JPH03115791A - Scroll type compressor - Google Patents

Abstract

PURPOSE:To prevent the deterioration of the performance of a compressor to be caused by abrasion of a scroll lap and a fault by installing a permanent magnet in the wall surface of a back pressure chamber so as to attract the iron powder included in the lubricating oil with the permanent magnet. CONSTITUTION:The lubricating oil 21 stored in the lower of a sealing container 10 is supplied to an auxiliary bearing 7 and a main bearing 6 through an eccentric longitudinal hole 4b of a main shaft 4, and is flowed into a back pressure chamber 20 through each bearing space. At this stage, the micro iron powder generated in each bearing is flowed into the back pressure chamber 20 with the lubricating oil 21. Since the flowed iron powder is attracted by a permanent magnet 24 installed in the wall surface of the back pressure chamber 20, only the lubricating oil 21 is filled for supply into an operating chamber formed with both scrolls 1, 2 through a narrow hole provided in a mirror plate 2a of a turning scroll 2. Consequently, the abrasion of the scroll lap is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a scroll compressor used as a refrigerant compressor for refrigeration and air conditioning, refrigerators, and the like.

BACKGROUND OF THE INVENTION The operating principle and structure of a conventional scroll compressor are disclosed in, for example, Japanese Patent Publication No. 57-23793. Here, a conventional example will be explained with reference to this publication.

The basic structure, lubrication method, etc. will be explained with reference to FIGS. 2 and 3. In addition, for ease of explanation,
The flow direction of working gas is shown by a solid line arrow, and the flow direction of lubricating oil is shown by a broken line arrow. FIG. 2 shows the overall configuration of a conventional hermetic scroll compressor for air conditioning. The compressor includes a fixed scroll member 1 and an orbiting scroll member 2, which are compression element parts.
, the rotation prevention member 3 that prevents rotation of the orbiting scroll 2, the main shaft 4, the three bearings that support it, namely the orbiting bearing 5, the main bearing 6, the auxiliary bearing T, and the electric motor 8. It is composed of a stationary member block 9 for fixing the fixed scroll 1 and the like. These components are housed inside the closed container 10.

The operation of the compressor will be explained according to the flow of refrigerant gas and the flow of lubricating oil.

The low-temperature, low-pressure refrigerant gas is guided from the suction pipe 11 and reaches the suction chamber 12 within the fixed scroll 1 . As shown in FIG. 3, the refrigerant gas that has reached the compression element is moved into a closed space 13 formed by both scrolls due to the orbiting movement of the orbiting scroll 2, which is prevented from rotating.

As the refrigerant gas 13b gradually contracts and moves to the center of the scroll, the pressure of the refrigerant gas is increased and the refrigerant gas is discharged through the central discharge hole 14. The discharged high-temperature, high-pressure refrigerant gas fills the space 18 around the electric motor via the upper space 15 in the closed container 10 and the communication passages 16 and 17, and is guided to the outside via the discharge pipe 19.

On the other hand, a back pressure chamber 20 in a space surrounded by the back surface of the orbiting scroll 2 and the block 9 has a back pressure chamber 20 that counters the gas force in the thrust direction due to the gas pressure in a plurality of sealed spaces formed by both the orbiting and fixed scrolls. A pressure intermediate between the suction pressure and the discharge pressure of the reservoir acts. This intermediate pressure is set by providing small holes 2b and 2C in the end plate 2a of the orbiting scroll 2, and guiding the gas inside the scroll during compression to the back pressure chamber through the small holes 2b and 2C.
This is done by applying gas pressure to the back of the orbiting scroll.

Next, the flow of lubricating oil will be explained.

Lubricating oil 21 is stored in the lower part of the closed container 1o.

The lower end of the main shaft 4 is immersed in the oil at the bottom of the container, and the upper part of the main shaft is provided with an eccentric shaft portion 4a.
is engaged with. The main shaft 4 has an eccentric vertical hole 4b formed from the lower end of the main shaft to the upper end surface of the main shaft for supplying oil to each bearing section. The lower end of the main shaft 4 immersed in the lubricating oil 21 is in an atmosphere of high discharge pressure (Pd), while the downstream slewing bearing 5 is in an atmosphere of intermediate pressure (Pm). -Pm), the lubricating oil 21 at the bottom of the container rises inside the eccentric vertical hole 4b. Eccentric vertical hole 4b
The lubricating oil 21 that has risen is transferred to the auxiliary bearing 7. The main bearing 6 is supplied with oil, and the oil is drained into the back pressure chamber 2o through the respective bearing gaps. The lubricating oil that has reached the back pressure chamber 20 flows through the pores 2b and 2.
The refrigerant gas is injected into the working chamber formed by the scrolls 1 and 2 through the refrigerant gas and mixed with the refrigerant gas inside the scroll wraps 1b and 2d. Next, the lubricating oil along with the refrigerant gas is subjected to a pressure increasing action, and the discharge hole 14. The discharge chamber 15 further moves to the motor chamber 18 via communication passages 16 and 17. The lubricating oil that has reached the motor chamber 18 falls to the bottom of the container due to its own weight.

The fallen lubricating oil is collected again at the bottom of the container and used to lubricate each part.

In the scroll compressor configured as above,
As mentioned above, the supply of lubricating oil to each sliding part is carried out using the lubricating oil 21.
A high discharge pressure within the closed container 10 in which is stored;
The lubricating oil 21 rises through the eccentric vertical hole 4b of the main shaft 4 due to the pressure difference between the intermediate pressure of the slewing bearing 6 and the auxiliary bearing 7. The main bearing 6 is supplied with oil, and the oil is drained into the back pressure chamber 20. Further, the lubricating oil in the back pressure chamber 2° is injected into the working chamber formed by the scrolls 1 and 2 through the pores 2b and 2c, and is used to lubricate the scroll wraps 1b and 2d.

Problems to be Solved by the Invention However, in the above configuration, the lubricating oil supplied to each bearing portion and reaching the back pressure chamber 2o mainly contains sliding wear particles of the main shaft 4 due to sliding in each bearing portion. Contains a small amount of iron powder. Since the iron powder reaching the back pressure chamber 20 has a higher specific gravity than the lubricating oil, it gradually accumulates at the bottom of the back pressure chamber 2o.

Due to the sudden flow of lubricating oil when starting the compressor, etc.
The accumulated iron powder is stirred together with lubricating oil and injected into the working chamber, causing wear of the scroll wrap and causing a decrease in compressor performance and even failure.

The present invention solves these conventional problems,
The iron powder that accumulates in the back pressure chamber is firmly fixed inside the back pressure chamber,
A scroll type compressor is provided in which the flow is prevented from flowing into the working chamber.

Means for Solving the Problems In order to solve the above problems, a permanent magnet is attached to the wall of the back pressure chamber, and the iron powder contained in the lubricating oil is attracted to the permanent magnet. .

Function: By attaching a permanent magnet to the back pressure wall, the iron powder contained in the lubricating oil and flowing into the back pressure chamber is attracted to the permanent magnet and fixed in the back pressure chamber. does not flow into the working chamber of the scroll.

Example An embodiment of the present invention will be described below with reference to FIG.

In the figure, the same parts as in FIGS. 2 and 3 of the conventional example are designated by the same reference numerals.

In FIG. 1, 24 is a permanent magnet attached to the wall of the back pressure chamber 2o.

In the scroll compressor configured as above,
Lubricating oil 21 stored in the lower part of the closed container 1o is supplied to the auxiliary bearing 7° and the main bearing 6 through the eccentric vertical hole 4b of the main shaft 4, and flows into the back pressure chamber 2o through the respective bearing spaces.

At this time, a small amount of iron powder generated in each bearing portion flows into the back pressure chamber 20 together with the lubricating oil 21. Since the iron powder that has flowed in is attracted to the permanent magnet 24 attached to the wall of the back pressure chamber 2o, only the lubricating oil is transferred to the end plate 2 of the orbiting scroll 2.
Both scrolls 1 through pores 2b and 2c provided in &
, 2 is injected and supplied with oil.

As described above, according to the present invention, the permanent magnet attached to the wall of the back pressure chamber 20 causes the lubricating oil 2 to flow into the back pressure chamber.
Since the iron powder generated in each bearing part included in the bearing part 1 is separated and adsorbed from the lubricating oil 21, only the lubricating oil that does not contain iron powder can be supplied to the working chamber.

Therefore, there is an effect of preventing wear of the scroll wrap.

Effects of the Invention As described above, the present invention separates and adsorbs worn iron particles contained in lubricating oil in the back pressure chamber by attaching a permanent magnet to the wall surface of the back pressure chamber, and transfers the iron particles to the scroll operating chamber. Since it is possible to supply lubricating oil that does not contain oil, it has the effect of preventing compressor performance deterioration and failure due to scroll wrap wear.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll compressor according to an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view of a conventional scroll compressor, and FIG. 3 is a cross-sectional view showing the meshing state of the scrolls. . 1...Fixed scroll, 2...Orbiting scroll, 9...Block, 2o...
Back pressure chamber, 24...Permanent magnet.

Claims (1)

[Claims] A fixed scroll having a wrap and an orbiting scroll are engaged with each other with the wraps inside, and a block for fixing the fixed scroll and the orbiting scroll rotate relative to the fixed scroll in a state where rotation is prevented, and the orbiting motion is performed. a back pressure chamber formed by the block and a back surface opposite to the wrap of the orbiting scroll;
A scroll compressor characterized in that a permanent magnet is provided on a wall surface of the back pressure chamber.