WO2013084486A1

WO2013084486A1 - Scroll compressor

Info

Publication number: WO2013084486A1
Application number: PCT/JP2012/007793
Authority: WO
Inventors: 山田　定幸; 阪井　学; 岳史今西; 淳作田
Original assignee: パナソニック株式会社
Priority date: 2011-12-09
Filing date: 2012-12-05
Publication date: 2013-06-13
Also published as: JP2015038323A

Abstract

The axial cross-sectional area (B) of a concave portion (26b) is greater than a first channel area (A) at a portion where one opening of the channel and the concave portion overlap, and a second channel area (C) where the concave portion (26b) opens into a compression chamber, whereby the constricting of the channel area to cause resistance is eliminated. Therefore, the pressure of a back-pressure chamber (22) is prevented from exceeding the pressure of a communicating compression chamber (10), and the force exerted on the sliding surfaces of a fixed scroll (11) and a turning scroll (12) is prevented from increasing, improving reliability, particularly during high-speed and high-load operation.

Description

Scroll compressor

The present invention relates to a scroll compressor used for a cooling device such as an air conditioning air conditioner or a refrigerator, or a heat pump type hot water supply device.

Conventionally, various scroll compressors of this type have been filed by many manufacturers regarding similar compressors, and various compressors are actually used as compressors for home room air conditioners and refrigerators. Has been. Recently, it has also begun to be used as a compressor for automobile air conditioners.

Further, in order to lubricate the compression mechanism portion of these compressors, for example, as disclosed in Patent Document 1, a back pressure chamber oil supply path and a compression chamber oil supply path formed in the fixed scroll and the orbiting scroll are installed. By doing so, there is a method of always refueling based on a predetermined restriction.

International Publication No. 2010/087179

In the conventional configuration, the compression chamber oil supply path includes a passage formed inside the orbiting scroll and a recess formed in the end plate of the fixed scroll. In one opening of this passage, the back pressure chamber and the compression chamber are intermittently communicated by the concave portions periodically overlapping with the orbiting motion of the orbiting scroll. However, at the time of this communication, one of the passage area where one opening of this passage and the concave portion overlap, the cross-sectional area of the concave portion, and the passage area of the portion where the concave portion opens into the compression chamber is reduced to become a resistance. There is. As a result, the pressure in the back pressure chamber becomes abnormally higher than the pressure in the compression chamber communicating with the pressure chamber, and as an example, the pressure becomes unstable.

The present invention solves the conventional problems, and aims to improve the reliability particularly at high speed and high load operation by stabilizing the pressure in the back pressure chamber.

According to a first aspect of the present invention, there is provided a scroll compressor comprising: a motor and a compression mechanism portion housed in a container; and the compression mechanism portion combined with the orbiting scroll in which a spiral wrap is formed upright on an end plate and the orbiting scroll. And a fixed scroll formed with a spiral wrap standing upright on the end plate, and a main bearing member for disposing the orbiting scroll between the fixed scroll and holding a seal member, and the orbiting scroll and the fixed scroll A compression chamber is formed between the scroll and the scroll member, and the seal member is disposed on the back of the orbiting scroll. The seal member divides the inside of the seal member into a high pressure region and the outside of the seal member into a back pressure chamber. A back pressure chamber oil supply passage for supplying lubricating oil from the high pressure region to the back pressure chamber, and supplying the lubricating oil from the back pressure chamber to the compression chamber The compression chamber oil supply path is provided, and one opening of the back pressure chamber oil supply path is moved back and forth through the seal member, whereby the high pressure region and the back pressure chamber are intermittently communicated, and the compression chamber oil supply path is It is composed of a passage formed inside the orbiting scroll and a recess formed in the end plate of the fixed scroll, and one opening of the passage periodically overlaps the recess according to the orbiting motion of the orbiting scroll. Thus, in the scroll compressor in which the back pressure chamber and the compression chamber communicate intermittently, the diameter of the recess is determined by the first passage area generated by the overlap of the one opening of the passage and the recess. The axial cross-sectional area determined by the depth is increased, and the axial cross-sectional area is made larger than the second passage area generated when the recess opens into the compression chamber. As a result, the passage area is reduced so that there is no resistance and the pressure in the back pressure chamber does not become abnormally higher than the pressure in the compression chamber that communicates, and the force applied to the sliding surfaces of the fixed scroll and the orbiting scroll And the reliability at high speed and high load operation is improved.

According to a second aspect of the present invention, in the scroll compressor according to the first aspect, the first passage area is 0.9 to 1.1 times the second passage area at a position where the first passage area is maximized. It is characterized by that. With this configuration, since the passage resistance can be minimized, the pressure in the back pressure chamber is stabilized and the reliability is improved.

A third invention is characterized in that, in the scroll compressor according to the first or second invention, an opening diameter of the recess is smaller than a thickness of the wrap of the orbiting scroll. With this configuration, the pressure in the back pressure chamber is further stabilized.

The fourth invention is characterized in that, in the scroll compressor according to any one of the first to third inventions, a tip seal is not provided at the tip of the wrap of the orbiting scroll. With this configuration, both high efficiency and cost reduction can be realized.

The fifth invention is characterized in that in the scroll compressor according to any one of the first to fourth inventions, the recess is provided in the compression chamber after the working fluid is closed.

In the scroll compressor of the present invention, the passage area is reduced and the resistance is reduced by making the cross-sectional area of the recess larger than the passage area where the one opening of the passage overlaps with the recess and the passage area where the recess opens into the compression chamber. It will never be. Therefore, the pressure in the back pressure chamber does not become abnormally higher than the pressure in the compression chamber that communicates, the force applied to the sliding surface of the fixed scroll and the orbiting scroll does not increase, especially during high speed and high load operation Will improve.

Sectional drawing of the scroll compressor in Embodiment 1 of this invention (A) Main part enlarged sectional view in case one opening of back pressure chamber oil supply path in compression mechanism part of same scroll compressor is located on high pressure region side with respect to seal member (b) Compression mechanism of same scroll compressor The principal part expanded sectional view when one opening of the back pressure chamber oil supply path | route in a part is located in the outer side of a sealing member Cross-sectional view of the main part showing a state in which the orbiting scroll and the fixed scroll of the scroll compressor are combined. (A) Cross-sectional view showing the compression chamber side opening of the scroll compressor and the axial direction thereof (b) Plan view of the compression chamber side opening seen from the recess of the scroll compressor (c) The recess is shown in FIG. Cross section when viewed in the direction of the arrow The figure explaining the pressure change of the compression chamber of the scroll compressor

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Mounting leg 3 Main body casing 3a End wall 4 Compression mechanism part 5 Motor 6 Liquid storage part 7 Lubricating oil 8 Suction port 9 Discharge port 10 Compression chamber 11 Fixed scroll

11a End plate

11b Spiral wrap 12 Turning scroll 12a End plate 12b Spiral wrap 12c Cylindrical boss 13 Pump 14 Drive shaft 14a Eccentric shaft 15 Oil supply path 16 Suction port 17 Bolt 18 Bolt 19 Tip seal 21 High pressure region 21a First high pressure region 21b Second high pressure region 22 Back pressure Chamber 24 Seal member 25 Back pressure chamber lubrication path 25a First back pressure chamber lubrication path 25b Second back pressure chamber lubrication path 25c Open 26 Compression chamber lubrication path 26a Path 26b Recess 26c Compression chamber side opening 30 Bush 31 Discharge port 31a Reed valve 41 Sub rolling bearing 42 Main rolling bearing 43 Eccentric rolling Ridge bearing 43a Inner ring 43b Outer ring 51 Main bearing member 52 Lid body 53 Pump chamber 54 Suction passage 57 Oldham ring 62 Discharge chamber 63 Communication passage 80 Subcasing 80a End wall A First passage area B Axial sectional area C Second passage area

A scroll compressor according to a first aspect of the present invention includes a back pressure chamber oil supply passage for supplying lubricant from a high pressure region to a back pressure chamber, and a compression chamber oil supply passage for supplying lubricant from the back pressure chamber to the compression chamber. One opening of the chamber refueling path communicates with the seal member so that the high pressure region and the back pressure chamber are intermittently communicated, and the compression chamber refueling path is a passage formed inside the orbiting scroll, and a fixed scroll end plate This is a scroll compressor in which the back pressure chamber and the compression chamber are intermittently communicated by one of the passages periodically overlapping the recess in accordance with the orbiting motion of the orbiting scroll. The second passage area generated by opening the recess into the compression chamber by increasing the axial cross-sectional area determined by the diameter and depth of the recess from the first passage area caused by the overlap of one opening of the passage and the recess. More axial section It is those that were big. According to this configuration, since the passage area is small and does not become resistance, the pressure of the back pressure chamber does not become abnormally higher than the pressure of the compression chamber communicating with the sliding surface of the fixed scroll and the orbiting scroll. Therefore, the reliability at high speed and high load operation is improved.

The second aspect of the invention is particularly the scroll compressor of the first aspect, wherein the first passage area is 0.9 to 1.1 times the second passage area at the position where the first passage area is maximized. It is. According to this configuration, both the passage areas are approximately equal and maximized, and the passage resistance can be minimized, so that the pressure in the back pressure chamber is stabilized and the reliability is improved.

In the third aspect of the invention, in particular, in the scroll compressor of the first aspect or the second aspect, the opening diameter of the recess is made smaller than the thickness of the orbiting scroll wrap. According to this configuration, the number of compression chambers through which one opening of the passage communicates is limited to one, the pressure in the back pressure chamber is stabilized, and the reliability is improved under all operating conditions.

The fourth invention is a scroll compressor according to the first to third inventions, in which a tip seal is not provided at the tip of the orbiting scroll wrap. According to this configuration, even if the gap between the wrap tips is reduced, the passage area is reduced and does not become resistance, so that the pressure in the back pressure chamber is stabilized and high efficiency can be realized.

In the fifth aspect of the invention, in particular, in the scroll compressor according to the first to fourth aspects of the invention, the recess is provided in the compression chamber after the working fluid is closed. According to this configuration, it is possible to prevent a so-called tilting phenomenon in which the ability is reduced when the orbiting scroll is separated from the fixed scroll.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
1 is a cross-sectional view of a scroll compressor according to an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of a main part of the compression mechanism portion of FIG. 1, and FIG. 3 is a combination of a turning scroll and a fixed scroll of the scroll compressor. FIG. 4 is a view showing a communication state of a compression chamber oil supply path of the scroll compressor.

FIG. 1 shows a horizontal scroll compressor installed sideways by a mounting leg 2 around the body of the scroll compressor 1. The scroll compressor 1 includes a liquid storage unit 6 in which a compression mechanism unit 4 and a motor 5 for driving the compression mechanism unit 4 and a motor 5 for driving the compression mechanism unit 4 are stored in a main body casing 3. The motor 5 is driven by a motor drive circuit unit (not shown). The working fluid to be handled is a gas refrigerant, and the lubricating oil 7 is used to lubricate each sliding portion and is used as a seal for the sliding portion of the compression mechanism portion 4 and is compatible with the refrigerant. However, the present invention is not limited to these. Basically, a compression mechanism part 4 that sucks, compresses and discharges the working fluid, a motor 5 that drives the compression mechanism part 4, and a liquid that is used for lubrication of each sliding part including the compression mechanism part 4 is stored. The liquid storage unit 6 is built in the main body casing 3, and the scroll compressor 1 that drives the motor 5 by the motor drive circuit unit may be used, and is not limited to the following description.

The compression mechanism unit 4 includes an orbiting scroll 12 formed by standing upright a spiral wrap 12b on an end plate 12a, and a fixed scroll 11 formed by combining the orbiting scroll 12 with an upright spiral wrap 11b on an end plate 11a, The orbiting scroll 12 is disposed between the fixed scroll 11 and the main bearing member 51 that holds the seal member 24. A tip seal 19 is disposed at the wrap tip of the orbiting scroll 12.
The fixed scroll 11 has a suction port 16 at the outer peripheral portion of the end plate 11a and a discharge port 31 at the center of the end plate 11a. The orbiting scroll 12 has a cylindrical boss 12c formed on the back surface.
An eccentric shaft 14 a is integrally formed at one end of the drive shaft 14, and the eccentric shaft 14 a is supported by a cylindrical boss portion 12 c via an eccentric rolling bearing 43. The eccentric shaft 14a is fitted with a bush 30. And the inner ring | wheel 43a of the eccentric rolling bearing 43 is fitted by the bush 30, and the outer ring | wheel 43b of the eccentric rolling bearing 43 is loosely fitted by the cylindrical boss | hub part 12c with a slight clearance. One end side of the drive shaft 14 is supported by a main bearing member 51 via a main rolling bearing 42.

The seal member 24 is disposed on the back surface of the end plate 12 a of the orbiting scroll 12. The back surface of the end plate 12 a of the orbiting scroll 12 is partitioned by the seal member 24 so that the inside of the seal member 24 forms a high pressure region 21 and the outside of the seal member 24 forms a back pressure chamber 22.
The high-pressure region 21 includes the first high-pressure region 21a surrounded by the cylindrical boss portion 12c and the eccentric rolling bearing 43, the main bearing member 51, the cylindrical boss portion 12c, the eccentric rolling bearing 43, and the main rolling bearing 42. The second high-pressure region 21b surrounded by The lower part of the second high-pressure region 21b constitutes an oil sump.
A back pressure chamber oil supply passage 25 for supplying the lubricating oil 7 from the high pressure region 21 to the back pressure chamber 22 is formed in the end plate 12 a of the orbiting scroll 12. The back pressure chamber refueling path 25 includes a first back pressure chamber refueling path 25a that communicates with the first high pressure region 21a, and a second back pressure chamber refueling path 25b through which one opening 25c travels the seal member 24. The first back pressure chamber oil supply path 25a and the second back pressure chamber oil supply path 25b are in communication with each other.

The compression chamber oil supply path 26 includes a passage 26 a formed inside the orbiting scroll 12 and a recess 26 b formed on the bottom surface of the end plate 11 a of the fixed scroll 11, and lubricates the compression chamber 10 from the back pressure chamber 22. Supply oil 7. The compression chamber side opening 26c of the passage 26a is formed at the tip of the spiral wrap 12b of the orbiting scroll 12, and periodically overlaps the recess 26b in accordance with the orbiting motion of the orbiting scroll 12, so that the back pressure chamber 22 and The compression chamber 10 communicates intermittently.
The compression chamber 10 is formed by meshing the spiral wrap 11 b of the fixed scroll 11 and the spiral wrap 12 b of the orbiting scroll 12, and moves when the orbiting scroll 12 is orbited relative to the fixed scroll 11. The volume is changed accordingly. The refrigerant gas returning from the external cycle is sucked into the compression chamber 10 from the suction port 16, and the refrigerant gas compressed in the compression chamber 10 is discharged from the discharge port 31 to the discharge chamber 62.
The main casing 3 is provided with a discharge port 9 for discharging compressed refrigerant gas, and the sub casing 80 is provided with a suction port 8 for sucking compressed refrigerant gas. The main body casing 3 and the sub casing 80 constitute a container.

Furthermore, the scroll compressor 1 arranges a main bearing member 51 having a pump 13, a sub rolling bearing 41, a motor 5, and a main rolling bearing 42 in this order from the one end wall 3 a side in the axial direction in the main body casing 3. It is. The pump 13 is accommodated from the outer surface of the end wall 3 a and is fitted and fixed by a lid 52. In addition, a pump chamber 53 is formed inside the lid 52, and the pump chamber 53 communicates with the liquid storage unit 6 through a suction passage 54. The auxiliary rolling bearing 41 is supported by the end wall 3 a and pivotally supports the side of the drive shaft 14 connected to the pump 13. The motor 5 includes a stator 5a and a rotor 5b, and drives the drive shaft 14 to rotate. The stator 5 a is fixed to the inner periphery of the main casing 3 by shrink fitting or the like, and the rotor 5 b is fixed to the drive shaft 14.
The main bearing member 51 is fixed to the inner periphery of the sub casing 80 with bolts 17 and the like, and the compression mechanism portion 4 side of the drive shaft 14 is supported by the main rolling bearing 42. The fixed scroll 11 is attached to the outer surface of the main bearing member 51 with a bolt or the like (not shown), and the orbiting scroll 12 is sandwiched between the main bearing member 51 and the fixed scroll 11. An Oldham ring 57 is provided between the main bearing member 51 and the orbiting scroll 12 to prevent the orbiting scroll 12 from rotating and to orbit.

The exposed portion of the compression mechanism 4 from the sub casing 80 is covered with the main casing 3. The sub casing 80 forms an end wall 80a on the side opposite to the end wall 3a in the axial direction. The main casing 3 and the sub casing 80 are fixed with bolts 18 with their openings facing each other. The compression mechanism unit 4 is located between the suction port 8 of the sub casing 80 and the discharge port 9 of the main casing 3, and the suction port 16 of the fixed scroll 11 is connected to the suction port 8 of the sub casing 80. The discharge port 31 is connected to the discharge chamber 62 through a reed valve 31a. The discharge chamber 62 communicates with the space on the motor 5 side through a communication passage 63 formed in the fixed scroll 11 and the main bearing member 51. The communication passage 63 may be formed between the fixed scroll 11 and the main bearing member 51 and the main body casing 3.
The motor 5 is driven by the motor drive circuit unit, and rotates the compression mechanism unit 4 via the drive shaft 14 and drives the pump 13. At this time, the compression mechanism section 4 is supplied with the lubricating oil 7 of the liquid storage section 6 by the pump 13 and receives lubrication and sealing action. The refrigerant gas discharged into the discharge chamber 62 passes through the motor 5 from the communication passage 63 and is discharged from the discharge port 9 of the main body casing 3 while cooling the motor 5. Lubricating oil 7 contained in the refrigerant gas in the container is separated from the refrigerant gas by collision or squeezing action, and lubricates the sub rolling bearing 41.
The lubricating oil 7 stored in the liquid storage part 6 of the main casing 3 is supplied to the oil supply passage 15 formed in the drive shaft 14 by driving the pump 13 by the drive shaft 14. The outlet of the oil supply passage 15 is formed at the end of the eccentric shaft 14a. Note that the supply of the lubricating oil 7 to the oil supply passage 15 may use the differential pressure in the main casing 3 instead of driving the pump 13.

Here, the flow of the lubricating oil 7 in the compression mechanism 4 will be described with reference to FIG.
With the turning driving of the turning scroll 12, the lubricating oil 7 from the oil supply passage 15 is supplied to the first high pressure region 21a.
In the state of FIG. 2A, one opening 25 c of the back pressure chamber oil supply path 25 is located on the high pressure region 21 side with respect to the seal member 24, and the lubricating oil 7 is not supplied to the back pressure chamber 22.
In this state, a part of the lubricating oil 7 supplied to the first high pressure region 21 a is supplied to the second high pressure region 21 b via the eccentric rolling bearing 43. Further, another part of the lubricating oil 7 supplied to the first high-pressure region 21a has a first opening 25c of the second back pressure chamber oil supply passage 25b positioned inside the seal member 24, so that the first The high pressure region 21a is supplied to the second high pressure region 21b. The lubricating oil 7 supplied to the second high pressure region 21b in this way flows out to the space on the motor 5 side through the main rolling bearing 42 and is recovered to the liquid storage unit 6.
In the state of FIG. 2 (b), one opening 25c of the back pressure chamber oil supply passage 25 is positioned outside the seal member 24, so that a part of the lubricating oil 7 supplied to the first high pressure region 21a is back. It is supplied to the pressure chamber 22 and backs up the back pressure of the orbiting scroll 12.
Further, in the state of FIG. 2A, the lubricating oil 7 supplied to the back pressure chamber 22 flows from the back pressure chamber 22 to the compression chamber side opening 26 c of the compression chamber oil supply path 26 and the bottom surface of the end plate 11 a of the fixed scroll 11. Is supplied to the compression chamber 10 by communication with the recess 26 b formed in the above, and seals and lubricates between the fixed scroll 11 and the orbiting scroll 12. As shown in FIG. 2B, the lubricating oil 7 is not supplied to the compression chamber 10 when the compression chamber side opening 26c and the recess 26b are not in communication with each other.

FIGS. 3A, 3 </ b> B, 3 </ b> C, and 3 </ b> D show states in which the phase of the orbiting scroll 12 with respect to the fixed scroll 11 is shifted by 90 degrees.
In addition, as shown to a figure, the recessed part 26b is provided in the compression chamber 10a after closing the refrigerant gas which is a working fluid, and is not provided in the compression chamber 10b of the state before closing refrigerant gas. In other words, the compression chamber 10 communicated with the back pressure chamber 22 via the compression chamber oil supply passage 26 is the compression chamber 10a after the working fluid is closed, so that the orbiting scroll 12 can be separated from the fixed scroll 11. This can prevent a so-called tilting phenomenon that lowers the temperature. Even if tilting occurs, the pressure in the compression chamber 10 can be guided to the back pressure chamber 22, so that early return to normal operation is possible.
In the state of FIG. 3D, the compression chamber side opening 26 c overlaps the recess 26 b, whereby the lubricating oil 7 is supplied from the back pressure chamber 22 to the compression chamber 10 through the compression chamber oil supply path 26.
On the other hand, in the states of FIGS. 3A, 3B, and 3C, the compression chamber side opening 26c does not overlap the recess 26b, so that the lubricating oil 7 is supplied from the back pressure chamber 22 to the compression chamber 10. There is no.

Moreover, the compression chamber oil supply path 26 is made into a spiral wrap by making the opening diameter of the recess 26b formed on the bottom surface of the end plate 11a of the fixed scroll 11 of the present embodiment smaller than the thickness of the spiral wrap 12b. It communicates only with the compression chamber 10aB formed inside 12b.
On the other hand, when the opening diameter of the recess 26b is larger than the thickness of the spiral wrap 12b, the compression chamber oil supply path 26 is formed outside the compression chamber 10aB and the spiral wrap 12b formed inside the spiral wrap 12b. It communicates with both of the compression chambers 10aA.

FIG. 4 shows a communication state at a position where the first passage area is maximized due to the overlap between the compression chamber side opening 26 c of the compression chamber oil supply passage 26 and the recess 26 b formed on the bottom surface of the end plate 11 a of the fixed scroll 11. ing. 4A is an axial sectional view of the compression chamber side opening 26c and the recess 26b, FIG. 4B is a plan view of the compression chamber side opening 26c viewed from the recess 26b, and FIG. 4C is FIG. It is sectional drawing of the recessed part 26b when it sees in the direction of the arrow of ().
As shown in FIG. 4A, the lubricating oil 7 is supplied from the compression chamber side opening 26c to the compression chamber 10 through the recess 26b. 4B and 4C, the first passage area generated by the overlap between the compression chamber side opening 26c and the recess 26b is A, the axial sectional area determined by the diameter and depth of the recess 26b is B, and the recess The second passage area generated by opening the b into the compression chamber 10 is C. Further, B> A and B> C.

According to this configuration, in the oil supply path of the lubricating oil 7 from the compression chamber oil supply path 26 to the compression chamber 10 through the recess 26b from the compression chamber side opening 26c, the communication area is reduced in the middle and resistance does not occur. The lubricating oil 7 is stably supplied to the compression chamber 10. Therefore, the pressure of the back pressure chamber 22 does not become abnormally higher than the pressure of the compression chamber 10 with which the back pressure chamber 22 communicates, and the force applied to the sliding surfaces of the fixed scroll 11 and the orbiting scroll 12 does not increase. Especially, reliability at high speed and high load operation is improved.
Further, by setting the first passage area A (A / C) to 0.9 to 1.1 times the second passage area C, the first passage area A and the second passage area C are substantially equivalent passage areas. In particular, one area is not reduced. Accordingly, the passage resistance can be minimized, so that the pressure in the back pressure chamber 22 is stabilized and the reliability is improved.
For example, when the first passage area A (A / C) with respect to the second passage area C is less than 0.9, the first passage area A is reduced and becomes resistance, and the pressure in the back pressure chamber 22 becomes abnormally high. Sometimes. On the other hand, when the first passage area A (A / C) with respect to the second passage area C exceeds 1.1, the second passage area C is reduced to become resistance and the pressure in the back pressure chamber 22 becomes abnormally high. Sometimes. In either case, the reliability decreases.

FIG. 5 is a view showing a pressure change in the compression chamber 10. 5, the pressure change in the inner compression chamber 10aB of the spiral wrap 12b of the orbiting scroll 12 is indicated by a solid line, and the pressure change in the outer compression chamber 10aA of the spiral wrap 12b is indicated by a broken line.
As described above, when the opening diameter of the concave portion 26b formed on the bottom surface of the end plate 11a of the fixed scroll 11 is smaller than the thickness of the spiral wrap 12b, the compression chamber oil supply path 26 is located inside the spiral wrap 12b. It communicates only with the compression chamber 10aB to be formed. The pressure in the compression chamber at this time is B. Therefore, the pressure in the back pressure chamber 22 is stabilized.

On the other hand, when the opening diameter of the recess 26b is larger than the thickness of the spiral wrap 12b, the compression chamber oil supply path 26 communicates with the compression chamber 10aB formed inside the spiral wrap 12b. The pressure in the compression chamber at this time is B. Moreover, it communicates with the compression chamber 10aA formed outside the spiral wrap 12b, and the pressure in the compression chamber at this time is A. In this case, since the back pressure chamber 22 communicates with two different compression chambers 10aB and 10aA, the pressure in the back pressure chamber 22 varies between the pressure B and the pressure A in FIG. 5 and becomes unstable.
From the above, by making the opening diameter of the recess 26b smaller than the thickness of the spiral wrap 12b, the compression chamber with which the compression chamber oil supply path 26 communicates is limited to one. As a result, the compression chamber oil supply passage 26 is not alternately switched to and communicated with a plurality of compression chambers, the pressure in the back pressure chamber 22 is stabilized, and the reliability is improved under all operating conditions.

Further, the cost can be reduced by eliminating the tip seal 19 of the present embodiment, but there is a possibility that a gap is formed at the tip of the spiral wrap 12b of the orbiting scroll 12 and the sealing performance is lowered. Accordingly, if the clearance between the ends of the spiral wrap 12b of the orbiting scroll 12 is reduced, the sealing performance is improved. However, when the axial cross-sectional area B of the recess 26b is small, the passage is constricted to become a resistance and the pressure in the back pressure chamber 22 is abnormal. There is a possibility of rising.
In the present embodiment, since the axial cross-sectional area B of the recess 26b is larger than the first passage area A and the second passage area C, the passage is not restricted even if the tip clearance of the spiral wrap 12b is reduced. Therefore, the lubricating oil 7 is stably supplied to the compression chamber 10, and the reliability is improved without the pressure in the back pressure chamber 22 rising abnormally. Furthermore, the sealing performance of the gap between the tip of the spiral wrap 12b and the end plate 11a is improved, and high efficiency can be realized.

Further, the compression chamber 10 in which the compression chamber side opening 26c of the compression chamber oil supply passage 26 of the present embodiment communicates is provided in the compression chamber 10a after the working fluid is closed as shown in FIG. 3, and the refrigerant gas is closed. It is not provided in the compression chamber 10b in a state before being inserted. That is, the compression chamber 10 communicated with the back pressure chamber 22 via the compression chamber oil supply passage 26 is the compression chamber 10a after the working fluid is closed, so that the orbiting scroll 12 can be separated from the fixed scroll 11 to This can prevent a so-called tilting phenomenon that lowers the temperature. Even if tilting occurs, it is possible to guide the pressure in the compression chamber 10 higher than the pressure before the working fluid is closed to the back pressure chamber 22. Acts to enable early return to normal operation.

According to the configuration of the present invention, since the passage area is small and does not become resistance, the pressure of the back pressure chamber does not become higher than the pressure of the compression chamber communicating with the sliding surface of the fixed scroll and the orbiting scroll. As the working fluid is not limited to the refrigerant, the scroll fluid machine such as an air scroll compressor, vacuum pump, scroll type expander and the like can be improved. It can be applied to other uses.

Claims

The motor and the compression mechanism are stored in the container,
The compression mechanism section;
An orbiting scroll formed with an upright spiral wrap on the end plate,
A fixed scroll that is combined with the orbiting scroll to form a spiral wrap upright on the end plate; and
The rotating scroll is disposed between the fixed scroll and the main bearing member that holds the seal member.
A compression chamber is formed between the orbiting scroll and the fixed scroll,
The seal member is disposed on the back of the orbiting scroll,
By the seal member, the inside of the seal member is partitioned into a high pressure region, and the outside of the seal member is divided into a back pressure chamber,
A back pressure chamber oil supply path for supplying lubricating oil from the high pressure region to the back pressure chamber;
A compression chamber oil supply path for supplying the lubricating oil from the back pressure chamber to the compression chamber;
One opening of the back pressure chamber refueling path goes back and forth through the seal member, so that the high pressure region and the back pressure chamber communicate intermittently,
The compression chamber refueling path is
A passage formed inside the orbiting scroll;
It is comprised from the recessed part formed in the said end plate of the said fixed scroll,
A scroll compressor in which the back pressure chamber and the compression chamber communicate intermittently with one opening of the passage periodically overlapping the recess according to the orbiting motion of the orbiting scroll,
The axial cross-sectional area determined by the diameter and depth of the recess is larger than the first passage area generated by the overlap of the one opening of the passage and the recess,
A scroll compressor characterized in that the axial cross-sectional area is made larger than a second passage area produced by opening the recess into the compression chamber.
2. The scroll compressor according to claim 1, wherein the first passage area is 0.9 to 1.1 times the second passage area at a position where the first passage area is maximized.
The scroll compressor according to claim 1 or 2, wherein an opening diameter of the recess is smaller than a thickness of the wrap of the orbiting scroll.
The scroll compressor according to any one of claims 1 to 3, wherein a tip seal is not provided at a tip of the wrap of the orbiting scroll.
The scroll compressor according to any one of claims 1 to 4, wherein the concave portion is provided in the compression chamber after the working fluid is closed.