Air Conditioner

This application is a continuation of International Application No. PCT/JP2023/006998, filed Feb. 27, 2023, the entire contents of which are incorporated herein by reference.

The present invention relates to an air conditioner technology.

There is an air conditioner including a refrigerant shutoff valve. For example, Patent Document 1 discloses an air conditioner in which a mechanism for shutting off a flow of a refrigerant flowing through a liquid refrigerant pipe and a gas refrigerant pipe is provided in the liquid refrigerant pipe and the gas refrigerant pipe connecting an outdoor unit including a compressor and a plurality of indoor units including an indoor expansion valve and an indoor heat exchanger, and the shutoff mechanism operates when the refrigerant leaks from the indoor unit side to suppress a refrigerant leak from the indoor unit side.

In the technology disclosed in Patent Document 1, in order to confirm an operation of the shutoff mechanism including its shutoff performance, the compressor is operated in a cooling cycle state and the shutoff mechanism is opened and closed to determine whether or not the shutoff mechanism is operating normally including the shutoff performance.

Hereinafter, an air conditioner of an embodiment will be described with reference to the drawings.

An air conditioner according to an embodiment includes: an outdoor unit that includes an outdoor expansion valve, an outdoor heat exchanger, a four-way valve, and a compressor; an indoor unit that includes an indoor heat exchanger and an indoor expansion valve that adjusts an amount of a refrigerant flowing through the indoor heat exchanger; a shutoff unit that connects the outdoor unit and the indoor unit in parallel to the same refrigerant piping system, either singly or in a plurality of connections, and that incorporates a plurality of shutoff mechanisms configured to shut off a flow of the refrigerant between the outdoor unit and the indoor unit; and a refrigerant leak detector electrically connected to the indoor unit.

The shutoff unit is connected to the outdoor unit via at least one liquid pipe through which a liquid refrigerant flows and at least one gas pipe through which a gas refrigerant flows, and is connected to the indoor unit via at least one liquid pipe through which the liquid refrigerant flows and at least one gas pipe through which the gas refrigerant flows, and the air conditioner includes: a simple inspection mode for confirming a refrigerant leak detection operation of the refrigerant leak detector; and a detailed inspection mode for confirming, by operating the compressor, that each of the plurality of shutoff mechanisms incorporated in the shutoff unit is operating normally, and is capable of selectively executing the simple inspection mode and the detailed inspection mode.

is a diagram showing a configuration of an air conditioneraccording to the present embodiment. Note that,shows one outdoor unit and three indoor units as an example, but the number of units is not limited thereto. Also, the refrigeration cycle ofis an example, and the invention is not limited to the refrigeration cycle. The air conditionerincludes indoor units,,and an outdoor unit. Also, the outdoor unitis configured to be connected to the indoor units,anddisposed in parallel by refrigerant piping. In the outdoor unit, a compressor, a four-way valvefor switching between cooling and heating operations, an outdoor heat exchanger, and an outdoor expansion valveare connected by refrigerant piping. Also, the outdoor unitincludes an outdoor blowerfor promoting heat exchange of a refrigerant. The outdoor unitincludes an outdoor unit control unitthat performs various controls of the air conditioner.

The indoor unitis constituted by an indoor expansion valve, an indoor heat exchanger, a temperature sensor, an indoor blower, an indoor unit control unit, and a leak detector. The indoor heat exchangerand the indoor expansion valveare connected by refrigerant piping. Also, the indoor unitis electrically connected to the leak detector. The outdoor expansion valveand the indoor expansion valveare connected by liquid refrigerant piping. A liquid refrigerant shutoff valveis provided between the indoor expansion valveand the outdoor expansion valve. Also, the indoor heat exchangerand the four-way valveare connected by gas refrigerant piping, and a gas refrigerant shutoff valveis provided between the indoor heat exchangerand the four-way valve.

The indoor unitis constituted by an indoor expansion valve, an indoor heat exchanger, a temperature sensor, an indoor blower, an indoor unit control unit, and a leak detector. The indoor heat exchangerand the indoor expansion valveare connected by refrigerant piping. Also, the indoor unitis electrically connected to the leak detector. The outdoor expansion valveand the indoor expansion valveare connected by liquid refrigerant piping. A liquid refrigerant shutoff valveis provided between the indoor expansion valveand the outdoor expansion valve. Also, the indoor heat exchangerand the four-way valveare connected by gas refrigerant piping, and a gas refrigerant shutoff valveis provided between the indoor heat exchangerand the four-way valve.

The indoor unitis constituted by an indoor expansion valve, an indoor heat exchanger, a temperature sensor, an indoor blower, an indoor unit control unit, and a leak detector. The indoor heat exchangerand the indoor expansion valveare connected by refrigerant piping. Also, the indoor unitis electrically connected to the leak detector. The outdoor expansion valveand the indoor expansion valveare connected by liquid refrigerant piping. A liquid refrigerant shutoff valveis provided between the indoor expansion valveand the outdoor expansion valve. Also, the indoor heat exchangerand the four-way valveare connected by gas refrigerant piping, and a gas refrigerant shutoff valveis provided between the indoorheat exchangerand the four-way valve.

The outdoor unit control unitis capable of communicating with the indoor unit control units,, anddescribed above. As for a communication method, a general-purpose protocol such as, for example, Modbus may be used. The liquid refrigerant shutoff valves,, and, and the gas refrigerant shutoff valves,, andare opened and closed under the control of the outdoor unit control unit. Also, detection results of the leak detectors,, andare notified to the outdoor unit control unitvia the indoor unit control units,, and.

Functions executed by the outdoor unit control unitand the indoor unit control units,, andare realized by, for example, a hardware processor such as a central processing unit (CPU) executing a program (software). Some or all of these components may be realized by hardware (circuit unit including a circuitry) such as a large scale integration (LSI), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), and a graphics processing unit (GPU), or may be realized by software and hardware in cooperation. The program may be stored in advance in a storage device (storage device including a non-transitory storage medium) such as a hard disk drive (HDD), a solid state drive (SSD), or a flash memory, or may be stored in a detachable storage medium (non-transitory storage medium) such as a DVD or a CD-ROM and installed by mounting the storage medium on a drive device. An operation unit that is not shown in the drawings and receives an operation by an inspector is provided in the outdoor unit control unitand the indoor unit control units,, and.

In the configuration shown in, one leak detector is provided for each indoor unit, but it is not necessarily required for the indoor unit and the leak detector to be a one-to-one pair. Also, any of the liquid refrigerant shutoff valves,, andand the gas refrigerant shutoff valves,, andmay be in a form of an electric valve whose opening is variable and capable of shutting off a flow of the refrigerant, or in a form of a solenoid valve that switches between an open state and a closed state.

As shown indescribed above, the air conditionerincludes: the outdoor unitthat includes the outdoor expansion valve, the outdoor heat exchanger, the four-way valve, and the compressor; the indoor units,, andthat includes the indoor heat exchangers,, and, and the indoor expansion valves,, andthat adjust an amount of the refrigerant flowing through the indoor heat exchangers,, and; the shutoff unit that connects the outdoor unitand the indoor units,, andin parallel to the same refrigerant piping system, either singly or in a plurality of connections, and that incorporates a plurality of shutoff mechanisms (the liquid refrigerant shutoff valves,, and, and the gas refrigerant shutoff valves,, and) capable of shutting off a flow of the refrigerant between the outdoor unitand the indoor units,, and; and the refrigerant leak detectors (leak detectors,, and) electrically connected to the indoor units,, and. There are three shutoff units corresponding to (the liquid refrigerant shutoff valveand the gas refrigerant shutoff valve), (the liquid refrigerant shutoff valveand the gas refrigerant shutoff valve), and (the liquid refrigerant shutoff valveand the gas refrigerant shutoff valve).

is a diagram showing a configuration of the leak detectors,, and. The leak detectors,, andeach include a simple inspection mode execution button, an alarm light emitting diode (LED), an alarm buzzer, and a refrigerant leak sensor. The simple inspection mode execution buttonis a button operated by the inspector or the like. It is constituted by a refrigerant leak sensor. The simple inspection mode execution buttonis a button for checking whether or not the alarm LEDlights up and whether or not the alarm buzzeractivates an alarm. If there is a problem with the alarm LED, the alarm LEDwill not emit light even if the simple inspection mode execution buttonis operated. Similarly, if there is a problem with the alarm buzzer, the alarm buzzerwill not activate an alarm even if the simple inspection mode execution buttonis operated.

The alarm LEDis an LED that lights up when a leak is detected by the refrigerant leak sensoror when the simple inspection mode execution buttonis operated. The alarm buzzeris a buzzer that activates an alarm when a leak is detected by the refrigerant leak sensoror when the simple inspection mode execution buttonis operated. The refrigerant leak sensoris a sensor for detecting a leak of the refrigerant in the indoor units,, and.

is a flowchart showing a flow of processing executed by the outdoor unit control unit, the indoor unit control units,, and, and the leak detectors,, and. In, when the outdoor unit control unitreceives an operation to start an outdoor unit detailed inspection mode via the operation unit (step S: YES), it determines whether or not the air conditioneris in operation (step S). If the air conditioneris not in operation (step S: NO), the processing proceeds to step S. If the air conditioneris in operation (step S: YES), the outdoor unit control unitstops the operation (step S), and the processing proceeds to step S.

The outdoor unit control unitstarts an inspection operation of the shutoff valves (the liquid refrigerant shutoff valves,, andand the gas refrigerant shutoff valves,, and) (step S). The inspection operation of the shutoff valves is an operation for confirming whether or not the piping is correctly connected by opening and closing the shutoff valves. Next, it is determined whether or not an operation to start the simple inspection mode of the leak detector has been received in any of the indoor unit control units,, and(step S).

The simple inspection mode is a mode in which the inspector operates the inspection mode execution button, confirms that the alarm LEDlights up and the alarm buzzeractivates an alarm, and inputs whether or not there is an abnormality in the alarm LEDand whether or not there is an abnormality in the alarm buzzerinto the indoor unit control unit.

Furthermore, when the indoor unit control unitreceives an operation to start the simple inspection mode, a target of the simple inspection mode is the leak detector. When the indoor unit control unitreceives an operation to start the simple inspection mode, a target of the simple inspection mode is the leak detector. When the indoor unit control unitreceives an operation to start the simple inspection mode, a target of the simple inspection mode is the leak detector.

If the operation to start the simple inspection mode has not been received (step S: NO), the processing proceeds to step S. When the operation to start the simple inspection mode has been received (step S: YES), it is determined whether or not an input indicating no abnormality has been received for the alarm LED(step S). If an input indicating an abnormality is received (step S: NO), the indoor unit control unitconfirms the abnormality (step S), and the processing proceeds to step S.

If an input indicating no abnormality is received (step S: YES), the indoor unit control unitdetermines whether or not an input indicating no abnormality has been received for the alarm buzzer(step S). If an input indicating an abnormality is received (step S: NO), the indoor unit control unitconfirms the abnormality (step S), and the processing proceeds to step S.

If an input indicating no abnormality is received (step S: YES), the outdoor unit control unitdetermines whether or not an input indicating no abnormality of the shutoff valve has been received by the inspector (step S). If an input indicating an abnormality is received (step S: NO), the outdoor unit control unitconfirms the abnormality (step S) and stops the operation (step S). If an input indicating no abnormality is received (step S: YES), the outdoor unit control unitstops the operation as is (step S).

As described above, the first embodiment has a simple inspection mode for confirming the refrigerant leak detection operation of the leak detector (,, and) and a detailed inspection mode for confirming, by operating the compressor, that each of the plurality of shutoff mechanisms incorporated in the shutoff unit is operating normally, and the simple inspection mode and the detailed inspection mode can be selectively executed.

Then, when the simple inspection mode is performed in parallel while the detailed inspection mode is being performed, it is possible to reduce the time required to determine whether or not the shutoff valve and the refrigerant leak detector are operable. Also, when the detailed inspection mode is started by operating the outdoor unit and the simple inspection mode is started by operating the leak detector, it is possible to improve convenience for the inspector.

In a second embodiment, a form in which an inspection target unit to be inspected within one system is divided into two or more groups and inspected will be described. The grouping will be specifically described with reference to the drawings.is a diagram showing an example of grouping. The configuration shown inis the same as the configuration shown in, and therefore descriptions of respective portions will be omitted.

The grouping shown inshows a form in which units are divided into two groups (Grand Gr). The inspection target unit described above is configured by an indoor unit, a liquid refrigerant shutoff valve, and a gas refrigerant shutoff valve. A configuration including these three is regarded as one inspection target unit. Then, in the present embodiment, grouping is performed such that there is at least one group including two or more inspection target units. Therefore, for example, if there are five inspection target units, grouping is conceivable that two groups each including two inspection target units and one group including a single inspection target unit, one group including two inspection target units and two groups each including a single inspection target unit, or one group including three inspection target units and one group including two inspection target units.

After the grouping is performed in advance in this manner, a unit inspection mode is performed to confirm that each of the plurality of shutoff mechanisms incorporated in the inspection target unit is operating normally.is a flowchart showing a flow of the unit inspection mode. Furthermore, the processing shown inis based on the grouping shown in.

In, when an outdoor unit control unitreceives an operation to start the unit inspection mode via the operation unit (step S: YES), it determines whether or not an air conditioneris in operation (step S). If the air conditioneris not in operation (step S: NO), the processing proceeds to step S. If the air conditioneris in operation (step S: YES), the outdoor unit control unitstops the operation (step S), and the processing proceeds to step S.

The outdoor unit control unitcloses a liquid refrigerant shutoff valveof Grto be inspected (step S), and starts the operation (step S). At this time, shutoff valves of Gr(liquid refrigerant shutoff valvesand, and gas refrigerant shutoff valvesand) are open, and a cooling operation or heating operation is performed. Once the operation state has stabilized, the outdoor unit control unitconfirms that the liquid refrigerant shutoff valveis closed using a temperature sensorinstalled in an indoor heat exchanger(step S).

After confirming that the liquid refrigerant shutoff valveis operating normally, the outdoor unit control unitopens the liquid refrigerant shutoff valve(step S), closes a gas refrigerant shutoff valve(step S), and confirms that the gas refrigerant shutoff valveis closed using the temperature sensor(step S). After confirming that the gas refrigerant shutoff valveis operating normally, the outdoor unit control unitopens the gas refrigerant shutoff valve(step S), and the processing proceeds to an inspection of Gr.

During the inspection of Gr, shutoff valves of Gr(the liquid refrigerant shutoff valveand the gas refrigerant shutoff valve) are open, and an indoor unitcontinues a cooling operation or heating operation. Once the operation state has stabilized, the outdoor unit control unitcloses the liquid refrigerant shutoff valvesand(step S) and confirms that the liquid refrigerant shutoff valvesandare closed using temperature sensorsandinstalled in indoor heat exchangersand(step S). After confirming that the liquid refrigerant shutoff valvesandare operating normally, the outdoor unit control unitopens the liquid refrigerant shutoff valvesand(step S), closes the gas refrigerant shutoff valvesand(step S), and confirms that the gas refrigerant shutoff valvesandare closed using the temperature sensorsand(step S). After confirming that the gas refrigerant shutoff valvesandare operating normally, the outdoor unit control unitopens the gas refrigerant shutoff valvesand(step S) and ends the unit inspection mode.

By grouping the inspection target units to be inspected in this manner, it is possible to reduce an inspection time.

The following will provide additional statements regarding the second embodiment.

An air conditioner including:

The air conditioner according to additional statement 1, in which when the inspection mode is performed, a group not being inspected performs either a cooling operation, a heating operation, or a simultaneous cooling and heating operation.

The air conditioner according to additional statement 1, in which the grouping divides the number of indoor units included in the inspection target unit into a substantially equal number of units.

The air conditioner according to additional statement 1, in which the grouping is divided such that a total capacity of the indoor units to which the inspection target unit is connected is substantially equal.

The air conditioner according to additional statement 1, in which a determination of normality of the inspection target unit is performed by an indoor unit temperature sensor downstream of the shutoff unit.

As described above, according to the present embodiment, it is possible to provide a technology capable of suppressing discomfort given to a subject.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.