JP2022024290A - Air conditioner - Google Patents

Abstract

To solve a problem of a conventional air conditioner performing risk avoidance operation at detection of a refrigerant that there is a possibility of performing the operation when there is no leakage, which causes maintenance cost and deterioration in convenience.SOLUTION: An air conditioner includes first refrigerant shut-off means, second refrigerant shut-off means, state detecting means for estimating a state of a refrigerant in an indoor unit, and refrigerant detecting means. When the refrigerant detecting means detects the refrigerant, detection of the refrigerant is notified by notifying means, refrigerant recovery operation is performed, and refrigerant leakage detection processing is performed so as to determine presence/absence of the leakage of the refrigerant, and unnecessary maintenance can be dispensed with by performing suitable operation and action. Thereby, it is possible to provide the air conditioner environmentally-friendly, having high safety and reliability, and excellent in convenience.SELECTED DRAWING: Figure 1

Description

The present invention relates to a technique for preventing leakage of a working refrigerant in an air conditioner that performs air conditioning using a refrigeration and heat pump cycle.

In recent years, in addition to the movement to emphasize the operating efficiency of air conditioners from the viewpoint of preventing global warming, the movement to regulate the use of refrigerants with a large global warming coefficient has been accelerated.

As a refrigerant with a small warming coefficient, carbon dioxide, which originally exists in nature, and hydrocarbons such as propane and butane, which are artificially synthesized, have a double bond in the molecular structure and have a double bond in the atmosphere. Hydrofluoroolefins (HFOs), which decompose in a short time, are attracting attention. As HFOs, 2,3,3,3-tetrafluoro-1-propene (R1234yf), 1,3,3,3-tetrafluoro-1-propene (R1234ze), etc. are attracting attention and some of them. Practical use has begun.

However, carbon dioxide has a high operating pressure and is difficult to use as an air conditioner in terms of operating efficiency, and it cannot be said that carbon dioxide has excellent characteristics as a refrigerant.

In addition, since R1234yf and R1234ze have a high boiling point and a large pressure loss, there is a difficulty in operating efficiency when used in a separate air conditioner such as a room air conditioner, and a multi air conditioner for buildings that uses a large amount of refrigerant, etc. Then, there is also a problem in that it has a slight flammability.

On the other hand, hydrocarbons, especially propane, have excellent characteristics as a refrigerant for air conditioners, but because they have high flame properties, if a refrigerant leaks, there is a risk of fire or explosion. It could not be used easily.

Many inventions have been made conventionally as a technique for improving the safety of a separate air conditioner such as a room air conditioner or a packaged air conditioner using a flammable refrigerant.

As one of them, many technologies have been proposed that detect refrigerant leakage and perform some operation to avoid danger.

Alarms that detect flammable gas and warn the user with sound or display are widely used, and the technology itself to equip them is already known.

Further, as a technique for operating the air conditioner itself, as in the case of the separate type air conditioner described in Patent Document 1, a refrigerant recovery operation is performed when the air conditioner is stopped and when a refrigerant leak is detected, and the refrigerant in the refrigerant circuit of the indoor unit is removed. A technique has been proposed to prevent the refrigerant from leaking into the room by collecting the refrigerant in the refrigerant circuit of the outdoor unit and stopping the air conditioner.

Further, Patent Document 2 includes a refrigerant leakage detecting means for detecting a refrigerant and a leaking refrigerant diffusing means for imparting a stirring action to the leaking refrigerant to diffuse it. When a refrigerant leak is detected, the refrigerant is agitated by the leaking refrigerant diffusing means. Diffuse to prevent the formation of flammable areas.

Then, in Patent Document 3, ammonia is used as a refrigerant, and when a refrigerant leak is detected, a damper is operated to perform exhaust ventilation.

In Patent Documents 2 and 3, the air conditioner itself, such as an indoor blower, is used for stirring and ventilation, but there are also examples of stirring and ventilation in cooperation with another ventilation fan or circulator. be.

Further, as in Patent Document 4, a technique has been proposed in which all the refrigerant in the refrigerant circuit is discarded to the outside when a refrigerant leak is detected.

Japanese Unexamined Patent Publication No. 8-166171 Japanese Unexamined Patent Publication No. 11-37619 Japanese Patent No. 3291407 Japanese Patent No. 3775920

In the conventional air conditioners of Patent Document 1, Patent Document 2, and Patent Document 3, when a refrigerant leak is detected, the danger of ignition or explosion in the room can be avoided, but after the danger is avoided. There is no particular mention of the response.

Patent Document 4 cannot be operated without maintenance after the danger avoidance operation.

When the refrigerant leak detection device detects a refrigerant leak, if the working refrigerant is actually leaking, it is necessary to perform maintenance and use the air conditioner. Therefore, maintenance may be performed after the crisis avoidance operation.

However, since the refrigerant leakage detection device also reacts to the gas generated by an external factor other than the working refrigerant, there is a possibility that the danger avoidance operation is performed even though the refrigerant is not leaking. At that time, it is difficult for a general user to judge the necessity of maintenance, and even if there is no problem with the air conditioner, the service must be requested, which causes problems such as cost generation and deterioration of convenience. Occur.

Therefore, the present invention solves these problems, detects a refrigerant leak, performs a danger avoidance operation, automatically determines whether it is an automatic recovery or a maintenance request after the danger avoidance operation, and provides a device having excellent safety and convenience. It is something to do.

In order to solve the above-mentioned conventional problems, the air conditioner of the present invention has a compressor that compresses and sends out the working refrigerant, and outdoor heat that exchanges heat between the outdoor air sent by the outdoor blower and the working refrigerant. An air conditioner that constitutes a refrigeration or heat pump cycle with an outdoor unit having a exchanger and an indoor unit having an indoor heat exchanger that exchanges heat between the indoor air sent by the indoor blower and the working refrigerant. A first refrigerant blocking means for blocking the first refrigerant path connecting the outdoor unit and the indoor unit, and a second refrigerant blocking means for blocking the second refrigerant path connecting the outdoor unit and the indoor unit. The operation of the device, a state detecting means for estimating the state of the working refrigerant of the indoor unit, a refrigerant detecting means for detecting the working refrigerant, a notifying means for notifying that the refrigerant detecting means has detected the working refrigerant, and the operation of the device. The state detecting means includes at least two or more of a refrigerant temperature detecting means, a refrigerant pressure detecting means, a temperature detecting means, and a compressor power detecting means, and the refrigerant detecting means detects an operating refrigerant. If so, the notification means notifies, and the control means closes the second refrigerant blocking means based on the output of the state detecting means, collects the working refrigerant in the outdoor unit, and then determines the presence or absence of refrigerant leakage. If it is determined that there is no refrigerant leakage, the operation returns to the operation before the refrigerant detecting means detects the working refrigerant.

As a result, the leakage of the working refrigerant can be minimized, and even when the refrigerant detecting means outputs the refrigerant detection output, the refrigerant leakage can be determined and appropriate operation and operation can be performed.

The air conditioner of the present invention minimizes the leakage of the working refrigerant, and performs appropriate operation and operation even when the refrigerant detecting means outputs the refrigerant detection output even though the working refrigerant is not leaking. Therefore, it is possible to provide an air conditioner having a small environmental load, high safety and reliability, and high convenience.

Configuration diagram of the air conditioner harmonizer according to the first embodiment of the present invention Flow chart of control related to refrigerant detection of the air conditioner harmonizer according to the first embodiment of the present invention.

In the first aspect of the invention, in order to solve the above-mentioned conventional problems, the air conditioner of the present invention has a compressor that compresses and sends out the working refrigerant, and an outdoor air sent by the outdoor blower between the working refrigerant. A refrigeration or heat pump cycle is composed of an outdoor unit having an outdoor heat exchanger that exchanges heat with the refrigerant and an indoor unit having an indoor heat exchanger that exchanges heat between the indoor air sent by the indoor blower and the working refrigerant. A first refrigerant blocking means for blocking the first refrigerant path connecting the outdoor unit and the indoor unit, and a second refrigerant path connecting the outdoor unit and the indoor unit. 2 Refrigerant shutoff means, a state detecting means for estimating the state of the working refrigerant of the indoor unit, a refrigerant detecting means for detecting the working refrigerant, and a notifying means for notifying that the refrigerant detecting means has detected the working refrigerant. The state detecting means includes at least two or more of a refrigerant temperature detecting means, a refrigerant pressure detecting means, a temperature detecting means, and a compressor power detecting means, and the state detecting means includes the refrigerant detecting means. When the means detects the working refrigerant, the notification means notifies the working refrigerant, and the control means closes the second refrigerant blocking means based on the output of the state detecting means, collects the working refrigerant in the outdoor unit, and then collects the working refrigerant. When the refrigerant leakage determination process for determining the presence or absence of refrigerant leakage is performed and it is determined that there is no refrigerant leakage, the operation returns to the operation before the refrigerant detecting means detects the operating refrigerant.

As a result, the leakage of the working refrigerant can be minimized, and even when the refrigerant detecting means outputs the refrigerant detection output, the refrigerant leakage can be determined and appropriate operation and operation can be performed.

Therefore, even if the leakage of the working refrigerant is minimized and the refrigerant detecting means outputs the refrigerant detection output even though the working refrigerant is not leaking, the appropriate operation and operation can be performed. It is possible to provide an air conditioner having a small load, high safety and reliability, and high convenience.

The second invention uses the refrigerant temperature detecting means and the refrigerant pressure detecting means as the state detecting means in the first invention, and the refrigerant temperature detecting means and the refrigerant pressure detecting means are both the first. It is installed on the indoor side of the refrigerant circuit cut off by the refrigerant cutoff means and the second refrigerant cutoff means.

This makes it possible to accurately estimate the state of the operating refrigerant on the indoor unit side during the refrigerant recovery operation.

Therefore, the amount of the working refrigerant remaining in the refrigerant circuit of the indoor unit can be accurately determined.

According to a third aspect of the present invention, in the first and second inventions, the control means includes the refrigerant pressure detecting means, an indoor refrigerant temperature detecting means for detecting a refrigerant temperature in an indoor unit, and an indoor temperature detecting for detecting an indoor air temperature. The refrigerant leakage determination process is performed based on the output of the means.

Thereby, the state of the working refrigerant on the indoor side blocked by the first refrigerant blocking means and the second refrigerant blocking means can be accurately detected.

Therefore, the presence or absence of refrigerant leakage can be accurately determined in a short time.

In the fourth aspect of the invention, in the first to third inventions, the control means performs a safety assurance operation when it is determined as a result of the refrigerant leakage determination process that there is a refrigerant leak.

As a result, the leakage of the working refrigerant can be minimized and the safety of the room can be ensured.

Therefore, it is possible to provide a highly safe air conditioner.

Fifth Invention In the first to fourth inventions, when it is determined that there is no refrigerant leakage as a result of the refrigerant leakage determination processing, the output of the refrigerant detection means is normal. After that, the refrigerant detecting means returns to the operation before detecting the operating refrigerant, and when it is determined that there is a refrigerant leak as a result of the refrigerant leakage determination process, the output of the refrigerant detecting means becomes normal. Even after that, the operation does not return to the operation before the refrigerant detecting means detects the working refrigerant, and the notifying means notifies the leakage of the working refrigerant.

As a result, when the refrigerant detecting means outputs the refrigerant detection, the operation is prohibited if there is a refrigerant leak, and the normal operation is automatically restored if there is no refrigerant leak.

Therefore, excellent convenience can be realized without impairing safety and without bothering the user.

In the sixth invention, in the first to fifth inventions, the working refrigerant is a flammable refrigerant.

As a result, the impact on ozone layer depletion and global warming can be minimized.

Therefore, it is possible to provide an air conditioner that is safe and has a small environmental load.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 shows a configuration diagram of an air conditioner according to the first embodiment of the present invention.

As shown in FIG. 1, the air conditioner in the first embodiment is a device in which an outdoor unit 101 and an indoor unit 107 are connected in a ring shape by a pipe to circulate an operating refrigerant to perform cooling or heating.

The outdoor unit 101 is between a compressor 102 that compresses the working refrigerant, a four-way valve 103 that switches the flow of the working refrigerant discharged from the compressor 102, and the outdoor air and the working refrigerant sent by the outdoor blower 105. An outdoor heat exchanger 104 that exchanges heat and an expansion valve 106 that decompresses and expands a high-pressure working refrigerant are provided. Incidentally, the compressor 102 is an inverter drive type compressor, and the operating rotation speed can be changed according to the situation.

The indoor unit 107 is provided with an indoor heat exchanger 108 that exchanges heat between the indoor air sent by the indoor blower 109 and the working refrigerant, and cools and heats the room in order to make the room comfortable. ..

The indoor unit 107 is connected by piping at the liquid side connection port 110 and the gas side connection port 111 of the outdoor unit 101 to form a basic refrigerant circuit. In addition, in order to perform comfortable air conditioning and smooth operation, a room temperature sensor 116, an indoor refrigerant temperature sensor 117, an outside air temperature sensor 118, a compressor power sensor 119, and a control device 120 as control means are provided.

The control device 120 receives the output of all the sensors and outputs an operation command to all the operation elements. In FIG. 1, the sensor output 123 and the operation command 124 are represented by arrows, and the individual correspondence is shown. Is omitted. The control means can control, for example, the liquid side shutoff valve 112, the gas side shutoff valve 113, and the compressor 102.

The air conditioner of FIG. 1 has a state detecting means, and the state detecting means may be any detecting means for estimating the state of the operating refrigerant of the indoor unit, for example, a refrigerant temperature detecting means and a refrigerant pressure. Examples thereof include a detecting means, a temperature detecting means, and a compressor power detecting means, and preferably, at least two or more of them are installed. The refrigerant temperature detecting means is a means for detecting the temperature of the working refrigerant flowing in the refrigerant circuit, and in FIG. 1, the refrigerant temperature sensor 114 and the indoor refrigerant temperature sensor 117 correspond to this. The refrigerant pressure detecting means is a means for detecting the pressure of the operating refrigerant in the refrigerant circuit, and in FIG. 1, the pressure sensor 115 corresponds to this. The air temperature detecting means is a means for detecting the atmospheric temperature of the outdoor unit 101 or the indoor unit 107, and in FIG. 1, the outdoor air temperature sensor 118 and the room temperature sensor 116 correspond to this. The compressor power detecting means is a means for detecting the power consumption of the compressor 102, and in FIG. 1, the compressor power sensor 119 corresponds to this.

The working refrigerant to be used is not particularly limited, and any working refrigerant that can be used for freezing or forming a heat pump by using a compressor by utilizing the absorption and heat dissipation accompanying the phase change can be used.

Further, in the air conditioner of FIG. 1, in order to minimize the leakage of the working refrigerant to improve safety and reduce the environmental load, the refrigerant recovery operation is appropriate when the operation is stopped, for example, at the end of the operation or when the working refrigerant leaks. To do. Therefore, a refrigerant shutoff means is provided, and a liquid side shutoff valve 112 is arranged as a first refrigerant shutoff means between the expansion valve 106 which is the first refrigerant path and the liquid side connection port 110, and the liquid side shutoff valve is provided. A refrigerant temperature sensor 114 is arranged between the 112 and the liquid side connection port 110. In addition, a gas side shutoff valve 113 is arranged as a second refrigerant shutoff means between the gas side connection port 111 and the four-way valve 103, which are the second refrigerant paths, and is between the gas side connection port 111 and the gas side shutoff valve 113. A pressure sensor 115 is arranged in the indoor unit 107, and a refrigerant sensor 125 as a refrigerant detecting means and a speaker 126 as a notifying means are arranged in the indoor unit 107.

In FIG. 1, the four-way valve 103 is in a state during cooling operation, defrosting operation, or refrigerant recovery operation, and the working refrigerant discharged from the compressor 102 is sent from the four-way valve 103 to the outdoor heat exchanger 104 and then to the outdoor heat exchanger 104. It constitutes a refrigeration cycle that flows to the expansion valve 106, the liquid side shutoff valve 112, the liquid side connection port 110, and the indoor heat exchanger 108.

In the case of heating operation, the working refrigerant discharged from the compressor 102 is sent from the four-way valve 103 to the indoor heat exchanger 108 via the gas side shutoff valve 113 and the gas side connection port 111, and then to the liquid side connection port 110 and the liquid. It constitutes a heat pump cycle that flows to the side shutoff valve 112 and the outdoor heat exchanger 104.

In order to recover the working refrigerant to the outdoor unit 101 using the compressor 102, it is necessary to configure and operate the refrigeration cycle.

When the refrigerant recovery operation is instructed by the control device 120, the rotation speed of the compressor 102 is set to a predetermined value, and the refrigerant recovery operation is performed. After temporarily stopping during the heating operation, the setting of the four-way valve 103 is set in the same way as during the cooling operation, and the refrigerant recovery operation is started. During the operation in the refrigerating cycle in which the indoor heat exchanger 108 flows in this order via 104, the refrigerant recovery operation is continuously advanced without stopping.

When the liquid side shutoff valve 112 is closed after shifting to the refrigerant recovery operation and a predetermined time has elapsed, the supply of the working refrigerant into the refrigerant circuit of the indoor unit 107 is stopped, and the compressor 102 continues to operate. The working refrigerant in the refrigerant circuit of the above is sucked and collected in the refrigerant circuit of the outdoor unit 101, and most of them are condensed and stored in the outdoor heat exchanger 104.

As the refrigerant recovery operation progresses, the output of the pressure sensor 115 decreases, and the outputs of the refrigerant temperature sensor 114 and the indoor refrigerant temperature sensor 117 decrease, but when the liquid refrigerant in the detection unit runs out, the output starts to increase and the ambient temperature is increased. It slowly rises to the upper limit.

The change in the output of the refrigerant temperature sensor 114 and the indoor refrigerant temperature sensor 117 proceeds faster in the indoor refrigerant temperature sensor 117, reaches the lowest value first, and starts to rise. The refrigerant temperature sensor 114 is the furthest from the suction port of the compressor 102, and the output change reaches the lowest value at the latest.

Although a decrease in pressure can be detected only by the output of the pressure sensor 115, how much liquid refrigerant remains in the refrigerant circuit of the indoor unit 107 is not always the same depending on the installation state and the difference in room temperature. ..

It is difficult to make a judgment only by the output of one of the refrigerant temperature sensor 114 or the indoor refrigerant temperature sensor 117, and even if it is determined by the output value of the indoor refrigerant temperature sensor 117, the liquid depends on the installation state and operating condition of the liquid side connection pipe 121. It is difficult to determine how much liquid refrigerant remains between the side connection pipe 121 and the liquid side shutoff valve 112. When judging only by the output of the refrigerant temperature sensor 114, there is a high possibility that the inside of the refrigerant circuit of the indoor unit 107 becomes a negative pressure after confirming the minimum output value.

If a large amount of liquid refrigerant remains, there is a risk of ignition if it leaks, and conversely, if the pressure inside the refrigerant circuit becomes negative, air will be mixed in and a diesel explosion will occur inside the compressor 102. Or, if oxygen or moisture adversely affects the reliability of the device, or if an external force is applied to the liquid side connection pipe 121 or gas side connection pipe 122 that has become negative pressure due to some work, deformation easily occurs. There is a risk of getting rid of it.

Therefore, instead of determining the refrigerant recovery end timing with a single sensor output, if the refrigerant recovery end timing is determined comprehensively from a plurality of sensor outputs, the residual amount of refrigerant in the refrigerant circuit of the indoor unit 107 can be determined. It can be controlled accurately.

Further, in the first embodiment, the compressor 102 is provided with the compressor power sensor 119, and when the refrigerant recovery operation proceeds, the compressor power sensor 119 is provided even if the rotation speed of the compressor 102 is constant. The output of is reduced. Although the compressor power sensor 119 is inferior in accuracy, it is often mounted on the compressor 102 for protection control, and can be configured at low cost.

Further, even when the pressure sensor 115 is used, the compressor power sensor 119 can serve as a substitute even if a defect occurs in the pressure sensor 115, and high reliability can be obtained.

Here, a combination of sensors and an actual example of the refrigerant recovery operation will be described.

First, as a basic combination, a combination of the pressure sensor 115 as the refrigerant pressure detecting means and the refrigerant temperature sensor 114 or the indoor refrigerant temperature sensor 117 as the refrigerant temperature detecting means can be considered.

After the start of the refrigerant recovery operation, the output of the pressure sensor 115 gradually decreases. At this time, the refrigerant recovery operation is basically completed by reducing the amount of liquid refrigerant in the refrigerant circuit in the indoor unit 107 as much as possible before the output of the pressure sensor 115 becomes a negative pressure.

As the refrigerant recovery operation progresses, the output of the pressure sensor 115 decreases, and the output of the refrigerant temperature sensor 114 or the indoor refrigerant temperature sensor 117 also decreases. Before the output of the pressure sensor 115 becomes negative pressure, when the output of the refrigerant temperature sensor 114 or the indoor refrigerant temperature sensor 117 starts to rise, when the output of the pressure sensor 115 reaches a predetermined value, the refrigerant recovery is completed and the gas is recovered. The side shutoff valve 113 is closed, and the compressor 102, the outdoor blower 105, and the indoor blower 109 are stopped.

The refrigerant temperature sensor 114 and the indoor refrigerant temperature sensor 117 are superior from the viewpoint of accurately recovering the refrigerant, but the indoor refrigerant temperature sensor 117 is generally arranged for the purpose of controlling the air conditioner. It is also possible to substitute a pipe temperature sensor, and in many cases, the increase in cost can be suppressed.

Further, if the compressor power sensor 119 is used as the compressor power detection means instead of the pressure sensor 115, the detection accuracy of the refrigerant pressure is lowered, but the current value is used for the control in the compressor such as the one using the DC brushless motor. Since it can be detected without any special cost, it is possible to suppress the increase in cost.

Immediately after the start of the refrigerant recovery operation, the refrigerant recovery to the outdoor unit 101 has not yet progressed, and when the pressure of the suction refrigerant of the compressor 102 is high, the power of the compressor 102 is also high, but the refrigerant recovery is performed. If the pressure of the suction refrigerant of the compressor 102 decreases, the power of the compressor also decreases. Therefore, the output of the pressure sensor 115 can be replaced with the output of the compressor power sensor 119, and the progress state of the refrigerant recovery can be estimated in the same manner.

Further, an appropriate refrigerant recovery operation can be performed by using the pressure sensor 115 or the compressor power sensor 119, the room temperature sensor 116 and the outside air temperature sensor 118 as the temperature detecting means, and the refrigerant temperature sensor 114 or the indoor refrigerant temperature sensor 117. It is possible.

By using the outputs of the room temperature sensor 116 and the outside air temperature sensor 118, the temperature of the working refrigerant in the outdoor room can be estimated together with the rotation speed of the compressor 102, and the power consumption of the compressor 102 can be estimated.

If the air conditioner is normal, the output value of the compressor power sensor 119 generally matches the estimated value of power consumption, but if the circulation of the refrigerant is stopped or the heat exchange with the indoor or outdoor air is hindered. , A big discrepancy occurs.

At the time of refrigerant recovery, the circulation of the refrigerant is stopped by the liquid side shutoff valve 112, so that the output value of the compressor power sensor 119 decreases and becomes smaller than the estimated value as the refrigerant recovery progresses.

By comparing the estimated power consumption of the compressor 102 with the output value of the compressor power sensor 119, the progress of refrigerant recovery can be estimated more accurately.

Here, if the shape of the mounting portion of the indoor refrigerant temperature sensor 117 and the refrigerant temperature sensor 114 is such that, for example, the refrigerant vertically descends and then rises vertically, and the structure is such that the liquid refrigerant can easily be stored, the evaporation of the liquid refrigerant is completed. Can be detected more accurately.

In addition, the refrigerant temperature sensor 114 and the pressure sensor 115 are preferably arranged on the refrigerant circuit side of the indoor unit 107 for the purpose of accurately recovering the refrigerant. The mounting position of the refrigerant temperature sensor 114 captures the moment when the final liquid refrigerant evaporates when the liquid refrigerant remains until the end, that is, between the liquid side connection port 110 and the liquid side shutoff valve 112. be able to. The pressure sensor 115 is installed on the refrigerant circuit side of the indoor unit 107 between the gas side connection port 111 and the gas side shutoff valve 113, which are closest to the suction port of the compressor 102, to detect the minimum pressure. Can be done.

That is, by arranging the refrigerant temperature sensor 114 and the pressure sensor 115 at the positions shown in FIG. 1, the refrigerant can be recovered most accurately. Further, in the first embodiment, when the refrigerant sensor 125 detects the working refrigerant as the refrigerant detecting means, it is considered that the working refrigerant in the apparatus is leaking, but the working refrigerant is not actually leaking. However, there is a possibility that the refrigerant sensor 125 outputs a refrigerant detection level.

There are several types of refrigerant sensors, and the one that is suitable for the type of gas to be detected is used.

Here, in the situation where the device is actually used, even if the gas has a component different from that of the working refrigerant, the sensor may react, or the gas containing the same component as the working refrigerant is sprayed. In some cases, it is used as a gas, and just because the sensor reacts does not necessarily mean that the working refrigerant is leaking.

However, since the possibility that the working refrigerant is leaking cannot be denied, it is necessary to perform operations for preventing refrigerant leakage and avoiding danger.

Therefore, in the air conditioner of the first embodiment, when the refrigerant sensor 125 outputs the refrigerant detection level, when the air conditioning operation is performed, the speaker 126 first notifies that the refrigerant gas has been detected, and the refrigerant recovery operation is performed. And stop the compressor 102, leaving a predetermined amount of refrigerant in the refrigerant circuit on the indoor unit 107 side as described above.

As the notification means of the first embodiment, the speaker 126 is installed, and when the refrigerant sensor 125 detects the refrigerant, it notifies that the refrigerant is detected by a warning sound, a voice, or the like, or that the refrigerant is leaking. Will be done. As the notification means, it suffices to notify the user that the refrigerant has been detected or that the refrigerant has leaked, and it is also possible to emit light such as an LED to notify the user. Further, the notification means is not limited to that installed in the air conditioner, and may be installed in other equipment or the like. For example, it may be attached to the remote controller, or may be displayed on the display unit of the remote controller. Further, it may be displayed on a notification or display unit by a speaker such as a smartphone in which a signal is transmitted via a public line such as the Internet.

Next, the refrigerant leakage determination process is performed. Even if the user stops the operation during the refrigerant leakage determination process, the refrigerant leak determination process continues and the operating state of the air conditioner is stopped.

In the refrigerant leakage determination process, the output of the pressure sensor 115 as the refrigerant pressure detecting means, the room temperature sensor 116 as the indoor temperature detecting means, and the indoor refrigerant temperature sensor 117 as the indoor refrigerant temperature detecting means are used in the refrigerant pipe on the indoor unit 107 side. The amount of working refrigerant is calculated, and the change in the calculated working refrigerant amount within a predetermined time is monitored to determine the presence or absence of refrigerant leakage.

The amount of the working refrigerant can be easily calculated from the outputs of the pressure sensor 115 and the indoor refrigerant temperature sensor 117 and the volume of the refrigerant pipe on the indoor unit 107 side if the working refrigerant is stable in a single phase.

The volume of the refrigerant pipe on the indoor unit 107 side differs depending on the installed state of the air conditioner, but it does not change after installation. You may.

However, since it is not thermally stable immediately after the refrigerant is recovered, the error becomes large if the temperature is determined only by the output of the indoor refrigerant temperature sensor 117 and the amount of the working refrigerant is calculated until it becomes stable.

Therefore, if the thermal stability is determined by using the output of the room temperature sensor 116 and the representative temperature is calculated from the outputs of the room temperature sensor 116 and the indoor refrigerant temperature sensor 117, the waiting time can be shortened and the accurate amount of working refrigerant can be obtained. Can be calculated.

As a result, accurate refrigerant leakage determination processing can be performed in a short time.

Then, if it is determined that "there is a refrigerant leak", the safety assurance operation is started, and the speaker 126 notifies the user of the refrigerant leak and requests maintenance. If the notification of the refrigerant leakage and the maintenance request by the speaker 126 are continued more than necessary, noise will be generated. Therefore, the speaker 126 is repeated for a predetermined time or a predetermined number of times and then stopped. At this time, most of the refrigerant is recovered in the outdoor unit 101, and only the minimum amount of refrigerant remains in the refrigerant circuit on the indoor unit 107 side, so that the safety in the room is ensured.

If the user attempts to operate the air conditioner while the "refrigerant leak is present", the air conditioner will be notified of the refrigerant leak again and maintenance will be requested, and the maintenance will be completed and the alarm will be canceled. Do not drive until.

It is effective to make a sound or voice notification as well as a visual notification using an LED or a display device. In the case of visual announcements, keeping the announcements will encourage early response.

Then, if it is determined as "no refrigerant leakage" as a result of the refrigerant leakage determination processing, the determination result is notified and the alarm is canceled, and after the output of the refrigerant detection level of the refrigerant sensor 125 becomes normal, the refrigerant sensor 125 is used. Returns to the operating state before detecting the refrigerant. If you are making a visual announcement, stop the announcement.

If the refrigerant sensor 125 is stopped when the refrigerant detection level is output, the refrigerant has already been recovered. Therefore, after notifying that the refrigerant gas has been detected, the refrigerant leakage determination process is started, and then the same as above is performed. A safety assurance operation or a recovery operation is performed according to the determination result.

FIG. 2 shows a flowchart of the process after the refrigerant is detected.

Even if refrigerant leakage occurs, if the amount of leakage per hour is small, it may not be possible to detect it with the refrigerant sensor 125, but when the air conditioner is stopped, the leakage is determined and the indoor unit 107 side. If the calculated amount of refrigerant enclosed in the refrigerant circuit is stored, and the calculated amount of refrigerant enclosed immediately before restarting the operation is recalculated and compared, it can be detected before the operation.

As described above, the air conditioner of the first embodiment determines the presence or absence of refrigerant leakage when the refrigerant sensor 125 detects the refrigerant, and performs an appropriate operation according to the presence or absence of the refrigerant leakage. It is possible to reduce the burden on the air conditioner and provide an air conditioner with excellent convenience.

The air conditioner shown in the first embodiment of FIG. 1 can minimize the leakage of the refrigerant, prevent the suction of air, improve the safety, and reduce the environmental load when any refrigerant is used. Although it is possible, when a flammable refrigerant such as R32, R1234yf, R1234ze, or a hydrocarbon such as propane or butane is used, it leads to avoiding danger such as ignition, and its effect is great.

Among them, propane has not only a small influence on global warming but also excellent performance as a refrigerant, and the significance of the present invention capable of reducing the risk of ignition is extremely high.

As described above, the air conditioner according to the present invention prevents leakage of the working refrigerant in an air conditioner that performs air conditioning using a refrigerating and heat pump cycle, and the technique is not limited to the air conditioner. It can be widely applied to water conditioners, showcases, refrigerators, etc., and has an effect.

101 Outdoor unit 102 Compressor 103 Four-way valve 104 Outdoor heat exchanger 105 Outdoor blower 106 Expansion valve 107 Indoor unit 108 Indoor heat exchanger 109 Indoor blower 110 Liquid side connection port 111 Gas side connection port 112 Liquid side shutoff valve 113 Gas side shutoff Valve 114 Refrigerant temperature sensor 115 Pressure sensor 116 Room temperature sensor 117 Indoor refrigerant temperature sensor 118 Outside temperature sensor 119 Compressor power sensor 120 Control device 121 Liquid side connection pipe 122 Gas side connection pipe 123 Sensor output 124 Operation command 125 Refrigerant sensor 126 Speaker

Claims (6)

A compressor that compresses and sends out the working refrigerant, and an outdoor unit having an outdoor heat exchanger that exchanges heat between the outdoor air sent by the outdoor blower and the working refrigerant.
An indoor unit having an indoor heat exchanger that exchanges heat between the indoor air sent by the indoor blower and the working refrigerant.
An air conditioner that constitutes a freezing or heat pump cycle.
A first refrigerant blocking means for blocking the first refrigerant path connecting the outdoor unit and the indoor unit,
A second refrigerant blocking means for blocking the second refrigerant path connecting the outdoor unit and the indoor unit,
A state detecting means for estimating the state of the operating refrigerant of the indoor unit, and
Refrigerant detection means to detect working refrigerant and
The notification means for notifying that the refrigerant detecting means has detected the working refrigerant, and
Equipped with control means to control the operation of the device
The state detecting means includes at least two or more of a refrigerant temperature detecting means, a refrigerant pressure detecting means, a temperature detecting means, and a compressor power detecting means.
When the refrigerant detecting means detects the working refrigerant, the notification means notifies the working refrigerant, and the control means closes the second refrigerant blocking means based on the output of the state detecting means and collects the working refrigerant in the outdoor unit. After that, a refrigerant leakage determination process for determining the presence or absence of refrigerant leakage is performed, and when it is determined that there is no refrigerant leakage, the air conditioning is returned to the operation before the refrigerant detecting means detects the operating refrigerant. Machine. The refrigerant temperature detecting means and the refrigerant pressure detecting means are used as the state detecting means, and the refrigerant temperature detecting means and the refrigerant pressure detecting means are both the first refrigerant blocking means and the second refrigerant blocking means. The air conditioner according to claim 1, wherein the air conditioner is installed on the indoor side of the refrigerant circuit cut off by. The control means performs the refrigerant leakage determination process based on the outputs of the refrigerant pressure detecting means, the indoor refrigerant temperature detecting means for detecting the refrigerant temperature in the indoor unit, and the indoor temperature detecting means for detecting the indoor air temperature. The air conditioner according to claim 1 or 2, wherein the air conditioner is characterized. The air conditioner according to any one of claims 1 to 3, wherein the control means performs a safety assurance operation when it is determined that there is a refrigerant leak as a result of the refrigerant leakage determination process. .. When it is determined that there is no refrigerant leakage as a result of the refrigerant leakage determination process, the control means operates after the output of the refrigerant detecting means becomes normal and before the refrigerant detecting means detects the operating refrigerant. If it is determined that there is a refrigerant leak as a result of the refrigerant leakage determination process, the operation is performed even after the output of the refrigerant detecting means becomes normal but before the refrigerant detecting means detects the working refrigerant. The air conditioner according to any one of claims 1 to 4, wherein the notification means does not return, and the notification means notifies the leakage of the working refrigerant. The air conditioner according to any one of claims 1 to 5, wherein the working refrigerant is a flammable refrigerant.

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