JPS60259869A - Defrostation controller for heat pump type 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 control device for a heat pump type air conditioner.

Configuration of conventional example and its problems In the conventional defrosting control device of a heat pump air conditioner, the cumulative operating time of the compressor during heating operation is 60 minutes, and
When the outdoor heat exchanger temperature reaches the defrosting start temperature, a defrosting signal is issued and defrosting operation is performed, and the cumulative time of defrosting operation is 1o.
When the temperature of the outdoor coil reaches the defrosting end temperature, the defrosting operation is ended and the heating operation is resumed, which is repeated at intervals. For this reason, the defrosting operation
If the defrosting ends after an integrated time of 10 minutes, there is a high possibility that frost residue will occur, which means that the operation efficiency of the next heating operation will be poor, and there is a high possibility that frost residue will occur again when defrosting is finished next time. It had the following drawback.

Purpose of the Invention Therefore, the present invention provides that, if frost remains at the end of the defrosting operation, the operating frequency of the compressor is increased during the next defrosting operation to increase the defrosting ability and prevent the defrosting from ending. The purpose is to prevent boxes from being left behind at times.

Structure of the Invention In order to achieve this object, the present invention aims to reduce the temperature of the outdoor coil when the defrosting operation is terminated when the accumulated time of the defrosting operation reaches a certain value, since there is a high possibility that residual frost will occur. The compressor operating frequency is set to be higher during the next defrosting operation than when the defrosting operation was ended when the defrosting end temperature was reached.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a diagram of a refrigeration system of an air conditioner according to an embodiment of the present invention, where 1 is an indoor unit and 2 is an outdoor unit. 3 is a compressor, 4 is an outdoor coil, 6 is a four-way valve, 6
Reference numeral numeral 1 indicates a reducing device, and 7 indicates an indoor coil, which are connected in a ring to form a refrigeration cycle. Reference numeral 8 denotes an indoor fan that circulates air in the air-conditioned space and exchanges heat with the indoor coil 7. Reference numeral 9 denotes an outdoor fan that exchanges heat with outside air and the outdoor coil 4.

FIG. 2 is a circuit block diagram in one embodiment of the present invention. Reference numeral 10 denotes a control section, which uses a microcomputer (hereinafter referred to as microcomputer) in this embodiment. 11
12 is a room temperature sensor for detecting the indoor temperature, and 12 is a room temperature setting device for setting a target value of the room temperature. A 13-digit comparator compares the detected value of the room temperature sensor 11 with the set value of the room temperature setter 12, and as shown in the thermo chart of FIG. 0 to 1.0℃
．． It is divided into 7 zones, divided into 5°C increments.

The microcomputer 10 then associates a set frequency with each zone. Reference numeral 14 denotes a remote control which outputs signals such as operation modes such as operation/stop and cooling/heating/air blowing to the microcomputer 10. 15 is a temperature sensor attached to the outdoor coil 4 and detects the outdoor coil temperature; 16 is a setting unit for setting the defrosting start temperature and defrosting end temperature of the outdoor coil 4. However, there is a temperature differential between the defrosting start temperature and the defrosting end temperature. 17 is a judge,
The detected value of the temperature sensor 15 and the setting value of the setting unit 16 are compared, and when the outdoor coil temperature is lower than the defrosting start temperature, a signal of 1° is output, and when it is higher than the defrosting end temperature, a signal of 0 is output. A signal is output to the microcomputer 1o. 18 is a first relay that controls the operation/stop of the indoor fan 8, 19 is a second relay that controls the operation/stop of the outdoor fan 7, and 20 is a system The third relay controls the opening and closing of a four-way valve that switches to cooling/heating and defrosting operation by switching the refrigerant flow path of the refrigerant, and is controlled by the microcomputer 10. 21 is an AC power supply, and 22 is an AC power supply. 21 is a rectifier circuit that converts 21 to DC. 23id Frequency conversion bag 6 that converts DC to AC Seven.

45 Hz, 55 Hz, 65 Hz, 7
5 Hz. Thereby, the compressor motor 24 is variably increased in the range of 1500 to 4500 r, p, m.

FIG. 4 is a flowchart of the microcomputer 1o, and the operation mode is heating operation. As an initial setting, a first timer for accumulating the operating time of the compressor motor 24 and a second timer for accumulating the defrosting operating time are set to 60 minutes and 10 minutes, respectively, and the defrosting operating frequency is set to 65 Hz. ing. Next, after turning on the indoor fan 8, the output from the comparator 13 is taken in, and if the zone is A-F, the set frequency corresponding to each zone is output to the frequency converter 23, and the The outdoor fan 7 and the four-way valve 5 are turned on, and the integration of the first timer is started. Next, it is determined whether the @-th timer has accumulated 60 minutes, and if it has not accumulated, it returns to 1. The comparator 1
If the output of 3 is in the G zone, the integration of the first timer is stopped, the compressor motor 24 and the outdoor fan 7 are turned off, and the process returns to 1. The first timer is 6Q
If the second timer is integrated, the output from the determiner 17 is taken in, and if II is 11+, the first timer is reset;
The integration of the second timer is started, the defrosting frequency initially set to 65 is output to the frequency converter 23, and the indoor/outdoor fans 8, 7 and the four-way valve 5 are set to 0F.
Start FL defrosting operation. Next, the second timer is set to 10
Determine whether the minutes have been accumulated, and if not, return to step 2. If the output of the determiner 17 is "°○'", the defrosting operation is ended, the second timer is reset, the defrosting frequency is set to 66, and the heating operation is resumed. If the output is °°1"', defrost operation is continued.

When the second timer has accumulated 10 minutes, the defrosting operation is ended, the timer is reset, the defrosting frequency is set to 75, and the heating operation is resumed. In this case, the operating frequency during the next defrosting operation will be 75 Hz. Therefore, when the defrosting operation ends when the second timer completes the 10-minute integration, the outdoor coil temperature will reach the defrosting end temperature. Therefore, there is a high possibility that frost residue will occur and the defrosting capacity is insufficient.The next defrosting operation will be performed by increasing the operating frequency from 6517 to 7582. Prevents frost residue from forming at the end II
-Can be done.

Effects of the Invention As is clear from the above explanation, the present invention is advantageous in that when the defrosting operation is finished due to the accumulated time of the defrosting operation reaching a certain value, there is a high possibility that residual frost will occur. Since the compressor operating frequency for the next defrosting operation is set higher than when the defrosting operation ended when the coil temperature reached the defrosting end temperature, there will be no residual frost at the end of the defrosting operation. This has the effect of preventing this from occurring.

[Brief explanation of drawings]

Fig. 1 is a refrigeration system diagram showing one embodiment of the present invention;
The figure is the circuit block diagram, Figure 3 is the thermo chart diagram,
FIG. 4 is a flowchart 1 diagram. 9. 3...Compressor, 5...Four-way valve, 4...
・Outdoor coil, 6... pressure reducer, 7...
Indoor coil, 10...Control unit, 23...
Frequency conversion device, 15...Temperature sensor, 17.
...Judgment device. Name of agent: Patent attorney Toshio Nakao and 1 other person Atsushi 1
Figure 2 Figure 3

Claims (1)

[Claims] A refrigeration cycle consisting of a compressor, a four-way valve, an outdoor coil, a pressure reducer, an indoor coil, etc., a frequency converter that varies the operating frequency of the compressor, and a temperature sensor that detects the temperature of the outdoor coil. a determination device for determining whether a value detected by the temperature sensor is a defrosting start temperature of the outdoor coil or a defrosting end temperature; When the determining device determines that the outdoor coil defrosting start temperature is reached, a defrosting operation is performed in which the output frequency of the frequency converter can be arbitrarily set, and whether the integrated defrosting operation time reaches a certain value, Alternatively, the control unit includes a control unit that returns to heating operation when the determination device determines that the outdoor coil defrost end temperature is reached, and the control unit controls the defrosting operation when the cumulative defrosting operation time reaches a certain value. When the operation is completed, the determination device determines that the outdoor coil defrost end temperature is reached, so that the compressor's temperature during the next defrost operation is lower than when the defrost operation is completed. A defrosting control device for a heat pump air conditioner that sets an operating frequency to a higher value using the frequency converter.