JPS62147252A - Defrosting operation of refrigerating cycle - Google Patents

Abstract

PURPOSE:To raise the suction temperature of a compressor before starting defrosting operation to heat the compressor and shorten a defrosting time utilizing the heat of the compressor by a method wherein the amount of ventilation is controlled by detecting the frosting of an outdoor heat exchanger and, thereafter, the defrosting operation is started. CONSTITUTION:The amount of ventilation is controlled by detecting the frosting of an outdoor heat exchanger 3 and, thereafter, defrosting operation is started. When a temperature sensor 11, provided in the outdoor heat exchanger 3, detects a temperature lower than -12 deg.C, for example, the preparation stage of defrosting is effected during a predetermined period of time. In the preparation stage of defrosting, the amount of ventilation of an indoor fan device 9 is reduced to reduce the amount of heat dissipation in an indoor side and the amount of ventilation of an outdoor fan device 10 is increased to increase heat absorption in an outdoor side while the capacity of a compreesor 1 itself is increased to increase the tempera ture of the compressor 1 itself. Then, the defrosting operation is effected when the preparation stage of defrosting has elapsed the predetermined period of time and an opening and closing valve 7, provided in a bypass circuit 8, is opened whereby high-temperature and high-pressure refrigerant gas, discharged out of the compressor 1, flows into an indoor heat exchanger 5 and the defrosting operation is effected while flowing a part of the same gas into the bypass circuit 8 to effect room heating.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a refrigeration cycle, and particularly to a defrosting operation method thereof.

[Technical background of the invention and points of interest]

The conventional method of operating a refrigeration cycle is to control the pressure during defrosting operation, operate the compressor at full capacity, and shorten the defrosting time. No improvements were made to this.

[Purpose of explanation]

The present invention was made in view of the above circumstances, and
The purpose of this is to raise the suction temperature of the pressure machine before defrosting starts, and then shut down the compressor and shorten the defrosting time by utilizing the heat of the compressor.

[Summary of the invention]

The present invention is a defrosting operation method for a refrigeration cycle that detects all the frost on an outdoor heat exchanger, controls the amount of air blown based on the detection, and then starts defrosting operation.

[Embodiments of the invention]

The central features of the present invention will be explained below with reference to the drawings.

In Figure 1, a compressor 1, a four-way valve 2, an off-site heat exchanger 3
, a pressure reduction device fjlt 4, and an indoor heat exchanger 5 are connected in sequence with a refrigerant pipe 6, and an on-off valve 7 is connected between the compressor 1 and the four-way valve 2 and between the outdoor heat exchanger 3 and the pressure reduction device 4. A refrigeration tank μ is constructed from a bypass circuit 8 which is connected to the bypass circuit 8.

The outdoor heat exchanger 3 and the indoor heat exchanger 5 are provided with an outdoor fan device 9 and an indoor fan device 10 facing each other. A control device 20 controls the compressor 1, the outdoor fan device 9, the indoor fan device 10, etc. before and after the start of defrosting.

Next, the operation of the refrigeration cycle μ configured as described above will be explained. When performing the entire cooling operation, the four-way valve 2 is connected as shown by the broken line, and the refrigerant flows in the direction of the broken line arrow.

The on-off valve 7 is closed.

That is, the high temperature and high pressure refrigerant scum discharged from the compressor 1 is
It passes through the four-way valve 2, condenses in the outdoor heat exchanger 3, reduces the pressure in the pressure reducing device 4, and evaporates in the indoor heat exchanger 5. The heat of vaporization at that time cools the room to be nitrided (not shown).

In addition, when performing heating operation, the two four-way valves are connected with a metal interleaved wire shape, and the refrigerant flows in the direction of the caustic arrow. The on-off valve 7 is closed.

That is, the high-temperature, high-pressure refrigerant gas discharged from the compressor 1211 passes through the four-way valve 2 and condenses in the indoor heat exchanger 5, is depressurized in the pressure reducing device 4, and evaporates in the outdoor heat exchanger 3.

Note that since the refrigerant radiates heat when condensing in the indoor heat exchanger 5,
This fever? Handling space that is not used and shown 1. ．． This will heat the room.

If the heating operation continues for a certain period of time (for example, about 40 minutes), frost will completely form on the surface of the outdoor heat exchanger 3, and therefore a defrosting operation to remove the frost from the outdoor heat exchanger 3 will be required.

The defrosting operation is performed by the control device 20.

That is, the indoor fan device 9, the outdoor fan device 10, the compressor 1, and the on-off valve 7 are controlled by the control device 20 as shown in FIG. 2 before, during the preparatory stage, and during the defrosting operation.

The fan rotation of the indoor fan unit 9 and the outdoor fan unit llo is set to 1,113 times (Iil>H2>H3, h
l>h2>h3), and the capacity of compressor 1 is 02(C1>C
2) Turn off the on-off valve 7.

For example, if the temperature of the temperature sensor 11 provided in the outdoor heat exchanger 3 is %
When a temperature of 2° C. or lower is detected, the defrosting preparation stage begins for a predetermined period of time (for example, 5 minutes). The defrosting preparation stage is performed to raise the suction temperature of the compressor 1, warm the compressor 1, and utilize the heat of the compressor 1 to shorten the removal time. At the defrosting preparation stage,
The fan rotations of the indoor fan unit @9 and the outdoor fan unit IO are respectively set to H2, and the capacity of the h2 compressor 1 is set to 01 (in this case, the on-off valve 7 is in the OFF state).

That is, the indoor fan device 9 is connected from 111 to H2 (Ml>■2
) and the amount of air blown in
By reducing the amount of heat and the radiation on the indoor side, the suction temperature of the compressor 1 is increased and the compression cell is warmed. Also, outdoor fan expression 10 from h2 to hl (h2
<hl) and by increasing the amount of air blown on the outdoor side and increasing the heat absorption on the outdoor side, the compressor 1 is warmed by the entire suction temperature of the compressor 1. Furthermore, the capacity of compressor 1 is increased to 02
By increasing the capacity of C1 (C2〈C1) and compression P)1 itself, we have increased the power of 6 pressure II machines and 1 machine itself.

Defrost! ! - Once the new stage has passed, defrosting operation begins.

To start the defrosting operation, the on-off valve 7 provided in the bypass circuit 8 is opened.

Then, the high-temperature, high-pressure refrigerant gas discharged from the compressor h1 flows to the indoor heat exchanger 5 and also partially flows to the pie bus circuit 8 (as shown by the dashed dotted line in 1), thereby performing defrosting operation while heating the room.

The high-temperature surface-pressure refrigerant that has flowed into the bypass circuit 8 flows into the outdoor heat exchanger 3, and uses its heat to remove frost formed on the surface of the outdoor heat exchanger 3.

In addition, a portion of the high-temperature, high-pressure refrigerant gas that has flowed into the indoor heat exchanger 5 and the refrigerant gas discharged from the compressor 1 is transferred to the V-internal heat exchanger 5.
, flows to the pressure reducing device 4, joins with the refrigerant from the bypass circuit 198, passes through the outdoor heat exchanger 3 and the four-way valve 2, and returns to the compressor l. During the defrosting operation, the outdoor fan device 10 is in an OFF state.

When the defrosting operation is continued for a certain period of time and the temperature of the temperature sensor 11 provided in the outdoor heat exchanger 3 becomes, for example, 5° C. or higher, the defrosting operation is ended. Defrosting operation is performed by closing the on-off valve 71 provided in the pie bus circuit 6.

In this embodiment, the indoor fan device 9, the outdoor fan device N10, and the pressure 8 device 1 were all controlled during the defrosting preparation stage 2, but the present invention is limited to this. All you have to do is to do at least one of them without being forced to do so.

Also, in this embodiment, defrosting is not performed while heating.

〔Effect of the invention〕

As described above, the present invention is a method of defrosting a refrigeration cycle in which frost formation on an external heat exchanger is detected, the blower is controlled based on the detection, and defrosting is then fully started. Before the start of defrosting, the suction temperature of the compressed rock is raised to 4#, which has the effect of shortening the defrosting time by utilizing the heat of the compressor.

[Brief explanation of drawings]

FIG. 1 shows (1) a refrigeration cycle showing an embodiment of the present invention.
FIG. 2 is a diagram showing an embodiment of the control method of the present invention. 3...Outdoor heat exchanger, 20...Control device. Agent Patent Attorney Tsutomu Chika Personality Yuki Yuyama Fainting −

Claims (3)

[Claims] (1) A defrosting operation method for a refrigeration cycle, characterized in that frost formation on an outdoor heat exchanger is detected, the amount of air blown is controlled based on the detection, and then defrosting operation is started. (2) A defrosting operation method for a refrigeration cycle according to claim (1), characterized in that the amount of air blown is controlled indoors and the amount of air blown is reduced. (3) A defrosting operation method for a refrigeration cycle according to claim (1), characterized in that the amount of air blown is controlled to the outdoor side and the amount of air blown is increased.