JPS6352237B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a hermetic scroll compressor for refrigeration air conditioning (room air conditioners, package air conditioners, chiller units, freezer/refrigeration units, refrigerators, etc.) or for helium liquefaction. be.

[Conventional technology]

Hermetic scroll compressors have two types: an all-intermediate-pressure semi-hermetic system (shown in Figure 1) in which the entire chamber and back pressure chamber, except for the compression element and the inside of the compression chamber, are at an intermediate pressure (as shown in Figure 1); There is a completely sealed low-pressure chamber system (for example, Japanese Patent Application Publication No. 53-35840) in which the suction pressure is applied to all other parts except for the suction pressure.

A hermetic compressor is constructed by housing a compression element main body and a motor serving as a driving source in one sealed chamber. In hermetic compressors for air conditioning, the drive shaft is generally arranged vertically. This is so that the material can be sucked from the shaft end and supplied to each sliding part. The scroll compressor according to the present invention also basically has the same configuration as above.

The basic structure of a hermetic scroll compressor will be explained with reference to the all-intermediate-pressure chamber type shown in FIG.
The scroll compressor includes a fixed scroll 3 formed by vertically forming a spiral wrap 2 made of an involute curve or a curve similar to the involute curve on a disk-shaped end plate 1, and a fixed scroll 3 formed by standing upright a spiral wrap 2 made of an involute curve or a curve similar to this, and a disk-shaped end plate 4 with a spiral wrap 2 having the same shape as the wrap 2. and an orbiting scroll 6 formed by standing up the wraps 5 of the orbiting scroll 6, the wraps 2 and 5 are engaged with each other with the laps 2 and 5 facing inward, and the rotation of the orbiting scroll 6 is prevented,
An Oldham ring 7 is provided between the stationary part (frame 9 in this example) to which the fixed scroll 3 is fixed and the orbiting scroll 6 so that the center of the orbiting scroll moves in a planetary circle around the center of the fixed scroll 3. It is something. On the other hand, the frame 9 is press-fitted into the chamber 13 or fixed by other methods.
The orbiting scroll 6 is mounted on the bearing portion 9a at the center of the
A crankshaft 8 for driving is supported, and a pin portion of the crankshaft, ie, a crank pin 8a, is inserted into a bearing portion 4a formed inside the end plate boss portion of the orbiting scroll. The center of the crankshaft 8 coincides with the center of the fixed scroll 3, and the center of the crank pin 8a coincides with the center of the orbiting scroll 6. The distance between the center of the crankshaft 8 and the center of the crank pin 8a is the radius of the planetary circular motion of the orbiting scroll 6, that is, the turning radius. The rotational force of the crankshaft 8 is given by a rotor 11 fixed thereto, and the rotational force of the rotor 11 is obtained by electrical energy supplied to the windings of the stator 12 via a hermetic terminal (not shown). It will be done. That is, a motor is constituted by a rotor 11 and a stator 12 (note that 10 is a balance weight).

At the end of the crankshaft 8 opposite to the crank pin 8a, an oil frying tip 18 for frying oil is provided, as shown in the figure, and an oil lifting hole 19 is formed inside the crankshaft 8, which is inclined with respect to the axis center line. has been done. As a result, the lubricating oil 20 stored at the bottom of the chamber 13 is transferred to the oil supply holes 21 and 22 which communicate with the oil pumping hole 19 mainly by the centrifugal force of rotation.
It is supplied to the sliding surfaces of bearings 9a and 4a through.

Wraps 2 and 5 spirals are fixed scrolls 3
Assuming that it is formed counterclockwise when viewed from the side,
When the center of the orbiting scroll 6 rotates clockwise around the center of the fixed scroll 3 (as viewed from the fixed scroll side), a closed space, that is, compression, is formed between the end plates 1 and 4 and the laps 2 and 5. The chamber 15 shrinks from its maximum volume at the end of the wraps 2, 5 as it moves toward the center. By repeating this movement, low-pressure gas can be sucked through the suction port 14 and discharged as high-pressure gas from the discharge port 16. However, when this device is in operation, a force that tends to separate the fixed scroll 3 and the orbiting scroll 6 is generated by the fluid pressure within the compression chamber 15. Therefore, if this continues, both scrolls 3 and 6 will separate and normal compression operation will become impossible. Therefore, fluid force such as gas pressure or oil pressure, or mechanical force such as spring force is applied to
It must be applied to the anti-lap surface of 3 and 6 to hold them together so that they do not separate. When this force is to be applied by gas pressure, as shown in FIG. This is achieved by providing a small hole (back pressure hole 17) and guiding the pressure (intermediate pressure) in the compression chamber to the back pressure chamber 25.

To ensure stable operation of the compressor, it is necessary to supply lubricating oil to the sliding surfaces of each sliding element, especially the bearing part 9a.
and 4a is required. However, there is a limit to the amount of lubricating oil 20 that can accumulate at the bottom of the chamber, and after the oil supplied to the bearings 9a and 4a leaks from the bearings, it becomes a mist from the back pressure chamber 25, and the oil supplied to the bearings 9a and 4a is turned into mist from the back pressure chamber 25. It is used to lubricate the sliding surfaces of both end plates 1 and 4, and a part of it enters the suction chamber from the sliding surfaces of both end plates 1 and 4, or enters the compression chamber 15 from the back pressure hole 17 and lubricates the discharge gas. As a result, the amount of lubricating oil at the bottom of the chamber 13 gradually decreases, making it impossible to fry oil.
For this reason, in the example shown in Figure 1, an oil separator (not shown) is installed outside the compressor and connected to the discharge pipe.
The separated oil is sent to the inside of the chamber 13 through an oil return pipe 24.
I'm trying to get it back through.

[Problems to be Solved by the Invention] The above-mentioned all-intermediate pressure type compressor does not have a function within the compressor itself to separate the oil that lubricates the sliding parts of each part of the machine, especially the bearing parts. That is, it is necessary to once guide the discharged gas to an oil separator (not shown), separate the gas and lubricating oil there, and then return the lubricating oil from the oil separator to the bottom of the chamber 13 through the oil return pipe 24. If this is not done, the lubricating oil at the bottom of the chamber will run out within a few minutes, and the bearings will no longer be lubricated, causing the bearings to seize and the compressor to lose its function. Also, since most of the cooling of the motor must be done through lubricating oil, an oil cooler is also required.

In conventional all-low-pressure chamber type compressors (cited example above), suction gas is first introduced into the motor chamber inside the chamber, where the gas and oil are separated, and at the same time, the suction gas cools the motor. I'm letting them do it. The problems in this case are: (1) The suction gas becomes superheated, resulting in a significant drop in performance. (2)
It is necessary to prevent the orbiting scroll from separating from the fixed scroll due to the gas pressure inside the compression chamber by a mechanical method (in the case of the cited example, a thrust bearing), which increases mechanical loss (sliding friction loss).
etc. In addition, the compressed gas mixed with oil is discharged into the discharge chamber, where it is separated into oil and gas, the gas is directly discharged from the discharge chamber to the outside, and the oil is dropped into the motor chamber below. Are known. (Japanese Patent Laid-open No. 55-46081) However, since the gas is directly discharged to the outside from the discharge chamber, the gas stagnates inside the motor chamber, making it difficult to release the heat generated by the motor to the outside. .

In addition, since the gas is directly discharged from the discharge chamber to the outside, oil droplets floating in the discharge chamber are accompanied by the flow of the discharged gas and are discharged to the outside, which means that oil separation is not performed sufficiently. High fear.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hermetic scroll compressor that has a simple structure, prevents oil and compressed gas from being remixed, and can perform good oil separation.

[Means for solving problems]

The above-mentioned object of the present invention is that a discharge chamber and a motor chamber are connected through a passage, and the passage opens at the upper part of the discharge chamber and mainly guides gas in the discharge chamber to the motor chamber. This is achieved by comprising a first passage and a second passage that opens at a position lower than the opening position in the discharge chamber of the first passage and mainly guides oil in the discharge chamber to the motor chamber.

[Effect]

With the above configuration, the compressed gas and oil separated in the discharge chamber are guided to the motor chamber via the first and second passages, respectively, so when the gas and oil separated in the discharge chamber flow into the motor chamber, Mixing is eliminated, and the oil can be easily introduced into the bottom region of the motor chamber, allowing for good oil separation.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 2 to 5.

FIG. 2 shows a first embodiment of the invention. In this embodiment, the chamber 13 is a fixed scroll 3
and has an inner diameter equal to the outer diameter of the frame 9, and by increasing the length upward compared to the example of FIG. 1, the inlet end is located above the anti-lap surface of the end plate 1 of the fixed scroll, Together with a lid chamber 30 that closes this inlet end, a discharge chamber 31 is formed on the opposite side of the end plate 1 of the fixed scroll. By providing such a space 31, gas and lubricating oil can be separated. The thickness of the outer periphery of the end plate 1 of the fixed scroll on the side opposite to the lap is smaller than that of the central part, so that an oil sump groove 32 for collecting oil after separation is formed between it and the inner periphery of the chamber 13. be done. In addition, oil drain holes 35 and 36 are provided from the bottom of this oil sump groove 32 to vertically penetrate through the end plate and frame of the fixed scroll. ) 43a. The gas passes through the lid chamber 30 and is connected to the discharge gas take-off pipe 40 that opens above the discharge chamber 31 to the outside of the chamber 13, and after being cooled or as it is, returns to the inside of the chamber 13 through the return pipe 41. Return to. As a result, the motor chamber is cooled and the oil is reseparated, and the gas is finally taken out from the discharge pipe 42 to the outside. Therefore, in this embodiment, by providing the discharge chamber 31, gas can be discharged in the closed space formed by the chamber 13 and the lid chamber 30 by simply adding one system of gas piping from piping 40 to 41. This makes it possible to separate oil from oil. As in the case of FIG. 1, the force of the orbiting scroll 6 pressing against the fixed scroll 3 is generated by the gas pressure led from the back pressure hole 17 provided in the end plate 4 of the orbiting scroll and the rotation through the oil pumping hole 19. It is obtained by the hydraulic pressure (substantially discharge pressure) flowing into the engagement portion between the scroll 5 and the crankshaft 8. The back pressure chamber 25 needs to be maintained at an intermediate pressure and is sealed from other high pressure parts such as the upper motor chamber 43a. Therefore, the joint surface between the fixed scroll 3 and the frame 9 is
Sealed by a ring (not shown). From the sliding surface 19 of the crankshaft 8 to the bearings 9a and 4
The lubricating oil supplied to a is mixed with gas or liquid dissolved in the oil under high pressure, and these are separated from the oil leaking into the back pressure chamber 25 and reduce the pressure inside the back pressure chamber 25. There is a possibility that this may increase. However, the amount of leakage can be kept within a certain limit by adjusting the bearing gap or the length of the bearing, and the back pressure can be maintained at a predetermined level by moving the position of the back pressure hole 17 slightly to the low pressure side.

The embodiment shown in FIG. 3 is a development of the embodiment shown in FIG. 2, in which gas and oil are separated more actively. ing. The separated oil is taken out from notches 44 and 45 provided on the outer periphery of the end plate 1 and frame 9 of the fixed scroll through an oil take-out pipe 46, and is then taken out to the outside through an oil return pipe 47 to the space below the motor (lower motor chamber). Return to 43b. With this configuration, the discharge chamber 31
The separation of oil in the upper motor chamber 43a is improved, and there is no risk of remixing of gas and oil in the upper motor chamber 43a, which could occur in the embodiment of FIG. Therefore, more effective oil separation is possible. Furthermore, oil extraction pipe 4
6 and the return pipe 47 system (not shown).
It is also possible to cool the oil.

The embodiment shown in FIG. 4 is a further development of the embodiments shown in FIGS. 2 and 3, and the upper motor chamber 43a and the gas and oil from the discharge chambers (discharge chamber 31a and lower discharge chamber 31b) are The introduction into the lower motor chamber 43b is performed entirely within the chamber without using external piping. Gas flows from a discharge pipe 55 opening to the upper part of the oil separation element 39, that is, the upper discharge chamber 31a, to a gas passage hole 54 passing through the end plate 1 and frame 9 of the fixed scroll.
and 53 to the upper motor chamber 43a, and oil is similarly sent to the lower motor chamber 43b through oil drain holes 53 and 36 penetrating the end plate 1 and frame 9 of the fixed scroll and the joint pipe 52. Therefore, according to this configuration, gas and oil can be separated almost in the same manner as in the embodiment shown in FIG. 3, and there is an advantage that no external piping is required.

The embodiment shown in FIG. 5 is basically the same as the embodiment shown in FIG. 4 with respect to separation of gas and oil, but the discharge pipe 55 in the embodiment shown in FIG. 4 is not required. That is, thick parts 58 and 57 are provided at the central part (where the discharge port 16 is provided) and the outer peripheral part of the end plate 1 of the fixed scroll, and an oil reservoir 61 is formed around the central thick part 58. This oil sump 6
The oil accumulated in the fixed scroll head 1 is drained into the lower motor chamber 43b through the vertical holes 62 and 64 provided in the end plate 1 of the fixed scroll, the horizontal hole 63, each oil drain hole of the through hole 36 provided in the frame 9, and the connecting pipe 52. sent to. A ring-shaped oil separation element 39' is arranged on the outer periphery of the oil reservoir 61. The gas discharged from the discharge port 16 passes through the oil separation element 3
9', the oil is separated and escapes into the space 31a outside the element. The gas from which the oil has been separated flows into the upper motor chamber 43a through discharge gas passages 65 and 66 in the form of round holes or square notches provided on the outer periphery of the end plate 1 and frame 9 of the fixed scroll.

As described above, according to these embodiments, in the hermetic scroll compressor, the compressor itself is provided with oil separation and oil supply means, so that the motor is cooled by the discharged gas, and the oil inside the hermetic chamber is cooled. The task of ensuring separation and lubrication has been achieved and the effect is extremely significant.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a hermetic scroll compressor which can prevent remixing of oil and compressed gas with a simple structure and can perform oil separation well.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing the basic structure of a hermetic scroll compressor, and FIGS. 2 to 5 are longitudinal sectional views showing various embodiments of the present invention. 1, 4... End plate, 2, 5... Wrap, 3... Fixed scroll, 6... Orbiting scroll, 8... Crankshaft, 9... Frame, 13... Chamber, 30... Lid chamber, 31... ...Discharge chamber, 3
2...Oil sump groove, 35, 36, 62, 63, 64...
...Oil drain hole, 39, 39'...Oil separation element,
43a... Upper motor chamber, 43b... Lower motor chamber, 52... Connecting pipe, 53, 54... Gas passage hole, 55... Discharge pipe.

Claims (1)

[Scope of Claims] 1. A discharge chamber is provided on the side opposite to the wraps of the fixed scroll, and a motor chamber is provided on the opposite side of the discharge chamber, with the fixed scroll and the orbiting scroll engaged with each other with their laps facing each other. In a hermetic scroll compressor configured such that compressed gas is discharged into a discharge chamber, then introduced from the discharge chamber into a motor chamber via a passage, and discharged from the motor chamber to the outside, the passage opens at the upper part of the discharge chamber and opens at a position lower than a first passage that mainly guides gas in the discharge chamber to the motor chamber and an opening position between the discharge chambers in the first passage;
What is claimed is: 1. A hermetic scroll compressor characterized by comprising a second passage that mainly guides oil in a discharge chamber to a motor chamber. 2. The seal according to claim 1, further comprising an oil separation element located inside the discharge chamber between an opening in the discharge chamber of the first passage and a discharge port formed in the fixed scroll. shaped scroll compressor. 3. The first passage and the second passage are each constituted by a through hole provided in an end plate of a fixed scroll and a frame coupled to the end plate, according to claim 1. Hermetic scroll compressor.