JPS60240941A - Controller of air conditioner - Google Patents

Abstract

PURPOSE:To reduce drastically the number of times of defrosting and to improve comfortability at the time of heating operation by preventing fosting under terms wherein atmospheric temperature is comparatively high, by turning an outdoor blower at a very small number of revolutions without suspending the same at the same at the time of heating at overload. CONSTITUTION:A control circuit 8 is so constituted that an outdoor blower 6 is turned at the minute number of revolutions by an input signal from a heating load detector 7 at the time of heating at superload by a method wherein the heating laod detector 7 detecting a heating load and a contol circuit 8 controlling the number revolutions of the outdoor blower 6 are provided. In other words, at the time of heating operation, time when the temperature of an indoor heat exchanger 4 has become more than T2 (e.g. 55 deg.C) is detected by a thermistor 17 and an air quantity signal which is ultraminute is applied from an output port OUT5 of a main control circuit 19.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a control device for an air conditioner having a heat medium compression cycle.

<Prior art> Conventionally, a compressor that discharges a heat medium, an outdoor heat exchanger connected to the compressor via a flow path switching valve, and a negative side connected to the outdoor heat exchanger and the other side connected to the outdoor heat exchanger and the other side connected to the outdoor heat exchanger through a flow path switching valve have been used. A heat medium compression cycle is composed of an indoor heat exchanger connected to a compressor via a valve,
In an air conditioner that has an outdoor blower for forcibly blowing air to the outdoor heat exchanger and is capable of heating, cooling, and defrosting operations by switching the flow path switching valve, the conditions shown in Figs. 5 and 6 occur when heating is overloaded. If the temperature of the indoor heat exchanger becomes 12 or more (for example, 55℃ or more) or the load current becomes 12 or more (for example, 18A or more), the outdoor blower is stopped, the compressor is prevented from overloading, and the high pressure is It was preventing it from rising.

However, with this control method, even though the outside temperature is high, frost builds up while the outdoor blower is stopped, and the defrosting thermostat switches to, for example, -3°C, switching the heat medium compression cycle to the cooling cycle and starting the defrosting cycle. There was a possibility of entering. As a result, the frequency of generation of heating medium noise during cycle switching increased, and discomfort caused by a drop in room temperature also increased.

<Purpose> In view of the above, the present invention has the following advantages: By rotating an outdoor fan at a minute rotation speed without stopping it during heating overload,
Provides an air conditioning control device that can prevent frost formation under relatively high outside temperatures, greatly reduce the number of defrost operations, and improve comfort during heating operation. This is what I am trying to do.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings. This includes a compressor 1 that discharges a heat medium, and an outdoor unit connected to the compressor 1 via a flow path switching valve 2. A heat medium compression cycle 5 is composed of a heat exchanger 3 and an indoor heat exchanger 1 whose negative side is connected to the outdoor heat exchanger 3 and whose other side is connected to the compressor 1 via the flow path switching valve 2. , an outdoor air blower (6) for forcibly blowing air to the outdoor heat exchanger 3, and an air conditioning system (with a heating/cooling/defrosting operation power) by switching the flow path switching valve 2. @ A heating load detection device 7 that detects the room load is provided, and a control circuit 8 that controls the rotation speed of the outdoor air blower (6) is provided, and the control circuit 8 is configured to The outdoor blower 6 is configured to rotate at a minute rotational speed during heating overload.

1 and 2 are circuit diagrams of a control device according to the present invention, and 9 in the figure
is a power supply, 10 is an indoor blower, lla, ] 2a.

13a are compressors (1, flow path switching valve 2, indoor blower 1), respectively.
This is a relay contact that turns 0 ON.

The heating load detection device M7 detects the compressor 1 from the power source 9.
, a load current detection circuit 16 that detects load current in the AC circuits 1 and 1 that supply current to the flow path switching valve 2, indoor blower 10, outdoor blower 6, etc., and a heat detector that detects the temperature of the indoor heat exchanger 4. It consists of an exchanger thermistor 17 and an A/D converter 18 that converts an analog signal from the thermistor 17 into a digital value and outputs it to the control circuit 0.

The control circuit 8 also includes one main control circuit that outputs a signal to set the outdoor fan 6 to "strong" or "ultra-low" in response to an input signal from the heating load detection device 7, and a signal from the main control circuit 19. The triac circuit 21 is comprised of a phase control circuit 20 which outputs a trigger signal by three signals, and a triac circuit 21 which controls the rotation speed of the outdoor blower 6 by one signal from the phase control circuit 2 ( ).

Note that X, Y, and Z in FIG. 1 are the X in FIG. 2, respectively.

)', electrically connected to Z, 22 is a transformer,
23 is a bridge type rectifier circuit (including smoothing). The main control circuit 19 is a general one-chip microcomputer with a program ROM and data R.
It has AM, ALU and input ports IN1-6 and output ports 0UT1-7, and is driven by an external oscillation circuit 24. 25° and 26 are switches for the IN of the main control circuit 19.
I, input to INS. 27 is a defrosting thermostat for detecting the temperature of the outdoor heat exchanger 3, and is connected to the INS of the main control circuit 19.
is input. 28 is an indoor thermistor, which is converted into a digital value by an A/D converter 29 and sent to I of the main control circuit 19.
Input to NS. In addition, the heat exchanger thermistor 17
The temperature signal is converted into a digital value by the A/D converter 18 and input to IN6 of the main control circuit 19. 30 is a driver array, which drives relay coils 11, 12, and 13 by output signals from output capacitors OLJTI-3.

In addition, from the main control circuit 19 to the phase control circuit 20, an air volume signal of 1 strong from the outdoor fan 6 is output from the output capo OUT 4, and an air volume signal "ultra small" is output from the output capo OLJ T5. The output capacitors OUT 6.7 output signals corresponding to the power supply frequencies (50 Hz, 60 Hz), respectively.

On the other hand, the phase control circuit 20 receives the current signal of the outdoor blower 6 from the triac circuit 21, and after passing through the phase corresponding to the air volume signal from the main control circuit 19, the phase control circuit 20 receives the current signal of the outdoor blower 6, and after passing through the phase corresponding to the air volume signal from the main control circuit 19, a triac circuit 21 turns on the triac 21A of the triac circuit 21. It outputs one signal. That is, the phase control circuit 20
A comparator 31 is provided, and a negative input terminal of the comparator 31 is connected to a resistor 32 and an output capacitor (OUT4) of the main control circuit 19.
Resistors 33 and 34 having different resistance values are connected in parallel, and a voltage divided by the parallel resistance and the resistor 35 is applied. In addition, the positive input terminal of the comparator 31 is connected to the resistor 3 connected to the output port 7 of the main control circuit 19.
6 (5082 hours), resistor 37 (61'l Hz), resistors 38, 41, 44, capacitor 4 (), phototransistor 42A of first photocoupler 42, transistor 43,
and resistor 44 are connected, and resistor 36 (5 (at 'lHz)
Alternatively, a charged voltage is applied to the capacitor 40 through the resistor 37 (at 60 Hz). Note that when the resistor 36 has a larger value than the resistor 37, that is, 5 (lHz), the charging time becomes longer.

Then, the voltage is applied to the triac circuit 21 as shown in FIG.
When the outdoor fan 6 is energized by the signal from . Therefore, the positive input terminal of comparator 31 is at a low level voltage. Then, when the current of the outdoor fan 6 becomes zero and the triac 21A of the triac circuit 21 turns OFF, the phototransistor 42A turns ONL and the transistor 4
3 becomes OFF, and the capacitor 40 starts charging.

Therefore, when the voltage at the plus input terminal of the comparator 31 becomes higher than the input voltage at the minus input terminal, the output of the comparator 31 becomes H level, causing a base current to flow through the transistor 48 through the resistor 45 and diode 46. Therefore, the transistor 48 turns ON and causes the light emitting diode 5() of the second photocoupler 50 to emit light, outputs a trigger signal as shown in FIG. 4, and turns on the phototriac 5()B of the triac circuit 21. In addition, 45.47
．． 49 is a resistance.

Further, the triac circuit 21 turns on the triac 21A by a trigger signal from the phase control circuit 2 (), turns on the outdoor fan 6, and transmits the current cutoff signal of In other words, the triac circuit 2] is connected to the gate of the triac 2]A, and the triac circuit 50B of the second photocoupler 50 is connected to the gate of the triac 2]A. When the internal LED of the triac 50B is turned on by the trigger signal from the phase control circuit 2(), the internal triac is turned on, and a gate current flows through the resistor 51 and the phototriac 50B to the triac 2]A, turning it on. In addition, 51 in the figure
is a resistor, and 53 is a capacitor. In addition, when the triack 21A is OFF, the voltage of the AC power supply 9 is lower than the voltage of the outdoor blower 6.
It is applied to the light emitting diode 42B of the first photocoupler 42 through the resistor 52 and the diode bridge 53 to cause it to emit light, and outputs an outdoor blower current cutoff signal to the phase control circuit 2(').

In the configuration described in item 1, during heating operation, the heat exchanger thermistor 17 detects when the temperature of the indoor heat exchanger 4 becomes T2 (for example, 55°C) or higher, or the load current detection circuit 1
6, it is detected when the load current becomes 12 (ampere 1 or more), and these detection signals control the output port of the main control circuit 19.
) A [ultra-fine] air volume signal force is applied from OUT5. In addition, during heating operation, if the temperature of the indoor heat exchanger 4 is below T2 and the load current is below 12, the output from the main control circuit 19 is
“Strong” air volume signal force is applied.

In the phase control circuit 20, as described above, a voltage with a constant waveform is applied to the positive input terminal of the comparator 31, and the resistor 33 is applied to the negative input terminal by the air volume signal from the main control circuit 19. Alternatively, voltages of different levels are applied depending on the difference in the resistance value of the 34 resistors. Therefore, comparator 31
The timing at which the output reaches the H level differs, and the timing at which the single signal is output from the light emitting diode 50A of the second photocoupler 51) also differs depending on whether the air volume signal is "strong" or "ultra-fine."

That is, the outdoor blower current is controlled by the timing control of the trigger signal input to the triac circuit 21. For example, if the trigger signal is inputted to the triac circuit 50.8 at an early point in time, a large amount of current flows and the outdoor blower 6 is In addition, if one signal is input to the bird at a late point in time as shown in FIG. 4, the outdoor blower 6 will rotate with a "super light wind" because the current will be small. And 70- in Figure 1 ()
As shown in the chart, when the temperature of the indoor heat exchanger becomes T1 or less and the load current becomes 11 or less as shown in FIG. The outdoor blower 6 is switched to strong wind and the heating operation is continued.

In addition, Fig. 7 is a diagram showing the relationship between the torque and rotation speed of the electric motor of the outdoor blower 6. If the electric motor is used according to the load curve in the figure and the phase is controlled as described above, it will be possible to generate a 60 Hz ultra-light breeze. It is possible to prevent the rotational speed from dropping too low, and it is also possible to use the current speed switching tap of the motor (1). The ultra-light rotation may be performed at a rotation speed that does not affect the protection device of the compressor 1, for example, by shifting down to 150 to 20 (1 rpm).

Moreover, FIG. 31 is a diagram showing the relationship between the rotation speed and the cutoff phase angle of the outdoor blower 6. By changing the cutoff phase angle, commercial power sources (5(')H2 and 6(-)) (z )
Either of these can be achieved by making the rotational speed of the outdoor blower 6 the same. That is, in the phase control circuit 20, as in the above embodiment, the resistance value of the resistor 36 (50HzZ) is
If the value is larger than 7 (6 (lHz)), the charging time will be longer at 50 Hz, and the voltage waveform ■ (10) applied to the positive input terminal of the comparator 31 will be as shown in Fig. 4. However, the current waveform of the outdoor fan 6 shown in the upper part of Figure 4 is also 5 (1Hz), which has a longer wavelength, so even if the trigger signal is delayed, the same amount of current will be generated. Electric current can be supplied to the outdoor blower 6.

<Effects> As is clear from the above description, the present invention includes a compressor that discharges a heat medium, an outdoor heat exchanger connected to the compressor via a flow path switching valve, and a negative side connected to the outdoor heat exchanger. A heat medium compression cycle is constructed from an indoor heat exchanger connected to 1, and an outdoor blower for forcibly blowing air to the outdoor heat exchanger. In an air conditioner capable of performing heating-cooling and defrosting operation by switching a flow path switching valve, a heating load detection device for detecting a heating load is provided, and a control circuit for controlling the rotation speed of the outdoor blower is provided. The control circuit is configured to rotate the outdoor blower at a minute rotational speed in the event of heating overload based on a human power signal from the heating load detection 11-device.

Therefore, according to the present invention, by rotating the outdoor fan at a minute rotation speed without stopping it during heating overload, frost formation can be prevented under conditions where the outside temperature is relatively high, and the number of times of defrosting can be increased to 11. This has the effect of reducing the amount of heat and improving comfort during heating operation.

[Brief explanation of the drawing]

Fig. 1 is a control circuit diagram showing an embodiment of the present invention, Fig. 2 is a circuit diagram showing a main control circuit and a phase control circuit of the control circuit, Fig. 3 is a configuration diagram of the air conditioner, The figure shows the main waveforms of each part of the triac circuit and phase control circuit, $5
The figure shows the relationship between the indoor heat exchanger temperature and the outdoor fan, Figure 6 shows the relationship between the same load current and the outdoor fan, Figure 7 shows the relationship between the outdoor fan's rotation speed and torque, and Figure 8 9 is a diagram showing the rotation speed and cutoff phase angle characteristics of an outdoor blower, FIG. 9 is a conventional control flowchart, and FIG. 10 is a control flowchart according to the present invention. 12- 1: Compressor, 2: Flow path switching valve, 3: Outdoor heat exchanger, 4:
Indoor heat exchanger, 5: heat medium compression cycle, 6: outdoor blower, °7: heating load detection device, 8: control circuit, 16: load current detection circuit, 17: heat exchanger thermistor, 19: main control circuit, 20: Phase control circuit, 21: Triac circuit. Application filed Sharp Corporation Agent Tsunehisa Nakamura

Claims (1)

[Claims] A compressor that discharges a heat medium, an outdoor heat exchanger connected to the compressor via a flow path switching valve, and a negative side connected to the outdoor heat exchanger and the other side connected to the compressor via the flow path switching valve. A heat medium compression cycle is constructed from the indoor heat exchanger, which is connected to the outdoor heat exchanger, and has an outdoor blower to forcefully blow air to the outdoor heat exchanger. In an air conditioner that can be operated, a heating load detection device for detecting a heating load is provided, and a control circuit for controlling the rotation speed of the outdoor blower is provided, and the first control circuit is operated by human power from the heating load detection device. 1. A control device for an air conditioner, characterized in that it is configured to rotate one outdoor blower at a minute rotational speed when a heating overload occurs from a second signal.