JPS6246151A - Air-conditioning machine - Google Patents

Abstract

PURPOSE:To prevent reduction of room temperature during defrosting operation by a method wherein a defrosting control device, inputting the detecting signals of a defrosting condition detector for an outdoor heat exchanger and a room temperature detector and rising a set room temperature before starting defrosting operation, is provided. CONSTITUTION:The defrosting control device 16 and the room temperature detector 17 are provided in the constitution of a circuit. The defrosting control device 16 is equipped with input terminals IN1, IN2 and an output terminal OUT1 and the detecting signal of the defrosting condition detector 10 is inputted into the input terminal IN1. The detecting signal of the room temperature detector 17 is inputted into the input terminal IN2. The defrosting control device 16 is a micro-computer generally and is provided therein with a program, data and an operating unit. The set room temperature is risen by the defrosting control device 16 by the detecting signals of the defrosting condition detector 10 and the room temperature detector 17 to restrain the reduction of room temperature during defrosting operation. According to this method, the reduction of room temperature during defrosting operation may be prevented without complicating the device.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an air conditioner that defrosts frost adhering to an outdoor heat exchanger during heating operation.

[Conventional technology]

Figures 6 and 7 are for example Utility Model Application No. 57-490393
They are a refrigerant circuit diagram of a conventional heat pump type air conditioner shown as a conventional example in the publication, and an electrical control circuit diagram during defrosting. Of these two figures, first, in Fig. 6, 1 is a compressor;
2 is a four-way valve, 3 is an indoor heat exchanger, 4 is a pressure reducing device, and 5 is an indoor heat exchanger. These compressor 1, four-way valve 2,
The indoor heat exchanger 3, the pressure reducing device 4, and the outdoor heat exchanger 5 are connected in an annular manner by a refrigerant pipe 6, and the refrigerant is passed through the refrigerant circuit I.
I! It constitutes I7. Further, an indoor fan 8 is arranged opposite to the indoor heat exchanger 3, and an outdoor fan 9 is also arranged in the outdoor heat exchanger 5. A defrosting condition detector 10 whose temperature sensing portion is in contact with the inlet pipe of the outdoor heat exchanger M5 is disposed. Defrost condition detector 1
0 outputs a detection signal, contacts 11a and llb of the switching contact 11 shown in FIG. 7 are switched. The contact 11a of this switching contact 11 is normally closed,
When the defrosting condition detector 10 outputs a detection signal, the contact 11
It is designed to close b. The contact 11a is connected to one of the control power terminals 15 via the drive coil 2a of the four-way valve 2 and one contact of the heating switch 13. Similarly, the contact 11b is connected to one of the control power terminals 15 via the other contact of the relay 12 and the switch 13. A movable contact of the switching contact 11 is connected to the other control power terminal 15. A normally closed contact 12a of the relay 12 is connected between the control power terminals 15.
A series circuit of an indoor fan 8 and an air blowing speed switch 14 is connected. Next, the operation will be explained. During heating, the heating switch 13 is closed, the drive coil 2a of the four-way valve is energized, and the four-way valve 2 is operated in a heating cycle. As a result, the high-temperature and high-pressure gas discharged from the compressor 1 passes through the west valve 2 as shown by the arrow, is cooled by the forced ventilation of the indoor fan 8 in the indoor heat exchanger 1#3, and becomes condensed liquid into the pressure reducing device 4. The refrigerant expands adiabatically to become a low-pressure refrigerant, is heated in the outdoor heat exchanger 5 by forced ventilation from the outdoor fan 9, evaporates, becomes a low-pressure gas, passes through the four-way valve 2, and is sucked into the compressor 1. As the outside temperature decreases, the amount of heat absorbed from the outdoor heat exchanger N5 into the refrigerant circuit 7 decreases, and the evaporation temperature decreases, and when it becomes below the zero point temperature, frost begins to form on the outdoor heat exchanger 5. As a result, the ability to absorb heat decreases, and the input pipe temperature of the outdoor heat exchanger 5 further decreases to below the set temperature. This temperature is detected by the defrosting condition detector 10, and by opening the contact 11a of the switching contact 11, the excitation of the drive coil 2a of the four-way valve is released, the four-way valve 2 is switched, and the refrigerant circuit 7
is in cooling operation. At the same time, the relay 12 is energized by closing the contact 11b, and its normally closed contact 12a is opened, stopping the indoor fan 8 from blowing air, thereby preventing cold draft to the occupants. At this time, one of the blower speed switches 14 is turned on. In this way, by switching the four-way valve 2 and entering cooling operation, the high temperature and high pressure refrigerant gas discharged from the compressor 1 is
After passing through the switched four-way valve 2, the outdoor heat exchange Wi
5, and the heat of the refrigerant dissolves the fog attached to it. When the temperature of the temperature sensing part of the defrosting condition detector 10 rises with the end of defrosting, the contact 11m of the switching contact 11 closes, the contact 11b opens, the coil 2a of the four-way valve 2 is energized again, and the four-way valve 2 will switch and return to heating operation.

[Problems to be solved by the invention]

However, in the conventional air conditioner described above, heating is not performed for a while during the defrosting operation and during the heating operation.
The indoor temperature drops, causing discomfort to the occupants. This invention was made to solve this problem, and provides an air conditioner that can prevent the indoor temperature from dropping during defrosting operation by controlling the room temperature setting, and does not cause discomfort to the occupants. aim to get

[Means to solve the problem]

The air conditioner according to the present invention is provided with a defrost control device that inputs detection signals from a defrost condition detector and a room temperature detector of an outdoor heat exchanger and raises a set room temperature before starting defrosting. .

[For use]

In this invention, before the start of defrosting, the defrost control device raises the set room temperature based on the detection signals from the defrost condition detector and the room temperature detector, which acts to suppress the drop in room temperature during defrosting operation. do.

【Example】

Embodiments of the air conditioner of the present invention will be described below based on the drawings. FIG. 1 is an electrical circuit diagram of one embodiment. In FIG. 1, parts that are the same as those in FIG. 7 are given the same reference numerals, and a description of the structure thereof will be omitted, and the explanation will mainly focus on the parts that are different from FIG. 7. As is clear from comparing Figure 1 with Figure 7,
In the figure, the defrosting control device 1r has the circuit configuration shown in FIG.
1+ mrrBi4 mountain [17)-Aal+? −
t, /7'1m; 1-S-This defrosting control device 1
6 is input terminal INI, IN2 and output terminal OUT 1
It is equipped with a defrosting condition detector 10 at the input terminal INI.
The detection signal is inputted. Further, a detection signal from the room temperature detector 17 is input to the input terminal IN2. The defrosting condition detector 10 is installed as shown in FIG. 6, and the room temperature detector 17 is installed in the room (not shown). The defrosting control device 16 is generally a microcomputer, and includes a program ROM, data RAM, A.
It has an LU (arithmetic unit). This defrosting control device 1
The output terminal 0UTI of 6 is adapted to switch the switching contact 11. That is, the defrosting control device 16 reads the detection signals inputted from the input terminals INI and IN2, and sends the signal from the output terminal 0UTI to the switching contact 11 that performs the defrosting operation. Other configurations are the same as in Figure 7,
Further, the configuration of the refrigerant circuit is also the same as that shown in FIG. Next, the operation of this embodiment will be explained with reference to the flowchart of FIG. 2 and the room temperature change diagram of FIG. 3. FIG. 2 is a flowchart showing the contents of the defrosting control device 16 that operates based on the output signal of the defrosting condition detector 10, and FIG. 3 shows changes in room temperature over time when defrosting operation is performed. First, in step 20 of FIG. 2, when a detection signal is received from the defrosting condition detector 10 during heating operation, the process moves from step 21 to step 22, and the room temperature is set in the room 1 detector 17. Command to increase ΔT and continue heating operation. Then, when the room temperature detector 17 reaches the newly set room temperature (T0 to T), the process moves from step 23 to step 24, and defrosting operation begins. This defrosting operation process is the same as the conventional one. Next, after the defrosting condition detector 10 completes defrosting, the process moves from step 25 to step 26 and returns to the original heating operation. The process of completing defrosting and returning to the original heating operation is the same as before. In the next step 27, the original set room temperature T is specified to the room temperature detector 17, and the operation returns to the initial heating operation state. In FIG. 3, immediately before the defrosting operation starts, the room temperature increases by ΔT (T+ΔT), but immediately after the defrosting operation ends, it does not fall below the original room temperature T. Here, the setting of the increased temperature ΔT may be changed depending on the indoor load. In addition, in the above embodiment, control was shown to raise the indoor temperature to (T + ΔT) immediately before the start of the defrosting operation, but it is also possible to start the defrosting operation after a certain period of time ΔS has elapsed after the room temperature setting has been increased. The same effect as in the above embodiment can be obtained even when the temperature is lowered.The time change of the room temperature in this case is shown in Fig. 5, and the flowchart showing the operation is shown in Fig. 4.In Fig. 4,
Even if the room temperature does not reach the set room temperature (T+ΔT) in step 23, if ΔS time has elapsed after the room temperature setting has been increased, step 28 enters the defrosting operation of step 24. The time △S should be determined by determining the temperature rise of the outdoor heat exchanger 5 when frosting occurs. [Effects of the invention] As explained above, the invention is provided with a defrost control device that raises the set room temperature before the start of defrosting operation, so it is possible to prevent the room temperature from dropping during defrosting operation without complicating the device, making it comfortable. This has the effect of providing a comfortable living space.

[Brief explanation of the drawing]

FIG. 1 is an electrical control circuit diagram during defrosting in an embodiment of the air conditioner of the present invention, and FIG. Fig. 4 is a flowchart showing the flow of operation of another embodiment of the air conditioner of the present invention, and Fig. 5 is a time change diagram of the room temperature of another embodiment of the same as above. 6 is a refrigerant circuit diagram of a conventional air conditioner, and FIG. 7 is an electrical control circuit diagram during defrosting of a conventional air conditioner. 1 compressor, 2 four-way valve, 2a four-way valve drive coil,
3 indoor heat exchanger, 4 pressure reducing device, 5 outdoor heat exchanger, 6 refrigerant piping, 7 refrigerant circuit, 8 indoor fan, 9
・Outdoor fan, 10 defrosting condition detector <11 - switching contact, 12 relay, 13 @ chamber switch, 16 defrosting control device, 17 room temperature detector. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Masuo Oiwa (and 2 others) Fig. 7 12: Nomu 16; Ei 207) Ko--/ 172tA#□ Fig. 2 Fig. 3 Room Fig. 5 Room 4 Fig. 4 Fig. 7 figure

Claims (2)

[Claims] (1) A refrigerant circuit configured to connect a compressor, a four-way valve, an indoor heat exchanger, a pressure reducing device, and an outdoor heat exchanger in a ring shape through refrigerant piping to allow refrigerant to pass therethrough; room temperature detection for detecting indoor temperature; a defrosting condition detector that detects the defrosting condition of the outdoor heat exchanger, and a defrosting condition detector that inputs the detection signals of the defrosting condition detector and the room temperature detector to increase the set temperature of the room temperature detector. An air conditioner equipped with a frost control device. (2) The air conditioner according to claim 1, wherein the defrosting control device controls the defrosting operation to start when a certain period of time has elapsed after the room temperature setting has been increased.