JP6477126B2 - Floor-mounted air conditioning indoor unit - Google Patents

Description

  The present invention relates to a floor-standing air-conditioning indoor unit, and more particularly to a floor-standing air-conditioning indoor unit that uses a flammable refrigerant having a specific gravity greater than that of air.

  In an air conditioner that uses a flammable refrigerant, there is a risk of causing an ignition accident if there is an ignition source in the vicinity of the leaked flammable refrigerant when the flammable refrigerant leaks. In particular, when the indoor unit of the air conditioner is a floor-standing type, the leaked refrigerant is likely to stay on the floor when a refrigerant leaks. Increased risk of accidents.

  As a method for avoiding an ignition accident caused by refrigerant leakage, for example, as described in Patent Document 1 (Japanese Patent No. 4639451), leakage of the refrigerant is detected by a sensor, and the leakage of the refrigerant is notified by an alarm. Or a circuit in which the refrigerant leaks is cut off. Further, for example, as described in Patent Document 2 (Japanese Patent No. 3810960), ventilation is performed when the sensor detects that the refrigerant has leaked, thereby avoiding an ignition accident by preventing the flammable concentration from being reached. There is a way to do it.

Japanese Patent No. 4639451 Japanese Patent No. 3810960

  As described above, in order to issue an alarm when a refrigerant leaks, shut off a circuit, or perform ventilation, it is assumed that the refrigerant has been leaked. When detection by such a sensor is a prerequisite, a control circuit including the sensor is required, and the air-conditioned room unit becomes expensive. Moreover, when the leakage of the flammable refrigerant cannot be detected by the sensor, there is a possibility that the method for avoiding the ignition accident does not work well and the risk cannot be reduced.

  The present invention has been made in view of such circumstances, and provides a floor-mounted air-conditioning indoor unit that can reduce the risk of a fire accident due to refrigerant leakage without detecting refrigerant leakage. It is an object.

(1) A floor-standing air-conditioning indoor unit (hereinafter, also simply referred to as “air-conditioning indoor unit”) of the present invention is a floor-standing air-conditioning indoor unit that uses a flammable refrigerant having a specific gravity greater than that of air. A housing having a suction port for sucking indoor air at the bottom, where at least a part of the suction port is located at a position lower than the height of 500 mm from the floor, and a suction port opening and closing for opening and closing the suction port of the housing A suction port opening / closing mechanism that opens the suction port when the operation is continued and closes the suction port when the operation is stopped.

  According to the air-conditioning indoor unit of the present invention, since the combustible refrigerant is heavier than air, even if the combustible refrigerant leaks in the casing of the air intake indoor unit with the lower suction, the flammable refrigerant is confined or enclosed in the casing. It is possible to leak from a relatively high place such as a body outlet. Therefore, since the ignition source does not normally exist in the casing of the air-conditioning indoor unit, the risk of fire is kept low even if the leaked combustible refrigerant fills the casing. In addition, even if the combustible refrigerant filled in the casing leaks from a relatively high place such as an outlet, the combustible refrigerant is diffused by the time it falls to the floor. Reaching the flammable concentration above can be suppressed.

(2) In the air conditioning indoor unit of (1) above, the housing has an air outlet at the top for blowing conditioned air into the room, and the lower end of the air outlet is located at a height of 1500 mm or more from the floor surface. It can be. In this case, when the leaked combustible refrigerant fills the air-conditioning indoor unit and the refrigerant overflows into the room from the air outlet, the refrigerant flows down from the air outlet toward the floor. Since the flammable refrigerant leaked from a height of 1500 mm or more flows down, the diffusion effect of the refrigerant is enhanced.

(3) In the air conditioning indoor unit of (2) above, the casing can be configured so that the outlet does not close when operation is stopped. In this case, by opening the air outlet during the operation stop and actively overflowing the leaked flammable refrigerant filled in the housing from the lower end of the air outlet located at a height of 1500 mm or more from the floor surface, Reaching the flammable concentration can be suppressed by using the diffusion effect of the flammable refrigerant flowing down from above.

(4) The air conditioning indoor unit of (2) further includes a blower opening / closing mechanism that opens and closes the blower outlet of the housing, and the blower opening / closing mechanism opens the blower outlet when the operation is continued and closes the blower outlet when the operation is stopped. , Can be. In this case, the large opening of the housing can be eliminated by closing the suction port and the air outlet when the operation is stopped. For example, if the refrigerant leakage is very small, the refrigerant that leaks during the operation is confined in the housing and the operation is started. Later it can be diffused into the room.

(5) In the air-conditioning indoor units of (1) to (4) above, the suction opening / closing mechanism has a plurality of opening / closing members, and when the operation is stopped, the plurality of opening / closing members are overlapped with each other to close the suction opening of the housing. Can be. In this case, the gap when the suction port is closed can be reduced by overlapping a plurality of opening and closing members and closing the suction port, and the amount of leakage refrigerant leaking from the suction port is reduced to leak the combustible refrigerant Can be prevented from reaching a flammable concentration indoors.

(6) The air-conditioning indoor unit of (1) to (5) further includes a fan air outlet opening / closing mechanism that opens and closes a fan air outlet of an indoor fan disposed in a lower region in the housing, and the fan air outlet opening / closing mechanism May open the fan outlet when the operation is continued and close the fan outlet when the operation is stopped. In this case, by closing the fan air outlet opening / closing mechanism that opens and closes the fan air outlet of the indoor fan when the operation is stopped, even if the refrigerant leaks from the heat exchanger, the leaked refrigerant passes through the fan air outlet. It can be prevented that it reaches the lower region of the body and further leaks into the room through the suction port or the like. By closing the inlet when the operation is stopped, leakage of refrigerant from the lower area of the housing to the room can be almost prevented, but by further closing the fan outlet, the refrigerant leaked more reliably from the heat exchanger. Can be prevented from leaking into the room.

(7) In the air conditioning indoor unit of (6), the fan air outlet opening / closing mechanism includes a rectangular closing plate capable of closing the fan air outlet, a rotating shaft provided with one side edge of the closing plate, and a rotating shaft. And a motor having a tip of the rotating shaft connected to one end of the rotating shaft. In this case, the fan outlet can be opened and closed with a simple configuration in which the closing plate is driven by a motor.

  According to the air conditioning indoor unit of the present invention, the flammable refrigerant leaked on the floor of the room has a simple configuration in which the suction port opening / closing mechanism opens the suction port when the operation is continued and closes the suction port when the operation is stopped. Can be suppressed, and the risk of a fire accident due to the leakage of the combustible refrigerant can be reduced without detecting the leakage of the combustible refrigerant.

It is a circuit diagram which shows the outline | summary of the air conditioning apparatus to which the air-conditioning indoor unit of this invention is applied. It is a block diagram which shows the outline of a structure of the control system of the air conditioning apparatus shown by FIG. It is a front view of one Embodiment of the air-conditioning indoor unit of this invention. It is a perspective view of the air-conditioning indoor unit shown by FIG. It is sectional drawing of the air-conditioning indoor unit shown by FIG. (A) is the elements on larger scale of the suction inlet periphery at the time of the operation stop of the air-conditioning indoor unit shown by FIG. 3, (b) is the II sectional view taken on the line of FIG. 6 (a). (A) is the elements on larger scale of the suction inlet periphery at the time of the driving | running operation of the air-conditioning indoor unit shown by FIG. 3, (b) is the II-II sectional view taken on the line of Fig.7 (a). (A) is a plane explanatory view of the fan outlet opening and closing mechanism in the air conditioning indoor unit shown in FIG. 3, (b) is a perspective explanatory view when the fan outlet is opened. It is a flowchart for demonstrating control of the suction inlet opening-and-closing mechanism and wind direction adjustment mechanism which concern on 1st Embodiment. It is a flowchart for demonstrating control of the suction inlet opening-and-closing mechanism and wind direction adjustment mechanism which concern on 2nd Embodiment.

Hereinafter, an embodiment of an air-conditioning indoor unit of the present invention will be described in detail with reference to the accompanying drawings.
<First Embodiment>
(1) Overall Configuration The overall configuration of the air conditioning indoor unit according to the first embodiment of the present invention will be described. FIG. 1 is a circuit diagram showing an outline of an air conditioner. As shown in FIG. 1, the air conditioning indoor unit 20 installed in the indoor RS is connected to the air conditioning outdoor unit 30 to constitute the air conditioner 10. In FIG. 1, a solid line connecting the devices represents a refrigerant pipe, and a broken line connecting the devices represents a signal transmission line.

  The air conditioning indoor unit 20 is connected to the air conditioning outdoor unit 30 installed outside by a refrigerant pipe, and constitutes a refrigerant circuit of the air conditioner 10 together with the air conditioning outdoor unit 30. For this purpose, the air conditioning indoor unit 20 and the air conditioning outdoor unit 30 are connected to each other by a communication pipe 12 through which a refrigerant pipe, a communication line, a transmission line, and the like pass. In the annular refrigerant circuit shown in FIG. 1, the indoor heat exchanger 21 of the air conditioning indoor unit 20, the compressor 31 of the air conditioning outdoor unit 30, the four-way switching valve 32, the outdoor heat exchanger 33, the electric valve 34, and An accumulator 35 and the like are connected in series.

  A four-way switching valve 32 is connected to the discharge side of the compressor 31 in order to switch the direction of the flow of the refrigerant flowing in the refrigerant circuit between the cooling operation and the heating operation. The four-way switching valve 32 is switched to a path indicated by a solid line during cooling, while the four-way switching valve 32 is switched to a path indicated by a broken line during heating.

  During cooling, the refrigerant compressed and discharged by the compressor 31 is sent to the outdoor heat exchanger 33 via the four-way switching valve 32. During the cooling, the outdoor heat exchanger 33 functions as a condenser, and the refrigerant that has been deprived of heat by exchanging heat with the outside air by condensation of the refrigerant is sent from the outdoor heat exchanger 33 to the motor-operated valve 34. The motor-operated valve 34 functions as an expansion valve, and the high-pressure liquid refrigerant changes to a low-pressure wet steam state. Thus, the refrigerant expanded by the electric valve 34 enters the indoor heat exchanger 21 through the refrigerant communication pipe 12a. During the cooling, the indoor heat exchanger 21 functions as an evaporator, and heat is exchanged between the indoor air and the refrigerant due to the evaporation of the refrigerant. It passes through the switching valve 32 and is sent to the accumulator 35 connected to the suction side of the compressor 31.

  During heating, the refrigerant compressed and discharged by the compressor 31 is sent from the four-way switching valve 32 to the indoor heat exchanger 21 that functions as a condenser via the refrigerant communication pipe 12b. And the refrigerant | coolant which came out of the outdoor heat exchanger 33 which functions as an evaporator along the path | route reverse to the time of air_conditioning | cooling is sent to the compressor 31 via the accumulator 35. FIG. That is, at the time of heating, from the compressor 31, the four-way switching valve 32, the refrigerant communication pipe 12 b, the indoor heat exchanger 21, the refrigerant communication pipe 12 a, the electric valve 34, the outdoor heat exchanger 33, the four-way switching valve 32, and the accumulator 35. The refrigerant circulates in a path that goes back to the compressor 31 in order.

  The air-conditioning indoor unit 20 and the air-conditioning outdoor unit 30 include an indoor fan 22 for sending indoor air to the indoor heat exchanger 21 and outdoor heat in order to promote heat exchange in the indoor heat exchanger 21 and the outdoor heat exchanger 33, respectively. A propeller fan 37 that sends outside air to the exchanger 33 is provided. The indoor fan 22 and the propeller fan 37 have an indoor fan motor 22m and an outdoor fan motor 37m that rotate the impeller and the propeller, respectively.

(2) Control System FIG. 2 is a block diagram showing an outline of the configuration of the control system. In order to perform the air conditioning operation in the air conditioning apparatus 10 correctly and efficiently, the air conditioning apparatus 10 is controlled by the control device 60 shown in FIG. The control device 60 includes an indoor control device 61 and an outdoor control device 62. The indoor control device 61 is incorporated in the air-conditioned indoor unit 20, and the outdoor control device 62 is incorporated in the air-conditioned outdoor unit 30. The indoor control device 61 and the outdoor control device 62 are connected to each other via the communication line 12c and transmit / receive data to / from each other. The indoor control device 61 and the outdoor control device 62 are configured to include a CPU (Central Processing Unit), a memory, a peripheral circuit, and the like.

  The air conditioning indoor unit 20 is provided with various temperature sensors 24 to 26 for measuring the temperature of the indoor heat exchanger 21 and room air. The temperature values measured by these temperature sensors 24 to 26 are transmitted to the indoor control device 61. The indoor control device 61 controls the indoor fan motor 22m, the wind direction adjusting mechanism 80, and the like based on the temperature values detected by the temperature sensors 24 to 26, so that the refrigerant in the air conditioning indoor unit 20 of the air conditioner 10 is obtained. The circuit is operated. The indoor control device 61 also controls the inlet opening / closing mechanism 70 and the fan outlet opening / closing mechanism 91 of the air conditioning indoor unit 20.

  Furthermore, in order to measure the temperature of each part of the air-conditioning outdoor unit 30, the temperature sensors 41 to 45 are also provided in the air-conditioning outdoor unit 30. In addition, the air-conditioning outdoor unit 30 is provided with pressure sensors 46 and 47 and the like for measuring the refrigerant pressure. Information regarding the temperature value, pressure value, and presence / absence of leakage of the refrigerant measured by each of the sensors 41 to 47 is transmitted to the outdoor control device 62. The outdoor control device 62 has a compressor motor unit 38, a four-way switching valve 32, a motor operated valve 34, By controlling the outdoor fan motor 37m, the refrigerant circuit in the air conditioning outdoor unit 30 of the air conditioner 10 is operated.

(3) Detailed configuration (3-1) Refrigerant The refrigerant flowing through the indoor heat exchanger 21 in the air conditioning indoor unit 20 is a combustible refrigerant having a specific gravity greater than that of air. Here, the case where R32 refrigerant is used as the refrigerant flowing through the indoor heat exchanger 21 will be described, but the present invention is not limited to this, and for example, R1234yf, R717 (ammonia), R290 (propane) The same applies to the refrigerant as a mixture thereof or a mixture thereof with R32. The R32 refrigerant is sometimes called a slightly flammable refrigerant, but here, what is called a slightly flammable refrigerant is also classified as a flammable refrigerant. Even if the R32 refrigerant leaks in the room RS, the R32 refrigerant does not burn unless the concentration in the air reaches a flammable concentration, and there is a lower limit and an upper limit in the combustion range in which the R32 refrigerant causes combustion. That is, when the concentration of the leaked R32 refrigerant in the air is lower than the lower limit of the combustion range, the R32 refrigerant does not burn even if there is fire. Further, when the concentration of the leaked R32 refrigerant in the air is higher than the upper limit of the combustion range, the R32 refrigerant does not burn even if there is a fire.

  Further, the R32 refrigerant has a low combustion speed and a low heat of combustion per unit weight, and therefore does not cause explosive combustion like propane. Thus, R32 refrigerant can be said to be a relatively safe refrigerant with almost no risk of fire even if leakage occurs, compared to a refrigerant having high combustibility such as propane. However, it is preferable that safety measures are applied to equipment using R32 refrigerant to further reduce the risk of fire and the like.

  By the way, since the R32 refrigerant is colorless and odorless, it is usually difficult for a person to detect the leakage of the R32 refrigerant even if there is a person in the room RS when the R32 refrigerant leaks in the room RS. When the R32 refrigerant leaks from the air-conditioned indoor unit 20 and leaks into the indoor RS outside the air-conditioned indoor unit 20, if the air-conditioned indoor unit 20 stops and the indoor RS is in a windless state, the floor FF (FIG. 3) The concentration of the R32 refrigerant gradually increases from the lower space close to (see), and the portion with the higher concentration spreads from the lower space close to the floor surface FF toward the upper portion. Therefore, if the air-conditioning indoor unit 20 is in a windless state, when the leakage of the R32 refrigerant starts, the flammable concentration is reached first from the lower space close to the floor surface FF, and when the leakage continues, from the lower space close to the floor surface FF. First, the concentration becomes higher than the upper limit of the combustion range.

  Normally, considering the amount of R32 refrigerant used in the air conditioner 10, if an air flow is generated in the room RS, the leaked R32 refrigerant is diffused and uniformed throughout the room RS. Reaching flammable concentrations is unlikely. Therefore, what is effective in reducing the risk is to take measures to prevent the R32 refrigerant leaking into the room RS from reaching the flammable concentration when the air-conditioned room unit 20 is stopped. Hereinafter, the configuration of the air-conditioned room unit 20 in which such measures are taken will be described.

(3-2) Air Conditioning Indoor Unit The configuration of the air conditioning indoor unit 20 will be described in detail with reference to FIGS. 3 to 5. 3 is a front view showing the appearance of the air-conditioned room unit 20, FIG. 4 is a perspective view showing the appearance of the air-conditioned room unit 20, and FIG. 5 is a schematic cross section for explaining the inside of the air-conditioned room unit 20. FIG. As can be seen from FIG. 4, the air-conditioned indoor unit 20 includes a casing 50 that is a substantially rectangular parallelepiped casing. In the description in this specification, the vertical and vertical directions, The left-right direction is assumed to be the direction indicated by the arrows in FIG.

  The casing 50 has six surfaces including a front surface 51, a right side surface 52, a left side surface 53, a rear surface 54, a top surface 55, and a bottom surface 56. The air conditioning indoor unit 20 is a floor-standing type, and usually the bottom surface 56 is in contact with the floor surface FF. In order to connect the communication pipe 12 shown in FIG. 1 to the air conditioning indoor unit 20, a communication pipe through hole (not shown) is formed in the rear surface 54 of the air conditioning indoor unit 20. However, the through-hole for connecting piping on the rear surface 54 is closed with a heat insulating material or a putty (not shown). Similarly, the right side surface 52, the left side surface 53, the top surface 55, and the bottom surface 56 have no openings and through holes. Even if the R32 refrigerant leaks inside the air conditioning indoor unit 20, the right side surface 52, the left side surface 53, and the rear surface. 54, it does not leak into the room RS from the top surface 55 and the bottom surface 56 side.

  The front surface 51 of the air conditioning indoor unit 20 is provided with a suction port 28 in the lower part and a blower outlet 29 in the upper part. A filter (not shown) is attached behind the suction port 28. The height h2 from the floor surface FF of the opening lower end portion 28a of the suction port 28 is set to be less than 500 mm, and at least a part of the suction port 28 is disposed at a position lower than the height position of 500 mm from the floor surface FF. It has become. Moreover, the height h4 from the floor surface FF of the opening lower end portion 29a of the air outlet 29 of the air conditioning indoor unit 20 is set to 1500 mm or more. In the air conditioning indoor unit 20, the total height h1 is about 1850 mm, whereas the height h2 of the opening lower end portion 28a of the suction port 28 from the floor surface FF is about 100 mm, and from the floor surface FF of the opening upper end portion 28b. The height h3 is about 800 mm. The height h4 from the floor FF of the opening lower end 29a of the air outlet 29 of the air conditioning indoor unit 20 is about 1550 mm, and the height h5 of the opening upper end 29b from the floor FF is about 1800 mm.

  An operation panel 65 is disposed on the front surface 51 of the air conditioning indoor unit 20 between the suction port 28 and the air outlet 29. By operating the operation panel 65, the user can input various instructions to the control device 60. On the rear side of the operation panel 65, an electrical component box 66 is disposed. Although an electrical circuit is housed in the electrical component box 66, the electrical component box 66 is covered with a casing. Therefore, even if the R32 refrigerant reaches a flammable concentration in the air conditioning indoor unit 20, the electrical component box 66 is not an ignition source. In addition, as shown in FIG. 5, an indoor heat exchanger 21 and an indoor fan 22 are installed inside the air-conditioned indoor unit 20, and these also have R32 refrigerant in the combustible concentration in the air-conditioned indoor unit 20. Will not be an ignition source. That is, in the air conditioning indoor unit 20, there is no ignition source for the R32 refrigerant having a combustible concentration in the air conditioning indoor unit 20.

(3-3) Suction Port FIG. 6 (a) shows the state of the suction port 28 when the operation of the air conditioning indoor unit 20 is stopped, and FIG. 6 (b) shows II of FIG. 6 (a). A part of the suction port 28 cut by a line is shown enlarged. 7A shows the state of the suction port 28 when the air-conditioning indoor unit 20 continues to be operated, and FIG. 7B shows the suction cut along the line II-II in FIG. 7A. A portion of the mouth 28 is shown enlarged.

  A plurality of blades 71 extending in the left-right direction are arranged side by side in the vertical direction at the suction port 28. Each of the plurality of blades 71 is provided with a rotation shaft 72, and each blade 71 stands vertically with the rotation shaft 72 as a rotation center (see FIG. 6B) and horizontally tilts (see FIG. 7). It is configured to be able to take two states (see (b)). For this purpose, the plurality of blades 71 are all connected to the interlocking plate 73, and when the interlocking plate 73 is moved downward, the blade 71 stands vertically and the suction port 28 is closed. In the state of FIG. 6B, the blades 71 adjacent vertically are configured to overlap each other in the region Ar1. Then, when the interlocking plate 73 moves upward in the state of FIG. 7B, the blade 71 falls down horizontally and the suction port 28 is opened.

  The operation of moving the interlocking plate 73 up and down is performed by a suction port opening / closing mechanism 70 (see FIG. 2) using a stepping motor (not shown). The suction opening / closing mechanism 70 closes the suction opening 28 of the casing 50 by stacking a plurality of blades 71 on each other when the operation is stopped. The suction opening / closing mechanism 70 is controlled by the indoor control device 61.

(3-4) Air outlet The air outlet 29 is provided with the vertical blade | wing 81 which adjusts the wind direction of the left-right direction with the air direction adjustment mechanism 80 which is also an air outlet opening / closing mechanism. The vertical blades 81 are driven by driving means (not shown) such as a stepping motor that constitutes the wind direction adjusting mechanism 80. Further, at the air outlet 29, a horizontal blade 82 is provided in a direction orthogonal to the vertical blade 81 in order to adjust the wind direction in the vertical direction. The horizontal blade 82 is configured to be manually operated in the air conditioning indoor unit 20. However, the horizontal blade 82 can also be configured to be driven by the wind direction adjusting mechanism 80.

  Unlike the blade 71 of the air inlet 28, the vertical blade 81 of the air outlet 29 stops in a state of being perpendicular to the front surface 51 of the air conditioning indoor unit 20 so that the air outlet 29 does not close when the operation is stopped. It is controlled by the wind direction adjusting mechanism 80.

(3-5) Fan Outlet In this embodiment, as shown in FIG. 5, the indoor fan 22 is disposed in the lower region of the casing 50, and the indoor heat exchanger 21 is disposed in the upper region of the casing 50. It is installed. A fan outlet opening / closing mechanism 91 is provided at the fan outlet 90 of the indoor fan 22, which is an opening that communicates the upper area and the lower area.
As shown in FIGS. 5 and 8, the fan air outlet opening / closing mechanism 91 includes a rectangular closing plate 92 having a size capable of closing the fan air outlet 90, and a circuit provided on one side edge of the closing plate 92. A moving shaft 93 and a motor 94 are provided. The motor 94 has a rotating shaft 94 a, and the tip of the rotating shaft 94 a is connected to one end of the rotating shaft 93. The other end of the rotation shaft 93 is rotatably inserted into a recess 96 formed in a partition plate 95 that partitions the lower region and the upper region of the casing 50. By controlling the driving of the motor 94 by the indoor control device 61 and rotating the motor 94 forward or backward, the closing plate 92 is placed between the state where the fan air outlet 90 is closed and the state where the fan air outlet 90 is opened. Can be rotated.

(4) Control of Suction Port Opening / Closing Mechanism, Wind Direction Adjusting Mechanism, and Fan Blower Outlet Opening / Closing Mechanism Control of the suction port opening / closing mechanism 70, the air direction adjusting mechanism 80, and the fan outlet opening / closing mechanism 91 will be described with reference to the flowchart of FIG. First, the user inputs to the air conditioner indoor unit 20 using the operation panel 65 to turn on the power to the indoor control device 61 (step ST1). At this time, the inlet port 28 is closed by the blade 71, the fan outlet 90 is closed by the closing plate 92, and the outlet 29 is opened. Next, since the operation start time may be delayed later by a timer or the like after the power is turned on, the indoor control device 61 determines whether or not the operation is started (step ST2).

  When the indoor control device 61 determines that the operation is started, the indoor control device 61 transmits an instruction to open the suction port 28 to the suction port opening / closing mechanism 70 and rotates the closing plate 92 with respect to the fan outlet opening / closing mechanism 91. Then, an instruction to open the fan outlet 90 is transmitted, and an instruction to adjust the wind direction of the outlet 29 is transmitted to the wind direction adjusting mechanism 80 (step ST3). The control device 61 maintains the state before the operation is started with respect to the inlet opening / closing mechanism 70, the wind direction adjusting mechanism 80, and the fan outlet opening / closing mechanism 91 until it is determined that the operation is started (step ST2).

  After starting the operation, the indoor control device 61 monitors whether the operation is continued or stopped (step ST4). When the operation is stopped, an instruction to close the suction port 28 is transmitted to the suction port opening / closing mechanism 70 and the fan discharge port 90 is closed by rotating the closing plate 92 to the fan outlet opening / closing mechanism 91. An instruction is transmitted, and an instruction to open the air outlet 29 is transmitted to the wind direction adjusting mechanism 80 (step ST5). After the air inlet opening / closing mechanism 70 closes the air inlet 28, the fan air outlet opening / closing mechanism 91 closes the fan air outlet 90, and the wind direction adjusting mechanism 80 opens the air outlet 29, the process returns to step ST2 and the next operation starts. The indoor control device 61 is monitoring when this is done.

  On the other hand, when it is determined in step ST4 that the operation is continued, the indoor control device 61 confirms whether or not there is an input for turning off the power from the operation panel 65 (step ST6). When there is no input for turning off the power, the process returns to step ST4 to confirm whether or not the operation is stopped again. The indoor control device 61 repeats steps ST4 and ST5 to monitor that there is no instruction to stop the operation and that there is no input for turning off the power.

  When there is an input to turn off the power, the indoor control device 61 does not immediately turn off the power, but the indoor control device 61 causes the suction port opening / closing mechanism 70 to close the suction port 28 and to the fan outlet opening / closing mechanism 91. Then, the fan air outlet 90 is closed and the air outlet 29 is opened to the air direction adjusting mechanism 80 (step ST7), and then the power is turned off (step ST8).

Second Embodiment
(5) Detailed configuration The air conditioning indoor unit 20 according to the first embodiment is configured to open the air outlet 29 when operation is stopped. However, the size and usage state of the indoor RS, the amount of R32 refrigerant used, and the communication piping Depending on the length or the like, it may be better to confine the leaked R32 refrigerant in the air-conditioned indoor unit 20 as much as possible.

  In order to deal with such a case, the air conditioning indoor unit 20 according to the second embodiment is configured to close the air outlet 29 using the vertical blades 81 of the air outlet 29 when the operation is stopped. Therefore, in the air-conditioned room unit 20 according to the second embodiment, the vertical blade 81 is stopped in a state of being parallel to the front surface 51 of the air-conditioned room unit 20 in order to close the outlet 29 when the operation is stopped. It is controlled by the wind direction adjusting mechanism 80. Further, like the plurality of blades 71, when the air outlet 29 of the casing 50 is closed, the plurality of vertical blades 81 are configured to overlap each other.

  Thus, the air-conditioned indoor unit 20 according to the second embodiment is different from the air-conditioned indoor unit 20 of the first embodiment in the control by the indoor control device 61. Therefore, the control of the inlet opening / closing mechanism 70, the airflow direction adjusting mechanism 80, and the fan outlet opening / closing mechanism 91 of the air conditioning indoor unit 20 according to the second embodiment will be described with reference to the flowchart shown in FIG. The control of the indoor control device 61 of the air conditioning indoor unit 20 according to the second embodiment shown in FIG. 10 is performed only by the control by the indoor control device 61 of the first embodiment shown in FIG. 9 and the control of steps ST15 and ST17. Is different. That is, in step ST5 and ST7, the instruction | indication for opening the blower outlet 29 was transmitted with respect to the wind direction adjustment mechanism 80, but the indoor control apparatus 61 which concerns on 2nd Embodiment is in the suction inlet opening / closing mechanism 70. In response, an instruction to close the suction port 28 is transmitted, and an instruction to close the air outlet 29 is also transmitted to the wind direction adjusting mechanism 80 (steps ST15 and ST17). Further, for example, in order to cope with a large amount of refrigerant leakage, a configuration in which a plurality of leakage holes are provided above the outlet may be employed. By adopting such a configuration, the diffusion effect can be further enhanced as compared with the case of overflowing from the air outlet.

(6) Features (6-1)
As described above, the floor-type air-conditioning indoor unit 20 that uses the R32 refrigerant, which is a combustible refrigerant having a specific gravity greater than that of air, has a casing 50 (an example of a casing) that has a lower inlet port 28 for sucking in indoor air. And at least a part of the suction port 28 is disposed at a position lower than the height position of 500 mm from the floor surface FF. Specifically, the height h2 of the opening lower end portion 28a of the suction port 28 from the floor surface FF is set to be less than 500 mm, and the height h2 is about 100 mm in the above embodiment. Then, the suction port opening / closing mechanism 80 opens the suction port 28 when the operation is continued (step ST3), and closes the suction port when the operation is stopped (steps ST5, ST7, ST15, ST17).

  Since the R32 refrigerant is heavier than air, even if the R32 refrigerant leaks in the casing 50 of the air intake indoor unit 20 with the lower suction and upper blowout, the R32 refrigerant is confined in the casing 50 if the amount of the leaked R32 refrigerant is small. Can do. Since there is usually no ignition source in the casing 50 of the air conditioning indoor unit 20, even if the leaked R32 refrigerant fills the casing 50, the risk of fire is kept low. As a result, when the operation of the air conditioning indoor unit 20 is stopped, it is possible to reduce the risk of a fire accident due to the leakage of the R32 refrigerant without detecting the leakage of the R32 refrigerant.

(6-2)
The casing 50 has the blower outlet 29 which blows out conditioned air in room | chamber RS in the upper part, and the opening lower end part 29a (example of a lower end) of the blower outlet 29 is located in the height of 1500 mm or more from a floor surface. Specifically, the height h4 from the floor surface FF of the opening lower end portion 29a of the air outlet 29 of the air conditioning indoor unit 20 is about 1550 mm. With such a configuration, even when the amount of R32 refrigerant leaking is large, the R32 refrigerant can be leaked from the casing 50 to the room RS from the outlet 29 of the casing 50, that is, from a relatively high place. When the leaked R32 refrigerant fills the inside of the air conditioning indoor unit 20 and the R32 refrigerant overflows into the room RS from the air outlet 29, it flows down from the air outlet 29 toward the floor FF. Since it flows down from the height of 1550 mm where 29a is located, the diffusion effect of the R32 refrigerant is enhanced. As a result, the R32 refrigerant hardly reaches the flammable concentration on the floor surface FF, and the risk of fire accidents can be reduced when the R32 refrigerant leaks in the air conditioning indoor unit 20.

(6-3)
The casing 50 of the air conditioning indoor unit 20 according to the first embodiment is configured so that the air outlet 29 does not close when the operation is stopped (steps ST5 and ST7). When the operation is stopped, the air outlet 29 is opened, and the leaked R32 refrigerant filled in the casing 50 can be actively overflowed from the lower opening 29a of the air outlet 29 located at a height of 1500 mm or more. it can. In this way, it is possible to suppress reaching the flammable concentration by using the diffusion effect of the R32 refrigerant flowing down from above.

(6-4)
The air conditioning indoor unit 20 according to the second embodiment includes a wind direction adjusting mechanism 80 (an example of the air outlet opening / closing mechanism) that opens and closes the air outlet 29 of the casing 50. The wind direction adjusting mechanism 80 opens the air outlet 29 when the operation is continued (step ST3), and closes the air outlet 29 when the operation is stopped (steps ST15 and ST17). Thus, since the large opening of the casing 50 can be eliminated by closing the suction port 28 and the air outlet 29 when the operation is stopped, for example, if the refrigerant leakage is very small, the R32 refrigerant leaking during the operation stop is contained in the casing 50. Can be diffused into the room RS after the operation is started. For example, in the case of dealing with a large amount of refrigerant leakage, if a plurality of leakage holes are provided above the outlet 29, it overflows from the outlet 29. The diffusion effect can be further enhanced as compared with the case of making them. As a result, the entire casing 50 can be used to store the leaked R32 refrigerant, and the risk reduction effect of a fire accident due to the leakage of the R32 refrigerant can be easily improved.

(6-5)
The suction port opening / closing mechanism 70 includes a plurality of blades 71 (an example of an opening / closing member), and closes the suction port 28 of the casing 50 by stacking the plurality of blades 71 when the operation is stopped. Thus, by closing the suction port 28 with a plurality of blades 71 stacked on top of each other, the gap when the suction port 28 is closed can be reduced, and the amount of leakage refrigerant leaking from the suction port 28 can be reduced. It is possible to suppress the leaked R32 refrigerant from reaching the flammable concentration in the room RS. As a result, it is possible to further reduce the risk of fire due to the flammable refrigerant.

(6-6)
The fan outlet 90 is closed when the operation is stopped by a fan outlet opening / closing mechanism 91 that opens and closes the fan outlet 90 of the indoor fan 22m. As a result, even if the refrigerant leaks from the indoor heat exchanger 21, it prevents the leaked refrigerant from reaching the lower region of the casing 50 through the fan outlet 90 and further leaking into the room through the air inlet 28 or the like. can do. By closing the suction port 28 when the operation is stopped, leakage of the refrigerant from the lower region of the casing 50 to the room can be substantially prevented. However, by further closing the fan outlet 90, the indoor heat exchanger 21 can be more reliably secured. It is possible to prevent the refrigerant leaking from the leaking into the room.

(6-7)
The fan air outlet opening / closing mechanism 91 includes a rectangular closing plate 92 that can close the fan air outlet 90, a rotating shaft 93 provided on one side edge of the closing plate 92, and a rotating shaft 94a. A motor 94 having a tip of the rotating shaft 94 a connected to one end of the rotating shaft 93 is provided. With a simple configuration in which the closing plate 92 is driven by the motor 94, the fan outlet 90 can be opened and closed.

(7) Modification (7-1) Modification A
In each of the above embodiments, an example in which one air-conditioned room unit 20 is connected to the air-conditioning room outside unit 30 has been described, but a plurality of air-conditioned room units 20 may be connected.

(7-2) Modification B
In each of the above-described embodiments, the case where the suction port 28 and the air outlet 29 are provided only on the front surface 51 of the casing 50 has been described, but the air inlet 28 and / or the air outlet 29 are provided on the right side surface 52 and / or the left side surface 53. May be provided.

(7-3) Modification C
In each of the above embodiments, the fan air outlet 90 is opened and closed by rotating the closing plate 92 with the motor 94. However, instead of the closing plate 92, a lightweight sheet material having a size capable of closing the fan air outlet 90 is used. When the indoor fan 22 is not in operation, the sheet material is urged by a biasing means such as a spring in a direction to close the fan air outlet 90, and when the indoor fan 22 is in operation, the sheet material is erected by the wind pressure. A fan outlet opening / closing mechanism 91 configured to open 90 may be used.

DESCRIPTION OF SYMBOLS 10 Air conditioning apparatus 20 Air-conditioning indoor unit 28 Suction inlet 29 Outlet 50 Casing (housing | casing)
70 suction opening / closing mechanism 71 blade (opening / closing member)
80 Wind direction adjusting mechanism (air outlet opening / closing mechanism)
90 Fan outlet 91 Fan outlet opening and closing mechanism 92 Closure plate

Claims (4)

A floor-type air-conditioning indoor unit that uses a flammable refrigerant having a specific gravity greater than that of air,
A housing (50) having a suction port (28) for sucking room air in the lower part, wherein at least a part of the suction port is disposed at a position lower than a height position of 500 mm from the floor surface;
A suction opening and closing mechanism (70) for opening and closing the suction opening of the housing;
With
The suction port opening / closing mechanism (70) opens the suction port (28) when the operation is continued , and closes the suction port (28) when the operation is stopped .
The casing (50) has an air outlet (29) for blowing conditioned air into the room at the top, and the lower end of the air outlet (29) is located at a height of 1500 mm or more from the floor surface,
The housing (50), that is configured such that the air outlet during operation stop (29) is not close, floor standing type air conditioner indoor unit. The suction opening / closing mechanism ( 70 ) has a plurality of opening / closing members (71), and the plurality of opening / closing members (71) are overlapped with each other when the operation is stopped, and the suction opening (28) of the housing (50). The floor-standing air-conditioning indoor unit according to claim 1, which is closed. A floor-type air-conditioning indoor unit that uses a flammable refrigerant having a specific gravity greater than that of air,
A housing (50) having a suction port (28) for sucking room air in the lower part, wherein at least a part of the suction port is disposed at a position lower than a height position of 500 mm from the floor surface;
A suction opening and closing mechanism (70) for opening and closing the suction opening of the housing;
A fan outlet opening / closing mechanism (91) for opening and closing a fan outlet (90) of an indoor fan (22) disposed in a lower region in the housing (50);
With
The suction port opening / closing mechanism (70) opens the suction port (28) when the operation is continued, and closes the suction port (28) when the operation is stopped.
The fan air outlet opening / closing mechanism (91) is a floor-standing type air-conditioning indoor unit that opens the fan air outlet (90) when the operation is continued and closes the fan air outlet (90) when the operation is stopped . The fan outlet opening / closing mechanism (91) includes a rectangular closing plate (92) capable of closing the fan outlet (90), and a rotation shaft (93) provided on one side edge of the closing plate (92). a) has an axis of rotation (94a), the tip of the rotating shaft (94a) is provided with a motor (94) connected to one end of the pivot shaft (93), in claim 3 The floor-type air conditioning indoor unit as described.