JPS6191466A - Controller for defrostation operation of air conditioner - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a defrosting operation control device during heating operation of an air conditioner equipped with a frequency converter.

Conventional configuration and its problems Conventionally, the refrigeration cycle of an air conditioner equipped with a variable frequency device during defrosting operation is as shown in Fig. 6. 2, it is condensed in the frosted outdoor heat exchanger a, the pressure is reduced in the pressure reducing device 4, the air passes through the indoor heat exchanger 5, passes through the four-way valve 2 again, returns to the compressor 1, and the indoor and outdoor blower is stopped. Was.

However, conventional air conditioners equipped with frequency converters use high frequency compression to shorten the defrosting time during defrosting operation. Refrigerant was returning to the compressor. For this reason, even though the pressure iZ-cooler was operated at a high frequency, the defrosting time could not be shortened very effectively.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional problems, and aims to dramatically improve the defrosting time of an air conditioner equipped with a frequency converter.

Structure of the Invention In order to achieve this object, the present invention includes a temperature detection means for detecting the temperature t of the outdoor heat exchanger and converting it into an electric signal, and a temperature detection means that detects the temperature t of the outdoor heat exchanger and converts it into an electric signal, and a temperature detection means that detects the temperature t of the outdoor heat exchanger and converts the electric signal of the temperature detection means and the defrosting operation start setting humidity T1.
Comparing means 1 and comparing means 2 are provided for comparing and determining the electrical signal of the defrosting operation end temperature T2 and the electrical signal of the defrosting operation end temperature T2, respectively,
By combining the control signals of the comparison means 1.2, the heating operation mode stored in the storage means and the solenoid valve that stops the indoor/outdoor blower, switches the four-way valve to the refrigeration cycle during cooling operation, and bypasses the pressure reducing device. calculation means for selecting one of the defrosting operation modes for opening the compressor and operating the compressor at a set frequency; and output means for controlling the compressor, four-way valve, seven-legged valve, and indoor/outdoor blower, respectively, based on the signals from the storage means. 1. Output means 2. Output means; 3. Output means 4.

With this configuration, during defrosting operation of an air conditioner equipped with a frequency converter, the pressure of the refrigerant returning to the compressor increases, the amount of circulation increases, and the defrosting time is dramatically improved.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 5 of the accompanying drawings.

In FIG. 1, the control circuit includes a temperature detection circuit 21 including a temperature detection thermistor 9 provided in the outdoor heat exchanger, and a resistance circuit 10 that outputs an electric signal of the defrosting start temperature T1.
, a resistance circuit 11 that outputs an electrical signal of the defrosting end temperature set value T2, a comparator 12 that compares and determines the electrical signal of the temperature detection circuit 21 and the electrical signal of the resistance circuit 10, and the temperature detection circuit 21.
A comparator 13 that compares and determines the electric signal of the resistor circuit 11 with the electric signal of the resistor circuit 11, H output from the comparator 12 and the comparator 13,
A microconbeater 14 (hereinafter referred to as LS114) has a built-in arithmetic circuit that selects either the heating operation mode or the unregistered operation mode and a memory circuit that stores the heating operation mode and the defrosting operation mode according to the combination of control signals of L. ),
The four-way valve is turned on by the electrical signal output from the LS114.
Relay circuit 15 for N/OFF operation, ON/OFF for solenoid valve
Relay circuit 16 that turns off the indoor/outdoor blower
It is equipped with a relay circuit 17 for N/OFF operation, an output circuit 18 with a built-in power transistor for operating the compressor 19 at a set frequency, and a power supply circuit 20 for supplying voltage to the output circuit 18.

Now, to explain the relationship between the block diagram shown in FIG. 2 and the control circuit shown in FIG. 1, the temperature detection circuit 21 shown in FIG.
corresponds to the temperature detection means in FIG. 2, and the resistance circuit 1 in FIG.
01 resistance circuit 11 sets temperature T1 and set temperature T in Fig. 2.
2, respectively, and correspond to comparators 12 and 13 in FIG.
correspond to comparison means 1 and comparison means 2 in FIG. 2, respectively,
The arithmetic circuit and memory circuit built into the LS 114 in FIG. 1 correspond to the arithmetic means and memory means in FIG. 2, respectively, and the relay circuit 15. The relay circuit 16 and the relay circuit 17 correspond to the output means 1, the output means 2, and the output means 3 in FIG.
The output circuit 18 in FIG. 1 corresponds to the output means 4 in FIG. 2.

Next, the configuration and operation of the control circuit consisting of the above configuration are shown in Figure 3~
This will be explained with reference to FIG. In addition, FIG. 4 is a diagram showing a refrigeration cycle in which a solenoid valve 8 that bypasses the pressure reducing device 4 during defrosting is provided in FIG. 6 of the conventional refrigeration cycle. Also the fifth
The figure shows the pressure characteristics over one hour during defrosting.

During heating operation, the electric signal output from the temperature detection circuit 21 provided in the outdoor heat exchanger indicates the defrosting operation start temperature T.
If the electrical signal 1 is also low, a control signal is transmitted from the comparator 12 to the arithmetic circuit built in the LS 114 9, the defrosting operation mode of the memory circuit is selected, the four-way valve relay circuit 15 is turned off, and the air conditioner is cooled. The refrigeration cycle is activated, the relay circuit 16 for the solenoid valve 8 that bypasses the pressure reducing device 4 is turned on, the solenoid valve 8 is opened, the indoor/outside Km relay circuit 17 is turned off, the blower is stopped, and the compressor is operated at the set frequency. The output circuit 18 with a built-in power transistor pivots so that the power transistor 19 operates. After that, the defrosting operation continues until the electric signal output from the temperature detection circuit becomes higher than the electric signal of the defrosting end set temperature T2, and when it becomes higher, the control signal H is output from the comparator 13 and the defrosting operation starts. ends.

The flow of the above operation is shown in the flowchart of FIG. 3, and the refrigeration cycle diagram is shown in FIG.

It is assumed that the time control for entering the unregistered operation during heating operation and the heating operation start control after defrosting are performed in the heating operation mode.

Effects of the Invention As is clear from the above embodiments, the defrosting operation control device for an air conditioner equipped with a frequency converter according to the present invention bypasses the pressure reducing device according to the refrigerant pressure, so that the pressure of the refrigerant returning to the compressor is reduced. As the temperature rises and the circulation amount increases, the defrosting time can be dramatically improved, producing the effect of operating the compressor at a high frequency, and providing an excellent effect of improving the feeling during heating operation.

[Brief explanation of the drawing]

Fig. 1 is a control circuit diagram of a defrosting control device for an air conditioner equipped with a frequency conversion device equipped with a microcomputer, Fig. 2 is a block diagram expressing the control device as a means for realizing functions, and Fig. 3 is the control device. Flowchart showing the operation of 4th
The figure is a diagram of a refrigeration cycle equipped with a solenoid valve, FIG. 5 is a pressure one-hour characteristic graph during defrosting operation, and FIG. 6 is a diagram of a conventional refrigeration cycle. 1... Compressor, 2... Four-way valve, 3...
... Outdoor heat exchanger, 4 ... Pressure reduction device, 5
...Outdoor heat exchanger, 6...Outdoor blower, 7...Indoor blower, 8...Bypass solenoid valve, 9... ...Thermistor, 10.1
1...Resistance circuit, 12.13...Comparator, 14...Microcomputer, 15...
...Relay circuit, 16...Relay circuit, 1
7... Relay circuit, 18... Output circuit, 19... Compressor, 20... Power supply circuit, 21... Temperature detection circuit . Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Figure 4 Figure 5 A1 Figure 6

Claims (1)

[Claims] A refrigeration cycle is composed of a compressor, a four-way valve, an outdoor heat exchanger, a pressure reducing device, an indoor heat exchanger, and an indoor/outdoor blower. After the heating operation starts, the temperature t of the outdoor heat exchanger is detected and an electric signal is sent. Comparing means 1 and Comparing means 2 respectively compare and determine the electric signal of the temperature detecting means with the electric signal of the defrosting operation start temperature T1 and the electric signal of the defrosting operation end temperature T2. is provided, and by a combination of the control signals from the comparison means 1 and 2, the heating operation mode stored in the storage means and the indoor/outdoor blower are stopped, the four-way valve is switched to a refrigeration cycle during cooling operation, and the depressurization is performed. A calculation means for opening a solenoid valve that bypasses the device and selecting one of the defrosting operation modes for operating the compressor at a set frequency; and a signal from the storage means for controlling the compressor, the four-way valve, the solenoid valve, and the indoor/outdoor blower. This is a defrosting operation control device for an air conditioner, which is composed of output means 1, output means 2, output means 3, and output means 4, respectively.