JP2916656B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separate type air conditioner, and more particularly to an air conditioner having a serial signal transmission circuit for transmitting information between an indoor unit and an outdoor unit.

[0002]

2. Description of the Related Art An air conditioner of this type has conventionally used a digital serial transmission system for information transmission between an indoor unit and an outdoor unit.

In the past, wiring between an indoor unit and an outdoor unit was often performed by using two AC lines and two DC circuits for transmitting serial signals, but recently, two wires have been used to reduce the number of wirings. Of these AC lines, one side line is commonly used as a DC power supply line, and furthermore, a single serial signal line is often configured with a total of three wirings.

According to the present invention, an air conditioner in which wiring between an indoor unit and an outdoor unit is provided with three serial signal transmission circuits, or a serial signal transmission circuit in which four wirings are conventionally provided. Related to air conditioners.

In such a conventional air conditioner, when wiring is performed between an indoor unit and an outdoor unit during installation work, an AC signal is applied to the outdoor unit by performing an operation regardless of whether there is a wiring error. The wiring was checked for the first time by operating the outdoor unit control circuit and checking whether the serial signal transmission circuit operated normally.

[0006]

As described above, in the conventional air conditioner, the wiring is checked only after the AC power is applied to the outdoor unit and the outdoor unit control circuit is operated. At the time when the power plug was turned on and AC power was applied to the indoor unit, no wiring error could be detected. Therefore, it is necessary to provide a protection circuit so as not to damage circuit components even if there is a wiring error, or to use components having high withstand voltage specifications.

An object of the present invention is to solve the above problems,
An object of the present invention is to provide an air conditioner capable of reliably performing a wiring inspection at the time when AC power is applied to an indoor unit before applying AC power to an outdoor unit .

[0008]

An air conditioner according to a first aspect of the present invention includes an indoor unit and an outdoor unit that share an AC power supply line, and a DC power supply line is provided between the indoor unit and the outdoor unit and on one side. Are connected by two AC power supply lines shared with the AC power supply line and one serial signal line separately provided, and extend over the indoor unit and the outdoor unit by the DC power supply line and the serial signal line shared with the AC power supply line. An air conditioner in which a serial signal transmission circuit including a DC loop circuit is formed and configured to transmit a serial signal in both directions from the indoor unit to the outdoor unit and from the outdoor unit to the indoor unit. DC loop testing mode, the serial signal transmission circuit after a predetermined time from the application of DC power to the DC power supply line which is shared with the AC power line before the application of AC power to By checking whether or not a path is formed, the presence of incorrect wiring between the indoor unit and the outdoor unit is inspected.If there is an incorrect wiring, the incorrect wiring is displayed and the AC power to the outdoor unit is displayed. The invention is characterized in that application of power is prohibited.

For example, the indoor unit is provided with a main relay contact for controlling the application of AC power to the outdoor unit, a DC power supply circuit, an operation circuit, a display circuit, a serial signal transmission / reception circuit, and an indoor unit control circuit. The unit is provided with a power supply circuit, a serial signal transmission / reception circuit and an outdoor unit control circuit, and the serial signal transmission / reception circuit of the indoor unit and the outdoor unit is provided with:
There are provided a transmission element comprising a transmission input element and a transmission switch element, and a reception element comprising a reception input element and a reception switch element, respectively. The DC loop circuit of the serial signal transmission circuit is formed by the switch element, the transmission switch element and the reception input element of the outdoor unit, the DC power line shared with the AC power line, and the serial signal line, and the serial signal transmission and reception of the outdoor unit The inspection switch element is connected in parallel to the transmission switch element of the circuit, and in the inspection mode before applying the AC power to the outdoor unit, the indoor unit control circuit operates the indoor unit with the inspection switch element closed. DC loop of the serial signal transmission circuit after a predetermined time to close the transmission switch element of the serial signal transmission and reception circuit Check whether a path is formed.If a DC loop circuit is formed, determine that there is no incorrect wiring.If a DC loop circuit is not formed, determine that there is incorrect wiring. In addition to displaying the incorrect wiring, the main relay contact is kept open even if the operation is performed, and the application of AC power to the outdoor unit is prohibited. When performed, the AC power is applied to the outdoor unit, and while the AC is applied to the outdoor unit and the outdoor unit control circuit is energized,
The inspection switch element is opened.

For example, the inspection switch element is a break contact of a relay connected to the outdoor unit control circuit. This relay is turned off while the outdoor unit control circuit is not energized, and is turned on when the outdoor unit control circuit is energized. It is made to turn on while you are.

For example, the inspection switch element is a positive characteristic semiconductor element attached to a heat sink of a power supply circuit of an outdoor unit.

For example, the inspection switch element is a Zener diode, and the indoor unit control circuit switches the output of the DC power supply circuit to a voltage higher than the breakdown voltage of the Zener diode in the inspection mode. Is switched to a voltage lower than the breakdown voltage of the Zener diode.

An air conditioner according to a second aspect of the present invention includes an indoor unit and an outdoor unit that share an AC power supply line, and a space between the indoor unit and the outdoor unit is provided separately from two AC power supply lines. Connected by two serial signal lines
A serial signal transmission circuit including a DC loop circuit extending between the indoor unit and the outdoor unit is formed by the serial signal line, and serial signals are bidirectionally transmitted from the indoor unit to the outdoor unit and from the outdoor unit to the indoor unit. In the air conditioner configured to transmit, in the inspection mode before applying AC power to the outdoor unit, a predetermined time after applying DC power to the DC power line connected to the serial signal line,
By checking whether a DC loop circuit of the serial signal transmission circuit is formed in the indoor unit, it is checked whether there is incorrect wiring between the indoor unit and the outdoor unit, and if there is an incorrect wiring, the indication of the incorrect wiring is displayed. In addition, the invention is characterized in that application of AC power to the outdoor unit is prohibited.

For example, the indoor unit is provided with a main relay contact for controlling the application of AC power to the outdoor unit, a DC power supply circuit, an operation circuit, a display circuit, a serial signal transmission / reception circuit, and an indoor unit control circuit. The unit is provided with a power supply circuit, a serial signal transmission / reception circuit and an outdoor unit control circuit, and the serial signal transmission / reception circuit of the indoor unit and the outdoor unit is provided with:
There are provided a transmission element comprising a transmission input element and a transmission switch element, and a reception element comprising a reception input element and a reception switch element, respectively. A DC loop circuit of a serial signal transmission circuit is formed by the switch element, the transmission switch element and the reception input element of the outdoor unit, and the two serial signal lines, and is used as a transmission switch element of the serial signal transmission and reception circuit of the outdoor unit. Inspection switch elements are connected in parallel, and in the inspection mode, the indoor unit control circuit closes the transmission switch element of the serial signal transmission / reception circuit of the indoor unit in a state where the inspection switch element is closed, and the indoor unit control circuit performs serial communication after a predetermined time. Check whether the DC loop circuit of the signal transmission circuit is formed. When there is no incorrect wiring, and when the DC loop circuit is not formed, it is determined that there is incorrect wiring.If there is incorrect wiring, the incorrect wiring is displayed by the display circuit and the main operation is performed even if the driving operation is performed. Holding the relay contact in the open state, prohibiting the application of AC power to the outdoor unit, and if there is no incorrect wiring, when the operation is performed,
An AC power supply is applied to the outdoor unit, and while the AC power supply is applied to the outdoor unit and a current is supplied to the outdoor unit control circuit, the inspection switch element is opened.

For example, the inspection switch element is a break contact of a relay connected to the outdoor unit control circuit. This relay is turned off while the outdoor unit control circuit is not energized, and is turned on when the outdoor unit control circuit is energized. It is made to turn on while you are.

For example, the inspection switch element is a positive characteristic semiconductor element attached to a heat sink of a power supply circuit of an outdoor unit.

For example, the inspection switch element is a Zener diode, and the indoor unit control circuit switches the output of the DC power supply circuit to a voltage higher than the breakdown voltage of the Zener diode in the inspection mode. Is switched to a voltage lower than the breakdown voltage of the Zener diode.

[0018]

[Function] Like most air conditioners these days,
In the air conditioner according to the present invention, when the power plug is turned on and no operation is performed, the indoor unit control circuit is energized, but the AC power of the outdoor unit is not energized.

At this time, the inspection mode is set,
Inspection of wiring between the indoor unit and the outdoor unit is performed.

In the air conditioner according to the first invention,
A predetermined time after DC power is applied to the DC power line shared with the AC power line, it is checked whether or not a DC loop circuit of the serial signal transmission circuit is formed. The presence or absence of incorrect wiring is inspected. When the DC loop circuit is formed, it is determined that there is no incorrect wiring, and when the DC loop circuit is not formed, it is determined that there is incorrect wiring. In particular, AC power line
DC power is applied to the DC power line shared with
After a predetermined time from, the DC loop of the serial signal transmission circuit
Checks whether a circuit is formed.
Regardless of the wire mode, the presence or absence of incorrect wiring is reliably determined.
It is.

When there is an error in wiring connection, for example, by keeping the main relay contact in an open state, no AC power is supplied to the outdoor unit, and an incorrect wiring display is performed by the indoor unit control circuit. Control.

However, in the above description, energization of the AC power supply to the outdoor unit means that, of the wiring between the indoor unit and the outdoor unit, the AC power supply line not sharing the wiring with the DC power supply line is connected to, for example, an indoor unit control circuit. Means that it is turned on and off by the contact of a main relay. Therefore, even when the AC power supply to the outdoor unit is in a non-energized state, the remaining 2
A DC circuit is constituted by these lines.

When the wiring is normal, when the operation of the air conditioner is performed, for example, the indoor unit control circuit turns on the contact of the main relay to supply AC power to the outdoor unit.

When the AC power is supplied to the outdoor unit, for example, the outdoor unit control circuit is also energized, and the inspection switch element connected in parallel to the transmission switch element of the serial signal transmission / reception circuit of the outdoor unit opens. As a result, a DC loop circuit of a conventional serial signal transmission circuit can be configured.

The inspection switch element is a break contact of a relay connected to the outdoor unit control circuit.
If the outdoor unit control circuit is turned off while not energized and the outdoor unit control circuit is turned on while energized, the outdoor unit is in the inspection mode before AC power is applied to the outdoor unit. Because the machine control circuit is not energized,
The relay is off and the break contact is closed. Then, when the outdoor unit control circuit is energized, the relay is turned on and the break contact is opened.

When the inspection switch element is a positive characteristic semiconductor element attached to the heat sink of the power supply circuit of the outdoor unit, the heat sink is in a cold state in the inspection mode before AC power is applied to the outdoor unit. The positive characteristic semiconductor element has a low resistance and is in a closed state. When AC power is applied to the outdoor unit, the temperature of the heat sink rises, the positive characteristic semiconductor element has a high resistance value, and is in an open state.

The inspection switch element is a Zener diode, and the indoor unit control circuit switches the output of the DC power supply circuit to a voltage higher than the breakdown voltage of the Zener diode in the inspection mode, and outputs the output of the DC power supply circuit in other than the inspection mode. Is switched to a voltage lower than the breakdown voltage of the Zener diode, the voltage of the DC power supply circuit is switched to a voltage higher than the breakdown voltage of the Zener diode in the test mode, so that the Zener diode is closed. is there. In a mode other than the inspection mode, the voltage of the DC power supply circuit is switched to a voltage lower than the breakdown voltage of the Zener diode, so that the Zener diode is in an open state.

The same applies to the air conditioner according to the second invention.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the drawings. In all the embodiments, common parts are denoted by the same reference numerals.

FIGS. 1 and 2 show a first embodiment. FIG. 1 is an electric block diagram of a main part of an air conditioner.
FIG. 2 is an electric circuit diagram of a main part of FIG. 1.

In FIG. 1, the air conditioner is of a separate type comprising an indoor unit (1) and an outdoor unit (2) which share an AC power supply line. The indoor unit (1) includes a DC power supply circuit (first DC power supply circuit) (3), a DC power supply circuit for serial signal transmission (second DC power supply circuit) (4), and a relay drive circuit.
(5), main relay contact (6), operation circuit (7), display circuit
(8) A serial signal transmitting / receiving circuit (9), other indoor unit input / output circuits (10), an indoor unit control circuit (11), and a terminal board (12) are provided. The outdoor unit (2) includes a power supply circuit for the outdoor unit inverter (13), a serial signal transmission / reception circuit (14), a relay for inspection (15), other outdoor unit input / output circuits (16), and an outdoor unit control circuit (17). ) And a terminal plate (18) are provided.

Terminal board (12) for indoor unit (1) and outdoor unit (2)
(18) has three terminals (12a) (12b) (12c) (18a)
(18b) and (18c) are provided. Indoor unit (1) and outdoor unit (2)
The first terminals (12a) and (18a) are connected by an electric wire (19a) constituting an independent first AC power supply line (19). The second terminals (12b) and (18b) of the indoor unit (1) and the outdoor unit (2) are connected to each other to form a second AC power supply line (common line) (20) shared with a DC power supply line (20). Connected by Third terminal (12c) of indoor unit (1) and outdoor unit (2)
(18c) Wires composing serial signal line (21)
(21a).

The first DC power supply circuit (3) is connected to the indoor unit control circuit (1).
This is for supplying DC power to 1), and is connected to an AC power supply (22) by inserting a power plug (not shown).

The second DC power supply circuit (4) has a second AC power supply line on one side for wiring between the indoor unit (1) and the outdoor unit (2).
Since (20) and the DC power supply line are shared, it cannot be insulated from the AC power supply circuit, and therefore is provided separately from the first DC power supply circuit (3).

The main relay contact (6) is for controlling the application of AC power to the outdoor unit (2), and is provided on the first AC power line (19). Relay drive circuit (5)
Is for controlling a main relay (not shown) for controlling on / off of the main relay contact (6).

The operation circuit (7) is for performing various operations of the air conditioner such as turning on / off the operation using a wireless remote controller or manually.

The display circuit (8) is a circuit for displaying various operating states of the air conditioner using LEDs (light emitting diodes) or the like. The incorrect wiring indication related to the present invention also
It is included in this display circuit (8).

The indoor unit control circuit (11) is for controlling the entire indoor unit (1) and includes a microcomputer.

The indoor unit input / output circuit (10) is for connecting another input / output device (not shown) to the indoor unit control circuit (11).

A fuse (FU1) is provided in a first AC power supply line (19) between the first terminal (18a) of the outdoor unit (2) and the inverter power supply circuit (13). The DC power supply for the outdoor unit control circuit (17) is changed from the AC power supply (22) to the inverter power supply circuit (13).
Power supply circuit for the inverter when the main relay contact (6) is closed.
AC power is applied to (13), and the outdoor unit control circuit (17) is energized.

The serial signal transmission / reception circuits (9) and (14) of the indoor unit (1) and the outdoor unit (2) transmit operation mode and operation level instruction information from the indoor unit (1) to the outdoor unit (2). ,Outdoor unit
From (2) to the indoor unit (1), a defrost request, inverter operation level information, error information when a failure occurs, and the like are sent.

FIG. 2 shows a second DC power supply circuit of the indoor unit (1).
(4) and details of a serial signal transmission / reception circuit (9), and details of an inverter power supply circuit (13) and a serial signal transmission / reception circuit (14) of the outdoor unit (2).

The second DC power supply circuit (4) includes a fuse (FU2)
, A diode (D1), resistors (R1) and (R2), a Zener diode (ZD1), an electrolytic capacitor (C1), and the like.

The inverter power supply circuit (13) includes a noise filter (23), a reactor (24), a bridge full-wave rectifier circuit (25), and electrolytic capacitors (C2) (C3) (C4).

Transmission / reception circuit of indoor unit (1) and outdoor unit (2)
(9) and (14) are transmitting PCs (photocouplers) (26) and (27) as transmitting elements and receiving PCs (28) as receiving elements, respectively.
(29). Each of the transmission PCs (26) and (27) includes a transmission LED (26a) (27a) as a transmission input element and a transmission PT (phototransistor) (26b) as a transmission switch element.
(27b). Each receiving PC (28) (29)
Is composed of receiving LEDs (28a) (29a) as receiving input elements and receiving PTs (28b) (29b) as receiving switch elements. LED (26a) of each PC (26) (27) (28) (29)
The resistor (R3) is connected in parallel to (27a), (28a) and (29a). On the indoor unit (1) side, the receiving PC of the receiving PC (28)
T (28b) is connected to the input terminal (IN) of the indoor unit control circuit (11), and the transmission LED (26a) of the transmission PC (26) is connected to the output terminal (OUT2) of the indoor unit control circuit (11). It is connected. Outdoor unit
(2) On the side, the transmission LED (27a) of the transmission PC (27)
Is connected to the output terminal (OUT) of the outdoor unit control circuit (17), and the reception PT (29b) of the reception PC (29) is connected to the outdoor unit control circuit (17).
Is connected to the input terminal (IN). Then, the common line (20) on the positive side of the second DC power supply circuit (4) and the second common line of the indoor unit (1)
Terminal (12b), electric wire (20a), second terminal (18b) of outdoor unit (2)
, Outdoor unit (2) PT (27b) for transmission and LED for reception
(29a), diode (D2), resistance (R4), third unit of outdoor unit (2)
Terminal (18c), electric wire (21a) of signal line (21), indoor unit (1)
3rd terminal (12c), resistance (R5), diode (D3), indoor unit
A DC loop circuit is constituted by the receiving LED (28a) and the transmitting PT (26b) of (1), and the negative side of the second DC power supply circuit (4). The reason for using the PCs (26) to (29) as the transmitting element and the receiving element is that the commercial AC power supply (22)
This is for electrically insulating the AC circuit from the indoor unit control circuit (11) or the outdoor unit control circuit (17).

An inspection relay (15) is connected to the outdoor unit control circuit (17), and its break contact (15b) is connected in parallel to the transmission PT (27b) of the outdoor unit (2). This relay (15)
Is off while the outdoor unit control circuit (17) is not energized, and is on while the outdoor unit control circuit (17) is energized.

In the above air conditioner, when the power plug is turned on, AC power is applied to the first DC power circuit (3) and the second DC power circuit (4), and the first DC power circuit is turned on.
From (3), DC power is applied to the indoor unit control circuit (11), and a DC loop circuit is formed by the shared line (20) and the signal line (21). However, even if the power plug is turned on, the main relay contact (6) is off until the operation is performed from the operation circuit (7), and the inverter power supply circuit (13) of the outdoor unit (2) is turned off. And no DC power is applied to the outdoor unit control circuit (17). Therefore, the inspection relay (15) is turned off, the break contact (15b) is turned on, and both ends of the transmission PT (27b) of the outdoor unit (2) are short-circuited. Then, in such a state from when the power plug is turned on to when the driving operation is performed, the indoor unit control circuit (11) enters the inspection mode, and the wiring inspection described later is performed. As a result of this inspection, if there is an error with incorrect wiring, the display circuit (8) indicates that there is incorrect wiring, and the main relay contact (6) remains off even if operation is performed. Yes, AC power is not applied to the outdoor unit (2). If there is no miswiring and the operation is performed, the main relay contact (6) will turn on and
AC power is applied to the outdoor unit (2). As a result, DC power is applied to the outdoor unit control circuit (17), and the inspection relay (1) is applied.
5) is turned on, the break contact (15b) is turned off, and the normal operation of the air conditioner is executed.

FIG. 3 is a flowchart showing an example of the wiring inspection process of the indoor unit control circuit (11). Next, the operation of the indoor unit control circuit (11) in the inspection mode and the states of the circuits of the indoor unit (1) and the outdoor unit (2) in the inspection mode will be described with reference to FIGS.

When the power plug is turned on, power is supplied to the indoor unit control circuit (11) and the serial signal transmission / reception circuit (9), so that the ON signal is output from the output terminal (OUT2) of the indoor unit control circuit (11). To turn on the transmission PC (26). That is, the transmission LED (26a) is turned on, and the transmission PC (26) is turned on (step 1). Then, it waits for 3 seconds in that state (step 2). Here, the reason for waiting for 3 seconds is that the transmission PC (2
This is because the wiring cannot be checked for 3 seconds after turning on 6), which will be described in detail later. After 3 seconds have elapsed, the input terminal (I
Checking the voltage level of N)
It is checked whether (28) is on (step 3). And if the receiving PC (28) is on,
It is determined that there is no incorrect wiring in the normal state, and the process proceeds to the normal processing program to perform a normal operation. In step 3, if the receiving PC (28) is turned off, it is determined that there is an abnormal state with incorrect wiring, the process proceeds to step 4, and the display of the incorrect wiring is repeated, and the normal operation is not performed. .

When the wiring between the indoor unit (1) and the outdoor unit (2) is normal, a DC loop circuit is formed by the common line (20) and the signal line (21). As described above, the break contact (15b) of the inspection relay (15) is closed, and both ends of the transmission PT (27b) of the outdoor unit (2) are short-circuited. PC
When (26) is turned on, a DC current flows through this DC loop circuit, the receiving LED (28a) of the indoor unit (1) is turned on, and the receiving PT (28b) is turned on. That is, the receiving PC (28) is turned on. This allows the indoor unit control circuit (1
The voltage level of the input terminal (IN) of 1) becomes H level, this is detected by the indoor unit control circuit (11), and it is determined that it is in a normal state.

In the normal state with no incorrect wiring, when the operation of the air conditioner is performed after the inspection, the indoor unit control circuit (1)
1) is the main relay contact (6) via the relay drive circuit (5)
Is turned on, whereby AC power is applied to the outdoor unit (2), and the outdoor unit control circuit (17) is energized. Outdoor unit control circuit
The inspection relay (15) turns on in synchronization with the energization of (17),
The break contact (15b) is turned off. As a result, it becomes the same as when there is no break contact (15b), and signals can be transmitted and received as in the conventional case.

When the operation of stopping the operation of the air conditioner is performed, the indoor unit control circuit (11) turns off the main relay contact (6) via the relay drive circuit (5), and the outdoor unit (2) The application of AC power to the outdoor unit is stopped, and the power to the outdoor unit control circuit (17) is also cut off. As a result, the inspection relay (15) is turned off again, and its break contact (15b) is turned on. In this embodiment, the wiring inspection is performed only when the power plug is turned on. However, the wiring inspection may be performed while the operation of the air conditioner is stopped.

Next, a description will be given of what phenomenon occurs when there is a miswiring between the indoor unit (1) and the outdoor unit (2).

First, in the above embodiment, there are five modes shown in FIG. 4 in the miswiring mode between the indoor unit (1) and the outdoor unit (2).

In the case of the miswiring mode 1 shown in FIG. 4A, even if the transmission PC (26) of the indoor unit (1) is turned on during the wiring inspection, the DC loop circuit is opened by the diode (D2). Therefore, no current flows through the receiving LED (28a) of the indoor unit (1), and the receiving PC (28) remains off. Therefore, the voltage level of the input terminal (IN) of the indoor unit control circuit (11) remains at the L level, and it is determined in step 3 of FIG. 3 that there is an erroneous wiring.

In the case of the incorrect wiring mode 2 shown in FIG. 4 (b), when the transmission PC (26) of the indoor unit (1) is turned on during the wiring inspection, the positive side of the second DC power supply circuit (4) and the indoor Second terminal (12b) of unit (1), second terminal (18b) of outdoor unit (2), power supply circuit for inverter (13), fuse (FU1), first terminal of outdoor unit (2)
(18a), the third terminal (12c) of the indoor unit (1), the resistor (R5), the diode (D3), the receiving LED (28a) and the transmitting PT (26).
b) A loop circuit is created, and a direct current flows through this loop circuit, so that the receiving LED (28a) is turned on,
The receiving PC (28) is turned on, but the receiving LED (28a) is turned on for about one second and then turned off. This is caused by the second DC power circuit (4) of the indoor unit (1).
It takes time to charge the electrolytic capacitors (C2) (C3) (C4) of the inverter power supply circuit (13) through (R5),
The voltage on the input side of the receiving PC (28) in (1) is the receiving LED (2
8a) has a forward voltage drop of about 1.2 V or less, and the resistance (R3)
Loop current flows only to the receiving PC (2
8) is turned off. Therefore, also in this case, the indoor unit control circuit (1) is turned on three seconds after the transmission PC (26) is turned on.
By checking the voltage level of the input terminal (IN) of 1), it is possible to check for incorrect wiring.

In the case of the incorrect wiring mode 3 shown in FIG. 4 (c), when the transmission PC (26) of the indoor unit (1) is turned on during the wiring inspection, the positive side of the second DC power supply circuit (4) and the indoor The second terminal (12b) of the unit (1), the first terminal (18a) of the outdoor unit (2), the fuse (FU
1), power supply circuit for inverter (13), break contact (15b) of relay (15), LED for reception (29a), diode (D2),
Resistance (R4), third terminal (18c) of outdoor unit (2), third terminal (12c) of indoor unit (1), resistance (R5), diode (D3), receiving L
A loop circuit is formed by the ED (28a) and the transmission PT (26b), and a direct current flows through this loop circuit, so that the reception LED (28a) is turned on and the reception PC (28) is turned on. The receiving LED (28a) is turned on for about 2 seconds and then turned off. This is achieved by the electrolytic capacitor (C2) of the outdoor unit inverter power supply circuit (13) through the resistance (R5), the resistance (R4), and the break contact (15b) by the second DC power supply circuit (4) of the indoor unit (1). It takes time to charge (C3) and (C4), and the voltage on the input side of the receiving PC (28) of the indoor unit (1) is less than the forward voltage drop of about 1.2V of the receiving LED (28a). Value, the loop current flows only through the resistor (R3),
This is because the receiving PC (28) is turned off. Therefore, also in this case, it is possible to check for erroneous wiring by checking the voltage level of the input terminal (IN) of the indoor unit control circuit (11) three seconds after turning on the transmission PC (26).

In the case of the miswiring mode 4 shown in FIG. 4D, the miswiring can be checked in substantially the same manner as in the mode 2 described above.

In the case of the miswiring mode 5 shown in FIG. 4 (e), the loop circuit is opened by the diode (D2) as in the case of the above-described mode 1, and the miswiring can be checked.

FIGS. 5 and 6 show a second embodiment. FIG. 5 is an electric block diagram of a main part of the air conditioner.
6 is an electric circuit diagram of a main part of FIG.

The outdoor unit (2) of the second embodiment is different from the outdoor unit (2) of the first embodiment in that the inspection relay (15) and its break contact (1) are provided.
5b) is removed, and a positive-characteristic semiconductor device (30) is added instead. As the positive characteristic semiconductor device (30),
For example, a PTC thermistor whose resistance value is increased about 10 times by a temperature rise of 20 to 30 ° C. is used. The positive characteristic semiconductor element (30) is attached to a heat sink (not shown) of the power supply circuit (13) of the outdoor unit (2), and the transmission PT of the outdoor unit (2) is mounted.
(27b). Others are the same as in the first embodiment.

In the above-described air conditioner, in the inspection mode before AC power is applied to the outdoor unit (2), since the heat sink is in a cold state, the positive characteristic semiconductor element (30) has a low resistance value. , And is in the same state that both ends of the transmission PT (27b) of the outdoor unit (2) are short-circuited. Accordingly, an inspection for an erroneous wiring can be performed as in the case of the first embodiment. In the case of a normal state with no incorrect wiring, the operation of the air conditioner is performed after the inspection, and the outdoor unit is operated.
When the AC power is applied to (2), the outdoor unit control circuit (17) is energized, and the heat sink becomes hot. As a result, the positive-characteristic semiconductor element (30) has a high resistance value and is in an open state. become able to.

FIG. 7 shows a third embodiment. FIG. 7 is an electric circuit diagram corresponding to FIG. 2 and FIG. The electric block diagram of the main part of the third embodiment is similar to that of FIG.
In this embodiment, the configurations of the second DC power supply circuit (4) and the serial signal transmission / reception circuit (9) of the indoor unit (1) and the serial signal transmission / reception circuit (14) of the outdoor unit (2) are the same as those of the second embodiment. A little different.

As shown in FIG. 7, the second DC power supply circuit (4)
PC for voltage switching (31), Zener diode (Z
D2) and a diode (D4) are added. The Zener diode (ZD2) is connected in series with the Zener diode (ZD1). The LED (31a) of the PC (31) is connected to the output terminal (OUT1) of the indoor unit control circuit (11), and the PT (31b) is connected in parallel to the Zener diode (ZD2). A resistor (R6) is connected in parallel to the LED (31a). The PC (31) is an output terminal (OUT1) of the indoor unit control circuit (11).
Is turned on / off by a signal from When the PC (31) is turned off and the PT (31b) is turned off, the Zener diode (ZD2) becomes effective, and the output of the DC power supply circuit (4) is switched to a high output voltage. When PC (31) turns on and PT (31b) turns on, a Zener diode (ZD
2) is short-circuited at both ends, and the output of the DC power supply circuit (4) is switched to a low output voltage. In the serial signal transmission / reception circuit (14) of the outdoor unit (2), a Zener diode (ZD3) is provided instead of the positive characteristic semiconductor element (30) of the second embodiment, and this is connected in parallel to the transmission PT (27b). Have been.
The high output voltage of the DC power supply circuit (4) is higher than the breakdown voltage of the Zener diode (ZD3), and the low output voltage of the DC power supply circuit (4) is lower than the breakdown voltage. Others are the same as the case of the second embodiment.

In the above air conditioner, in the inspection mode, an inspection mode signal (OFF signal) is output from the output terminal (OUT1) of the indoor unit control circuit (11), whereby the PC (3
1) is turned off, and the output of the DC power supply circuit (4) becomes a high output voltage higher than the breakdown voltage of the Zener diode (ZD3).
Then, in such a state, the wiring inspection is performed in the same manner as in the previous two embodiments.

When the wiring between the indoor unit (1) and the outdoor unit (2) is normal, a DC loop circuit is constituted by the common line (20) and the signal line (21). The output of the DC power circuit (4) is
Since the output voltage has been switched to a higher output voltage than the breakdown voltage of (ZD3), when the transmission PC (26) of the indoor unit (1) is turned on, DC current flows through this DC loop circuit, and the indoor unit (1 )
The receiving LED (28a) turns on and the receiving PC (28)
Turns on. As a result, the voltage level of the input terminal (IN) of the indoor unit control circuit (11) becomes H level, which is detected by the indoor unit control circuit (11), and is determined to be normal.

In a normal state without erroneous wiring, after the inspection,
The normal operation mode signal (ON signal) is output from the output terminal (OUT1) of the indoor unit control circuit (11), and the PC (31)
Is turned on, and the output of the DC power supply circuit (4) has a low output voltage lower than the breakdown voltage of the Zener diode (ZD3). Then, when the operation of the air conditioner is performed, the indoor unit control circuit (11) turns on the main relay contact (6) via the relay drive circuit (5), thereby connecting the outdoor unit (2) to the outdoor unit (2). An AC power supply is applied to energize the outdoor unit control circuit (17). At this time, the output of the DC power supply circuit (4) is a Zener diode (ZD
3) Since the output voltage is switched to a low output voltage lower than the breakdown voltage, the Zener diode (ZD3) will not be closed, and as a result, it will be the same as without the Zener diode (ZD3), and Signal transmission and reception.

In the above embodiment, the indoor unit (1) and the outdoor unit (2)
Are connected by a total of three lines of two AC power supply lines (19) and (20) and one serial signal line (21). The present invention relates to an indoor unit and an outdoor unit. Are similarly connected when two AC signal lines and two serial signal lines provided separately are connected by a total of four lines.

An example is shown in FIG. 8 as a fourth embodiment.

In the case of the fourth embodiment, four terminals (12a) (12) are connected to the terminal plates (12) and (18) of the indoor unit (1) and the outdoor unit (2), respectively.
b) (12c) (12d) (18a) (18b) (18c) (18d)
There are two independent AC power lines (19) and (20) and two independent serial signal lines (21) and (32) provided separately between (1) and the outdoor unit (2). And are connected by.

The first AC power supply line (19)
This is the same as in the embodiment. On the indoor unit (1) side of the second AC power supply line (20), the second terminal (12b) is connected to the AC power supply (22).
It is connected to the. Outdoor unit of the second AC power line (20)
On the (2) side, the second terminal (18b) is connected to the inverter power supply circuit (13). The first serial signal line (2
On the indoor unit (1) side of 1), the emitter of the transmitting PT (26b) is grounded. The outdoor unit (2) side of the signal line (21) is the same as in the first embodiment. Regarding the second serial signal line (32), the fourth of the indoor unit (1) and the outdoor unit (2)
The terminals (12d) and (18d) are connected by an electric wire (32a). At the indoor unit (1) side of the signal line (32), the fourth terminal
(12d) is connected to a 12V DC power supply (33). On the outdoor unit (2) side of the signal line (32), the fourth terminal (18d) is a break contact of the transmission PT (27b) and the inspection relay (15).
(15b). Then, as described above, the second signal line (32) and the first signal line (21) constitute a DC loop circuit.

The other points are the same as those of the first embodiment, and the erroneous wiring can be inspected almost in the same manner.

[0073]

According to the air conditioner of the present invention, as described above , the AC power can be supplied to the outdoor unit only by adding a few parts and a microcomputer program constituting the indoor unit control circuit.
Before applying AC power, when AC power is applied to the indoor unit ,
Inspection of wiring is easy and regardless of the mode of incorrect wiring
I can do it for sure. Therefore, at the time of installation work of the air conditioner, it is possible to control so that no AC power is applied to the outdoor unit even if the wiring is erroneously made, and there is no breakage of components and no rise in temperature, which is very safe. Further, there is no need to use a protection circuit at the time of erroneous wiring or a component using a high withstand voltage unlike a conventional circuit having no erroneous wiring inspection circuit, so that a change in cost of the control circuit can be reduced. In addition, since an erroneous wiring display can be performed, the cause of the malfunction can be quickly identified at the time of erroneous wiring, and prompt action can be taken.

[Brief description of the drawings]

FIG. 1 is an electric block diagram of a main part of an air conditioner according to a first embodiment of the present invention.

FIG. 2 is an electric circuit diagram showing a main part of FIG.

FIG. 3 is a flowchart illustrating an example of processing of an indoor unit control circuit at the time of wiring inspection.

FIG. 4 is an explanatory diagram showing types of miswiring modes.

FIG. 5 is an electric block diagram of a main part of an air conditioner according to a second embodiment of the present invention.

6 is an electric circuit diagram showing a main part of FIG.

FIG. 7 is an electric circuit diagram of a main part of an air conditioner according to a third embodiment of the present invention.

FIG. 8 is an electric circuit diagram of a main part of an air conditioner showing a fourth embodiment of the present invention.

[Explanation of symbols]

(1) Indoor unit (2) Outdoor unit (3) DC power supply circuit (4) DC power supply circuit for serial signal transmission (5) Relay drive circuit (6) Main relay contact (7) Operation circuit (8) Display circuit (9 ) Serial signal transmission / reception circuit (11) Indoor unit control circuit (13) Power supply circuit for outdoor unit inverter (14) Serial signal transmission / reception circuit (15) Inspection relay (15b) Break contact (inspection switch element) (17) Outdoor unit Control circuit (19) 1st AC power line (20) 2nd AC power line (21) Serial signal line (22) AC power (26) Photocoupler (transmitting element) for transmission (26a) LED for transmission (input for transmission) (26b) Transmission phototransistor (transmission switch element) (27) Transmission photocoupler (transmission element) (27a) Transmission LED (transmission input element) (27b) Transmission phototransistor (transmission switch element) (28) Receiving photocoupler (receiving element) (28a) Receiving LED (Input element for reception) (28b) Phototransistor for reception (switch element for reception) (29) Photocoupler for reception (reception element) (29a) LED for reception (input element for reception) (29b) Phototransistor for reception (reception Switch element) (30) Positive characteristic semiconductor element (inspection switch element) (32) Serial signal line (ZD3) Zener diode (inspection switch element)

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F24F 11/02

Claims (7)

(57) [Claims] An indoor unit and an outdoor unit having a common AC power line are provided, and a space between the indoor unit and the outdoor unit is provided separately from two AC power lines, one of which is shared with a DC power line. Connected by a single serial signal line,
The DC power supply line and the serial signal line, which are shared with the AC power supply line, form a serial signal transmission circuit including a DC loop circuit extending between the indoor unit and the outdoor unit, and a direction from the indoor unit to the outdoor unit and from the outdoor unit to the indoor unit. DC power is applied to the DC power line shared with the AC power line during the inspection mode before applying AC power to the outdoor unit in an air conditioner that transmits serial signals in both directions Then, after a predetermined time, by examining whether or not a DC loop circuit of the serial signal transmission circuit has been formed, the presence or absence of incorrect wiring between the indoor unit and the outdoor unit is inspected. An air conditioner which displays an incorrect wiring and prohibits the application of AC power to an outdoor unit. 2. An indoor unit is provided with a main relay contact for controlling application of AC power to the outdoor unit, a DC power supply circuit, an operation circuit, a display circuit, a serial signal transmission / reception circuit, and an indoor unit control circuit. The power supply circuit, the serial signal transmission / reception circuit, and the outdoor unit control circuit are provided in the unit, and the serial signal transmission / reception circuit of the indoor unit and the outdoor unit are respectively provided with a transmission element and a reception switch element including a transmission input element and a transmission switch element. A receiving element comprising an input element and a receiving switch element is provided, and a receiving input element and a transmitting switch element of a serial signal transmitting / receiving circuit of an indoor unit, a transmitting switch element and a receiving input element of an outdoor unit, an AC power supply line A DC loop circuit of a serial signal transmission circuit is formed by the DC power supply line and the serial signal line shared with the Test switch element is connected in parallel to the transmission switch element of the serial signal transmission and reception circuit,
In the inspection mode, the DC loop circuit of the serial signal transmission circuit is formed a predetermined time after the indoor unit control circuit closes the transmission switch element of the serial signal transmission / reception circuit of the indoor unit with the inspection switch element closed. Check if there is a DC loop circuit, determine that there is no incorrect wiring, if no DC loop circuit is formed, determine that there is incorrect wiring, and if there is a wrong wiring, check the display circuit for incorrect wiring. In addition to displaying, even if the operation is performed, the main relay contact is kept open, the application of AC power to the outdoor unit is prohibited, and if there is no incorrect wiring, the operation is performed An AC power supply is applied to the outdoor unit, and while the AC is applied to the outdoor unit and power is supplied to the outdoor unit control circuit, the inspection switch element is configured to be opened. 1 of the air conditioner. 3. An indoor unit and an outdoor unit having a common AC power supply line, wherein two AC power supply lines and two separate serial signal lines are provided between the indoor unit and the outdoor unit. And a serial signal transmission circuit including a DC loop circuit extending between the indoor unit and the outdoor unit by the two serial signal lines. The serial signal transmission circuit is formed in the direction from the indoor unit to the outdoor unit and from the outdoor unit to the indoor unit. In an air conditioner that transmits signals in both directions, in the inspection mode before applying AC power to the outdoor unit, a predetermined time after applying DC power to the DC power line connected to the serial signal line Later, by examining whether the DC loop circuit of the serial signal transmission circuit is formed, inspect the presence or absence of incorrect wiring between the indoor unit and the outdoor unit,
If there is a mis-wiring, it will be displayed,
An air conditioner characterized in that application of AC power to an outdoor unit is prohibited. 4. An indoor unit is provided with a main relay contact for controlling application of AC power to the outdoor unit, a DC power supply circuit, an operation circuit, a display circuit, a serial signal transmission / reception circuit, and an indoor unit control circuit. The power supply circuit, the serial signal transmission / reception circuit, and the outdoor unit control circuit are provided in the unit, and the serial signal transmission / reception circuit of the indoor unit and the outdoor unit are respectively provided with a transmission element and a reception switch element including a transmission input element and a transmission switch element. A reception element comprising an input element and a reception switch element is provided; a reception input element and a transmission switch element of a serial signal transmission / reception circuit of the indoor unit; a transmission switch element and a reception input element of the outdoor unit;
The serial signal line forms a DC loop circuit of the serial signal transmission circuit, and the inspection switch element is connected in parallel to the transmission switch element of the serial signal transmission / reception circuit of the outdoor unit. But,
In a state where the test switch element is closed, a predetermined close the transmission switch element of the serial signal transmission and reception circuit of the indoor unit
After a time, it is determined whether or not the DC loop circuit of the serial signal transmission circuit is formed.If the DC loop circuit is formed, there is no miswiring, and if the DC loop circuit is not formed, it is determined that there is miswiring, If there is a miswiring, the display circuit will indicate the miswiring and keep the main relay contacts open even if the operation is performed, prohibiting the application of AC power to the outdoor unit, In the case of no wiring, when the driving operation is performed, AC power is applied to the outdoor unit, and while the AC power is applied to the outdoor unit and the outdoor unit control circuit is energized, the inspection switch element is not operated. The air conditioner according to claim 3, wherein the air conditioner is opened. 5. The inspection switch element is a break contact of a relay connected to the outdoor unit control circuit.
5. The air conditioner according to claim 2, wherein the air conditioner is turned off when the outdoor unit control circuit is not energized, and is turned on while the outdoor unit control circuit is energized. 6. The air conditioner according to claim 2, wherein the inspection switch element is a positive characteristic semiconductor element attached to a heat sink of a power supply circuit of the outdoor unit. 7. The inspection switch element is a Zener diode, and the indoor unit control circuit switches the output of the DC power supply circuit to a voltage higher than the breakdown voltage of the Zener diode in the inspection mode. 5. The air conditioner according to claim 2, wherein the output is switched to a voltage lower than the breakdown voltage of the Zener diode.