JPS6029535A - Control circuit of air conditioner - Google Patents

Abstract

PURPOSE:To securely prevent the deterioration of the reliability or troubles of an air conditioning device by a method wherein the device is made to shift automatically to the normal operation after elapsing the determined compulsory operation time. CONSTITUTION:A room temperature sensor 13, which detects the room temperature and outputs a signal complying with this temperature, a room temperature setting instrument, which sets the room temperature and outputs a signal complying with this temperature, a controlling device 12, which acquires the deviation value between the defected signal of the sensor 13 and the setting signal of the room temperature setting instrument and drives the compressor basing on this deviation value, and a switch 14 for a compulsory operation, which compulsory conducts a cooling operation or warming operation by short-circuiting or opening the sensor 13, are provided. Furthermore, a timer 40 is put in complying with the switch 14, and the function of the switch 14 is recovered after determined time, and the air conditioning device is shifted to the normal cooling operation or warming operation. Herewith, the deterioration of the reliability or troubles etc. of the air conditioning device owing to the long duration of the compulsory operation is securely prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a control circuit for an air conditioner having a forced operation switch that forcibly performs cooling or heating operation.

[Technical background of the invention]

FIG. 1 is a schematic diagram of a conventional striped air conditioner. In the figure, 1 is an indoor unit, 2 is an outdoor unit, and these are electrically connected to each other via a terminal board 3. The indoor unit 1 has a power switch 10
, a power transformer 11 , and a control device 1 to which a control voltage is applied via the power switch 10 and the power transformer 11
2, an indoor sensor 13 composed of a resistor or the like having negative temperature characteristics, which detects the indoor temperature and provides a detection signal thereof to the control device 12; and an indoor sensor 13 that is connected to the room temperature sensor 13 and short-circuits or opens the room temperature sensor 13. A forced operation switch 14;
A heat exchange sensor 15 that detects the temperature of an indoor heat exchanger (not shown) and sends a detection signal to the control device 12, and various functions such as starting and stopping operation, switching between cooling and heating, setting indoor temperature, and setting air volume. A remote controller (hereinafter referred to as "remote control") 16 that gives a command signal to the control device 12, and an indoor fan 17 that is driven at a predetermined rotation speed based on the control signal given from the control device 2. . Here, the controller [12 is
A fuse installed between the power switch 10 and the power transformer 11 to prevent short-circuit accidents, a varistor 21 and a line filter n to prevent noise from entering, and the power transformer 1
A rectifier (not shown) that rectifies the AC voltage given from 1 to DC to create a control voltage, and the deviation between the room temperature setting signal from the remote controller 16 and the room temperature detection signal from the room temperature sensor 13.
A microprocessor that controls the indoor fan 17, whose rotation speed is varied in multiple steps such as strong wind, weak wind, and breeze, to the optimum rotation speed based on the deviation amount of the eye, the temperature detection signal from the heat exchange sensor 15, etc. (not shown), and a relay contactor that is connected in series between the power switch 10 and the terminal board 2 and is turned on based on an operation start command from the remote controller 6 to supply AC power to the outdoor unit 2 via the terminal board 3. It is equipped with On the other hand, the outdoor unit includes a control device I mainly based on a microprocessor, a heat exchange sensor 31 that detects the temperature of an outdoor heat exchanger (not shown), an outdoor fan 32, a rectifier circuit, an inverter 34, a compressor 35, etc. and is connected to the indoor unit 1 via a terminal plate 36.

In addition, the outdoor unit 2 includes a four-way valve 37 for switching between air conditioning and heating.
A reactor for suppressing the current when starting the compressor, a capacitor 39 for operating the outdoor fan, etc. are also installed.

In the above configuration, when the power switch 10 is turned on and an operation start command signal is given from the remote control 16 to the control device 12, power is supplied to the indoor unit 1, and the relay contact n is turned on to power the outdoor unit 2. Supply is made. Then, the microprocessor in the control device 12 inputs the room temperature setting signal given from the remote controller 16 and the room temperature detection signal given from the room temperature sensor 13, calculates the difference between the two, and determines the rotation speed of the indoor fan 17 according to the magnitude of the load. is calculated and the indoor fan 17 is driven at the optimum rotation speed. on the other hand,
The difference signal between the room temperature detection signal and the room temperature setting signal is sent to the terminal end 3.
36 to the control device (materials) of the outdoor unit 2. Then, the control device side calculates the rotation speed of the compressor according to the magnitude of the load based on the difference signal and provides a frequency setting signal to the inverter. This inverter 34
Since the main circuit of the inverter is supplied with DC power rectified by the rectifier circuit, the inverter is turned on by the frequency setting signal.

It is turned off and the compressor is driven at a frequency according to the air conditioning load. This controls the indoor temperature to the set temperature (so-called thermo control operation).

If you want to force the air conditioner to perform cooling or heating operation after a trial run of the air conditioner or when recovering refrigerant gas circulating through the compressor, etc., operate the forced operation switch 14. In the case of cooling operation, the room temperature sensor 13 is short-circuited, and in the case of heating operation, the room temperature sensor 13 is opened. Since the room temperature sensor 13 is composed of, for example, a resistor having negative temperature characteristics, the resistance value decreases as the temperature rises. Therefore, when the room temperature sensor 13 is short-circuited for cooling operation by the forced operation switch 14, the microprocessor in the control device 12 determines that the resistance is zero, that is, the room temperature is high, and gives an operation command signal to the compressor A. The compressor A is driven. Similarly, when the room temperature sensor 13 is opened for heating operation by the switch 14, the control device 12 determines that the resistance is infinite, that is, the room temperature is low, and drives the compressor A.

This allows forced operation to be performed simply and accurately.

[Problems with background technology]

However, in the conventional control circuit, the forced operation switch 14 short-circuits or opens the room temperature sensor 13, so as long as the switch 14 is turned on to the cooling or heating side, the air conditioner continues forced cooling or heating operation.

Therefore, if the forced operation lasts longer than necessary, such as by neglecting to return the switch 14 to its original position (normal operating state position) and turn on the room temperature sensor 13 again, the air conditioning load may fluctuate during that time. This has the drawback of not being able to deal with this problem, leading to failures and deterioration of reliability of the air conditioner.

[Purpose of the invention]

The present invention was made in order to eliminate the drawbacks of the prior art as described above, and after a predetermined forced operation time has elapsed, normal operation (so-called thermo control operation) is automatically started.
The purpose of the present invention is to provide a control circuit for an air conditioner that is reliable and easy to use in actual use.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention is turned on in response to a forced operation switch that short-circuits or opens a room temperature sensor to forcibly perform cooling operation or heating operation, and after a predetermined time elapses, the forced operation switch is turned on. A timer is provided to restore the function.

[Embodiments of the invention]

An embodiment of the present invention will be described below based on the accompanying drawings.

In the following drawings, the same elements as in FIG. 1 are given the same reference numerals.

FIG. 2 shows a schematic diagram of the main parts of the control circuit according to this embodiment. This control circuit differs from the one shown in FIG. 1 in that a timer is provided on the indoor unit 1 side, and the forced operation switch 14 is returned to its original position after a predetermined period of time.

That is, in this embodiment, the timer body 40 is connected between one end of the fuse and one end of the relay contact B, and a series closed loop of the power switch 10 - the relay contact B - the timer body 40 - the fuse and the power switch 10 is formed. form. Furthermore, the relay body 40 turns on after the set time has elapsed.
Two timer contacts 401 and 40□ that turn off are provided between the room temperature sensor 13 and the forced operation switch 14. here,
The structure of the switch 14 includes, for example, four terminals 14a,
14b, 14o, and 14d, when the switch is in the cooling operation position, the terminals 14IL and 146 are connected, and when the switch is in the heating operation position, the terminals 14c and 14d are connected,
Furthermore, when the normal operating position is set, the terminals 14 and 144 are connected. and terminal 14. is connected to the microprocessor between the control devices, while terminal 14a is connected to timer contact 4.
0. The terminal 14b is connected to the room temperature sensor 13 via the
The terminals 14c are each connected to a microprocessor in the control device 12 via timer contacts 40□. Therefore, when the forced operation switch 14 is set to the normal operation position, the room temperature sensor 3 is connected to the control device 12, and when it is set to the cooling operation position, the normally closed side 40 of the timer contact 40, b - terminal 14a.
One terminal14. The room temperature sensor 3 is short-circuited in this loop, and when the heating operation position is set, the normally closed side 40 of the timer contact 40□
□, the room temperature sensor 3 is released in a loop of one terminal 14c and one terminal 14a. The forced operation switch 14 may have a structure other than that shown in FIG. 2 as long as it has the above function.

In the above configuration, when the forced operation switch 14 is set to the cooling operation position and the power switch 10 and relay contacts are turned on to start forced operation, the timer main body 40 is energized and one side is turned off during the timer set time. Timer contact 40
is connected to the normally closed side 401b, and the other current contact 40□ is connected to the normally closed side 40□5.

Therefore, the room temperature sensor 3 is short-circuited during the time set by the timer, and cooling operation is forcibly performed during this time.

When the set time of the timer has elapsed, the timer contact 40
□, 40□ are switched to the normally open side, and the room temperature sensor 13 is connected to the control device 12 in a loop of room temperature sensor 3 - timer contact normally open side 40□8 - terminal 14c - terminal 14d, and normal operation is started. and enters thermo control operation state. Similarly, when the forced operation switch 14 is set to the heating operation position and forced operation is started, the room temperature sensor 13 is open during the timer setting time, but after the timer setting time has elapsed, the timer contacts 401 and 402 switch to the normally open side 40. The mode is switched to □1, 40□1, the room temperature sensor 13 is turned on, and the thermo control operation state is entered. In this way, forced operation does not require a very long time, so by performing forced operation for only a very short timer setting time and then shifting to normal thermal condenser operation, the control device 12 and 30 can be Preservation functions such as the console heating prevention function and the indoor heat exchanger anti-freezing function that are pre-programmed in the microprocessor can be used as is, making it easy to prevent adverse effects such as deterioration of reliability and failure of the air conditioner. . In addition, excessive cooling or heating operation can be prevented, so there is no need to worry about getting too cold or too warm.

In FIG. 2, the timer 40 for restoring the function of the forced operation switch 40 after a set time is provided in the control device 12 separately from the microprocessor, but it is also possible to provide a similar timer function in the microprocessor itself. You may also be allowed to have one.

In addition, in FIG. 2, after the timer setting time has elapsed, the control device 1
An example has been shown in which thermal control operation is performed using the room temperature set temperature given externally to the microprocessor in the controller 12 using the remote controller 16, etc.;
, 30 may be programmed to perform thermal control operation in accordance with the programmed set temperature. When such a system is adopted, for example, if the remote control 16 is a so-called wireless system, even if the power supply battery runs out and the remote control 16 stops operating, the control devices 12 and 30 will continue to operate according to the predetermined set temperature. Since the minimum necessary functions such as thermal control operation are maintained and operation continues, usability is greatly improved.

[Effects of the Invention] As explained above, since a timer is provided to restore the function of the forced operation switch after the set time, when the forced operation switch is forced to perform cooling or heating operation, the function of the forced operation switch is reset after the set time. This forced operation automatically shifts to normal cooling or heating operation, and therefore it is possible to easily and accurately prevent deterioration in reliability and failure of the air conditioner due to continued forced operation for a long time.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a control circuit of a conventional air conditioner, and FIG. 2 is a schematic configuration diagram of main parts of a control circuit of an air conditioner according to an embodiment of the present invention. 1...indoor unit, 2...outdoor unit), 12.
30...Control device, 13...Room temperature sensor, 14...
・Forced operation switch, 15...Heat exchange sensor, 16.
...Remote controller, 17...Indoor fan, 32...Outdoor fan, 33...Rectifier circuit, 34...Inverter,
Ah...compressor, 4o...timer body, 401
, 40□...Timer contact. Applicant's agent Kiyoshi Inomata

Claims (1)

[Claims] A room temperature sensor that detects the indoor temperature and outputs a signal corresponding to it, a room temperature setting device that sets the indoor temperature and outputs a signal corresponding to it, and a room temperature setting device that detects the amount of deviation between the detection signal of the room temperature sensor and the setting signal of the room temperature setting device. An air conditioner comprising: a control device that drives a compressor and an indoor fan based on the deviation amount of the mesh; and a forced operation switch that shorts or opens the room temperature sensor to forcibly perform cooling operation or heating operation. An air conditioner characterized in that the control circuit of the device is provided with a timer that is turned on in response to the forced operation switch and returns the function of the forced operation switch after a predetermined period of time to shift to normal cooling or heating operation. Control circuit for the harmonizer.