JPS6237978Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an oil separation device for a hermetic two-stage refrigerant compressor.

Figures 1 and 2 are diagrams showing the refrigerant flow in a conventional hermetic two-stage refrigerant compressor. 4 is the suction port on the high stage side H, 5 is the discharge port on the high stage side H, 6 is the crank chamber, 7
is the electric motor room. Note that the pressures in the crank chamber 6 and the motor chamber 7 are intermediate pressures.

Next, the flow of refrigerant will be explained. First, refrigerant gas evaporated in an evaporator (not shown) is sucked into the compressor through the suction port 2 on the low stage side L. The refrigerant gas compressed on the low stage side L is cooled by an intercooler (not shown) on the way from the discharge port 3 on the low stage side L to the suction port 4 on the high stage side H. It is sucked into the motor room 7. Then, after being recompressed on the high stage side H, it is discharged from the high stage side discharge port 5.

As can be seen from the refrigerant flow above, the low stage L
The cylinder pressure varies from low pressure to intermediate pressure,
Further, the cylinder internal pressure on the high stage side H fluctuates from intermediate pressure to high pressure. Therefore, the crank chamber 6 of the compressor
Since the internal pressure is an intermediate pressure, there is inevitably a lot of oil coming up from the cylinders on the low stage L side. Therefore, since refrigerant gas containing a relatively large amount of oil is sucked into the motor chamber and discharged from the high stage side H, there is a drawback that there is a lot of oil coming out of the compressor.

This invention was made in order to eliminate the drawbacks of the conventional compressor as described above, and by providing an oil separator in the motor chamber, it provides a hermetic two-stage refrigerant compressor with less oil spillage as described above. The purpose is to

An embodiment of this invention will be described below with reference to the drawings. In FIGS. 3 and 4, 1 is a sealed casing, 7 is a motor chamber, 8 is an electric motor, 8a is a stator of the electric motor, 8b is a rotor of the electric motor, and 9 is a rotor 8.
10 is a tubular centrifugal pump installed in close contact with the inner wall surface of the conical rotating body 9; 11 is the conical rotating body 9 and the centrifugal pump 10;
12 is a motor chamber cover plate, 13 is a strainer, and 14 is a conical stationary guide fixed to the inner surface of the motor chamber cover plate 12.

Next, a description will be given of how the oil separation device shown above acts in the refrigerant flow of the hermetic two-stage refrigerant compressor with the crank chamber pressure set to intermediate pressure.

One characteristic of a two-stage compressor in which the crank chamber pressure is an intermediate pressure is that more oil rises from the lower-stage cylinder than in a two-stage compressor in which the crank chamber pressure is a low pressure. Therefore, refrigerant gas containing a relatively large amount of oil flows to the high stage side H.
reaches the suction port 4. After passing through the strainer 13 and the conical stationary guide 14, it is introduced into the passage formed by the inner wall surface of the conical rotating body 9 and the outer wall surface of the guide 14. Here, centrifugal energy is added to the oil-containing refrigerant gas by the rotating body to increase the flow velocity. At this time, since the oil content in the refrigerant gas has a larger mass than the gas content, the oil content and gas content are separated immediately after passing through the narrow flow path, and only the gas content is sucked into the high-stage cylinder. hand,
It is discharged from the discharge port 5. In addition, the centrifugal pump 10
performs the function of reinforcing the rotating body 9 and the function of effectively adding centrifugal energy to the refrigerant gas in the above-mentioned actions.

As described above, according to this invention, the oil content in the refrigerant gas is forcibly separated in the motor room, so the amount of oil coming up is reduced and stable operation of the two-stage refrigerant compressor is maintained. It becomes possible. It also has advantages such as improved heat transfer efficiency of the heat exchanger, increased refrigeration capacity, and improved operating efficiency of the device.

[Brief explanation of the drawing]

Figures 1 and 2 are diagrams showing refrigerant flow in a conventional hermetic two-stage refrigerant compressor, and Figure 3 is an electric motor of a hermetic two-stage refrigerant compressor equipped with an oil separation device according to an embodiment of this invention. FIG. 4 is a sectional view showing the side, and FIG. 4 is a perspective view of the conical rotating body used in this invention. In the figure, 1 is a sealed casing, 4 is a suction port, 6 is a crank chamber, 7 is a motor room, 8 is an electric motor, 8b is a rotor, 9 is a conical rotating body, 10 is a tubular centrifugal pump, and 12 is a motor room cover. board, 13 is a strainer, 1
4 is a conical stationary guide. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a two-stage refrigerant compressor in which the mechanical part and the electric motor part are housed in a sealed casing, and the pressure in the crank chamber and the pressure in the electric motor chamber are both intermediate pressures, The present invention is characterized by comprising an oil separation device consisting of a conical rotating body fixed to the rotor of the electric motor, and a conical stationary guide fixed to the motor chamber cover plate and provided facing the conical inner surface of the rotating body. A hermetic two-stage refrigerant compressor. (2) The hermetic two-stage refrigerant compressor according to claim 1, which has a tubular centrifugal pump disposed on the inner surface of a conical rotating body. (3) Utility model registration claim No. 1 in which a strainer communicating with the suction port is provided inside the conical guide.
The hermetic two-stage refrigerant compressor according to item 1 or 2.