JPS641495Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the improvement of a hermetic electric compressor mainly used for refrigeration and cooling.

Conventionally, this type of hermetic electric compressor houses an electric element 2 and a compression element 3 in an airtight container 1 as shown in FIGS. 1 and 2, and lubricating oil A is stored at the bottom of the container to rotate The rotation of the shaft 4 supplies this lubricating oil to predetermined sliding parts. The compression element 3 includes a cylinder 5 and a frame 6 that closes both open ends of the cylinder 5.
and the compression chamber 8 formed by the cylinder head 7
The eccentric rotating shaft 4 inserted into the cylinder and directly connected to the electric element 2, the rotor 9 fitted on the rotating shaft 4, and the guide groove 10 provided in the cylinder 5 in contact with the outer peripheral surface of the rotor 9 slide. The suction, compression, and discharge operations are performed by the rotation of the rotor 9 fitted to the rotating shaft 4.

The gas compressed in the compression chamber 8 is discharged from the discharge valve 12 and passes through the discharge muffler 13 and the discharge gas hole 14 provided in the cylinder 5 to the closed container 1.
It then spreads into the lower cavity A of the airtight container 1 through the gap between the electric elements 2, and spreads into the upper cavity B of the closed container 1, and is sent out of the container from the discharge pipe 15. By the way, in general, refrigerant gas mixes leaked lubricating oil into the compression chamber 8, and further, when it spreads from the discharge gas hole 14 into the lower cavity 1 of the sealed container, the lubricating oil is atomized from the lubricating oil surface. Suction. When this discharged gas containing a large amount of lubricating oil flows into the discharge pipe 15, it hits the inner wall surface of the closed container 1, the electric element 2, etc., and the contained lubricating oil turns into oil droplets and hits these. It adheres and then gradually descends.

However, the falling paths of these oil droplets are all exposed to the discharged gas flow blown upward, and in the end, a considerable amount of lubricating oil is mixed into the discharged gas again and is sent out from the discharge pipe 15. As a result, the lubricating oil mixed in the refrigerant adheres to the condenser and evaporator in the refrigeration circuit, which significantly impedes heat exchange. Additionally, since the lubricating oil stored at the bottom of the container is removed from the container, an extra amount of lubricating oil must be added, and if there is insufficient lubricating oil, it will not be possible to supply a sufficient amount of oil to the sliding parts. It was hot.

This invention is intended to eliminate the above-mentioned drawbacks of the prior art, and the compressor of this invention will be explained below with reference to embodiments shown in FIGS. 3 to 6. In other words, the first in the figure,
The same parts as those in FIG. 2 are indicated by the same reference numerals, but FIG. By providing a gap 17 with the inner wall surface of the closed container 1, a hollow lubricating oil return pipe 18 as shown in FIG. 6 is inserted using this gap as shown in FIGS. 3 and 5. The present invention is characterized in that the lower end opening 18a is opened below the surface of the lubricating oil, and the upper end opening 18b is opened into the lower part of the upper cavity of the closed container 1.

Since it is configured as above, compression element 3
The refrigerant gas containing lubricating oil is discharged from the container into the lower cavity A of the container, passes through the gap between the electric elements 2, and flows into the upper cavity B. When it hits the element 2, it becomes oil droplets, which are returned to the inner bottom of the container 1 without being exposed to the flow of refrigerant gas blown up from the compression element 3 through the return pipe 18. Therefore, the amount of lubricating oil sent outside of the sealed container 1 is reduced, preventing a decrease in heat exchange efficiency due to the above-mentioned causes in the refrigeration circuit, and reducing the amount of lubricating oil at the inner bottom of the sealed container 1. Since the amount of lubricating oil decreases, sufficient lubricating oil can be supplied to predetermined sliding parts.

In the above embodiment, the lubricating oil return passage is formed by a series of return pipes 18, but as shown in another embodiment in FIG. A gap 17 between the flat portion 16 provided on the outer peripheral surface of the portion 2a and the inner wall surface of the airtight container 1
A gap 19 between the outer circumferential surface of a rising wall 6a provided on the frame 6 of the compression element 3 and the inner wall surface of the closed container 1, the other half of which is in series contact with the end surface of the stator core portion 2a. It may also be configured by

In the compressor of this invention, as described above, the airtight container 1
Since the lubricating oil separated in the upper cavity of the tank is returned to the bottom of the container through a lubricating oil return passage that is blocked from the rising discharge gas flow, less lubricating oil is sent out to the outside of the container. Therefore, not only is the loss of lubricating oil at the bottom of the container reduced;
This has advantages such as being able to reliably prevent the adverse effects of the delivered lubricating oil on the condenser and evaporator in the refrigeration circuit.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view of a conventional hermetic electric compressor.
Fig. 2 is an enlarged sectional view of the main parts, Fig. 3 is a longitudinal sectional view showing an embodiment of the compressor of this invention, Fig. 4 is an end view of the electric element in Fig. 3 seen from above, and Fig. 5 The figure is a perspective view of essential parts showing one embodiment of the lubricating oil return passage forming means in the compressor of this invention, FIG. 6 is a perspective view of the return pipe therefor, and FIG. 7 is the lubricating oil return passage forming means. FIG. 7 is a longitudinal cross-sectional view of a compressor showing another embodiment. In the figure, 1 is a sealed container, 2 is an internal electric element, 2a is a stator core thereof, 3 is a compression element, 6 is a frame, 6a is a rising wall of this frame, and 17 and 19 are for forming lubricating oil return passages. The gap, 18 is the lubricating oil return pipe, A is the lubricating oil, A is the upper space, and B is the lower space. In other figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (1) An electric element and a compression element driven by the electric element are housed in an airtight container, and discharged gas is introduced into an upper cavity formed above the electric element in the container. In a hermetically sealed electric compressor in which a discharge pipe for sending out of the container is opened, a return passage for lubricating oil separated from the discharged gas is formed between the inner wall surface of the container and the stator core of the electric element; The upper end opening of the return passage is closed off from other than the upper cavity in the container and opened to the lower part of this upper cavity, and the lower end opening of the return passage is opened into the lubricating oil stored in the inner bottom of the container. Features of hermetic electric compressor. (2) The separated lubricating oil return passage whose upper opening is opened in the upper cavity of the sealed container is a series of return passages inserted between the inner wall surface of the sealed container and the outer peripheral surface of the stator core of the internal electric element. A hermetic electric compressor according to claim 1, which is formed of a return pipe. (3) One half of the separated lubricating oil return passage opened in the upper cavity of the sealed container is formed by the gap between the inner wall surface of the sealed container and the stator core of the internal electric element, and the other half is formed by the gap between the inner wall surface of the sealed container and the stator core of the internal electric element. The closed type electric motor according to claim 1, which is registered as a utility model and is formed by a gap between an upright wall provided on a frame of a compression element that is brought into contact with an end face of an iron core part and an inner wall surface of the closed container. compressor.