JP6431339B2 - Indoor unit and air conditioner including the same - Google Patents

Description

  The present invention relates to an indoor unit using a combustible refrigerant and an air conditioner including the indoor unit.

  The energy depletion problem and global warming problem in recent years have been attracting attention, and a refrigerant having a high COP (Coefficient of Performance) and a smaller environmental load is also desired for refrigerants used in refrigeration cycles and refrigerators. In particular, there is a high degree of attention to the global warming problem, and there is a demand for a refrigerant that has a low direct impact, i.e., GWP (Global Warming Potential), and low indirect influence, i.e., low energy consumption.

  On the other hand, it may be used near the human body, and safety considerations such as non-toxicity and low flammability are important. Considering the above, the development and selection of refrigerants used in the refrigeration cycle will be performed, and securing volume capacity, COP value, safety, etc. in the system are important selection items. However, there is no excellent refrigerant in all, and it is effective means to give priority to non-toxicity and high performance, and to allow a little flammability conditionally. Here, the condition is to have a means for appropriately detecting when a refrigerant leaks, notifying the user, and taking a safe countermeasure.

  And in the air conditioner of patent document 1, in order to raise the detection accuracy of a leak, the sensor for detecting a combustible refrigerant | coolant is arrange | positioned in the lower part of an indoor unit using the fact that a refrigerant | coolant is heavier than air.

Japanese Patent No. 4599699

  However, if the position of the sensor for detecting leakage is fixed as in Patent Document 1, detection may be delayed or may not be detected depending on the location of the leakage. On the other hand, if erroneous detection by the sensor frequently occurs, a heavy burden is imposed on the user, and it is desirable to eliminate the erroneous detection.

  Therefore, an object of the present invention is to provide an indoor unit capable of suppressing erroneous detection and reliably detecting a leaked refrigerant regardless of the location and amount of leakage of the refrigerant, and an air conditioner including the indoor unit.

  In order to solve the above problems, an indoor unit that is one embodiment of the present invention includes a housing having a blow-in port through which air flows, a blow-out port through which air is blown out, and a louver that changes the direction of the blown-out air, In an indoor unit that forms a refrigeration cycle with a combustible refrigerant with an outdoor unit, a controller that performs a short circuit operation by moving the louver so that air that has exited from the air outlet is directed toward the air inlet A refrigerant sensor that can detect the leaked refrigerant and is installed on the air path in the short circuit operation.

  An air conditioner according to one embodiment of the present invention includes a housing including an outdoor unit, a blow-in port through which air flows, a blow-out port through which air is blown, and a louver that changes the direction of the blown air. In an air conditioner comprising an indoor unit that forms a refrigeration cycle with a combustible refrigerant with the outdoor unit, the louver is moved so that the air that has exited from the outlet is directed to the inlet, The indoor unit further includes a control unit that performs short circuit operation, the indoor unit being capable of detecting the leaked refrigerant, and including a refrigerant sensor installed on the air path in the short circuit operation.

  INDUSTRIAL APPLICABILITY The present invention can provide an indoor unit that can prevent erroneous detection and reliably detect a leaked refrigerant regardless of the location and amount of leakage of the refrigerant, and an air conditioner including the indoor unit.

The block diagram of the multi type air conditioner which concerns on the 1st Embodiment of this invention is shown. The external appearance perspective view of an indoor unit is shown. The refrigerant | coolant detection process flowchart performed in an indoor unit is shown. The schematic of the internal structure of the indoor unit which concerns on the 2nd Embodiment of this invention is shown. It is a figure which shows the state which installed the indoor unit which concerns on the 3rd Embodiment of this invention in the room.

  Hereinafter, an air conditioner including an indoor unit according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a configuration diagram of a multi-type air conditioner 1.

  As shown in FIG. 1, the air conditioner 1 mainly includes one outdoor unit 2, a plurality of indoor units 3, and a remote controller 4. Although three indoor units are shown in FIG. 1, the number of indoor units may be more or less than three.

  The outdoor unit 2 and the indoor unit 3 are connected via a pipe (not shown) and configured to circulate the refrigerant. Examples of the refrigerant used in the present embodiment include a flammable refrigerant having a specific gravity heavier than air, for example, a single refrigerant such as R32 refrigerant, R1234yf, or propane gas, and a flammable mixed refrigerant having these as components.

  The outdoor unit 2 includes an unillustrated outdoor fan, a compressor, a refrigeration cycle component, a temperature / pressure sensor, a blower (not illustrated), a compressor, and the like based on the operating state of the indoor unit 3 and the operating conditions of the remote controller 4. And a control unit 2A for controlling. The outdoor unit 2 is controlled based on a control program stored in the control unit 2A.

  Each indoor unit 3 includes an indoor fan (not shown), a refrigeration cycle component, a temperature / humidity sensor, a control unit 5 that controls the blower and refrigeration cycle component (not shown) based on an operation command from the remote controller 4, and leakage. And a refrigerant sensor 6 for detecting the refrigerant.

  Each remote controller 4 includes a display unit, and gives an operation command to the corresponding indoor unit 3 such as switching between cooling and heating operation, temperature, and air volume setting.

  FIG. 2 shows a perspective view of the indoor unit 3.

  The indoor unit 3 includes a housing 7 having an air inlet 7a and an air outlet 7b. The air outlet 7b is provided with a refrigerant sensor 6 and a louver 8 that changes the direction of the air that is blown out. Moreover, it is desirable that the interior of the indoor unit 3 has an explosion-proof specification with no electrical contact. The refrigerant sensor 6 is provided on the air path in the short circuit operation described later.

  Next, the refrigerant | coolant detection process performed in the indoor unit 3 is demonstrated with reference to FIG. FIG. 3 shows a flowchart of the refrigerant detection process. This process is executed when electricity is supplied to the indoor unit 3. That is, the refrigerant detection process is executed even when the air conditioner 1 is not in a heating or cooling operation. 3 is stored in the ROM of the control unit 5, read out by the microcomputer of the control unit 5, and executed by the CPU.

  First, the control unit 5 determines whether or not the value detected by the refrigerant sensor 6 is equal to or greater than a first threshold (S1). Here, the first threshold value is set to a considerably small value (high sensitivity) so that a small amount of refrigerant leakage can be detected. When the value detected by the refrigerant sensor 6 is equal to or greater than the first threshold (S1: YES), the control unit 5 stops the heating or cooling operation or operates the stopped indoor unit 3. Then, short circuit operation with only air blowing is started (S2). The short circuit operation is an operation in which the louver 8 is moved so that the air exiting from the air outlet 7b is directed to the air inlet 7a as in the air flow F of FIG. It is. Thereby, since the flow F of air circulates through the same path | route, when the refrigerant | coolant has leaked, the density | concentration of a refrigerant | coolant can be raised. If the value detected by the refrigerant sensor 6 is smaller than the first threshold (S1: NO), the process of step S1 is repeated.

  The controller 5 determines whether or not a predetermined time has elapsed since the short circuit operation was started (S3). Here, the predetermined time is a time for increasing the refrigerant concentration in the air flow F. If the predetermined time has not elapsed (S3: NO), the controller 5 repeats the process of step S3. When the predetermined time has elapsed (S3: YES), the control unit 5 determines whether or not the value detected by the refrigerant sensor 6 is equal to or greater than the second threshold (S4). Here, the second threshold value is smaller than the concentration of the refrigerant in the combustion region and higher than the first threshold value.

  When the value detected by the refrigerant sensor 6 is equal to or greater than the second threshold (S4: YES), the control unit 5 notifies the user that the refrigerant has leaked (S5). For example, a sound notifying that the refrigerant has leaked may be output, or a message indicating that the refrigerant has leaked may be displayed on the display unit of the remote controller 4.

  On the other hand, when the value detected by the refrigerant sensor 6 is smaller than the second threshold (S4: NO), the control unit 5 stops the short circuit operation and returns to the original heating or cooling operation or the stop state ( S6). That is, when the leak detection in step S1 is a false detection, the state before the short circuit operation is restored. In addition, you may display on the display part of the remote controller 4 that the trace amount leaking refrigerant | coolant was detected.

  As described above, the indoor unit 3 of the air conditioner 1 according to this embodiment includes the control unit 5 that performs the short circuit operation by moving the louver 8 so that the air that has exited from the air outlet 7b is directed toward the air inlet 7a. The leaked refrigerant can be detected, and is provided with a refrigerant sensor 6 installed on the air passage in short circuit operation.

  With this configuration, when the refrigerant has leaked, the concentration of the leaked refrigerant can be increased by short circuit operation. Thereby, even if it does not make the leak detection of the refrigerant | coolant by the refrigerant | coolant sensor 6 highly sensitive, the detection precision of a refrigerant | coolant leak can be improved and a misdetection can be suppressed. Since the short circuit operation is performed and the refrigerant sensor 6 is installed on the air path of the short circuit operation, the leaked refrigerant can be reliably detected regardless of the location and amount of the leaked refrigerant. Further, by performing the short circuit operation, it is possible to prevent the leaked refrigerant from being diffused into the room.

  The controller 5 starts the short circuit operation when the refrigerant leak is detected by the refrigerant sensor 6 or more than the first threshold value. After the short circuit operation starts, the control unit 5 starts the short circuit operation from the first threshold value. It is determined whether or not there is a refrigerant leakage equal to or higher than the second threshold value. By setting the first threshold value to a highly sensitive value and the second threshold value to a value sufficiently larger than the first threshold value, false detection can be suppressed and refrigerant leakage is reliably detected. can do.

  Moreover, since the refrigerant | coolant sensor 6 is installed in the blower outlet 7b which is on the wind path from the blower inlet 7a to the blower outlet 7b, it can detect the leak of a refrigerant | coolant at an early stage. Further, by installing the refrigerant sensor 6 at the outlet 7b, when the refrigerant sensor 6 is exhausted, it can be easily replaced with a new refrigerant sensor, and maintenance is facilitated.

  Next, an indoor unit 3 according to a second embodiment of the present invention will be described with reference to FIG. In addition, about the same member as 1st Embodiment, the same reference number is attached | subjected and description is abbreviate | omitted and only a different part is demonstrated. FIG. 4 is a schematic diagram of the internal structure of the indoor unit 3 according to the second embodiment.

  The indoor unit 3 in this embodiment differs from the indoor unit in the first embodiment in the position of the refrigerant sensor 6. Specifically, the refrigerant sensor 6 is provided between the indoor heat exchanger 9 and the fan 10. The indoor heat exchanger 9 exchanges heat between the air and the refrigerant, and the fan 10 takes in the outside air E for heat exchange into the housing 7, and the air A after the heat exchange is discharged from the outlet 7b. It blows out of the housing 7.

  The indoor heat exchanger 9 is configured by connecting a plurality of pipes to each other, and has a plurality of connecting portions. And since each connection part is a thin part, it is easy to generate | occur | produce the leakage of a refrigerant | coolant. In the present embodiment, since the refrigerant sensor 6 is disposed between the indoor heat exchanger 9 and the fan 10, leakage of the refrigerant can be detected at an early stage. Note that the indoor unit 3 of the present embodiment also has the same effects as the indoor unit 3 of the first embodiment.

  Next, an indoor unit 3 according to a third embodiment of the present invention will be described with reference to FIG. In addition, about the same member as 1st Embodiment, the same reference number is attached | subjected and description is abbreviate | omitted and only a different part is demonstrated. FIG. 5 is a diagram illustrating a state where the indoor unit 3 according to the third embodiment is installed in the room R.

  As shown in FIG. 5, the indoor unit 3 includes an external refrigerant sensor 11 and a receiving unit 13. The external refrigerant sensor 11 has a transmitter 12 and is installed in the vicinity of the floor outside the housing 7 and below the housing 7. The receiving unit 13 is provided in the housing 7 and can receive information from the transmitting unit 12 of the external refrigerant sensor 11.

  Also in the indoor unit 3 of the present embodiment, the refrigerant detection process described in the first embodiment is executed. However, in this embodiment, the process of step S1 is performed based on the value detected by the external refrigerant sensor 11. That is, the value detected by the external refrigerant sensor 11 is transmitted by the transmission unit 12 to the reception unit 13, and the control unit 5 determines whether or not the value detected by the refrigerant sensor 11 is equal to or greater than the first threshold value. To do.

  When a refrigerant having a higher specific gravity than air is used, the leaked refrigerant tends to accumulate near the floor surface. In the indoor unit 3 of the present embodiment, since the external refrigerant sensor 11 is installed on the lower side of the casing 7 and in the vicinity of the floor surface, the refrigerant leaks outside the casing 7 or when the indoor unit 3 is stopped. When this occurs, the leaked refrigerant can be detected at an early stage. Note that leakage refrigerant detection after the short circuit operation is performed by the refrigerant sensor 6 as in the first embodiment.

  In addition, this invention is not limited to the Example mentioned above. A person skilled in the art can make various additions and changes within the scope of the present invention.

  In said embodiment, the process of step S1 and S4 performed judgment by the control part 5 based on the value detected by the refrigerant | coolant sensor 6 (external refrigerant | coolant sensor 11). However, the first threshold value and the second threshold value may be set in the refrigerant sensor 6, the determination may be performed in the refrigerant sensor 6, and the determination result may be transmitted to the control unit 5. In this case, it may be determined by setting the first threshold value and the second threshold value for the refrigerant sensor 6, or two refrigerant sensors are provided, and the first threshold value is set for one refrigerant sensor, A second threshold value may be set for the other refrigerant sensor, and each refrigerant sensor may make a determination.

  In the third embodiment, the process of step S1 is executed based on the value detected by the external refrigerant sensor 11, but may be executed based on the value detected by both the external refrigerant sensor 11 and the refrigerant sensor 6. .

  If a negative determination is made in step S4 (S4: NO), the number of times may be stored. If the number of negative determinations exceeds the predetermined number in the predetermined period, the refrigerant sensor 6 is exhausted, so that a message indicating that replacement is necessary is displayed on the display unit or the like of the remote controller 4. Also good. Since the refrigerant sensor 6 is generally easily consumed, such a configuration can facilitate replacement of the refrigerant sensor 6 and suppress erroneous detection by the refrigerant sensor 6.

  Further, the refrigerant detection process may be performed not by the control unit 5 of the indoor unit 3 but by the control unit 2A of the outdoor unit 2.

1: air conditioner, 2: outdoor unit, 2A: control unit, 3: indoor unit, 5: control unit, 6: refrigerant sensor, 7: housing, 7a: air inlet, 7b: air outlet, 8: louver 9: Indoor heat exchanger, 10: Fan, 11: External refrigerant sensor, 12: Transmitter, 13: Receiver

Claims (7)

An indoor unit that includes a housing having a blow-in port through which air flows, a blow-out port through which air is blown, and a louver that changes the direction of the blown air, and forms a refrigeration cycle with a combustible refrigerant with the outdoor unit In
A controller that performs a short circuit operation by moving the louver so that the air exiting from the air outlet is directed to the air inlet;
A refrigerant sensor capable of detecting the leaked refrigerant and installed on an air passage in the short circuit operation ;
The controller starts the short circuit operation when the refrigerant sensor detects a leakage of the refrigerant that is equal to or greater than a first threshold.
The short-circuit after start, by the coolant sensor, an indoor unit you determine whether there is leakage of the first second threshold value or more of the refrigerant is higher than the threshold value. An indoor unit that includes a housing having a blow-in port through which air flows, a blow-out port through which air is blown, and a louver that changes the direction of the blown air, and forms a refrigeration cycle with a combustible refrigerant with the outdoor unit In
A controller that performs a short circuit operation by moving the louver so that the air exiting from the air outlet is directed to the air inlet;
The refrigerant that has been leaked can be detected, and a refrigerant sensor installed on the air path in the short circuit operation;
An external refrigerant sensor that has a transmitter and is installed outside the housing and below the housing;
A receiving unit provided in the housing and capable of receiving information from the transmitting unit of the external refrigerant sensor;
The control unit starts the short circuit operation when it is determined by the external refrigerant sensor that leakage of the refrigerant equal to or greater than a first threshold is detected based on information from the transmission unit received by the reception unit. And
2. The indoor unit according to claim 1, wherein after the short circuit operation starts, the refrigerant sensor determines whether or not there is leakage of the refrigerant equal to or higher than a second threshold value that is higher than the first threshold value. The indoor unit according to claim 1 or 2 , wherein the refrigerant sensor is installed on an air path from the inlet to the outlet. An indoor heat exchanger and an indoor fan;
The indoor unit according to claim 3 , wherein the refrigerant sensor is installed between the indoor heat exchanger and the indoor fan. The indoor unit according to claim 3 , wherein the refrigerant sensor is installed at the outlet of the housing. Outdoor unit,
A refrigeration cycle is formed by a combustible refrigerant with the outdoor unit having a housing including a blow-in port through which air flows in, a blow-out port through which air is blown out, and a louver that changes the direction of the blow-out air. In an air conditioner comprising an indoor unit,
The louver is moved so that the air that has exited from the air outlet is directed to the air inlet, and further includes a control unit that performs a short circuit operation,
The indoor unit is capable of detecting the leaked refrigerant, and includes a refrigerant sensor installed on the air path in the short circuit operation ,
The controller starts the short circuit operation when the refrigerant sensor detects a leakage of the refrigerant that is equal to or greater than a first threshold.
After the short-circuit operation start, said by the coolant sensor, an air conditioner you determine whether there is leakage of the first second threshold value or more of the refrigerant is higher than the threshold value. Outdoor unit,
A refrigeration cycle is formed by a combustible refrigerant with the outdoor unit having a housing including a blow-in port through which air flows in, a blow-out port through which air is blown out, and a louver that changes the direction of the blow-out air. In an air conditioner comprising an indoor unit,
A controller that performs a short circuit operation by moving the louver so that the air exiting from the air outlet is directed to the air inlet;
An external refrigerant sensor that has a transmitter and is installed outside the housing and below the housing;
A receiving unit provided in the housing and capable of receiving information from the transmitting unit of the external refrigerant sensor;
The indoor unit is capable of detecting the leaked refrigerant, and includes a refrigerant sensor installed on the air path in the short circuit operation,
The control unit starts the short circuit operation when it is determined by the external refrigerant sensor that leakage of the refrigerant equal to or greater than a first threshold is detected based on information from the transmission unit received by the reception unit. And
An air conditioner that determines whether or not there is a leakage of the refrigerant equal to or higher than a second threshold value that is higher than the first threshold value by the refrigerant sensor after the short circuit operation starts.

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