exchange between the refrigerant and air in an environment where the user is present or water used by the user. When the cold heat utilization operation is performed, the utilization heat exchanger 23 functions as an evaporator or a heat absorber of the refrigerant and provides cold heat to the user. When the hot heat utilization operation is performed, the utilization heat exchanger 23 functions as an evaporator or a heat absorber of the refrigerant and provides hot heat to the user.(2-2-3) Utilization fan 24

[0068] The utilization fan 24 is provided in a case where the user uses cold heat or hot heat via air. The utilization fan 24 generates an air flow passing through the utilization heat exchanger 23 to promote heat exchange between air and the refrigerant.(2-2-4) Utilization control unit 29

[0069] The utilization control unit 29 is a computer that performs various calculations. The utilization control unit 29 acquires signals from various sensors. Furthermore, the utilization control unit 29 controls a motor mounted on the utilization fan 24. In addition, the utilization control unit 29 exchanges information with the heat source control unit 19 by communicating with the heat source control unit 19.(3) Method of assembling outdoor unit 10

[0070] As shown in FIG. 7, the method of assembling the outdoor unit 10 includes a first step ST1, a second step ST2, and a third step ST3.

[0071] In the first step ST1, as shown in FIGS. 5 and 6, the first portion 41 is attached to the outside of the second side plate 54 of the casing 50 with the first cover 40 opened. The claws of the first portion 41 are hooked on the respective holes O1 of the casing 50. At this time, the first portion 41 is attached so as to entirely surround the openings O of the casing 50.

[0072] In the second step ST2, the refrigerant pipe 90 including the liquid shutoff valve 17 and the gas shutoff valve 18 is connected to the connection pipe 30. The pipe connection parts 80 between the refrigerant pipe 90 and the connection pipe 30 are accommodated in a range surrounded by the first portion 41. The connection pipe 30 is aligned with the portion of the connection holes 46 of the first portion 41.

[0073] In the third step ST3, as shown in FIG. 2A, the first cover 40 is closed. At this time, the first cover 40 encloses the connection pipe 30 to align the connection pipe 30 with the portions of the connection holes 46. Accordingly, the connection holes 46 are formed, and the connection pipe 30 allows the inside and the outside of the first cover 40 to communicate with each other.(4) Overall operation(4-1) Cold heat utilization operation

[0074] When the cold heat utilization operation is performed, the four-way switching valve 12 forms the connection indicated by the solid line in FIG. 1 and causes the refrigerant to advance in the direction indicated by the arrow CO.

[0075] The compressor 11 sucks the refrigerant in the low-pressure gas state from the suction pipe 11a, and discharges the refrigerant in the high-pressure gas state from the discharge pipe 11b. The refrigerant in the high-pressure gas state passes through the four-way switching valve 12 and reaches the heat source heat exchanger 13. The heat source heat exchanger 13 condenses the refrigerant by using cold heat of air to generate the refrigerant in a high-pressure liquid state. The refrigerant in the high-pressure liquid state is decompressed in the heat source expansion valve 15 to become the refrigerant in the gas-liquid two-phase state. Thereafter, the refrigerant passes through the liquid shutoff valve 17 and the liquid connection pipe 31, and reaches the utilization heat exchanger 23. The utilization heat exchanger 23 evaporates the refrigerant in the gas-liquid two-phase state to provide the user with cold heat carried by the refrigerant, and generates the refrigerant in the low-pressure gas state. Thereafter, the refrigerant sequentially passes through the gas connection pipe 32, the gas shutoff valve 18, the four-way switching valve 12, and the accumulator 16, and then is sucked into the compressor 11 through the suction pipe 11a.(4-2) Hot heat utilization operation

[0076] When the hot heat utilization operation is performed, the four-way switching valve 12 forms the connection indicated by the broken line in FIG. 1 and causes the refrigerant to advance in the direction indicated by the arrow HO.

[0077] The compressor 11 sucks the refrigerant in the low-pressure gas state from the suction pipe 11a, and discharges the refrigerant in the high-pressure gas state from the discharge pipe 11b. The refrigerant in the high-pressure gas state sequentially passes through the four-way switching valve 12, the gas shutoff valve 18, and the gas connection pipe 32, and reaches the utilization heat exchanger 23. The utilization heat exchanger 23 condenses the refrigerant in the high-pressure gas state to provide the user with hot heat carried by the refrigerant and generate the refrigerant in the high-pressure liquid state. Thereafter, the refrigerant passes through the liquid connection pipe 31 and the liquid shutoff valve 17, and reaches the heat source expansion valve 15. The refrigerant in the high-pressure liquid state is decompressed in the heat source expansion valve 15 to become the refrigerant in the gas-liquid two-phase state. Thereafter, the refrigerant reaches the heat source heat exchanger 13. In the heat source heat exchanger 13, the refrigerant in the low-pressure gas state is generated by hot heat of air evaporating the refrigerant. Thereafter, the refrigerant sequentially passes through the four-way switching valve 12 and the accumulator 16, and then is sucked into the compressor 11 through the suction pipe 11a.(5) Features(5-1)

[0078] The outdoor unit 10 includes the casing 50, the refrigerant pipe 90, the refrigerant detection sensor 94, the openings O that communicate the inside and the outside of the casing 50, the pipe connection parts 80, the first cover 40, and the second cover 58. The casing 50 includes the second side plate 54. The refrigerant pipe 90 is disposed in the casing 50. The refrigerant flows through the refrigerant pipe 90. The refrigerant detection sensor 94 is disposed in the casing 50. The openings O that communicate the inside and the outside of the casing 50 are formed on a side surface of the casing 50. The pipe connection parts 80 connect the refrigerant pipe 90 and the connection pipe 30 extending from the indoor unit 20. The first cover 40 includes the first portion 41, the second portion 42, and the coupling portion 43. The coupling portion 43 is disposed between the first portion 41 and the second portion 42. The first cover 40 covers the openings O and the pipe connection parts 80. The second cover 58 covers the second side plate 54 and the first cover 40. The first portion 41 and the second portion 42 are openable and closable by relative movement via the coupling portion 43.

[0079] Refrigerant leakage may occur at the pipe connection parts 80. The outdoor unit 10 of the present embodiment includes the first cover 40 that covers the periphery of the pipe connection parts 80. As a result, even if the refrigerant leaks at the pipe connection parts 80, the first cover 40 prevents the refrigerant from going outward from the outdoor unit 10 and draws the refrigerant into the outdoor unit 10. Therefore, the refrigerant having high concentration can be quickly detected by refrigerant detection sensor 94 disposed in the casing 50. As a result, refrigerant leakage can be detected with high accuracy.

[0080] Furthermore, since the first cover 40 includes the coupling portion 43, maintainability and workability are improved.(5-2)

[0081] The coupling portion 43 of the first cover 40 is a rotating structure.

[0082] In this configuration, the coupling portion 43 being a rotating structure such as a hinge facilitates opening and closing.(5-3)

[0083] The pipe connection parts 80 and the second side plate 54 of the casing 50 are separated from each other.

[0084] In this configuration, the pipe connection parts 80 and the second side plate 54 of the casing 50 are separated from each other, thereby improving workability.(5-4)

[0085] The openings O on the side surface of the casing 50 and the respective pipe connection parts 80 are positioned at least partially overlapping each other.

[0086] In this configuration, when refrigerant leakage occurs at the pipe connection parts 80, the leaking refrigerant can be quickly drawn into the casing 50.(5-5)

[0087] The outdoor unit 10 further includes the liquid shutoff valve 17 and the gas shutoff valve 18. The liquid shutoff valve 17 and the gas shutoff valve 18 open and close the refrigerant circuit. The liquid shutoff valve 17 and the gas shutoff valve 18 are covered with the first cover 40.

[0088] In this configuration, the liquid shutoff valve 17 and the gas shutoff valve 18 can be covered with the first cover 40.(5-6)

[0089] The first cover 40 has the reinforcing member 44 extending so as to cross the inner wall surfaces facing each other of the first portion 41.

[0090] In this configuration, the strength of the first cover 40 can be increased.(5-7)

[0091] The bottom portion of the first cover 40 has the inclined portion 45 inclined downward toward the casing 50.

[0092] In this configuration, the leaking refrigerant can be easily drawn into the outdoor unit 10.(5-8)

[0093] The outdoor unit 10 further includes the terminal block 88. The terminal block 88 is disposed on the side surface of the casing 50. The terminal block 88 is disposed above the liquid shutoff valve 17 and the gas shutoff valve 18.

[0094] In this configuration, since the terminal block 88 is disposed above the liquid shutoff valve 17 and the gas shutoff valve 18, even if refrigerant leakage occurs, the leaking refrigerant can be prevented from reaching the terminal block 88.(5-9)

[0095] The connection pipe 30 extends along a side surface of the casing 50.

[0096] In this configuration, a space in the width direction of the outdoor unit 10 can be reduced.(5-10)

[0097] The outdoor unit 10 further includes the machine chamber S4 and the fan chamber S3 in the casing 50. The fan chamber S3 includes the heat source fan 14. The openings O exist between the machine chamber S4 and the pipe connection parts 80. The openings O are configured to allow air to be sucked into the fan chamber by the fan.

[0098] In this configuration, when refrigerant leakage occurs, the leaking refrigerant drawn into the outdoor unit 10 is stirred and diluted by the air flow generated by the heat source fan 14. As a result, the high-concentration refrigerant is prevented from flowing out of the outdoor unit 10.(5-11)

[0099] The pressure sensor 95 is further provided. The pressure sensor 95 is disposed between the liquid shutoff valve 17 and the gas shutoff valve 18 and the pipe connection parts 80.

[0100] In the case of using a highly flammable refrigerant, if a piping connection execution error occurs during installation of the air conditioner 100, there is a risk regarding the leaking refrigerant. By providing the pressure sensor 95 between the liquid shutoff valve 17 and the gas shutoff valve 18 and the pipe connection parts 80, it is possible to monitor the internal pressure of the pipe at the time of installation. By checking the internal pressure of the pipe with the pressure sensor 95, it is possible to check insufficient vacuuming in the installation process and leakage due to a connection failure and to determine the installation state. As a result, the risk of refrigerant leakage due to defective execution can be reduced.(5-12)

[0101] The method of assembling the outdoor unit 10 includes the first step ST1 of attaching the first portion 41 with the first cover 40 opened, the second step ST2 of connecting the refrigerant pipe 90, and the third step ST3 of closing the first cover 40.

[0102] In this assembling method, the first portion 41 is attached to the casing 50 and then the first cover 40 is closed, which facilitates positioning at the time of attaching the first cover 40. In addition, the first cover 40 being openable and closable improves maintainability and workability.(6) Modifications(6-1) Modification A

[0103] In the above embodiment, the coupling portion 43 is a hinge, but this is not limiting. The coupling portion 43 may be, for example, a sliding type. In the present modification A, the second portion 42 slides with respect to the first portion 41 to open and close the first cover 40.(6-2) Modification B

[0104] In the above embodiment, the plurality of openings O are provided, but this is not limiting. The opening O may be one hole larger than that shown in FIG. 5. The shape of the opening O may be an irregular shape, or may be any shape such as a slit shape. In the case of the present modification, the area of the opening O is larger than the total area of other gaps existing between the first cover 40 and the casing 50.(6-3) Modification C

[0105] In the above embodiment, the first cover has two portions so as to have the first portion and the second portion, but may have three or more portions.

[0106] Although the embodiments of the present disclosure have been described above, it will be understood that various changes in form and details can be made without departing from the gist and scope of the present disclosure disclosed in claims. In addition, the above embodiments and modifications may be appropriately combined or replaced as long as functions of an object of the present disclosure are not impaired. The above descriptions of "first", "second", ... are used to distinguish words and phrases to which these descriptions are given, and the number and order of the words and phrases are not limited.INDUSTRIAL APPLICABILITY

[0107] As described above, the present disclosure is useful for indoor units and air conditioners.REFERENCE SIGNS LIST

[0108] 10: outdoor unit 13: heat source heat exchanger (example of heat exchanger) 14: heat source fan (example of fan) 17: liquid shutoff valve (example of shutoff valve) 18: gas shutoff valve (example of shutoff valve) 19: heat source control unit 20: indoor unit 30: connection pipe 31: liquid connection pipe 32: gas connection pipe 40: first cover 41: first portion 42: second portion 43: coupling portion 44: reinforcing member 45: inclined portion 50: casing 54: second side plate (example of side surface of casing) 58: second cover 80: pipe connection part 88: terminal block 90: refrigerant pipe 91: liquid refrigerant pipe 92: gas refrigerant pipe 94: refrigerant detection sensor 95: pressure sensor 100: air conditioner O: opening S3: fan chamber S4: machine chamber

Examples

Embodiment Construction

[0018]Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following embodiments are essentially preferred examples, and are not intended to limit the scope of the present disclosure, its application, or its use. In addition, configurations of the respective embodiments, modifications, other examples, and the like described below can be combined or partially replaced within the scope in which the present disclosure can be implemented.

(1) Overall configuration

[0019]An outdoor unit 10 according to an embodiment of the present disclosure is used in an air conditioner. FIG. 1 is a schematic view of an air conditioner 100 including the outdoor unit 10. The air conditioner 100 circulates a refrigerant to provide a user with cold heat or hot heat acquired from a heat source. The air conditioner 100 provides cold heat to the user in a cold heat utilization operation. The air conditioner 100 provides hot heat to the user in a hot ...

Claims

1. An outdoor unit (10) of an air conditioner, the outdoor unit comprising: a casing (50); a refrigerant pipe (90) that is disposed in the casing and through which a refrigerant flows; a refrigerant detection sensor (94) disposed in the casing; openings (O) that are formed in a side surface (54) of the casing and communicate an inside and an outside of the casing; pipe connection parts (80) that connect the refrigerant pipe and a connection pipe (30) extending from an indoor unit; a first cover (40) that includes a first portion (41), a second portion (42), and a coupling portion (43) disposed between the first portion and the second portion, the first cover covering the openings and the pipe connection parts; and a second cover (58) that covers the first cover, wherein the first portion and the second portion of the first cover are openable and closable by relative movement via the coupling portion.

2. The outdoor unit of an air conditioner according to claim 1, wherein the coupling portion is a rotating structure.

3. The outdoor unit of an air conditioner according to claim 1 or 2, wherein the pipe connection parts and the side surface of the casing are separated from each other.

4. The outdoor unit of an air conditioner according to any one of claims 1 to 3, further comprising a shutoff valve (17,18) that is provided in a vicinity of the side surface of the casing and opens and closes a refrigerant circuit, wherein the shutoff valve is covered with the first cover.

5. The outdoor unit of an air conditioner according to claim 4, further comprising a terminal block (88) on the side surface of the casing, wherein the terminal block is disposed above the shutoff valve.

6. The outdoor unit of an air conditioner according to claim 4 or 5, further comprising a pressure sensor (95) between the shutoff valve and the pipe connection parts.

7. The outdoor unit of an air conditioner according to any one of claims 1 to 6, wherein the first cover includes a reinforcing member (44) extending so as to cross inner wall surfaces facing each other of the first portion.

8. The outdoor unit of an air conditioner according to any one of claims 1 to 7, wherein a bottom portion of the first cover has an inclined portion (45) inclined downward toward the casing.

9. The outdoor unit of an air conditioner according to any one of claims 1 to 8, wherein the connection pipe extends along the side surface of the casing.

10. The outdoor unit of an air conditioner according to any one of claims 1 to 9, further comprising: in the casing, a machine chamber (S4); and a fan chamber (S3) having a fan (14), wherein the openings exist between the machine chamber and the pipe connection parts, and are configured to allow air to be sucked into the fan chamber by the fan.

11. The outdoor unit of an air conditioner according to any one of claims 1 to 10, wherein a total area of the openings is larger than a total area of other gaps existing between the first cover and the casing.

12. A method of assembling the outdoor unit of an air conditioner according to any one of claims 1 to 11, the method comprising: a step (ST1) of attaching the first portion with the first cover opened; a step (ST2) of connecting the refrigerant pipe; and a step (ST3) of closing the first cover.

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