阅读说明：本技术 空调器和中转装置及控制空调室内外机通信的方法 (Air conditioner, transfer device and method for controlling communication between indoor unit and outdoor unit of air conditioner ) 是由 张新建 牟宗娥 赵海潞 于 2021-07-05 设计创作，主要内容包括：本发明公开了一种空调器和中转装置以及控制空调室内外机通信的方法,其中,空调器包括室内机、室外机和中转装置,所述室内机包括室内控制器和室内电流环通信电路,所述室内电流环通信电路与所述室内控制器连接；所述室外机包括室外控制器和室外电流环通信电路,所述室外电流环通信电路与所述室外控制器连接；所述中转装置与所述室内电流环通信电路和所述室外电流环通信电路分别连接,用于转发所述室内控制器与所述室外控制器之间的通信信息。本发明的空调器和中转装置,可以保证通信信息的有效、可靠地收发,避免通信信息持续衰减,增长了电流环通信的距离,适用于室内外机距离较远的情况。(The invention discloses an air conditioner and a transfer device and a method for controlling communication between an indoor unit and an outdoor unit of the air conditioner, wherein the air conditioner comprises the indoor unit, the outdoor unit and the transfer device, the indoor unit comprises an indoor controller and an indoor current loop communication circuit, and the indoor current loop communication circuit is connected with the indoor controller; the outdoor unit comprises an outdoor controller and an outdoor current loop communication circuit, and the outdoor current loop communication circuit is connected with the outdoor controller; the transfer device is connected with the indoor current loop communication circuit and the outdoor current loop communication circuit respectively and is used for transferring communication information between the indoor controller and the outdoor controller. The air conditioner and the transfer device can ensure effective and reliable receiving and sending of communication information, avoid continuous attenuation of the communication information, increase the distance of current loop communication, and are suitable for the condition that the distance between an indoor unit and an outdoor unit is long.)

1. An air conditioner, comprising:

the indoor unit comprises an indoor controller and an indoor current loop communication circuit, and the indoor current loop communication circuit is connected with the indoor controller;

the outdoor unit comprises an outdoor controller and an outdoor current loop communication circuit, and the outdoor current loop communication circuit is connected with the outdoor controller;

and the transfer device is respectively connected with the indoor current loop communication circuit and the outdoor current loop communication circuit and is used for transferring communication information between the indoor controller and the outdoor controller.

2. The air conditioner according to claim 1, wherein the relay device comprises:

a housing;

a first electrical connector disposed within the housing connected to the indoor current loop communication circuit;

a second electrical connection disposed within the housing connected to the outdoor current loop communication circuit;

the control unit is connected with the first electric connecting piece and the second electric connecting piece respectively and used for forwarding the communication information.

3. Air conditioner according to claim 2, characterized in that the control unit is specifically adapted to, when forwarding the communication information,

receiving communication information of a sender, and forwarding the communication information to a receiver after the communication information is confirmed to be complete, or sending communication fault information to the indoor controller to control the indoor unit to perform fault prompt when the communication information is confirmed to be incomplete;

wherein one of the indoor controller and the outdoor controller serves as the sender and the other serves as the receiver.

4. The air conditioner according to claim 3, wherein the transfer device further comprises:

the switching power supply is connected with the first electric connecting piece or the second electric connecting piece and is used for converting power supply voltage in the current loop communication circuit into required voltage to supply power to the control unit;

the voltage detection unit is arranged in the shell and used for detecting a voltage signal of the switching power supply;

the control unit is further connected with the voltage detection unit and the switching power supply and used for judging whether a communication fault exists on a connecting line of the transfer device according to the voltage signal.

5. A relay device, for use in current loop communication, the relay device comprising:

a housing;

a first electrical connector disposed within the housing;

a second electrical connector disposed within the housing;

and the control unit is respectively connected with the first electric connecting piece and the second electric connecting piece and is used for forwarding communication information of current loop communication between the sender and the receiver.

6. The relay device according to claim 5, wherein the control unit is specifically configured to, when forwarding the communication information, receive the communication information of the sender, and after confirming that the communication information is complete, forward the communication information to the receiver, or when confirming that the communication information is incomplete, send communication failure information to prompt a failure.

7. The relay device according to claim 5, wherein said relay device further comprises:

the switching power supply and the first electric connecting piece or the second electric connecting piece are used for converting power supply voltage in the current loop communication circuit into required voltage to supply power to the control unit;

the voltage detection unit is arranged in the shell and used for detecting and detecting a voltage signal of the switching power supply;

the control unit is also connected with the voltage detection unit and the switching power supply and used for judging whether a communication fault exists on the connection line of the transfer device according to the voltage signal.

8. The transfer device of claim 5, wherein the first electrical connection further comprises a first ground terminal and the second electrical connection further comprises a second ground terminal.

9. A method for controlling communication between indoor and outdoor units of an air conditioner is characterized by comprising a transfer device for transferring communication information between the indoor and outdoor units, wherein the method comprises the following steps of;

receiving communication information of a sender;

judging the integrity of the communication information;

if the communication information is determined to be complete, the communication information is forwarded to a receiving party, or if the communication information is determined to be incomplete, communication fault information is sent to the indoor unit, so that the indoor unit can perform fault prompt;

one of the indoor unit and the outdoor unit of the air conditioner serves as the sender, and the other serves as the receiver.

10. The method of controlling communication between indoor and outdoor units of an air conditioner according to claim 9, further comprising;

acquiring a voltage detection signal of a power supply;

and judging whether a communication fault exists on a connecting line of the transfer device according to the voltage detection signal.

Technical Field

The invention relates to the technical field of air conditioners, in particular to an air conditioner, a transfer device and a method for controlling communication between an indoor unit and an outdoor unit of the air conditioner.

Background

For the unit air conditioner, the standard internal and external machine connecting lines are generally 3 to 5 meters, the internal machine generally uses electric heating to assist in heating, and the internal and external machines generally use current loop communication, however, under the condition that the distance between the internal machine and the external machine is far, a long connecting line needs to be used, after a certain distance is reached, the transmission loss of an indoor power supply and an outdoor power supply is large, communication is unstable or even communication cannot be realized, and data signals are lost.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, a first object of the present invention is to provide an air conditioner, which can avoid continuous attenuation of communication information even when the distance between the indoor unit and the outdoor unit is relatively long, ensure effective and reliable transmission and reception of communication information, and reduce the probability of data signal loss.

The second objective of the present invention is to provide a transfer device.

A third object of the present invention is to provide a method for controlling communication between indoor and outdoor units of an air conditioner.

In order to achieve the above object, an air conditioner according to an embodiment of a first aspect of the present invention includes: the indoor unit comprises an indoor controller and an indoor current loop communication circuit, and the indoor current loop communication circuit is connected with the indoor controller; the outdoor unit comprises an outdoor controller and an outdoor current loop communication circuit, and the outdoor current loop communication circuit is connected with the outdoor controller; and the transfer device is respectively connected with the indoor current loop communication circuit and the outdoor current loop communication circuit and is used for transferring communication information between the indoor controller and the outdoor controller.

According to the air conditioner provided by the embodiment of the invention, the transfer device is additionally arranged on the current loop communication line of the indoor unit and the outdoor unit, and the transfer device can be used for retransmitting the communication information received between the indoor unit and the outdoor unit, so that the continuous attenuation of the communication information is avoided, the communication distance which is twice as long as the original communication distance can be achieved, the current loop communication distance is increased, the reliable stability of the communication information transmission of the indoor unit and the outdoor unit is improved, and the air conditioner is suitable for the condition that the distance between the indoor unit and the outdoor unit is longer.

In some embodiments, the relay device includes: a housing; a first electrical connector disposed within the housing connected to the indoor current loop communication circuit; a second electrical connection disposed within the housing connected to the outdoor current loop communication circuit; the control unit is connected with the first electric connecting piece and the second electric connecting piece respectively and used for forwarding the communication information.

In some embodiments, the control unit is specifically configured to, when forwarding the communication information, receive communication information of a sender, and after confirming that the communication information is complete, forward the communication information to a receiver, or, when confirming that the communication information is incomplete, send communication failure information to the indoor controller to control the indoor unit to perform failure prompt; wherein one of the indoor controller and the outdoor controller serves as the sender and the other serves as the receiver.

In some embodiments, the transfer device further includes: the switching power supply is connected with the first electric connecting piece or the second electric connecting piece and is used for converting power supply voltage in the current loop communication circuit into required voltage to supply power to the control unit; the voltage detection unit is arranged in the shell and used for detecting a voltage signal of the switching power supply; the control unit is further connected with the voltage detection unit and the switching power supply and used for judging whether a communication fault exists on a connecting line of the transfer device according to the voltage signal. Therefore, communication faults caused by long communication distance can be locked quickly in time, and the specification of the cable can be adjusted conveniently in time.

In order to achieve the above object, a relay device according to an embodiment of a second aspect of the present invention is a relay device for current loop communication, the relay device including: a housing; a first electrical connector disposed within the housing; a second electrical connector disposed within the housing; and the control unit is respectively connected with the first electric connecting piece and the second electric connecting piece and is used for forwarding communication information of current loop communication between the sender and the receiver.

According to the transfer device provided by the embodiment of the invention, the first electric connecting piece and the second electric connecting piece can be connected with the current loop communication circuit of the receiving party, and the control unit is used for forwarding the communication information between the receiving party and the sending party, so that the communication distance which is twice as long as the original communication distance can be realized, the continuous attenuation of the communication information can be avoided for the current loop communication, the transfer device is suitable for the long-distance current loop communication, and the reliability and the stability of the long-distance communication information can be improved.

In some embodiments, the control unit is specifically configured to, when forwarding the communication information, receive the communication information of the sender, and after confirming that the communication information is complete, forward the communication information to the receiver, or when confirming that the communication information is incomplete, send communication failure information to perform failure notification.

In some embodiments, the transfer device further includes: the switching power supply and the first electric connecting piece or the second electric connecting piece are used for converting power supply voltage in the current loop communication circuit into required voltage to supply power to the control unit; the voltage detection unit is arranged in the shell and used for detecting and detecting a voltage signal of the switching power supply; the control unit is also connected with the voltage detection unit and the switching power supply and used for judging whether a communication fault exists on the connection line of the transfer device according to the voltage signal. Therefore, communication faults caused by long communication distance can be locked quickly, and the specification of the cable can be adjusted in time.

In some embodiments, the first electrical connector further comprises a first ground terminal and the second electrical connector further comprises a second ground terminal.

In order to achieve the above object, a method for controlling communication between an indoor unit and an outdoor unit of an air conditioner according to a third embodiment of the present invention is a relay device for forwarding communication information between the indoor unit and the outdoor unit, where the method includes; receiving communication information of a sender; judging the integrity of the communication information; if the communication information is determined to be complete, the communication information is forwarded to a receiving party, or if the communication information is determined to be incomplete, communication fault information is sent to the indoor unit, so that the indoor unit can perform fault prompt; one of the indoor unit and the outdoor unit of the air conditioner serves as the sender, and the other serves as the receiver.

According to the method for controlling the communication between the indoor unit and the outdoor unit of the air conditioner, the communication information between the indoor unit and the outdoor unit can be forwarded based on the transfer device, so that the continuous attenuation of the communication information can be avoided, the probability of data signal loss is reduced, the communication of a current loop between the indoor unit and the outdoor unit of the air conditioner in a longer distance is facilitated, and the communication stability is improved.

In some embodiments, the method further comprises; acquiring a voltage detection signal of a power supply; and judging whether a communication fault exists on a connecting line of the transfer device according to the voltage detection signal. Therefore, whether the voltage is normal or not can be fed back in time, and communication faults caused by long communication distance can be locked quickly, so that the specification of the cable can be adjusted in time.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic diagram of current loop communication between an indoor unit and an outdoor unit in the related art;

FIG. 2 is a schematic diagram of a current loop circuit in the related art;

fig. 3 is a block diagram of an air conditioner according to an embodiment of the present invention;

fig. 4 is a schematic view of connection of an indoor unit and an outdoor unit according to an embodiment of the present invention;

fig. 5 is a schematic view illustrating connection of an indoor unit and an outdoor unit according to another embodiment of the present invention;

fig. 6 is a block diagram of a relay device according to an embodiment of the present invention;

fig. 7 is a block diagram of a relay apparatus according to another embodiment of the present invention;

fig. 8 is a flowchart of a method of controlling communication between indoor and outdoor units of an air conditioner according to an embodiment of the present invention.

Detailed Description

Embodiments of the present invention will be described in detail below, the embodiments described with reference to the drawings being illustrative, and the embodiments of the present invention will be described in detail below.

The air conditioner performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve, and an evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

The compressor compresses a refrigerant gas in a high-temperature and high-pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

The expansion valve expands the liquid-phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a low-pressure liquid-phase refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a cooling effect by heat-exchanging with a material to be cooled using latent heat of evaporation of a refrigerant. The air conditioner can adjust the temperature of the indoor space throughout the cycle.

The outdoor unit of the air conditioner refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

The indoor heat exchanger and the outdoor heat exchanger serve as a condenser or an evaporator. When the indoor heat exchanger is used as a condenser, the air conditioner is used as a heater in a heating mode, and when the indoor heat exchanger is used as an evaporator, the air conditioner is used as a cooler in a cooling mode.

In an embodiment, a connection structure of an indoor unit and an outdoor unit of a single air conditioner is shown in fig. 1, and between the indoor unit and the outdoor unit, in addition to two copper pipes for flowing a refrigerant, a four-core interconnection line is further provided to connect electric devices of the indoor unit and the outdoor unit, and to transmit a power supply and a communication signal, wherein in the four-core interconnection line, one core is connected to a ground line, two cores are connected to a power supply line for transmitting a 220V operating voltage, and one core is connected to a communication line. The L/N power supply transmitted by the two-core power line supplies power to the indoor and outdoor electric control boards and also supplies power to the electric heating of the indoor unit or the compressor of the outdoor unit. That is, the communication line can be packaged into an integral electric wire as a live wire, a zero line and a ground wire, and a separate communication line is not required, so that the operation difficulty in the installation and debugging process of the whole machine is reduced.

The indoor and outdoor units of the air conditioner can adopt current loop Communication, because the distance between the indoor and outdoor units is far, if the SCI (Serial Communication Interface) of two chips is directly connected by using a wire, an electromagnetic interference signal can be introduced from the wire, and because the two wires are inevitably closely parallel to the N and L lines, an approach can be provided for introducing some interference such as power frequency 50Hz noise, therefore, the influence of the electromagnetic interference on the Communication is eliminated by adopting the strong current Communication of current loop optical coupling isolation, and meanwhile, the mains supply is adopted to directly step down and rectify the current loop to provide a power supply, so that a power frequency transformer and a rectification filter element which have high relative cost can be omitted. As shown in fig. 2, a schematic diagram of a typical current loop communication circuit is shown, the current loop communication is realized by three wires of a zero wire N, a live wire L and a communication wire SI, and includes two parts of communication circuits of an indoor machine side and an outdoor machine side, and an L/N power supply used is an ac power supply for the whole machine. As shown in fig. 2, a transmitting terminal TXD of the control IC1 of the indoor controller is connected to a receiving terminal RXD of the control IC2 of the outdoor controller through a current loop, and the receiving terminal RXD of the control IC1 is connected to a transmitting terminal TXD of the control IC2 through a current loop.

The L/N line used for the current loop communication work of the indoor unit and the outdoor unit is the L/N line in the power line, if the power socket is connected with the indoor unit and the power supply, the indoor unit supplies power to the outdoor unit, and the power of the whole outdoor unit is transmitted on the power line in the four-core integrated line, so that the power is very high; if the power socket is connected with the outdoor unit and the power supply, even if the indoor unit is a small machine, although the power of the indoor unit is not large, the electric heater is mostly arranged in the air conditioner to improve the heating effect, the electric heating power is mostly kilowatt, even larger, so that the electric power of the indoor unit is also large, and the transmission power on the power line in the on-line is also large no matter the indoor unit supplies power or the outdoor unit supplies power. Therefore, in any case, there is a possibility that the transmission power of the connection line is large, and at this time, the communication signal transmitted through the communication line is susceptible to interference, and the transmission distance becomes long, and particularly when it exceeds ten meters, the loss becomes large, the voltage is reduced, the degree of interference of the communication signal becomes large, and the phenomenon of signal loss increases until normal communication is impossible.

In order to solve the above problems, embodiments of the present invention provide an air conditioner, which can implement longer distance communication of a current loop without changing the original on-line specification and the original electric control scheme of an indoor unit and an outdoor unit, reduce the loss of communication signals between the indoor unit and the outdoor unit, and improve the communication stability.

An air conditioner according to an embodiment of the present invention will be described with reference to fig. 3 to 5.

Fig. 3 is a block diagram of an air conditioner according to an embodiment of the present invention, and as shown in fig. 3, the air conditioner 1 includes an indoor unit 11, an outdoor unit 12, and a relay unit 13.

The indoor unit 11 includes an indoor controller 111 and an indoor current loop communication circuit 112, and the indoor current loop communication circuit 112 is connected to the indoor controller 111. The indoor controller 111 is used to control the electric devices of the indoor unit 11, and can communicate with the outdoor unit 12 through the indoor current loop communication circuit 112. The indoor current loop communication circuit 112 may adopt a current loop communication circuit on the indoor unit side in current loop communication in the current air conditioner as shown in fig. 2.

The outdoor unit 12 includes an outdoor controller 121 and an outdoor current loop communication circuit 122, the outdoor current loop communication circuit 122 is connected to the outdoor controller 121, and the outdoor controller 121 is used to control electrical devices of the outdoor unit 12 and can communicate with the indoor unit 11 through the outdoor current loop communication circuit 122. The outdoor current loop communication circuit 122 may employ a current loop communication circuit on the outdoor side in current loop communication in the current conditioner as shown in fig. 2.

The special purpose device 13 is connected to the indoor current loop circuit 112 and the outdoor current loop communication circuit 122, respectively, and is configured to forward communication information between the indoor controller 111 and the outdoor controller 121.

That is, as shown in fig. 4, the relay device 13 is added to the current loop circuit connection line between the indoor unit 11 and the outdoor unit 12, and the relay device 13 may be disposed at a suitable position away from the center between the indoor unit 11 and the outdoor unit 12. The relay device 13 functions as a relay, for example, when the communication information sent by the indoor unit 11 is received and the communication information is valid, the communication information is forwarded to the outdoor unit 12, and when the communication information of the outdoor unit 12 is received and the communication information is valid, the communication information is forwarded to the indoor unit 11. The relay by the relay 13 in the current loop communication can prevent the communication information from being attenuated continuously even if there is voltage loss in the indoor unit 11 transmitting the information to the relay 13 and the information is retransmitted by the relay 13.

According to the air conditioner 1 of the embodiment of the present invention, the relay device 13 is added to the current loop communication line between the indoor unit 11 and the outdoor unit 12, and the relay device 13 can retransmit the communication information received between the indoor unit 11 and the outdoor unit 12, so as to avoid continuous attenuation of the communication information, achieve a communication distance equivalent to twice of the original communication distance, increase the current loop communication distance, and improve the reliability and stability of communication information transmission between the indoor unit and the outdoor unit.

In the embodiment, as shown in fig. 5, the relay device 13 includes a housing 131, a first connector 132, a second electrical connector 133, and a control unit 134.

Wherein, the first electrical connector 132 is disposed in the housing 131 and connected to the indoor current loop communication circuit 112. A second electrical connection 133 is disposed within the housing 131 for connection to the outdoor current loop communication circuit 122. The control unit 134 is connected to the first electrical connector 132 and the second electrical connector 133, respectively, for forwarding communication information between the indoor unit 11 and the outdoor unit 12.

In some embodiments, the housing 131 may be a closed metal box that can be fixed in place between the indoor and outdoor units. The first electrical connector 132 and the second electrical connector 133 may adopt terminal blocks, as shown in fig. 5, the first electrical connector 132 may include a first live connection terminal N1, a first neutral connection terminal L1 and a first communication terminal SI1, and the first live connection terminal N1, the first neutral connection terminal L1 and the first communication terminal SI1 are respectively connected to the indoor current loop communication circuit 112; the second electrical connection 133 may also be connected by terminals to correspond to the outdoor current loop communication circuit 122. Of course, the electrical connector may also be provided with a ground terminal for grounding the wire.

The control unit 134 is connected to the first electrical connector 132 and the second electrical connector 133, and the indoor current loop communication circuit 112 and the outdoor current loop communication circuit 122 are connected to form a complete current loop through the relay 13. When the on-line of the air conditioner is connected to the relay device 13, the commercial power can be converted into a voltage required by the control unit 134, for example, a 24V voltage, by the switching power supply, so as to supply power to the control unit 134. The control unit 134 detects the communication signal in the current loop in a circulating manner, specifically, receives the communication information of the sender, and forwards the communication information to the receiver after confirming that the communication information is complete, or sends communication fault information to the indoor controller to control the indoor unit to perform fault prompt when confirming that the communication information is incomplete; among them, one of the indoor controller and the outdoor controller serves as a sender and the other serves as a receiver. Therefore, the forwarding of the communication information between the indoor unit and the outdoor unit is realized, the continuous attenuation of the communication information is avoided, the reliability and the stability of the information are improved, and the normal communication of the air conditioner is ensured.

For example, after receiving the information sent by the indoor unit 11 and confirming the integrity of the information, the control unit 134 forwards the information to the outdoor unit 12; when the control unit 134 receives the information sent by the outdoor unit 12, it confirms the integrity of the information and then forwards the information to the indoor unit 11. If the monitored information is incomplete, for example, missing, the control unit 134 sends failure information to the indoor unit 11, and the indoor unit 11 reports the communication failure. The control unit 134 may determine the integrity of the information according to the timing and voltage amplitude of the received communication information, for example, if the rising edge or the falling edge of the pulse timing is missing or the voltage is reduced, the information is considered to be incomplete.

Further, as shown in fig. 5, the relay device 13 further includes a voltage detection unit 135, a switching power supply 136, the switching power supply 136 is connected to the first electrical connector 132 or the second electrical connector 133, and is used for converting the power voltage in the current loop communication circuit into a required voltage to supply power to the control unit 134, the voltage detection unit 135 is disposed in the housing 131 and is used for detecting a voltage signal of the switching power supply 136, that is, the power voltage input to the relay device 13; the control unit 134 is also connected to the voltage detection unit 135 and the switching power supply 136, and is configured to determine whether there is a communication failure on the connection line of the relay device 13 according to the voltage signal. Therefore, whether the voltage is normal or not can be fed back in time, and communication faults caused by long communication distance can be locked quickly, so that the specification of the cable can be adjusted in time.

The embodiment of the second aspect of the present invention further provides a relay device, where the relay device may be used for current loop communication. A relay device according to an embodiment of the present invention is described below with reference to the drawings.

Fig. 6 is a block diagram of a relay device according to an embodiment of the present invention, and as shown in fig. 6, the relay device 13 includes a housing 131, a first electrical connector 132, a second electrical connector 133, and a control unit 134.

Wherein, the first electrical connector 132 is disposed in the housing 131, and the first electrical connector 132 can be connected to a corresponding current loop communication circuit, such as an indoor current loop communication circuit, through a terminal, such as a copper bar terminal; a second electrical connector 133 is arranged in the housing 131, the second electrical connector 133 can also be connected with a corresponding current loop communication circuit through a terminal, of course, the first electrical connector 132 further comprises a first ground terminal, and the second electrical connector 133 further comprises a second ground terminal for grounding.

When mounted to the air conditioner, the first electrical connector 132 is connected to the indoor current loop communication circuit correspondingly, and the second electrical connector 133 is connected to the outdoor current loop communication circuit correspondingly. The control unit 134 is connected to the first electrical connector 132 and the second electrical connector 133 respectively, and is configured to forward communication information between the sender and the receiver to form a complete current loop communication.

According to the relay device 13 of the embodiment of the present invention, the first electrical connector 132 and the second electrical connector 133 can be connected to the current loop communication circuit of the receiving party, and the control unit 134 can forward the communication information between the receiving party and the sending party, so that the communication distance equivalent to twice of the original communication distance can be achieved.

Specifically, the control unit 134 is specifically configured to, when forwarding the communication information, receive the communication information of the sender, and after confirming that the communication information is complete, forward the communication information to the receiver, or, when confirming that the communication information is incomplete, send communication failure information for failure notification.

As shown in fig. 7, the relay device 13 further includes a voltage detection unit 135 and a switching power supply 136, the switching power supply 136 and the first electrical connector 132 or the second electrical connector 133 are used for converting the power supply voltage in the current loop communication circuit into a required voltage to supply power to the control unit; a voltage detection unit 135 is disposed in the housing 131, and is configured to detect a voltage signal of the switching power supply 136, that is, detect a power supply voltage of the input relay device 13; the control unit 134 is further connected to the voltage detection unit 135 and the switching power supply 136, and is configured to determine whether there is a communication fault on the connection line of the relay device 13 according to the voltage signal, so as to quickly lock the communication fault caused by an excessively long communication distance.

The method for controlling communication between the indoor unit and the outdoor unit of the air conditioner according to the third aspect of the present invention is described below, and the method can be used for a relay device for relaying communication information between the indoor unit and the outdoor unit.

Fig. 8 is a flowchart of a method of controlling communication between indoor and outdoor units of an air conditioner according to an embodiment of the present invention, the method including;

s1, the communication information of the sender is received.

And S2, judging the integrity of the communication information. If the communication information is determined to be complete, the process proceeds to step S3, otherwise, the communication information is determined to be incomplete, and the process proceeds to step S4.

S3, forwarding the communication to the receiving party.

And S4, sending communication fault information to the indoor unit so as to prompt the indoor unit to have a fault.

One of the indoor unit and the outdoor unit of the air conditioner serves as a transmitting side, and the other serves as a receiving side.

For example, after the relay device receives the information sent by the indoor unit and confirms the integrity of the information, the information is forwarded to the outdoor unit; when the control transfer device receives the information sent by the outdoor unit and confirms the integrity of the information, the information is transferred to the indoor unit. If the monitored information is incomplete, for example, missing occurs, the transfer device sends fault information to the indoor unit, and the indoor unit reports communication faults. The relay device may determine the integrity of the information according to the timing and the voltage amplitude of the received communication information, for example, if a rising edge or a falling edge in the pulse timing is missing or the voltage is reduced, the information is considered to be incomplete.

According to the method for controlling the communication between the indoor unit and the outdoor unit of the air conditioner, the communication information between the indoor unit and the outdoor unit can be forwarded based on the transfer device, so that the continuous attenuation of the communication information can be avoided, the probability of data signal loss is reduced, the communication of a current loop between the indoor unit and the outdoor unit of the air conditioner in a longer distance is facilitated, and the communication stability is improved.

Further, the method for controlling communication between the indoor unit and the outdoor unit of the air conditioner in the embodiment of the present invention further includes: acquiring a voltage detection signal of a power supply; and judging whether a communication fault exists on a connecting line of the transfer device according to the voltage detection signal. Therefore, whether the voltage is normal or not can be fed back in time, and communication faults caused by long communication distance can be locked quickly, so that the specification of the cable can be adjusted in time.

In summary, under the condition that the original on-line specification and the original electric control scheme of the internal and external units are not changed, the double communication distance can be realized by adding the transfer device, the continuous attenuation of communication information is avoided, the probability of communication data signal loss is reduced, and in addition, the communication fault caused by the overlong communication distance can be quickly locked.

It should be noted that in the description of the present specification, reference to the description of the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.