JPH0666269A - Scroll fluid machine - Google Patents

Abstract

(57) [Summary] [Objective] Sufficient oil is made to flow into the radial groove 7 of the thrust bearing 8 to perform favorable thrust support of the orbiting scroll, and to define inside from the radial groove 7 via the outer peripheral region of the scroll. It reduces the amount of oil that rises in the working chamber and improves reliability. [Structure] The radial groove 7 provided in the thrust bearing 8 is connected to an oil return passage 70 through an oil sump portion 7a at an inlet portion without opening the radial groove 7 so as to be opened to the internal space of the casing and the thrust An annular groove 31 and an annular dam portion 32 are provided on the outer peripheral wall portion of the bearing 8, and the excess oil in the thrust bearing 8 is temporarily blocked by the annular dam portion 32, and the oil return passage 7
The amount of oil collected from the thrust bearing 8 and flowing out from the outer side of the thrust bearing 8 to the outer peripheral region of the scroll is reduced, and the amount of oil lifted up into the working chamber is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type fluid machine widely used as a refrigerant compressor for refrigerators and air conditioners.

[0002]

2. Description of the Related Art Conventionally, as disclosed in JP-A-1-105701 and as shown in FIG. 8, a fixed scroll F and an orbiting scroll O are disposed inside a casing D through a housing H, and a housing H is provided. Is provided with an accommodation chamber E for accommodating a counterweight W provided at an end portion of the drive shaft K and a crank portion C having a swing link L, and a support member is provided on a top surface portion of the housing H having an inner peripheral edge facing the accommodation chamber E. As clearly shown in FIG. 9 via G, an annular thrust bearing S having a support surface P for supporting the back surface of the orbiting scroll O and a large number of radial grooves M opening in the support surface P is arranged. On the other hand, inside the drive shaft K, an oil supply passage T for pumping up the lubricating oil accumulated in the bottom portion of the casing D is provided, and this oil supply passage T is interposed between the swing links L and a bearing B.
Is opened from the upper surface of the swing link L to the inside of the accommodation chamber E through the gap of, the oil is made to flow into the radial groove M of the thrust bearing S, and good thrust support of the revolution scroll O can be performed by oil lubrication. I am trying.

[0003]

However, in the above, since a relatively large amount of oil enters the inside of the radial groove M under the centrifugal action of the crank portion C in the accommodation chamber E, the thrust bearing S Although preferable for lubrication, on the other hand, the amount of oil overflowing from the outer outlet of the radial groove M also increases, and a large amount of oil flows out to the outer peripheral area of each scroll F, O, so that a large amount of oil flows between the scrolls F, O. There is a problem that a large amount of oil is taken into the working chamber that is defined, oil compression occurs, and the amount of oil that is carried out with the discharge fluid increases, which causes a so-called oil rise problem.

In this case, it is conceivable to reduce the flow passage area of the radial groove M to reduce the amount of oil flowing into the radial groove M from the accommodation chamber E. In this case, however, the support surface P of the thrust bearing S is reduced. In addition, there is a problem in that the oil cannot be sufficiently sprinkled, dust is easily clogged in the radial groove M, and the original good thrust support cannot be performed.

A main object of the present invention is to provide a scroll type fluid machine capable of performing good thrust support, reducing the amount of oil flowing out of the thrust bearing, and reducing oil spillage. .

[0006]

In order to achieve the above main object, first, a pair of scrolls 1 and 2 are disposed inside a casing 10 through a housing 3, and the housing 3 is provided with Crank part 5 provided at the end of the drive shaft 4
And a supporting surface 80 for supporting the back surface of one scroll 2 and a supporting surface 8 on the top surface of the housing 3 which faces the inner peripheral edge of the housing chamber 6.
An annular thrust bearing 8 having a large number of radial grooves 7 opening at 0 is arranged, while an oil supply passage 9 for pumping up the lubricating oil accumulated inside the casing 10 is provided inside the drive shaft 4. In the scroll type fluid machine in which the oil supply passage 9 is opened to the inside of the accommodation chamber 6, at least one midway portion of the radial groove 7 is communicated with the internal space of the casing 10 via the oil return passage 70. .

Secondly, in the first means, the excess oil is returned to the thrust bearing 8 by dispersing the oil along the circumference of the thrust bearing 8 for better thrust support and oil recovery. For this purpose, the plurality of radial grooves 7 are provided with oil return holes 71 communicating with the side opposite to the support surface of the thrust bearing 8, and these oil return holes 71 and the oil return holes 71 are provided in the thrust bearing 8 respectively. And an annular communication groove 72 which communicates with each other on the side opposite to the support surface of the casing 10 and the communication groove 72.
The oil return passage 70 with the communication hole 73 communicating with the internal space of the
Was formed.

Thirdly, in each of the above-mentioned first or second means, the oil flowing out from the outer side outlet portion of the radial groove 7 is temporarily blocked to effectively collect the oil in the oil return passage 70. Let me do it
Housing 3 for better oil return
An annular recess 30 for receiving the thrust bearing 8 is provided on the outer peripheral wall portion of the annular recess 30, and an annular groove 31 for opening the outer side outlet of the radial groove 7 and an outer side of the annular groove 31. The support shaft 80 of the thrust bearing 8 is provided upright, and the annular weir 32 having substantially the same height is provided.

Fourthly, in each of the first and second means described above, in order to allow the oil to smoothly flow into the oil return passage 70, the radial groove 7 is provided around the inlet portion of the oil return passage 70. An oil sump 7a having a size surrounding the oil sump 7a is provided.

[0010]

By the above-mentioned first means, the oil flowing into the radial groove 7 not only tries to flow out from the outer side outlet portion of the radial groove 7, but also the oil return passage opened in at least one radial groove 7. It is collected in the casing 10 via 70. In this case, only opening the oil return passage 70 in the radial groove 7 does not attempt to reduce the flow passage area of the radial groove 7 and reduce the amount of oil flowing in from the storage chamber 6. 7
A sufficient amount of oil can be taken in, and the oil can be smoothly circulated to the support surface 80 of the thrust bearing 8, and good thrust support can be performed. Then, in accordance with the amount of oil collected through the oil return passage 70 opened in the middle of the radial groove 7, the scrolls 1 and 2 are respectively introduced from the outer outlet of the radial groove 7.
It is possible to reduce the amount of oil that flows out to the outer peripheral region of the oil, and thus to reduce the oil rise.

By the second means, the oil return holes 71 are opened in the plurality of radial grooves 7 to perform the oil return. Therefore, the oil return of the surplus oil in the thrust bearing 8 is performed on the circumference of the thrust bearing 8. It is possible to disperse the oil along the circumference of the radial groove 7, and to further reduce the amount of oil flowing out from the outer outlet of the radial groove 7, and to make the oil distribution along the circumference of the thrust bearing 8 uniform. Further, better thrust support and oil recovery can be performed. Moreover, the plurality of radial grooves 7 are not communicated with the casing 10 via independent oil return passages, but the oil return holes 71 extending from the radial grooves 7 are gathered in the annular communication groove 72, and the communication grooves are formed. Since it is opened from 72 to the casing 10 through the communication hole 73, the overall configuration of the oil return passage 70 can be simplified.

By the above-mentioned third means, the oil which is about to flow out from the outer side outlet of the radial groove 7 is blocked by the annular dam 32 and is accumulated in the annular groove 31. Thus, the scrolls 1 and 2 are directly connected to each other by the annular weir 32.
It is possible to reduce the amount of oil flowing out to the outer peripheral region of the oil, and to collect the oil accumulated in the annular groove 31 into the oil return passage 70 opened in the middle of the radial groove 7 and collect it inside the casing 10. , As a whole, each scroll 1,2
It is possible to further reduce the amount of oil flowing into the outer peripheral region of the. In this case, the annular weir portion 32 is formed at substantially the same height as the supporting surface 80 of the thrust bearing 8, but the scroll 2 received by the thrust bearing 8 floats on the outer peripheral side due to flexural deformation, so that the scroll 2 A contact accident does not occur between the back surface and the top surface of the annular weir portion 32, but rather, the annular weir portion 32 is positively made substantially flush with the support surface 80 of the thrust bearing 8 so that the radial groove 7 is formed. Annular groove 31 and scroll 1, which will be the exit of
It is possible to minimize the gap between the second outer peripheral region and the outer peripheral region, and to effectively reduce the amount of spilled oil.

By the above-mentioned fourth means, the surplus oil of the thrust bearing 8 can be smoothly introduced into the oil return passage 70 through the oil sump portion 7a, and the surplus oil of the thrust bearing 8 can be recovered well. it can.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 shows a scroll type fluid machine using a refrigerant compressor, in which a fixed scroll 1 and an orbiting scroll 2 are disposed above a sealed casing 10 through a housing 3 and below the scroll. Further, the motors 40 each having the drive shaft 4 directly connected thereto are arranged. The housing 3 is provided with a housing chamber 6 which is provided at an end portion of the drive shaft 4 and which houses a crank portion 5 having an eccentric hole 51 into which a boss portion 21 protruding from the rear surface of the revolution scroll 2 is fitted. Further, an annular recess 30 is provided on the top surface of the housing 3 whose inner peripheral edge faces the accommodation chamber 6, and an annular thrust bearing 8 having a support surface 80 for supporting the back surface of the revolution scroll 2 is provided. There is. On the other hand, inside the drive shaft 4, there is provided an oil supply passage 9 for carrying oil to be pumped from an oil reservoir at the bottom through an oil pump. The oil supply passage 9 is provided in the bearing gaps of the upper main bearing 91 and the crank portion bearing 92. It is opened to the inside of the accommodation chamber 6 via.

The low-pressure gas sucked into the casing 10 from the suction pipe 11 is taken into the inner working chamber 13 from the outer peripheral regions 12 of the scrolls 1 and 2, and the compressed high-pressure gas is fed to the center of the fixed scroll 1. It is taken out from the discharge port 14 provided in the inside of the high-pressure chamber 16 defined by the partition wall 15 to the outside through the discharge pipe 17.

The oil accumulated at the bottom of the housing chamber 6 passes through the oil discharge passage 33 opening to the side of the housing 3 to the casing 1.
The oil collected in the high pressure chamber 16 is also collected in the casing 10 via the oil return pipe 18 inserted into the through hole 34 formed in the fixed scroll 1 and the housing 3.

With the above construction, as clearly shown in FIG. 1, the thrust bearing 8 has a large number of radiations, for example, three in a quarter arc portion opening in the support surface 80 as shown in FIG. A groove 7 is provided, and as shown in FIG. 2, at least one intermediate portion of the radial groove 7 is formed so as to penetrate the thrust bearing 8 in the axial direction and a second passage 70b provided in the housing 3. Oil return passage 70 composed of
Through the oil drain passage 33 leading to the internal space of the casing 10. Radial groove 7 that opens the oil return passage 7
Is provided with an oil sump portion 7a surrounding the inlet of the first passage 70a and having a diameter larger than the diameter of the first passage 70a.

Further, on the outer peripheral wall of the annular recess 30 in the housing 3, an annular groove 31 for opening the outer side outlet of the radial groove 7 and an outer side of the annular groove 31 are erected, and thrust bearings are provided. 8 and the annular weir 32 having the same height as the supporting surface 80.

With the above structure, the oil that has flowed into the radial groove 7 not only tries to flow out from the outer side outlet of the radial groove 7, but also from the middle of the radial groove 7 via the oil sump portion 7a. The oil smoothly flows into the oil return passage 70, and is recovered inside the casing 10 through the oil return passage 70 and the oil discharge passage 33. In this case, the oil return passage 70 is only opened in the radial groove 7, and the flow passage area of the radial groove 7 is not reduced to reduce the amount of oil flowing in from the storage chamber 6.
A sufficient amount of oil can be taken in, and the oil can be smoothly circulated to the support surface 80 of the thrust bearing 8. Then, in proportion to the amount of oil recovered through the oil return passage 70 opened in the middle of the radial groove 7, the oil flowing out from the outer outlet of the radial groove 7 to the outer peripheral region 12 of each scroll 1, 2. The amount can be reduced, and the oil rise can be reduced.

Moreover, the oil that is about to flow out from the outlet on the outer side of the radial groove 7 is blocked by the annular dam 32,
The amount of oil flowing out to the outer peripheral areas of the scrolls 1 and 2 can be reduced directly by the annular weir 32, and the oil accumulated in the annular groove 31 can be collected in the middle of the radial groove 7. It can be collected in the casing 10 by flowing into the oil return passage 70 opened in the portion, and as a whole, the amount of oil flowing out to the outer peripheral region 12 of each scroll 1, 2 can be further reduced. . In addition, the annular weir 32 has the same height as the support surface 80 of the thrust bearing 8, but as shown by the imaginary line in FIG. 2, the reaction force from the working chamber 13 side and the orbiting scroll 2 which bends due to its own weight. It is possible to avoid a contact accident between the outer peripheral back surface and the top surface of the annular weir portion 32, and by positively setting the annular weir portion 32 at the same height as the supporting surface 80, the distance between the end surfaces is increased. The gap can be minimized and the amount of oil spilled can be effectively reduced. Further, the annular weir 32 is attached to the thrust support surface 8
Since the height is the same as 0, these annular weirs 32
It is possible to obtain an advantage that the top surface and the supporting surface 80 of the thrust bearing 8 can be cut at the same time.

By the way, in the above embodiment, one oil return passage 70 is opened in one radial groove 7 so that the oil is returned from one place. However, as shown in FIGS. For example, the oil return holes 71 communicating with the anti-bearing surface side of the thrust bearing 8 are opened with respect to the six radial grooves 7 that are skipped, and these oil return holes 71 and the anti-bearing surface side of the thrust bearing 8 are provided. The oil return passage 70 is formed by an annular communication groove 72 that is provided in the oil communication hole 71 and that communicates the oil return holes 71 with each other, and a communication hole 73 that communicates the communication groove 72 with the drain oil passage 33 that communicates with the internal space of the casing 10. Then, the oil may be returned from a plurality of locations along the circumference of the thrust bearing 8.

In this case, the excess oil in the thrust bearing 8 can be returned by being dispersed along the circumference of the thrust bearing 8 and flow out from the outer outlet of the radial groove 7. The amount of oil can be further reduced, the oil distribution along the circumference of the thrust bearing 8 can be made uniform, and more favorable thrust support and oil recovery can be performed. Moreover, instead of communicating the plurality of radial grooves 7 with the casing 10 via independent oil return passages, the oil return holes 71 extending from the respective radial grooves 7 are gathered in the annular communication groove 72, and the communication grooves are formed. Since it is opened from 72 to the casing 10 through the communication hole 73, the entire structure of the oil return passage 70 can be simplified.

The annular groove 72 is provided on the side opposite to the supporting surface of the thrust bearing 8 as shown in FIG. 5, and as shown in FIG. 6, the housing 3 is in contact with the side opposite to the supporting surface of the thrust bearing 8.
It may be provided in the annular recess 30. In this case as well, the same operational effect is obtained.

Further, in each of the above-mentioned embodiments, the second passage 70b and the communication hole 73 constituting the outlet side of the oil return passage 70 are straightly extended in the axial direction and joined to the oil discharge passage 33. 7, the axial passage 73a and the radial passage 73
b may be provided so as to join the through hole 34 through which the oil return pipe 18 is inserted, and in this case also, the same effect as the above can be obtained.

[0025]

As described above, according to the first aspect of the present invention, the intermediate portion of at least one radial groove 7 provided in the thrust bearing 8 is provided with the casing 10 through the oil return passage 70.
Since the scroll 2 is communicated with the inner space of the scroll 2, good thrust support of the scroll 2 can be achieved by oil lubrication, and excess oil of the thrust bearing 8 can be recovered through the oil return passage 70. It is possible to reduce the amount of oil that flows out to the outer peripheral regions of the scrolls 1 and 2, and it is possible to reduce the oil spillage.

According to the second aspect of the present invention, the oil return holes 71 opening in the plurality of radial grooves 7, the communication groove 72 for communicating these with each other, and the communication hole 73 for communicating with the casing 10 are simple. With such a configuration, the excess oil in the thrust bearing 8 can be returned by being dispersed along the circumference of the thrust bearing 8, and the amount of oil flowing out from the outer side outlet of the radial groove 7 can be further increased. In addition to being able to reduce the amount of oil, the oil distribution along the circumference of the thrust bearing 8 can be made uniform, and more favorable thrust support and oil recovery can be performed.

According to the third aspect of the present invention, by the annular groove 31 and the annular weir 32 at the outer outlet of the radial groove 7,
The oil flowing out from the radial groove 7 can be temporarily blocked, and the oil can be effectively recovered in the oil return passage 70, so that better oil return can be performed.

According to the fourth aspect of the invention, the surplus oil of the thrust bearing 8 can be smoothly introduced into the oil return passage 70 through the oil sump portion 7a, and the surplus oil of the thrust bearing 8 can be recovered well. can do.

[Brief description of drawings]

FIG. 1 is a plan view of an essential part showing a first embodiment of a scroll type fluid machine according to the present invention.

FIG. 2 is a sectional view taken along line X, X of FIG.

FIG. 3 is an upper sectional view of the scroll type fluid machine.

FIG. 4 is a plan view of an essential part showing the second embodiment.

5 is a cross-sectional view taken along line Y, Y of FIG.

FIG. 6 is a cross-sectional view of a main part showing the third embodiment.

FIG. 7 is a sectional view of an essential part showing the fourth embodiment.

FIG. 8 is an upper sectional view of a conventional scroll type fluid machine.

FIG. 9 is a plan view of a main part of a conventional thrust bearing.

[Explanation of symbols]

1; scroll (fixed scroll), 2; scroll (revolution scroll), 3; housing, 30; annular recess, 31; annular groove, 32; annular weir, 4; drive shaft,
5; Crank part, 6; Storage chamber, 7; Radial groove, 7a; Oil sump part, 70; Oil return passage, 71; Oil return hole, 72; Communication groove, 73; Communication hole, 8; Thrust bearing, 80; Support surface,
9: Oil supply passage, 10: Casing

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location F04C 29/02 321 A 6907-3H 361 A 6907-3H

Claims (4)

[Claims] 1. A pair of scrolls 1 and 2 are disposed inside a casing 10 through a housing 3, and a housing chamber 6 for housing a crank portion 5 provided at an end portion of a drive shaft 4 is provided in the housing 3. The support surface 80 that supports the back surface of one scroll 2 and a large number of the radiation grooves 7 that are open to the support surface 80 are provided on the top surface of the housing 3 that faces the inner peripheral edge of the housing chamber 6. While the annular thrust bearing 8 is arranged, an oil supply passage 9 for pumping up the lubricating oil accumulated in the casing 10 is provided inside the drive shaft 4, and the oil supply passage 9 is provided inside the accommodating chamber 6. In the open scroll type fluid machine, at least one midway portion of the radial groove 7 is communicated with an internal space of the casing 10 through an oil return passage 70. Body machine. 2. An oil return hole 71 communicating with a side opposite to the support surface of the thrust bearing 8 is opened in each of the plurality of radial grooves 7, and each oil return hole 71 and each oil return hole 71 are formed in the thrust bearing 8.
Communication groove 7 for communicating with each other on the side opposite to the support surface of
The scroll type fluid machine according to claim 1, wherein the oil return passage 70 is formed by 2 and a communication hole 73 that communicates the communication groove 72 with the internal space of the casing 10. 3. A housing 3 is provided with an annular recess 30 for receiving the thrust bearing 8, and an annular groove 31 for opening an outer side outlet of the radial groove 7 in an outer peripheral wall portion of the annular recess 30.
And an annular weir 32 that stands upright on the outer side of the annular groove 31 and has substantially the same height as the supporting surface 80 of the thrust bearing 8.
The scroll type fluid machine according to claim 1 or 2, further comprising: 4. The radial groove 7 is provided with an oil sump 7a having a size surrounding the inlet of the oil return passage 70.
Alternatively, the scroll type fluid machine according to claim 2.