JPH0248780Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a refrigeration cycle device comprising a plurality of accumulators connected in series on the suction side of a compressor.

[Technical background of the invention and its problems]

In refrigeration cycle equipment such as a heat pump type that uses a compressor to operate the refrigeration cycle, when the load suddenly decreases significantly, the opening of the pressure reducing device cannot be adjusted in time and steam with high humidity is released. It is known that there is a risk of damage to the compressor due to the generation of liquid hammer when it is sucked into the compressor.

Therefore, in such a refrigeration cycle device, an accumulator is installed on the suction side of the compressor in order to prevent this. In such a refrigeration cycle device, if the amount of refrigerant is large and there is a risk that steam with excessive humidity may be sucked into the compressor, conventionally, as shown in Fig. 4, the suction side of the compressor a is A plurality of accumulators b are connected in series to alleviate the suction of steam with high humidity.

Such an accumulator b is constructed by providing a conduit e with a liquid return hole d formed at its tip in the lower part of a tank c, and connects the upper side of the tank c to the inlet and the conduit e to the lower part of the tank c. A plurality of tanks are connected in series to the suction side of the compressor a on the outlet side, and the refrigerant is separated inside each tank c to store a liquid portion. In other words, each accumulator b... serves as a damper against excessive refrigerant.

However, in the past, these series-connected accumulators b...
Since the diameter of the liquid return hole d is the same, it is difficult to use during transient periods when the suction pressure suddenly increases, such as when reversing the cooling/heating operation cycle or switching to defrosting operation. Under the most severe conditions,
There is an inconvenience that a large amount of liquid refrigerant accumulated in the accumulator b located closest to the compressor a returns to the suction side of the compressor a at once. Therefore, under the most severe cycle conditions during the transient period, the compressor a
When an abnormally high load is applied to the motor, many problems can occur, such as abnormal sliding friction and abnormal current peaks that cause malfunctions. is requested.

[Purpose of invention]

This invention was made with attention to the above circumstances, and its purpose is to provide a refrigeration cycle device that can reduce the return of liquid refrigerant to the compressor during the transient period of the accumulator. .

[Summary of the invention] In other words, this invention is based on the opening area of the liquid return hole of the accumulator closest to the compressor among the multiple accumulators connected in series on the suction side of the compressor. By making the opening area larger than the opening area of the liquid return hole, the liquid refrigerant is constantly returned from the accumulator to the compressor by the increased opening area, and the liquid refrigerant is kept in the accumulator closest to the compressor. The purpose is to prevent the liquid refrigerant from accumulating and to suppress the amount of liquid refrigerant that returns during the transient period.

[Example of idea]

This invention will be explained below based on the first embodiment shown in FIG. 1 is a compressor, and 2 is an accumulator. The accumulator 2 is constructed by providing a conduit 5 in the lower part of a tank 3 with a liquid return hole 4 formed at its tip. The accumulator 2 is connected to the suction pipe 1a constituting the suction side of the compressor 1, with the pipe line 6 provided on the upper side of the tank 3 serving as the inlet and the pipe line 5 serving as the outlet. multiple,
For example, two units are connected in series. However,
It is possible to separate the refrigerant and store the liquid inside each accumulator 2, 2. Of these accumulators 2, 2, the diameter of the liquid return hole 4 of the accumulator 2a located closest to the compressor 1 is larger than that of the liquid return hole 5 of the other accumulator 2b. The opening area of only the accumulator 2 closest to the compressor 1 is made larger.

The discharge pipe 1b of the compressor 1 to which such accumulators 2, 2 are connected, and the conduit 6 on the inlet side of the accumulator 2b disposed on the end side.
For example, refrigeration cycle equipment (all not shown) such as a four-way valve, an indoor heat exchanger, a pressure reduction device, and an outdoor heat exchanger are provided between the refrigeration cycle device and the heat pump type refrigeration cycle device.

Therefore, when performing air conditioning or heating using the refrigeration cycle device configured in this way, if the four-way valve is switched to the cooling side or the heating side and the compressor 1 is operated, the refrigerant compressed by the compressor 1 is transferred to the refrigeration cycle. After flowing through the equipment to form a cooling cycle or a heating cycle, it passes through each accumulator 2, 2 and returns to the compressor 1 again for cooling or heating operation. Then, while the refrigerant passes through each of the accumulators 2, 2, the liquid portion is separated and the liquid refrigerant accumulates in the accumulators 2, 2.

Here, under the most severe cycle conditions during a transient period in which the suction pressure temporarily increases rapidly, such as when reversing the cycle of cooling/heating operation or switching to defrosting operation, the accumulator 2a located closest to the compressor 1 It has been pointed out that a large amount of the liquid refrigerant accumulated in the compressor returns to the suction side of the compressor 1 at once, but this invention can improve this problem.

That is, according to this invention, the opening area of the liquid return hole 4 of the accumulator 2a located closest to the compressor 1 is the same as that of the other accumulator 2b.
The opening area of the liquid return hole 4 is larger than that of the liquid return hole 4.
This means that the accumulator 2 near the compressor 1
In a, during each refrigeration cycle operation such as cooling operation and heating operation, that is, at all times, the liquid refrigerant that would have accumulated in the tank 3 returns to the suction side of the compressor 1 by the amount that the opening area of the liquid return hole 4 is increased. This makes it harder for liquid refrigerant to accumulate. Therefore, the accumulation of refrigerant in the accumulator 2a closest to the compressor 1 can be made as small as possible, and even if the suction pressure suddenly rises temporarily, the accumulation of refrigerant in the accumulator 2a can be minimized. Since the amount of liquid refrigerant that accumulates is small, the return of liquid refrigerant to the compressor 1 can be suppressed.

Therefore, by reducing the return of liquid refrigerant during the transient period, it is possible to avoid the occurrence of an abnormally high load on the compressor 1, and to prevent abnormal current peaks that can cause abnormal sliding friction and malfunction. It is possible to prevent this from occurring.

Furthermore, this invention is not limited to the first embodiment described above, and may be implemented as the second embodiment shown in FIG. 2 or the third embodiment shown in FIG. 3. .

That is, in the case shown in FIG. 2, the diameter of the liquid return hole 4 of each accumulator 2 connected in series is
In the third example, the number of liquid return holes 4 of each accumulator 2 connected in series is increased as the number approaches the compressor 1. Increase compressor 1
The opening area of the liquid return hole 4 of the accumulator 2a closest to the accumulator 2a is made larger than that of the liquid return hole 4 of the other accumulator 2b, and even with this arrangement, the same effect as in the first embodiment described above can be obtained. play.

[Effect of idea]

As explained above, according to this invention, as the opening area is increased, liquid refrigerant is constantly returned to the compressor from the accumulator closest to the compressor, and the liquid refrigerant is returned to the accumulator closest to the compressor. This makes it possible to prevent liquid refrigerant from accumulating.

Therefore, it is possible to suppress the amount of liquid refrigerant that returns during the transient period, which is the most severe in terms of the cycle, and it is possible to reduce the return of liquid refrigerant from the accumulator to the compressor during the transient period.

Therefore, it is possible to avoid the generation of an abnormally high load on the compressor, and to prevent the generation of abnormal current peaks that may cause abnormal sliding friction and malfunction.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a first embodiment of this invention, Fig. 2 is a sectional view showing a second embodiment of this invention, and Fig. 3 is a sectional view showing a third embodiment of this invention. , FIG. 4 is a sectional view showing the vicinity of a plurality of accumulators connected in series in a conventional refrigeration cycle device. 1...Compressor, 2...Accumulator, 4...Liquid return hole.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a refrigeration cycle device configured by connecting multiple accumulators in series on the suction side of a compressor, the opening area of the liquid return hole of the accumulator closest to the compressor. A refrigeration cycle device characterized in that the opening area of the liquid return hole is larger than that of other accumulators. (2) The refrigeration cycle device according to claim 1, wherein the opening area of the liquid return hole of the accumulator increases as it approaches the compressor.