air conditioning unit

Abstract

In the air conditioning unit (101), the indoor unit (2) and the outdoor unit (3) are connected by three core wires: a power line (4), a common line (5), and a signal line (6). Commercial power is supplied through the power line and the common line. The indoor unit has a first switch (7) that opens and closes the connection between the power line and the signal line. The outdoor unit has a second switch (9) that opens and closes the connection between the power line and the outdoor unit, an outdoor rectifier (10), an outdoor smoothing section (11), and a third switch (12) that connects the signal line and the resistor connected to the downstream of the second switch in the off state and becomes an open circuit in the on state. When the outdoor unit is started from the standby state, the first switch is turned on when the third switch is off, thereby allowing the surge current to flow through the indoor unit to the outdoor smoothing section to charge the outdoor smoothing section. After charging, the second switch is turned on, and then the first switch is turned off and the third switch is turned on.

Description

Technical Field

[0001] This disclosure relates to an air conditioning unit having an indoor unit and an outdoor unit. Background Technology

[0002] In the past, in order to reduce standby power consumption, there was an air conditioning unit that connected the outdoor unit and the indoor unit with a power wiring for transmitting AC power from an AC power source, a signal line for transmitting signals, and a common line shared by the transmission of AC power and the transmission of signals.

[0003] The indoor unit of the air conditioning unit described in Patent Document 1 includes an indoor control circuit and a first switch. This first switch, controlled by the indoor control circuit, switches between an on / off state (connecting a signal line to a power line) and a disconnected state (not connected). Furthermore, the outdoor unit of the air conditioning unit described in Patent Document 1 includes an outdoor control circuit and a second switch. The outdoor control circuit includes a main relay. The second switch, controlled by the outdoor control circuit, switches between an on / off state (connecting the outdoor control circuit to an AC power source) and a off / off state (connecting it to a signal line). Moreover, the indoor and outdoor control circuits activate the outdoor control circuit by switching the first switch to the on state when the second switch is off. Subsequently, after switching the second switch to the on state, the indoor and outdoor control circuits switch the first switch to the off state to activate the outdoor unit, thereby reducing the standby power of the outdoor unit.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2013-137116

[0005] However, in the technology of Patent Document 1 mentioned above, when the outdoor unit is connected to a high-capacity smoothing section, a surge current will flow in the smoothing section when the main relay is turned on to keep the outdoor unit running. Therefore, an additional circuit is needed to prevent the surge current. As a result, there is a problem of large-scale air conditioning units and high implementation costs. Summary of the Invention

[0006] This disclosure is made in view of the above circumstances, and its purpose is to obtain an air conditioning device that can be implemented at a low cost.

[0007] To address the aforementioned issues and achieve the objective, the air conditioning unit disclosed herein includes an indoor unit and an outdoor unit, which are connected via three core wires: a power line, a common line, and a signal line. Commercial power supplied to either the indoor or outdoor unit is supplied via the power line and the common line. The indoor unit includes: a first switch for opening and closing the connection between the power line and the signal line; and an indoor control unit that actuates the first switch to supply AC voltage from the commercial power supply between the signal line and the power line. The outdoor unit includes: a second switch for opening and closing the connection between the power line and the outdoor unit; a rectifier connected to the downstream of the second switch for rectifying the AC voltage; and a smoothing unit for smoothing the output of the rectifier. The outdoor unit also includes: a third switch that, in the off state, connects the signal line and a resistor connected to the downstream of the second switch, and in the on state, becomes an open circuit; and an outdoor control unit that controls the second and third switches. When the indoor control unit and the outdoor control unit start the outdoor unit from the standby state, the first switch is turned on when the third switch is off, thereby allowing the surge current to flow through the indoor unit to the smoothing section of the outdoor unit to charge the smoothing section. After charging, the second switch is turned on, and then the first switch is turned off and the third switch is turned on.

[0008] The air conditioning unit disclosed herein achieves the effect of being implemented at a low cost. Attached Figure Description

[0009] Figure 1 This is a diagram showing a structural example of the air conditioning device according to Embodiment 1.

[0010] Figure 2 This is a timing diagram showing the sequence of operations of the air conditioning unit according to Embodiment 1.

[0011] Figure 3 This is a diagram illustrating the flow pattern of the surge current when the outdoor unit of the air conditioning device according to Embodiment 1 is started.

[0012] Figure 4 This is a diagram illustrating the flow of current during normal operation of the air conditioning unit according to Embodiment 1.

[0013] Figure 5 This is a diagram showing a structural example of the air conditioning device involved in Embodiment 2.

[0014] Figure 6 This is a timing diagram showing the sequence of operations of the air conditioning unit involved in Embodiment 2.

[0015] Figure 7This is a diagram illustrating an example of the structure of a processing circuit in which the processing circuit of the air conditioning device according to embodiments 1 and 2 is implemented by a processor and a memory.

[0016] Figure 8 This is a diagram illustrating an example of the structure of the processing circuit in the case where the processing circuit of the air conditioning device according to embodiments 1 and 2 is composed of dedicated hardware. Detailed Implementation

[0017] Hereinafter, the air conditioning device according to the embodiments of the present disclosure will be described in detail based on the accompanying drawings.

[0018] Implementation Method 1

[0019] Figure 1 This is a diagram illustrating a structural example of the air conditioning unit according to Embodiment 1. In order to reduce standby power consumption, the air conditioning unit 101 cuts off the power supply to the control circuit (outdoor control unit 15) of the outdoor unit 3 during standby operation. The air conditioning unit 101 includes an indoor unit 2 and an outdoor unit 3.

[0020] Outdoor unit 3 is connected to AC power supply 1, which is a commercial power source. Furthermore, although in Figure 1 The diagram shows the connection between AC power supply 1 and outdoor unit 3, but AC power supply 1 can also be connected to indoor unit 2. Furthermore, although AC power supply 1 is a single-phase AC power supply, it can also be a three-phase AC power supply. In the air conditioning unit 101, indoor unit 2 and outdoor unit 3 are connected by three core wires: power cord 4, common wire 5, and signal wire 6.

[0021] The indoor unit 2 includes a first switch 7, an indoor control unit 8, an indoor rectifier unit 16, an indoor smoothing unit 17, an indoor control power generation unit 18, an indoor communication circuit 19, and an indoor current fuse 25. Additionally, the indoor unit 2 includes terminals T1 to T3.

[0022] The outdoor unit 3 includes a second switch 9, an outdoor rectifier 10, an outdoor smoothing unit 11, a third switch 12, a resistor 13, an outdoor communication circuit 14, an outdoor control unit 15, an outdoor control power generation unit 20, an inverter circuit 21, a noise filter 23, and an outdoor current fuse 26. Additionally, the outdoor unit 3 includes terminals T4 to T6.

[0023] Power line 4 is connected to terminals T1 and T4, common line 5 is connected to terminals T2 and T5, and signal line 6 is connected to terminals T3 and T6. Power line 4 is connected to AC power supply 1 via terminal T4, and common line 5 is connected to AC power supply 1 via terminal T5.

[0024] Inside the indoor unit 2, terminal T1 is connected to the indoor current fuse 25, terminal T2 is connected to connection point C4, and terminal T3 is connected to connection point C5.

[0025] In indoor unit 2, one end of indoor current fuse 25 is connected to terminal T1, which is connected to the power supply line 4, and the other end is connected to connection point C2. Indoor current fuse 25 blows if the current continues to exceed the allowable current.

[0026] The first switch 7 is connected to the power line 4 via connection point C2, indoor current fuse 25 and terminal T1, and to the signal line 6 via connection point C5 and terminal T3. That is, the first switch 7 is connected to the wiring closet that connects the power line 4 and the signal line 6 via the indoor current fuse 25.

[0027] The first switch 7 short-circuits the power line 4 and signal line 6 according to the on command from the indoor control unit 8, and opens the connection between the power line 4 and signal line 6 according to the off command from the indoor control unit 8. The first switch 7 can be a mechanical relay with A contact, i.e., an A-contact relay, or it can be made of semiconductor.

[0028] One end of the indoor rectifier 16 is connected to connection points C1 and C2, and the other end is connected to connection points C3 and C4. The indoor rectifier 16 outputs a rectified voltage from the AC power supply 1. The indoor rectifier 16 is constructed using diodes.

[0029] The indoor smoothing section 17 is connected to connection points C1 and C3. An example of the indoor smoothing section 17 is a smoothing capacitor. The indoor smoothing section 17 smooths the voltage output by the indoor rectifier section 16.

[0030] The indoor control power generation unit 18 is connected to connection points C1 and C3. The indoor control power generation unit 18 generates a low-voltage DC voltage based on the voltage smoothed by the indoor smoothing unit 17. The structure and method of the indoor control power generation unit 18 are not limited; it can be a DC / DC converter using a switching transformer or a direct step-down converter.

[0031] The indoor control unit 8 is connected to the remote controller (hereinafter referred to as the remote controller) 24. The indoor control unit 8 receives commands from the remote controller 24. In addition, the indoor control unit 8 is connected to the indoor control power generation unit 18, the first switch 7, and the indoor communication circuit 19.

[0032] The indoor control unit 8 is constructed using a microcomputer or similar components. The indoor control unit 8 operates based on the voltage generated by the indoor control power generation unit 18, thereby controlling the indoor unit 2. Specifically, the indoor control unit 8 controls the first switch 7 and the indoor communication circuit 19.

[0033] The indoor communication circuit 19 is connected to the common line 5 via connection point C4 and terminal T2, and to the signal line 6 via connection point C5 and terminal T3. The indoor communication circuit 19 transmits the change in potential to the indoor control unit 8, and changes the potential according to the operation of the indoor control unit 8, so that the indoor control unit 8 and the outdoor control unit 15 can communicate.

[0034] Inside the outdoor unit 3, terminal T4 is connected to the outdoor current fuse 26, terminal T5 is connected to connection point C10, and terminal T6 is connected to connection point C20.

[0035] In outdoor unit 3, one end of outdoor current fuse 26 is connected to terminal T4, and the other end is connected to second switch 9. That is, second switch 9 is connected to power line 4 via outdoor current fuse 26 and terminal T4. In addition, second switch 9 is connected to connection point C6.

[0036] The second switch 9 is opened and closed by the outdoor control unit 15. The second switch 9 can be a mechanical relay with an A-contact, i.e., an A-contact relay, or it can be made of semiconductor. A noise filter 23 for reducing normal-mode noise and common-mode noise is connected after the second switch 9. The noise filter 23 is connected to connection points C6 to C9. Although the structure of the noise filter 23 is not limited, the noise filter 23 may include, for example, an X capacitor, a Y capacitor (not shown), etc.

[0037] exist Figure 1 The diagram illustrates a noise filter 23 with two capacitors and two coils. In the noise filter 23, the first capacitor is connected to connection points C6 and C8, and the second capacitor is connected to connection points C7 and C9. Additionally, in the noise filter 23, the first coil is connected to connection points C6 and C7, and the second coil is connected to connection points C8 and C9. Connection point C7 is connected to connection point C11, connection point C8 is connected to connection point C10, and connection point C9 is connected to connection point C14.

[0038] The outdoor rectifier 10 is connected to the downstream stage of the noise filter 23 to rectify the AC voltage of the AC power supply 1. Specifically, the outdoor rectifier 10 is connected to connection points C9, C11, C16, and C18. Figure 1 The diagram shows an outdoor rectifier unit 10 that is a bridge diode for single-phase AC use with four diodes.

[0039] The outdoor rectifier section 10 has connection points C12 to C15. In the outdoor rectifier section 10, the first diode is connected to connection points C12 and C13, the second diode is connected to connection points C12 and C15, the third diode is connected to connection points C13 and C14, and the fourth diode is connected to connection points C14 and C15.

[0040] With this structure, in the outdoor rectifier section 10, the first diode is connected to the second diode via connection point C12, and the third diode is connected to the fourth diode via connection point C14. Connection point C12 is connected to connection point C11, and connection point C14 is connected to connection point C9. In addition, connection point C13 is connected to connection point C16, and connection point C15 is connected to connection point C18.

[0041] The outdoor smoothing section 11 is connected to connection points C16 and C18. The outdoor smoothing section 11 smooths the output of the outdoor rectifier section 10. Although the outdoor rectifier section 10 and the outdoor smoothing section 11... Figure 1 The circuit used is a full-wave rectifier circuit, but it is not limited to this. The outdoor rectifier section 10 and the outdoor smoothing section 11 can be configured to have coils and switching elements, or they can be rectifier circuits such as those for power factor control, or they can be rectifier circuits such as those for controlling the DC voltage across the outdoor smoothing section 11. Connection point C16 is connected to connection point C17, and connection point C18 is connected to connection point C19.

[0042] The outdoor control power generation unit 20 is connected to connection points C17 and C19. The outdoor control power generation unit 20 generates a low-voltage DC voltage based on the high-voltage voltage supplied via the outdoor smoothing unit 11. The structure and method of the outdoor control power generation unit 20 are not limited; it can be a DC / DC converter using a switching transformer or a direct step-down converter.

[0043] The outdoor control unit 15 is connected to the outdoor control power generation unit 20. Furthermore, the outdoor control unit 15 is connected to and controls the third switch 12, the second switch 9, the outdoor communication circuit 14, and the inverter circuit 21. The outdoor control unit 15 is constructed using a microcomputer or similar device. The outdoor control unit 15 is driven by the voltage from the outdoor control power generation unit 20, controlling the inverter circuit 21 to convert the DC voltage across the outdoor smoothing unit 11 into a three-phase AC voltage, thereby driving the compressor motor 22. Although in Figure 1 It is not recorded in the document, but it is also possible that the outdoor control unit 15 is connected to actuators and sensors such as thermistors used in the fan motor, four-way valve, LEV (Linear Expansion Valve), etc., and controls the outdoor unit 3 as a whole.

[0044] Inverter circuit 21 is connected to connection points C17 and C19. Additionally, inverter circuit 21 is connected to compressor motor 22. Inverter circuit 21 generates three-phase AC to rotate compressor motor 22.

[0045] The third switch 12 can be a mechanical relay with C contacts, i.e., a C-contact relay, or it can be made of semiconductor. In the third switch 12, the normally closed contact is connected to the connection point C20. The third switch 12 has no connection at the normally open contact, and one end of the resistor 13 is connected to the movable contact. The connection point C20 is connected to the terminal T6 connected to the signal line 6.

[0046] The other end of resistor 13 is connected to connection point C11, which serves as the downstream stage of the second switch 9. Outdoor communication circuit 14 is connected to common line 5 via connection point C10 and to signal line 6 via connection point C20. Outdoor communication circuit 14 transmits changes in potential to outdoor control unit 15 and changes the potential according to the operation of outdoor control unit 15, thereby enabling communication between indoor unit 2 and outdoor unit 3.

[0047] Next, the operation of the air conditioning unit 101 will be explained. Figure 2 This is a timing diagram showing the operation sequence of the air conditioning unit according to Embodiment 1. Here, the operation of the air conditioning unit 101 when the outdoor unit 3 is started from the standby state of the air conditioning unit 101 will be described.

[0048] Figure 2 Arrow 50 indicates the moment when the user operates the remote control 24. In the state before the user operates the remote control 24, i.e., state 1, the indoor unit 2 is powered by AC power 1.

[0049] State 1 is (1-1) to (1-9) below.

[0050] (1-1) Indoor control power generation unit 18 generates power.

[0051] (1-2) The indoor control unit 8 operates and waits for a signal from the remote control 24. However, since the indoor control unit 8 does not need to perform any actions other than receiving signals from the remote control 24, it keeps power consumption to a minimum by performing actions that minimize functionality.

[0052] (1-3) The first switch 7 is in the off state, and the power line 4 and the signal line 6 are open circuits.

[0053] (1-4) When the second switch 9 is in the off state, the AC power supply 1 is not connected to the downstream of the second switch 9 of the outdoor unit 3.

[0054] (1-5) The third switch 12 is in the open state, and its contact is connected to the normally closed contact side. That is, the third switch 12 is connected to the resistor 13 and the connection point C20.

[0055] (1-6) No current flows in AC power supply 1.

[0056] (1-7) In the air conditioning unit 101, although there is a current flowing in the amount corresponding to the standby power of the indoor unit 2, it is very small.

[0057] (1-8) The outdoor control power generation unit 20 does not operate, and the outdoor control unit 15 is not supplied with power.

[0058] (1-9) No communication is performed between the shared line 5 and the signal line 6.

[0059] Furthermore, since the noise filter 23 of Embodiment 1 is connected to the downstream side of the second switch 9, no voltage is applied to it even though the X capacitor is included in the noise filter 23, and therefore no invalid current flows. That is, the air conditioning unit 101 can make both the invalid power flowing in the outdoor unit 3 and the standby power 0 [A].

[0060] The air conditioning unit 101 transitions from state 1 to state 2. State 2 is as follows (2-1).

[0061] (2-1) The indoor control unit 8 moves from the standby power minimum state to the normal mode in preparation for operation. Therefore, although the current flowing in the AC power supply 1 increases slightly, it is very small, and thus... Figure 2 Illustrations omitted. Additionally, at this time, the air conditioning unit 101 can also activate the fan (not shown) of the indoor unit 2.

[0062] The air conditioning unit 101 transitions to state 3 after state 2. State 3 is as follows (3-1) to (3-4).

[0063] (3-1) The indoor control unit 8 sets the first switch 7 to the ON state. That is, the indoor control unit 8 short-circuits the power line 4 and the signal line 6. Therefore, in Figure 3 Surge current flows in the path shown.

[0064] Figure 3 This diagram illustrates the flow pattern of the surge current during startup of the outdoor unit of the air conditioning unit according to Embodiment 1. Figure 3 The diagram shows the path of the surge current flowing in outdoor unit 3 when it starts up. Furthermore, in... Figure 3 And the following Figure 4 The diagrams for connection points C1 to C20 and terminals T1 to T6 are omitted.

[0065] When the outdoor unit 3 is started, when the first switch 7 is turned on, the power line 4 is connected to the signal line 6. As a result, the current flows in the following order: AC power supply 1 → power line 4 → indoor current fuse 25 → first switch 7 → signal line 6 → third switch 12 → resistor 13 → outdoor rectifier 10 → outdoor smoothing section 11 → outdoor rectifier 10 → common line 5 side of noise filter 23 → AC power supply 1 (the opposite path if the current phase of AC power supply 1 is opposite), thus charging the outdoor smoothing section 11.

[0066] Resistor 13 functions as a limiting resistor to prevent inrush current when charging the outdoor smoothing section 11. Alternatively, resistor 13 can be a PTC (Positive Temperature Coefficient) thermistor. For example, even if a short circuit occurs in the outdoor smoothing section 11, inverter circuit 21, etc., resulting in a current flow larger than usual, a PTC thermistor will limit the current and reduce the risk of resistor 13 burning out because its resistance becomes very high when the temperature rises.

[0067] (3-2) Outdoor control power generation unit 20 generates control power.

[0068] (3-3) After the outdoor control unit 15 is supplied with power from the outdoor control power generation unit 20, it performs adjustment processing and prepares to start up.

[0069] (3-4) Regarding the current of AC power supply 1, after the surge current flows, a current corresponding to the power consumed by outdoor control unit 15, etc., and a current corresponding to the standby power of inverter circuit 21, etc., flows. Additionally, if the noise filter 23 includes an X capacitor, a current corresponding to the ineffective power flows. Figure 2 Illustrations omitted.

[0070] Furthermore, the first switch 7 of the indoor unit 2 can be any switch with a capacity that does not fail under the surge current and normal current of the indoor unit 2. In addition, the indoor current fuse 25 can be any current fuse with a capacity that does not melt under the surge current and normal current of the indoor unit 2, but melts when the current exceeds the allowable current of the indoor unit 2.

[0071] In Embodiment 1, the surge current flowing to the outdoor unit 3 as described above flows through the first switch 7 and the indoor current fuse 25. Therefore, the first switch 7 has a surge current capacity and specification capable of withstanding the surge current flowing when the outdoor unit 3 starts up. Furthermore, the indoor current fuse 25 has a capacity and specification that prevents it from melting under instantaneous current such as the surge current of the outdoor unit 3, and melts when the current continuously exceeds the allowable current of the indoor unit 2.

[0072] The air conditioning unit 101 transitions from state 3 to state 4. State 4 is as follows (4-1).

[0073] (4-1) The outdoor control unit 15 connects the second switch 9. At this time, the current for the AC power supply 1 will increase by an amount corresponding to the power consumption of driving the second switch 9, but... Figure 2 Illustrations omitted.

[0074] The air conditioning unit 101 transitions from state 4 to state 5. State 5 is as follows (5-1).

[0075] (5-1) The outdoor control unit 15 opens the contacts of the third switch 12 by activating it. At this time, the current to the AC power supply 1 increases by an amount corresponding to the power consumption of driving the third switch 12, but... Figure 2 Illustrations omitted.

[0076] The air conditioning unit 101 transitions from state 5 to state 6. State 6 is as follows (6-1).

[0077] (6-1) The indoor control unit 8 disconnects the first switch 7, thus opening the power line 4 and the signal line 6. As a result, the indoor communication circuit 19 and the outdoor communication circuit 14 can communicate via the common line 5 and the signal line 6.

[0078] Furthermore, although the third switch 12 and the first switch 7 are switched by turning on the third switch 12 and then turning off the first switch 7, as described in states 5 and 6, the order in which they are switched is not limited to this order. As long as the second switch 9 is turned on in state 4, the air conditioning unit 101 can also change the order of turning on the third switch 12 and turning off the first switch 7, and can even perform these actions simultaneously.

[0079] When communicating between the indoor control unit 8 and the outdoor control unit 15, for example, sometimes the indoor control unit 8 is the master and the outdoor control unit 15 is the slave, and the communication signal is sent first by the indoor control unit 8. In this case, the air conditioning unit 101 may turn on the third switch 12 and then turn off the first switch 7, after which the indoor control unit 8 starts communicating from the indoor communication circuit 19.

[0080] Alternatively, sometimes the outdoor control unit 15 is the master and the indoor control unit 8 is the slave, with the outdoor control unit 15 sending the communication signal first. In this case, the air conditioning unit 101 may turn on the third switch 12 after disconnecting the first switch 7, and then the outdoor control unit 15 will start communicating from the outdoor communication circuit 14.

[0081] Regardless of whether communication begins from the indoor communication circuit 19 or the outdoor communication circuit 14, in the air conditioning unit 101, communication will begin as long as at least the first switch 7 is in the off state and the third switch 12 is in the on state.

[0082] Assuming that the outdoor communication circuit 14 operates while the first switch 7 is in the ON state, this is equivalent to short-circuiting the potential of the common line 5 and the signal line 6. Since the signal line 6 and the power line 4 are at the same potential when the first switch 7 is in the ON state, the current flows in the following sequence: AC power supply 1 → power line 4 → indoor current fuse 25 → first switch 7 → indoor communication circuit 19 → common line 5 → AC power supply 1, resulting in a power short circuit and potentially causing a circuit malfunction.

[0083] Furthermore, assuming the indoor communication circuit 19 wants to start communication when the third switch 12 is in the off state, nothing will happen if the second switch 9 is off, but a power short circuit will occur if the second switch 9 is turned on. That is, the current flows in the following order: AC power supply 1 → outdoor current fuse 26 → second switch 9 → noise filter 23 → resistor 13 → third switch 12 → signal line 6 → indoor communication circuit 19 → common line 5 → AC power supply 1, resulting in a power short circuit. With such current flowing, if the outdoor control unit 15 turns on the third switch 12, an electric arc will be generated at the contacts, leading to a reduction in contact life and the occurrence of welding, etc. Therefore, in Embodiment 1, the air conditioning unit 101 starts communication when the first switch 7 is off and the third switch 12 is on.

[0084] The air conditioning unit 101 transitions from state 6 to state 7. State 7 is as follows (7-1).

[0085] (7-1) The outdoor control unit 15 starts operating and current flows from the AC power supply 1. Figure 4 The diagram shows how the current flows during normal operation.

[0086] Figure 4This diagram illustrates the current flow pattern during normal operation of the air conditioning unit according to Embodiment 1. During normal operation, the air conditioning unit 101 flows in the following path: AC power supply 1 → outdoor current fuse 26 → second switch 9 → power line 4 side of noise filter 23 → outdoor rectifier 10 → outdoor smoothing unit 11 → inverter circuit 21 → compressor motor 22 → inverter circuit 21 → outdoor smoothing unit 11 → outdoor rectifier 10 → common line 5 side of noise filter 23 → AC power supply 1. Furthermore, when the current phase of AC power supply 1 is opposite, the current flows in a path opposite to the above path. Additionally, current that operates the actuator also flows in the indoor unit 2.

[0087] In this way, when the outdoor unit 3 is started, the air conditioning unit 101 causes the surge current to flow through the first switch 7 and the resistor 13 provided after the third switch 12 to the outdoor smoothing section 11. That is, when the outdoor unit 3 is started, the air conditioning unit 101 causes the surge current to flow through the first switch 7 of the indoor unit 2 to the outdoor smoothing section 11, which is the smoothing section of the main circuit of the outdoor unit 3.

[0088] Therefore, the air conditioning unit 101 does not require a circuit for preventing surge current. The air conditioning unit 101 does not require circuit components such as relays, resistors, or coils for preventing surge current. Therefore, the number of switches installed in the outdoor unit 3 can be reduced, and thus it can be manufactured at low cost without becoming large.

[0089] Thus, according to Embodiment 1, the air conditioning unit 101, which cuts off the power supply to the outdoor control unit 15 during standby to reduce the standby power of the outdoor unit 3, allows the surge current to flow to the outdoor smoothing section 11 via the first switch 7 of the indoor unit 2 and the resistor 13 located after the third switch 12 of the outdoor unit 3 when the outdoor unit 3 is started. With this structure, the air conditioning unit 101 reduces standby power and eliminates the need for a switch to prevent surge current. Therefore, the air conditioning unit 101 can be miniaturized, and thus can be implemented at low cost.

[0090] Implementation Method 2

[0091] Next, use Figure 5 as well as Figure 6 Implementation method 2 will be described. In implementation method 1, the case where there is one indoor unit 2 was described, but in implementation method 2, the case where there are two or more indoor units will be described.

[0092] Figure 5 This is a diagram illustrating a structural example of the air conditioning device according to Embodiment 2. Figure 5 Among the various constituent elements, the realization and Figure 1The same reference numerals are used to indicate the same functional components of the air conditioning unit 101 in Embodiment 1 shown, and repeated descriptions are omitted.

[0093] Air conditioning unit 102 includes indoor units 2 and 2a and outdoor unit 3a. In air conditioning unit 102, indoor unit 2 is connected to outdoor unit 3a, and indoor unit 2a is connected to outdoor unit 3a. In air conditioning unit 102, indoor unit 2 and outdoor unit 3a are connected by a power line 4, a common line 5, and a signal line 6, and indoor unit 2a and outdoor unit 3a are connected by a power line 4a, a common line 5a, and a signal line 6a.

[0094] Indoor unit 2a has the same structure as indoor unit 2. That is, indoor unit 2a includes a first switch 7a, an indoor control unit 8a, an indoor rectifier 16a, an indoor smoothing unit 17a, an indoor control power generation unit 18a, an indoor communication circuit 19a, and an indoor current fuse 25a.

[0095] The first switch 7a, indoor control unit 8a, indoor rectifier 16a, and indoor smoothing unit 17a each have the same function and perform the same operation as the first switch 7, indoor control unit 8, indoor rectifier 16a, and indoor smoothing unit 17a. Furthermore, the indoor control power generation unit 18a, indoor communication circuit 19a, and indoor current fuse 25a each have the same function and perform the same operation as the indoor control power generation unit 18, indoor communication circuit 19, and indoor current fuse 25a. Connection points C1a to C5a are located in the same positions as connection points C1 to C5. Additionally, inside the indoor unit 2a, each component of the indoor unit 2a has the same connection structure as each component of the indoor unit 2. The indoor control unit 8a is connected to the remote control 24a.

[0096] In addition, indoor unit 2a has terminals T1a to T3a. Terminals T1a to T3a are the same as terminals T1 to T3. Terminal T1a of indoor unit 2a is connected to terminal T4 of outdoor unit 3a, and terminal T2a of indoor unit 2a is connected to terminal T5 of outdoor unit 3a. In addition, terminal T3a of indoor unit 2a is connected to terminal T7 of outdoor unit 3a.

[0097] In addition to the components of outdoor unit 3, outdoor unit 3a also includes a first reverse element diode 30, a second reverse element diode 30a, an outdoor communication circuit 14a, and a terminal T7.

[0098] Terminal T4 of outdoor unit 3a is connected to terminal T1 via power line 4, and also to terminal T1a via power line 4a. Terminal T5 of outdoor unit 3a is connected to terminal T2 via common line 5, and also to terminal T2a via common line 5a. Terminal T6 of outdoor unit 3a is connected to terminal T3 via signal line 6, and terminal T7 of outdoor unit 3a is connected to terminal T3a via signal line 6a.

[0099] In outdoor unit 3a, a connection point C41 is provided in the wiring closet where terminal T5 is connected to connection point C10. Additionally, a connection point C43 is provided in the wiring closet where connection point C20 is connected to the third switch 12.

[0100] A first reverse element, diode 30, is disposed in the wiring closet connecting connection point C43 and connection point C20. Connection point C42 is provided in the wiring closet connecting terminal T7 and connection point C43. Outdoor communication circuit 14a is connected to connection points C41 and C42. A second reverse element, diode 30a, is disposed in the wiring closet connecting connection points C42 and connection point C43.

[0101] In outdoor unit 3a, the anode of the first reverse element diode 30 is connected to the signal line 6 via connection point C20, and the cathode is connected to the normally closed contact of the third switch 12 via connection point C43.

[0102] The anode of the second reverse element diode 30a is connected to connection point C42, and the cathode is connected to connection point C43. Thus, the anode of the second reverse element diode 30a is connected to signal line 6a via connection point C42. Furthermore, the cathode of the second reverse element diode 30a is connected to signal line 6 via connection points C43 and C20, and is also connected to the normally closed contact of the third switch 12 via connection point C43.

[0103] The outdoor communication circuit 14a has the same function and performs the same operation as the outdoor communication circuit 14. The outdoor communication circuit 14a of the outdoor unit 3a communicates with the indoor communication circuit 19a via the common line 5a and the signal line 6a. Thus, the outdoor unit 3a communicates with the indoor unit 2a via the common line 5a and the signal line 6a.

[0104] Next, the operation of the air conditioning unit 102 will be explained. Hereinafter, the operation of the air conditioning unit 102 will be explained in terms of the differences between the operation of the air conditioning unit 102 according to Embodiment 2 and the operation of the air conditioning unit 101 according to Embodiment 1.

[0105] Air conditioning unit 102 differs from air conditioning unit 101 in that air conditioning unit 102 has multiple indoor units. In addition, air conditioning unit 102 and air conditioning unit 101 differ in that the outdoor unit 3a of air conditioning unit 102 has a first reverse element diode 30, a second reverse element diode 30a, an outdoor communication circuit 14a, and a terminal T7.

[0106] Figure 6 This is a timing diagram showing the operation sequence of the air conditioning unit according to Embodiment 2. Here, the operation of the air conditioning unit 102 when the outdoor unit 3a starts and operates from the standby state of the air conditioning unit 102 will be described.

[0107] Consider the scenario where the user operates the remote control 24a for indoor unit 2a. Figure 6 In this context, the operation of the air conditioning unit 102 in states 1A and 2A is the same as the operation of the air conditioning unit 101 in states 1 and 2 as described in Embodiment 1, so the description is omitted.

[0108] The air conditioning unit 102 transitions from state 2A to state 3A. State 3A consists of the following (3A-1) to (3A-4).

[0109] (3A-1) The indoor control unit 8a puts the first switch 7a of the indoor unit 2a into the ON state. That is, the indoor control unit 8a short-circuits the power line 4a and the signal line 6a. As a result, surge current flows in the following path.

[0110] That is, the current flows in the following order: AC power supply 1 → power line 4a → indoor current fuse 25a of indoor unit 2a → first switch 7a of indoor unit 2a → signal line 6a → diode 30a for second reverse element → third switch 12 of outdoor unit 3a → resistor 13 → outdoor rectifier 10 → outdoor smoothing section 11 → outdoor rectifier 10 → common line 5 side of noise filter 23 → AC power supply 1, thereby charging the outdoor smoothing section 11.

[0111] However, unlike air conditioner 101, air conditioner 102 does not flow current when the current phase of AC power supply 1 is opposite (opposite phase). This is because air conditioner 102 has a diode 30a for a second reverse element.

[0112] The operations of (3A-2) to (3A-4) in state 3A are the same as those of (3-2) to (3-4) described in embodiment 1, so the description is omitted. In addition, the operation of the air conditioning unit 102 in states 4A to 7A is the same as the operation of the air conditioning unit 101 in states 4 to 7 described in embodiment 1, so the description is omitted.

[0113] Here, the effect of the air conditioning unit 102 having a first reverse element diode 30 and a second reverse element diode 30a will be explained. The anode of the first reverse element diode 30 is connected to the signal line 6 and the outdoor communication circuit 14. Similarly, the anode of the second reverse element diode 30a is connected to the signal line 6a and the outdoor communication circuit 14a.

[0114] Communication between indoor unit 2 and outdoor unit 3a, and communication between indoor unit 2a and outdoor unit 3a, are performed separately. Therefore, if the first reverse element diode 30 and the second reverse element diode 30a are not present in outdoor unit 3a, signal line 6 and signal line 6a will be at the same potential. In this case, outdoor unit 3a cannot detect the potential difference of the signal with indoor units 2 and 2a via the communication circuit, and therefore cannot generate a potential difference; consequently, communication with indoor units 2 and 2a cannot be performed. Thus, when multiple indoor units 2 and 2a are connected to outdoor unit 3a, the first reverse element diode 30 and the second reverse element diode 30a are required.

[0115] The resistance value of resistor 13 is set such that the surge current flowing when the first switch 7 or the first switch 7a is turned on is below the allowable current of the first reverse element diode 30 and the second reverse element diode 30a. Increasing the resistance value of resistor 13 allows for the selection of first reverse element diodes 30 and 30a with smaller current capacities. Conversely, decreasing the resistance value of resistor 13 shortens the charging time for the outdoor smoothing section 11.

[0116] Furthermore, in Embodiment 2, the case where the air conditioning unit 102 has two indoor units 2 and 2a was described, but the air conditioning unit 102 may also have three or more indoor units. In this case, the air conditioning unit 102 only needs to have the same number of outdoor communication circuits as the number of indoor units it has.

[0117] Even when the air conditioning unit 102 has three or more indoor units, each indoor unit is connected to a power cord, a common line, and a signal line. Furthermore, each indoor unit is connected to terminal T4 of the outdoor unit via a power cord and to terminal T5 of the outdoor unit via the common line. Additionally, the outdoor unit has terminals for the signal lines of each indoor unit and an outdoor communication circuit for each indoor unit. Each indoor unit is connected to the signal line terminals of its respective indoor unit and the outdoor communication circuit of its respective indoor unit.

[0118] Thus, according to Embodiment 2, in the air conditioning unit 102, even when the outdoor unit 3a is connected to two indoor units 2, 2a, the surge current protection switch can be omitted, just like in the air conditioning unit 101. As a result, since the air conditioning unit 102 can be miniaturized, it can be implemented at a low cost.

[0119] In addition, the outdoor unit 3a of the air conditioning unit 102 is equipped with a first reverse element diode 30 and a second reverse element diode 30a, so even when the outdoor unit 3a is connected to two indoor units 2 and 2a, the outdoor unit 3a can communicate with the indoor units 2 and 2a.

[0120] Here, the hardware structure of the indoor control unit 8, the indoor control unit 8a of the air conditioning unit 102, and the outdoor control unit 15 of the air conditioning units 101 and 102 will be described. Furthermore, since the indoor control units 8 and 8a and the outdoor control unit 15 have the same hardware structure, the hardware structure of the outdoor control unit 15 will be described here.

[0121] The outdoor control unit 15 is implemented by a processing circuit. The processing circuit can be a processor that executes a program stored in memory, or it can be dedicated hardware.

[0122] Figure 7 This diagram illustrates a structural example of the processing circuit in the case where the processing circuit of the air conditioning device according to embodiments 1 and 2 is implemented by a processor and a memory. The outdoor control unit 15 can be controlled by... Figure 7 The control circuit 90 shown is implemented by processor 91 and memory 92.

[0123] Processor 91 is a CPU (Central Processing Unit, also known as a central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, processor, DSP (Digital Signal Processor)) or a system LSI (Large Scale Integration). Memory 92 can be exemplified by non-volatile or volatile semiconductor memories such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), and EEPROM (Electrically Erasable Programmable Read-Only Memory). However, memory 92 is not limited to these and can also be a magnetic disk, optical disk, compressed optical disk, mini-disk, or DVD (Digital Versatile Disc).

[0124] The memory 92 stores a program that performs the functions of the outdoor control unit 15. The processor 91 performs processing based on the outdoor control unit 15 by reading and executing the program stored in the memory 92. The program stored in the memory 92 can also be described as multiple commands that cause the computer to execute in a sequence or method corresponding to the outdoor control unit 15. The memory 92 also serves as temporary storage when the processor 91 performs various processes.

[0125] The program executed by processor 91 may also be a computer program product that can be executed by a computer, the computer program product having a computer-readable and non-transitory recording medium including multiple commands for performing data processing.

[0126] Figure 8This diagram illustrates an example of the structure of the processing circuit in the case where the processing circuit of the air conditioning unit according to embodiments 1 and 2 is constructed using dedicated hardware. The processing circuit 93 can be, for example, a single circuit, a composite circuit, a programming processor, a parallel programming processor, an ASIC (Application Specific Integrated Circuit), a FPGA (Field-Programmable Gate Array), or a combination thereof. Furthermore, the functions of the outdoor control unit 15 can be partially implemented by dedicated hardware and partially by software or firmware.

[0127] The structure shown in the above embodiments is an example and can be combined with other known technologies, or the embodiments can be combined with each other. A part of the structure can also be omitted or changed without departing from the spirit of the subject.

[0128] Explanation of reference numerals in the attached figures

[0129] 1...AC power supply; 2, 2a...Indoor unit; 3, 3a...Outdoor unit; 4, 4a...Power cord; 5, 5a...Common line; 6, 6a...Signal line; 7, 7a...First switch; 8, 8a...Indoor control unit; 9...Second switch; 10...Outdoor rectifier; 11...Outdoor smoothing unit; 12...Third switch; 13...Resistor; 14, 14a...Outdoor communication circuit; 15...Outdoor control unit; 16, 16a...Indoor rectifier; 17, 17a...Indoor smoothing unit; 18, 18a...Indoor control power generation unit; 19, 19a...Indoor power supply... Signal circuit; 20...Outdoor control power generation unit; 21...Inverter circuit; 22...Compressor motor; 23...Noise filter; 24, 24a...Remote control; 25, 25a...Indoor current fuse; 26...Outdoor current fuse; 30...Diode for first reverse element; 30a...Diode for second reverse element; 90...Control circuit; 91...Processor; 92...Memory; 93...Processing circuit; 101, 102...Air conditioning unit; C1~C20, C41~C43, C1a~C5a...Connection points; T1~T7, T1a~T3a...Terminals.

Claims

1. An air conditioning unit comprising an indoor unit and an outdoor unit, wherein the indoor unit and the outdoor unit are connected via three core wires: a power cord, a common wire, and a signal wire, and commercial power supplied to either the outdoor unit or the indoor unit is supplied via the power cord and the common wire. The indoor unit has: The first switch opens or closes the connection between the power line and the signal line; and The indoor control unit actuates the first switch, supplying AC voltage from the commercial power supply between the signal line and the power line. The outdoor unit has the following features: The second switch opens and closes the connection between the power cord and the outdoor unit. The rectifier section is connected to the downstream stage of the second switch to rectify the AC voltage. The smoothing section smooths the output of the rectifier section; The third switch, in the off state, connects the signal line and the resistor connected to the downstream stage of the second switch; in the on state, it becomes an open circuit. The outdoor control unit controls the second and third switch devices. When the indoor control unit and the outdoor control unit start the outdoor unit from standby mode, they connect the first switch when the third switch is off, thereby allowing surge current to flow through the indoor unit to the smoothing section of the outdoor unit to charge the smoothing section. After charging, the second switch is connected, and then the first switch is disconnected and the third switch is connected.

2. The air conditioning device according to claim 1, wherein, The first and second switches are A-contact relays. The third switch is a C-contact relay.

3. The air conditioning device according to claim 1 or 2, wherein, The first switch has the capacity to withstand surge current flowing to the smooth part of the outdoor unit.

4. The air conditioning device according to any one of claims 1 to 3, wherein, The indoor unit also includes a fuse connected to the upstream of the first switch. The fuse will not blow even if a surge current flows to the smooth part of the outdoor unit, and will blow if the current exceeds the allowable current of the indoor unit.

5. The air conditioning device according to any one of claims 1 to 4, wherein, It also includes a noise filter, which is connected to the stage following the second switch and the stage preceding the rectifier, and reduces both constant-mode noise and common-mode noise. The noise filter includes an X capacitor.

6. The air conditioning device according to any one of claims 1 to 5, wherein, The indoor unit consists of multiple indoor units. The indoor unit and the outdoor unit are connected by three core wires: the power cord, the common wire, and the signal wire. The outdoor unit also includes a number of diodes for reverse elements, the same number as the number of indoor units. The anode of these diodes is connected to the signal line, and the cathode is connected to the normally closed contact of the third switch. Each of the signal lines connected to the indoor unit is connected to the reverse element using a diode.

7. The air conditioning device according to claim 6, wherein, The resistor has a resistance value that makes the surge current below the allowable current of the diode for the reverse element.

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