Electric power supply apparatus of air condition control machine

An air condition control unit is provided with an EEPROM previously memorizing respectively different specific numbers of indoor control units and power supply means. Further provided thereto are power supply judging means for judging whether a remote controller receives the power from another indoor control unit by monitoring power source lines, and power not-supply determining means for determining the unit of its own to be a unit which does not supply the power to the remote controller when the power supply judging means judges the remote controller receives the power. In addition, provided thereto are power supply timing means for setting a power supply timing based on the specific numbers and power supply determining means for determining the unit of its own to be a unit which supplies the power to the remote controller for making the power supply means supply the power to the remote controller when the power supply judging means judges the remote controller to be in a state that no power is supplied thereto at the power supply timing by the timing means. Consequently, the indoor control units are standardized and the power can be without failure supplied to the remote controller.

TECHNICAL FIELD 
This invention relates to an electric power supply apparatus for an air 
conditioning control machine which has a controller and an air 
conditioning control unit. 
BACKGROUND ART 
Generally, as disclosed in Japanese Patent Application Laying Open Gazette 
No. 2-85634, an air conditioner has been disclosed, in which a single 
remote controller is connected to a plurality of indoor control units for 
respectively controlling a plurality of indoor units so that control 
signals such as operation signals are sent and received between the remote 
controller and each of the indoor control units to control an air 
conditioning operation. 
Between each indoor control unit and the remote controller, electric power 
is supplied from a previously designated indoor control unit to the remote 
controller. In addition, an address of each indoor control unit is set and 
data including error signals, wind direction signals and the like may be 
transmitted therebetween. 
In the above mentioned air conditioning control machine, the address of the 
indoor control unit that supplies electric power to the remote controller 
is conventionally set to 0 by the remote controller. However, power cannot 
be supplied to the remote controller by the power supply unless the power 
supply's address is set to each indoor control unit. This creates a 
communication problem wherein communication is not performed between the 
remote controller and the indoor control unit such that the address is not 
automatically set. 
One solution is for the address of the control unit that powers the remote 
controller to be previously set in hardware. This, however, requires that 
a printed circuit board be manufactured individually so that the indoor 
control units cannot be standardized. 
In view of the above mentioned problems, it is an object of the present 
invention to supply electric power to the controller in a stable manner, 
by standardizing the air conditioning control units. 
DISCLOSURE OF INVENTION 
To attain the foregoing object, in the present invention, an air 
conditioning control unit for supplying electric power is determined using 
a specific number previously set with respect to each air conditioning 
control unit. 
Specifically, as shown in FIG. 1, an electric power supply apparatus of an 
air conditioning control unit 2, according to a first embodiment of the 
invention, includes a plurality of air conditioning control units 2 
connected to a single controller 3 via wirings 52 through which control 
signals between the remote controller 3 and the air conditioning indoor 
control units 2 are sent and received to control air conditioning 
operation. 
Provided at each air conditioning control unit 2 are number memory means 
24, for previously memorizing different specific numbers corresponding to 
the respective air conditioning control units 2; power supply means 51 for 
supplying electric power; power supply judging means (or power-on means) 
21a, for detecting whether another air conditioning control unit 2 is 
powering the controller 3, which is done by monitoring the wirings 52; 
power control means (or no-power-supply means) 21b for determining to not 
supply electric power to the controller 3, which is when the power supply 
judging means (or power-on means) 21a detects that the controller 3 is 
being powered; timing means 21c, for setting a power supply time based on 
a specific number; and power supply determining means (or power activation 
means) 21d for determining to supply electric power to the controller 3, 
which is when the power supply judging means (or power-on means) 21a 
detects that the controller 3 is not being powered at the time established 
by the timing means 21c and for enabling the power supply means 51 to 
supply electric power to the controller 3. 
As in the first embodiment, a second embodiment of the present invention 
discloses an electric power supply apparatus for an air conditioning 
control machine. As shown in FIG. 2, each air conditioning control unit 2 
includes number memory means 24 for previously storing a specific number 
assigned to each of the air conditioner control units 2, and which is 
different for each air conditioning control unit 2; a power supply means 
51 for supplying electric power to the remote controller 3; a power supply 
judging means (or power-on means) 21a for detecting, through monitoring of 
the wirings 52, whether another air conditioning control unit 2 is 
supplying electric power to the controller 3; and a power control means 
(or no-power-supply means) 21b for determining not to supply electric 
power to the remote controller 3, which is when the power supply judging 
means (or power-on means) 21a detects that the remote controller 3 is 
powered. The air conditioning control unit 2 further includes timing means 
21f for setting a time for powering the remote controller 3 by the control 
units 2 based on one of a pluralality of sectional numbers that result 
from the mathematical division of the specific number stored in the number 
memory means 24; fixed power supply means 21g for enabling the power 
supply means 51 to supply electric power to the remote controller 3 at the 
time set by the timing means 21f; and power supply determining means (or 
power activation means) 21h for determining to supply electric power to 
the controller 3, which is when the fixed power supply means 21g enables 
the power supply means 51 as per all the sectional numbers obtained from 
the mathematical division of each one of the control unit's 2 preassigned 
numbers, respectively. 
In an electric power supply apparatus for an air conditioning control 
machine according to the first and second embodiments, in addition to the 
above discussed elements, the invention provides a power supply stop means 
(or power interrupting means) 21e for stopping the power supply when an 
irregularity in the power supply is detected. 
A third embodiment of the invention includes, as in the first embodiment, 
an electric power supply apparatus of an air conditioning control machine 
as shown in FIG. 3. The air conditioning control unit 2 comprises: number 
memory means 24 for previously storing a different specific number 
corresponding to each of the air conditioner control units 2; power supply 
means 51 for supplying electric power to the remote controller 3; power 
supply judging means (or power-on means) 21a for detecting, by monitoring 
of the wirings 52, whether another air conditioning control unit 2 is 
powering the controller 3; and first power control means (or no 
power-supply means) 21b for determining the air conditioning control unit 
2 is not to power the controller 3, which is when the power supply judging 
means (or power-on means) 21a detects that the controller 3 is receiveing 
electric power. In addition, the air conditioning control unit 2 further 
includes timing means 21f for setting a time of power supply based on each 
one of plural sectional numbers resulting from a mathematical division of 
the specific number corresponding to each air conditioning control unit 2; 
fixed power supply means 21g for enabling the power supply means 51 to 
supply electric power to the remote controller 3 at a time pre-set as per 
the timing means 21f; and power supply notice means 21i for sending a 
notice signal of a predetermined voltage when the fixed power supply means 
21g begins powering the controller 3. Further, the air conditioning 
control unit 2 features a second power control means (or no-power-supply 
means) 21j for determining not to supply electric power to the controller 
3, which is when a notice signal is detected from another air conditioning 
control unit when monitoring the wirings 52; power supply stop means (or 
power interrupting means) 21e for stopping the power supply of the fixed 
power supply means 21g at a time determined by the pre-set time assigned 
to a specific control unit's 2 power supply when an irregularity of the 
power source is detected by monitoring the wirings 52; and power supply 
determining means (or power activation means means) 21h for determining to 
supply electric power to the remote controller 3, which is when the fixed 
power supply means 21g brings a normal power supply for all the air 
conditioning control unit's sectional numbers. 
In the first embodiment, the power supply judging means (or power-on means) 
21a detects whether electric power is supplied to the remote controller 3 
from another air conditioning control unit 2 when a power source is turned 
ON. When the power supply judging means (or power-on means) 21a detects 
that the controller 3 is receiving power, the power control means (or 
no-power-supply means) 21b determines that the air conditioning unit shall 
not supply electric power. If the remote controller 3 is not receiving 
power, the timing means 21c sets a time for power supply based on the 
specific number previously given to each air conditioning control unit 2. 
For example, the timing means 21c sets the time of power supply by 
multiplying the specific number by 10 ms. Then, when the power supply 
judging means (or power-on means) 21a detects that the controller 3 is not 
receiving power at the pre-set time, the power supply determining means 
(or power activation means) 21d determines the air conditioning control 
unit 2 to be a unit which supplies electric power to the controller 3. 
When the power is supplied to the controller 3 from the power supply means 
51, a control signal is sent and received between each air conditioning 
control unit 2 and the controller 3. 
In the second embodiment, as in the first embodiment, the power supply 
judging means (or power-on means) 21a detects if the remote controller 3 
is receiving power from another air conditioning control unit 2 when a 
power source is turned ON. When the power supply judging means (or 
power-on means) 21a detects that the controller 3 is receiving power, the 
power control means (or no-power-supply means) 21b determines to not 
supply electric power. 
On the other hand, if the remote controller 3 is not being powered, the 
timing means 21f sets a time for power supply based on the plural 
sectional numbers obtained from the mathematical division of a 24-bit 
specific number given to each air conditioning controller 3. For example, 
the timing means 21f designates three different numbers which correspond 
to times for power supply which are obtained by multiplying the above 
mentioned 24-bit specific number by 10 ms per sectional number of 1 byte 
thereof. Then, the fixed power supply means 21g powers the remote 
controller 3 at the given times of power supply. 
When another air conditioning control unit 2 supplies electric power to the 
remote controller 3 between the times of power supply, the power control 
means (or no-power-supply means) 21b determines to not supply electric 
power. On the other hand, if electric power is normally supplied, the 
power supply determining means (or power activation means) 21h enables the 
air conditioning control unit 2 to supply electric power from the unit's 
power supply means 51 to the controller 3, and a control signal is sent 
and received between each air conditioning control unit 2 and the 
controller 3. When there is some irregularity with the power source at 
each of the power supply times, the power supply stop means (or power 
interrupting means) 21e stops the power supply. 
In the third embodiment, as well as in the second embodiment, the power 
supply judging means (or power-on means) 21a detects whether electric 
power is supplied from another air conditioning control unit 2 to the 
controller 3. When the power supply judging means (or power-on means) 21a 
detects that the controller 3 receives the power, the first power control 
means (or first no-power-supply means) 21b determines to not supply 
electric power. If the controller is not powered, the timing means 21f 
sets times of power supply based on the plural sectional numbers obtained 
by a mathematical division of the individual specific number of each air 
conditioning control unit. Then, the fixed power supply means 21g powers 
the controller 3 at the corresponding pre-set time, and the power supply 
notice means 21i sends a notice signal indicating that power has been 
supplied. 
When the power is supplied from another air conditioning control unit 2 to 
the controller between the times of power supply, the first power control 
means (or first no-power-supply means) 21b determines to not supply 
electric power. At the time when the notice signal is output from another 
air conditioning control unit 2, the second power control means (or second 
no-power-supply means) 21j determines to not supply electric power. If 
there is an irregularity with the power source at each of the power supply 
times, the power supply stop means (or power interrupting means) 21e stops 
the power supply of the fixed power supply means 21g. If there is no 
irregularity, the power supply determining means (or power activation 
means) 21h enables the particular air conditioning control unit 2 to power 
the controller 3; the power is supplied from the air conditioning control 
unit's power supply means 51 to the controller 3, and a control signal is 
sent and received between each air conditioning control unit 2 and the 
controller 3. 
The first embodiment ensures that power is supplied to the remote 
controller 3 when necessary, since a pre-set number is given to each air 
conditioning control unit 2 and will enable the supply of power at the 
appropriate time. Therefore, communication between the remote controller 3 
and the air conditioning control units 2 is steadily established. Further, 
each address of the indoor control unit 2 can be automatically set, and 
printed circuit boards of the air conditioning control units 2 can be 
standardized thus facilitating the air conditioning control unit's 
manufacture. 
The second embodiment ensures a rapid selection of the air conditioning 
control unit 2 that is to supply electric power to the remote controller 
3, since the time of power supply is determined by a mathematical division 
of the pre-assigned individual specific number into plural numbers. 
According to the third embodiment, since the power supply to the remote 
controller 3 is detected by a notice flag 21i, even when the power supply 
of the fixed power supply means 21g occurs simultaneously with that of 
another air conditioning control unit, the air conditioning control unit 
supplying power to the controller 3 can be identified based on a 
mathematical difference between the specific numbers.

BEST MODE FOR CARRYING OUT THE INVENTION 
The following is a detailed description of the preferred embodiment of the 
present invention with reference to the accompanying drawings. As shown in 
FIGS. 4 and 5, reference numeral 1 indicates an outdoor control unit for 
controlling an outdoor unit and 2 indicates an indoor control unit for 
controlling an indoor air conditioning unit. The outdoor control unit 1 is 
connected to a plurality of indoor control units 2 and a single remote 
controller 3 is connected to a plurality of (at most sixteen) indoor 
control units 2 via transmission paths 4. 
The outdoor control unit 1 has a micro-computer 11 and a transmission 
circuit 12 which is connected to the micro-computer 11. The transmission 
circuit 12 is connected to each indoor control unit 2 via the transmission 
paths 4 and communicates with the indoor control unit 2 receiving 
therefrom control signals like air conditioning load and the like. 
Further, each indoor control unit 2 has a micro-computer 21 connected with 
transmission circuits 22 and 23, and, in turn, the transmission circuit 22 
is connected to the outdoor control unit 1 via the transmission path 4, 
whereas the transmission circuit 23 is connected to the remote controller 
3 via the transmission path 4 so that control signals of the indoor 
control unit 2, such as error signals or wind direction signals are sent 
and received between the indoor control unit 2 and the remote controller 
3. 
Furthermore, the remote controller 3 has a micro-computer 31 connected to a 
transmission circuit 32, to a display 33 which displays an operation or 
the like, and to an input means 34 which inputs operation signals. The 
transmission circuit 32 is in turn connected to each indoor control unit 
2. 
In addition, a power supply circuit 5 is provided at the indoor control 
unit 2, which includes, as shown in FIG. 6, power supply means 51 having a 
power storage element to be used for control operations. The power supply 
means 51 is connected to each indoor control unit 2 and the remote 
controller 3 via two power source wirings 52. The power source wirings 52 
are connected to overcurrent detecting means 53, for detecting an 
overcurrent, and power source detecting means 54, for detecting power 
supply from the power supply means 51 to the remote controller 3. An 
EEPROM is provided at each indoor control unit 2, which includes number 
memory means 24 to store a pre-assigned number. The specific number is 
composed of 24 bits as a bit row of a set length. Different specific 
numbers are assigned to each indoor control unit at a given stage in the 
manufacturing process or when the unit is sent for shipment. 
In addition, the first embodiment's power supply apparatus features a power 
supply judging means (or power-on means) 21a, power control means (or 
no-power-supply means) 21b, timing means 21c and power supply determining 
means (or power activation means) 21d which are provided in the 
micro-computer 21 of the indoor control unit 2. The power supply judging 
means (or power-on means) 21a monitors the power source wirings 52 in such 
a manner as to receive a detection signal from the power source detecting 
means 54, and detects whether another indoor control unit 2 is supplying 
electric power to the remote controller 3. The power control means (or 
no-power-supply means) 21b determines to not supply electric power to the 
remote controller 3 when the power supply judging means (or power-on 
means) 21a detects that electric power is being supplied to the remote 
controller 3. The timing means 21c sets a time for power supply to the 
remote controller 3 based on the pre-assigned specific number, which is, 
for example, calculated by multiplying such number by 10 ms. Moreover, 
when the power supply judging means (or power-on means) 21a detects that 
no power is supplied to the remote controller 3 at the time of power 
supply set by the timing means 21c, the power supply determining means (or 
power activation means) 21d enables the power supply to the remote 
controller 3, by activating the power supply means 51. 
The power supply stop means (or power interrupting means) 21e resides in 
the micro-computer 21 of the indoor control unit 2 and is designed to 
interupt the power supply when it receives an overcurrent signal from the 
overcurrent detecting means 53, which is when it detects a connection 
error due to heteropolarity (i.e. cross polarization). 
The following is a description of a power supply operation from the indoor 
control unit 2 to the remote controller 3 for the first embodiment, and 
which is illustrated in FIG. 7. When the power source is turned ON, an 
error count N is initially set to 0. At a step ST1, a specific number of 
the indoor control unit is read out from an EEPROM 24 and a time TM for a 
power supply time is set by multiplying the specific number by 10 ms. 
Then, the routine proceeds to a step ST2 and examines whether the time of 
the timer TM has been reached. The routine is kept waiting at the step ST2 
until the time is reached. Then, the routine proceeds to a step ST3, where 
the routine determines, through a signal from the power source detecting 
means 54, whether the remote controller 3 has a set voltage; that is, 
whether it is receiving power from another control unit 2. At this point, 
if it is detected that the remote controller 3 is being powered, the unit 
is not enabled to supply electric power to the controller 3 and an 
AFFIRMATIVE flag is turned on that allows the routine to proceed to step 
ST4. 
At the step ST4, the routine determines whether the remote controller 3 has 
a set voltage by receiving a detection signal from the power source 
detecting means 54. If the remote controller 3 has a set voltage, the 
routine is kept waiting at the ST4. If the remote controller 3 does not 
have the set voltage due to a stop of the power supply, the routine 
returns to step ST1. 
At the step ST3, when a set low voltage is detected so that the routine 
determines that the remote controller 3 is not being powered, a NEGATIVE 
flag is enabled and the unit 2 is activated to supply electric power to 
the remote controller 3. Then, the routine proceeds to a step ST5, where 
the power supply means 51 supplies power to the remote controller 3 which 
allows a signal to be sent and received between each indoor control unit 2 
and the remote controller 3. 
Then, the routine proceeds from the step ST5 to step ST6, where it 
determines whether there is any irregularity in the power supply, such as 
heteropolarity (i.e. cross polarity) or a short circuit detected by the 
overcurrent detecting means 53. Specifically, an overcurrent is created 
when the remote controller's 3 power supply source is heteropolar, or 
cross polarized, due to a connection error. When no heteropolarity is 
detected, the routine is kept waiting at step ST6. Conversely, when 
heteropolarity is detected, the routine proceeds from step ST6 to step 
ST7. At step ST7, the routine determines whether the error count N is not 
more than ten. When the error count N is more than ten, the routine 
proceeds to a step ST8. At the step ST8, the routine returns to the step 
ST1 by increasing the error count N by one. Thereafter, the 
above-mentioned operation is repeated and when the error count N is more 
than ten, a NEGATIVE flag is enabled at step ST7, so that an operation for 
irregularity is executed, and the power is turned off. 
The first embodiment ensures that power be supplied steadily to the remote 
controller 3 due to the pre-assignment of numbers to each of the indoor 
control units. Communication is therefore effectively initiated between 
the remote controller 3 and each indoor control unit 2. Consequently, the 
address of the indoor control unit 2 can be automatically set and the 
printed circuit boards of indoor control units 2 can be standardized, thus 
facilitating the production of the indoor control units 2. 
FIG. 9 shows a control flow of a power supply apparatus according to a 
second embodiment. In this embodiment, as shown in FIG. 6, a different 
timing means 21f is used in place of timing means 21c provided in the 
first embodiment. In addition, a fixed power supply means 21g and power 
supply determining means (or power activation means) 21h are provided 
instead of the power supply determining means (or power activation means) 
21d of the first embodiment. 
As shown in FIG. 8, the timing means 21f sets three different times for 
power supply designated by sectional numbers S1, S2 and S3, which are 
assigned to respective sectional bit codes into which the specific number 
S is divided per byte. In the first embodiment, the time of power supply 
based on the specific number itself becomes fairly long. Therefore, the 
times of power supply in this embodiment are reduced by dividing the 
sectional numbers S1-S3 per byte. 
The fixed power supply means 21g enables the power supply means 51 to 
supply electric power to the remote controller 3 at each of power supply 
times set by the timing means 21c. The power supply determining means (or 
power activation means) 21h enables the supply of electric power to the 
remote controller 3 when the fixed power supply means 21g properly 
supplies the power as per the sectional numbers S1-S3. 
FIG. 9 shows a flow diagram representing a power supply operation of the 
air conditioning indoor control unit 2 to power the remote controller 3 in 
accordance with a second embodiment of the present invention. When the 
power source is turned ON, a count N for sectional number is set to 1 at a 
step ST11, which is specifically set so that power is supplied as dictated 
by the first byte of the pre-assigned specific number. Then, when the 
routine proceeds to a step ST12, a fixed timer TM0 is set to a fixed time 
and a power supply timer TM1 is set to a time of power supply which is 
operated by multiplying the sectional number S1 of the first byte of the 
specific number by 10 ms. 
Subsequently, the routine proceeds to a step ST13 to determine whether the 
power source wiring 52 has a set voltage. This is done by receiving a 
detection signal from the power source detecting means 54 which determines 
whether electric power is being supplied from another indoor control unit 
2 to the remote controller 3. When the power source wiring 52 has a set 
voltage, which means that the remote controller 3 is being powered by 
another control unit 2, the control unit 2 is not enabled to supply 
electric power to the controller 3 and the routine returns to its main 
flow without supplying electric power to the remote controller 3. 
Conversely, at step ST13, when the power source wiring 52 does not have a 
set voltage, the remote controller 3 is not receiving electric power and 
the routine proceeds to step ST14. At step ST14, the routine determines 
whether the time of the power supply timer TM1 has been reached based on 
the sectional number S1 of the first byte of the pre-assigned control unit 
2 specific number. Subsequently, the routine returns to step ST13 until 
the time of the power supply timer TM1 has been reached. At this time and, 
as long as no other indoor control units 2 supply electric power, the 
routine proceeds from the step ST14 to a step ST15, and the fixed power 
supply means 21g begins to supply electric power. 
At this point, the routine proceeds to step ST16 where it determines 
whether the power source is heteropolar (i.e. cross polarized) or whether 
the power source is short-circuited. Specifically, as in step ST6 in the 
first embodiment, the routine determines whether the power source is 
heteropolar by receiving the detection signal from the overcurrent 
detecting means 53. When the power source is heteropolar, the routine 
proceeds from step ST16 to step ST17, where the power supply stop means 
(or power interrupting means) 21e disables the power supply of the fixed 
power supply means 21g and the routine proceeds directly to step ST18, 
without going through step ST17. If no heteropolarity is detected, the 
routine proceeds from the step ST16 to step ST18. 
At the step ST18, the routine determines whether the time of the fixed 
timer TM0 has been reached. Specifically, it determines whether the fixed 
power supply means 21g supplies electric power for a given pre-arranged 
time. The routine returns to step ST16 until the time of the fixed timer 
TM0 is reached, and then the routine proceeds from step ST18 to step ST19. 
Subsequently, the count N of the sectional number increases by one and the 
routine proceeds to step ST20, where the routine determines whether the 
count N of the sectional number is 3. Specifically, the routine determines 
whether electric power is supplied based on each one of sectional numbers 
formed from three bytes in the specific number. At this point, the 
electric power is supplied as per the sectional number S1 of the first 
byte, and the routine returns from step ST20 to step ST11 in order to 
supply electric power based on the sectional number S2 of a second byte. 
Thereafter, the same operation is executed for the sectional number S2 of 
the second byte. When another indoor control unit 2 supplies electric 
power prior to the S2 power supply, the routine determines that the S2 
unit will not supply electric power. 
When the above-mentioned operation has been executed for each of the three 
bytes sectional numbers S1-S3 of the pre-assigned control units 2 specific 
numbers, and when the power supply terminates without irregularities, the 
routine proceeds to step ST21. At this point, the count N for sectional 
number returns to 1 so that the routine returns to step ST11. Then, the 
unit is enabled to supply electric power from the power supply means 51 to 
the remote controller 3. 
Further, if heteropolarity of the power source is detected at step ST17, 
the routine returns from step ST21 to step ST12 and electric power is 
supplied repeatedly based on each of three bytes of the sectional numbers 
S1-S3. 
Therefore, as in the first embodiment, each address of the indoor control 
unit 2 can be automatically set, and printed circuit boards of the air 
conditioning control units 2 can be standardized. Further, the control 
unit 2 designated to supply electric power to the remote controller 3 can 
be timely selected, since the time of power supply is set by means of 
dividing the specific pre-assigned number into plural sections. 
FIG. 13 shows a control flow of an electric power supply apparatus 
according to a third embodiment. This embodiment, as shown in FIG. 10, 
features power supply notice means 21i and a second power control means 
(or no-power-supply means) 21j, in addition to the apparatus provided in 
the second embodiment. The power control means (or no-power-supply means) 
21b in the second embodiment is the first power control means (or 
no-power-supply means) 21b of this embodiment. 
The power supply circuit 5 has square wave generation means 55 connected 
between power source wirings 52 and the micro-computer 21, and it also 
features a comparator 56. The square wave generation means 55 generates 
square waves (notice signals) with a previously set voltage in the same 
direction. The comparator 56 is connected to reference voltage generation 
means 57. When another indoor control unit 2 outputs a square wave as a 
notice signal, the comparator 56 detects the notice signal and sends a 
detection signal to the microcomputer 21. 
The power supply notice means 21i sends the notice signal to the square 
wave generation means 55 when the fixed power supply means 21g supplies 
electric power. The second power control means (or no-power-supply means) 
21j determines to not supply electric power to the remote controller 3 
when another indoor control unit 2 receives a notice signal from the 
comparator 56. 
As in the second embodiment, when the specific number S is divided into 
three sectional numbers S1-S3, the possibility of simultaneous enabling of 
control units 2 to supply electric power may arise, during the number 
selection of the three sectional numbers by the fixed power supply means 
21g. Specifically, there may be a case that four indoor control units 2 
have different specific numbers S from one another, wherein the first 
indoor control unit 2 shown in FIG. 11(a) and the fourth indoor control 
unit 2 shown in FIG. 11(d) are connected to a positive polarity, while the 
second indoor control unit 2 shown in FIG. 11(b) and the third indoor 
control unit 2 shown in FIG. 11(c) are connected to a negative polarity. 
As shown in FIG. 12, when the first indoor control unit 2 and the second 
indoor control unit 2 execute respective power supplies PS as per 
respective sectional numbers S1 of the first byte, these power supplies PS 
are simultaneously enabled, thus colliding with each other. Then, 
regarding the first byte, the power supply of the third indoor control 
unit 2 collides with that of the fourth indoor control unit 2. Regarding 
the second byte, the power supply of the first indoor control unit 2 
collides with that of the third indoor control unit 2, and the power 
supply of the second indoor control unit 2 collides with that of the 
fourth indoor control unit 2. Regarding the third byte, the power supply 
of the first indoor control unit 2 collides with that of the second indoor 
control unit 2 and the power supply of the third indoor control unit 2 
collides with that of the fourth indoor control unit 2. 
Therefore, when the power supply stop means (or power interrupting means) 
21e detects each collision of the power supplies PS and the fixed power 
supply means 21g it repeats the power supply PS based on the time of power 
supply of the timing means 21f, and the unit for supplying electric power 
may not be determined. To meet the above situation, the above-mentioned 
square wave is sent as a notice signal so that an indoor control unit's 2 
power supply PS is selected to supply electric power with respect to each 
byte. 
FIG. 13 illustrates a flow chart of a power supply operation from an indoor 
air conditioning control unit 2 to the remote controller 3. The operation 
of the power supply in this embodiment has a step ST31 instead of the step 
ST15 of the second embodiment, and a step ST32 provided between the step 
ST12 and the step ST13. The other procedures are the same as in the second 
embodiment. 
Specifically, at step ST31, when the fixed power supply means 21g begins to 
supply electric power, the square wave generation means 55 outputs a 
notice signal of a square wave. With the notice signal, the other indoor 
control units can detect that a single indoor control unit 2 has started 
supplying power to the remote controller 3. 
At step ST32, the routine determines whether another indoor control unit 2 
is sending the notice signal, based on the detection signal from the 
comparator 56. If so, the unit is not enabled to supply electric power and 
the routine returns to a main flow without powering the remote controller 
3. When no other indoor control units 2 send the notice signal, the 
routine begins at step ST13. 
As shown in FIG. 12, when the power supplies PS begin supplying power 
simultaneously, the indoor control units 2 shown in FIG. 12(c) and FIG. 
12(d), which enable power supplies PS as per the sectional numbers S1 at 
the first byte, are deemed to be units which will not supply electric 
power as per the notice signals sent from the indoor control units 2 and 
shown in FIG. 12(a) and FIG. 12(b). The indoor control unit 2 shown in 
FIG. 12(b), which enables the power supplies PS as per the sectional 
numbers S2 at the second byte, is deemed to be a unit which does not 
supply electric power according to the notice signal from the indoor 
control unit 2 shown in FIG. 12(a), so that a single indoor control unit 2 
is determined to be a unit which supplies the power. 
Therefore, as in the second embodiment, each address of the indoor control 
unit can be automatically set, and printed circuit boards of the air 
conditioning control units 2 can be standardized. Further, since the power 
supply is identified, the unit supplying power can be determined without 
error, based on a difference between the specific numbers even if the 
power supply of the fixed power supply means 21g supplies power 
simultaneously with another indoor control unit 2. 
It should be noticed that the embodiments described above can apply to any 
supply of power from an air conditioning control unit to a controller. 
Also, the time at which the controller shall be powered is not restricted 
to the time mathematically obtained by multiplying the sectional number by 
10 ms. 
Industrial Applicability 
This invention is advantageous to standardize the power supplied from an 
air conditioning control unit to a remote controller, since the air 
conditioning control unit for supplying electric power to a controller is 
automatically predetermined.