JP6949217B2 - Indoor unit of air conditioner and air conditioner - Google Patents

Description

The present invention relates to an indoor unit and an air conditioner of an air conditioner including a sensor for detecting a refrigerant leaked from a refrigerant pipe.

Some refrigerants used in air conditioners are flammable. Therefore, in the unlikely event of leakage, if the refrigerant concentration in the indoor space mixed with the refrigerant exceeds a certain lower limit ignition concentration, ignition may occur. Therefore, a technique for detecting the refrigerant leaked from the refrigerant pipe is known (see, for example, Patent Documents 1 and 2).

Patent Document 1 discloses a technique for determining whether or not the refrigerant leaked into the indoor space is agitated. In Patent Document 1, when it is determined that the blower is operating and the refrigerant is agitated, the alarm threshold of the refrigerant leakage sensor is raised to reduce the sensitivity. On the other hand, when it is determined that the blower is stopped and the refrigerant is not agitated, the alarm threshold of the refrigerant leakage sensor is lowered to increase the sensitivity. This promotes the detection of the refrigerant.

Patent Document 2 discloses a technique in which a plurality of refrigerant leakage sensors are installed at outlets in a housing. In Patent Document 2, the alarm threshold is lowered to increase the sensitivity of the sensor when the blower is operating, and the alarm threshold is increased to decrease the sensitivity of the sensor when the blower is stopped.

JP-A-2017-053517 Japanese Unexamined Patent Publication No. 2014-224612

In Patent Document 2, a refrigerant leakage sensor is installed at the outlet, and the sensitivity of the refrigerant leakage sensor during operation of the blower is set higher than that at the time of stopping. On the other hand, in Patent Document 1, the sensitivity of the refrigerant leakage sensor during blower operation is set lower than that at the time of stopping.

Here, when the blower of the indoor unit of the air conditioner is operating, the refrigerant leaked into the housing is agitated. Therefore, it is difficult to detect the refrigerant leakage immediately after the leakage. In view of this situation, it is preferable to lower the alarm threshold value to increase the sensitivity of the sensor during operation of the blower as described in Patent Document 2.

However, in the technique of Patent Document 2, the refrigerant leakage sensor is arranged at the air outlet in the housing of the indoor unit. In this case, the refrigerant leaked in the housing of the indoor unit is agitated during the operation of the blower until it reaches the outlet. First, the agitated refrigerant is mixed with air to reduce the refrigerant concentration, making it difficult to detect refrigerant leakage. Second, if there is no refrigerant leakage sensor in the distribution path where the concentration of the agitated refrigerant is high, it is difficult to detect the refrigerant leakage. In particular, when the distribution route with a high concentration of refrigerant agitated by a ceiling-embedded indoor unit that blows out in all directions is biased, if there is no refrigerant leakage sensor on the distribution route with a high concentration of refrigerant, refrigerant leakage can be detected. It may not be possible.

An object of the present invention is to solve the above problems, and an object of the present invention is to provide an indoor unit and an air conditioner of an air conditioner that can reliably detect refrigerant leakage not only when the blower is stopped but also during operation. ..

The indoor unit of the air conditioner according to the present invention includes a high-sensitivity sensor that detects the refrigerant leaked from the refrigerant pipe and a low-sensitivity sensor that detects the refrigerant leaked from the refrigerant pipe with a lower sensitivity than the high-sensitivity sensor. The high-sensitivity sensor is arranged at an air suction port.

The air conditioner according to the present invention includes the indoor unit of the above air conditioner.

According to the indoor unit and the air conditioner of the air conditioner according to the present invention, the high sensitivity sensor is arranged at the air suction port. Therefore, when the leaked refrigerant mixed with the indoor air as a whole is sucked from the suction port after being blown out from the indoor unit, the refrigerant leak can be detected quickly by the high-sensitivity sensor. Thereby, the refrigerant concentration in the indoor space mixed with the refrigerant can be prevented from exceeding a certain lower limit ignition concentration. Further, since the low-sensitivity sensor is provided separately from the high-sensitivity sensor, refrigerant leakage can be reliably detected even if either of the sensors fails. Therefore, the refrigerant leakage can be reliably detected not only when the blower is stopped but also when it is in operation.

It is a refrigerant circuit diagram which shows the air conditioner which concerns on Embodiment 1 of this invention. It is a lower view which shows the indoor unit of the air conditioner which concerns on Embodiment 1 of this invention in the state which sucked in and removed the grill. It is sectional drawing which shows the indoor unit of the air conditioner which concerns on Embodiment 1 of this invention by the cross section of the X-ray line of FIG. It is explanatory drawing which shows the indoor unit of the air conditioner which concerns on Embodiment 1 of this invention in the state which attached the sensor holder to the electric component box. It is a front view which shows the 1st sensor holder which concerns on Embodiment 1 of this invention. It is a left side view which shows the 1st sensor holder which concerns on Embodiment 1 of this invention. It is a right side view which shows the 1st sensor holder which concerns on Embodiment 1 of this invention. It is an internal development view which shows the 1st sensor holder which concerns on Embodiment 1 of this invention. It is a front view which shows the 2nd sensor holder which concerns on Embodiment 1 of this invention. It is a left side view which shows the 2nd sensor holder which concerns on Embodiment 1 of this invention. It is a right side view which shows the 2nd sensor holder which concerns on Embodiment 1 of this invention. It is a block diagram which shows the electric component box which constituted the determination part which concerns on Embodiment 1 of this invention. It is a figure which shows the detection timing with respect to the leakage refrigerant concentration of the high-sensitivity sensor and low-sensitivity sensor which concerns on Embodiment 1 of this invention. It is a flowchart which shows the routine which detects the refrigerant leakage by the high-sensitivity sensor and low-sensitivity sensor which concerns on Embodiment 1 of this invention. It is explanatory drawing which shows the indoor unit of the air conditioner which concerns on the modification 1 of Embodiment 1 of this invention in the state which attached the sensor holder to the electric component box.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each figure, those having the same reference numerals are the same or equivalent thereof, and they are common in the entire text of the specification. Further, in the cross-sectional view, hatching is omitted as appropriate in view of visibility. Furthermore, the forms of the components shown in the full text of the specification are merely examples and are not limited to these descriptions.

Embodiment 1.
<Structure of air conditioner 100>
FIG. 1 is a refrigerant circuit diagram showing an air conditioner 100 according to a first embodiment of the present invention. In the air conditioner 100 shown in FIG. 1, the outdoor unit 101 and the indoor unit 102 are connected by a gas refrigerant pipe 103 and a liquid refrigerant pipe 104.

The outdoor unit 101 includes a compressor 105, a four-way valve 106, an outdoor heat exchanger 107, an expansion valve 108, and a blower 109.

The compressor 105 compresses and discharges the sucked refrigerant. The compressor 105 may arbitrarily change the operating frequency by, for example, an inverter circuit or the like, and change the capacity for delivering the refrigerant per unit time of the compressor 105.

The four-way valve 106 is a valve that switches the flow of the refrigerant depending on, for example, the cooling operation and the heating operation.

The outdoor heat exchanger 107 exchanges heat between the refrigerant and the outdoor air. The outdoor heat exchanger 107 functions as a condenser during the cooling operation to condense and liquefy the refrigerant. The outdoor heat exchanger 107 functions as an evaporator during the heating operation to evaporate and vaporize the refrigerant.

The expansion valve 108 is a flow rate control valve, and decompresses and expands the refrigerant. When the expansion valve 108 is composed of, for example, an electronic expansion valve, the opening degree can be adjusted based on the instruction of the control unit 110.

The blower 109 blows outside air to the outdoor heat exchanger 107 to promote heat exchange of the outdoor heat exchanger 107.

Further, the outdoor unit 101 includes a control unit 110. The control unit 110 communicates with the determination unit 5 of the indoor unit 102, which will be described later, to perform various controls.

The indoor unit 102 has an indoor heat exchanger 1 and a blower 2.

The indoor heat exchanger 1 exchanges heat between, for example, air to be air-conditioned and a refrigerant. The indoor heat exchanger 1 functions as an evaporator during the cooling operation to evaporate and vaporize the refrigerant. The indoor heat exchanger 1 functions as a condenser during the heating operation to condense and liquefy the refrigerant.

The blower 2 blows indoor air to the indoor heat exchanger 1 to promote heat exchange in the indoor heat exchanger 1.

By configuring the air conditioner 100 as described above, the flow of the refrigerant can be switched by the four-way valve 106 of the outdoor unit 101, and cooling operation or heating operation can be realized.

Further, the indoor unit 102 includes a high-sensitivity sensor 3, a low-sensitivity sensor 4, and a determination unit 5.

The high-sensitivity sensor 3 detects the refrigerant leaked from the refrigerant pipe in the indoor unit 102. The low-sensitivity sensor 4 detects the refrigerant leaked from the refrigerant pipe in the indoor unit 102 with a lower sensitivity than the high-sensitivity sensor 3. Here, the refrigerant pipes are all pipes through which the refrigerant flows, including the gas refrigerant pipe 103, the liquid refrigerant pipe 104, and the heat transfer pipe of the indoor heat exchanger 1.

The determination unit 5 determines the refrigerant leakage based on the detection information of the high-sensitivity sensor 3 and the low-sensitivity sensor 4.

<Structure of indoor unit 102>
FIG. 2 is a bottom view showing the indoor unit 102 of the air conditioner 100 according to the first embodiment of the present invention in a state where the suction grill is removed. FIG. 3 is a cross-sectional view showing the indoor unit 102 of the air conditioner 100 according to the first embodiment of the present invention in a cross section taken along line XX of FIG. FIG. 4 is an explanatory view showing the indoor unit 102 of the air conditioner 100 according to the first embodiment of the present invention in a state where the first and second sensor holders 10 and 11 are attached to the electric component box 9.

As shown in FIGS. 2 to 4, in the indoor unit 102, a suction port 6 is formed in the central portion of the housing 7, and an air outlet 8 for blowing out conditioned air is formed on four sides around the suction port 6. It is a ceiling-embedded indoor unit.

The indoor unit 102 is equipped with an electric component box 9, a first sensor holder 10, a second sensor holder 11, a bell mouth 12, a drain pan 13, an indoor heat exchanger 1, and a blower 2 in a housing 7 from which the suction grill is removed. doing.

A determination unit 5 is configured in the electrical component box 9. The electrical component box 9 is installed facing the suction side air passage connected from the suction port 6 to the back. Two first and second sensor holders 10 and 11 are attached to the surface of the electrical component box 9 facing the suction port 6.

The first sensor holder 10 is attached to the surface of the electrical component box 9 and incorporates the high-sensitivity sensor 3 and the suction temperature sensor 14. As a result, the high-sensitivity sensor 3 is arranged at the suction port 6.

The second sensor holder 11 is arranged in parallel with the first sensor holder 10 in the horizontal direction, is attached to the surface portion of the electrical component box 9, and incorporates the low-sensitivity sensor 4. The second sensor holder 11 does not have a built-in suction temperature sensor. As a result, the low-sensitivity sensor 4 is arranged at the suction port 6.

The positions where the first and second sensor holders 10 and 11 are attached are positions below the indoor heat exchanger 1. As a result, the low-sensitivity sensor 4 is arranged at a position below the indoor heat exchanger 1.

The high-sensitivity sensor 3 and the low-sensitivity sensor 4 output analog output signals. Therefore, when a communication line such as a lead wire connecting the high-sensitivity sensor 3 and the low-sensitivity sensor 4 to the determination unit 5 runs in parallel with the power supply line or the blower 2, there is a concern that noise may be added to the sensor output signal. On the other hand, by installing the first and second sensor holders 10 and 11 directly in the electrical component box 9, the communication line is shortened and the adverse effect of noise is prevented.

When the blower 2 is operated, the leaked refrigerant is diluted by the blower, and it is difficult to detect the refrigerant leak. Therefore, when the refrigerant concentration in the indoor air becomes high within the range below the ignition lower limit concentration, the high-sensitivity sensor 3 and the low-sensitivity sensor 4 are located near the suction port 6 so that the high-sensitivity sensor 3 or the low-sensitivity sensor 4 can detect the refrigerant concentration. Is installed.

<Configuration of high-sensitivity sensor 3>
FIG. 5 is a front view showing the first sensor holder 10 according to the first embodiment of the present invention. FIG. 6 is a left side view showing the first sensor holder 10 according to the first embodiment of the present invention. FIG. 7 is a right side view showing the first sensor holder 10 according to the first embodiment of the present invention. FIG. 8 is an internally developed view showing the first sensor holder 10 according to the first embodiment of the present invention.

As shown in FIGS. 5 to 8, the high-sensitivity sensor 3 is built in the first sensor holder 10 together with the suction temperature sensor 14. The first sensor holder 10 is formed with a plurality of slits 10a so that the suction air directly hits the high-sensitivity sensor 3 and the suction temperature sensor 14. The high-sensitivity sensor 3 is mainly configured by using a sensitive gas element made of a semiconductor, and outputs due to the oxygen concentration.

<Configuration of low-sensitivity sensor 4>
FIG. 9 is a front view showing the second sensor holder 11 according to the first embodiment of the present invention. FIG. 10 is a left side view showing the second sensor holder 11 according to the first embodiment of the present invention. FIG. 11 is a right side view showing the second sensor holder 11 according to the first embodiment of the present invention.

As shown in FIGS. 9 to 11, the low-sensitivity sensor 4 is built in the second sensor holder 11. The second sensor holder 11 is formed with a plurality of slits 11a so that the low-sensitivity sensor 4 is directly exposed to the suction air. The low-sensitivity sensor 4 is mainly configured by using a sensitive gas element made of a semiconductor, and outputs due to the oxygen concentration. The low-sensitivity sensor 4 outputs due to an oxygen concentration lower than that of the high-sensitivity sensor 3 from the beginning of manufacture, and detects the refrigerant with a lower sensitivity than the high-sensitivity sensor 3.

<Structure of judgment unit 5>
FIG. 12 is a block diagram showing an electrical component box 9 constituting the determination unit 5 according to the first embodiment of the present invention. As shown in FIG. 12, the determination unit 5 is a processing circuit including a microcomputer including a memory such as a CPU, ROM and RAM, and an input / output device such as an I / O port. The control unit 110 mounted on the outdoor unit 101 has a processing circuit similar to that of the determination unit 5.

The determination unit 5 constantly or periodically detects the leaked refrigerant by the low-sensitivity sensor 4 regardless of whether the blower 2 is operated or stopped. The determination unit 5 detects the leaked refrigerant with the high-sensitivity sensor 3 during the operation of the blower 2. The determination unit 5 stops the detection of the high-sensitivity sensor 3 when the blower 2 is stopped. When the high-sensitivity sensor 3 or the low-sensitivity sensor 4 detects the leakage of the refrigerant, the determination unit 5 transmits the detection information to the control unit 110 of the outdoor unit 101. As a result, the control unit 110 of the outdoor unit 101 closes the on-off valve or the like in the middle of the refrigerant circuit, and performs protection control such as pumping down to prevent the refrigerant from being supplied to the indoor unit 102.

<Characteristics of high-sensitivity sensor 3 and low-sensitivity sensor 4>
FIG. 13 is a diagram showing the detection timing of the high-sensitivity sensor 3 and the low-sensitivity sensor 4 according to the first embodiment of the present invention with respect to the leakage refrigerant concentration. In FIG. 13, the vertical axis shows the concentration of the leaked refrigerant in the indoor air. The horizontal axis is the time axis. The detection timing basically shows a proportional characteristic that rises to the right.

As shown in FIG. 13, the first detection point of the high-sensitivity sensor 3 is a point when the leakage refrigerant concentration is the first threshold value. The first threshold value is a value at which a false detection is issued by the high-sensitivity sensor 3 due to a decrease in oxygen concentration when the blower 2 is stopped, for example, when the user sprays the pest control agent in the indoor space. .. The first threshold value is the same component as the leaked refrigerant when the blower 2 is stopped, for example, when the user sprays a deodorant spray containing the same component as a refrigerant such as propane onto the indoor space or the indoor unit 102. This is a value at which an erroneous detection by the high-sensitivity sensor 3 due to the detection of the above is issued. As described above, the first threshold value is a value with high sensitivity to the extent that erroneous detection is performed on a daily basis when the blower 2 is stopped.

The second detection point of the low-sensitivity sensor 4 is a point when the leakage refrigerant concentration is a second threshold value having a concentration higher than the first threshold value. The second threshold value is a value at which false detection is not issued by the low-sensitivity sensor 4 due to a decrease in oxygen concentration when the blower 2 is stopped, for example, when the user sprays the pest control agent in the indoor space. The second threshold value is the same component as the leaked refrigerant when the blower 2 is stopped, for example, when the user sprays a deodorant spray containing the same component as a refrigerant such as propane onto the indoor space or the indoor unit 102. This is a value at which false detection by the low-sensitivity sensor 4 due to the detection of is not issued. As described above, the second threshold value is a low-sensitivity value that does not cause false detection in daily life when the blower 2 is stopped. However, in the second threshold value, the leakage refrigerant concentration is lower than the lower limit ignition concentration value. Therefore, the low-sensitivity sensor 4 has a detection timing delayed from that of the high-sensitivity sensor 3 after the refrigerant concentration becomes high, but the refrigerant leaks at a point where the leakage refrigerant concentration in the indoor air is lower than the lower limit ignition concentration value. Can be detected.

<Leaked refrigerant detection operation>
FIG. 14 is a flowchart showing a routine for detecting refrigerant leakage with the high-sensitivity sensor 3 and the low-sensitivity sensor 4 according to the first embodiment of the present invention. This routine is repeated sequentially.

In step S101, the determination unit 5 detects the leaked refrigerant with the low-sensitivity sensor 4. As shown in FIG. 13, the low-sensitivity sensor 4 notifies that the detection is performed when the leakage refrigerant concentration reaching the second detection point is at the second threshold value. After the process of step S101, the process proceeds to step S102.

In step S102, the determination unit 5 determines whether or not the blower 2 is in operation. If the blower 2 is in operation, the process proceeds to step S103. If the blower 2 is stopped, the process proceeds to step S104.

In step S103, the determination unit 5 detects the leaked refrigerant with the high-sensitivity sensor 3. As shown in FIG. 13, the high-sensitivity sensor 3 notifies that the detection is performed when the leakage refrigerant concentration that has reached the first detection point is the first threshold value. When the blower 2 is operating, it detects when the refrigerant leaked into the room is sucked from the suction port 6, so that it is quick to detect the sucked refrigerant with the highly sensitive high-sensitivity sensor 3. be. After the process of step S103, the process proceeds to step S105.

In step S104, the determination unit 5 stops the detection of the high-sensitivity sensor 3. According to this, it is possible to prevent erroneous detection by the high-sensitivity sensor 3 due to a decrease in oxygen concentration when the blower 2 is stopped, for example, when the user sprays the pest control agent in the indoor space. Further, it is caused by the detection of the same component as the leaked refrigerant when the blower 2 is stopped, for example, when the user sprays the indoor space or the indoor unit 102 with a deodorant spray containing the same component as the refrigerant such as propane. False detection by the high-sensitivity sensor 3 can be prevented. Further, even in this case, since the low-sensitivity sensor 4 is in the detection state, it is possible to detect even if the refrigerant leaks from any of the refrigerant pipes in the housing 7. After the process of step S104, the process proceeds to step S105.

In step S105, the determination unit 5 determines whether or not the high-sensitivity sensor 3 or the low-sensitivity sensor 4 has detected the leaked refrigerant. If a refrigerant leak is detected, the process proceeds to step S106. If no refrigerant leakage is detected, this routine is temporarily terminated.

In step S106, the determination unit 5 implements protection control such as pump down. This ensures the safety of the user. After that, this routine is terminated once.

<Modification example 1>
FIG. 15 is an explanatory view showing the indoor unit 102 of the air conditioner 100 according to the first modification of the first embodiment of the present invention in a state where the first and second sensor holders 10 and 11 are attached to the electrical component box 9. be. In the first modification, the same items as those in the above embodiment will be omitted, and only the characteristic portions thereof will be described.

As shown in FIG. 15, the high-sensitivity sensor 3 is arranged on the suction upstream side of the suction port 6 with respect to the low-sensitivity sensor 4. That is, two high-sensitivity sensors 3 and low-sensitivity sensors 4 are installed side by side. In other words, the first and second sensor holders 10 and 11 are installed side by side. As a result, the low-sensitivity sensor 4 is installed at a higher position, and it becomes easier to detect the refrigerant leaked from the indoor heat exchanger 1 when the blower 2 is stopped. The refrigerant leaked from the indoor heat exchanger 1 accumulates in the drain pan 13 and eventually leaks to the primary side where the suction port 6 is located. At that time, the low-sensitivity sensor 4 detects the leaked refrigerant as soon as possible.

<Effect of indoor unit 102>
As described above, the high-sensitivity sensor 3 and the low-sensitivity sensor 4 can reliably detect the refrigerant leakage, the indoor air does not reach the lower limit ignition concentration, and the safe air conditioner 100 can be realized.

<Effect of Embodiment 1>
According to the first embodiment, the indoor unit 102 of the air conditioner 100 includes a high-sensitivity sensor 3 that detects the refrigerant leaked from the refrigerant pipe. The indoor unit 102 of the air conditioner 100 includes a low-sensitivity sensor 4 that detects the refrigerant leaked from the refrigerant pipe with a lower sensitivity than the high-sensitivity sensor 3. The high-sensitivity sensor 3 is arranged at the air suction port 6.

According to this configuration, the refrigerant leaked from the inside of the housing 7 is diluted during the operation of the blower 2, and even if the refrigerant leak sensor installed at the outlet 8 as in Patent Document 2 cannot detect the refrigerant leak instantly, the suction is sucked. Refrigerant leakage can be detected by the high-sensitivity sensor 3 at the port 6. That is, when the leaked refrigerant mixed with the indoor air as a whole is sucked from the suction port 6 after being blown out from the indoor unit 102, the high-sensitivity sensor 3 can quickly detect the leaked refrigerant. Thereby, the refrigerant concentration in the indoor space mixed with the refrigerant can be prevented from exceeding a certain lower limit ignition concentration. For example, if the refrigerant is R32, the concentration can not exceed 14 vol%. Further, the low-sensitivity sensor 4 is provided separately from the high-sensitivity sensor 3. As a result, when the blower 2 is stopped, if a refrigerant having a specific density higher than that of air stays at the bottom of the housing 7, the low-sensitivity sensor 4 can detect the refrigerant leakage. Then, even if either of the sensors 3 and 4 fails, the refrigerant leakage can be reliably detected by the sensors 3 and 4. Therefore, the refrigerant leakage can be reliably detected not only when the blower 2 is stopped but also when it is in operation.

According to the first embodiment, the low-sensitivity sensor 4 is arranged at the air suction port 6.

According to this configuration, when the blower 2 is stopped, if a refrigerant having a specific density higher than that of air stays at the bottom of the housing 7, the low-sensitivity sensor 4 can detect the refrigerant leakage. Further, when the leaked refrigerant mixed with the indoor air as a whole is sucked from the suction port 6 after being blown out from the indoor unit 102, the low-sensitivity sensor 4 can detect the refrigerant leak later than the high-sensitivity sensor 3. Thereby, the refrigerant concentration in the indoor space mixed with the refrigerant can be prevented from exceeding a certain lower limit ignition concentration. For example, if the refrigerant is R32, the concentration can not exceed 14 vol%. Then, even if either of the sensors 3 and 4 fails, the refrigerant leakage can be reliably detected by the sensors 3 and 4. Therefore, the refrigerant leakage can be reliably detected not only when the blower 2 is stopped but also when it is in operation.

According to the first embodiment, the indoor unit 102 of the air conditioner 100 includes a blower 2. The indoor unit 102 of the air conditioner 100 includes a determination unit 5 that determines refrigerant leakage based on the detection information of the high-sensitivity sensor 3 and the low-sensitivity sensor 4. The determination unit 5 detects the leaked refrigerant with the high-sensitivity sensor 3 during the operation of the blower 2.

According to this configuration, when the refrigerant leaked from the housing 7 during the operation of the blower 2 is blown out from the indoor unit 102 and then the leaked refrigerant totally mixed with the indoor air is sucked from the suction port 6, the height is high. Refrigerant leakage can be detected quickly by the sensitivity sensor 3.

According to the first embodiment, the determination unit 5 stops the detection of the high-sensitivity sensor 3 when the blower 2 is stopped.

According to this configuration, it is possible to prevent erroneous detection by the high-sensitivity sensor 3 due to a decrease in oxygen concentration when the blower 2 is stopped, for example, when the user sprays the pest control agent in the indoor space. Further, it is caused by the detection of the same component as the leaked refrigerant when the blower 2 is stopped, for example, when the user sprays the indoor space or the indoor unit 102 with a deodorant spray containing the same component as the refrigerant such as propane. False detection by the high-sensitivity sensor 3 can be prevented.

According to the first embodiment, the determination unit 5 constantly or periodically detects the leaked refrigerant by the low-sensitivity sensor 4 regardless of whether the blower 2 is operated or stopped.

According to this configuration, when the blower 2 is stopped, if a refrigerant having a specific density higher than that of air stays at the bottom of the housing 7, the low-sensitivity sensor 4 can detect the refrigerant leakage. Further, even if the high-sensitivity sensor 3 fails, the low-sensitivity sensor 4 can reliably detect the refrigerant leakage when the refrigerant concentration in the indoor space mixed with the refrigerant does not exceed a certain lower limit ignition concentration during the operation of the blower 2. .. For example, if the refrigerant is R32, the low-sensitivity sensor 4 can reliably detect refrigerant leakage when the concentration does not exceed 14 vol%.

According to the first embodiment, the indoor unit 102 of the air conditioner 100 includes an indoor heat exchanger 1. The low-sensitivity sensor 4 is arranged at a position below the indoor heat exchanger 1.

According to this configuration, when the blower 2 is stopped, if a refrigerant having a specific density higher than that of air stays at the bottom of the housing 7, the low-sensitivity sensor 4 arranged below the indoor heat exchanger 1 leaks the refrigerant. Can be detected.

According to the first embodiment, the determination unit 5 is configured in the electric component box 9. The electrical component box 9 is installed facing the suction side air passage connected from the suction port 6 to the back. A high-sensitivity sensor 3 is attached to the surface of the electrical component box 9.

According to this configuration, the high-sensitivity sensor 3 may output an output signal in analog. Therefore, when a communication line such as a lead wire connecting the high-sensitivity sensor 3 and the determination unit 5 runs in parallel with the power supply line or the blower 2, there is a concern that noise may be added to the output signal of the high-sensitivity sensor 3. On the other hand, a high-sensitivity sensor 3 is attached to the surface of the electrical component box 9, the communication line is shortened, and the adverse effect of noise can be avoided.

According to the first embodiment, the low-sensitivity sensor 4 is attached to the surface of the electrical component box 9 together with the high-sensitivity sensor 3.

According to this configuration, the low-sensitivity sensor 4 may output an output signal in analog. Therefore, when a communication line such as a lead wire connecting the low-sensitivity sensor 4 and the determination unit 5 runs in parallel with the power supply line or the blower 2, there is a concern that noise may be added to the output signal of the low-sensitivity sensor 4. On the other hand, a low-sensitivity sensor 4 is attached to the surface of the electrical component box 9, the communication line is shortened, and the adverse effect of noise can be avoided.

According to the first embodiment, the high-sensitivity sensor 3 is arranged on the suction upstream side of the suction port 6 with respect to the low-sensitivity sensor 4.

According to this configuration, when the leaked refrigerant that is totally mixed with the indoor air after being blown out from the indoor unit 102 is sucked from the suction port 6, the high-sensitivity sensor 3 can quickly detect the refrigerant leak.

According to the first embodiment, in the indoor unit 102 of the air conditioning device 100, the suction port 6 is formed in the central portion of the housing 7, and the air outlet 8 for blowing out the conditioned air is formed around the suction port 6. It is a ceiling-embedded indoor unit.

According to this configuration, when the distribution path having a high concentration of the refrigerant agitated by the ceiling-embedded indoor unit 102 blown out in all directions is biased, the refrigerant of the outlet 8 is placed on the distribution path having a high concentration of the refrigerant. Without the leak sensor, it may not be possible to detect refrigerant leaks. On the other hand, the high-sensitivity sensor 3 is arranged at the suction port 6. Therefore, when the leaked refrigerant mixed with the indoor air as a whole is sucked from the suction port 6 after being blown out from the indoor unit 102, the high-sensitivity sensor 3 can quickly detect the leaked refrigerant.

According to the first embodiment, the air conditioner 100 includes the indoor unit 102 of the air conditioner 100 described above.

According to this configuration, in the air conditioner 100 including the indoor unit 102 of the air conditioner 100, the refrigerant leakage can be reliably detected not only when the blower 2 is stopped but also when the blower 2 is operated.

1 Indoor heat exchanger, 2 Blower, 3 High-sensitivity sensor, 4 Low-sensitivity sensor, 5 Judgment unit, 6 Suction port, 7 Housing, 8 Outlet, 9 Electrical parts box, 10 1st sensor holder, 10a slit, 11 2nd sensor holder, 11a slit, 12 bell mouth, 13 drain pan, 14 suction temperature sensor, 100 air conditioner, 101 outdoor unit, 102 indoor unit, 103 gas refrigerant pipe, 104 liquid refrigerant pipe, 105 compressor, 106 four-way valve , 107 outdoor heat exchanger, 108 expansion valve, 109 blower, 110 control unit.

Claims (11)

A high-sensitivity sensor that detects the refrigerant leaked from the refrigerant pipe,
A low-sensitivity sensor that detects the refrigerant leaked from the refrigerant pipe with a lower sensitivity than the high-sensitivity sensor,
With
The high-sensitivity sensor is an indoor unit of an air conditioner arranged at an air suction port. The indoor unit of the air conditioner according to claim 1, wherein the low-sensitivity sensor is arranged at the air suction port. Blower and
A determination unit that determines refrigerant leakage based on the detection information of the high-sensitivity sensor and the low-sensitivity sensor, and
With
The indoor unit of the air conditioner according to claim 1 or 2, wherein the determination unit detects the refrigerant leaked by the high-sensitivity sensor during the operation of the blower. The indoor unit of the air conditioner according to claim 3, wherein the determination unit stops the detection of the high-sensitivity sensor when the blower is stopped. The indoor unit of the air conditioner according to claim 3 or 4, wherein the determination unit detects the refrigerant leaked by the low-sensitivity sensor regardless of whether the blower is operated or stopped. Equipped with a heat exchanger
The indoor unit of the air conditioner according to any one of claims 1 to 5, wherein the low-sensitivity sensor is arranged at a position lower than the heat exchanger. The determination unit is configured in the electrical component box.
The electric component box is installed facing the suction side air passage connected to the back from the suction port.
The indoor unit of the air conditioner according to any one of claims 3 to 6, wherein the high-sensitivity sensor is attached to the surface portion of the electrical component box. The indoor unit of the air conditioner according to claim 7, wherein the low-sensitivity sensor is attached to the surface of the electrical component box together with the high-sensitivity sensor. The indoor unit of the air conditioner according to any one of claims 1 to 8, wherein the high-sensitivity sensor is arranged on the suction upstream side of the suction port with respect to the low-sensitivity sensor. 6. Indoor unit of air conditioner. An air conditioner including an indoor unit of the air conditioner according to any one of claims 1 to 10.

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