Patent Publication Number: US-10317106-B2

Title: Air conditioner

Description:
TECHNICAL FIELD 
     The present invention relates to an air conditioner which controls a temperature or humidity of a dwelling space or the like, and particularly to a separation type air conditioner configured of an outdoor unit and an indoor unit. 
     BACKGROUND ART 
     In such a separation type air conditioner, in order to allow the entire air conditioner to perform an optimal operation, it is necessary to transmit information by performing two-way communication between a control device of the indoor unit and a control device of an outdoor unit. For example, commands of an operation request, a change in set temperature, a timer, a change in operation mode, or a stop request, which are input by a user via a remote controller, an indoor temperature output from a temperature detection circuit or the like, an ON/OFF command of a refrigerant compressor of the outdoor unit, and the like are sent from the control device of the indoor unit to the control device of the outdoor unit. 
     In addition, a rotating speed of a refrigerant compressor of the outdoor unit, failure information of the outdoor unit, outdoor temperature information, and the like are sent from the control device of the outdoor unit to the control device of the indoor unit. In addition, each of the control devices is controlled to be integrally operated by exchanging control information signals, such as a signal about an operation condition or a set temperature. 
     Such an air conditioner is suggested in Japanese laid-open No. 2005-61676 (PTL 1) or the like, but is also suggested in many other PTLs or the like. However, as the above-described method of transmitting the control information signal, a method of transmitting a signal pulse which is a transmission signal at a predetermined frequency by connecting the control devices of the outdoor unit and the indoor unit to each other by a dedicated signal line, is known. In addition to this, a method of transmitting information by using an AC current of a power line which supplies power to the control devices of the outdoor unit and the indoor unit, is also known. 
     In general, as communication means of each of the control devices of the outdoor unit and the indoor unit of the air conditioner, at least two communication means having different communication speeds are mainly used, and in the related art, as a switching method of the communication speed, switching is performed by using a manual changeover switch. For example, the manual changeover switch is provided in the control device of the outdoor unit or the control device of the indoor unit, or in the control devices of the outdoor unit and the indoor unit, and the communication means is selected by switching each of the manual changeover switches in accordance with a communication speed selected by an installation worker of the air conditioner. 
     CITATION LIST 
     Patent Literature 
     PTL 1: Japanese laid-open No. 2005-61676 
     SUMMARY OF INVENTION 
     Technical Problem 
     Therefore, as the communication means between the control devices of the outdoor unit and the indoor unit of the air conditioner, in the air conditioner in which at least one of the two communication means having different communication speeds is used, an input of any control information signal having different communication speeds is assumed. Therefore, the control device of the indoor unit which has a microcomputer as a main configuration element decides the communication speed of the control information signal by reading set information of the manual changeover switch. 
     In this manner, it is necessary for the installation worker or the like of the air conditioner to perform switching work of the changeover switch which selects the communication speed, and there are problems that installation work is complicated, that a setting error of the changeover switch is likely to be generated, and that a normal operation of the air conditioner cannot be ensured. In addition, there is also a problem that the product prices increase since it is necessary to provide the manual changeover switch or an electric circuit related to the manual changeover switch in the control device of the outdoor unit or the indoor unit, and product competitiveness decreases. 
     An object of the present invention is to provide a new air conditioner which can recognize a communication speed of a control information signal without providing a manual changeover switch. 
     Solution to Problem 
     Characteristics of the present invention are that, in the control device of the indoor unit, a plurality of communication means having different communication speeds; communication speed recognizing means for recognizing whether or not the communication line from the outdoor unit is connected to any of the communication means, from the communication speed of the control information signal; and communication means confirmation means for confirming the communication means that performs the following communication based on the recognized communication speed, are provided. 
     Advantageous Effects of Invention 
     According to the present invention, it is also possible to recognize the communication speed of the input signal without providing the manual changeover switch. Therefore, it is possible to solve at least one or more of the problems that the installation work is complicated, that a setting error of the changeover switch is likely to be generated, and that the product prices increase. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a configuration view of an air conditioner according to a first embodiment of the present invention. 
         FIG. 2  is a configuration view of an air conditioner according to a modification example of the first embodiment. 
         FIG. 3  is a flowchart illustrating a control flow which authorizes a communication speed and is performed in the first embodiment. 
         FIG. 4  is a view describing a first authorizing method of the communication speed in the control flow illustrated in  FIG. 3 . 
         FIG. 5  is a view describing a second authorizing method of the communication speed in the control flow illustrated in  FIG. 3 . 
         FIG. 6  is a configuration view of an air conditioner according to a second embodiment of the present invention. 
         FIG. 7  is a flowchart illustrating a control flow which authorizes a communication speed and is performed in the second embodiment. 
         FIG. 8  is a configuration view of an air conditioner according to a third embodiment of the present invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, the embodiments of the present invention will be described in detail by using the drawings, but the present invention is not limited to the following embodiments, and also includes various modification examples and application examples in the range thereof in the technical concept of the present invention. 
     Example 1 
     A first embodiment of the present invention will be described in detail based on  FIGS. 1 to 5 . In  FIG. 1 , a reference number  10  is an outdoor unit which configures an air conditioner, and a refrigerant of which a temperature or a flow quantity is controlled in the outdoor unit  10  is supplied by a pipe which is not illustrated to an indoor unit  11  that also configures the air conditioner. Air of which the temperature or humidity is controlled is supplied to the inside of a room by exchanging the heat of the refrigerant and the heat of the indoor air by a blower built in the indoor unit  11 . Since a configuration or an operation of the air conditioner is well known, the description thereof will be omitted. 
     In addition, as illustrated in  FIG. 1 , a control device  12  is built in the indoor unit  11 . Since the control device  12  operates the air conditioner in a known manner and the configuration and the operation thereof are well known, the description which is not related to the example will be omitted. 
     The control device  12  has a microcomputer  13  as a main configuration element, and the microcomputer  13  includes an arithmetic operation portion which performs arithmetic operation processing according to a control program, a ROM region portion which stores the control program or a constant that is used in an arithmetic operation therein, and a RAM region portion as a work area which temporarily stores data necessary for an execution process of the program. An I/OLSI which takes in a sensor signal or a button signal and supplies a driving signal to a driving actuator, is further provided. The microcomputer  13  performs various arithmetic operation processing by the control program, but the arithmetic operation is an operation for implementing a predetermined control function, so that the processing performed by the arithmetic operation is regard as a function In the present embodiment. 
     In the control device  12 , a plurality of communication means  14   a ,  14   b , and  14   c  having different communication speeds are provided. In the embodiment, three communication means  14   a ,  14   b , and  14   c  are illustrated an example, but at least two or more communication means are provided. Furthermore, since the communication speed is determined in advance in a design stage of the air conditioner, the communication means  14   a ,  14   b , and  14   c  which correspond to the communication speed are prepared in the control device  12 . In each of the communication means  14   a ,  14   b , and  14   c , connection terminals  16   a ,  16   b , and  16   c  which are connected to the control device of the outdoor unit  10  via a communication line  15  are provided, and the communication line  15  is connected to any of the terminals  16   a ,  16   b , and  16   c . Furthermore, In the present embodiment, the communication line  15  is configured as a dedicated communication line dedicated for communication. 
     Here, In the present embodiment, since a manual changeover switch of the related art is not provided, set information is not input to the control device  12  on the indoor unit  11  side by the manual changeover switch. Therefore, the communication speed of the control information signal communicated by the communication line  15  is not known in the control device  12 . 
     By not providing the manual changeover switch, it is possible to solve at least one or more of the problems that the installation work is complicated, that a setting error of the changeover switch is likely to be generated, and that the product prices increase, which are described in “Technical Problem”. However, since the communication speed of the control information signal is not known in the control device  12 , it is necessary to determine the communication speed of the control information signal. The example has characteristics in which the communication speed is recognized by the control device  12 , and the recognizing method will be described based on  FIGS. 3 to 5 . 
     Each of the communication means  14   a ,  14   b , and  14   c  is connected to a common output port  17   a  of the microcomputer  13  and a common input port  17   b  through a bus line. Therefore, the control information signal having a certain communication speed is input to the input port  17   b , and a verification response signal which confirms the communication means  14   a ,  14   b , and  14   c  is output from the output port  17   a . When the communication means is confirmed, the following communication is performed by the confirmed communication means. 
     Furthermore, as illustrated in  FIG. 2 , it is possible to connect the communication means  14   a ,  14   b , and  14   c  to each of the corresponding output ports  17   a ,  17   c , and  17   d . However, as illustrated In the present embodiment illustrated in  FIG. 1 , it is possible to save the number of input and output ports of the microcomputer  13  by making the input and output ports  17   a  and  17   b  common, there is an effect that insufficiency of the ports of the microcomputer  13  can be solved. 
     A communication speed recognizing function portion  18  is constructed in the microcomputer  13 , the control information signal having a certain communication speed is input from the input port  17   b  to the communication speed recognizing function portion  18 . The communication speed recognizing function portion  18  has a function of recognizing whether or not the communication line  15  is connected to any of the connection terminals  16   a ,  16   b , and  16   c  of each of the communication means  14   a ,  14   b , and  14   c , from the communication speed. The communication speed recognizing function portion  18  recognizes the communication speed of the control information signal by a control flow illustrated in  FIG. 3 . Hereinafter, the operation of the control flow will be described based on  FIG. 3 . 
     In  FIG. 3 , the control flow is performed at a start-up timing which corresponds to power activation, or is performed when reaching a predetermined start-up timing after the power activation. In the present embodiment, the flowchart of  FIG. 3  is initiated in accordance with the start-up timing by the power activation. 
     &lt;&lt;Step S 10 &gt;&gt; 
     In step S 10 , a reading timing which corresponds to a first communication speed which is the highest among those of the communication means  14   a ,  14   b , and  14   c  is set, and a standby state is achieved. The setting of the plurality of communication speeds is determined in advance in a design stage of the air conditioner, and the communication speed is stored in the ROM region portion of the microcomputer  13 . In the present embodiment, three communication speeds are set, and a relationship of first communication speed&gt;second communication speed&gt;third communication speed is given. In addition, when the communication speed which is in a standby state first is set to be the highest, there is an effect that the processing of the communication speed recognition is finished quickly. In the present embodiment, the recognition is performed in order of first communication speed=&gt;second communication speed=&gt;third communication speed. 
     &lt;&lt;Step S 11 &gt;&gt; 
     Next, in step S 11 , it is determined that the control information signal sent from the outdoor unit  10  via the communication line  15  is read at a reading timing WT 1  which corresponds to the first communication speed set in step S 10 .  FIG. 4  illustrates a case where the highest first communication speed is set and a standby state is achieved. With respect to the reading timing WT 1  set in step S 10 , a control information signal SF having a high communication speed is read at the reading timing WT 1  which corresponds to the first communication speed, and thus, the current control information signal can be recognized as the control information signal SF having a high communication speed. 
     Meanwhile, regarding a control information signal SL having a low communication speed, the information which varies in accordance with the reading timing is read, and thus, the current control information signal cannot be recognized as the control information signal SF having a high communication speed. 
     In step S 11 , the process moves to step S 12  when the control information signal is determined as the control information signal SF having a high communication speed, and the process moves to step S 14  when the control information signal is not determined as the control information signal SF having a high communication speed. 
     &lt;&lt;Step S 12 &gt;&gt; 
     Since the control information signal is recognized as the control information signal SF having a high communication speed in step S 11 , the first communication speed is confirmed in step S 12 . Therefore, it is possible to recognize the control information signal sent from the outdoor unit  10  as the control information signal SF having a high communication speed. 
     &lt;&lt;Step S 13 &gt;&gt; 
     In step S 13 , the communication means which corresponds to the recognized first communication speed is confirmed as a regular communication means, the verification response signal is sent, and the following communication with the outdoor unit  10  is performed at the first communication speed. When the sending-out of the verification response signal is finished, the process proceeds to end, and the control flow is finished. 
     Meanwhile, the process moves to step S 14  when the current control information signal is not recognized as the control information signal SF having a high communication speed in step S 11 . 
     &lt;&lt;Step S 14 &gt;&gt; 
     When the current control information signal is not recognized as the control information signal having a high communication speed in step S 11 , in step S 14 , the reading timing which corresponds to the second communication speed which is lower than the current first communication speed is set and a standby state is achieved. 
     &lt;&lt;Step S 15 &gt;&gt; 
     Next, in step S 15 , it is determined whether or not the control information signal sent from the outdoor unit  10  via the communication line  15  is read at a reading timing WT 2  which corresponds to the second communication speed set in step S 14 .  FIG. 5  illustrates a case where the communication speed is set to be low and a standby state is achieved. With respect to the reading timing WT 2  set in step S 14 , the control information signal SL having a low communication speed is read at the reading timing WT 2  which corresponds to the second communication speed, and thus, the communication speed of the current control information signal can be recognized as the control information signal SL of the second communication speed. 
     On the contrary, in the control information signal SF having the first communication speed which is a high communication speed, or the control information signal having the third communication speed which is further lower than that at the reading timing set in step S 14 , the information which varies in accordance with the reading timing is read, and thus, the current control information signal is not recognized as the control information signal having the second communication signal. 
     In step S 15 , the process moves to step S 16  when it is determined that the control information signal has a communication speed of the second communication speed, and the process moves to step S 18  when it is determined that the control information signal does not have the second communication speed. 
     &lt;&lt;Step S 16 &gt;&gt; 
     In step S 15 , the communication speed is recognized as the second communication speed of the control information signal SL, and thus, in step S 16 , the communication speed is confirmed. Therefore, it is possible to recognize the control information signal sent from the outdoor unit  10  as the control information signal SL having the second communication speed. 
     &lt;&lt;Step S 17 &gt;&gt; 
     In step S 17 , the communication means which corresponds to the recognized communication speed is confirmed as a regular communication means, the verification response signal is sent, and the following communication with the outdoor unit  10  is performed at the communication speed. When the sending-out of the verification response signal is finished, the process proceeds to end, and the control flow is finished. 
     Meanwhile, the process moves to step S 18  when the current control information signal is not recognized as the control information signal having the second communication speed in step S 15 . 
     &lt;&lt;Step S 18 &gt;&gt; 
     When the current control information signal is not recognized as the control information signal having the second communication speed in step S 15 , in step S 18 , the reading timing which corresponds to the third communication speed that is lower than the current second communication speed is set and a standby state is achieved. 
     &lt;&lt;Step S 19 &gt;&gt; 
     Next, in step S 19 , it is determined whether or not the control information signal sent from the outdoor unit  10  via the communication line  15  is read at the reading timing which corresponds to the third communication speed set in step S 18 . The determination is performed by a method which is the same as the method illustrated in  FIG. 4 or 5 . Since a reading timing WT 3  (not illustrated) is set in step S 18 , the control information signal communicated at the third communication speed is read at the reading timing WT 3 . Therefore, the communication speed of the current control information signal can be recognized as the control information signal of the third communication speed. On the contrary, in the control information signals having the first communication speed and the second communication speed which are higher than the third communication speed, the information which varies in accordance with the reading timing is read, and thus, the current control information signal is not recognized as the control information signal of the third communication speed. 
     In step S 19 , the process moves to step S 20  when it is determined that the control information signal has the communication speed of the third communication speed, and the process moves to step S 22  when it is determined that the control information signal does not have the third communication speed. 
     &lt;&lt;Step S 20 &gt;&gt; 
     In step S 19 , the control information signal of which the communication speed is the third communication speed is recognized, and thus, the communication speed is confirmed in step S 20 . Therefore, it is possible to recognize the control information signal sent from the outdoor unit  10  as the control information signal having the third communication speed. 
     &lt;&lt;Step S 21 &gt;&gt; 
     In step S 21 , the communication means which corresponds to the recognized communication speed is confirmed as a regular communication means, the verification response signal is sent, and the following communication with the outdoor unit  10  is performed at the communication speed. When the sending-out of the verification response signal is finished, process proceeds to end, and the control flow is finished. 
     Meanwhile, the process moves to step S 22  when the current control information signal is not recognized as the control information signal having the third communication speed in step S 19 . In other words, when moving to step S 22 , the current control information sent from the communication line  15  is considered as information of a mistaken communication speed. 
     &lt;&lt;Step S 22 &gt;&gt; 
     In step S 22 , it is determined whether or not a flow of passing through step S 11 =&gt;step S 15 =&gt;step S 19 =&gt;step S 22  is repeated for a predetermined number of times. The process moves to step S 23  when the repetition is performed for the predetermined number of times, and the process returns to step S 10  in a case where the predetermined number of times of repetition is not achieved, so that the same operation is repeated. The predetermined number of times is arbitrary, but when the predetermined number of times increases, it is possible to improve possibility of recognition of the communication speed even when the communication state is not excellent. Furthermore, in a case where it is not necessary to perform repetition only for the predetermined number of times, the process may move to step S 23  by the first determination in step S 19  as illustrated by a broken line. 
     &lt;&lt;Step S 23 &gt;&gt; 
     In step S 11 , since the control information signal sent from the outdoor unit  10  is not read even though the repetition for the predetermined number of times is performed, it is determined that the communication is abnormal, and the alarm is generated. After this, the process proceeds to end and the control flow is finished. 
     Here, In the present embodiment, three types of communication speeds is described as an example, but in a case where there are more than three types of communication speeds, in control step S 15  to step S 18 , control steps S 14  to S 17  of recognizing other communication speeds may be provided in accordance with the type of the communication speed. 
     According to the present example, by providing the plurality of communication means having different communication speeds in the control device of the indoor unit; the communication speed recognizing means for recognizing whether or not the communication line from the outdoor unit is connected to any of the communication means, from the communication speed of the control information signal; and the communication means confirmation means for confirming the communication means that performs the following communication based on the recognized communication speed, it is possible to recognize the communication speed of the input signal without providing the manual changeover switch. Therefore, it is possible to solve the problems that the installation work is complicated, that a setting error of the manual changeover switch is likely to be generated, and that the product prices increase. 
     Example 2 
     Next, a second embodiment of the present invention will be described by using  FIGS. 6 and 7 . In  FIG. 6 , the control device  12  of the indoor unit  11  which performs the communication with the outdoor unit  10  includes power line communication means  20  which uses the power line, and dedicated line communication means  21  to which the dedicated communication line having a communication speed different from that of the power line communication means  20  is connected. Here, the dedicated line communication means  21  is provided with a dedicated communication circuit. Each of the communication means  20  and  21  is provided with connection terminals  22   a  and  22   b  to which the communication line  15 , which is connected to the outdoor unit  10  is connected, and the communication line  15  is connected to any of the connection terminals  22   a  and  22   b.    
     Here, the power line communication means  20  which uses the power line is provided with a signal converting portion  20   a  by a photocoupler (PHT CUP), and a strong power signal is converted to a weak power signal and is converted to a signal level handled by the microcomputer  13 . 
     Similar to  FIG. 1 , each of the communication means  20  and  21  is connected to the common output port  17   a  and the common input port  17   b  of the microcomputer  13  through the bus line. Therefore, the control information signal having a communication speed of any of the communication means  20  and  21  is input to the input port  17   b , and the verification response signal which confirms any of the communication means  20  and  21  is output from the output port. When the communication means is confirmed, the following communication is performed by the confirmed communication means. 
     In addition, the power line communication means  20  which uses the power line and the dedicated line communication means  21  which uses the dedicated circuit are connected to the common input port  17   b , and an opening and closing transistor  23  (hereinafter, will be described as a transistor  23 ) which can be ON/OFF by the control signal from an output port  17   e  is provided between the power line communication means  20  and the input port  17   b . Similarly, an opening and closing transistor  24  (hereinafter, will be described as a transistor  24 ) which can be ON/OFF by the control signal from an output port  17   f  is provided between the dedicated line communication means  21  and the input port  17   b.    
     Functions of the transistors  23  and  24  are for preventing influence of the communication signal which is not intended or assumed from the power line communication means  20  or the dedicated line communication means  21  which is not used, after the recognition of the communication speed is finished. 
     A communication speed recognizing function portion  25  is constructed in the microcomputer  13  similar to Example 1, and the control information signal having a certain communication speed is input from the input port  17   b  to the communication speed recognizing function portion  25 . The communication speed recognizing function portion  25  has a function of recognizing whether or not the communication line  15  is connected to any of the connection terminals  22   a  and  22   b  of each of the communication means  20  and  21 , from the communication speed. The communication speed recognizing function portion  25  recognizes the communication speed of the control information signal by the control flow illustrated in  FIG. 7 . Hereinafter, an operation of the control flow will be described based on  FIG. 7 . 
     In  FIG. 7 , the control flow is also performed at an start-up timing which corresponds to power activation similar to Example 1, or is performed when reaching a predetermined start-up after the power activation. In the present embodiment, the flowchart of  FIG. 7  is initiated in accordance with the start-up timing by the power activation. 
     &lt;&lt;Step S 30 &gt;&gt; 
     In step S 30 , a control signal for turning on the transistors  23  and  24  is sent from the output ports  17   e  and  17   f  of the microcomputer  13 , and according to this, the transistors  23  and  24  are turned on. Therefore, both of the power line communication means  20  which uses the power line and the dedicated line communication means  21  which uses the dedicated circuit are connected to the input port  17   b  of the microcomputer  13 . Therefore, the control information signal from the power line communication means  20  or the dedicated line communication means  21  is input. 
     &lt;&lt;Step S 31 &gt;&gt; 
     In step S 31 , it is assumed that the communication line  15  is connected to the connection terminal  22   b  included in the dedicated line communication means  21 , a standby state is achieved at the reading timing at which the communication is possible at the communication speed of the dedicated line communication means  21 . Here, the communication speed of the dedicated line communication means  21  is higher than that of the power line communication means  20  which uses the power line, and a possibility to be used is also high, and thus, there is an effect that the processing of the communication speed recognition is finished quickly. 
     &lt;&lt;Step S 32 &gt;&gt; 
     Next, in step S 32 , the process moves to step S 33  in a case where the control information signal sent from the outdoor unit  10  is read at the communication speed of the dedicated line communication means  21  set in step S 31 . Meanwhile, the process moves to step S 36  in a case where the control information signal is not read. When the control information signal of the communication speed of the dedicated line communication means  21  is input to the input port  17   b , the communication speed recognizing function portion  25  is in a standby state at the communication speed of the dedicated line communication means  21 , and thus, it is possible to read the control information signal of the communication speed of the dedicated line communication means  21  similar to Example 1. 
     Meanwhile, when the control information signal of the communication speed of the power line communication means  20  which uses the power line is input, the communication speed recognizing function portion  25  is in a standby state at the communication speed of the dedicated line communication means  21 , and thus, the control information signal of the communication speed of the power line communication means  20  is not read similar to Example 1. 
     &lt;&lt;Step S 33 &gt;&gt; 
     Since the current control information signal is recognized as the control information signal from the dedicated line communication means  21  in step S 32 , in step S 33 , the communication speed at this time is confirmed. Therefore, it is possible to recognize the control information signal sent from the outdoor unit  10  as the control information signal of the dedicated line communication means  21 . The process moves to step S 34  when the confirmation of the communication speed is finished. 
     &lt;&lt;Step S 34 &gt;&gt; 
     In step S 34 , since the current communication speed is confirmed at the communication speed of the dedicated line communication means  21 , by outputting an OFF signal from the output port  17   e  to the transistor  23  disposed between the power line communication means  20  and the input port  17   b , the transistor  23  is turned off and the connection between the power line communication means  20  and the input port  17   b  is blocked. Accordingly, it is possible to improve reliability of the communication since the communication signal which is not intended or assumed from the power line communication means  20  is not transmitted to the input port  17   b . The process moves to step S 35  when the OFF control of the transistor  23  is finished. 
     &lt;&lt;Step S 35 &gt;&gt; 
     In step S 35 , the verification response signal is sent considering the recognized dedicated line communication means as a regular communication means, and the following communication with the outdoor unit  10  is performed at the communication speed of the dedicated line communication means  21 . When the sending-out of the verification response signal is finished, the process proceeds to end, and the control flow is finished. 
     Meanwhile, when the current control information signal is not recognized as the control information signal of the dedicated line communication means  21  in step S 32 , the process moves to step S 36 . 
     &lt;&lt;Step S 36 &gt;&gt; 
     When the current control information signal is not recognized as the control information signal from the dedicated line communication means  21  in step S 32 , in step S 36 , the reading timing which corresponds to the power line communication means  20  that uses the power line is set and a standby state is achieved. 
     &lt;&lt;Step S 37 &gt;&gt; 
     Next, in step S 37 , the process moves to step S 38  in a case where the control information signal sent from the outdoor unit  10  is read at the communication speed of the power line communication means  20  set in step S 36 . Meanwhile, the process moves to step S 41  in a case where the control information signal is not read. In step S 37 , similar to Example 1, when the control information signal having the communication speed of the power line communication means  20  is input to the input port  17   b , the communication speed recognizing function portion  25  is also in a standby state at the communication speed of the power line communication means  20 , and thus, it is possible to read the control information signal of the communication speed of the power line communication means  20  similar to Example 1. On the contrary, when the control information signal of the communication speed of the dedicated line communication means  21  is input, the communication speed recognizing function portion  25  is in a standby state at the communication speed of the power line communication means  20 , and thus, similar to Example 1, the control information signal of the communication speed of the dedicated line communication means  21  is not read. 
     &lt;&lt;Step S 38 &gt;&gt; 
     Since the current control information signal is recognized as the control information signal from the power line communication means  20  in step S 37 , in step S 38 , the communication speed at this time is confirmed. Therefore, it is possible to recognize the control information signal sent from the outdoor unit  10  as the control information signal of the power line communication means  20 . The process moves to step S 39  when the confirmation of the communication speed is finished. 
     &lt;&lt;Step S 39 &gt;&gt; 
     In step S 39 , since the current communication speed is confirmed at the communication speed of the power line communication means  20 , by outputting an OFF signal from the output port  17   e  to the transistor  24  disposed between the dedicated line communication means  21  and the input port  17   b , the transistor  24  is turned off and the connection between the dedicated line communication means  21  and the input port  17   b  is blocked. Accordingly, it is possible to improve reliability of the communication since the communication signal which is not intended or assumed from the dedicated line communication means  21  is not transmitted to the input port  17   b . The process moves to step S 40  when the OFF control of the transistor  24  is finished. 
     &lt;&lt;Step S 40 &gt;&gt; 
     In step S 40 , since the verification response signal is sent considering the recognized power line communication means as regulated communication means, the following communication with the outdoor unit  10  is performed at the communication speed of the power line communication means  20 . When the sending-out of the verification response signal is finished, the process proceeds to end, and the control flow is finished. 
     Meanwhile, the process moves to step S 41  when the current control information signal is not recognized as the control information signal of the power line communication means  20  in step S 37 . In other words, when the process moves to step S 41 , the current control information sent from the communication line  15  is considered as information of a &lt;&lt;Step S 41 &gt;&gt; 
     In step S 41 , it is determined whether or not the flow of passing through step S 32 =&gt;step S 37 =&gt;step S 41  is repeated for a predetermined regulated number of times. The process moves to step S 42  when the repetition is performed for a predetermined number of times, and the process returns to step S 31  in a case where the predetermined number of times of repetition is not achieved similar to Example 1, so that the same operation is repeated. When the number of times of repetition is large, it is possible to improve possibility of recognition of the communication speed even when the communication state is not excellent. Furthermore, in a case where it is not necessary to perform repetition only for the predetermined number of times, the process may move to step S 42  by the first determination in step S 19  as illustrated by a broken line. 
     &lt;&lt;Step S 42 &gt;&gt; 
     In step S 42 , since the control information signal sent from the outdoor unit  10  is not read even though the repetition for the predetermined number of times is performed, it is determined that the communication is abnormal, and the alarm is generated. After this, the process proceeds to end and the control flow is finished. 
     According to the present example, by providing the power line communication means and the dedicated line communication means which have different communication speeds in the control device of the indoor unit; the communication speed recognizing means for recognizing whether or not the communication line from the outdoor unit is connected to any of the communication means of the power line communication means and the dedicated line communication means, from the communication speed of the control information signal; and the communication means confirmation means for confirming the following communication means based on the recognized communication speed, it is possible to recognize the communication speed of the input signal without providing the manual changeover switch. Therefore, it is possible to solve the problems that the installation work is complicated, that a setting error of the changeover switch is likely to be generated, and that the product prices increase. 
     Furthermore, since the transistor for opening and closing the connection is provided between each of the communication means and the input port, the connection with the input port is blocked other than the recognized communication means. According to this, influence of the communication signal which is not intended or assumed from the communication means which is not used is prevented, after the recognition of the communication speed is finished. 
     Example 3 
     Next, a third embodiment of the present invention will be described by using  FIG. 8 , but basically, the configuration is similar to that of Example 2. In  FIG. 8 , the control device  12  of the indoor unit  11  which performs the communication with the outdoor unit  10  includes the power line communication means which uses the power line, and the dedicated line communication means  21  to which the dedicated communication line having a communication speed different from that of the power line communication means  20  is connected. Here, the dedicated line communication means  21  is provided with the dedicated communication circuit. Each of the communication means  20  and  21  is provided with the connection terminals  22   a  and  22   b  to which the communication line  15 , which is connected to the outdoor unit  10  is connected, and the communication line  15  is connected to any of the connection terminals  22   a  and  22   b.    
     The power line communication means  20  which uses the power line is provided with the signal converting portion  20   a  by the photocoupler (PHT CUP), and the strong power signal is converted to the weak power signal and is converted to a signal level handled by the microcomputer  13 . 
     Similar to  FIG. 2 , each of the communication means  20  and  21  is connected to the common input port  17   b  of the microcomputer  13  through the bus line, and the control information signal of any of the power line communication means  20  and the dedicated line communication means  21  is input to the input port  17   b.    
     Meanwhile, the output ports are individually connected to each of the communication means  20  and  21 , the power line communication means  20  is connected to the output port  17   a , the dedicated line communication means  21  is connected to an output port  17   g , and the signals which confirm the each of the communication means  20  and  21  from each of the output ports  17   a  and  17   g  are individually output. This point is different from Example 2. By separating the output ports in this manner, it is possible to reliably confirm the communication means. 
     In addition, the power line communication means  20  and the dedicated line communication means  21  are connected to the common input port  17   b , the transistor  23  which can be ON/OFF by the control signal from the output port  17   e  is provided between the power line communication means  20  which uses the power line and the input port  17   b . Meanwhile, the transistor in Example 2 is omitted between the dedicated line communication means  21  which uses the dedicated circuit and the input port  17   b . This point is also different from Example 2. In addition, the function of the transistor  23  is similar to that of Example 2. In this manner, the transistor  24  is omitted, and thus, it is possible to make the circuit configuration of the control device  11  simple, and additionally, the control flow can be simplified. Since the transistor  24  is omitted, in the flowchart illustrated in  FIG. 7 , it is possible to omit an instruction of an ON operation of the transistor  24  of step S 30  and an instruction of an OFF operation of the transistor  24  of step S 39 . Furthermore, since other configurations are similar to those of Example 2, further description is omitted. 
     As described above, the present invention includes the plurality of communication means having different communication speeds in the control device of the indoor unit; the communication speed recognizing means for recognizing whether or not the communication line from the outdoor unit is connected to any of the communication means, from the communication speed of the control information signal; and the communication means confirmation means for confirming the communication means that performs the following communication based on the recognized communication speed. 
     According to this, it is possible to recognize the communication speed of the input signal without providing the manual changeover switch. Therefore, it is possible to solve at least one or more of the problems that the installation work is complicated, that a setting error of the changeover switch is likely to be generated, and that the product prices increase. 
     Furthermore, the present invention is not limited to the above-described examples, and various modification examples are included. For example, the above-described examples are described in detail for making it easy to understand the present invention, and it is not necessary to provide all of the described configurations. In addition, it is possible to replace a part of the configuration of the example with other examples, and to add the configurations of other examples to a certain example. In addition, regarding a part of the configurations of each example, other configurations can be added, removed, and replaced. 
     REFERENCE SIGNS LIST 
     
         
         
           
               10  . . . outdoor unit, 
               11  . . . indoor unit, 
               12  . . . control device, 
               13  . . . microcomputer, 
               14   a ,  14   b ,  14   c  . . . communication means, 
               15  . . . communication line, 
               16   a ,  16   b ,  16   c  . . . connection terminal, 
               17   a ,  17   b ,  17   c ,  17   d ,  17   e ,  17   f  . . . input and output port, 
               18  . . . communication speed recognizing function portion, 
               20 ,  21  . . . communication means, 
               20   a  . . . signal converting portion, 
               22   a ,  22   b  . . . connection terminal, 
               23 ,  24  . . . transistor