air conditioner

Abstract

To reliably 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 storage section which stores electric power, a charging section which controls charging to the power storage section, and a boost section which boosts voltage from the power storage section and outputs the boosted voltage to the valve driving section. The air conditioner includes a first substrate on which the valve driving section, the control section, the charging section, and the boost section are mounted, and a second substrate which is connected to the first substrate through a connector and on which the power storage section is mounted.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, power storage devices such as capacitors and batteries deteriorate over time, reducing their storage capacity. Furthermore, deterioration is accelerated by heat generated by surrounding electrical components. Therefore, in order to prevent refrigerant leakage during a power outage, it is necessary to replace the power storage device at the appropriate time. This power storage device is fixed by soldering or other means to a circuit board on which a circuit for driving a shutoff valve is mounted. Therefore, replacing the power storage device requires removing the soldering or replacing the entire board. Therefore, replacing the power storage device is not easy. If the power storage device is not replaced appropriately, there is a risk that refrigerant leakage during a power outage will not be prevented.

[0005] The present disclosure proposes an air conditioner that can suppress refrigerant leakage during a power outage. [Means for solving the problem]

[0006] The air conditioner of the present disclosure has a valve drive unit that operates a valve provided in a refrigerant circuit, a control unit that controls the valve drive unit, a power storage unit that stores electric power, a charging unit that controls charging to the power storage unit, and a boost unit that boosts the voltage from the power storage unit and outputs it to the valve drive unit.The air conditioner includes a first board on which the valve drive unit, control unit, charging unit, and boost unit are mounted, and a second board connected to the first board via a connector and on which the power storage unit is mounted. [Effects of the Invention]

[0007] According to the present disclosure, refrigerant leakage can be suppressed during a power outage. [Brief explanation of the drawings]

[0008] [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 an explanatory diagram showing an example of mounting a board in an electrical box. [Figure 3] FIG. 3 is an explanatory diagram illustrating an example of the operation of the air conditioner according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] 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.

[0010] 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.

[0011] The electrical box 3 houses electrical components related to driving the shutoff valve 30 on the refrigerant circuit 4, including an AC / DC converter 101, a SW power supply 102, a charging circuit 103, a battery 201, 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.

[0012] The electrical box 3 also houses electrical components other than those related to driving the shutoff valve 30 (for example, electrical components that control the driving of a compressor, fan motor, etc.), but these are omitted from the illustration.

[0013] The shutoff valve 30 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 30, an evaporator, a condenser, a compressor, etc. are also provided on the refrigerant circuit 4, but these are not shown in the figure.

[0014] The AC / DC converter 101 includes a rectifier circuit and converts an alternating current voltage (AC voltage) supplied from the AC power supply 2 into a direct current voltage (DC voltage). The DC voltage converted by the AC / DC converter 101 is supplied to the SW power supply 102.

[0015] 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). The SW power supply 102 supplies the converted DC voltage to a charging circuit 103 and to a step-down circuit 105 and a shutoff valve drive circuit 106 via a diode 108.

[0016] The charging circuit 103 is a circuit that supplies a DC voltage to the battery 201 based on the DC voltage (12 [V]) supplied from the SW power supply 102, and charges the battery 201. The charging circuit 103 controls the operation and non-operation of the charging circuit 103, i.e., the start and stop of charging the battery 201, based on the ON / OFF command of the control circuit 107. The charging circuit 103 is an example of a charging unit.

[0017] Furthermore, the charging circuit 103 monitors the charging voltage of the battery 201 and detects the charging state (uncharged, charging, charging completed, charged amount, etc.) of the battery 201 based on the charging voltage. The charging circuit 103 outputs the detected charging state to the control circuit 107.

[0018] For example, the charging circuit 103 detects the charge amount of the battery 201, an uncharged state in which the voltage value of the battery 201 is less than a predetermined value corresponding to the uncharged state, etc., by referring to table data indicating the charge amount of the battery 201 corresponding to the voltage value of the battery 201.

[0019] Similarly, by referring to the table data, the charging circuit 103 detects the charging completion state in which the voltage value of the battery 201 is equal to or greater than a predetermined value corresponding to the charging completion state.

[0020] Furthermore, when the charging circuit 103 is in a state before reaching the above-mentioned charging completion state and is supplying a DC voltage to the battery 201 in response to an ON instruction from the control circuit 107, the charging state of the battery 201 is set to charging.

[0021] Furthermore, on the output side of charging circuit 103 to battery 201, power storage element 103a is connected in parallel to battery 201 (see FIG. 3).

[0022] The storage element 103a is a capacitor or the like having a capacity smaller than that of the battery 201. Specifically, the capacity of the storage element 103a is 10 times that of the battery 201. -5 It is sufficiently small, less than double the size.

[0023] Here, the capacity is, for example, electrostatic capacitance. The electrostatic capacity of the battery 201 can be calculated from the electric capacity discharged from the fully charged battery 201 (the amount of charge after charging is completed) using the following formula (1). Equation (1): Capacitance (F) = Discharge capacity (Ah) / Voltage (V) × 3600

[0024] For example, the capacitance of the storage element 103a is about 100 [uF], whereas the capacitance of the battery 201 obtained by the above formula (1) is 82 [F].

[0025] In the air conditioner 1, such a storage element 103a is connected in parallel with the battery 201. For this reason, in the air conditioner 1, when the board 20 is not connected, i.e., when the battery 201 with a large capacitance is not present, the output voltage of the charging circuit 103 reaches a predetermined voltage value or higher in a shorter time than when the battery 201 is present. For example, when the capacitance of the storage element 103a is 10 times larger than the capacitance of the battery 201, -5 If the time is less than twice the predetermined time, the output voltage of the charging circuit 103 will reach or exceed the predetermined voltage value in units of seconds.

[0026] Battery 201 is a power storage device such as a secondary battery, which stores supplied power (DC power) and supplies (outputs) the stored power. Battery 201 is an example of a power storage unit. Battery 201 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. In this case, a capacitor with a smaller capacitance than that of the electric double layer capacitor is used as power storage element 103a.

[0027] The boost circuit 104 boosts the voltage (6.4 [V]) output from the battery 201 to a predetermined voltage (12 [V]) and outputs it to the shutoff valve drive circuit 106. For example, the boost circuit 104 is a boost converter of a boost chopper type. The boost circuit 104 is an example of a boost unit. Based on an ON / OFF command from the control circuit 107, the boost circuit 104 switches whether or not to operate the boost circuit 104, i.e., whether or not to supply a boosted DC voltage.

[0028] 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.

[0029] 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 30 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.

[0030] 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 for example, an MCU (Micro Controller Unit) or the like can be applied. The control circuit 107 has a control unit 107b that controls each part by reading and executing programs stored in an internal memory (see FIG. 2). 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 instructions to the shutoff valve drive circuit 106 to open or close the shutoff valve 30.

[0031] 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 30. This allows the air conditioner 1 to suppress refrigerant leakage.

[0032] The control circuit 107 also has a power outage detection unit (not shown) that detects when the AC power source 2 experiences a power outage and the power supply to the charging circuit 103 is cut off. When the power outage detection unit detects a power outage of the AC power source 2, the control circuit 107 instructs the shutoff valve drive circuit 106, which, like the control circuit 107, is driven by power from the battery 201, to close the shutoff valve 30. This allows the air conditioner 1 to reliably suppress refrigerant leakage during a power outage.

[0033] Diode 108 is connected in the forward direction from SW power supply 102 toward step-down circuit 105 and prevents reverse current flow. Diode 109 is connected in the forward direction from boost circuit 104 toward bypass circuit 110 and prevents reverse current flow. Specifically, diode 108 prevents reverse current (12I-2) flowing toward SW power supply 102 via bypass circuit 110. Diode 109 also prevents reverse current (12I-1) flowing toward boost circuit 104 via bypass circuit 110.

[0034] The bypass circuit 110 has one end connected between the diode 108 and the step-down circuit 105 and the other end connected between the diode 109 and the shutoff valve drive circuit 106, and is a circuit that bypasses both ends.

[0035] Of the electrical components in the electrical box 3 described above, the AC / DC converter 101, SW power supply 102, charging circuit 103, boost circuit 104, step-down circuit 105, shutoff valve drive circuit 106, control circuit 107, diode 108, diode 109, and bypass circuit 110 are mounted on a board 10. A battery 201 is mounted on a board 20 that is independent from the board 10. The board 10 is an example of a first board, and the board 20 is an example of a second board.

[0036] 2 is an explanatory diagram showing an example of mounting the boards 10 and 20 inside the electrical box 3. As shown in FIG. 2, the terminal 120 is a power terminal connected to the AC power source 2. The board 10 is connected to the AC power source 2 via the terminal 120, and an alternating current voltage (AC voltage) supplied from the AC power source 2 is supplied to the AC / DC converter 101.

[0037] The board 10 is provided with a connector 121 for connection to the board 20 via wiring 130 such as a wire harness, and a terminal 122 for connection to an external device such as the shutoff valve 30.

[0038] The connector 121 is a component that connects the wiring 130 to the wiring on the substrate 10. The connector 121 is configured, for example, so that a socket is inserted into a plug, and the electrical connection and disconnection between the substrate 10 and the wiring 130 can be easily performed by inserting and removing the plug.

[0039] The control circuit 107 has a charging voltage detection circuit 107a and a control unit 107b. The charging voltage detection circuit 107a detects the output voltage that the charging circuit 103 outputs to the connector 121. In other words, the charging voltage detection circuit 107a is an example of a voltage detection unit.

[0040] The control unit 107b detects whether or not the board 20 is connected based on the output voltage detected by the charging voltage detection circuit 107a. Specifically, the control unit 107b monitors the output voltage detected by the charging voltage detection circuit 107a after the charging circuit 103 starts charging the battery 201 when the AC power source 2 is turned on. The control unit 107b then measures the time it takes for the output voltage to reach or exceed a predetermined voltage value set in advance in a memory or the like, and detects whether or not the board 20 is connected based on the measured time.

[0041] For example, when the board 20 is not connected, the output voltage detected by the charging voltage detection circuit 107a becomes equal to or greater than a predetermined voltage value in a relatively short time due to the storage element 103a connected to the output side of the charging circuit 103. Therefore, the control unit 107b detects that the board 20 is not connected when the measured time is less than a predetermined time (for example, 5 seconds).

[0042] For example, as described above, the capacitance calculated from the discharge capacity of battery 201 is 82 [F], and the capacitance of power storage element 103a is 100 [uF]. -5The capacitance of the storage element 103a is sufficiently small compared to the capacitance of the battery 201, so that the time it takes for the output voltage of the charging circuit 103 to reach or exceed the predetermined voltage value can be sufficiently different depending on whether the substrate 20 is connected or not, thereby enabling accurate detection of whether the substrate 20 is connected or not. Furthermore, because the capacitance of the storage element 103a is sufficiently small compared to the capacitance of the battery 201, the time it takes for the output voltage of the charging circuit 103 to reach or exceed the predetermined voltage value can be sufficiently different depending on whether the substrate 20 is connected or not, allowing accurate detection of whether the substrate 20 is connected or not. Furthermore, because the capacitance of the storage element 103a is sufficiently small, the time it takes for the output voltage of the charging circuit 103 to reach or exceed the predetermined voltage value can be quickly detected. Furthermore, because the storage element 103a is connected to the output side of the charging circuit 103, noise in the output voltage detected by the charging voltage detection circuit 107a can be suppressed even when the substrate 20 is not connected. Therefore, the control unit 107b can accurately measure the time it takes for the output voltage to reach or exceed a predetermined voltage value, and can accurately detect whether the board 20 is connected or not.

[0043] Note that the method for detecting whether or not the board 20 is connected is not limited to this. For example, whether or not the board 20 is connected may be detected based on the output voltage at the time when a predetermined waiting time has elapsed since the charging circuit 103 started charging the battery 201. In this case, if the output voltage is equal to or greater than a predetermined threshold value set in advance in a memory or the like, it can be detected that the board 20 is not connected.

[0044] The control circuit 107 notifies the detected presence or absence of connection of the board 20 by the presence or absence of light emission from an LED (Light Emitting Diode), the presence or absence of a buzzer sound from a buzzer device, etc. This allows the user to easily know the presence or absence of connection of the board 20.

[0045] The substrate 20 has a connector 202 for connecting to the substrate 10 via the wiring 130. The connector 202 is a component that connects the wiring 130 to the battery 201 on the substrate 20. The connector 202 is configured, for example, so that a socket is inserted into a plug, and is configured so that the substrate 20 and the wiring 130 can be easily electrically connected and disconnected by inserting and removing the plug.

[0046] In the air conditioner 1, by removing one of the connectors 121, 202 that connect to the wiring 130, the board 20 can be separated from the board 10 and removed from the electrical box 3. Furthermore, in the air conditioner 1, by connecting the wiring 130 to the connectors 121, 202, the boards 10 and 20 can be connected and the board 20 can be attached. In this way, in the air conditioner 1, the boards 10 and 20 are connected via the connectors 121, 202, so that the work of replacing the board 20 can be easily performed.

[0047] Fig. 3 is an explanatory diagram illustrating an example of the operation of the air conditioner 1 according to the embodiment. Fig. 3 illustrates an example of the operation of detecting whether or not the board 20 is connected during a factory inspection.

[0048] During factory inspection, after power supply from an external power source starts, when control unit 107b issues a charge instruction (ON instruction) to charging circuit 103 (S20), charging circuit 103 starts charging battery 201 (S21).

[0049] Here, charging voltage detection circuit 107a detects the output voltage that charging circuit 103 outputs to connector 121, and outputs the detected output voltage to control unit 107b. Control unit 107b monitors the output voltage that control unit 107b outputs (S23).

[0050] Next, the control unit 107b measures the time (charging time) until the output voltage reaches or exceeds a predetermined voltage value previously set in a memory or the like, and determines (detects) whether or not the board 20 is connected based on the measured charging time. Specifically, the control unit 107b detects that the board 20 is not connected if the charging time is less than the predetermined time.

[0051] Based on the detection result of the control unit 107b, for example, if the board 20 is not connected, the control circuit 107 issues a notification by illuminating an LED, emitting a buzzer sound, etc. This allows the user (inspector) to easily know that the board 20 is not connected during the factory inspection (S2).

[0052] As described above, the air conditioner 1 has a valve drive unit (shutoff valve drive circuit 106), a control unit (control circuit 107), a power storage unit (battery 201), a charging unit (charging circuit 103), and a boost unit (boost circuit 104). The valve drive unit operates a valve (shutoff valve 30) provided on the refrigerant circuit 4. The control unit controls the valve drive unit. The power storage unit stores electric power. The charging unit controls charging to the power storage unit. The boost unit boosts the voltage from the power storage unit and outputs it to the valve drive unit. The air conditioner 1 has a first board (board 10) on which the valve drive unit, control unit, charging unit, and boost unit are mounted, and a second board (board 20) connected to the first board via a connector and on which the power storage unit is mounted.

[0053] In this way, in the air conditioner 1, the power storage unit is mounted on a second board that is independent of the first board on which the charging unit connected before the power storage unit and the boost unit connected after the power storage unit are mounted so as to be connected via a connector, thereby suppressing deterioration of the power storage unit due to heat generated by the charging unit and boost unit. As a result, in the air conditioner 1, power for the power storage unit can be secured more reliably, and the shutoff valve 30 can be operated (closed) more reliably in the event of a power outage.

[0054] Furthermore, in the air conditioner 1, the second board is connected to the first board via a connector, so when replacing the power storage unit due to deterioration over time, the second board with the old power storage unit mounted thereon can be removed from the connector and a second board with a new power storage unit mounted thereon can be connected to the connector. Therefore, in the air conditioner 1, the power storage unit can be easily replaced without the need for the complicated task of removing the power storage unit soldered to the board.

[0055] The air conditioner 1 also has a voltage detection unit (control unit 107b) that detects the output voltage of the charging unit. The control unit of the air conditioner 1 detects whether the second board is connected or not based on the detected output voltage. This allows the air conditioner 1 to easily detect that the second board is not connected, and based on this detection result, it is possible to avoid a state in which the power storage unit is not connected.

[0056] Furthermore, the charging unit of the air conditioner 1 starts charging the power storage unit after the start of power supply from the external power source. The control unit of the air conditioner 1 measures the time from when the charging unit starts charging until the output voltage reaches or exceeds a predetermined voltage value, and detects whether or not the second board is connected based on the measured time. This allows the air conditioner 1 to more reliably detect whether or not the second board is connected based on the time it takes for the output voltage of the charging unit to reach or exceed the predetermined voltage value.

[0057] The charging unit of the air conditioner 1 also has a storage element 103a connected in parallel to the output to the storage unit and having a capacity smaller than that of the storage unit. This allows the air conditioner 1 to detect that the second board is not connected if it takes a short time for the output voltage of the charging unit to reach or exceed a predetermined voltage value. [Explanation of symbols]

[0058] 1...Air conditioner 2…AC power supply 3...Electrical box 4...Refrigerant circuit 10...Substrate 20...Substrate 30...Shut-off valve 101...AC / DC converter 102...SW power supply 103…Charging circuit 103a...electricity storage element 104...Boost circuit 105...Step-down circuit 106...Shut-off valve drive circuit 107...Control circuit 107a...Charging voltage detection circuit 107b...Control unit 108, 109...Diodes 110...Bypass circuit 120, 122...Terminal 121, 202...Connectors 130...Wiring 201...Battery

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 storage unit that stores power; a charging unit that controls charging of the power storage unit; a boost unit that boosts the voltage from the power storage unit and outputs the boosted voltage to a valve drive unit; a storage element having a capacity smaller than that of the storage unit, the storage element being connected in parallel with the storage unit; a voltage detection unit that detects an output voltage of the charging unit, a first substrate on which the valve driving unit, the control unit, the charging unit, the boost unit, the power storage element, and the voltage detection unit are mounted; a second substrate connected to the first substrate via a connector and on which the power storage unit is mounted; Equipped with The control unit detects whether the second board is connected or not based on the detected change in the output voltage when the charging unit charges the power storage unit. An air conditioner characterized by the above.

2. the charging unit starts charging the power storage unit after power supply from an external power source starts, the control unit measures the time from when the charging unit starts charging until the output voltage becomes equal to or greater than a predetermined voltage value, and detects whether the second board is connected based on the measured time.

2. The air conditioner according to claim 1.

3. The charging unit starts charging the storage unit after power supply from an external power source starts, the control unit detects whether the second board is connected or not based on the output voltage after a predetermined period has elapsed since the charging unit started charging.

2. The air conditioner according to claim 1.

4. The capacity of the storage element is 10 times the capacity of the storage unit. －５ is less than double, 2. The air conditioner according to claim 1.

5. The power storage unit is configured by either a secondary battery or an electric double layer capacitor, The storage element is constituted by a capacitor.

5. The air conditioner according to claim 4.

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