WO1999034152A1

WO1999034152A1 - Indoor-outdoor communication device in air conditioner

Info

Publication number: WO1999034152A1
Application number: PCT/JP1999/000002
Authority: WO
Inventors: Masaya Nishimura; Kunitoshi Hisaoka; Mitsuhiko Yamamoto; Akira Murai
Original assignee: Daikin Industries, Ltd.
Priority date: 1997-12-29
Filing date: 1999-01-04
Publication date: 1999-07-08
Also published as: EP1036995B1; EP1036995A1; DE69902511D1; EP1036995A4; CN1292077A; JP3399337B2; CN1116556C; DE69902511T2; ES2182477T3; JPH11193950A; ATE222343T1

Abstract

An air conditioner comprising one outdoor unit (1) and a plurality of indoor units (2) connected to the outdoor unit via three connection lines (3) including commercial power supply lines (3a, 3b) in parallel with each other, wherein the outdoor unit (1) includes an outdoor microcomputer (14), an outdoor dc power supply (11), an outdoor transmission photocoupler (15), an outdoor reception photocoupler (16) and a termination resistor (17) connected in parallel with the photocoupler (16), and each indoor unit (2) includes an indoor dc power supply (21), an indoor microcomputer (22), an indoor reception photocoupler (24) connected in parallel with the photocoupler (16), an indoor transmission photocoupler (23) and a positive temperature coefficient thermistor (25) connected in series with the photocoupler (23).

Description

TECHNICAL FIELD The present invention relates to an indoor / outdoor communication device in an air conditioner, and more specifically, to an outdoor unit via three connection lines including a commercial power supply line. The present invention relates to an indoor / outdoor communication device in an air conditioner to which an indoor unit is connected. BACKGROUND ART Conventionally, an air conditioner in which an indoor unit is connected to an outdoor unit via three indoor / outdoor connection lines including a commercial power supply line has been proposed. '

In such an air conditioner, installation of an outdoor unit, installation of an indoor unit, and wiring of three indoor / outdoor connection lines must be performed on site, so that incorrect wiring may always occur. If incorrect wiring occurs, not only will it be impossible to send and receive signals between the outdoor unit and the indoor unit normally, but also in some cases, it may cause damage to circuit elements, etc. for device satisfies is necessary to detect a _c such requests the occurrence of erroneous wiring before performing the normal operation, conventionally, when a predetermined time indoor-outdoor communication is not established, the power-off by the timer means Configuration to turn off the means

(See Japanese Patent Application Laid-Open No. Hei 6-147 6 16) A configuration in which a different voltage detection protection unit is provided to stop the operation of the transmission switch unit of the transmission / reception circuit unit (Japanese Patent Application Laid-Open No. Hei 8-27210 / 22) Gazette).

And, if these configurations are adopted, if miswiring occurs, air It is possible to prevent the inconvenience of operating the harmony device with erroneous wiring occurring.

However, when the configuration disclosed in Japanese Patent Application Laid-Open No. 6-147616 is adopted, a power supply switching means is specially required, and this power supply switching means is sufficient for a commercial power supply voltage. In addition, it is required to have a high withstand voltage, and since it is irrelevant during normal indoor / outdoor communication operation, it is inconvenient that it is difficult to keep the cost of the communication circuit unit low. Of course, during normal indoor / outdoor communication operation, a mounting area for mounting irrelevant power supply opening / closing means is required, so that it is difficult to achieve space saving in the communication circuit section.

Further, when the configuration disclosed in Japanese Patent Application Laid-Open No. Hei 8-27210 is adopted, a different voltage detection protection unit is specially required, and furthermore, as a component constituting this different voltage detection protection unit ^; It is necessary to use a device that has a sufficient withstand voltage with respect to the commercial power supply voltage, and it is irrelevant during normal indoor / outdoor communication operation. There is an inconvenience that it is difficult to keep it low. Of course, during normal indoor / outdoor communication operation, a mounting area for mounting an unrelated different voltage detection protection unit is required, and it is difficult to achieve space saving in the communication circuit unit. is there.

These problems also occur in a multi-type air conditioner in which a plurality of indoor units are connected in parallel to one outdoor unit via three connection lines including a commercial power line. Occurs similarly.

The present invention has been made in view of the above-described problems, and does not require an extraneous circuit configuration during normal indoor / outdoor communication operation, such as a power supply switching means, a different voltage detection protection unit, etc. Even if it occurs, it is possible to prevent the occurrence of inconveniences such as destruction of transmission / reception circuit components and disconnection. An indoor / outdoor communication device for an air conditioner according to claim 1 is provided with three connection lines including a commercial power line for an outdoor unit. Air conditioner that connects indoor units via

One of the outdoor unit and the indoor unit

A first control means, a first power supply means for supplying power to the first control means, and a first control means for transmitting and receiving signals to and from the commercial AC power supply via a DC power supply means. A first transmitting photocoupler, a first receiving photobra, and a first resistance means connected in parallel with the first receiving photobra;

The indoor unit, the other of the indoor units

A second receiving photo-signal transmitting / receiving signal between the second control means and the second controlling means and connected in parallel with the first receiving photo-coupler via two of the three connection lines. Power brass, a second transmitting photo brass, and a second resistance means connected in series with the second transmitting photo brassier to suppress overcurrent at the time of incorrect wiring.

The indoor / outdoor communication device in the air conditioner according to claim 2 is configured such that a plurality of indoor units are connected in parallel to one outdoor unit via three connection lines including a commercial power supply line. In an air conditioner

The outdoor unit transmits and receives signals between the outdoor control means, the outdoor control power supply means for supplying power to the outdoor control means, and the DC power supply means between the terminals of the commercial AC power supply. An outdoor transmission photobra, an outdoor reception photobra, and an outdoor reception photobra connected in series with each other via And a first resistance means connected in parallel with the

Each indoor unit has an indoor control power supply connected to a terminal of a commercial AC power supply via a commercial power supply line, an indoor control power supplied by the indoor control power supply, and an indoor control. Means for transmitting and receiving signals to and from the vehicle, and a photobra for indoor reception and a photobra for indoor transmission connected in parallel with the outdoor reception photocabler via two of the three connection lines. And a second resistance means connected in series with the indoor transmission photocoupler for suppressing an overcurrent at the time of erroneous wiring.

The room / indoor / outside communication device in the air conditioner according to claim 3 employs a positive temperature characteristic thermistor as the second resistance means.

An indoor / outdoor communication device in the air conditioner according to claim 4, wherein the indoor unit is connected to the outdoor unit via three connection lines including a commercial power supply line;

One of the outdoor unit and the indoor unit

An outdoor control means, an outdoor control power supply means for supplying power to the outdoor control means, and a signal exchange between the outdoor control means and a DC power supply means between the terminals of the commercial AC power supply. An outdoor transmitting photopower bra, an outdoor receiving photopower bra connected in series with each other, and a first resistance means connected in parallel with the outdoor receiving photopower bra;

The other of the outdoor unit and the indoor unit

A transformer connected to a terminal of a commercial AC power supply via a commercial power supply line, rectifying means for converting an output voltage from the transformer into a DC voltage, and different voltage detecting means operating based on the converted DC voltage; A second power supply means connected between the output terminals of the rectifying means, a room control means to which the converted DC voltage is applied, and a signal transmission / reception between the room control means and three connection lines. Connected in parallel with the outdoor reception And a second resistance means connected in series with the indoor transmission photo power blur.

The indoor / outdoor communication device in the air conditioner according to claim 5 is configured such that a plurality of indoor units are connected in parallel to one outdoor unit via three connection lines including a commercial power supply line. In an air conditioner

The outdoor unit transmits and receives signals between the outdoor control means, the outdoor control power supply means, and the outdoor control means, and is connected in series between the terminals of the commercial AC power supply via the DC power supply means for outdoor transmission. A photocoupler, a photobra for outdoor reception, and first resistance means connected in parallel with the photocabra for outdoor reception,

Each indoor unit has a transformer connected to a terminal of a commercial AC power supply via a commercial power supply line, rectifying means for converting an output voltage from the transformer into a DC voltage, and operates based on the converted DC voltage. Signal between the different voltage detector, the indoor control power supply connected between the output terminals of the rectifier, the indoor controller to which the converted DC voltage is applied, and the indoor controller. And a photocoupler for indoor reception, a photobra for indoor transmission, and a photocoupler for indoor transmission connected in series with the outdoor reception photocabler via two of the three connection lines. This includes a second resistance means.

In the case of the indoor / outdoor communication device in the air conditioner according to claim 1, the indoor unit is connected to the outdoor unit via three connection lines including a commercial power supply line, and the outdoor unit and the indoor unit are connected to each other. In order to operate the air conditioner while transmitting and receiving signals, the AC power is supplied from the commercial AC power supply to either the outdoor unit or the indoor unit, and the outdoor unit or indoor unit is connected via the commercial power line. Supply power to the other machine. Then, the communication signal from the first control means is received by the second receiving photo cover via the first transmitting photo cover, and the second receiving photo cover is received. The signal received by the photocabler is supplied to the second control means to control the other of the outdoor unit and the indoor unit. Further, the communication signal from the second control means is received by the first reception photo-coupler via the second transmission photo-focuser, and the signal received by the first reception photo-brabler is supplied to the first control means. It monitors the status of the other of the outdoor unit and the indoor unit.

In addition, the outdoor unit and the indoor unit are installed, and immediately after the three units are connected to each other, the respective control means are operated so that signals can be exchanged between the outdoor unit and the indoor unit. If the three connection lines are connected properly, the normal signal transmission and reception will be performed. Conversely, if the three connection lines are not correctly connected, the normal signal transmission and reception will be performed. Since it is not performed, it is possible to detect whether or not the connection of the three connection lines is normal.

Therefore, the operation state of the second transmission photocoupler is forcibly set, and at the time of erroneous wiring, the current is limited by the second resistance means that suppresses overcurrent. In addition, it is possible to prevent the occurrence of inconveniences, such as disconnection, disconnection, etc., and to improve the communication speed by using a DC power supply for communication power supply. Since no circuit components irrelevant to signal transmission and reception, such as components, are not required at all, it is possible to prevent cost increase and increase in mounting area.

In the case of the indoor / outdoor communication device in the air conditioner of claim 2, a plurality of indoor units are connected in parallel to one outdoor unit via three connection lines including a commercial power line. In order to operate the air conditioner while exchanging signals between the outdoor unit and the indoor unit, AC power is supplied from a commercial AC power supply to the outdoor unit, and each indoor unit is connected via a commercial power line. AC power is supplied to the indoor control power supply means. Then, the communication signal from the outdoor control means is transmitted to the indoor unit through the outdoor transmission photo cover. The signal is received by a bra and the received signal from the indoor reception photocabler is supplied to the indoor control means to control the indoor unit. In addition, the communication signal from the indoor control means is received by the outdoor receiving photocabler of the outdoor unit via the indoor transmitting photocabler, and the signal received by the outdoor receiving photocabler is supplied to the outdoor control means to be transmitted to the indoor control means. Monitor the status of the machine.

Also, an outdoor unit and multiple indoor units are installed, and each control is performed so that signals can be exchanged between the outdoor unit and the indoor unit immediately after these units are connected using three connection lines. By operating the means, a normal signal is sent and received when the three connection lines are connected properly, and conversely, when the three connection lines are not connected properly, Since signals are not exchanged, it is possible to detect whether or not the connection of the three connection lines is normal.

Therefore, the operating state of the indoor transmission photocoupler is forcibly set, and the current is limited by the second resistance means that suppresses overcurrent in the case of incorrect wiring. The occurrence of inconveniences such as disconnection can be prevented beforehand, and the communication speed can be improved by using a DC power supply for communication.In addition, power supply switching means and different voltage detection protection unit Since no circuit components unrelated to signal transmission and reception are not required at all, the cost can be prevented and the mounting area can be prevented from increasing.

In the case of the indoor / outdoor communication device in the air conditioner of claim 3, since a positive temperature characteristic thermistor is employed as the second resistance means, the effect of suppressing the current at the time of incorrect wiring can be enhanced. The same operation as in claim 2 can be achieved.

In the case of the indoor / outdoor communication device in the air conditioner according to claim 4, the other of the outdoor unit and the indoor unit is connected to one of the outdoor unit and the indoor unit via three connection lines including a commercial power supply line. To send and receive signals between the outdoor unit and the indoor unit. To operate the air conditioner while supplying AC power from a commercial AC power supply to one of the outdoor unit and the indoor unit, the second unit of the outdoor unit and the indoor unit via the commercial power supply line and transformer Supply AC power to the power supply means. Then, the communication signal from the first control means is received by the second receiving photopower blur of the outdoor unit and the indoor unit via the first transmitting photopower blur, and the second receiving photopower blur is received by the second receiving photopower blur. The received signal is supplied to the second control means to control the other of the outdoor unit and the indoor unit. Also, the communication signal from the second control means is received by the first receiving photocoupler of the outdoor unit or the indoor unit via the second transmitting photocabler, and the signal received by the first receiving photocabler is received by the first transmitting photocabler. 1 Supply to the control means to monitor the other state of the outdoor unit and the indoor unit.

In addition, the outdoor unit and the indoor unit are installed, and immediately after the three units are connected to each other, the respective control means are operated so that signals can be exchanged between the outdoor unit and the indoor unit. For example, when three connection lines are connected properly, a normal signal is transmitted and received. Conversely, when three connection lines are not connected properly, a normal signal is transmitted and received. Since it is not connected, it is possible to detect whether or not the connection of the three connecting wires is normal. Then, in the case of incorrect wiring, a normal voltage is not generated at the output side of the transformer due to the formation of a current loop passing through the first resistance means. Can be recognized.

Therefore, it is possible to prevent the occurrence of inconveniences such as destruction and disconnection of transmission / reception circuit components due to incorrect wiring, and to improve the communication speed by using a DC power supply for communication. In addition, since there is no need for circuit components unrelated to signal transmission and reception such as power supply switching means and different voltage detection protection section, it is possible to prevent cost increase and increase mounting area.

In the case of the indoor / outdoor communication device in the air conditioner of claim 5, one room Multiple indoor units are connected in parallel to the outdoor unit via three connection lines including the commercial power line, and the air conditioner transmits and receives signals between the outdoor unit and the indoor unit. In operating the, the AC power is supplied from the commercial AC power supply to the outdoor unit, and the AC power is supplied to the indoor control power supply means of each indoor unit via the commercial power supply line and the transformer. Then, the communication signal from the outdoor control means is received by the indoor reception photocabler of the indoor unit via the outdoor transmission photocabler, and the reception signal by the indoor reception photocabler is supplied to the indoor control means to receive the signal. Control the machine. In addition, the communication signal from the indoor control means is received by the outdoor receiving photo power blur of the outdoor unit via the indoor transmitting photo cover, and the reception signal by the outdoor receiving photo power blur is supplied to the outdoor control means. To monitor the state of the indoor unit.

In addition, an outdoor unit and a plurality of indoor units are installed, and these control units are connected to each other using three connection lines, and then control signals are transmitted and received between the outdoor unit and the indoor unit. By operating the, the normal signal transmission / reception is performed when the three connection lines are connected properly, and the normal signal is transmitted when the three connection lines are not connected properly. Is not performed, it is possible to detect whether or not the connection of the three connection lines is normal. Then, at the time of erroneous wiring, since a normal voltage is not generated on the output side of the transformer due to the formation of a current loop passing through the first resistance means, this state is detected by the different voltage detection means, and The type of wiring can be recognized.

Therefore, it is possible to prevent the occurrence of inconveniences such as destruction and disconnection of transmission / reception circuit components due to incorrect wiring, and to improve the communication speed by using a DC power supply for communication. In addition, since there is no need for circuit components unrelated to signal transmission / reception such as power supply switching means and different voltage detection protection section, it is possible to prevent cost increase and increase in mounting area. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an electric circuit diagram showing one embodiment of an indoor / outdoor communication device in an air conditioner of the present invention.

FIG. 2 is a flowchart illustrating the process of determining the incorrect wiring of the indoor unit _c . FIG. 3 is a flowchart illustrating the process of determining the incorrect wiring of the outdoor unit _c . FIG. 4 is a signal waveform diagram for explaining the incorrect wiring determination timing.

FIG. 5 is a signal waveform diagram showing communication from the outdoor unit to the indoor unit when no miswiring occurs.

FIG. 6 is a signal waveform diagram showing extra communication from the indoor unit 1 to the outdoor unit and the indoor unit 2 when no miswiring occurs.

FIG. 7 is a signal waveform diagram illustrating the operation of indoor and outdoor communication data and communication signal lines when no miswiring occurs.

FIG. 8 is a schematic diagram illustrating a miswiring pattern when an outdoor unit and one indoor unit are present.

FIG. 9 is a schematic diagram illustrating a miswiring pattern when an outdoor unit and two indoor units are present.

FIG. 10 is a diagram showing a state in which the commercial power supply line 3a and the signal line 3c are incorrectly wired.

FIG. 11 is a diagram showing a state in which the commercial power supply line 3b and the signal line 3c are incorrectly wired.

FIG. 12 is a diagram showing a state in which the commercial power lines 3a and 3b are incorrectly wired.

Fig. 13 shows that the commercial power line 3a is the signal line 3c and the signal line 3c is the commercial line. FIG. 4 is a diagram showing a state in which the power supply line for use 3b and the commercial power supply line 3b are miswired with the commercial power supply line 3a.

Fig. 14 shows the situation where the commercial power line 3a is miswired with the commercial power line 3b, the signal line 3c with the commercial power line 3a, and the commercial power line 3b with the signal line 3c. FIG.

FIG. 15 is an electric circuit diagram showing another embodiment of the indoor / outdoor communication device in the air conditioner of the present invention.

FIG. 16 is a flowchart for explaining an incorrect wiring determination process for an indoor unit. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of an indoor / outdoor communication device in an air conditioner of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an electric circuit diagram showing an embodiment of an indoor / outdoor communication device in the air conditioner of the present invention.

This air conditioner has one outdoor unit 1 and a plurality of indoor units 2. The plurality of indoor units 2 are connected in parallel to the outdoor unit 1 via three connection lines 3.

The outdoor unit 1 includes a half-wave rectified DC power supply circuit (DC power supply means) 12 connected between terminals of a commercial AC power supply 10, and an outdoor control power supply connected between terminals of the commercial AC power supply 10. DC power supply 11 for outdoor control as means, outdoor microcomputer 14 as control means for outdoor, outdoor transmission photocoupler 15 connected to the transmission port of outdoor microcomputer 14, and outdoor A photobra 16 for outdoor reception connected to the reception port of the microcomputer 14 and a terminator as the first resistance means connected in parallel with the photobra 16 for outdoor reception Yon resistance 1 7 {This resistance is used to make the impedance of the communication line constant and take measures against malfunctions caused by the stray capacitance of the wiring cable (communication line) connecting the indoor unit and the outdoor unit, which is necessary for normal communication. Which is a high resistance. Then, the light-receiving element 1 _5b of the outdoor transmission photocoupler 15, the first diode 18 a., And the third resistor (in the case of incorrect wiring, a sufficient current limit for the light-receiving element 15 b of the outdoor transmission photocoupler 15 is required. 18b, 2nd diode 18c, 4th resistor (for outdoor reception in case of incorrect wiring) A resistor having a resistance value that can limit the current enough to prevent destruction of the light emitting element 16a of the photocoupler 16 and can achieve communication by the light emitting element 16a of the outdoor receiving photocoupler 16). 18 d, outdoor receiving photocoupler 16 Light emitting element 16 a of 16 and Zener diode 18 e are connected in series, and this series connection circuit is connected in parallel with the smoothing circuit section of half-wave rectified DC power supply circuit 12. ing. The collector terminal of the transistor 15c is connected in series with the light emitting element 15a of the outdoor transmission photocoupler 15 and the emitter terminal of the transistor 15c is grounded. A resistor 15d is connected between the base terminal of the transistor 15c and the emitter terminal, and a resistor 15e is connected between the base terminal of the transistor 15c and the transmission port of the outdoor microcomputer 14. In addition, 15 f is a resistor connected between the output terminal of the outdoor control DC power supply 11 and the light emitting element 15 a of the outdoor transmission photocoupler 15. The emitter terminal of the light receiving element 16b of the outdoor reception photocoupler 16 is grounded via the resistor 16c, and the connection point between the emitter terminal of the light receiving element 16b and the resistor 16c is connected to the outdoor microcomputer. 14 Connected to receiving port 4. A digital transistor can be used instead of the electric circuit composed of the transistor 15c and the resistors 15d and 15e, and the polarity can be set according to a signal to be output. Possible It is.

The three indoor / outdoor connection lines 3 include a pair of commercial power lines 3a and 3b and a communication signal line 3c, and the pair of commercial power lines 3a and 3b are used for commercial purposes. Connected to both terminals of the AC power supply 10, one communication signal line 3c is connected to a connection point between the third resistor 18b and the second diode 18c.

The indoor unit 2 includes a control DC power supply 21 as an indoor control power supply connected between a pair of commercial power supply lines 3a and 3b, and an indoor microcomputer 2 as an indoor control means. 2, an indoor photocoupler 23 connected to the transmission port of the indoor microcomputer 22, a photocoupler 24 for indoor reception connected to the reception port of the indoor microcomputer 22, and a photocoupler for indoor transmission. Tokabura 2 3 follower being phototransistor 2 3 b series connected to the collector terminal of the first having a positive temperature ^coefficient; and a second positive temperature characteristic thermistor 2 5 overcurrent protection as a resistance means. The third diode 26a and the fifth resistor (current can be limited to a degree that can prevent the destruction of the light emitting element 24a of the indoor receiving photocoupler 24 in the case of incorrect wiring, and the indoor receiving photocoupler 24 26 b, the light-emitting element 24 a of the indoor receiving photocoupler 24 and the Zener diode 26 c are connected in series. It is connected in parallel with the termination resistor 17 via a commercial power supply line 3b and a communication signal line 3c. The series connection circuit of the positive temperature characteristic thermistor 25 and the light receiving element 23 b of the indoor transmission photocoupler 23 is connected to the fifth resistor 26 b, the light emitting element 24 a of the indoor reception photocoupler 24, and the Zener diode. It is connected in parallel with the series connection circuit of IDC 26c. Further, the cathode terminal of the light-emitting element 23a of the indoor transmission photopower bracket 23 is grounded via the resistor 23c, and the anode terminal of the light-emitting element 23a is connected to the transistor 23d. Connected to the collector terminal, a resistor 23e is connected between the emitter terminal and the base terminal of this transistor 23d, and the base terminal of the transistor 23d is connected to the indoor microcomputer via the resistor 23f. it is connected to your 2 second transmission port _{Note, 2 3 g are Burua' up resistor connected to the microcomputer 2 second transmission port for the room. Furthermore, the emitter terminal of the photodetector 24 b of the photoreceiver for indoor reception 24 is grounded via a resistor 24 c, and the emitter terminal of the photodetector 24 b is connected to the resistor 2. The connection point with 4c is connected to the reception port of the indoor microcomputer 22. It is possible to use a digital transistor instead of the electric circuit composed of the transistor 23c and the resistor 23d.23e, and to set the polarity according to the signal to be output. is there. Further, the positive temperature characteristic thermistor .25 has a function of protecting the switching overcurrent of the light receiving element 23b of the indoor transmission photocoupler 23 during the normal communication operation.

FIG. 2 is a flowchart illustrating the process of determining an incorrect wiring of an indoor unit. In step SP1, set the transmission port of the indoor microcomputer 22 to ON.

(The light-receiving element 23 b of the indoor transmission photobra 23 is set to OFF), and in step SP2, the judgment of the commercial power supply frequency interrupt is performed. If it is determined that there is a commercial power frequency interrupt, in step SP3 it is recognized that the connection of the indoor / outdoor connection line 3 is abnormal, and in step SP4, the indoor microcomputer 2 2 Turn off the transmission port (turn on the light-receiving element 23 b of the indoor transmission photocoupler 23), and end the series of processing.

Conversely, if it is determined in step SP2 that there is no commercial power frequency interrupt, in step SP5 it is recognized that the connection of the indoor / outdoor connection line 3 is normal, and in step SP6, the normal Perform the operation based on the sequence. FIG. 3 is a flowchart for explaining an incorrect wiring determination process of the outdoor unit. In step SP1, the transmission port of the outdoor microcomputer 14 is turned off (the light-receiving element 15b of the outdoor transmission photobra 15 is turned off), and in step SP2, the reception data interrupt is determined. . Then, when it is determined that there is a reception data interrupt, in step SP8, it is recognized that the connection of the indoor / outdoor connection line 3 is abnormal, and the process of the replay step SP1 is performed. Conversely, if it is determined in step SP2 that there is no reception data interrupt, in step SP3, wait processing is performed until the erroneous wiring determination period of the indoor unit 2 elapses, and in step SP4, the outdoor processing is performed. The transmission port of the microcomputer 14 is turned on (the light receiving element 15b of the outdoor transmission photocoupler 15 is turned on), and in step SP5, it is determined whether or not the transmission output and the reception input are equal to each other. . Then, when the transmission output and the reception input are not equal to each other, the processing of step SP8 is performed. Conversely, if it is determined in step SP5 that the transmission output and the reception input are equal to each other, it is recognized in step SP6 that the connection of the indoor / outdoor connection line 3 is normal, and in step SP7, The operation is performed based on the normal sequence.

FIG. 4 is a signal waveform diagram for explaining an incorrect wiring determination timing at power-on.

When the power is turned on as shown in (A) in Fig. 4 and the reset is performed as shown in (B) in Fig. 4, as shown in (C) and (D) in Fig. 4, , Both the outdoor transmission output and the outdoor reception input go low,

(E) As shown in (F), the indoor transmission output becomes high level and the indoor reception input becomes mouthful level.

Then, in the first period after the reset (interruption determination period in FIG. 4), the reception data interruption determination in step SP2 of the flowchart in FIG. 3 is performed. In the subsequent second period (the indoor unit determination period Wait in FIG. 4), the wait process in step SP3 of the flowchart in FIG. 3 is performed, and the subsequent third period (in FIG. During the input / output match determination period), the input / output match determination in step SP5 of the flowchart in FIG. 3 is performed, and it can be determined whether the connection of the indoor / outdoor connection line 3 is normal.

Further, a fourth period after the reset (a period longer than the first period and shorter than the total period of the first period and the second period described above). In the determination period), the determination of the commercial power supply frequency interrupt in step SP2 of the flowchart of FIG. 2 is performed.

In FIG. 4, the signal waveform in the case where an erroneous wiring occurs is indicated by a broken line.

This will be described in more detail.

After the power is turned on, the photodetector 15b of the outdoor transmission photocoupler 15 that is responsible for generating the outdoor unit transmission signal is turned off, and any pulse signal is output to the outdoor unit even though the outdoor unit is not supplying power for communication. If the receiving circuit of the outdoor unit receives the signal, the outdoor unit determines that the wiring is incorrect, and keeps the light receiving element 15b of the outdoor transmission photocoupler 15 OFF and keeps the communication circuit element from the incorrect wiring state. Protect.

Also, when a pulse of the commercial power frequency is detected by the indoor unit receiving circuit based on the input of the receiving circuit, the light receiving element 23 of the indoor transmission photo power blur 23 and the light receiving element of the outdoor transmission photo coupler 15 are changed. By turning it on in reverse to 15b and shorting the communication signal line 3c and one of the commercial power lines, even if the outdoor unit transmits data without knowing that the indoor unit is miswired, Protects the voltage exceeding the breakdown voltage of the photocabler from being applied to the photodetector 23 b of the indoor transmission photocoupler 23. In addition, this pattern causes a short circuit between the commercial power lines in a pattern with miswiring. However, in order to prevent damage to the transmission / reception circuit of the indoor unit even if the commercial power supply line is short-circuited, it is necessary to limit the communication current and damping in series with the light receiving element 23 b of the indoor photocoupler 23. Introduce a positive temperature characteristic thermistor 25 for current protection, and if it is short-circuited, the self-heating of the positive temperature characteristic thermistor 25 will cause a rapid increase in the resistance value, thereby suppressing the short-circuit current and indoor transmission The light receiving element 23 b of the trusted photocoupler 23 is protected.

Although not shown in Fig. 4, if the microcomputer is configured to be able to reset itself using the watchdog timer, automatic recovery is possible even if the microcomputer runs out of control due to incorrect wiring. Yes, communication circuits can be protected before they are destroyed.

FIG. 5 is a signal waveform diagram showing an example of communication from the outdoor unit to the indoor unit when no miswiring occurs. In Fig. 5, (A) (B) (C)

(D), (E), and (F) i show the outdoor transmission waveform, the outdoor reception waveform, the indoor 1 transmission waveform, the indoor 1 reception waveform, the indoor 2 transmission waveform, and the indoor 2 reception waveform, respectively. However, the actual communication waveform is not always the waveform shown in Fig. 5, because it is determined by the communication rules between the outdoor unit and the indoor unit.

In this case, after the outdoor transmission waveform is turned ON for a predetermined time from OFF, it is turned OFF-ON according to the transmission signal. The light emitting element 15a of the outdoor transmission photocoupler 15 is controlled by an electric circuit composed of a transistor 15c, resistors 15d and 15e, and the outdoor reception photocoupler 16 The reception signal extraction terminal from the light receiving element 16b and the reception signal extraction terminal from the light receiving element 24b of the indoor reception photocoupler 24 are set as shown in the figure, so that the outdoor reception waveform is the same as the outdoor transmission waveform. As a result, the indoor 1 receive waveform and the indoor 2 receive waveform become the same as the outdoor transmit waveform. Since the indoor unit 1 and the indoor unit 2 do not transmit the signal, both the indoor 1 transmission waveform and the indoor 2 transmission waveform remain ON. FIG. 6 is a signal waveform diagram showing an example of communication from the indoor unit 1 to the outdoor unit and the indoor unit 2 when no miswiring occurs. In Fig. 6,

(B), (C), (D), (E), and (F) show the outdoor transmission waveform, the outdoor reception waveform, the indoor one transmission waveform, the indoor one reception waveform, the indoor two transmission waveform, and the indoor two reception waveform, respectively. However, the actual communication waveform is not always the waveform shown in Fig. 6, since it is determined by the rules for communication between outdoor units and indoor units. In this case, after one indoor transmission waveform continues to be ON for a predetermined time, OFF-ON is performed in accordance with the transmission signal. It is controlled by an electric circuit composed of the light emitting element 23a of the indoor transmission photocoupler 23, the transistor 23c, the resistors 23d, and 23e, and the outdoor reception photobrush. The reception signal extraction terminal from the light receiving element 16b of 16 and the reception signal extraction terminal from the light receiving element 24b of the photoreceiver for indoor reception 24 are set as shown in the figure. The 1st indoor transmission waveform is the same as the 1st indoor transmission waveform and the 2nd indoor reception waveform is the same as the 1st indoor transmission waveform. Since the outdoor unit and the indoor unit 2 do not transmit signals, both the outdoor transmission waveform and the indoor 2 transmission waveform remain ON.

FIG. 7 is a signal waveform diagram illustrating an example of indoor / outdoor communication data and communication signal line operation when no miswiring occurs. In FIG. 7, (A), (B), (C), (D), and (E) show the outdoor transmission waveform, the outdoor reception waveform, the communication line waveform, the indoor one transmission waveform, and the indoor one reception waveform, respectively. However, the actual communication waveform is not always the waveform shown in Fig. 7, since it is determined by the communication rules between the outdoor unit and the indoor unit.

In this case, after the outdoor transmission waveform is turned ON for a predetermined time from OFF, the data is transmitted by performing OFF-ON in accordance with the transmission signal. Then, it is assumed that the light-emitting element 23a of the indoor transmission photopower bracket 23 is controlled by an electric circuit composed of a transistor 23c, resistors 23d, and 23e. In both cases, the reception signal extraction terminal from the light receiving element 16b of the outdoor reception photocoupler 16 is set as shown in the figure, so the outdoor reception waveform is the same as the outdoor transmission waveform, and the transmission data is monitored. be able to. Of course, this data is supplied to the indoor unit 1 through the signal line 3c, and the receiving signal extraction terminal from the light receiving element 24b of the indoor receiving photo cover 24 is set as shown in the figure. The communication line waveform and the indoor 1 receive waveform are the same as the outdoor transmit waveform. Then, since indoor unit 1 does not transmit a signal, indoor 1 transmission waveform remains ON.

After the data transmission from the outdoor unit to the indoor unit 1 has been performed as described above, the indoor 1 transmission waveform is turned OFF in accordance with the transmission signal to transmit the data. The light-emitting element 23a of the indoor transmission photobra 23 is controlled by an electric circuit composed of a transistor 23c, resistors 23d, and 23e (in-room photocoupler). Since the reception signal extraction terminals of the 24 light receiving elements 24b are set as shown in the figure, the reception waveform in one room is the same as the transmission waveform in one room, and the transmission data can be monitored. This data is supplied to the outdoor unit through the signal line 3c, and the receiving signal extraction terminal from the light receiving element 16b of the outdoor receiving photocoupler 16 is set as shown in the figure. The communication line waveform and the outdoor reception waveform are the same as the indoor 1 transmission waveform, and the outdoor transmission waveform remains ON because no signal is sent from the outdoor unit.

Next, the miswiring patterns are shown in (A), (B), (C), (D) and (E) in FIG. 8 and (AA) (AB) (AC) (AD) (AE) in FIG. FIG. 8 shows a case where an outdoor unit and one indoor unit are present, and FIG. 9 shows a case where an outdoor unit and two indoor units are present. In addition, (AA) (AB) (AC) (AD) (AE) in Fig. 9 indicates that incorrect wiring of the pattern shown in (A) in Fig. 8 occurs between the outdoor unit and the first indoor unit. In Fig. 8 (A), (B), and (C)

(D) shows a state in which erroneous wiring of the pattern shown in (E) has occurred, that is, a state in which the above erroneous wiring patterns are combined. Therefore, the miswiring pattern in FIG. 9 is basically the same as the miswiring pattern in FIG. Then, even if the number of erroneously wired indoor units increases, the erroneous wiring pattern is basically the same as the erroneous wiring pattern in FIG.

Next, as shown in (A), (B), (C), (D), and (E) in FIG. 8, the operation when an incorrect wiring occurs will be described in detail with reference to FIGS. 10 to 14. explain.

In FIG. 10, the third diode 26a, the fifth resistor 26b, the light-emitting element 2a of the indoor reception photopower 24 and the Zener die are connected between the output terminals of the commercial AC power supply 10. Since the circuit 26c is connected in series, a current flows as shown by an arrow A1 in FIG. 10 every half cycle of the commercial AC power supply 10. In this case, since the indoor control DC power supply 21 is cut off from the commercial AC power supply 10, no operation power is supplied to the indoor microcomputer 22. 2 2 does not work. Also, in this case, the current flows directly to the light emitting element 24a of the photoreceiver 24 for indoor reception, but the light emitting element 24a is destroyed because the fifth resistor 26b is connected in series. The inconvenience of being done does not occur. Further, in this case, since the signal from the indoor unit 2 is not supplied to the outdoor unit 1, in the outdoor unit 1, miswiring is performed based on the time-out after the signal is transmitted. Can be detected.

FIG. 11 is a diagram showing a state in which the commercial power line 3b and the signal line 3c are incorrectly wired. In FIG. 11, in the half cycle of the commercial AC power supply 10, as indicated by an arrow A 1, the current passes through the control DC power supply 21 of the indoor unit 2, passes through the second diode 18 c, and the fourth resistor 18 d An electric current flows through a series connection circuit of the light receiving element 16a and the Zener diode 18e of the outdoor reception photocoupler 16 and a termination resistor 17 connected in parallel with this series connection circuit. A receive data interrupt occurs for microcomputer 14. In the other half cycle of the commercial AC power supply 10, as indicated by the arrow A2, the third diode 26a, the fifth resistor 26b, and the light-emitting element 24 A current flows through a series connection circuit of a and a zener diode 26 c and a termination resistor 17 connected in parallel with the series connection circuit, and furthermore, the control DC power supply 21 of the indoor unit 2 is turned on. Electric current flows through it. As a result, since the control DC power supply 21 of the indoor unit 2 rises, the indoor microcomputer 22 also rises and a commercial power frequency interrupt to the room microcomputer 22 can be detected. Therefore, it is possible to detect the occurrence of erroneous wiring by the processing of the flowchart of FIG. 2 and the processing of the flowchart of FIG. In this case, the fifth resistor 26 b is connected in series with the light emitting element 24 a of the indoor receiving photocoupler 24, and the commercial power supply is connected via the control DC power supply 21. Since the light is supplied to the series connection circuit, there is no inconvenience that the light emitting element 24a is destroyed, and further, the light emitting element 16a of the outdoor reception photopower bra 16 is connected in series with the light emitting element 16a. 4 A resistor 18 d is connected, and a termination resistor 17 is connected in parallel with the light-emitting element 16 a of the outdoor reception photo cover 16, but the commercial power supply controls these circuits. Since the power is supplied via the direct-current power supply 21, there is no disadvantage that the light emitting element 16a is destroyed.

FIG. 12 is a diagram showing a state in which the commercial power lines 3a and 3b are incorrectly wired. In FIG. 12, in the half cycle of the commercial AC power supply 10, a current flows only through the control DC power supply 21 of the indoor unit 2 as indicated by an arrow A1. In the other half cycle of the commercial AC power supply 10, as shown by an arrow A2, a termination resistor 17, a third diode 26a, and a fifth resistor 26b. A current flows through the light-emitting element 24 a of 24 and a series-connected circuit of the Zener diode 26 c and the DC power supply 21 for control of the indoor unit 2. In this case, since both terminals of the commercial AC power supply 10 are switched and connected to the control DC power supply 21 of the indoor unit 2, the control DC power supply 21 operates normally and the indoor The microcomputer 22 also operates normally. As a result, when the light-emitting element 24a of the indoor receiving photopower bracket 24 is energized, a commercial power supply frequency interrupt is generated for the indoor microcomputer 22. Therefore, it can be detected that the by treatment ¹ Furochiya Ichito processing and the third view of the flow chart of FIG. 2, faulty wiring occurs. That is, by determining whether the input and output match or not, it is possible to determine the presence or absence of incorrect wiring as a result. In this case, the fifth resistor 26 b is connected in series with the light-emitting diode 24 a of the indoor reception photocoupler 24, and the power is supplied through the termination resistor 17 and the series connection circuit. Therefore, there is no inconvenience that the light emitting element 24a of the indoor reception photocoupler 24 is destroyed. Fig. 13 shows a state in which the commercial power line 3a is incorrectly wired as the signal line 3c, the signal line 3c is commercial power line 3b, and the commercial power line 3b is commercial wire 3a. FIG.

In Fig. 13, in the half cycle of the commercial AC power supply 10, the light emitting element of the third diode 26a, the fifth resistor 26b, and the indoor receiving photo power plug 24, as indicated by the arrow A1, 24a and the Zener diode 26c connected in series, the second diode 18c, the fourth resistor 18d, and the outdoor reception A current flows through a series connection circuit of the light emitting element 16a and the Zener diode 18e of the photocoupler 16 and a termination resistor 17 connected in parallel with the series connection circuit. In this case, since the control DC power supply 21 of the indoor unit 2 does not start up, the indoor microcomputer 22 does not start up and no commercial power supply frequency interrupt occurs. However, a reception data interrupt occurs for the outdoor microcomputer 14. Therefore, it is possible to detect the occurrence of erroneous wiring by the processing of the flowchart in FIG. In this case, the fifth resistor 26 b and the termination resistor 17 are connected in series with the light emitting element 24 a of the indoor reception photocoupler 24, and the indoor reception photocoupler 2 is connected. Since the fifth resistor 26 b, the fourth resistor 18 d, and the light receiving element 16 a of the outdoor reception 16 are connected in series with the light emitting element 24 a of 4, the light receiving element 16 a of the outdoor reception 16 is connected. There is no inconvenience that the light emitting element 24 a of 4 is destroyed, and that the light emitting element 16 a of the outdoor reception photocabler 16 is destroyed.

Further, in this case, since the signal from the indoor unit 2 is not supplied to the outdoor unit 1, in the outdoor unit 1, miswiring is performed based on the time-out after the signal is transmitted. Can also be detected.

Fig. 14 shows a state where the commercial power line 3a is miswired with the commercial power line 3b, the signal line 3c with the commercial power line 3a, and the commercial power line 3b with the signal line 3c. FIG.

In FIG. 14, in the half cycle of the commercial AC power supply 10, as indicated by an arrow A1, the DC power supply 21 for control of the indoor unit 2 passes through the second diode 18c, the fourth resistor 18d, A current flows through the series connection circuit of the light-emitting element 16a and the zener diode 18e of the outdoor reception photocoupler 16 and the termination resistor 17 connected in parallel with the series connection circuit. A receive data interrupt occurs for icon 14. Also, commercial AC power supply In the other half cycle of 10, as indicated by arrow A 2, a current flows through the termination resistance 17, the DC power supply 21 for controlling the indoor unit 2, and the third diode 26 a, A current flows through the series connection circuit of the fifth resistor 26 b, the light-emitting element 24 a of the indoor reception photocoupler 24 and the zener diode 26 c, and the control DC power supply 21 of the indoor unit 2 is turned on. above the moon have Runode, _c thus utility frequency interruption is generated for the indoor microcomputer 2 2, by treatment Furochiya over preparative process Contact Yopi third view of Furochiya Ichito of FIG. 2, miswiring Can be detected. In this case, the commercial AC power is directly applied to the series connection circuit of the light emitting element 24a and the fifth resistor 26b of the indoor reception photocoupler 24. Since the fifth resistor 26 b is connected in series with the light emitting element 24 a of the tokabura 24, the inconvenience that the light emitting element 24 a of the indoor receiving photocoupler 24 is destroyed does not occur. Furthermore, a fourth resistor 1 Sd is connected in series with the light emitting element 16 a of the outdoor receiving photocoupler 16, and a termination resistor 1 is connected in parallel with the light emitting element 16 a of the outdoor receiving photocoupler 16. Since 7 is connected, the disadvantage that the light emitting element 16a is destroyed does not occur.

Of course, in any of FIGS. 10 to 14, the positive temperature characteristic thermistor 25 for overcurrent protection is connected in series with the light receiving element 23 b of the indoor transmission photocoupler 23. Therefore, even when the commercial AC power supply voltage is directly applied to this series connection circuit and the light receiving element 23 b of the indoor transmission photocoupler 23 is turned on, the indoor transmission photocoupler 23 The destruction of the light receiving element 23 b can be prevented beforehand.

As is evident from the above, it is necessary to determine whether there is a commercial power frequency interrupt and whether there is a receive data interrupt, and turn on the transmission port of the outdoor microcomputer 14 to determine whether the transmission output matches the reception input or not. By. It can be determined whether or not the wiring is incorrect.

In addition, a low-cost and space-saving communication control circuit can be provided because it is necessary only when wiring is incorrect and does not require a special wiring protection circuit that is not related to operation during normal operation. In addition, even in the case of erroneous wiring, it operates safely without damaging the transmission / reception circuit components, so that it is possible to provide a system with excellent maintainability that does not require replacement of a board or the like.

Also, since the transmitted and received data patterns appear as they are on the reception port as they are, the communication processing program between the outdoor unit and the indoor unit can be shared, and the initial communication state can be transmitted and received from both the outdoor unit and the indoor unit. are possible, furthermore, since the data of one device has transmitted wears the receiving at each device at the same time, communication efficiency, _c it is possible to provide a developing efficient system in the above embodiments, a positive A positive temperature characteristic thermistor for overcurrent protection is used as the second resistance means having a temperature coefficient.However, instead of a positive temperature characteristic thermistor for overcurrent protection, conductive force, polyolefin, and fluorine resin are used. It is possible to adopt a resistance element that is blended with a polymer such as

This air conditioner is different from the air conditioner shown in Fig. 1 in that a positive temperature characteristic thermistor 25 is replaced with a damping resistor 25 ', and the power supply 21 has a primary winding with a commercial AC power supply. The rectified output from the transformer 21 1a connected between the output terminals of 1 and the rectifier circuit 21b and the rectifier circuit 21b connected between the terminals of the secondary winding of the transformer 21a. An input that includes a DC power supply circuit for indoor control 21 c that performs smoothing processing, voltage stabilization processing, etc. as inputs, and abnormalities from the different voltage detection circuit as the different voltage detection circuit and indoor microcomputer 22 The only difference is that the system accepts input for detection. You.

This will be described in more detail.

Connect a resistor 21 d between the output terminal of the indoor control DC power supply circuit 21 c and the abnormality detection input of the indoor microcomputer 22, and connect the abnormality detection input of the indoor microcomputer 22 to a transistor 21 e. Grounded via the collector-emitter terminal of Then, a resistor 21 f is connected between the base terminal of the transistor 21 e and the emitter terminal, and a Zener diode is connected between the input terminal of the indoor control DC power supply circuit 21 c and the base terminal of the transistor 21 e. A diode (different voltage detecting means) 21 _g and a resistor 21 h are connected in series in this order. Therefore, the transistor 21e, the resistors 21d, 21f, 21h and the Zener diode 21g constitute a different voltage detecting means (circuit). In addition, it is possible to use digital transistors instead of the electric circuit composed of the transistor 21 e and the resistors 21 f and 21 h, and to set the polarity according to the signal to be output. It is. '

Fig. 16 is a flowchart explaining the miswiring determination process of the indoor unit. In step _c1 , the transmission port of the indoor microcomputer 22 is turned on (the light receiving element 23 of the indoor transmission photocoupler 23). To OFF), and in step SP2, determine the commercial power frequency interrupt. If it is determined that there is a commercial power frequency interrupt, the connection of the indoor / outdoor connection line 3 is recognized to be abnormal in step SP3, and an abnormal voltage is detected in step SP4. Is determined. If an abnormal voltage is detected, in step SP5, it is recognized that incorrect wiring other than polarity reversal (wrong wiring in FIG. 11 or FIG. 14) is detected. In step 6, the transmission port of the indoor microcomputer 22 is turned on (the light receiving element 23b of the indoor transmission photocoupler 23 is turned off), and the series of processing is terminated. If it is determined in step SP4 that no abnormal voltage has been detected, in step SP7, it is recognized that incorrect polarity inversion wiring (wrong wiring in Fig. 12) has been detected. In, the transmission port of the indoor microcomputer 22 is turned off (the light receiving element 23 b of the indoor transmission photocoupler 23 is turned on), and the series of processing is terminated as it is.

If it is determined in step SP2 that there is no commercial power frequency interrupt, in step SP9 it is recognized that the connection of the indoor / outdoor connection line 3 is normal, and in step SP10, the normal sequence is performed. Perform the base action.

This will be described in more detail.

In the case of incorrect wiring, a force rent loop that always passes through the termination resistor 17 is configured. Therefore, if the resistance value of the termination resistor 17 is set to be larger than the impedance of the transformer 21a, a normal voltage will not be generated on the secondary side of the transformer 21a. Even when the wiring is incorrect, if the power supply of the indoor microcomputer 22 (the indoor control DC power supply circuit 21c) is turned on, it is possible to monitor the voltage on the secondary side of the transformer 21a. In addition, when the wiring is incorrect, a pulse of the commercial power supply frequency is input to the reception port of the indoor microcomputer 22.Therefore, the presence of the pulse on the secondary side of the transformer 21a and the commercial power supply frequency The type of the incorrect wiring can be detected on the basis of this, and the protection of the communication circuit element can be achieved by performing the optimum protection processing according to the type of the incorrect wiring. In addition, by transmitting information indicating the type of incorrect wiring to the installer via a display device, etc., it is possible to improve workability for eliminating incorrect wiring and to promote safe connection. it can. In the case of miswiring other than the miswiring that can be detected by the processing of the flowchart in FIG. 16 (miswiring in FIGS. 10 and 13), the DC power supply circuit for indoor control of the indoor unit 2 is used. Since 2 1 c does not rise, There is no risk of the communication circuit element being destroyed.

Further, by performing the power feeding for communications by the DC power supply, conventional _cis; Temu communication speed as compared to the (system including a communication circuitry only that could not be synchronized to the transmission up to twice the Poreto the utility frequency) This makes it possible to construct a system that operates with almost no delay with respect to input from a remote controller (not shown) and that does not cause any uncomfortable feeling. This operation can be achieved in all other embodiments.

In each of the above embodiments, when adopting a configuration in which one indoor unit 2 is provided for one outdoor unit 1, the circuit configuration of the indoor unit 1 and the circuit configuration of the indoor unit 2 are switched. It is possible. INDUSTRIAL APPLICABILITY The indoor / outdoor communication device in the air conditioner of the present invention is an air conditioner in which an indoor unit is connected to an outdoor unit via three connection lines including a commercial power supply line. This eliminates the need for extraneous circuit configurations during normal indoor / outdoor communication operations, such as power supply switching means and different voltage detection protection sections, and allows the transmission and reception circuit components to be used even if incorrect wiring occurs. Problems such as destruction and disconnection can be prevented before they occur.

Claims

The scope of the claims

1. An air conditioner that connects an indoor unit (2) to an outdoor unit (1) via three connection lines (3) including a commercial power line (3a) (3b)

One of the outdoor unit (1) and the indoor unit (2)

A signal is exchanged between the first control means (14), the first power supply means (11) for supplying power to the first control means (14), and the first control means (14). The first transmitting photobra (15) and the first receiving photobra (16) connected in series between the terminals of the commercial AC power supply (10) via DC power supply means (12). ) And first resistance means (17) connected in parallel with the first receiving photocoupler (16).

The other of the outdoor unit (1) and the indoor unit (2)

Signals are exchanged between the second control means (2 2) and the second control means (2 2), and the first receiving photo-sensor is connected via two of the three connection lines (3). The second receiving photobra (23), the second transmitting photobra (23) and the second transmitting photobra (23) are connected in series with the power bra (16). And second resistance means (25) for suppressing overcurrent at the time of incorrect wiring

An indoor / outdoor communication device in an air conditioner, characterized in that:

2. Multiple indoor units (2) are connected in parallel to one outdoor unit (1) via three connection lines (3) including commercial power lines (3a) and (3b). In the connected air conditioner,

The outdoor unit (1) exchanges signals between the outdoor control means (14), the outdoor control power supply means (11), and the outdoor control means (14), and uses the commercial AC power supply (1). 0) between the terminals via DC power supply means (1 2) An outdoor transmission photo coupler (15), an outdoor reception photo coupler (16) connected in series, and a first resistance means (17) connected in parallel with the outdoor reception photo coupler (16). Including

Each indoor unit (2) is connected to a terminal of a commercial AC power supply (10) via a commercial power supply line (3a) (3b), and a room / control power supply means (21). Signals are transmitted and received between the control means (22) and the indoor control means (22), and the outdoor reception photopower (1) is transmitted via two of the three connection lines (3). Incorrect wiring that is connected in series with the indoor receiving photo power bra (24), the indoor transmitting photo power bra (23), and the indoor transmitting photo power bra (23) connected in parallel with 6). And second resistance means (25) for suppressing overcurrent at the time.

3. The indoor / outdoor communication device for an air conditioner according to claim 1, wherein the second resistance means (25) is a positive temperature characteristic thermistor (25).

4. Air conditioning by connecting the indoor unit (2) in parallel with the outdoor unit (1) via three connection lines (3) including commercial power lines (3a) and (3b) In the device,

One of the outdoor unit (1) and the indoor unit (2)

A signal is exchanged between the first control means (14), the first power supply means (11) for supplying power to the first control means (14), and the first control means (14). And a first transmitting photocoupler (15) and a first receiving photobra (16) connected in series between the terminals of a commercial AC power supply (10) via DC power supply means (12). And a first receiving means (17) connected in parallel with the first receiving photocoupler (16),

The other of the indoor unit (2) and the indoor unit (2) The transformer (21a) connected to the terminal of the commercial AC power supply (10) via the commercial power supply line (3a) (3b) and the output voltage from the transformer (21a) are converted to DC voltage. Rectifier means (2 1 b) for converting the voltage into a different voltage, different voltage detecting means (21 g) which operates based on the converted DC voltage, and a second terminal connected between the output terminals of the rectifier means (2 1 b). A signal is exchanged between the power supply means (2 1 c), the second control means (22) to which the converted DC voltage is applied, and the second control means (22), and three connection lines are provided. The second receiving photobra (24) and the second transmitting photobra (2) connected in parallel with the first receiving photobra (16) via two of the (3) 3) and a second resistance means (25 ') connected in series with the second transmitting photo-bra (23).

5. Multiple indoor units (2) 'are connected in parallel to one outdoor unit (1) via three connection lines (3) including commercial power lines (3a) and (3b). In an air conditioner connected to

The outdoor unit (1) includes an outdoor control means (14), an outdoor control power supply means (11) for supplying power to the outdoor control means (14), and an outdoor control means (14). Between the terminals of the commercial AC power supply (10) and the series connection between the terminals of the commercial AC power supply (10) via the DC power supply means (12); (16) and first resistance means (17) connected in parallel with the outdoor credit photobra (16),

Each indoor unit (2) has a transformer (21a) connected to a terminal of a commercial AC power supply (10) via a commercial power supply line (3a) (3b), and a transformer (21a). ) To convert the output voltage from the DC voltage into a DC voltage (2 lb), and a different voltage detecting means (2 1 g), power supply means for indoor control (21c) connected between the output terminals of the rectifier means (21b), and indoor control means (22) to which the converted DC voltage is applied. And the indoor control means (22) which transmits and receives signals and which is connected in parallel with the outdoor reception photocabler (16) via two of the three connection lines (3). Including a photobra for reception (24), a photobra for indoor transmission (23), and a second resistance means (25 ') connected in series with the photobra for indoor transmission (23)