EP4607100A1

EP4607100A1 - Air conditioner

Info

Publication number: EP4607100A1
Application number: EP25158813.3A
Authority: EP
Inventors: Masayuki Nonaka; Ryoichi Takafuji; Koji Naito
Original assignee: Panasonic Corp; Fujitsu General Ltd; Hitachi Johnson Controls Air Conditioning Inc
Current assignee: Panasonic Corp; Fujitsu General Ltd; Hitachi Johnson Controls Air Conditioning Inc
Priority date: 2024-02-20
Filing date: 2025-02-19
Publication date: 2025-08-27
Also published as: CN120521249A; AU2025201066A1; JP2025127383A

Abstract

An air conditioner of the present invention is an air conditioner comprising an outdoor unit which exchanges heat between an outdoor air and a refrigerant, wherein the refrigerant is a flammable refrigerant, the outdoor unit includes a partition plate which divides a machine room and a space in which an outdoor fan is disposed (blower room), and the partition plate includes an opening portion through which the machine room and the space in which the outdoor fan is disposed (blower room) communicate with each other.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an air conditioner.

2. Description of the Related Art

In a suction-type heat pump system, a technique that rotates an outdoor fan in an opposite direction when leakage of a refrigerant is detected in a body of an outdoor unit has conventionally been known (see, for example, JP2002-115939A ). Specifically, this heat pump system uses dimethyl ether, which has flammability, as the refrigerant, and is configured to discharge the refrigerant from the body in which an absorber and a regenerator for the refrigerant are disposed by using the outdoor fan. Such a heat pump system allows the concentration of the refrigerant in the body to be less than a flammability limit.

SUMMARY OF THE INVENTION

Regarding recent air conditioners which are demanded to achieve both low GWP (Global Warming Potential) and low ODP (Ozone Depletion Potential) of refrigerants, those using a highly flammable refrigerant (R290: propane) have been practically used. Hence, it is necessary to consider countermeasures against leakage of a refrigerant in these air conditioners.
However, in an air conditioner utilizing a compression-type refrigeration cycle, an outdoor fan which promotes heat exchange between an outdoor air and a refrigerant is disposed in a separate section from that in which a compressor which generates heat is disposed, unlike the above-described suction type. Hence, in this air conditioner, it is impossible to reduce the amount of the refrigerant to be accumulated in a machine room in which the compressor is disposed in the outdoor fan, unlike the above-described heat pump system.
An object of the present invention is to provide an air conditioner which can reduce the amount of a refrigerant to be accumulated in a machine room.
An air conditioner of the present invention is an air conditioner comprising an outdoor unit which exchanges heat between an outdoor air and a refrigerant, wherein the refrigerant is a flammable refrigerant, the outdoor unit includes a partition plate which divides a machine room and a space in which an outdoor fan is disposed, and the partition plate includes an opening portion through which the machine room and the space in which the outdoor fan is disposed communicate with each other.
According to the present invention, it is possible to provide an air conditioner which can reduce the amount of a refrigerant to be accumulated in a machine room.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a configuration explanatory diagram of an air conditioner according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a state where a front plate and a top plate of an outdoor unit included in the air conditioner are removed.
FIG. 3 is a front view schematically representing the outdoor unit from which the front plate is removed.
FIG. 4 is a partially enlarged perspective view of an opening portion forming member provided in a partition plate of the outdoor unit.
FIG. 5A is a sectional view taken along VA-VA of FIG. 4.
FIG. 5B is a sectional view showing a modification of the opening portion forming member of FIG. 4.
FIG. 6 is a partially enlarged front view showing another modification of the opening portion forming member of FIG. 4.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, a mode for carrying out an air conditioner of the present invention (embodiment) will be described in detail with reference to the drawings as appropriate.
FIG. 1 is a configuration explanatory diagram of an air conditioner 100 according to the present embodiment.
As shown in FIG. 1, the air conditioner 100 includes an outdoor unit 101 which is installed outdoors and an indoor unit 102 which is installed indoors. The air conditioner 100 of the present embodiment is configured to include a compression-type refrigeration cycle using R290 (propane) as a refrigerant. However, the "refrigerant having flammability (flammable refrigerant)" in the air conditioner of the present invention is not limited to R290, and includes, for example, a single hydrocarbon (HC) refrigerant such as R170 (ethane), R1270 (propylene), or R600a (isobutane) and a HC mixed refrigerant of these. In addition, the refrigerant may be a fluorine-based refrigerant such as HFO-1234yf or R-32, or the like. Alternatively, the refrigerant may be a mixed refrigerant of these refrigerants. A flammable refrigerant includes a mildly flammable or highly flammable refrigerant. Moreover, in the present embodiment, as the refrigerant, a refrigerant having a specific gravity larger than the air is favorably used.
The air conditioner 100 during the cooling operation takes in a liquid refrigerant (including a gas-liquid two-phase refrigerant), which flows in a heat-transfer tube of an indoor heat exchanger, which is not shown, in the indoor unit 102 from the outdoor unit 101 through a liquid pipe 20. At this time, the indoor heat exchanger (not shown) functions as an evaporator to cool down the surrounding air (indoor air). Then, the gas refrigerant evaporated in the indoor heat exchanger is sent to the outdoor unit 101 through a gas pipe 30.
In addition, the air conditioner 100 during the heating operation sends a gas refrigerant of high temperature and high pressure from a compressor 7 (see FIG. 2), which will be described later, to the indoor unit 102 through the gas pipe 30 by switching the refrigerant flow passage by a four-way valve, which is not shown, of the outdoor unit 101. At this time, the above-described indoor heat exchanger (not shown) functions as a condenser to heat the surrounding air (indoor air). Then, the liquid refrigerant (including a gas-liquid two-phase refrigerant) condensed in the heat-transfer tube (not shown) of this indoor heat exchanger is sent to the outdoor unit 101 through the liquid pipe 20.
Next, the outdoor unit 101 will be described in further detail.
As shown in FIG. 1, a body 1 of the outdoor unit 101 is configured to include a front plate 1a, a side plate 1b, and a top plate 1c.
In the front plate 1a, a circular opening 1a1 is formed to correspond to an outdoor fan 9 (see FIG. 2), which will be described later. To this opening 1a1, a fan grill 1a2 is attached.
FIG. 2 is a perspective view showing a state where the front plate 1a (see FIG. 1) and the top plate 1c (see FIG. 1), which are included in the body 1 of the outdoor unit 101, are removed.
As shown in FIG. 2, inside the outdoor unit 101, the outdoor fan 9, the compressor 7, an accumulator 4, and an outdoor heat exchanger 3 are disposed.
Specifically, the inside of the outdoor unit 101 is partitioned into a blower room 5b and a machine room 5a by a partition plate 2 including an opening portion forming member 11, which will be described in detail later. Then, the outdoor fan 9 is disposed in the blower room 5b, and the compressor 7 and the accumulator 4 are disposed in the machine room 5a.
In FIG. 2, reference sign S is a refrigerant concentration detecting sensor, which is disposed in the machine room 5a near the opening portion forming member 11.
In addition, the outdoor heat exchanger 3 is disposed to extend from the blower room 5b to the machine room 5a along the side plate 1b and a back surface (rear surface) of the outdoor unit 101. Note that a suction portion (not shown) for an outdoor air to the inside of the outdoor unit 101 is formed in the side plate 1b and the back surface (rear surface) of the outdoor unit 101.
The outdoor heat exchanger 3 during the cooling operation functions as a condenser to send the liquid refrigerant (including a gas-liquid two-phase refrigerant) to the indoor unit 102 (see FIG. 1) through the liquid pipe 20 (see FIG. 1) again. The outdoor heat exchanger 3 during the heating operation functions as an evaporator to send the gas refrigerant from the compressor 7 to the indoor unit 102 through the gas pipe 30 (see FIG. 1) again. Note that the accumulator 4 separates a gas refrigerant from the liquid refrigerant in the gas-liquid two-phase refrigerant sent therein through the liquid pipe 20 (see FIG. 1), and sends the gas refrigerant to the compressor 7.
The outdoor fan 9 rotates to send the air such that the outdoor heat exchanger 3 is located on the upwind side and the fan grill 1a2 (see FIG. 1) is located on the downwind side. Specifically, the outdoor fan 9 rotates clockwise in the front view of the outdoor unit 101 as described later. In this way, the outdoor fan 9 causes an outdoor air, which is sucked from the above-described suction portion (not shown) into the outdoor unit 101, to flow to the outdoor heat exchanger 3, and promotes heat exchange between the refrigerant flowing through the outdoor heat exchanger 3 and the outdoor air.
As shown in FIG. 2, an electric component box assembly 8 is provided inside of an upper portion of the body 1. The electric component box assembly 8 includes an electric component box 8a, a control board 8b, and a board support 8c. The control board 8b forms a control unit (not shown) which centrally controls the air conditioner 100 (see FIG. 1). The board support 8c supports the control board 8b on the lower surface side. On the right end portion of the electric component box 8a, a terminal block for power supply, which is not shown, is provided.
Next, the partition plate 2 (see FIG. 2) will be described.
FIG. 3 is a front view schematically representing the outdoor unit 101 from which the front plate 1a (see FIG. 1) is removed. Note that in FIG. 3, the description of the compressor 7 (see FIG. 2), the accumulator 4 (see FIG. 2), and the outdoor heat exchanger 3 (see FIG. 2) is omitted for convenience of illustration.
As shown in FIG. 3, the partition plate 2 is formed of a bent plate member, and extends in an upper-lower direction to face a space on the outdoor fan 9 side and a space on the compressor 7 side in a left-right direction. On a lower portion of the partition plate 2, the opening portion forming member 11, which will be described in detail later, is attached.
As shown in FIG. 3, the partition plate 2 in the present embodiment is bent to form a step in the left-right direction. Specifically, the partition plate 2 includes a first plate member 2a which extends in the upper-lower direction in an upper portion inside the body 1 of the outdoor unit 101, a third plate member 2c which extends in the upper-lower direction in a lower portion inside the body 1 while being displaced in the right direction from the first plate member 2a, and a second plate member 2b which extends while being inclined to connect a lower edge of the first plate member 2a and an upper edge of the third plate member 2c in a middle portion inside the body 1.
Then, as described above, the partition plate 2 partitions the inside of the outdoor unit 101 to form the machine room 5a between the partition plate 2 and the side plate 1b on the right side.
In addition, the second plate member 2b of the partition plate 2 forms a space portion 5a1 (machine room space portion) in which a horizontal sectional area A gradually decreases toward the lower side between the second plate member 2b and the side plate 1b on the right side above the opening portion forming member 11.
Next, the opening portion forming member 11 (see FIG. 2) will be described.
FIG. 4 is a partially enlarged perspective view of the opening portion forming member 11. FIG. 4 shows the opening portion forming member 11 as viewed obliquely upward from a front lower portion of the blower room 5b (see FIG. 2).
As shown in FIG. 4, the opening portion forming member 11 has a louver shape. That is, the opening portion forming member 11 includes a wall plate 12, a plurality of slits 13 which are formed in this wall plate 12 and are long in a front-rear direction, and slats 14 which cover the respective slits 13 from above to form opening portions 10 opening downward.
Note that the slits 13 in the present embodiment are arranged in a plurality of rows (specifically, two rows) in the front-rear direction and in a plurality of rows (specifically, eight rows) in the upper-lower direction. However, the number and arrangement of the slits 13 are not limited to this.
FIG. 5A is a sectional view taken along VA-VA of FIG. 4.
As shown in FIG. 5A, the slat 14 of the opening portion forming member 11 which forms the louver shape is supported on an upper edge of the slit 13 formed in the wall plate 12. In addition, the slat 14 is bent and extends downward in a vertical direction in the middle of extending from the wall plate 12 to the blower room 5b side.
Then, blades 9a (see FIG. 3) of the outdoor fan 9 (see FIG. 3) which rotates clockwise as described above pass downward from above the slat 14 as indicated by an open arrow in FIG. 5A.
In addition, a lower edge of the slat 14 forms the opening portion 10 which faces downward between the lower edge of the slat 14 and a lower edge of the slit 13 in a left-right width W1. This opening portion 10 is formed to be laterally long in a front-rear width W2 as shown in FIG. 4. Such an opening portion 10 allows the blower room 5b and the machine room 5a to communicate with each other through the slit 13.
Then, the gap of the left-right width W1 in the opening portion 10 in the present embodiment is set to be less than a quenching distance. This left-right width W1 is set to be less than 1.5 mm.
The opening portion 10 set in such left-right width W1 exhibits a quenching effect regardless of whether the front-rear width W2 (see FIG. 4) of the opening portion 10 is long or short.
FIG. 5B is a sectional view showing a modification of the opening portion forming member 11 of FIG. 4.
As shown in FIG. 5B, the slat 14 of the opening portion forming member 11 according to the modification is supported on the wall plate 12 at the upper edge of the slit 13, and is inclined to gradually displace to the blower room 5b side toward the lower side. That is, the slat 14 of the opening portion forming member 11 is formed to extend obliquely downward in the vertical direction.
In addition, the lower edge of the slat 14 forms the opening portion 10 which faces downward between the lower edge of the slat 14 and the lower edge of the slit 13 in the left-right width W1.
In addition, this opening portion 10 is formed to be laterally long in the front-rear width W2 as shown in FIG. 4.
Then, the gap of the left-right width W1 in the opening portion 10 in the present embodiment is set to be less than a quenching distance. This left-right width W1 is set to be less than 1.5 mm.
Note that in FIG. 5B, an open arrow indicates a direction of movement of the blades 9a (see FIG. 3) of the rotating outdoor fan 9 (see FIG. 3).
Note that the opening portion forming member 11 according to this modification allows the left-right width W1 of the opening portion 10 to be adjusted by adjusting the angle of inclination of the slat 14.
Referring back to FIG. 3, in the outdoor unit 101, a refrigerant concentration detecting sensor S is disposed to be adjacent to the opening portion 10 of such an opening portion forming member 11.
The refrigerant concentration detecting sensor S is not particularly limited as long as the refrigerant concentration detecting sensor S can detect the concentration of propane gas, and for example, a thermal conductive gas sensor or another sensor can be used.
The refrigerant concentration detecting sensor S in the present embodiment outputs a detection signal of propane gas to the control board 8b of the electric component box assembly 8 through a signal line L1. A control unit (not shown) specified in the control board 8b determines whether or not the concentration of propane gas in the machine room 5a is higher than a predetermined threshold based on the detection signal of propane gas from the refrigerant concentration detecting sensor S. Then, if this control unit determines that the concentration of propane gas is higher than the threshold, the control unit outputs an alarm sending instruction to an alarm sending circuit (not shown) of the indoor unit 102 through a signal line L2 shown in FIG. 1. The alarm sending circuit (not shown) causes an alarm display unit 102a including an alarm lamp and the like of the indoor unit 102 to display information that the refrigerant is leaking in the outdoor unit 101.

Next, advantageous effects achieved by the air conditioner 100 of the present embodiment will be described.
The air conditioner 100 of the present embodiment includes the indoor unit 102 which exchanges heat between an indoor air and a refrigerant, and the outdoor unit 101 which exchanges heat between an outdoor air and the refrigerant, in which the refrigerant has flammability, the outdoor unit 101 includes the partition plate 2 which divides the machine room 5a and the space (blower room 5b) in which the outdoor fan 9 is disposed, and the partition plate 2 includes the opening portion 10 through which the machine room 5a and the space (blower room 5b) in which the outdoor fan 9 is disposed communicate with each other.
According to such an air conditioner 100, the amount of the flammable refrigerant to be accumulated in the machine room 5a can be reduced by the opening portion 10 communicating with the space (blower room 5b) in which the outdoor fan 9 is disposed. The air inside the machine room 5a can be drawn through the opening portion 10 by the rotation of the outdoor fan 9. This can prevent the accumulation. This allows the air conditioner 100 to prevent combustion of the refrigerant inside the machine room 5a even if the refrigerant leaked inside the machine room 5a.
In addition, in this air conditioner 100, the refrigerant is R290, and the opening portion 10 is provided in a lower portion of the partition plate 2 in the vertical direction.
According to such an air conditioner 100, R290 (propane gas), which is heavier than the air, can be efficiently discharged from the machine room 5a through the opening portion 10 which is provided in the lower portion of the partition plate 2.
In addition, in this air conditioner 100, the refrigerant is R290, and the gap (left-right width W1) of the opening portion 10 is set to be less than the quenching distance of propane (less than 1.5 mm).
According to such an air conditioner 100, the spread of fire to the blower room 5b side could be suppressed even if the refrigerant accumulated in the machine room 5a were ignited. In addition, even if the refrigerant discharged from the machine room 5a to the blower room 5b side reached the flammability limit concentration or more and the refrigerant accumulated on the blower room 5b side is ignited, the spread of fire to the machine room 5a side could be prevented.
In addition, in this air conditioner 100, the opening portion 10 is provided in the opening portion forming member 11 having a louver shape, and the slat 14 of the opening portion forming member 11 which forms the louver shape extends downward or obliquely downward in the vertical direction to form the opening portion 10 which opens downward.
According to such an air conditioner 100, when rainwater enters the blower room 5b, entry of the rainwater into the machine room 5a through the opening portion 10 can be suppressed.
In addition, in this air conditioner 100, the direction of rotation of the outdoor fan 9 is set such that the blade 9a of the outdoor fan 9 passes downward from above the slat 14.
According to such an air conditioner 100, water droplets of rainwater which has entered the blower room 5b are forcibly guided to pass downward from above the slat 14 by the air flow of the blade 9a of the rotating outdoor fan 9. This makes it possible to more effectively suppress the entry of rainwater into the machine room 5a through the opening portion 10.
In addition, this air conditioner 100 further includes the refrigerant concentration detecting sensor S inside the body 1 of the outdoor unit 101, wherein the refrigerant concentration detecting sensor S is disposed to be adjacent to the opening portion 10.
According to such an air conditioner 100, since the refrigerant concentration detecting sensor S is disposed to be adjacent to the opening portion 10, which is also a discharge passage (passage) of the leaked refrigerant from the machine room 5a, the detection sensitivity for the refrigerant is further improved.
In addition, in this air conditioner 100, the refrigerant is R290, and the air conditioner 100 includes, above the opening portion 10, the space portion 5a1 (machine room space portion) in which the horizontal sectional area A of the machine room 5a gradually decreases toward the lower side.
According to such an air conditioner 100, even if the refrigerant were leaked in the machine room 5a, the accumulation region of R290 (propane gas), which is heavier than the air, would be narrowed as R290 (propane gas) moves downward. The refrigerant R290 is efficiently discharged from the machine room 5a through the opening portion 10.

Modified Embodiment

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiments, and can be implemented in various forms.
In the above-described embodiments, the opening portion forming member 11 having a louver shape has been described. However, the opening portion forming member 11 is not limited to one having a louver shape.
FIG. 6 is a configuration explanatory diagram of an opening portion forming member 11 formed from a mesh member 15.
As shown in FIG. 6, the mesh member 15 takes a net structure having opening portions 15a each of which has a rhombus shape long in the front-rear direction in a front view when the opening portion forming member 11 is viewed in the left-right direction (the direction perpendicular to the sheet surface of FIG. 6).
Specifically, the opening portion 15a has a rhombus shape in which a lateral width W4 is longer than a vertical width W3.
Then, the vertical width W3 of the opening portion 15a in the present embodiment is set to be less than the quenching distance, that is, less than 1.5 mm.
The opening portion 15a set in such a vertical width W3 exhibits a quenching effect regardless of whether the lateral width W4 of the opening portion 15a is long or short.
In addition, the net shape of the mesh member 15 is not limited to a rhombus shape, and may be a rectangle shape (including a square shape) or another shape.
In particular, a mesh member having a rectangular net formed by flat-weaving a very thin metal wire is preferable because a commercially-available product can be used.
In addition, although not shown in the drawings, the opening portion forming member 11 may be formed of a punching metal having a plurality of small pores each having a quenching diameter of less than 1.5 mm.
The opening portion forming member 11 formed of such a mesh member can also prevent insects from entering the machine room 5a.
In addition, although the opening portions 10 in the above-described embodiments are formed in the opening portion forming member 11, the opening portions 10 can be formed directly in the partition plate 2.
In addition, the size of the opening portions 10 may be set to exceed the quenching distance or the quenching diameter for the purpose of improving the speed of reduction of the gas refrigerant in the machine room 5a.

Claims

An air conditioner comprising an outdoor unit which exchanges heat between an outdoor air and a refrigerant, wherein
the refrigerant is a flammable refrigerant,

the outdoor unit includes a partition plate which divides a machine room and a space in which an outdoor fan is disposed, and

the partition plate includes an opening portion through which the machine room and the space in which the outdoor fan is disposed communicate with each other.
The air conditioner according to claim 1, wherein the opening portion is provided in a lower portion of the partition plate in a vertical direction.
The air conditioner according to claim 1 or 2, wherein a gap of the opening portion is set to be less than a quenching distance of the flammable refrigerant.
The air conditioner according to at least claims 1 to 3, wherein
the opening portion is provided in an opening portion forming member having a louver shape, and

a slat of the opening portion forming member which forms the louver shape extends downward or obliquely downward in a vertical direction to form an opening portion which opens downward.
The air conditioner according to claim 4, wherein a direction of rotation of the outdoor fan is set such that a blade of the outdoor fan passes downward from above the slat.
The air conditioner according to at least claims 1 to 5, further comprising a refrigerant concentration detecting sensor inside a body of the outdoor unit, wherein
the refrigerant concentration detecting sensor is disposed to be adjacent to the opening portion.
The air conditioner according to at least claims 1 to 6, comprising, above the opening portion, a machine room space portion in which a horizontal sectional area of the machine room gradually decreases toward a lower side.