JPS5930973B2 - Air conditioner control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a signal transmission system between the indoor and outdoor units of an air conditioner configured with an indoor unit and an outdoor unit.

More specifically, by using a multiplex transmission method for transmission between indoor and outdoor units, the following drawbacks of the conventional method are attempted to be overcome.

In recent years, as LSI devices such as microcomputers have become available at relatively low prices, air conditioner control devices are becoming increasingly popular.
With the introduction of these LSis, there is a transition from conventional electromechanical control to so-called electronic control.

An example of an electric circuit of an air conditioner using such a so-called electronic control device is shown in FIG.

In Figure 1, 1 is an indoor unit, and operation switch 1
01, ventilation fan motor 102, heating auxiliary heater 103
, the speed of the blower fan motor 102 and the auxiliary heater 1
03 is controlled on and off according to the driving mode via contacts 111 and 112 that turn on and off, and
Outdoor unit controller 21 provided in the second outdoor unit
0, the compressor motor 201 and the blower fan motor 20
2 and the four-way valve 203.

The controller 110 includes sensors such as a room temperature detector and an indoor unit status detector (a heat exchanger temperature sensor and an air outlet temperature sensor), a heating/cooling switch operated by the user, and a room temperature setting device and other control switches. It includes mode determining means such as a microcomputer for determining the operating mode of the air conditioner based on the information and the information from the outdoor unit controller 210.

2 is an outdoor unit that includes a compressor motor 201, a blower fan motor 202, and a four-way valve 203 for switching between cooling and heating;
Contact 21 controlled by the outdoor unit controller
On/off control is performed by 1, 212, and 213.

The outdoor unit controller 210 is the indoor unit controller 11
Regarding the information sent from 0, contacts 211 and 212
It includes a logic circuit that controls on/off of the contact 213 and a de-icer that controls the contact 213.

3 is a commercial power supply.

81 to 4 are signal transmission lines, for example, Sl is for turning on and off the compressor motor 201, S2 is for turning on and off the four-way valve, S3 is for defrosting operation, and S4 is for common potential.

The deaiser takes the configuration shown in FIG. 2, for example.

This de-icer is a standby type de-icer, and the thermostat 2 includes the outdoor unit heat exchanger temperature detection thermistor 215H.
15, a first timer 216, a second timer 217, a logic circuit 218, and a relay 213C.

If heating operation is started, a heating signal is transmitted from the indoor unit controller 110 to the outdoor unit controller 210 using 82.

This signal causes the outdoor unit controller 210 to
is closed, the four-way valve 203 is turned on, and the refrigeration cycle becomes a heating cycle.

Simultaneously with the start of heating in the heating cycle, the first timer 216 of the de-iser starts operating, and prohibits the operation of the thermostat 215 for a certain period of time Ti.

When the outdoor heat exchanger temperature decreases due to frost formation due to continued heating operation over Ti, this causes the thermistor 21
5H is detected, the thermostat 215 operates, and the relay coil 213C is energized through the control circuit 218.
The contact point 213 is turned off, the four-way valve 203 is turned off, and the cycle is switched to the cooling cycle, and the outdoor fan motor 202 is stopped to enter defrosting operation.

At the same time, the information is transmitted to the indoor unit controller 110 via 83, and the fan motor 102 is controlled to the lowest speed and the heater 103 is forcibly turned on in order to prevent cold draft from occurring in the indoor unit during defrosting operation.

At the start of the defrosting operation, the control circuit 218 of the deicer
The second timer 217 is triggered and control is performed to raise the reference level of the thermostat to the return level.

Defrosting is completed when the heat exchanger temperature detected by the thermistor 215H rises to the elevated reference level of the thermostat, or the time Tt set by the second timer, whichever is earlier.

When defrosting is completed, the control circuit 218 switches the relay coil 21
3C is stopped, the contact 213 is closed, and the normal heating cycle is resumed. At the same time, the indoor unit controller 110 cancels the defrosting operation of the fan motor 102 and the heater 103.

An advantage of such a configuration is that since the outdoor unit 2 is provided with a relay that controls the contacts 211 and 212, the space of the indoor unit 1 can be reduced.

However, on the other hand, the de-iser has a configuration as shown in FIG. 2, and in particular, the time Ti of the first timer 216 is relatively long, from 60 minutes to 2 hours, so if this was realized with an electronic circuit, a corresponding amount of space would be required. On the contrary, the outdoor unit 2 must be made thicker.

In addition, the number of connection lines between the indoor units 1 and 2 is large, and workability is poor.

The present invention solves the above-mentioned drawbacks, and makes the standby de-iser, outdoor fan, four-way valve, compressor, etc. controlled by the same controller, making it compact, and also connects the indoor unit using a signal transmission path with a small number of wires. This control device connects the controller and the outdoor unit controller at a discrete DC level, and transmits signals for starting and ending defrosting operation from the outdoor unit controller to the indoor unit controller as pulse signals.

FIG. 3 is an electrical circuit diagram in one embodiment of the present invention;
Indoor unit controller 110 and outdoor unit controller 210
It is divided into two parts and connected by a signal transmission path SD.

120 is a microcomputer that implements the first timer 216 and second timer 217 of the de-Icer shown in FIG. 2 by a program.

Output terminal Ti1 is 'Hi' only when cooling is on; 02 is 1H1" only when air conditioning is on; 3 is 'XH1' only when heating is on.
", 04 is "Hi" only when the heating is on, that is, defrosting is possible after the first timer setting Ti.

121-124 are open collector output inverters, and resistors 125-128 are provided as load resistances, respectively.

Assuming that the transmission level of the transmission line SD is Vs, this transmission level Vs is the output terminal 01 of the microcomputer 120.
It changes as follows depending on the state of ~04, that is, the driving mode.

(1) Cooling off, Vs-Vl: TJ1 to TJ4°-L
o jj, all inverters 121 to 124 are off, so Vl = Vc c (2) Cooling on, Vs = V2:01 chisel”H
i”, only the inverter 121 is turned on, (3) Heating off, Vs = v3: 021) and “Hi”.
"f, only inverter 122 is turned on, (4) Heating is on, Vs = V4", only 03 is at
At Hi pp, only the inverter 123 is turned on (5) defrosting is possible, Vs = V5'', only 04 is 'Hi'
”, only the inverter 124 is turned on, where vcc is the DC power supply voltage of the outdoor unit controller 210, Ro is the resistor 220, and R5-R8 are the resistors 125
~128 resistance values.

Now, the magnitude relationship of the signal level Vs is V 1 >V 2 >
Let Va>V4>V5.

As can be seen from the above explanation, this can be achieved by appropriately selecting the resistance value.

The outdoor unit controller 210 receives this transmission signal in the following manner and controls the contacts 211 and 212.

Vs is input to operational amplifiers 226 to 228 and an inverting input of a comparator 229 with an open collector output.

The reference input voltages of E1 to E4 are input to the non-inverting inputs of the operational amplifiers 226 to 228 and the comparator 229.

E1 to E4 are voltages obtained by dividing Vcc by resistors 221 to 225, and the magnitude relationship with Vs is V□〉El〉V2〉
It is set so that EI2>Vs>E3>V4>E4>v5.

(1) Cooling off, Vs = V1: Operational amplifier 226~
228, comparator 229 outputs are all tt Lo'''
Then, the outputs of the AND gates 23, 1 and the OR gate 232 become t Lo fij, the drivers 233, 234 are turned off, the relay coils 211C, 212C are not energized, the contacts 211, 212 are turned off, and the four-way valve 203 is turned off. The off refrigeration cycle is a cooling cycle, and when the compressor motor 201 is stopped, the cooling is turned off.

(2) Cooling on, Vs-v2: Only the operational amplifier 226 output becomes “Hi” and the inverter 230 output becomes “Hi”
Therefore, both the output of the AND gate 231 and the output of the OR gate 232 become "Hl", and the driver 233 is turned on.
Relay coil 211C is energized, contact 211 is turned on, compressor motor 201 is operated, and cooling is turned on.

Hereinafter, heating on/off and defrosting will be explained with reference to the timing chart of FIG. 4.

In the same figure, A indicates the transmission level Vs, the port indicates the outdoor heat exchanger temperature θ, C indicates the output of the thermostat 215, 2 indicates the state of the compressor motor 201, E indicates the state of the four-way valve 203, and the port indicates the monostable state. The outputs of the multivibrator 247 are shown respectively.

The heating is turned on and off from time tφ to tl in FIG. 4, and this period will be explained first.

(3) Heating off, vs=■3: Operational amplifier 226°2
The output of 27 becomes tt Hipp, and the inverter 230
Since the output is tr, 01M, both the AND gate 231 output and the OR gate 232 output are 'Lo''', the driver 233 is off, and the relay coil 211C is not energized.
Compressor motor 201 stops.

On the other hand, the driver 234 is turned on, the relay coil 212C is energized, the four-way valve 203 is turned on, and the refrigeration cycle becomes a heating cycle.

Therefore, the heating is turned off.

(4) Heating on, Vs = V4”, operational amplifier 226
All outputs of °227.228 become 'H1'.

As a result, the output of the OR gate 232 becomes "Hi", the driver 233 is turned on, the relay coil 211C is energized, the compressor motor 201 is operated, and heating is turned on.

From time to to tl, the heating is turned on and off as described above.

When the first timer time Ti has elapsed from the time to, if the outdoor heat exchanger temperature has decreased sufficiently, the defrosting operation starts.

From time t1 to t2, if the heating is on, Vs = V
5, and when the heating is off, it becomes Vs""Vs.

During this time, the heat exchanger temperature θ has not decreased to the frost detection temperature θL, so no defrosting operation is performed.

Deaisa's thermostat 215 is a bridge with a thermistor 215H as an outdoor heat exchanger temperature detector on one side of the bridge and resistors 215A-C on the other three sides.
It consists of an operational amplifier 215D that receives the bridge output, an inverter 215F that switches the detection level of the thermistor 215H to the frost detection temperature and the defrosting completion temperature, a hysteresis circuit consisting of a resistor 215E, and a driver 215G that operates with the output of the operational amplifier 215D. .

Operational amplifier 215D output t (Lo” to “Hi”
” with capacitor 241 and resistor 242, utn
The change from i" to t(Lo" is detected by the capacitor 244 and the resistor 245 via the inverter 215F, and the change is input to the monostable multivibrator 247 as a pulse generator via the OR gate 246. Ru.

It Hi" pulse holding time TH of the monostable multivibrator 247 is set by a capacitor 248 and a resistor 249.

Monostable multivibrator 247 output is diode 2
50, is applied to the transmission 2in SD via a resistor 252 and to the non-inverting input of the comparator 229 via a diode 251.

The positive pulse applied to the transmission line SD is transmitted through the resistors 129A to C1 comparator 1 in the indoor unit controller 110.
29D and input to the microcomputer 1200A power terminal 11.

(5) Heating off from time t1 to time t2, Vs
=V3'', V3)R4, so comparator 22
9 output is 'Lo' and the thermistor 215H is pulled, so the thermistor 215H has zero resistance, the detected temperature is frosting temperature 05 or higher, and the amplifier output is 'L'.
o", even if the heat exchanger temperature is below the frosting temperature, the defrosting operation is not performed.

(6) Defrosting operation, time t2, Vs=V5: Vs is v5
It becomes.

The heat exchanger temperature θ becomes frosted and reaches the level θL.

The comparator 229 output is open, and the operational amplifier 215D output changes from "P" to "Hi".

The driver 215G is turned on, the relay coil 213C is energized, the contact point 213 is opened, the four-way valve 203 and the blower fan motor 202 are turned off, and the refrigeration cycle becomes a cooling cycle and a defrosting operation is started.

The operational amplifier 215D output changes from tt Lo" to ' Hi
'', the positive pulse differentiated by the capacitor 241 and resistor 242 triggers the monostable multivibrator 247 via the OR gate 246, and the monostable multivibrator 247 outputs a signal THtu Hi jj times at a certain time.

If this -Hi jj times signal level is approximately equal to Vcc, the transmission level Vs becomes vD.

Here, R2 is the resistance value of the resistor 252.

Now, when Vl) = V 4 , Vs becomes the period V4 of TH.

Since Vs is applied to the non-inverting input of the comparator 129D, v4 is applied from time t2.

A voltage ED obtained by dividing the output of the microcomputer 04 by resistors 129A and 129C is applied to the non-inverting input of the comparator 129D.

Since defrosting is now possible, the 04 output is H1'', and the ED at this time is R4 (to do this, the resistor 129A
, 129C).

In the state where defrosting is possible, V s = V 5 (because R4,
The comparator 129D output is It L oj).

Also, when the 04 output is 'Lo''', the comparator 129D is an open collector output, and its output is the resistor 1.
Since it is pulled up to 04 via 29B, its output is (t L ojj).

At the start of defrosting, vS becomes TH period v4, and ■4>R4
Then, the output of the comparator 129D becomes 'Hi' and is input to the input terminal 11 of the microcomputer 120.

This allows the microcomputer 120 to recognize the start of the defrosting operation.

On the other hand, almost Vcc is applied to the non-inverting input of the comparator 229 of the outdoor unit controller 210 during the period TH, and the non-inverting inputs of the operational amplifiers 226, 227, 228 are also almost Vcc, and all of these outputs are -Hi.
Maintain Ifi.

('f) End of defrosting operation, time t4: Due to defrosting operation,
When the outdoor heat exchanger temperature O rises and reaches the defrosting end level θH at time t4, the output level of the operational amplifier 215D becomes '
Changes from ``Hi'' to ``Lo'', relay coil 213
C is not energized and contact 213 closes, turning on four-way valve 203 and returning to the heating cycle.

On the other hand, since the inverter 215F output changes from -Lon to H1'', this change causes the capacitor 244 and resistor 2
45, the monostable multivibrator 247 is triggered via the OR gate 246, and its output becomes the time T H''''H1'' level again, causing ■S to become V4.

As a result, the microcomputer 120
It receives the second "Hi" signal from 1 and recognizes that defrosting has been completed.

The microcomputer 120 connects ■4 terminals to Loj''
At the same time, the stone 3 or 12 is set to 'Hi', and the on/off of the heating operation is output.

At the same time, the built-in first timer is triggered again, and a normal heating on/off signal is output with T2 or T3 set to 'Hi' until Ti elapses.

If θ does not reach θH even after the second timer setting time Tt built in the microcomputer 120 has elapsed (in the case of the broken line in FIG. 4), at time t6, Tt has elapsed since t2, so The microcomputer 120 is ■
Change output 4 from "Hi" to t:t, 01M, and set 02 or 03 to "It Hi".

As a result, Vs changes from Vs to ■3 or ■4, the output of the comparator 229 becomes ``Lo'', and the thermistor 215H is shorted, so the output of the operational amplifier 215D changes from ``Hi'' to ttLo.

Due to this change, the output of the monostable multivibrator 247 becomes "Hi" for a certain period of time, and Vs becomes a voltage of 74 or more, but at this time, since 04 is t boIfi, the 11 terminal of the microcomputer 120 no longer has t(ni
” is not entered.

In addition, operational amplifiers 226 to 228, comparators 229
Since all the outputs are "Hi'", the heating is on at least during the period from time t6 to TH.

Further, the short circuit of the thermistor 215H is released, but since θ is higher than the frosting level θL (because it is immediately after the defrosting operation), the output of the operational amplifier 215D remains at -L oll.

FIG. 5 is an electric circuit diagram showing another embodiment of the present invention, and FIG. 6 is a timing chart thereof.

In the embodiment of FIG. 3, the discrete DC levels are defined as V 1 >
Although V 2 >v3>v4>Vs, the one in FIG. 5 is for the case where Vl<V2<V3<V4<v5.

In FIG. 5, the same numbers as in FIG. 3 indicate the same items.

The microcomputer 120B has, for example, P-MOS open-drain outputs, which are 01 to 04.

The meanings of the +H1jet Lo 13 signals at terminals 01-04 are the same as those in FIG.

Diodes 131 and 132 are added to prevent backflow.

The resistors 130A and 130C provide an appropriate ED, and in the case of this embodiment, are selected to have the relationship v4<E4<Vs.

The input to the comparator 129D is given in the opposite manner to that shown in FIG.

Furthermore, in the outdoor unit controller 210, the operational amplifier 226
~228, the way of inputting to the comparator 229 is also reversed to that in FIG.
The resistance values of the resistors 221B to 225B are selected so as to satisfy the following relationship: 3<V4<E4<V5.

Since the relationship between Vs and En is opposite to that shown in Fig. 3, an open collector output inverter 253 is added to the output of the monostable multivibrator 247, and the output of the monostable Malmöbibrake 253 starts defrosting. and t at the end
tHl'', the resistance 252B.

Through the diode 250, Vs is lowered from Vs to V4, and through the diode 251, Eu is brought to approximately zero V.

(1) Time tφ~t1: Heating operation on/off, ■
S becomes v3 or V4, the four-way valve 203 is turned on,
Compressor motor 201 is v3. Turns off and on according to V4.

(2) Time t2: At the start of defrosting operation, the monostable multivibrator 247 output becomes °°H1'', Vs changes from v5 to V4<E4, and tt Hipp is input to 11 of the microcomputer 120B.

(3) Time t4: Defrosting is completed, and "Hi" is input again to the microcomputer 120B in the same way as when defrosting is started.

The above operations are repeated to perform heating operation.

In the embodiments shown in FIGS. 3 and 5, the transmission level of the pulse signal at the start and end of defrosting is set to v4, but this is
Any level other than the defrost enable signal level v5 may be used.

In addition, the indoor unit 1 is also caused to perform a defrosting operation in synchronization with the defrosting operation of the outdoor unit 2, but in the case of a device in which only the start is synchronized, there is no need to transmit an end signal.

The air conditioner control device of the present invention enables two-way signal transmission between the indoor unit controller and the outdoor unit controller through the same signal transmission path, and allows bidirectional signal transmission between the indoor unit controller and the indoor unit controller. By using pulse signals for transmission, the discrete DC level that is the transmission signal from the indoor unit controller to the outdoor unit controller is only affected for a short time (pulse generation time), and the control of the outdoor unit is stable. It can be done by

In addition, since a thermostat, which is a frost detection device, is provided on the outside of the room, it is possible to accurately detect frost formation, and highly accurate control is possible.

[Brief explanation of drawings]

Fig. 1 is an electrical circuit diagram of an air conditioner using a conventional control device, Fig. 2 is a block diagram of a standby de-icer, and Fig. 3 is an electrical circuit diagram of the main parts of an air conditioner control device according to an embodiment of the present invention. 4 is a timing chart of the circuit shown in FIG. 3, FIG. 5 is an electrical circuit diagram of a main part of a control device according to another embodiment of the present invention, and FIG. 6 is a timing chart of the circuit shown in FIG. 5. It is a diagram. 1...Indoor unit, 2...Outdoor unit, 110...Indoor unit controller, 120
, 120B...Microcomputer, 210
...Outdoor unit controller, 215...
Outdoor heat exchanger thermostat for standby de-iser, 216
....First timer for standby type de-icer, 217.
...Second timer for standby type de-icer, 247...
...Monostable multivibrator.

Claims (1)

[Claims] 1 An air conditioner consisting of an indoor unit and an outdoor unit includes a controller provided in the indoor unit, a controller provided in the outdoor unit, and a signal transmission path between each of the controllers, and the indoor unit controller is on standby. a control unit comprising at least a first timer of the mold de-icer and outputting a signal for controlling at least a compressor, an outdoor fan, and a four-way valve in the outdoor unit and an output signal of the first timer; a DA converter that converts the output signal of the DA converter into a discrete DC level, and a pulse detection section that detects a pulse signal on the signal transmission path and outputs it to the control section, and the outdoor unit controller is connected to the DA converter. an AD converter that receives a digital signal having a one-to-one relationship with the original signal from the analog signal transmitted via the signal transmission path, and a defrosting operation starts when the outdoor heat exchanger reaches a set temperature; An air conditioner configured to include a thermostat that inverts an output level for termination, and a pulse generator that outputs a pulse signal that is transmitted to the pulse signal detection unit via the signal transmission path when the output level of the thermostat is inverted. Control device for harmonizer.