JPH06193979A - Air conditioner - Google Patents

Abstract

PURPOSE:To commonly provide an indoor controller irrespective of a driving mode of a compressor by providing a converter for converting an operation frequency command to be generated from an indoor controller to ON/OFF operation commands to a compressor to be driven by a commercial power source. CONSTITUTION:A difference of an indoor temperature to be sensed by an indoor temperature sensor 8 at the time of cooling and a set temperature is obtained as air conditioning load, and an operating frequency command corresponding to the load is read from a RAM of a microcomputer 20. The frequency command is sent to a converter 40. An operation of an outdoor fan is started. The command sent to the converter 40 is then converted to ON/OFF operation command, A power relay 21 is repeatedly turned ON, OFF in response to the ON/OFF command, and an electric circuit to a compressor motor 1M is switched. Predetermined conditions are previously decided for conversion from the frequency command to the ON/OFF command, and the higher the frequency is, larger command signal having large ON/OFF duty is generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a split type air conditioner comprising an outdoor unit and an indoor unit.

[0002]

2. Description of the Related Art There are two types of air conditioners: a type in which an inverter-driven variable capacity compressor is installed in an outdoor unit and a type in which a commercial power source-driven compressor is installed in an outdoor unit.

In the type equipped with an inverter-driven variable capacity compressor, the difference between the room temperature and the set temperature is required.
The operating frequency (= output frequency of the inverter circuit) is controlled according to the difference. In a type equipped with a compressor driven by a commercial power source, the indoor temperature is compared with a set temperature, and the operation of the compressor is on / off controlled according to the comparison result.
A dedicated indoor controller is provided for each of these different types.

[0004]

Providing different indoor controllers for each type requires a lot of time and labor for designing and developing, causes an increase in the number of parts, and leads to an increase in cost.

The present invention takes the above circumstances into consideration,
The purpose is to make it possible to use a common indoor controller regardless of the drive mode of the compressor, which can reduce the time and labor required for designing and developing, and reduce the number of parts. An object is to provide an air conditioner that can reduce costs.

[0006]

An air conditioner according to claim 1 of the present invention includes an outdoor unit having an inverter-driven or commercial power source-driven compressor and an outdoor heat exchanger, and an indoor unit having an indoor heat exchanger. , An indoor controller installed in this indoor unit that issues an operating frequency command to the inverter-driven compressor, and an operating frequency command that is installed in the indoor unit as needed to convert the operating frequency command into an on / off operating command for the commercial power supply driven compressor And a converter for

An air conditioner according to a second aspect of the invention is an outdoor unit having an inverter-driven or commercial power source-driven compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, and an inverter drive provided in the indoor unit. Of the indoor controller that issues an operating frequency command to the compressor, and an operating frequency command that is externally connected to the indoor unit and the outdoor unit as necessary, converts the operating frequency command into an on / off operation command for the commercial power source driven compressor, and turns it on. And a converter that controls energization to the compressor according to the off operation command.

[0008]

In the air conditioner of the first aspect, when the compressor of the outdoor unit is driven by an inverter, the compressor is controlled by the operating frequency command issued from the indoor controller. When the compressor of the outdoor unit is driven by the commercial power source, the converter provided in the indoor unit converts the operation frequency command issued from the indoor controller into the on / off operation command.

In the air conditioner of the second aspect, when the compressor of the outdoor unit is driven by an inverter, the compressor is controlled by an operating frequency command issued from the indoor controller. When the compressor of the outdoor unit is driven by commercial power, the converter externally connected to the indoor unit and the outdoor unit converts the operating frequency command issued from the indoor controller into the on / off operating command by the converter, and The energization of the compressor is controlled according to the on / off operation command.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. First, the structure of the refrigeration cycle is shown in FIG.

An outdoor heat exchanger 3 is connected to the discharge port of the compressor 1 via a four-way valve 2, and an indoor heat exchanger 5 is connected to the outdoor heat exchanger 3 via a pressure reducer, for example, an expansion valve 4. .
The indoor heat exchanger 5 is connected to the suction port of the compressor 1 via the four-way valve 2.

That is, the refrigerant discharged from the compressor 1 flows in the direction of the solid line arrow to form a cooling cycle, and the outdoor heat exchanger 3 functions as a condenser and the indoor heat exchanger 5 functions as an evaporator. The four-way valve 2 is switched and the refrigerant discharged from the compressor 1 flows in the direction of the dashed arrow in the figure to form a heating cycle, and the indoor heat exchanger 5 functions as a condenser and the outdoor heat exchanger 3 functions as an evaporator.

An outdoor fan 6 is provided near the outdoor heat exchanger 3. An indoor fan 7 and an indoor temperature sensor 8 are provided near the indoor heat exchanger 5. A heat exchanger temperature sensor 9 is attached to the indoor heat exchanger 5. In the case of the outdoor unit A ₁ described later, the heat exchanger temperature sensor 10 is attached to the outdoor heat exchanger 3.

An outdoor unit A has at least the compressor 1, the four-way valve 2, the outdoor heat exchanger 3, the expansion valve 4, and the outdoor fan 6. An indoor unit B has at least an indoor heat exchanger 5, an indoor fan 7, an indoor temperature sensor 8, and a heat exchanger temperature sensor 9. The control circuit is shown in FIG. FIG. 3 shows an example in which an inverter drive type outdoor unit A ₁ having a variable capacity compressor is adopted as the compressor ₁ . The indoor unit B is connected to the commercial AC power supply 11, and the outdoor unit A ₁ of the inverter drive type is connected to the indoor unit B by a crossover connection.

The indoor unit B has a microcomputer 20 as an indoor controller. An indoor temperature sensor 8, a heat exchanger temperature sensor 9, a power relay 21, and a serial signal transmitting / receiving circuit 22 are connected to the microcomputer 20.

The power relay 21 is inserted and connected to a power supply line ACL connected from the power supply 11 to the first and second terminals of the terminal board 23, and opens and closes the power supply line ACL in response to a command from the microcomputer 20.

The serial signal transmission / reception circuit 22 converts the command of the microcomputer 20 into a serial signal synchronized with the power supply voltage and sends the serial signal to the serial signal line SL, and also converts the serial signal input from the serial signal line SL into data. , It's a microcomputer 2
Supply to 0. The serial signal line SL is connected to the terminal board 23.
It is connected to the 3rd terminal of. Microcomputer 20
Has a CPU and a RAM, and has the following main functional means.

[1] A cooling command or a heating command corresponding to an operation mode (cooling / heating) set by a remote control type operation device (hereinafter referred to as a remote controller; not shown) is read from the RAM, and is read out as a serial signal. Means for sending to the transmitting / receiving circuit 22.

[2] The operation start command and operation stop command corresponding to the operation start operation and operation stop operation of the remote controller
Means for storing in AM and sending it to the serial signal transmitting / receiving circuit 22. [3] Power relay 2 according to the operation start operation of the remote controller
A means for turning on 1 and turning off the power relay 21 in response to an operation to stop the operation.

[4] Each of the room temperature Ta detected by the room temperature sensor 8 and the set temperature Ts set by the remote controller is stored in the RAM, and the difference (= Ta-T).
s) is obtained as the air conditioning load, the operating frequency command corresponding to the air conditioning load is stored in the RAM, and is sent to the serial signal transmitting / receiving circuit 22.

[5] Heat exchanger temperature sensor 9 during cooling operation
The detected temperature (evaporator temperature) Te of the
Means for sending a compressor stop command to the serial signal transmitting / receiving circuit 22 when the temperature becomes 0 ° C. or less. This is to prevent freezing of the indoor heat exchanger 5.

On the other hand, the outdoor unit A ₁ has a microcomputer 30 as an outdoor controller. Relays 31, 32, an inverter circuit 33, a serial signal transmission / reception circuit 34, and the heat exchanger temperature sensor 10 are connected to the microcomputer 30. Also, the outdoor unit A ₁
Has a terminal plate 35, the first terminal of the terminal plate 35, 2
No. 3 and No. 3 terminals are the terminal boards 23 in the indoor unit B.
No. 1 terminal, No. 2 terminal, and No. 3 terminal.

The relay 31 is inserted into and connected to a power supply line ACL connected from the first and second terminals of the terminal plate 35 to the four-way valve 2, and opens and closes the power supply line ACL in response to a command from the microcomputer 30. Relay 32
Are connected and connected to the same power supply line ACL, and the power supply line ACL is opened / closed in response to a command from the microcomputer 30.

The inverter circuits 33 have the same power supply line A.
The voltage of CL is rectified, and it is used by the microcomputer 30.
Converted to alternating current of frequency (and voltage) according to
Output. This output becomes drive power for the compressor motor 1M.

The serial signal transmission / reception circuit 34 converts the command of the microcomputer 30 into a serial signal synchronized with the power supply voltage and sends it out to the serial signal line SL, and also converts the serial signal input from the serial signal line SL into data. , It's a microcomputer 3
Supply to 0. The serial signal line SL is connected to the terminal board 35.
It is connected to the 3rd terminal of. Microcomputer 30
Has a CPU and a RAM, and has the following main functional means. [1] A means for switching on the four-way valve 2 by turning on the relay 31 when the heating command is received by the serial signal transmitting / receiving circuit 34.

[2] When the operation start command is received by the serial signal transmitting / receiving circuit 34, the relay 32 is turned on to operate the outdoor fan motor 6M and the inverter circuit 33 is driven to operate the compressor motor 1M. means.

[3] Means for controlling the output frequency of the inverter circuit 33 (hereinafter referred to as the operating frequency F) based on the operating frequency command received by the serial signal transmitting / receiving circuit 34. [4] A means for stopping the driving of the inverter circuit 33 and stopping the operation of the compressor motor 1M when the serial signal transmission / reception circuit 34 receives the compressor stop command during the cooling operation. This is to prevent freezing of the indoor heat exchanger 5.

[5] When the operation stop command is received by the serial signal transmitting / receiving circuit 34, the relay 32 is turned off to stop the operation of the outdoor fan motor 6M, and the driving of the inverter circuit 33 is stopped to stop the compressor motor. Means to stop the operation of 1M.

[6] Heat exchanger temperature sensor 1 during heating operation
When the detection temperature Te of 0 (evaporator temperature) Te becomes 0 ° C. or lower,
Means for switching off the four-way valve 2 by turning off the relay 31.
This switching of the four-way valve 2 is for forming a defrost cycle for the outdoor heat exchanger 3. The operation will be described.

When the cooling operation mode and the set temperature Ts are determined by the remote controller and the operation for starting the operation is performed, the power relay 21 is turned on, and at the same time, the indoor unit B sends a predetermined command to the outdoor unit A ₁ to send a compressor. 1 and the outdoor fan 6 are started to operate. That is, the refrigerant discharged from the compressor 1 flows in the direction indicated by the solid arrow in FIG. 2 to form a cooling cycle, the outdoor heat exchanger 3 functions as a condenser, and the indoor heat exchanger 5 functions as an evaporator. Is cooled.

During this cooling operation, the difference between the indoor temperature Ta detected by the indoor temperature sensor 8 and the set temperature Ts is obtained as an air conditioning load (= cooling load), and the operating frequency command corresponding to the air conditioning load is given to the indoor unit. Outdoor unit A from B
Sent to ₁ . Based on this operating frequency command, the compressor 1
The operating frequency F of is controlled. That is, the cooling capacity corresponding to the air conditioning load is exhibited.

During cooling, drainage may occur in the indoor heat exchanger 5 functioning as an evaporator, which may freeze on the surface of the indoor heat exchanger 5. In this case, the heat exchange area is reduced and the cooling capacity is reduced.

Therefore, the temperature Te of the indoor heat exchanger 5 is detected by the heat exchanger temperature sensor 9, and when the detected temperature Te falls below 0 ° C., it is determined that the indoor heat exchanger 5 is frozen. Below, a compressor stop command is sent from the indoor unit B to the outdoor unit A ₁ . By this command, the operation of the compressor 1 is stopped and the freezing of the indoor heat exchanger 5 is released.

When the heating operation mode and the set temperature Ts are determined by the remote controller and the operation is started, a predetermined command is sent from the indoor unit B to the outdoor unit A ₁ to switch the four-way valve 2 and the compressor 1 And the operation of the outdoor fan 6 is started. That is, the refrigerant discharged from the compressor 1 flows in the direction indicated by the broken line arrow in FIG. 2 to form a heating cycle, and the indoor heat exchanger 5 becomes the condenser and the outdoor heat exchanger 3
Functions as an evaporator and heats the room.

During the heating operation, the difference between the set temperature Ts and the indoor temperature Ta detected by the indoor temperature sensor 8 is obtained as an air conditioning load (= heating load), and the operating frequency command corresponding to the air conditioning load is given to the indoor unit. Outdoor unit A from B
Sent to ₁ . Based on this operating frequency command, the compressor 1
The operating frequency F of is controlled. That is, the heating capacity corresponding to the air conditioning load is exhibited. Further, during heating, frost is gradually formed on the surface of the outdoor heat exchanger 3 functioning as an evaporator, and if it is left as it is, the heat exchange area is reduced and the heating capacity is lowered.

Therefore, the temperature Te of the outdoor heat exchanger 3 is detected by the heat exchanger temperature sensor 10, and when the detected temperature Te falls below a predetermined value, the outdoor heat exchanger 3 is said to be frosted. Under the judgment, the defrosting command is sent from the indoor unit B to the outdoor unit A ₁ .

When the defrosting command is issued, the four-way valve 2 is returned to form the defrosting cycle, and the high temperature refrigerant discharged from the compressor 1 is supplied to the outdoor heat exchanger 3 as it is. Thereby, the outdoor heat exchanger 3 is defrosted. Next, FIG. 1 shows an example in which a commercial power supply type outdoor unit A ₂ is connected to the indoor unit B by a crossover connection.

In this case, the converter C is provided in the indoor unit B, and the conversion circuit 40 of the converter C is connected to the RAM of the microcomputer 20 and the power relay 21. One line of the power supply line ACL is 3 of the terminal board 23.
No. 4 terminal and No. 4 terminal, and the four-way valve driver 41 and the outdoor fan driver 42 of the converter C are respectively inserted and connected to the connection lines. The connection of the serial signal line between the serial signal transmitting / receiving circuit 22 and the third terminal is disconnected. There is no change in the specifications of the microcomputer 20.

The four-way valve driver 41 opens and closes the connection line (power supply line ACL) to the 4th terminal in response to a command from the conversion circuit 40. The outdoor fan driver 42 opens and closes the connection line (power supply line ACL) to the third terminal in response to a command from the conversion circuit 40. The conversion circuit 40 is connected to the RAM of the microcomputer 20 and includes the following functional means. [1] Four-way valve driver 4 when receiving a heating command from RAM
1 is operated and the connection line to the 4th terminal (power line A
CL) means for conducting.

[2] During heating operation, the temperature Ta detected by the indoor temperature sensor 8 and the temperature (condenser temperature) Tc of the outdoor heat exchanger 3 detected by the heat exchanger temperature sensor 9 are read from the RAM, and the difference ( = Ta-Tc), and when the difference exceeds a predetermined value, the operations of the four-way valve driver 41 and the outdoor fan driver 42 are stopped, and the connection line (power supply line ACL) to the 4th and 3rd terminals is cut off. means. [3] A means for receiving an operating frequency command from the RAM and converting it into an on / off operating command. [4] A means for controlling on / off of the power relay 21 and the outdoor fan driver 42 according to the converted on / off operation command.

On the other hand, the outdoor unit A ₂ has a terminal plate 50, and the first terminal, the second terminal, the third terminal, and the fourth terminal of the terminal plate 50 are the first terminals of the terminal plate 23 in the indoor unit B. It is connected to the terminal, the second terminal, the third terminal, and the fourth terminal, respectively.

The compressor motor 1M is connected to the first and second terminals of the terminal board 50 through the power supply line ACL. The outdoor fan motor 6M is connected to the 2nd terminal and the 3rd terminal of the terminal board 50 through the power supply line ACL. The four-way valve 2 is connected to terminals 2 and 4 of the terminal board 50. The operation will be described.

When the cooling operation mode and the set temperature Ts are set by the remote controller and the operation for starting the operation is performed, the power relay 21 is turned on, the energization path for the compressor motor 1M is formed, and the operation of the compressor 1 is started. .

That is, the refrigerant discharged from the compressor 1 flows in the direction shown by the solid arrow in FIG. 2 to form a cooling cycle, the outdoor heat exchanger 3 functions as a condenser, and the indoor heat exchanger 5 functions as an evaporator. To do.

During this cooling operation, the difference between the indoor temperature Ta detected by the indoor temperature sensor 8 and the set temperature Ts is obtained as the air conditioning load (= cooling load), and the operating frequency command corresponding to the air conditioning load is given by the microcomputer. 20 RAM
Read from. The read operating frequency command is sent to the converter 40 as it is.

When the operating frequency command is sent to the converter 40, the outdoor fan driver 42 is turned on, an energization path for the outdoor fan motor 6M is formed, and the operation of the outdoor fan 6 is started.

The operating frequency command sent to the converter 40 is converted into an on / off operating command there. The power relay 21 is repeatedly turned on and off in response to the on / off operation command, and the energization path for the compressor motor 1M is opened / closed. This opening / closing controls the capacity of the compressor 1.

The conditions shown in FIG. 4 are predetermined for the conversion from the operating frequency command to the on / off operating command. As the operating frequency F is higher, a command signal with a larger on / off duty is issued.

Therefore, for example, the air conditioning load is large,
When the operating frequency F is set to a high value, an ON / OFF operation command with a large ON / OFF duty is issued, the energization ON period to the compressor 1 is lengthened, and the capacity of the compressor 1 is enhanced. As the cooling progresses and the air conditioning load decreases, the operating frequency F
When becomes low, an ON / OFF operation command with a small ON / OFF duty is issued, the ON period of the power supply to the compressor 1 is shortened, and the capacity of the compressor 1 is lowered. That is, it is possible to control the capacity of the compressor 1 of the commercial power source drive type.

When freezing of the indoor heat exchanger 5 is detected and a compressor stop command is sent from the microcomputer 20 to the converter 40, the power relay 21 is turned off. When the power relay 21 is turned off, the power supply to the compressor motor 1M is cut off, the operation of the compressor 1 is stopped, and the freezing of the indoor heat exchanger 5 is released.

In the heating operation mode, a heating command is sent from the microcomputer 20 to the converter 40, the four-way valve driver 41 is turned on, and the four-way valve 2 is switched. As a result, a heating cycle is formed.

During this heating, in the converter 40, the temperature Ta detected by the indoor temperature sensor 8 and the temperature (condenser temperature) Tc of the indoor heat exchanger 5 detected by the heat exchanger temperature sensor 9 are stored in the RAM.
And the difference (= Ta−Tc) is obtained.

The condenser temperature Tc normally does not change so much because the compressor 1 has a fixed capacity, but when the outdoor heat exchanger 3 is frosted, the condenser temperature Tc greatly decreases as the pumping heat amount decreases. To do. That is, when the outdoor heat exchanger 3 is frosted, the temperature difference increases above a predetermined value. At this time, in the converter 40, the four-way valve driver 41 and the outdoor fan driver 42 are turned off based on the determination that the outdoor heat exchanger 3 has frosted. When the four-way valve driver 41 is turned off, the power supply path to the four-way valve 2 is cut off. As a result, the four-way valve 2 returns to form a defrost cycle, the high-temperature refrigerant discharged from the compressor 1 is directly supplied to the outdoor heat exchanger 3, and the outdoor heat exchanger 3 is defrosted.

Thus, by simply adding the converter C to the indoor unit B, the outdoor unit A of the commercial power source drive type
_It is possible to adopt ₂ . Therefore, the microcomputer 20 of the indoor unit B can be shared regardless of the type of the outdoor unit. This commonality can reduce the time and labor required for design and development, reduce the number of parts, and eventually reduce the cost.

In the above embodiment, the outdoor unit A ₂
In adopting, the converter C is provided in the indoor unit B, but the converter C may be externally connected to the indoor unit B and the outdoor unit A ₂ as shown in FIG.

In this case, the converter 11 has a relay circuit 43 in addition to the conversion circuit 40, the four-way valve driver 41, and the outdoor fan driver 42, and the relay 43 has the terminal plate 23,
It is inserted and connected to the crossover 11 for the power supply line between the first terminals 50.

In the connecting wire 11 between the first terminals, a power supply line AC is provided at a position closer to the indoor unit B than the relay 43.
The 3rd terminal and the 4th terminal of the terminal board 30 are respectively connected via L. The four-way valve driver 41 and the outdoor fan driver 42 of the converter C are respectively connected to these connection lines.

The serial signal transmission / reception circuit 22 of the indoor unit B is connected to the terminal board 23 through the serial signal line SL.
The conversion circuit 40 is connected to the third terminal through the serial signal line SL. Conversion circuit 40
Has the following functional means. [1] A means for converting the serial signal input from the serial signal line SL into data and fetching various commands. [2] When the heating command is taken in, the four-way valve driver 41 is operated, and the connection line to the fourth terminal (power supply line AC
L) means for conducting.

[3] During heating operation, the temperature Ta detected by the indoor temperature sensor 8 and the temperature (condenser temperature) Tc of the outdoor heat exchanger 3 detected by the heat exchanger temperature sensor 9 are read from the RAM, and the difference ( = Ta-Tc), and when the difference exceeds a predetermined value, the operations of the four-way valve driver 41 and the outdoor fan driver 42 are stopped, and the connection line (power supply line ACL) to the 4th and 3rd terminals is cut off. means. [4] A means for converting the operating frequency command into an on / off operating command when the operating frequency command is taken in. [5] A means for controlling on / off of the power relay 21 and the outdoor fan driver 42 according to the converted on / off operation command. The operation will be described.

When the cooling operation mode and the set temperature Ts are set by the remote controller and the operation for starting the operation is performed, the power relay 21 is turned on. At the same time, an operation start command is sent from the indoor unit B to the converter C and the relay 43 is turned on.
As a result, an energization path for the compressor motor 1M is formed, the operation of the compressor 1 is started, and the cooling operation is executed.

During this cooling operation, the operating frequency command corresponding to the air conditioning load is sent from the indoor unit B to the converter C.
When the operating frequency command is sent to the converter 40, the outdoor fan driver 42 is turned on, an energization path for the outdoor fan motor 6M is formed, and the operation of the outdoor fan 6 is started.

The operating frequency command sent to the converter 40 is converted into an on / off operating command there. The relay 43 is repeatedly turned on and off in response to the on / off operation command, and the energization path for the compressor motor 1M is opened / closed.
This opening / closing controls the capacity of the compressor 1. The functions of freeze prevention, heating operation, and defrosting are the same as those in the case of FIG.

As described above, the commercial power supply type outdoor unit A ₂ can be employed only by externally connecting the converter C. Therefore, the microcomputer 20 of the indoor unit B can be shared regardless of the type of the outdoor unit. This commonality can reduce the time and labor required for design and development, reduce the number of parts, and eventually reduce the cost. In particular, since it is an external type, the converter C can be easily attached and detached, and the work efficiency at the installation site can be improved.

[0064]

As described above, according to the present invention, the converter for converting the operating frequency command issued from the indoor controller into the on / off operating command for the compressor driven by the commercial power source is provided. The indoor controller can be made common regardless of the drive form of the air conditioner, which can reduce the time and labor required for design and development, reduce the number of parts, and eventually reduce the cost. Can be provided.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a control circuit when a commercial power supply type outdoor unit is connected to an indoor unit according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a refrigeration cycle of the same embodiment.

FIG. 3 is a configuration diagram of a control circuit when an inverter drive type outdoor unit is connected to the indoor unit in the embodiment.

FIG. 4 is a diagram showing a conversion condition from an operating frequency command to an on / off operating command.

FIG. 5 is a configuration diagram of a control circuit when a modification of the converter according to the embodiment is adopted.

[Explanation of symbols]

A ₁ ... Inverter drive type outdoor unit, A ₂ ... Commercial power source drive type outdoor unit, C ... Converter, 1 ... Compressor, 3 ... Outdoor heat exchanger, 5 ... Indoor heat exchanger, 20 ... Microcomputer ( Indoor controller).

Claims (2)

[Claims] 1. An outdoor unit having an inverter-driven or commercial power source-driven compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, and an operating frequency command for an inverter-driven compressor provided in the indoor unit. An air conditioner comprising: an indoor controller that emits a signal; and a converter that is provided in the indoor unit as necessary and that converts the operating frequency command into an on / off operating command for a compressor driven by a commercial power supply. Machine. 2. An outdoor unit having an inverter-driven or commercial power source-driven compressor and an outdoor heat exchanger, an indoor unit having an indoor heat exchanger, and an operating frequency command for an inverter-driven compressor provided in the indoor unit. And an indoor controller that emits a signal, which is externally connected to the indoor unit and the outdoor unit as necessary, converts the operation frequency command into an on / off operation command for a commercial power supply driven compressor, and responds to the on / off operation command. An air conditioner characterized by comprising a converter for controlling energization to a compressor.