air conditioner

Abstract

To inexpensively suppress refrigerant leakage at power failure.SOLUTION: An air conditioner according to an embodiment includes a valve driving section for operating a valve provided on a refrigerant circuit, a control section for controlling the valve driving section, a power source section which receives power supply from the outside to generate DC voltage and outputs the DC voltage to a first path and a second path, and a power storage section which receives the DC voltage from the power source section and stores the DC voltage. The first path is a path for supplying the DC voltage output from the power source section to the valve driving section without passing through the power storage section. The second path is a path for supplying the DC voltage output from the power source section to the valve driving section through the power storage section.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an air conditioner. [Background technology]

[0002] Conventionally, in air conditioners, when a refrigerant leak is detected in the refrigerant circuit, the refrigerant circuit is shut off using a shutoff valve to prevent the leakage. A known conventional technology for preventing such refrigerant leakage is to store electricity in an electric double layer capacitor so that the leakage can be prevented even if a refrigerant leak occurs during a power outage, and to close the shutoff valve using the electricity stored in the electric double layer capacitor during a power outage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-46981 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned conventional technology, the first power supply circuit unit that receives power supply from an external source and generates a DC voltage, and the second power supply circuit unit for backup are each equipped with a rectifier circuit and a switching power supply (hereinafter referred to as SW power supply), which has the problem of high cost.

[0005] For example, it is possible to reduce costs by eliminating the first power supply circuit and always supplying power to the valve drive circuit via a backup board. However, in this case, the shutoff valve cannot be driven until charging of the electric double layer capacitor is complete, so if a power outage occurs immediately after power is turned on and charging is not complete, the shutoff valve cannot be operated and refrigerant leakage cannot be suppressed.

[0006] An object of the present disclosure is to provide an air conditioner that can prevent refrigerant leakage during a power outage at low cost. [Means for solving the problem]

[0007] The air conditioner of the present disclosure includes a valve drive unit that operates a valve provided in a refrigerant circuit, a control unit that controls the valve drive unit, a power supply unit that receives power from an external source to generate a DC voltage and outputs the DC voltage to a first path and a second path, and a power storage unit that receives and stores the DC voltage from the power supply unit. The first path is a path that supplies the DC voltage output from the power supply unit to the valve drive unit without passing through the power storage unit. The second path is a path that supplies the DC voltage output from the power supply unit to the valve drive unit via the power storage unit. [Effects of the Invention]

[0008] According to the present disclosure, refrigerant leakage during a power outage can be suppressed inexpensively. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing an example of the configuration of an air conditioner according to an embodiment. [Figure 2] FIG. 2 is a timing chart showing an example of operation timing of the air conditioner according to the embodiment. [Figure 3] FIG. 3 is a block diagram showing an example of the configuration of an air conditioner according to a modified example. [Figure 4] FIG. 4 is a timing chart showing an example of the operation timing of an air conditioner according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an air conditioner according to an embodiment will be described with reference to the drawings. Components having the same functions in the embodiments will be assigned the same reference numerals, and duplicated descriptions will be omitted. Note that the air conditioner described in the following embodiment is merely an example and does not limit the embodiment. Furthermore, the following embodiments may be combined as appropriate within a range that does not cause contradictions.

[0011] Fig. 1 is a block diagram showing an example of the configuration of an air conditioner according to an embodiment. As shown in Fig. 1, the air conditioner 1 has an electrical box 3 that houses electrical components that drive various parts using power from an externally supplied AC power source 2, and a refrigerant circuit 4 that circulates a refrigerant.

[0012] The electrical box 3 houses electrical components related to driving the shutoff valve 130 on the refrigerant circuit 4, including an AC / DC converter 101, a SW power supply 102, a charging circuit 103, a battery 120, a boost circuit 104, a step-down circuit 105, a shutoff valve driving circuit 106, a control circuit 107, diodes 108 and 109, and a bypass circuit 110.

[0013] The electrical box 3 also houses electrical components other than those related to driving the shutoff valve 130 (for example, electrical components that control the driving of a compressor, fan motor, etc.), but these are omitted from the illustration.

[0014] The shutoff valve 130 provided on the refrigerant circuit 4 is an electrically operated valve that shuts off the flow of refrigerant when a refrigerant leak is detected, and is, for example, an electronic expansion valve that maintains its opening when not energized. In addition to the shutoff valve 130, an evaporator, a condenser, a compressor, etc. are also provided on the refrigerant circuit 4, but these are not shown in the drawing.

[0015] The AC / DC converter 101 includes a rectifier circuit and converts an alternating current voltage (AC voltage) supplied from an AC power source 2 into a direct current voltage (DC voltage). The DC voltage converted by the AC / DC converter 101 is supplied to a SW power source 102.

[0016] The SW power supply 102 is a switching power supply that uses a switching semiconductor element. The SW power supply 102 converts the DC voltage supplied from the AC / DC converter 101 into a DC voltage of a predetermined voltage (12 [V] in the illustrated example).

[0017] A path R1 for supplying a converted DC voltage and a path R2 are connected in parallel to the SW power supply 102. The AC / DC converter 101 and the SW power supply 102 are an example of a power supply unit that receives AC power from an external source, generates a DC voltage, and outputs the DC voltage to a first path (path R1) and a second path (path R2).

[0018] Path R1 is a path that supplies the DC voltage output from the SW power supply 102 to the shutoff valve drive circuit 106 that drives the shutoff valve 130 without passing through the battery 120. In contrast, path R2 is a path that supplies the DC voltage output from the SW power supply 102 to the shutoff valve drive circuit 106 via the battery 120.

[0019] Specifically, path R1 is connected in this order from the output side of SW power supply 102, via diode 108 connected in the forward direction, to step-down circuit 105 and control circuit 107. Also, path R1 is provided with bypass circuit 110 that connects between diode 108 and step-down circuit 105 and between diode 109 and shutoff valve drive circuit 106. In path R1, this bypass circuit 110 connects shutoff valve drive circuit 106 in parallel with step-down circuit 105 and control circuit 107.

[0020] In path R2, the charging circuit 103, the battery 120, and the boost circuit 104 are connected in series in this order from the output side of the SW power supply 102. The output side of the boost circuit 104 is connected to the shutoff valve drive circuit 106 via a diode 109 connected in the forward direction. In path R2, the step-down circuit 105 and the control circuit 107 are connected in parallel to the shutoff valve drive circuit 106 by a bypass circuit 110 that connects between the diode 109 and the shutoff valve drive circuit 106 and between the diode 108 and the step-down circuit 105.

[0021] The charging circuit 103 is a circuit that supplies a DC voltage to the battery 120 based on the DC voltage (12 V) supplied from the SW power supply 102 via path R2, thereby charging the battery 120. The charging circuit 103 switches between operating and non-operating based on an ON / OFF command from the control circuit 107. When the charging circuit 103 operates, a DC current is supplied to path R2, i.e., the battery 120 side. Conversely, when the charging circuit 103 is not operating, the supply of DC current to path R2 is stopped. In this way, the charging circuit 103 switches whether to supply a DC voltage to the battery 120 side. In other words, the charging circuit 103 is an example of a switching means that is controlled by the control circuit 107 and switches so that a current for operating the shutoff valve 130 flows from the SW power supply 102 to either path R1 or path R2.

[0022] Furthermore, the charging circuit 103 detects the voltage value of the battery 120 and detects the charging state (uncharged, charging, charging completed, discharging, charge amount, etc.) of the battery 120 based on the detected voltage value. The charging circuit 103 outputs the detected charging state to the control circuit 107.

[0023] For example, the charging circuit 103 detects the charge amount of the battery 120, an uncharged state in which the voltage value of the battery 120 is less than a predetermined value corresponding to the uncharged state, and the like, by referring to table data indicating the charge amount of the battery 120 corresponding to the voltage value of the battery 120. Similarly, the charging circuit 103 detects a fully charged state in which the voltage value of the battery 120 is equal to or greater than a predetermined value corresponding to the fully charged state, by referring to the table data. Furthermore, the charging circuit 103 determines the charging state of the battery 120 as being charging when the charging circuit 103 is in a state before the fully charged state and is supplying DC voltage to the battery 120 in response to an ON command from the control circuit 107. Furthermore, the charging circuit 103 determines the charging state of the battery 120 as being discharging when the supply of DC voltage from the SW power supply 102 is interrupted due to a power outage or the like and the battery 120 is being discharged.

[0024] Battery 120 is a power storage device such as a secondary battery, which stores supplied power (DC power) and supplies (outputs) the stored power. Battery 120 is an example of a power storage unit. Battery 120 in the illustrated example outputs a DC voltage of 6.4 V. Note that a capacitor such as an electric double layer capacitor may be used as the power storage unit instead of battery 201.

[0025] The boost circuit 104 boosts the voltage output from the battery 120 to a predetermined voltage (12 V). For example, the boost circuit 104 is a boost converter of a boost chopper type. Based on an ON / OFF command from the control circuit 107, the boost circuit 104 switches whether or not to operate, i.e., whether or not to supply a boosted DC voltage.

[0026] The step-down circuit 105 steps down the DC voltage (12V-1) supplied via the diode 108 or the DC voltage (12V-2) supplied via the diode 109 and the bypass circuit 110 to a predetermined DC voltage corresponding to the control circuit 107. For example, the step-down circuit 105 is a step-down chopper type converter.

[0027] The shutoff valve drive circuit 106 is a circuit that uses a DC voltage (12V-2) supplied via a diode 109 or a DC voltage (12V-1) supplied via a diode 108 and a bypass circuit 110 as a drive source, and drives the shutoff valve 130 to open and close based on instructions from the control circuit 107. The shutoff valve drive circuit 106 is an example of a valve drive unit that operates the shutoff valve 30.

[0028] The control circuit 107 is a circuit that controls each part using the DC voltage supplied from the step-down circuit 105 as a drive source, and an MCU (Micro Controller Unit) or the like can be used. For example, the control circuit 107 outputs ON / OFF instructions to the charging circuit 103 and the boost circuit 104. The control circuit 107 also outputs an instruction to the shutoff valve drive circuit 106 to open or close the shutoff valve 130. The control circuit 107 is an example of a control part that controls the valve drive part. The control circuit 107 also receives the output of the charging circuit 103 and detects the charging state of the battery 120 (uncharged, charging, charging completed, discharging, charge amount, etc.). The control circuit 107 is an example of a detection part.

[0029] For example, if the control circuit 107 detects a refrigerant leak based on the output of a sensor or the like that detects a refrigerant leak in the refrigerant circuit 4, it instructs the shutoff valve drive circuit 106 to close the shutoff valve 130. This allows the air conditioner 1 to suppress refrigerant leakage.

[0030] Diodes 108 and 109 prevent reverse current flow in paths R1 and R2. Specifically, diode 108 prevents current (12I-2) flowing from path R2 to step-down circuit 105 via bypass circuit 110 from flowing back toward SW power supply 102. Diode 109 also prevents current (12I-1) flowing from path R2 to step-down circuit 105 via diode 108 and bypass circuit 110 from flowing back toward boost circuit 104.

[0031] Fig. 2 is a timing chart showing an example of the operation timing of the air conditioner 1 according to the embodiment. As shown in Fig. 2, the air conditioner 1 is powered on from the AC power source 2 at time t10.

[0032] When power is supplied from the AC power supply 2, a DC voltage is supplied from the AC / DC converter 101 and the SW power supply 102 to the control circuit 107 via the path R1, and the control circuit 107 is initialized.

[0033] Specifically, when power is supplied from the AC power source 2 at time t10, the control circuit 107 switches the charging circuit 103 OFF (leaving it OFF in the illustrated example) and supplies DC voltage to the shutoff valve drive circuit 106 via path R1. Then, from time t11 after time t10 (power supply ON), the control circuit 107 instructs the shutoff valve drive circuit 106 to close the shutoff valve 130 until it is fully closed. This causes the shutoff valve drive circuit 106 to perform the closing operation of the shutoff valve 130. By fully closing the shutoff valve 130, the amount of refrigerant leakage can be suppressed even if a refrigerant leak occurs before charging of the battery 120 is completed. At time t12, when the shutoff valve 130 is fully closed, the shutoff valve drive circuit 106 notifies the control circuit 107 that the instructed operation (closing operation) has been completed.

[0034] After fully closing the shutoff valve 130 in this way, the control circuit 107 sends an ON command to the charging circuit 103, causing the charging circuit 103 to operate and supply a DC voltage to the battery 120 (time t13). This starts charging the battery 120.

[0035] Next, after the charging circuit 103 detects that charging of the battery 120 is completed (time t13a), the control circuit 107 issues an ON instruction to the boost circuit 104 to operate the boost circuit 104 (time t14), thereby supplying a DC voltage from the boost circuit 104 to the subsequent stage.

[0036] Next, the control circuit 107 instructs the shutoff valve drive circuit 106 to open the shutoff valve 130 until it is fully open (time t15). As a result, the shutoff valve drive circuit 106 performs an opening operation of the shutoff valve 130. With the shutoff valve 130 fully open, the flow of refrigerant in the refrigerant circuit 4 is not interrupted, and the air conditioner 1 becomes operable. Furthermore, at time t15, the control circuit 107 notifies the charging circuit 103 of an OFF instruction to prevent the charging circuit 103 from operating. In other words, when the control circuit 107 controls the shutoff valve drive circuit 106 so that the shutoff valve drive circuit 106 operates the shutoff valve 130, it stops the output of DC voltage from the charging circuit 103 to the battery 120. As a result, the current path from the SW power supply 102 to the shutoff valve drive circuit 106 is switched to only path R1.

[0037] At time t16 when the shutoff valve 130 is fully opened, the shutoff valve drive circuit 106 notifies the control circuit 107 that the instructed operation (opening operation) has been completed. Upon receiving the notification, the control circuit 107 notifies the shutoff valve drive circuit 106 to end the valve operation (full opening), thereby controlling the shutoff valve drive circuit 106. After the opening operation, the control circuit 107 issues an ON instruction to the charging circuit 103, causing the charging circuit 103 to operate and supply a DC voltage to the battery 120 (time t16). This causes charging of the battery 120 to resume.

[0038] Furthermore, the control circuit 107 does not operate the shutoff valve 130, which has been fully closed by the shutoff valve drive circuit 106, in the direction of opening it until it detects that charging of the battery 120 is complete (time t13a). As a result, in the air conditioner 1, the shutoff valve 130 remains closed until the current supplied by the battery 120 makes it possible to close the shutoff valve 130.

[0039] Next, at time t17, the power supply from the AC power source 2 to the air conditioner 1 is cut off, resulting in a power outage. At this time, the supply of DC voltage from the SW power source 102 to the charging circuit 103 is cut off, and the supply of DC voltage from the charging circuit 103 to the battery 120 is turned off. After the power outage, DC voltage is supplied to the shutoff valve drive circuit 106 and the control circuit 107 from the battery 120.

[0040] When the control circuit 107 detects a state in which the supply of DC voltage from the SW power supply 102 is cut off and DC voltage is being supplied from the battery 120, that is, when it detects a power outage, it instructs the shutoff valve drive circuit 106 to close the shutoff valve 130 until it is fully closed. Based on the instruction from 107, the shutoff valve drive circuit 106 performs the closing operation of the shutoff valve 130 (shuts off the refrigerant). By fully closing the shutoff valve 130, the amount of refrigerant leakage can be suppressed even if a refrigerant leak occurs during a power outage.

[0041] When the shutoff valve 130 is closed by the DC voltage supplied from the battery 120, the charge level of the battery 120 decreases, and the state of the battery 120 changes from a fully charged state to a state of charge level between not fully charged and fully charged (time t17a). This state is equivalent to the charging state when there is no power outage, and is therefore represented as charging in the illustrated example.

[0042] At time t18 when the shutoff valve 130 is fully closed, the shutoff valve drive circuit 106 notifies the control circuit 107 that the instruction operation (closing operation) has been completed. After the shutoff valve 130 is fully closed in this manner, the control circuit 107 notifies the boost circuit 104 of an OFF instruction, and stops the supply of DC voltage from the boost circuit 104 (time t18). As a result, in the air conditioner 1, after the refrigerant is cut off by the shutoff valve 130, the supply of DC voltage is stopped, and it is possible to prevent unnecessary consumption of the battery 120.

[0043] (Variation) Fig. 3 is a block diagram showing an example of the configuration of an air conditioner according to a modified example. As shown in Fig. 3, air conditioner 1a differs from air conditioner 1 in that, instead of the bypass circuit 110 described above, air conditioner 1a has a bypass circuit 110a including a diode 109 and a bypass circuit 110b including a bypass relay 111.

[0044] Specifically, bypass circuits 110a and 110b connect between the boost circuit 104 and the shutoff valve drive circuit 106 and between the diode 108 and the step-down circuit 105. A diode 109 is connected in the forward direction to bypass circuit 110a from between the boost circuit 104 and the shutoff valve drive circuit 106 to between the diode 108 and the step-down circuit 105. Therefore, the DC voltage in path R1 is supplied to the shutoff valve drive circuit 106 via bypass circuit 110b.

[0045] The bypass circuit 110b is provided with a bypass relay 111 that performs a switching operation (supply / cut-off of DC voltage) based on an ON / OFF command from the control circuit 107. That is, the bypass relay 111 is an example of a cut-off means that is controlled by the control circuit 107 and cuts off the supply of DC voltage from the SW power supply 102 to the shut-off valve drive circuit 106. The bypass relay 111 is also an example of a switching means that is controlled by the control circuit 107 and switches so that a current for operating the shut-off valve 130 flows from the SW power supply 102 to either path R1 or path R2.

[0046] Fig. 4 is a timing chart showing an example of the operation timing of the air conditioner 1a according to the modified example. As shown in Fig. 4, the air conditioner 1a is powered on from the AC power source 2 at time t20.

[0047] When power is supplied from the AC power supply 2, a DC voltage is supplied from the AC / DC converter 101 and the SW power supply 102 to the control circuit 107 via the path R1, and the control circuit 107 is initialized.

[0048] Specifically, from time t21 after time t20 (power-on), the control circuit 107 issues an ON command to the bypass relay 111 while keeping the charging circuit 103 OFF, causing a DC voltage to be supplied to the shutoff valve drive circuit 106 via the bypass circuit 110b. As a result, the current path from the SW power supply 102 to the shutoff valve drive circuit 106 is switched to path R1. The control circuit 107 also commands the shutoff valve drive circuit 106 to close the shutoff valve 130. As a result, the shutoff valve drive circuit 106 performs an operation to close the shutoff valve 130.

[0049] At time t22 when the shutoff valve 130 is fully closed, the shutoff valve drive circuit 106 notifies the control circuit 107 that the instructed operation (closing operation) has been completed. In response to this notification, the control circuit 107 issues an OFF instruction to the bypass relay 111, and cuts off the supply of DC voltage to the shutoff valve drive circuit 106 via the bypass circuit 110b. As a result, the current path from the SW power supply 102 to the shutoff valve drive circuit 106 is switched to path R2.

[0050] Next, at time t23 after time t22, the control circuit 107 sends an ON instruction to the charging circuit 103, causing the charging circuit 103 to operate and supply a DC voltage to the battery 120. As a result, charging of the battery 120 begins.

[0051] Next, after the charging circuit 103 detects that charging of the battery 120 is completed (time t24), the control circuit 107 issues an ON instruction to the boost circuit 104 to operate the boost circuit 104 (time t25), thereby supplying a DC voltage from the boost circuit 104 to the subsequent stage.

[0052] Next, the control circuit 107 instructs the shutoff valve drive circuit 106 to open the shutoff valve 130 until it is fully open (times t26 to t27). The shutoff valve drive circuit 106 checks the opening operation of the shutoff valve 130. At this time, the supply of DC voltage to the shutoff valve drive circuit 106 via the bypass circuit 110b remains cut off, and the current path from the SW power supply 102 to the shutoff valve drive circuit 106 remains path R2. In other words, in the air conditioner 1a, after the charging state has reached charging completion, there is no need to switch between paths R1 and R2 each time the shutoff valve 130 is operated.

[0053] Furthermore, the control circuit 107 does not operate the shutoff valve 130, which has been fully closed by the shutoff valve drive circuit 106, in the direction of opening it until it detects that charging of the battery 120 is complete (time t24). As a result, in the air conditioner 1a, the shutoff valve 130 remains closed until the current supplied by the battery 120 makes it possible to close the shutoff valve 130.

[0054] Next, at time t28, the power supply from the AC power source 2 to the air conditioner 1 is cut off, resulting in a power outage. At this time, the supply of DC voltage from the SW power source 102 to the charging circuit 103 is cut off, the supply of DC voltage from the charging circuit 103 to the battery 120 is turned off, and the battery 120 begins to discharge. After the power outage, DC voltage is supplied to the shutoff valve drive circuit 106 and the control circuit 107 due to the discharge of the battery 120.

[0055] When the control circuit 107 detects a state in which the battery 120 is discharging while the supply of DC voltage from the SW power supply 102 is cut off, that is, when it detects a power outage, it instructs the shutoff valve drive circuit 106 to close the shutoff valve 130. Based on the instruction from 107, the shutoff valve drive circuit 106 performs a closing operation of the shutoff valve 130 (shutoff of the refrigerant).

[0056] When the shutoff valve 130 is closed by the DC voltage supplied from the battery 120, the charge level of the battery 120 decreases, and the state of the battery 120 changes from a fully charged state to a state of charge level between not fully charged and fully charged (time t29). This state is equivalent to the charging state when there is no power outage, and is therefore represented as charging in the illustrated example.

[0057] At time t30 when the shutoff valve 130 is fully closed, the shutoff valve drive circuit 106 notifies the control circuit 107 that the instructed operation (closing operation) has been completed. After the shutoff valve 130 is fully closed in this manner, the control circuit 107 notifies the charging circuit 103 and the boost circuit 104 of an OFF instruction, and stops the supply of DC voltage from the boost circuit 104.

[0058] As described above, the air conditioner 1, 1a has a valve drive unit (shutoff valve drive circuit 106), a control unit (control circuit 107), a power supply unit (AC / DC converter 101, SW power supply 102), and a power storage unit (battery 120). The valve drive unit operates a valve (shutoff valve 130) provided on the refrigerant circuit 4. The control unit controls the valve drive unit. The power supply unit receives power from an external source to generate a DC voltage and outputs the DC voltage to a first path (path R1) and a second path (path R2). The power storage unit receives and stores the DC voltage from the power supply unit. The first path is a path that supplies the DC voltage output from the power supply unit to the valve drive unit without passing through the power storage unit. The second path is a path that supplies the DC voltage output from the power supply unit to the valve drive unit via the power storage unit.

[0059] As a result, the air conditioners 1, 1a can share a power supply unit for the first and second paths, eliminating the need to provide a power supply unit for each path and making it possible to inexpensively prevent refrigerant leakage during a power outage.

[0060] Furthermore, in the air conditioners 1 and 1a, when the valve drive unit operates the valve, current for operating the valve flows from the power supply unit to either the first path or the second path. For example, in the air conditioner 1, when the valve is closed (times t11 to t12) after power is turned on from the AC power supply 2 (time t10), the charging circuit 103 is inactive (OFF), so no current flows through path R2, but current for operating the valve flows through path R1. Furthermore, in the air conditioner 1, when the valve is fully open (times t15 to t16), the charging circuit 103 is inactive (OFF), so no current flows through path R2, but current for operating the valve flows through path R1. Furthermore, in the air conditioner 1a, when the valve is closed (times t21 to t22) after power is supplied from the AC power source 2 (time t20), the charging circuit 103 is inactive (OFF) and the bypass relay 111 is ON, and current for operating the valve flows along path R1 rather than path R2. Similarly, in the air conditioner 1a, when the valve is fully open (times t26 to t27), the charging circuit 103 is active (ON) and the bypass relay 111 is OFF, and current for operating the valve flows along path R2 rather than path R1.

[0061] As a result, in the air conditioners 1 and 1a, when the valve drive unit operates the valve, current flows from the power supply unit to only one of the first path or the second path (current does not flow from the power supply unit to both the first path and the second path), so the current flowing to the power supply unit can be suppressed. Therefore, in the air conditioners 1 and 1a, a smaller power supply unit can be provided than in the case where current flows to both the first path and the second path, and refrigerant leakage can be suppressed with an inexpensive configuration.

[0062] In addition, a charging circuit 103 controlled by the control unit and a power storage unit are connected in series to the second path of the air conditioner 1, 1a, with the charging circuit 103 and the power storage unit next. When the control unit of the air conditioner 1 controls the valve drive unit so that the valve drive unit operates the valve, the control unit stops the output of DC voltage from the charging circuit to the power storage unit.

[0063] As a result, in the air conditioner 1, 1a, when the valve drive unit operates the valve, it is possible to make the air flow through the first path rather than through the second path.

[0064] Furthermore, the first path of the air conditioner 1a is controlled by the control unit and has a cutoff means (bypass relay 111) that cuts off the supply of DC voltage from the power supply unit to the valve drive unit. In the second path of the air conditioner 1a, a charging circuit 103 and a power storage unit, both controlled by the control unit, are connected in series, with the charging circuit 103 followed by the power storage unit. When the control unit of the air conditioner 1a controls the valve drive unit so that the valve drive unit operates the valve, the control unit controls the cutoff means to cut off the supply of DC voltage in the first path, or stops the output of DC voltage from the charging circuit 103 to the power storage unit.

[0065] As a result, in the air conditioner 1a, when the valve drive unit operates the valve, it is possible to ensure that current flows only through either the first path or the second path.

[0066] The air conditioner 1a also has switching means (charging circuit 103, bypass relay 111) that is controlled by the control unit and switches the flow of current for operating the valve from the power supply unit to either the first path or the second path, and a detection unit (control circuit 107) that detects the charge state of the storage unit. When the control unit controls the valve drive unit to operate the valve, it controls the switching means so that current flows from the power supply unit to either the first path or the second path based on the charge state.

[0067] As a result, in the air conditioner 1a, when the valve drive unit operates the valve, it is possible to ensure that current flows through only one of the first path and the second path, depending on the state of charge of the power storage unit.

[0068] Specifically, when the control unit of air conditioner 1a controls the valve drive unit to operate the valve, if the charging state is "charging" (charging continues to the power storage unit), the control unit controls the switching means so that current flows from the power supply unit to the first path. When the charging state is "charging complete" (charging complete) (charging to the power storage unit is complete), the control unit of air conditioner 1a controls the switching means so that current flows from the power supply unit to the second path. For example, in air conditioner 1a, when the valve drive unit controls the valve drive unit to operate the valve, if the charging state is "charging" (t21 to t22), the charging circuit 103 is inactive (OFF) and the bypass relay 111 is ON, so that current for operating the valve flows along path R1 rather than path R2. On the other hand, when the valve driving unit controls the valve driving unit to operate the valve, if the charging state is complete (t26 to t27), the charging circuit 103 is operated (ON), the bypass relay 111 is turned OFF, and the current for operating the valve flows to the path R2 side instead of the path R1 side.

[0069] As a result, in the air conditioner 1a, when the valve drive unit operates the valve, if the charging state is "charging," in which charging of the power storage unit is continuing, current can flow through the first path. Furthermore, in the air conditioner 1, 1a, when the valve drive unit operates the valve, if the charging state is "charging complete," in which charging of the power storage unit is complete, current can flow through the second path. Therefore, for example, after charging of the power storage unit is complete, the valve can be driven by current supplied from the second path, eliminating the need to switch between the first and second paths each time the valve is operated. For example, the control circuit 107 of the air conditioner 1, 1a may periodically operate the shutoff valve 130 (by operating it a predetermined amount in the closing direction, then operating it a predetermined amount in the opening direction, and then returning it to its original position) to prevent the shutoff valve 130 from sticking due to prolonged inactivity. When the shutoff valve 130 is periodically operated in this manner, the air conditioner 1, 1a does not need to switch between the first and second paths each time it operates.

[0070] The air conditioners 1 and 1a also have switching means (charging circuit 103, bypass relay 111) that is controlled by the control unit and switches the flow of current for operating the valve from the power supply unit to either the first path or the second path. When the power supply unit receives power from an external source, the control unit of the air conditioners 1 and 1a controls the switching means so that current flows from the power supply unit to the first path, and controls the valve drive unit so that the valve is fully closed.

[0071] As a result, when the power supply unit of the air conditioner 1 or 1a receives power from an external source, the current is switched to flow through the first path, and the valve is fully closed, thereby preventing refrigerant leakage even if a power outage occurs shortly after power is turned on.

[0072] Furthermore, a charging circuit 103 controlled by the control unit and a power storage unit are connected in series to the second path of the air conditioner 1, 1a, with the charging circuit and the power storage unit being connected in that order. The control unit of the air conditioner 1, 1a controls the valve drive unit to fully close the valve, and then controls the valve drive unit to end the valve operation, and after the valve operation has ended, operates the charging circuit 103 to start charging the power storage unit.

[0073] As a result, in the air conditioner 1, 1a, charging of the storage unit begins after the valve operation has finished, so that when the valve drive unit operates the valve, current flows only through either the first path or the second path.

[0074] Furthermore, the control unit of the air conditioner 1, 1a does not operate the valve drive unit in the direction of opening the valve that is fully closed until charging of the power storage unit is complete.

[0075] This allows the air conditioner 1, 1a to keep the valve closed until charging of the storage unit is complete, i.e., until the valve can be closed using the current supplied by the storage unit, thereby more reliably suppressing refrigerant leakage. [Explanation of symbols]

[0076] 1, 1a...Air conditioner 2…AC power supply 3...Electrical box 4...Refrigerant circuit 101...AC / DC 102…SW power supply 103…Charging circuit 104...Boost circuit 105...Step-down circuit 106...Shut-off valve drive circuit 107...Control circuit 108, 109...Diodes 110, 110a, 110b...bypass circuits 111...Bypass relay 120...battery 130...Shut-off valve R1, R2... Route t10~t30…Time

Claims

1. a valve driving unit that operates a valve provided in the refrigerant circuit; a control unit that controls the valve driving unit; a power supply unit that receives power from an external source, generates a DC voltage, and outputs the DC voltage to the first path and the second path; a power storage unit that receives a DC voltage from the power supply unit and stores the DC voltage, the first path is a path for supplying the DC voltage output from the power supply unit to the valve drive unit without passing through the power storage unit, the second path is a path for supplying the DC voltage output from the power supply unit to the valve drive unit via the power storage unit, the control unit controls the power supply unit to operate the valve, and the power supply unit and the charging circuit are connected in series to the second path, and the control unit controls the power supply unit to operate the valve, and the power supply unit and the charging circuit are connected in series to the second path, and the control unit controls the power supply unit to operate the valve, and the power supply unit and the charging circuit are connected in series to the second path, and the power supply unit and the charging circuit are connected in series to operate the valve ... and the power supply unit are connected in series to operate the valve, and the power supply unit and the charging circuit and the power supply unit are connected in series to operate the valve, and the power supply unit and the charging circuit and the control unit controls the switching means so that the current flows from the power supply unit to the first path when the power supply unit receives power supply from an external source, and controls the valve drive unit so as to fully close the valve, and after the operation of the valve is completed, controls the charging circuit to start charging the power storage unit, and after controlling the valve to be fully closed, controls the switching means so that the current flows from the power supply unit to the second path when the valve drive unit operates the valve. An air conditioner characterized by the above.

2. the control unit does not operate the valve drive unit in a direction to open the valve that is fully closed until charging of the power storage unit is completed.

2. The air conditioner according to claim 1.

3. A boost circuit that boosts the voltage of the power storage unit controlled by the control unit included in the second path to a predetermined voltage and supplies the voltage to the valve drive unit; a detection unit that detects a charging state of the power storage unit; and the control unit controls the boost circuit to output the boosted voltage after charging of the power storage unit is completed.

2. The air conditioner according to claim 1.

4. The power supply further includes a boost circuit that boosts the voltage of the power storage unit controlled by the control unit included in the second path to a predetermined voltage and supplies the voltage to the valve drive unit; the control unit controls the valve drive unit to fully close the valve when the external power supply is interrupted, and after the valve drive unit fully closes the valve, controls the boost circuit to stop the supply of the boosted voltage.

2. The air conditioner according to claim 1.

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