JPH0229943B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a control device that can automatically select heating and cooling operation of an air conditioner.

Conventional configurations and their problems In air conditioners capable of cooling and heating, in order to save the user the trouble of operating the cooling or heating switch, the
There is a control device that automatically selects cooling operation or heating operation, and with the spread of microcomputers in recent years, the number of air conditioners that have such an automatic heating and cooling switching control device is increasing.

This type of automatic air conditioning/heating switching control device detects the indoor temperature using a temperature sensor that detects the indoor temperature, and starts cooling operation if the temperature is above a preset temperature, and heating mode if the temperature is below a preset temperature. .

By the way, in many cases, the temperature sensor is installed on the suction side of the heat exchanger, so if the air conditioner was running immediately before the automatic cooling/heating judgment, the heat exchanger would have been cooled if it was cooling. Temperature sensors sensed low temperatures due to radiation, etc., and heated the room when it should have been cooled. There were also cases where the opposite was true, where the air conditioner was turned on when it should have been heated. This problem also occurs when determining whether to use air conditioning or heating based on outdoor temperature. Alternatively, in winter, when a kerosene heater is used, warm air accumulates near the ceiling due to convection, and the temperature sensor detects this warm air and starts cooling operation even in winter. .

Therefore, conventional automatic air conditioning/heating switching control devices force only the fan involved in indoor or outdoor temperature detection to operate immediately before deciding whether to cool or heat the room, and this allows the temperature sensor to detect accurate room temperature or It was sensing the outside temperature.

However, when the temperature is extremely low, such as in the winter, forcing only the indoor fan to run will cause the room to be very cold, and no matter whether you force the indoor or outdoor blower to run,
There was a problem that the start of operation of the compressor was delayed and it took extra time for the room temperature to rise.

OBJECTS OF THE INVENTION The present invention is intended to solve the above-mentioned conventional problems, and aims to eliminate the delay in room temperature rise and the feeling of cold air during the winter season, etc., for determining heating and cooling in an automatic heating and cooling switching device.

Structure of the Invention In order to achieve this object, the present invention includes a temperature detection means for detecting an indoor temperature or an outdoor temperature T _A at an indoor or outdoor heat exchanger suction port and converting it into an electric signal, and an electric signal of the temperature detection means. A comparison means A compares the electric signal of the cooling operation set value T _C and outputs two control signals of HL, and compares the electric signal of the temperature T _A and the electric signal of the immediate operation set value T _S and outputs H and L. a comparison means C that outputs two control signals; a comparison means B that compares the electric signal of the temperature T _A and the electric signal of the heating operation setting value T _H and outputs two control signals H and L;
A timing means for timing the indoor or outdoor blower operating time after shifting to the automatic cooling/heating determination mode, a transition means A for outputting an electric signal for immediately shifting to the heating operation based on the output of the comparison means C, and the timing means. When an electric signal is output after a set time t _s has elapsed, a transition means B outputs an electric signal for transitioning to cooling or heating operation according to the outputs of the comparison means A and B, and the operation mode of cooling or heating operation is stored. The operation of the air conditioner is controlled by an output means that drives a compressor, a blower, a four-way valve, etc. using the electric signals output from the storage means and the electric signals from the transfer means A and B.

This configuration greatly eliminates the delay in room temperature rise during winter when the automatic heating and cooling switching device makes a heating/cooling judgment, and the feeling of cold wind.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1, 2, and 3 of the accompanying drawings.

In FIG. 1, the control circuit includes an AC power supply 1, a body switch 2, a transformer 3, a rectifier circuit 4, and a capacitor 5. (referred to as LSI) 6, timer control circuit 7 that controls the internal timer circuit of LSI 6, operation input switch 8, indoor blower output circuit 9, compressor output circuit 1
0, four-way valve output circuit 14, thermistor 11 that senses indoor temperature T _A , comparison circuit A12 that compares indoor temperature T _A and cooling operation set value T _C , compares indoor temperature T _A and heating operation set value T _H Comparison circuit B13 and comparison circuit C that compares T _A and immediate operation set value T _S
It is equipped with 15.

Here, to explain the relationship between the block diagram shown in FIG. 2 and the control circuit shown in FIG. 1, the thermistor 11 shown in FIG. 1 corresponds to the temperature detection means shown in FIG. Circuit A12, B13
and C15 are comparison means A, B and C of FIG. 2, respectively.
Furthermore, the LSI 6 in FIG. 1 corresponds to the time measurement means, transition means A, B, and storage means in FIG. 2, and the output circuits 9, 10, and 14 in FIG. 1 correspond to the output means in FIG. do.

Next, the operation of the control circuit having the above configuration will be explained with reference to FIG.

In the mode in which automatic cooling/heating judgment is performed at a preset timing, when the automatic judgment timing comes, if the output from the comparator circuit C15 is L, the LSI6 immediately shifts to the heating operation mode, and if the output is H, from that point on, the LSI6 will switch to the external heating operation mode. The LSI 6 inputs the output from the timer 7 and counts a preset time _ts , and at the same time, the LSI 6 forcibly operates the indoor blower using the indoor blower output circuit 9. Meanwhile, the indoor temperature
If T _A is higher than the cooling operation set value T _S , comparison circuit A
The output from comparison circuit B12 becomes H, and if T _A is lower than the heating operation setting temperature T _H , the output from comparison circuit B13 becomes L. When the timer function of LSI6 counts the set time _ts , LSI6 enters the cooling operation mode if the input from comparison circuit A12 is H, and the comparison circuit B
If the input from 13 is L, the mode shifts to the heating mode, and if neither of these conditions apply, the mode shifts to the air blowing mode or the dehumidifying mode depending on the preset mode.

Indoor blower forced operation time t _s is the time when indoor air is forcibly applied to the thermistor 11 when the thermistor 11, which is supposed to sense the indoor temperature, is sensing a false temperature due to heat exchanger radiation or poor temperature distribution. The time required to bring the thermistor temperature close to the room temperature correctly can be selected based on TS.If the heat exchanger is being cooled, the instantaneous operation setting value T _S is the heating operation setting based on the maximum drop in temperature sensor temperature due to the effect of cooling the heat exchanger. It is sufficient to choose a value less than or equal to the value subtracted from the value T _H. These values are determined by the heat capacity and mounting position of the thermistor heat sensitive part.

Further, in the embodiment, a case has been described in which the indoor temperature is used as a reference for the cooling/heating determination, but it goes without saying that similar control is achieved when the outdoor temperature is used as the reference.

Effects of the Invention As is clear from the above embodiments, the automatic heating/cooling switching device for an air conditioner according to the present invention immediately shifts to heating operation if the temperature is below a certain level when automatically determining heating/cooling, and if the temperature is above a certain level, switches off the blower before determining the transition. This system is forced to operate, and compared to conventional systems in which the blower is forced to operate uniformly, it has the effect of eliminating the feeling of cold air at low temperatures and allowing the room temperature to rise more quickly.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an operation control device equipped with a microcomputer, FIG. 2 is a block diagram expressing the function implementation means of the control device, and FIG. 3 is a flowchart of the control device. 1... AC power supply, 2... Equipment switch, 3...
Transformer, 4... Rectifier circuit, 5... Capacitor, 6
...Microcomputer (LSI), 7...Timer control circuit, 8...Operation input switch, 9...
Indoor blower output circuit, 10... Compressor output circuit,
11... Thermistor, 12... Comparison circuit A, 13
... Comparison circuit B, 14 ... Four-way valve output circuit, 15
... Comparison circuit C.

Claims (1)

[Claims] 1 Temperature detection means for detecting the indoor temperature on the suction side of the indoor heat exchanger or detecting the outdoor temperature on the suction side of the outdoor heat exchanger and converting the detected temperature T _A into an electrical signal; Compare the electric signal of T _A and the electric signal of cooling operation setting value T _C to determine 2 of HL.
Comparing means A for outputting a control signal and the temperature T _A
Comparing means B compares the electric signal of the temperature T _{A with the electric signal of the heating operation set value T H} and outputs two control signals H and L, and the electric signal of the temperature T _A and the electric signal of the immediate operation set value T _S Comparison means C outputs two control signals H and L based on the comparison, and measures the indoor or outdoor blower operating time after the timing of automatic cooling/heating judgment set in advance in the automatic heating/cooling switching mode is reached. a timer; a transition means A that outputs an electric signal to immediately shift to heating operation according to the output of the comparison means C; and when the timer outputs an electric signal indicating that a set time t _s has elapsed, the comparison means A; A transition means B outputs an electric signal for transitioning to cooling or heating operation according to the output of B, a storage means that stores the operation mode of cooling or heating operation, and an output from the storage means according to the electric signals of the transition means A and B. An automatic air conditioning/heating switching control device for an air conditioner, which is comprised of an output means that drives a compressor, blower, four-way valve, etc. using the electrical signal generated.