JP2002213803A - Indoor-outdoor communication control device for air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost and high-speed indoor-outdoor communication control device of a three-core type in a separate type air conditioner. SOLUTION: A DC power supply part obtained by half-wave rectification is provided in each of indoor and outdoor units, and a current-loop communication circuit using a PNP transistor and an NPN transistor which has high breakdown voltage and operates at a high speed as switching elements for transmission in each unit is formed. A bias circuit which drives each transmission switching element is formed by using a constant-voltage circuit part of about several tens of volts provided in the DC power supply part in each unit, and a photocoupler of a low-voltage type which turns the bias circuit ON/OFF is provided, and thereby high-speed switching of a current loop current is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indoor / outdoor communication control device for a separate type air conditioner operated by a commercial power supply.

[0002]

2. Description of the Related Art In a separate type air conditioner, which is divided into an indoor unit and an outdoor unit, a control unit including a microcomputer is provided in each unit. In order to transmit information and control signals to each other, communication between the control units (hereinafter referred to as indoor / outdoor communication) must be performed. As a conventional example of the indoor / outdoor communication control device of this air conditioner,
As proposed in JP-A-303516, a current loop type communication circuit configuration as shown in FIG. 14 using a DC power supply unit formed by rectifying a commercial power supply on the outdoor unit side as a power supply is adopted.

The conventional indoor / outdoor communication control device shown in FIG. 14 can connect both indoor and outdoor units by only two AC power supply lines 3 and one communication signal line 4, and
By forming a communication circuit using the first DC power supply unit 6 in the outdoor unit 2 as a power supply, transmission and reception can be performed independently of the power supply phase of the commercial power supply 5.

A photocoupler is used as a switching element for transmission and a current detection element for reception in a current loop communication circuit. By controlling the transmission photocoupler of the transmission unit ON / OFF in a state where the transmission photocoupler of the reception unit is kept ON by a control signal of the control unit 15 or 16 provided in each unit, The loop current of the current loop communication circuit is turned on / off, and the loop current is detected by the photocouplers 9 and 11 in both units. The detection by the photocouplers 9 and 11 in both units has the advantage that the receiving unit can receive and the transmitting unit can communicate while confirming the transmission result.

In the case where the indoor unit is an air conditioner that is a power supply unit, communication starts first from a communication from the outdoor unit 2 that is the power supply side to the indoor unit 1. That is, the photocoupler 25, which is a transmission switching element in the indoor unit 1, is kept in the ON state, and the control unit 16 of the outdoor unit turns the transmission photocoupler 28 in the outdoor unit in accordance with the transmission signal.
N / OFF. At this time, the transmission signal can be received by both receiving couplers.

[0006] When the transmission from the outdoor unit 2 to the indoor unit 1 is completed, the transmission from the indoor unit 1 to the outdoor unit 2 is performed, and then the transmission and reception are sequentially performed alternately to continue the indoor and outdoor communication. Can be done.

[0007]

In a conventional current loop type indoor / outdoor communication control device, an indoor unit and an outdoor unit are connected by three connection wires consisting of a power supply line and one communication signal line. However, it is required that the circuit element in each unit is not damaged even if the wiring is erroneously made during the wiring. Depending on the combination of the wiring, a voltage exceeding 300 V may be applied to both ends of the switching element for transmission at the time of incorrect connection of the connecting wire in the AC 200 V model, and furthermore, it is necessary to provide insulation between the communication signal line and the control microcomputer. For this reason, it is necessary to use a photocoupler having a high withstand voltage for the transmission switching element.

On the other hand, with the progress of networking of home appliances, a form in which either an indoor unit or an outdoor unit is connected to a network in an air conditioner is being studied. However, it is difficult in terms of cost to provide both units with a means for communicating with an external network constituted by radio or the like, and a mode in which only one unit has high-speed communication means with the network has been considered.

In such a situation, for example, when a program of JAVA (registered trademark) is received from a network and the received program is transmitted to the other unit, if the speed of indoor / outdoor communication is low, the communication speed becomes low. In order to transmit the program data to other units without losing it, the unit having the high-speed communication means with the network has a RAM equivalent to the program and temporarily holds the program data, or Communication speed itself must be limited.

[0010] Furthermore, as the control itself is advanced and the parameters required for the control are increasing, there is also an inherent advantage that the control parameters can be transmitted at an earlier timing. Is desired.

However, a photocoupler, which is a switching element used in a conventional circuit, generally increases the cost as the withstand voltage increases, the switching speed is slow, and the conventional indoor / outdoor communication using a high withstand voltage type photocoupler. It has been difficult for the control device to achieve a communication speed exceeding several kbps.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a conventional transmission switching element having a high withstand voltage of 300 V or more, which is necessary as a withstand voltage of the element in consideration of incorrect connection and the like. Instead of the high breakdown voltage type photocoupler, the high breakdown voltage type transistor and F
Using a high-speed switching element such as an ET, a constant voltage circuit section provided in the DC power supply section to form a bias circuit to drive the element, and an opening and closing that also serves as insulation between the control section and the base terminal of the element Means is newly provided in both units.

[0013] One of the transmitting switching elements is P
By using an NP transistor and an NPN transistor on the other side, providing a constant voltage circuit section of about several tens of volts in each DC power supply section, and providing switching means between the base terminal of the high voltage switching element, A bias circuit can be formed so that the base current of the transistor does not flow through the current detection elements of both current loops. Also, by providing the constant voltage circuit unit, insulation between the control unit and the current loop circuit, which is a communication signal circuit that is not insulated from the commercial power line,
Since it can be performed by a high-speed photocoupler of a low voltage type of about several tens of volts, by using a circuit of the present invention that uses a high-voltage transistor of a high speed type together,
This enables high-speed indoor / outdoor communication of the air conditioner.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows a circuit configuration of a first embodiment. The indoor unit 1 of the air conditioner is a unit on the power supply side connected to a commercial power supply 5 by an outlet, and includes two power supply lines 3a and 3b and one communication signal line 4.
Outdoor unit 5 which is the unit on the power supply side via
Is connected to

The indoor unit 1 and the outdoor unit 2
It has control units 15 and 16 each composed of a microcomputer or the like for controlling each unit and transmitting / receiving indoor / outdoor communication signals. The control units 15 and 16 are both operated by a DC power supply unit that is formed by full-wave rectification from the commercial power supply 5,
Since it is not related to the present invention, notation is omitted in the drawings after FIG.

Inside the outdoor unit 2, there is provided a first DC power supply 6 obtained by half-wave rectification of the commercial power supply 5, and the positive potential of the smoothing capacitor C1 in the first DC power supply 6 is An emitter terminal of a PNP transistor 8 serving as a switching element for transmission provided in the outdoor unit 2 is connected, and a collector terminal of the PNP transistor 8 for detecting a collector current of the PNP transistor 8 serving as a communication signal is connected to a collector terminal of the PNP transistor 8. Are connected.

The positive potential of the smoothing capacitor C1 in the first DC power supply 6 is connected to a first constant voltage element 2 such as a Zener diode or a three-terminal regulator IC.
8 is connected, the first DC power supply unit 6 is used as a power supply,
A constant voltage circuit of a negative voltage based on the emitter terminal potential of the transistor 8 is configured.

The base terminal of the PNP transistor 8 has
Driven by the control unit 16 in the outdoor unit 2, the PN
A second photocoupler 10 is connected to turn on / off the base current of the P transistor 8, and its emitter terminal is connected to the low potential side of the first constant voltage element 28. The value of the base resistor 21 is set in the PNP transistor 8 so that when the second photocoupler 10 driven by the control unit 16 is turned on, a base current flows to be in an ON state. Second
By driving the photocoupler 10, the PNP transistor 8 can be turned ON / OFF.

The voltage of the first constant voltage element 28 connected to the first DC power supply section 6 is set to be equal to or less than the withstand voltage of the second photocoupler 10 to be used. The voltage applied at the time of OFF can be limited to the rated voltage or less.

On the other hand, the indoor unit 1 is provided with a second DC power supply 7 obtained by half-wave rectification of a commercial power supply, and a negative potential of the second DC power supply 7 and the first DC power supply. The unit 6 is connected via the power supply line 3b so that the potential on the negative side of the unit 6 becomes equal.

An NPN transistor 11 is used as a transmission switching element on the indoor unit 1 side.
A third photocoupler 1 for detecting the collector current of the NPN transistor 11 at the collector terminal of the N transistor 11
3 are connected.

Similarly, in the indoor unit 1, the second
Is connected to the second DC power supply unit 7 to form a constant voltage circuit of about 10 to 30 V based on the emitter potential of the NPN transistor 11, and its output terminal and the NPN transistor A base resistor 22 and a fourth photocoupler 14 driven by the control unit 17 are connected between the base terminals 11. By turning on / off the fourth photocoupler 14 by the control unit 17,
The PNP transistor 11 is controlled.

The NPN transistor 11 and the PNP transistor 8, which are switching elements for signal transmission,
Since a voltage exceeding 300 V is applied when the power supply lines 3a and 3b are wired incorrectly,
A transistor with a withstand voltage of 0 V is used.

In order to limit the value of the current flowing through the communication signal line 4, the current limiting resistors 17 and 18 are connected to the protection diodes 19 and 20 via the communication signal line 4 at the time of incorrect connection in construction or the like. They are connected in series.

At the time of transmission, the control units 15 and 16 turn on / off the second and fourth photocouplers 10 and 14, respectively, in accordance with the transmission signal. The voltage between both ends of the first constant voltage element 28 and the second constant voltage element 29 composed of a Zener diode or the like is a constant voltage that is always maintained at about 10 to 30 V, and the second photocoupler 10 or the fourth Is turned on, the base resistance 2
Base currents determined by 1 and 22 flow through the PNP transistor 8 or the NPN transistor 11, respectively.

Since the base current is set so that a current flowing through the current loop can sufficiently flow, the PNP transistor 8 or the NPN transistor 11 can be turned on.

Here, the base current which is a bias current flowing when the second photocoupler 10 or the fourth photocoupler 14 is turned on is changed to the first photocoupler 9 or the third photocoupler 13 which is a receiving element. Flows to
Even when the current does not actually flow through the current loop, such as when the NP transistor 8 or the NPN transistor 11 is short-circuited and the data transmission is not established, the current flows through the receiving coupler of the transmitting unit. This causes a problem such as failure to detect the flow and transmission failure.

In order to solve this problem, in the present embodiment, the first photocoupler 9 and the third photocoupler 13 which are photocouplers for reception are replaced with the transistor collectors which are switching elements in each unit. By connecting to the terminal side, energization / interruption of the current of the current loop and reception by the first and third photocouplers are in one-to-one correspondence.

As described above, unlike the photocoupler (not shown) of the transmission switching element in the conventional circuit, in the present invention, the constant voltage circuit provided in each of the DC power supplies 6 and 7 as a constant voltage circuit is provided. The elements 28 and 29 allow the second photocoupler 10 and the fourth photocoupler 14
Can be limited to 30 V or less when both terminals are OFF. Therefore, a general-purpose coupler having a withstand voltage of about 50 V or a higher-speed type photocoupler can be used as the photocouplers 13 and 14. In general, a high-speed photocoupler has a low withstand voltage and cannot be used as a transmission switching element in a conventional circuit. However, in the circuit of the present embodiment, a low withstand voltage type photocoupler can be used. Then, a coupler having a higher switching speed than the conventional circuit can be used.

In the conventional circuit, a photocoupler is used as a transmission element in order to insulate the control unit 16 from the current loop communication circuit. However, in the present embodiment, the second and fourth photocouplers are used. By ensuring insulation by 10 and 14, it is possible to use a coupler having a low withstand voltage and a higher speed.

In the communication circuit of the present embodiment, the total switching time from when the transmitting unit outputs a transmission signal to when the current loop current is turned on or off is determined by the second photocoupler 10 and the PNP transistor 8,
Alternatively, the fourth photocoupler 14 and the NPN transistor 1
1 is the sum of the switching times.

In this embodiment, in order to shorten the switching time, the base-emitter resistors 23 and 24 of about several kΩ are provided between the base and the emitter of the PNP transistor 8 and the NPN transistor 11, respectively. Excess carriers are emitted to increase the switching speed at the time of OFF. Since the second and fourth photocouplers 10 and 14 are faster couplers than the high-withstand-voltage coupler used in the conventional circuit, the OFF time of the PNP transistor 8 or the NPN transistor 11 and the second and fourth photocouplers 10 and 14 are different. Even if the sum of the off-time of the photocouplers 10 and 14 is taken into account, the off-speed can be increased to about 10 times compared with the transmission switching time of the conventional circuit.

As for the switching speed at the time of ON, the switching ON speed of the photocoupler is OF
Because it is much faster than F,
Even if the sum with the N time is considered, the ON speed is slow as a whole system, and the effect can be almost ignored.

As described above, by using the circuit of the present embodiment, it is possible to realize a speedup equivalent to about 10 times as compared with the conventional circuit.

The communication is performed by transmission from the outdoor unit 2 which is the unit to which power is supplied to the indoor unit 1, and thereafter, transmission and reception are performed by communication that is performed alternately and sequentially.

Data such as the indoor temperature, the outdoor temperature, and the number of rotations of the compressor, which are communicated indoors and outdoors in the air conditioner, have a packet structure in which some data are put together. FIG. 2 shows an example of a packet to be communicated. The packet is composed of a header part and a data part, and the header part describes an identification code of the packet. The identification code describes the signal from which unit or the packet in which the data is written. Note that the transmission and reception are not performed one packet at a time, but the packet transmission may be performed alternately several times. FIG. 3 shows a flowchart in the case of performing the transmission and reception twice.

In the packet, different types of data may be transmitted, or the same data may be transmitted a plurality of times to perform error correction. By employing error correction, it is also possible to configure a communication control device that is resistant to disturbance.

(Embodiment 2) FIG. 4 shows the configuration of Embodiment 2. A P-channel FET 31 is used as a transmission switching element instead of the PNP transistor 8,
N-channel FET 32 instead of N-transistor 11
Are used.

The operation principle is the same as that in the case where the transmission switching element is a transistor. However, in a multi air conditioner in which a plurality of indoor units 1 are connected to one outdoor unit 2, the outdoor unit which is a power supply unit Since the first DC power supply unit 6 provided in the unit 2 forms a current loop communication circuit with each indoor unit 1, a voltage drop of the DC power supply unit during a period in which a plurality of current loop currents flow simultaneously increases. . In a circuit using a transistor as a switching element for transmission, a bias current for flowing a current loop current and a base current becomes a load current of the circuit, and therefore, the first DC power supply when the current loop current is ON and OFF. Part 6
Voltage fluctuation becomes larger than that of the conventional circuit.

On the other hand, the FET is a voltage driving element, and it is not necessary to supply a base current when turning on the transmission switching element. Therefore, a voltage drop of the first DC power supply unit 6 when the current loop current flows is suppressed, and
The design of the bias circuit is easier than a circuit using a transistor.

Further, as shown in FIG. 4, the second photocoupler 10 and the fourth photocoupler 14 are high-speed type couplers, and the charge time is quickly extracted from the gate terminal of each FET, thereby shortening the OFF time. In addition, the speed of internal and external communication can be further increased.

(Embodiment 3) FIG. 5 shows the configuration of Embodiment 3. In each unit, the smoothing capacitors C1 and C2 of the DC power supply units 6 and 7 obtained by rectification from a commercial power supply are connected in series via a power supply line 3b. The diodes D1 and D2 are connected to both DC power supply units 6,
7 are connected in such a manner that the polarities of the voltages of the smoothing capacitors C1 and C2 are aligned, and constitute a current loop communication circuit 12 that uses the sum of the voltages of the smoothing capacitors C1 and C2 connected in series as a power supply voltage. I have.

In the present embodiment, the first DC power supply unit 6 and the second DC power supply unit 7 provided in each unit
Are connected to the power supply voltage adjusting resistors R1 and R2, respectively, so that the voltage of the smoothing capacitors C1 and C2 becomes about の of the voltage required as the power supply of the current loop communication circuit.

As described above, in the present embodiment, the power supply voltage required as the DC power supply for the current loop communication circuit can be shared and held by the DC power supply units provided in both units. The withstand voltage of the electrolytic capacitors C1 and C2 in each DC power supply unit can be set smaller than in the first embodiment.

As a result, the first DC power supply 6 and the second DC power
The mounting area of the DC power supply unit 7 can be reduced, and the electronic control unit of each unit can be reduced in size.

(Fourth Embodiment) FIG. 6 shows a circuit configuration of a fourth embodiment. Second DC power supply unit 7 in indoor unit 1
, The voltage of the smoothing electrolytic capacitor C2 is divided by resistors R5 and R6.
A fourth photocoupler 14 operated by the control unit 15 is connected between the base terminals of the PN transistor 11.

Similarly, in the outdoor unit 2, an intermediate potential portion obtained by dividing the voltage of the smoothing electrolytic capacitor C1 in the DC power supply portion 6 by dividing resistors R3 and R4,
A second photocoupler 10 operated by the control unit 16 is provided between the P-type transistor 8 and a base terminal of the P-type transistor 8.

In the outdoor unit 2, the split resistors R3, R4
Adjusts the voltage peak value of the smoothing capacitor C1 in the DC power supply unit 6 by the voltage dividing ratio (R3 + R4) / (R1 + R3 + R4) of the combined resistance value R3 + R4 and the power supply voltage adjustment resistance R1, and sets the power supply voltage of the communication circuit. At the same time, the voltage applied to the voltage dividing resistor R3 with respect to the voltage of the smoothing capacitor C1 is adjusted by the voltage dividing ratio R3 / (R3 + R4), so that the voltage applied to both ends when the second photocoupler 10 serving as the opening / closing means is turned off. Can be adjusted.

Specifically, the voltage of the voltage dividing resistor R3 is
When the photocoupler 10 is off, the voltage of the smoothing capacitor C1 is divided by R3 and R4. On the other hand, when the second photocoupler 10 is turned on, the PNP transistor 8 serving as a switching element is turned on, so that the base resistor 21 is connected in parallel to R3, and the voltage across R3 is equal to the above-described voltage division. Lower than the value. Therefore, the voltage waveform across R3 is as shown in FIG.

In this embodiment, the second photocoupler 1
When the second photocoupler 10 is ON, the voltage across R3 is reduced by making the base resistor 21 and R3 approximately the same size so that the resistance voltage division ratio does not greatly change when ON / OFF of 0 is performed. And the voltage across R3 is set to be higher than the voltage at which the base current of the PNP transistor 8 can sufficiently flow.

In the present embodiment, similarly, in the indoor unit 1, the voltage shared by R5 is adjusted by the voltage dividing resistors R5 and R6 and the voltage adjusting resistor R2. The voltage of the DC power supply unit 2 is not used as the power supply voltage of the current loop communication circuit 12, and the voltage of C2 itself is not particularly limited. Therefore, it is also possible to omit the power supply voltage adjusting resistor R2 and configure the circuit only with the voltage dividing resistors R5 and R6.

As described above, by using the resistance dividing circuit of the smoothing capacitor potential instead of the constant voltage circuit using the constant voltage element, it is possible to configure the communication control device with a small number of parts and at low cost. .

(Fifth Embodiment) FIG. 8 shows a fifth embodiment. The fifth embodiment is an indoor / outdoor communication control device of an air conditioner that operates at 100 V AC and in which the indoor unit 2 is a power supply unit.

As shown in FIG. 8, a first DC power supply 6 is provided only in the outdoor unit 2, and a current loop communication circuit 12 using the first DC power supply 6 as a power supply is formed.

On the outdoor unit 2 side, the PNP transistor 8 is used as a transmission switch, and a constant voltage element 28 provided in the first DC power supply section 6 is connected between the base terminal of the PNP transistor 8 and the first DC power supply 6. , The second photocoupler 10 driven by the control unit 16 is connected.
As the second photocoupler 10, a photocoupler having a withstand voltage of 55 V or less is used.

On the other hand, the indoor unit 1 uses a high withstand voltage photocoupler 25 having a withstand voltage of 300 V as a transmission switch. Note that the present embodiment is a 100 VAC model, and the voltage applied to both ends of the coupler is 300 V or less even when the connection wires are erroneously connected. To 200
By connecting a ZNR from V to 300 V and setting the voltage applied to the coupler to 300 V or less, a photocoupler having a withstand voltage of 300 V can be used.

The high withstand voltage photocoupler 25 connects a resistor of about 100 kΩ between the base and the emitter terminal in order to shorten the OFF time at the time of switching.
By connecting the next side to the control unit 11 in the room, the current loop communication circuit 12 and the control unit 11 are insulated.

In this embodiment, the outdoor unit 2
Only the communication speed from the communication unit to the indoor unit 1 can be increased, and the opposite communication speed is the same as that of the conventional circuit. Also,
When only the communication from the indoor unit 1 to the outdoor unit 2 is to be speeded up, the first DC power supply unit 6 may be provided on the indoor unit 1 side. As described above, since the DC power supply unit is provided only in one unit, this embodiment has an advantage that the circuit configuration can be simplified.

Accordingly, in a case where high-speed communication with an external network is performed in an indoor unit using radio waves or the like, and only the transmission to the outdoor unit is to be communicated via the indoor / outdoor communication, the indoor / outdoor communication speed is limited in one direction. If you want to raise,
When the communication speed is not so much required, this method can realize a low-cost indoor / outdoor communication control device with a small number of components.

In the control device of the present embodiment, high-speed communication can be performed in one direction only by switching the communication speed for each communication direction. Control can be simplified by unifying the speed.

High-speed indoor / outdoor communication is performed only when necessary by switching the communication speed setting at high speed only when initial setting data is transmitted, when data obtained from an external network is transmitted, or when an abnormality occurs. It is also possible.

(Sixth Embodiment) FIG. 9 shows a sixth embodiment. Embodiments 1 to 3 have a demerit that power is consumed by the DC power supply unit in the power supply unit even during standby when the air conditioner is not operating, and so-called standby power consumption slightly increases. .

In order to solve this problem, in this embodiment, as shown in FIG. 9, the power supply to the outdoor unit 2 is turned on / off for the indoor unit 1 which is the power supply side unit.
The first opening / closing means 26 which performs FF, and the second opening / closing means 27 which is configured by a relay or a photocoupler for turning ON / OFF between the second DC power supply unit 7 and the commercial power supply 5 on the indoor unit 1 side. Is provided.

In the initial state when the power is turned on, both the first opening / closing means 26 and the second opening / closing means 27 are OFF. When the operation of the air conditioner is started, the first opening / closing means 26 is turned off.
Is turned on to energize the outdoor unit 2. Further, after turning on the second opening / closing means 27, indoor / outdoor communication is started.

As a result, in the standby state such as a remote control signal waiting state, the extra power consumed by the power supply voltage adjusting resistor R2 and the split resistors R5 and R6 in the second DC power supply unit 7 in the indoor unit 1 is not consumed, so High-speed indoor / outdoor communication can be performed without increasing the time power consumption.

The order of turning on the first opening / closing means 26 and the second opening / closing means 27 may be either first or simultaneous.

(Seventh Embodiment) FIG. 10 shows a seventh embodiment. A first power supply opening / closing means is provided in the indoor unit 1 for turning ON / OFF the power supply to the outdoor unit 2.
Opening / closing means 26.

The first opening / closing means 26 is constituted by a power relay, and is turned on by the control unit 15 in the power supply unit when the operation of the air conditioner is started.

Further, a timer means 30 is provided in the control unit 15 in the indoor unit 1 which is a power supply side unit, and effective transmission / reception is not performed even after a certain time has elapsed from the start of operation. Then, the first switching means 26, which is the power supply switching means, is turned off on the assumption that the connection wire is erroneously connected or the equipment is broken. FIG. 11 shows this flowchart.

As shown in the flowchart of FIG. 11, the transmission from the outdoor unit 2 to the indoor unit 1 and the reverse transmission from the indoor unit 1 to the outdoor unit 2 are combined into one sequence, and this one sequence is normally performed. If not, it is determined that valid transmission / reception has not been performed.

The reason for making such a determination is as follows. That is, one switching element, PNP
This is because, when the transistor 8 or the NPN transistor 11 is short-circuited, only one-way transmission is possible, and it is impossible to transmit in the reverse direction no matter how much time passes. By performing both transmission and reception as one sequence and determining whether communication is normal in sequence units, in the case of a communication abnormal state due to element destruction, it can be accurately determined that communication has never been correctly performed even once.

By performing the above control, the power-supplied unit is not connected to the power-supplied unit until the operation is started, or when the communication is not normally performed even if the time continues due to incorrect connection or breakage of the equipment. It is possible to cut off the power supply and to avoid unnecessary energization.

(Eighth Embodiment) A configuration and a flowchart of an eighth embodiment will be described with reference to FIGS. In general, when indoor / outdoor communication of an air conditioner is not established, there are cases where communication is completely impossible due to destruction of elements or incorrect connection,
It may be temporarily unsuccessful due to the influence of jamming radio waves. Some of these jamming waves are temporarily emitted, and in some cases communication is possible after a certain period of time.

Therefore, in the present embodiment, in consideration of the influence of such jamming waves and the like, if the effective transmission / reception is not performed even after a certain time T1 has elapsed by the timer means 30, the power supply opening / closing means is used. When a certain first opening / closing means 26 is once turned off, and further the timer means 30 is used to turn on the first opening / closing means 26 again after a lapse of time T2 which is a period sufficiently longer than T1, and communication is established. The operation shall be continued. If the communication is not established twice consecutively, it is determined that the communication is abnormal, the first opening / closing means 26 is turned off, and the power to the outdoor unit 2 is turned off.
Stop operation.

By performing such control,
When communication is not established due to disturbances such as jamming radio waves, the frequency of instantaneous shutdowns is reduced in the same way as when communication is not established due to erroneous connection or failure of equipment. Can be continued.

(Embodiment 9) FIG. 13 shows the configuration of Embodiment 9 of the present invention. As shown in FIG. 13, in the indoor unit 1 which is a unit on the power supply side, a connection point between the rectifying diode D1 of the DC power supply unit 6 and the commercial power supply connection line 3a and one line 5a of the commercial power supply 5 are connected. The first opening / closing means 26 is provided between them.

With this configuration, by turning off the first opening / closing means 26 composed of a power relay, power is supplied to the outdoor unit 2 and the DC power supply unit 6 in the indoor unit 1 is turned on.
Can be turned off all at once.

Therefore, according to the present embodiment, by using one opening / closing means, the same effect as in Embodiment 6 or Embodiment 8 can be realized, and a circuit can be configured with a smaller number of parts. It becomes possible.

[0080]

As is apparent from the above description of the present invention, according to the present invention, a DC power supply unit and a constant voltage circuit unit obtained by half-wave rectification are provided in the indoor and outdoor units, respectively, and the transmission switching element is provided. By newly providing a driving opening / closing means, indoor / outdoor communication at a higher speed than that of the conventional circuit can be performed.

Further, according to the present invention, the transmission switching element is an FET, so that the DC power supply section as a bias circuit can be easily designed, and the use of a high-speed coupler can further increase the speed of communication. Becomes

Further, according to the present invention, by connecting the rectifying and smoothing capacitors of each outdoor unit in series,
Since the DC voltage required for communication is shared indoors and outdoors, a capacitor with low withstand voltage can be used.As a result, it is possible to reduce the mounting space for the communication circuit corresponding to the DC power supply in each unit. Become.

Further, according to the present invention, the constant voltage circuit section is formed by dividing the resistance of the smoothing capacitor of the DC power supply section, so that the voltage of the DC power supply section can be adjusted by the resistance and the number of circuit components can be reduced. A low-cost communication circuit can be realized.

Further, according to the present invention, by providing a DC power supply unit in only one of the units, the components as a whole circuit are less expensive than the conventional circuit, but the communication is performed in only one direction. The speed can be improved to about 10 times.

According to the invention of the present application, the first opening / closing means for turning ON / OFF the power supply to the unit on the power supply side and the power supply to the DC power supply unit in the unit on the power supply side are turned ON.
N / OFF second opening / closing means is set to O
By performing FF, power consumption during standby can be reduced.

Further, according to the present invention, when there is an erroneous connection between the indoor unit and the outdoor unit during installation work or the like, the first opening / closing means is turned off by the timer means after a certain time has elapsed.
Then, by stopping the power supply, it is possible to stop the supply of power to unnecessary circuits.

Further, according to the present invention, when communication is not established for a certain period of time, the first opening / closing means is set to O once.
After the FF is performed and a predetermined period elapses, the first opening / closing means is turned on again and the communication is tried again. It is possible to continue the operation intermittently without stopping because of the failure of the vehicle.

Further, according to the present invention, by providing the first opening / closing means for simultaneously turning on / off the power supply to the power supply side unit and the power supply to the DC power supply unit in the power supply side unit, It is possible to simultaneously reduce the standby power consumption and cut off the energization when a communication error occurs.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an indoor / outdoor communication circuit of an air conditioner according to the present invention.

FIG. 2 is a diagram illustrating a configuration of a control data packet according to the first embodiment;

FIG. 3 is a flowchart showing a communication sequence according to the first embodiment;

FIG. 4 is a circuit diagram showing a configuration of a second embodiment.

FIG. 5 is a circuit diagram showing a configuration of a third embodiment.

FIG. 6 is a circuit diagram showing a configuration of a fourth embodiment.

FIG. 7 is a voltage waveform diagram of each part according to the fourth embodiment.

FIG. 8 is a circuit diagram showing a configuration of a fifth embodiment.

FIG. 9 is a circuit diagram showing a configuration of a sixth embodiment.

FIG. 10 is a circuit diagram showing a configuration of the seventh and seventh embodiments.

FIG. 11 is a flowchart of a seventh embodiment.

FIG. 12 is a flowchart of an eighth embodiment.

FIG. 13 is a circuit diagram showing a configuration of a ninth embodiment.

FIG. 14 is a circuit diagram showing an indoor / outdoor communication device in a conventional air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Indoor unit 2 Outdoor unit 3 Commercial power supply line 3a First line of commercial power supply line 3b Second line of commercial power supply line 4 Communication signal line 5 Commercial power supply 6 First DC power supply 7 Second DC Power supply unit 8 PNP transistor 9 First photocoupler 10 Second photocoupler 11 NPN transistor 12 Current loop communication circuit 13 Third photocoupler 14 Fourth photocoupler 15 Control unit (indoor unit side) 16 Control unit (Outdoor) 17) Current limiting resistor 18 Current limiting resistor 19 Protection diode (indoor unit side) 20 Protection diode (outdoor unit side) 21 Base resistance (indoor unit side) 22 Base resistance (outdoor unit side) 23 Base-emitter resistance 24 base -Emitter resistance 25 High voltage photocoupler 26 First switch Stage 27 Second switching means 28 First constant voltage element 29 Second constant voltage element 30 Timer means 31 P-channel MOSFET 32 N-channel MOSFET C1 Smoothing capacitor (in first DC power supply) C2 Smoothing capacitor (second D1 Rectifier diode (in the first DC power supply) D2 Rectifier diode (in the second DC power supply) R1 Power supply voltage adjustment resistor (in the first DC power supply) R2 Power supply voltage adjustment resistance (in the second DC power supply) R3 Divided resistance (in the first DC power supply) R4 Divided resistance (in the first DC power supply) R5 Divided resistance (in the second DC power supply) R6 Divided resistance (in the second DC power supply)

Claims (9)

[Claims] 1. A current loop is formed by a DC power supply obtained by half-wave rectification from a commercial power supply, and a plurality of switching elements and a current detection element connected in series. An indoor / outdoor communication control device for a separate type air conditioner for transmitting and receiving a digital signal between an indoor unit and an outdoor unit connected by a commercial power supply line and one communication signal line, wherein each unit of the air conditioner is Inside, a control unit for performing communication between the respective units is provided, and two DC power supply units obtained by half-wave rectification from a commercial power supply, respectively, each having a positive electrode side potential or each other. A first DC power supply unit and a second DC power supply unit having a negative potential as a common potential are provided in separate units of the air conditioner. In one unit, a PNP transistor having an emitter terminal connected to the potential on the positive side of the smoothing capacitor in the first DC power supply unit is provided, and in the unit, the PNP transistor is connected to the collector terminal of the PNP transistor. Is connected to a first photocoupler for detecting the collector current of
A second photocoupler, which is driven by the control unit in the unit and turns on / off a base current of the PNP transistor, is connected to a base terminal of the NP transistor, and an emitter terminal of the second photocoupler; A first constant voltage element set to be equal to or less than a withstand voltage of the second photocoupler is connected between the positive electrode side potential of the smoothing capacitor, and the first constant voltage element is connected to the same unit. The first DC power supply unit or the second DC power supply unit provided in
An NPN transistor having an emitter terminal connected to the negative electrode side potential of the smoothing capacitor in the DC power supply unit, and a third terminal for detecting a collector current of the NPN transistor at a collector terminal of the NPN transistor in the unit. Are connected, and the N
The base terminal of the PN transistor is connected to a fourth photocoupler which is driven by the control unit in the unit and turns on / off the base current of the NPN transistor. The collector terminal of the fourth photocoupler is connected to the fourth photocoupler. A second constant voltage element set to be equal to or lower than the withstand voltage of the fourth photocoupler is connected between the negative electrode side potential of the smoothing capacitor, and the second constant voltage element is provided in the same unit. The first DC power supply unit or the second DC power supply unit is used as a power supply, and the PNP transistor and the NPN transistor are turned ON / OFF by turning ON / OFF the second photocoupler and the fourth photocoupler. An indoor / outdoor communication control device for an air conditioner that conducts and shuts off the current flowing through the current loop. 2. The PNP transistor is a P-channel transistor.
The indoor / outdoor communication control device for an air conditioner according to claim 1, wherein the NPN transistor is an N-channel MOSFET. 3. The first DC power supply unit and the second DC power supply unit have one positive electrode and the other negative electrode connected through any one of the power supply lines, and are connected in series. The indoor / outdoor communication control device for an air conditioner according to claim 1 or 2, wherein a first DC power supply unit and a second DC power supply unit are used as a power supply for the current loop communication circuit. 4. In the first DC power supply unit and the second DC power supply unit, a voltage dividing resistor constituted by a plurality of resistors is connected to a smoothing capacitor in at least one of the DC power supply units. The indoor / outdoor communication control device for an air conditioner according to any one of claims 1 to 3, wherein a piezoresistor is used as a constant voltage element provided in the DC power supply unit. 5. A photocoupler as a substitute for the NPN transistor, wherein a first DC power supply is provided in the outdoor unit, and a second DC power supply and a fourth photocoupler are not provided in the indoor unit. 5. The indoor / outdoor communication control device for an air conditioner according to claim 1, wherein a photothyristor is used. 6. 6. A first opening / closing means for turning on / off the power supply to the power-supplied side unit and a second opening / closing means for turning on / off the power supply to the DC power supply unit in the unit on the power supply side. The first air conditioner when the operation of the air conditioner is stopped.
2. The first opening / closing means and the second opening / closing means are turned off.
5. The indoor / outdoor communication control device for an air conditioner according to any one of items 4 to 4. 7. A power supply side unit is energized by an operation signal of an air conditioner in a power supply side unit.
The indoor / outdoor communication of an air conditioner according to claim 5 or 6, further comprising a first opening / closing means for N / OFF and a timer means, wherein when the indoor / outdoor communication is not established for a predetermined time, the first opening / closing means is turned off. Control device. 8. A power supply side unit is energized by an operation signal of an air conditioner in a power supply side unit.
A first opening / closing means for N / OFF and a timer means are provided, and when communication inside and outside the room is not established for a certain time, the first supply opening / closing means is turned off once, and after the certain time has elapsed, the first opening / closing means is turned on again. The indoor / outdoor communication control device for an air conditioner according to claim 5 or 6, which is turned on. 9. An air conditioner, comprising: a first opening / closing means between a connection point between the DC power supply unit in the unit on the power supply side and one of the commercial power supply lines and one of the commercial power supply lines. When the operation of the power supply is stopped, or when communication between the inside and outside of the room is not established for a certain period of time, by turning off the first opening / closing means, the power supply to the power-supply-side unit is turned off, 9. The indoor / outdoor communication control device for an air conditioner according to claim 5, wherein power supply to the DC power supply unit is turned off simultaneously.