JPH07120050A - Air conditioner - Google Patents

Abstract

PURPOSE:To easily ascertain the condition of a high voltage in a controller by a method wherein a display lamp which is lighted when a DC voltage of a solar battery, which is supplied to an inverter circuit, exceeds a predetermined value, is provided on a substrate for printed circuit. CONSTITUTION:When a switch 26 is closed, a DC voltage, which has been subjected to voltage-doubler-rectification, is supplied to an inverter circuit through a smoothing capacitor 15 and a noise filter 16. Or, after an output of a solar battery 25 is boosted by a converter 7, a DC output is supplied to the inverter circuit. At this time, a display lamp 17 connected to a portion between buses of the DC voltage is lighted to display that the DC voltage is being supplied to the inverter circuit. A resistor 18 is so set that the display lamp 17 is lighted when a high voltage, which is deemed dangerous, remains. When the switch 26 is opened after operation, the DC voltage is continued to be supplied to the inverter circuit during a period until electric charges accumulated in capacitors 13, 14 and the smoothing capacitor 15 are discharged and, at the same time, the lighted condition of the display lamp 17 it maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner, and more particularly to improving safety during maintenance and inspection.

[0002]

2. Description of the Related Art Generally, a conventional control device for such an air conditioner has been disclosed in Japanese Patent Laid-Open No. 56-110859. This publication describes an air conditioner in which a compressor, a condenser, a pressure reducing device, and an evaporator are sequentially connected in an annular shape by refrigerant pipes, and the number of revolutions of the compressor is variable, and a direct current is applied to an inverter circuit. It was supplied to the compressor after being converted to an arbitrary frequency by.

[0003]

In the conventional air conditioner as described above, the compressor was driven by the output of the inverter circuit composed of six NPN type transistors.
Therefore, only the positive voltage is applied to the compressor. That is, in order to drive the compressor with an amplitude alternating current having an effective value of 100 [V], a DC voltage of about 280 [V] is required. In this way, there is a high voltage inside the control device, and even if the power is cut off, the high voltage may be output due to the charging charge of the smoothing capacitor.If maintenance or inspection is performed at this time, there is a risk of exposure to the high voltage. It was something.

In view of such a problem, the present invention provides an air conditioner capable of easily confirming a high voltage state in a control device.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a compressor, a condenser, a pressure reducing device and an evaporator are sequentially connected in an annular shape by a refrigerant pipe to form a refrigeration cycle, and an output from an inverter circuit is used. In an air conditioner in which the number of revolutions of a compressor is determined, a solar battery power supply unit that supplies DC power to an inverter circuit, a printed circuit board equipped with a control unit that controls the operation of the inverter circuit, and a printed circuit board And is turned on when the DC power output from the solar cell power supply unit is equal to or more than a predetermined value.

[0006]

According to the present invention constructed as described above, the indicator lamp provided on the printed circuit board is lit while the inside of the control device is in the high voltage state.

[0007]

Embodiments of the present invention will now be described with reference to the drawings, in which 1 is a compressor, and a condenser 2, a decompression device 3 and an evaporator 4 are sequentially connected in an annular shape by refrigerant pipes to form a refrigeration cycle. I am configuring. Incidentally, 5 is a blower fan of the condenser 2, and 6 is a blower fan of the evaporator 4. Reference numeral 7 denotes a printed circuit board in the control device, on which the diodes 9 to 12 for rectifying the alternating current from the alternating current power source 8 having a rating of 100 [V] (power source section), the capacitors 13 and 14, and the smoothing. A capacitor 15, a noise filter 16, an indicator lamp 17, a resistor 18, six NPN transistors 19 to 24 forming an inverter circuit, a controller 25, etc. are mounted. The control unit 25 supplies a switching signal based on the PWM system to the transistors 19 to 24 of the inverter circuit. At the same time, the operation of the blower fans 5 and 6 is also controlled. Further, reference numeral 26 is a power switch for cutting off or connecting the AC power supply. The control unit 25 operates by turning on this switch.

Reference numeral 26 is a solar cell which outputs a DC output through a converter 27. The converter 27 keeps the output voltage of the solar cell 26, which changes depending on the amount of solar radiation, at DC
The voltage is increased so as to maintain 80 [V].

The output of the solar cell is weak and the direct current is 280
When the voltage cannot be raised to [V], the changeover switch 28 is automatically changed over to the AC power source 8 side.

The changeover switch 28 connects either the direct current from the AC power source 8 side or the output from the solar cell 26 side to the inverter circuit side. As the changeover switch 28, one that can be manually operated is used. The state shown in FIG. 1 is a state in which the changeover switch 28 is connected to the solar cell 26 side.

In the air conditioner configured as described above, when the switch 26 is turned on, the DC voltage doubled and rectified is sent to the inverter circuit through the smoothing capacitor 15 and the noise filter (or active filter) 16. Supplied.

Alternatively, the output of the solar cell 26 is converted into the converter 2
The DC output after being boosted by 7 is supplied to the inverter circuit. At this time, the indicator lamp (L
ED) 17 lights up to indicate that the DC voltage is being supplied to the inverter circuit. The indicator lamp (LED) 17 is set with a resistor 18 so as to light up when a dangerous high voltage remains. For example, the resistor 18 is set so that a current of about 10 mA flows through the indicator lamp (LED) 17 at a direct current of 280 [V]. The resistance value is set appropriately according to the indicator light (LED) used. At this time, the control unit 25
Transistors 19 to 24 are turned on by the switching signal of
-OFF and output the desired frequency to the compressor.

After such an operation, if the operation switch 26 is opened, the capacitors 13, 14 and the smoothing capacitor 15 are opened.
The DC voltage remains supplied to the inverter circuit until the electric charges accumulated in the indicator lamp 1 are discharged.
7 keeps the lighting state. After that, when the charge of the capacitor is discharged, the light emitting element 17 is also turned off. Therefore, it is possible to confirm whether or not there is a high voltage in the control device by turning on or off the light emitting element 17.

In the above embodiment, the high voltage part such as the inverter circuit is mounted on the blind substrate 7, but this may be a separate substrate or a separate component. Also,
The mounting position of the indicator lamp 17 is not limited to the above-described embodiment, but may be provided at a position where the operating state of the power supply unit by double voltage rectification can be detected.

Further, if the filter 16 is used as an active filter and both the output from the AC power supply 8 and the output from the solar cell 26 are supplied to the inverter circuit without using the changeover switch 28, the active filter is obtained. By this function, when the output from the solar cell 26 is insufficient, the shortage can be supplemented from the AC power supply 8, and when the output of the solar cell is large, surplus power can be sent to the AC power supply 8 side.

[0016]

The present invention provides a compressor, a condenser, a pressure reducing device,
In an air conditioner in which an evaporator is sequentially connected in a ring by refrigerant pipes to form a refrigeration cycle, and the number of revolutions of the compressor is determined by the output from the inverter circuit, a solar power supply that supplies DC power to the inverter circuit. A battery power supply unit, a printed circuit board on which a control unit for controlling the operation of the inverter circuit is mounted, a display provided on the printed circuit board, and the DC power output from the solar battery power supply unit is turned on at a predetermined value or more. Since the lamp is provided, the indicator lamp can be turned on and displayed while the DC voltage is supplied from either the AC power source or the solar cell. Therefore, when performing maintenance and inspection of the control device, if the indicator light on the printed circuit board is lit, turn off the power and confirm that the indicator light is off, then perform maintenance,
If the inspection work is performed, the work can be performed safely without being exposed to the danger of high voltage.

Further, it is possible to judge whether or not the solar cell is generating power by turning on the indicator light, and it can be used as a measure for switching the solar cell.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram showing an embodiment of the present invention.

[Explanation of symbols]

 17 indicator light 26 solar cell 27 converter 28 changeover switch

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masaki Koji Masaki Korihan 2-5-5, Moriguchi City, Osaka Prefecture Sanyo Electric Co., Ltd. (72) Hisashi Tokizaki 2 Keihanmoto Street, Moriguchi City, Osaka Prefecture 5-5, Sanyo Electric Co., Ltd.

Claims (1)

[Claims] 1. An air conditioner in which a compressor, a condenser, a decompression device, and an evaporator are sequentially connected in an annular shape by a refrigerant pipe to form a refrigeration cycle, and a rotation speed of the compressor is determined by an output from an inverter circuit. In the machine, a solar battery power supply unit for supplying DC power to the inverter circuit, a printed circuit board equipped with a control unit for controlling the operation of the inverter circuit, and the solar battery power supply unit provided on the printed circuit board. A controller for an air conditioner, comprising: an indicator lamp that lights up at a predetermined value of DC power output from the controller.