JP2001099460A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cut of useless power consumption by a bleeder resistor while a constant current consumption circuit is not required by switching on and off the current flowing the constant current consumption circuit for stabilizing the drive current of the control circuit of an air conditioner. SOLUTION: The air conditioner is provided with a means of switching the current flowing a current stabilizing circuit according to the operating state of the air conditioner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current stabilizing circuit for stabilizing a driving current of a control circuit of an air conditioner.

[0002]

2. Description of the Related Art A conventional air conditioner will be described below with reference to FIG.

As shown in FIG. 4, a conventional air conditioner is
An indoor unit 4 having a switch 3 for controlling the power supply to the AC power supply 1 and the outdoor unit 2, a diode bridge 5 for converting an AC voltage supplied from the indoor unit 4 into a DC voltage, and a load 5 such as a fan motor. A constant current consuming circuit 10 having a control circuit 6 for controlling the power supply, a transforming means 7 for supplying power to the control circuit 6, and a first bleeder resistor 8 and a second bleeder resistor 9 for stabilizing the output voltage of the transforming means 7 And consisted of

The control of the air conditioner configured as described above will be described with reference to FIG. At the start of operation, the AC voltage 1 is applied to the outdoor unit 2 from the switch 3 of the indoor unit 4,
Rectification is performed by the diode bridge 5, and the DC voltage is converted by the transformer 7 into a voltage required by the control circuit 6. At that time, so that the power supply voltage of the control circuit 6 becomes stable,
A constant current is consumed by a constant current consumption circuit 10 in which a bleeder resistor 8 and a bleeder resistor 9 are connected between the power supply and the ground.

Another conventional example is disclosed in Japanese Patent Application Laid-Open No. 7-337.
A configuration having a load current detecting unit as disclosed in Japanese Patent Laid-Open No. 007 is also known.

[0006]

However, in the above-described conventional configuration, the constant current consumption circuit 10 constantly consumes current, and the output voltage of the transformer 7 is relatively high when the motor is driven at a relatively high load. Are stable, and even in a state where the constant current consuming circuit 10 is not required, the constant current consuming circuit 10 consumes useless power.

Further, in the configuration as disclosed in Japanese Patent Application Laid-Open No. 7-337007, complicated load current detecting means is required, and the problem remains in terms of cost.

An object of the present invention is to solve the above problems and to provide a highly efficient air conditioner with a simpler circuit configuration.

[0009]

In order to solve the above-mentioned problems, the present invention provides means for turning on / off the connection of a constant current consuming circuit according to a control state such as driving of a fan motor. , Without providing a negative overcurrent detection means,
The current consumption of the control circuit can be stabilized, and unnecessary power during operation can be eliminated.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 is provided with a constant current consuming means for stabilizing a drive current according to a control state of a control circuit. With this configuration, the drive current of the control circuit can be stabilized regardless of the load.

According to a second aspect of the present invention, the constant current consuming means comprises a fan motor drive detecting circuit and a constant current consuming circuit. With this configuration, it is possible to ensure the minimum necessary drive current of the control circuit by the constant current consumption circuit when there is no load.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, an indoor unit 14 includes an AC power supply 1.
1 and a switch 13 for controlling power supply to the outdoor unit 12. Further, the outdoor unit 12 includes a diode bridge 23 that converts the AC voltage supplied from the indoor unit 14 into a DC voltage, and a transformer 18 that converts the DC voltage converted by the diode bridge 23 and supplies the DC voltage to the control circuit 16. And a control circuit 16 for controlling a load 15 such as a fan motor, and a constant current consumption circuit 17 for stabilizing the current consumption of the control circuit 16 according to the control state of the load 15.

The operation will be described below with reference to FIG. In FIG. 2, I is a current value at which the output voltage of the transformer 18 stabilizes accurately, Ia is the current consumption of the load A, Ib
Is a current consumption value of the load B.

The loads A and B in FIG. 1 are loads indispensable for the operation of the air conditioner, such as a compressor and an outdoor fan, and are sequentially driven at a predetermined timing. In the operation of the air conditioner, both the load A and the load B are finally driven, and the consumption current is the sum of the current Ia and the current Ib (Ia + I
b).

Therefore, when only the load A is being driven, only the first transistor 19 is turned on by the control signal output from the control circuit 16 and
-Ia current is consumed. When only the load B is driven, only the second transistor 21 is turned on by the control signal output from the control circuit 16, and the bleeder resistor 2 is turned on.
2 consumes the current of I-Ib.

Thereafter, when both the load A and the load B are driven, Ia + Ib becomes the same as the current I. Therefore, the control signal from the control circuit 16 controls the first transistor 19a.
And the second transistor 21 are turned off, and no current flows through the bleeder resistors 20 and 22.

At the time of no load, since the first and second transistors 19 and 21 are both turned on, a current that is the sum of the current consumption (I-Ia) of the load A and the current consumption (I-Ib) of the load B flows. .

By the above operation, no current flows through the bleeder resistors 20 and 22 during the operation of the air conditioner, the efficiency can be improved, and the output of the transformer 18 with the minimum necessary current during the transition period of the operation of the air conditioner. The voltage can be stabilized with high accuracy.

Hereinafter, another embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

In FIG. 3, the indoor unit 26 is provided with an AC power source 2.
3 and a switch 25 for controlling power supply to the outdoor unit 24.

The outdoor unit 24 includes a diode bridge 27 for converting the AC voltage supplied from the indoor unit 26 into a DC voltage, and a fan motor control circuit 28 for transforming the DC voltage converted by the diode bridge 27 to convert the DC voltage. , A fan motor drive circuit 33 composed of a diode 30, a fan motor switch 31, and a transistor 32, a resistor 34, a resistor 35, and a transistor 3.
6, a fan motor drive detection circuit 38 including a bleeder resistor 37, a resistor 39, a resistor 40, and a transistor 4.
1. Constant current consumption circuit 43 composed of bleeder resistor 42
, A fan motor 44 and a fan motor power supply 45.

The operation of the air conditioner having the above configuration will be described below. In FIG. 3, the transistor 32 is off.
At this time, the fan motor switch 31 is turned off. Therefore, the fan motor power supply 45 is not supplied to the fan motor control circuit 28, and the fan motor 44 is stopped.
At this time, the transistor 36 is turned off and the transistor 4
1 turns ON, and the bleeder resistor 42 of the constant current consuming circuit 43
And the output voltage of the transformer 29 is set to a predetermined voltage or less that does not exceed the withstand voltage of each component.

When the transistor 32 is ON, the fan motor switch 31 is turned ON, and the fan motor control circuit 28
Is supplied with a fan motor power supply 45. At this time, a voltage is generated across the diode 30 and the transistor 36 is turned on.
I do. When the transistor 36 is turned on, the transistor 4
No voltage is generated between the base and the emitter of the transistor 1, and the transistor 41 is turned off. Therefore, no current flows through the bleeder resistor 42 of the constant current consuming circuit 43, and the efficiency of the current consumed by the bleeder resistor 42 can be increased.

[0025]

As described above, according to the first aspect of the present invention, a constant current consumption circuit for predicting a drive current of a load according to a control state of a load of an outdoor unit and stabilizing a current consumption of a control circuit is provided. , Which consumes only the minimum necessary current, achieves high efficiency, and can provide an accurate output voltage.

According to a second aspect of the present invention, a fan motor drive detection circuit for detecting drive of a fan motor and a constant current consumption circuit are provided, so that a voltage can be reduced with a very simple circuit configuration. It can be less than or equal to a predetermined value, and high efficiency can be achieved.

[Brief description of the drawings]

FIG. 1 is a control circuit block diagram of an air conditioner showing one embodiment of the present invention.

FIG. 2 is an output voltage characteristic diagram of a transformer in one embodiment of the present invention.

FIG. 3 is a control circuit block diagram of an air conditioner showing another embodiment of the present invention.

FIG. 4 is a control circuit block diagram of a conventional air conditioner.

[Explanation of symbols]

 12 outdoor unit 13 switch 14 indoor unit 15 load 16 control circuit 17 constant current consumption circuit 18 voltage transformer 38 fan motor drive detection circuit 43 constant current consumption circuit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takato Ueshima 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Yuji Tani 1006 Kadoma Kadoma, Kadoma City Osaka Prefecture F term (reference) 3L060 AA03 CC10 CC19 EE01

Claims (2)

[Claims] An indoor unit is provided with a switch for controlling power supply to an outdoor unit, a control circuit for controlling a load of the outdoor unit to the outdoor unit, and a transformer for supplying power to the control circuit. An air conditioner provided with constant current consuming means for predicting a drive current of the load according to a control state of the load and stabilizing the drive current of the control circuit to a predetermined value or more. 2. The air conditioner according to claim 1, wherein said constant current consuming means comprises a fan motor drive detecting circuit for detecting driving of a fan motor of the outdoor unit, and a constant current consuming circuit.