CN109026706B

CN109026706B - Scroll compressor and refrigeration cycle device using same

Info

Publication number: CN109026706B
Application number: CN201810866792.9A
Authority: CN
Inventors: 近野雅嗣; 太田原优; 中村聪; 长谷川修士; 中野泰典; 坪野勇
Original assignee: Hitachi Johnson Controls Air Conditioning Inc
Current assignee: Hitachi Johnson Controls Air Conditioning Inc
Priority date: 2014-09-30
Filing date: 2015-09-29
Publication date: 2020-06-09
Anticipated expiration: 2035-09-29
Also published as: CN108980036B; CN106795881B; CN108980036A; CN109026706A; CN106795881A; WO2016052503A1; JP6302813B2; US20170306951A1; JP2016070178A

Abstract

The scroll compressor includes a fixed scroll and a orbiting scroll, and forms a suction chamber and a compression chamber by orbiting the orbiting scroll. Further, the apparatus comprises: a first space formed in the center of the back surface of the orbiting scroll and guiding the lubricating oil stored in the bottom of the hermetic container to a pressure close to the discharge pressure; a second space provided on the back surface of the orbiting scroll on the outer peripheral side of the first space, the second space having a pressure between the discharge pressure and the suction pressure; a first oil leakage path for leaking a part of the oil in the first space to the second space; an oil return passage for returning most of the oil in the first space to the bottom of the closed casing; a second oil leakage path for leaking a part of the oil in the second space to the suction chamber; and a third oil drain passage for adjusting the pressure in the second space by overflowing the oil in the second space into the compression chamber according to a difference between the pressure in the compression chamber and the pressure in the second space.

Description

Scroll compressor and refrigeration cycle device using same

The application is a divisional application; the parent application is filed under the name of 2015800527741, and the invention is named as a scroll compressor and a refrigeration cycle device using the scroll compressor.

Technical Field

The present invention relates to a scroll compressor used in a refrigeration cycle and a refrigeration cycle apparatus using the same, and more particularly to a scroll compressor including: a first space formed in a center portion of a back surface of the orbiting scroll and having a pressure close to a discharge pressure; and a second space provided on the outer peripheral side of the first space and having a pressure between the discharge pressure and the suction pressure.

Background

As a scroll compressor used in a refrigeration cycle apparatus for refrigeration, air conditioning, or the like, there is a scroll compressor described in japanese patent application laid-open publication No. 2011-58439 (patent document 1), and the like. Patent document 1 describes a scroll compressor including: a fixed scroll and a spiral scroll each having an end plate (platen, panel) and a spiral winding member standing on the end plate; a compression chamber formed by meshing the fixed scroll and the orbiting scroll with each other; a crankshaft for orbiting the orbiting scroll; a spiral bearing provided on a rear surface projection of the spiral rotating disk and supporting the spiral rotating disk so as to be movable in an axial direction with respect to an eccentric pin portion of the crankshaft and to be rotatable; a frame provided on a stationary side facing a back side of the swirling disc; a main bearing provided in the frame and rotatably supporting the crankshaft; a sealing member for sealing between the back surface side of the orbiting scroll and the frame; and an inner high-pressure hydraulic chamber and an outer back-pressure chamber partitioned by the seal member, the high-pressure hydraulic chamber being supplied with a lubricating oil at a pressure substantially equal to a discharge pressure to substantially maintain the discharge pressure, the back-pressure chamber being maintained at a pressure lower than the discharge pressure, the scroll compressor including: an oil supply unit that supplies oil in the high-pressure hydraulic chamber to the back pressure chamber side by providing a small hole in the back surface of the orbiting scroll or the frame at a portion facing the seal member, the small hole passing over the seal unit in accordance with the orbiting motion of the orbiting scroll and alternately opening to both the high-pressure hydraulic chamber side and the back pressure chamber side; and an oil supply passage provided in the swirl coil or the frame, communicating the high-pressure hydraulic chamber and the back-pressure chamber, and supplying oil in the high-pressure hydraulic chamber to the back-pressure chamber side by a pressure difference.

Further, japanese patent application laid-open No. 2005-163655 (patent document 2) describes a scroll compressor including: a non-orbiting scroll (fixed scroll) having an end plate (platen) and a spiral body (winding member) erected thereon; a orbiting scroll having an end plate (panel) and a spiral body erected thereon and engaged with the non-orbiting scroll to perform an orbiting motion, thereby forming a suction chamber or a compression chamber with the non-orbiting scroll; a back pressure chamber for applying a pressing force to the orbiting scroll to the non-orbiting scroll; a back pressure chamber fluid inflow unit for making fluid flow into the back pressure chamber in order to maintain the pressure of the back pressure chamber; and a back pressure chamber fluid outflow unit for making the fluid flowing into the back pressure chamber flow out to the suction chamber or the compression chamber.

Further, patent document 2 describes that the back pressure chamber fluid outflow means includes a back pressure control valve for controlling a pressure difference between a front side and a rear side, a throttle passage portion, and an intermittent passage portion intermittently communicating with each other by the orbiting motion of the orbiting scroll member, which are arranged in series in a back pressure chamber fluid outflow path connecting the back pressure chamber and the suction chamber or the compression chamber.

Further, the scroll compressor described in japanese patent application laid-open No. 2012-92773 (patent document 3) includes: a fixed scroll having a panel (platen) and a scroll wrap standing upright thereon; a orbiting scroll having a panel and a scroll winding member erected thereon, engaged with the fixed scroll to perform an orbiting motion, thereby forming a compression chamber with the fixed scroll; a back pressure chamber for applying a suction force to the fixed scroll to the orbiting scroll; and an oil supply path for introducing oil on a compressor discharge side into the back pressure chamber, the scroll compressor including: a compression chamber communication passage which is provided with a back pressure valve that communicates with the back pressure chamber and the compression chamber after the start of sealing and is opened and closed by a pressure difference between the front and rear sides, and controls the pressure of the back pressure chamber by allowing oil in the back pressure chamber to flow out into the compression chamber; and a suction area communication passage configured to communicate the back pressure chamber with a suction area up to the compression chamber without communicating with the compression chamber after the start of sealing, the suction area communication passage supplying oil of the back pressure chamber to the suction area.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-58439

Patent document 2: japanese patent laid-open No. 2005-163655

Patent document 3: japanese patent laid-open publication No. 2012-92773

Disclosure of Invention

Problems to be solved by the invention

In the above-described patent document 1, no consideration is given to the problem that the oil supply unit and the oil supply passage for supplying the oil of the high-pressure hydraulic chamber to the back pressure chamber side are provided, and the amount of the oil flowing from the high-pressure hydraulic chamber to the back pressure chamber can be adjusted. Therefore, when the oil supply amount required for the suction chamber and the oil supply amount required for the compression chamber are added, a large amount of high-temperature oil flows into the suction chamber, the suction gas is heated, and the heating loss (suction heating loss) increases.

Further, the above patent document 2 does not consider a problem that since the oil supplied to the bearing portion basically flows into the back pressure chamber and then all of the oil in the back pressure chamber flows into the suction chamber, a very large amount of oil necessary for the bearing flows into the suction chamber, and according to the above patent document 1, a larger amount of oil flows into the suction chamber, the suction gas is heated, the heating loss becomes larger, and a large amount of oil is also supplied to the compression chamber, so that the oil compression may occur.

In addition, in patent document 3, as in patent document 2, basically all of the oil supplied to the bearing portion flows into the back pressure chamber. Further, in patent document 3, since the compression chamber communication passage is provided in addition to the suction passage communication passage, and a part of the oil in the back pressure chamber can be directly supplied to the compression chamber without passing through the suction chamber, the supply amount from the back pressure chamber to the suction chamber can be reduced as compared with patent document 2. However, since the oil supplied to the bearing portion basically flows into the back pressure chamber, it is possible to reduce the amount of oil supplied to the suction chamber as compared with patent document 2, but it is difficult to avoid a larger amount of oil than the amount of oil supplied to the suction chamber. That is, the amount of oil supply required for the bearing portion is large, for example, about 10 times as large as the amount of oil supply required for the suction chamber and the compression chamber, but since the oil supplied to the bearing portion basically flows into the back pressure chamber, it cannot be avoided that the amount of oil supply to the suction chamber inevitably becomes large. Therefore, it is inevitable that the suction gas is heated and the heating loss becomes large. Further, since a large amount of oil is supplied from the back pressure chamber to the compression chamber and is merged with the oil from the suction chamber, the amount of oil supplied to the compression chamber increases, and there is a possibility that oil compression occurs, which is the same as the above-mentioned patent document 2, and these problems are not considered.

The purpose of the present invention is to obtain a scroll compressor capable of controlling the amount of oil supplied to a bearing portion, the amount of oil supplied to a suction chamber, and the amount of oil supplied to a compression chamber to achieve appropriate amounts, and a refrigeration cycle apparatus using the scroll compressor.

Means for solving the problems

In order to achieve the above object, the present invention provides a scroll compressor including a fixed scroll having a spiral winding member standing on a base plate and a orbiting scroll having a spiral winding member standing on a panel and engaging with the fixed scroll to perform an orbiting motion, the orbiting scroll being configured to perform an orbiting motion with respect to the fixed scroll to form a suction chamber and a compression chamber, the scroll compressor including: a first space formed in a central portion of a back surface of the swirling coil and configured to guide the lubricant oil stored in a bottom portion of the hermetic container to a pressure close to a discharge pressure; a second space provided on the back surface of the swirl coil on the outer peripheral side of the first space, the second space having a pressure between a discharge pressure and a suction pressure; a first oil leakage path through which a part of the oil in the first space leaks to the second space; an oil return passage for returning most of the oil in the first space to a bottom portion in the closed casing; a second oil leakage path for leaking a part of the oil in the second space to the suction chamber; and a third oil drain passage for adjusting the pressure in the second space by overflowing the oil in the second space into the compression chamber according to a difference between the pressure in the compression chamber and the pressure in the second space.

Another feature of the present invention resides in a refrigeration cycle apparatus used for a refrigerating and air-conditioning apparatus, the refrigeration cycle apparatus being configured using the scroll compressor configured as described above.

Effects of the invention

According to the present invention, there are provided a scroll compressor capable of controlling the amount of oil supplied to a bearing portion, the amount of oil supplied to a suction chamber, and the amount of oil supplied to a compression chamber to thereby achieve appropriate amounts, and a refrigeration cycle apparatus using the scroll compressor.

Drawings

Fig. 1 is a longitudinal sectional view showing a scroll compressor according to embodiment 1 of the present invention.

Fig. 2 is a view showing a state in which the fixed scroll and the orbiting scroll shown in fig. 1 are engaged with each other, and is viewed from a direction II-II of fig. 1.

Fig. 3 is a perspective view of the swirling coil shown in fig. 1 as viewed from above.

Fig. 4 is an enlarged sectional view of the periphery of the back pressure valve of the scroll compressor shown in fig. 1.

Fig. 5 is a view illustrating another example of the swirling coil, and is a perspective view corresponding to fig. 2.

Fig. 6 is a diagram illustrating embodiment 2 of the scroll compressor according to the present invention, and corresponds to fig. 4.

Fig. 7 is a diagram for explaining embodiment 3 of the present invention, and is a refrigeration cycle configuration diagram showing an example of a refrigeration cycle apparatus using a scroll compressor.

Detailed Description

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals denote the same or equivalent parts.

Example 1

Embodiment 1 of the scroll compressor of the present invention will be described with reference to fig. 1 to 5. Fig. 1 is a longitudinal sectional view showing an embodiment 1 of a scroll compressor according to the present invention, fig. 2 is a view showing a state in which a fixed scroll and an orbiting scroll shown in fig. 1 are engaged with each other, and is a view seen from a direction II-II of fig. 1, fig. 3 is a perspective view of the orbiting scroll shown in fig. 1, fig. 4 is an enlarged sectional view of a back pressure valve periphery of the scroll compressor shown in fig. 1, and fig. 5 is a view explaining another example of the orbiting scroll, and is a perspective view corresponding to fig. 3.

First, the overall structure of the scroll compressor of the present embodiment will be described with reference to fig. 1.

The scroll compressor 1 is configured to accommodate the compression mechanism section 2, the motor section 16, and the like in a casing (closed casing) 9.

In the compression mechanism 2, a compression chamber 13 is formed by engaging an orbiting scroll 8 with a fixed scroll 7 fixed to a frame 17, and the orbiting scroll 8 is revolved by the rotation of the motor 16 via a crankshaft (rotation shaft) 10, so that the volume of the compression chamber 13 is reduced and a compression operation is performed.

In accordance with this compression operation, the working fluid is sucked into the suction chamber 20 (see fig. 3) from the suction port 14, and the sucked working fluid is discharged into the discharge space 54 in the housing 9 from the discharge port 15 through the compression stroke of the compression chamber 13. The working fluid discharged to the discharge space 54 flows into the motor chamber 52 through a passage (not shown) formed between the outer periphery of the fixed scroll 7 and the outer periphery of the frame 17, and is then discharged from the discharge pipe 6 to the outside of the housing 9.

The fixed scroll 7 includes: a disc-shaped platen 7 a; a winding member 7b spirally and vertically provided on the base plate 7 a; a support portion 7d which is located on the outer peripheral side of the platen 7a, has a cylindrical shape, and surrounds the wound material 7b by providing an insert surface 7e having substantially the same height as the leading end surface of the wound material 7 b. The surface of the platen 7a on which the above-described winders 7b stand is referred to as a root 7c because it is between the winders 7 b.

The facing plate surface 7e is a sliding surface where the support portion 7d of the fixed scroll 7 contacts the facing plate 8a of the orbiting scroll 8. The support portion 7d is fixed to the frame 17 by bolts or the like for the fixed scroll 7, and the frame 17 integrally coupled to the fixed scroll 7 is fixed to the housing 9 by a fixing means such as welding.

The orbiting scroll 8 is disposed to face the fixed scroll 7, and the winding material 7b of the fixed scroll 7 and the winding material 8b of the orbiting scroll 8 are engaged with each other and rotatably provided in the frame 17. The orbiting scroll 8 has a spiral wrap 8b erected from a root 8c, which is a surface of a circular plate-shaped panel 8a, and a central orbiting boss (boss) 8d provided on a back surface of the panel 8 a. Further, the surface of the outer peripheral portion of the panel 8a which is in contact with the fixed scroll 7 is an insert surface 8e of the swirling scroll 8.

The tip end portion (tip of the winding material) of the winding material 8b of the orbiting scroll 8 is configured to face the tooth root 7c of the fixed scroll 7 with a slight gap. Similarly, the tip end portion (tip of the winding element) of the winding element 7b of the fixed scroll 7 is also configured to face the tooth root 8c of the orbiting scroll 8 with a slight gap.

An oil reservoir 53 for storing lubricating oil (refrigerating machine oil) is provided in the bottom of the casing 9 having a closed container structure in which the compression mechanism section 2, the motor section 16, and the like are housed. The motor 16 includes a rotor 16a and a stator 16b, and the crankshaft 10 is integrally fixed to the rotor 16 a. The crankshaft 10 is rotatably supported by the frame 17 via a main bearing 5, and is coaxial with the central axis of the fixed scroll 7.

An eccentric crank portion 10a is provided at the tip end of the crankshaft 10, a turning bearing 11 provided in a turning boss 8d of the swirling scroll 8 is inserted into the crank portion 10a, and the swirling scroll 8 is configured to be able to swirl in accordance with the rotation of the crankshaft 10.

The center axis of the orbiting scroll 8 is eccentric by a predetermined distance from the center axis of the fixed scroll 7. The winding element 8b of the orbiting scroll 8 overlaps the winding element 7b of the fixed scroll 7 with being shifted by a predetermined angle (generally 180 degrees) in the circumferential direction.

Reference numeral 12 denotes an oldham ring for relatively performing a swirling motion while constraining the swirling scroll 8 so as not to rotate with respect to the fixed scroll 7.

Fig. 2 is a view illustrating a state in which the fixed scroll 7 and the orbiting scroll 8 are engaged with each other, and is a view seen from a direction II-II in fig. 1, and therefore, the orbiting scroll 8 is shown with a cross section of the orbiting scroll wrap 8b, and a portion corresponding to the outer periphery of the panel 8a of the orbiting scroll 8 is shown by a two-dot chain line (auxiliary line).

As shown in fig. 2, a plurality of crescent-shaped compression chambers 13 (an inner swirling line side compression chamber 13a and an outer swirling line side compression chamber 13b) are formed between the fixed scroll winder 7b and the orbiting scroll winder 8b, and when the orbiting scroll 8 is revolved, the respective compression chambers 13 move in the direction of the central portion, and the volumes thereof are continuously reduced.

Reference numeral 20 denotes a suction chamber, which is a space in the middle of sucking the fluid. The phase of the swirling motion of the swirling disc 8 advances, and the suction chamber 20 becomes the compression chamber 13 after the time when the sealing of the fluid is completed.

As shown in fig. 1 and 2, the suction port 14 is provided in the fixed scroll 7. The suction port 14 is provided so as to penetrate through the outer peripheral side of the platen 7a of the fixed scroll 7 so as to communicate with the suction chamber 20.

The discharge port 15 is provided so as to penetrate through the vicinity of the spiral center of the platen 7a of the fixed scroll 7 so as to communicate with the innermost compression chamber 13.

When the crankshaft 10 is rotated by the motor unit 16 shown in fig. 1, the orbiting scroll 8 orbits around the center axis of the fixed scroll 7 at a predetermined radius of orbit. As a result, the working fluid sucked through the suction port 14, for example, a refrigerant gas (hereinafter, also simply referred to as a fluid) circulating through a refrigeration cycle is sequentially compressed in the compression chambers 13, and the compressed working fluid is discharged from the discharge port 15 to the discharge space 54 and supplied from the discharge pipe 6 to, for example, a refrigeration cycle outside the compressor as described above.

A positive displacement type or centrifugal type oil feed pump 21 is provided at the lower end of the crankshaft 10, and the oil feed pump 21 is rotated in accordance with the rotation of the crankshaft 10, so that the lubricating oil stored in the oil reservoir 53 at the bottom of the housing 9 is sucked from the lubricating oil suction port 22a of the oil feed pump housing 22 and discharged from the discharge port 21a of the oil feed pump 21. The discharged lubricating oil is delivered to the space inside the revolving boss 8d at the upper end of the crank portion 10a through hole (oil feed hole) 3 formed in the crankshaft 10 in the axial direction.

A part of the lubricating oil flowing through the through hole 3 is sent to the sub-bearing 23 through the transverse hole 24 provided in the crankshaft 10, and after lubricating the sub-bearing 23, returns to the oil reservoir 53 at the bottom of the housing 9. The other most part of the lubricating oil flowing through the through hole 3 reaches the turning boss space at the upper end of the crank portion 10a, passes through an oil groove 57 provided on the outer peripheral surface of the crank portion 10a, and then lubricates the turning bearing 11. Then, the lubricating oil lubricates the main bearing 5 provided below the orbiting bearing 11, and then returns to the oil reservoir 53 at the bottom of the housing 9 through the oil return passage 26 formed by the oil drain hole 26a and the oil drain pipe 26 b.

Here, the space in the orbiting boss formed by the oil groove 57, the orbiting bearing 11, and the like and the space for accommodating the main bearing 5 (the space formed by the frame 17, the crankshaft 10, the frame seal 56, the flange portion 34 provided in the orbiting boss 8d, and the seal member 32) are combined to form the first space 33. The first space 33 has a pressure close to the discharge pressure.

Most of the lubricating oil that has flowed into the first space 33 by lubricating the main bearing 5 and the orbiting bearing 11 passes through the oil drain hole 26a and the oil drain pipe 26b (oil return passage) and returns to the oil reservoir 53 at the bottom of the housing 9. Further, a part of the lubricating oil flows into the back pressure chamber 18 through a first oil leakage path provided between the upper end surface of the seal member 32 and the end surface of the flange portion 34 of the orbiting scroll 8d by an amount necessary for lubrication of the oldham ring 12, lubrication of the sliding portion between the fixed scroll 7 and the orbiting scroll 8, and sealing (sealing) of the tip end gap of each of the

coils

7b and 8b, and the back pressure chamber 18 is a second space provided on the outer peripheral side of the first space 33 and having a pressure between the discharge pressure and the suction pressure.

The seal member 32 is provided in an annular groove 31 provided on a surface of the frame 17 facing the flange portion 34 together with a wave spring (not shown), and partitions the first space 33 that becomes a discharge pressure and the back pressure chamber (second space) 18 that becomes a pressure between a suction pressure and a discharge pressure.

The first oil drain path is constituted by, for example, one or more slits 60 (grooves) elongated in the radial direction provided in the flange portion 34 of the swirl portion 8d and the seal member 32, and the slits 60 are arranged so as to intermittently pass over the seal member 32 by the swirling motion of the swirl coil 8, thereby intermittently communicating the first space 33 and the back pressure chamber 18.

Accordingly, the oil can flow into the back pressure chamber 18 from the first space 33 through the slit 60, which is a minute gap, by the pressure difference between the first space 33 and the back pressure chamber 18.

The arrangement of the slit 60 is not limited to the structure in which the slit intermittently passes over the seal member 32 in accordance with the swirling motion of the swirling scroll 8, and the slit may always pass over the seal member 32.

Instead of the slit 60, one or more holes (for example, circular grooves) as oil reservoirs are provided in the flange portion 34 of the swirl protrusion, and the holes perform a circular motion over the seal member 32 in accordance with the swirling motion of the swirling scroll 8. Thereby, the hole moves between the first space 33 and the back pressure chamber 18, the lubricating oil in the first space 33 is stored in the hole, the lubricating oil can be indirectly transferred and discharged to the back pressure chamber 18, and the oil in the first space 33 can be supplied to the back pressure chamber 18. The first oil drain passage may be configured in this manner.

In the present embodiment, a part of the lubricating oil flowing into the back pressure chamber 18 is configured to flow into the suction chamber 20 through a second oil leakage path described later, and is used for lubricating a winding sliding surface, a winding tip end gap, and the like, and also for sealing between compression chambers and the like.

For example, the remaining portion of the lubricating oil to the back pressure chamber 18 is configured to flow into the compression chamber 13 through a third oil leakage path described later, and is used for lubricating a winding sliding surface of the compression chamber, a winding tip clearance, and the like, and also for sealing between the compression chambers and the like.

As described above, in the present embodiment, the lubricating oil in an amount necessary for lubrication of the winding sliding surface, the winding tip clearance, and the like, sealing between compression chambers, and the like can be leaked from the first space 33 to the second space (back pressure chamber) 18 through the first oil leakage path, and the remaining lubricating oil can be returned to the oil reservoir 53 through the oil drain hole 26a and the oil drain pipe 26b after lubricating the respective bearing portions. Therefore, in the present embodiment, the oil supply amount necessary for lubrication of each bearing portion and the oil supply amount to the back pressure chamber 18 can be independently controlled. Therefore, the amount of oil supplied to the back pressure chamber 18 can be minimized.

The lubricating oil that has flowed into the back pressure chamber 18 can be supplied to the suction chamber 20 through the second oil leak passage by a required amount of supply oil, and the remaining lubricating oil can be supplied to the compression chamber 13 through the third oil leak passage. Therefore, the oil supply amount to the suction chamber 20 and the oil supply amount to the compression chamber 13 can be minimized, and therefore, the suction heating loss in the suction chamber 20 can be minimized, and the oil compression, the heating loss, and the like due to the excessive supply of the oil in the compression chamber 13 can be prevented, and thus, a highly efficient and highly reliable scroll compressor can be realized.

Next, the structure of the second oil drain path will be described with reference to fig. 2 and 3.

As shown in fig. 3, 64 is an oil hole (groove) provided in the panel surface 8e of the swirl coil 8 and serving as an oil reservoir, and as shown in fig. 2, the oil hole 64 traces a locus 65 shown in fig. 2 in accordance with the swirling motion of the swirl coil 8, thereby indirectly communicating the back pressure chamber (second space) 18 with the groove portion 66 communicating with the suction chamber 20.

In a state where the oil hole 64 communicates with the back pressure chamber 18, oil in the back pressure chamber 18 (the pressure is an intermediate pressure between the discharge pressure and the suction pressure) is stored in the oil hole 64. When the oil hole 64 communicates with the groove portion 66 (pressure is suction pressure) in accordance with the swirling motion of the swirling scroll 8, the oil in the oil hole 64 receives a pressure difference and is introduced into the suction chamber 20 through the groove portion 66.

By repeating this action, the oil in the back pressure chamber 18 is sequentially transferred to the suction chamber 20. By adjusting the volume and number of the oil holes 64, the amount of oil supplied from the back pressure chamber 18 to the suction chamber 20 can be arbitrarily adjusted.

Next, the structure of the third oil drain will be described with reference to fig. 1, 2, and 4.

First, the function of the back pressure chamber (second space) 18 will be described. In the scroll compressor 1, due to the compression action thereof, an axial force (separation force) is generated to separate the fixed scroll 7 and the orbiting scroll 8 from each other. When the axial force causes separation of the two scrolls to cause separation of the orbiting scroll 8, the sealing property of the compression chamber 13 is deteriorated, and the compression efficiency is lowered.

Here, a back pressure chamber 18 that becomes a pressure between the discharge pressure and the suction pressure is provided on the back surface side of the flat plate 8a of the orbiting scroll 8, and the orbiting scroll 8 is pressed against the fixed scroll 7 while the separation force is cancelled by the pressure (back pressure) of the back pressure chamber 18. If the pressing force at this time is too large, the sliding loss between the insert surface 8e of the orbiting scroll 8 and the insert surface 7e of the fixed scroll 7 increases, and the compressor efficiency decreases.

That is, if the optimum value of the back pressure is too small, the sealing property of the compression chamber is deteriorated, and the thermal fluid loss is increased, and if it is too large, the sliding loss is increased. Therefore, in order to improve the performance and reliability of the compressor, it is important to maintain the back pressure at an optimum value.

In order to obtain an optimum back pressure value, as shown in fig. 1, in the scroll compressor of the present embodiment, the support portion 7d of the fixed scroll 7 is provided with the third oil leakage passage (compression chamber communication passage) having a back pressure valve 61 for adjusting the back pressure of the back pressure chamber 18.

The structure of the third oil leak path will be described in detail with reference to fig. 4, which is an enlarged view showing the structure around the back pressure valve 61 in fig. 1.

The third oil drain passage (compression chamber communication passage) includes: a back pressure valve inflow passage (a space communicating with the back pressure chamber 18) 62a communicating the back pressure chamber 18 and the back pressure valve 61; a back pressure valve outlet passage (a space communicating with the compression chamber 13) 62c communicating the back pressure valve 61 and the compression chamber 13; and a space 62b in which the back pressure valve 61 is housed. The back pressure valve 61 is provided with a valve 61a so as to separate the back pressure valve inflow passage 62a and the back pressure valve outflow passage 62 c. The valve 61a is provided so as to be pressed against an opening of the back pressure valve inlet passage 62a by a spring 61b fixed to the stopper 61.

When the pressure in the back pressure valve inlet passage 62a, that is, the back pressure is higher than the total of the pressure in the space 62b introduced through the back pressure valve outlet passage 62c, that is, the pressure in the compression chamber and the pressure corresponding to the pressing force of the spring 61b, the valve 61a moves upward to communicate the back pressure valve inlet passage 62a and the back pressure valve outlet passage 62 c. That is, the back pressure valve 61 causes the fluid in the back pressure chamber 18 to overflow to the compression chamber 13 when the pressure in the back pressure chamber 18 becomes higher than a certain value, thereby adjusting the back pressure in the back pressure chamber 18 to an appropriate value.

The oil flowing into the compression chamber 13 lubricates a sliding surface of the winding material, a gap at the tip end of the winding material, and the like, and is used for sealing between the compression chambers and the like, and then discharged from the discharge port 15 to the discharge space 54. Part of the discharged oil is discharged from the discharge pipe 6 to the refrigeration cycle together with the refrigerant gas, for example, and the rest is separated from the refrigerant gas in the casing 9 and stored in the oil reservoir 53 at the bottom of the casing.

In the conventional scroll compressors described in

patent documents

2 and 3, substantially all of the lubricant oil supplied to the bearing portion, which is the first space, flows into the back pressure chamber 18, and then flows into the suction chamber 20 and the compression chamber 13. Therefore, the amount of oil supplied to the suction chamber 20 is excessive, the amount of oil supplied to the compression chamber 13 is also excessive, the refrigerant is heated and expanded by the high-temperature lubricating oil, the suction heating loss is increased, and the amount of refrigerant that can be sucked into the suction chamber 20 is also reduced, thereby reducing the volumetric efficiency. Since substantially all of the lubricating oil supplied to the bearing portion flows into compression chamber 13, an increase in heating loss and an increase in compression power due to oil compression occur.

On the other hand, in patent document 1, although the oil supply amount to the back pressure chamber 18 can be independently controlled, in order to suppress the suction heating loss in the suction chamber, if the amount of the lubricating oil flowing into the back pressure chamber 18 is suppressed, the lubricating oil cannot be sufficiently supplied to the compression chamber 13, and the sealing effect of the compression chamber 13 by the oil is reduced, so that the leakage loss is increased.

That is, at present, an appropriate amount of lubricating oil cannot be supplied to the suction chamber 20 and the compressor 13, respectively.

On the other hand, in the present embodiment, the oil supply amount to each bearing portion and the oil supply amount to the back pressure chamber can be independently controlled by the first oil leakage path, the oil supply amount from the back pressure chamber 18 to the suction chamber 20 can be independently controlled by the second oil leakage path, and the oil supply amount to each bearing portion, the suction chamber 20, and the compression chamber 13 after completion of the suction process can be appropriately adjusted by providing the third oil leakage path and supplying the oil from the back pressure chamber 18 to the compression chamber 13 through the back pressure valve 61.

In the present embodiment, the back pressure valve outlet passage 62c communicates with the compression chamber 13 after the suction process is completed and compression is started. That is, the compression chamber 13 is a compression chamber during compression after completion of the suction process, and is a compression chamber isolated from the suction chamber 20. As shown in fig. 2, the back pressure valve outlet passage 62c is located at a position where it alternately communicates with both the swirl outer line chamber 13b and the swirl inner line chamber 13a by the swirling motion of the swirl coil.

Further, reference numeral 63 shown in fig. 4 is a fixing pin for hermetically closing an end portion of a lateral hole formed for providing the back pressure valve outlet passage 62 c.

In the present embodiment, since the third oil leak path having the back pressure valve 61 is provided, the oil in the back pressure chamber 18 can be directly supplied to the compression chamber 13 through the back pressure valve 61 without passing through the suction chamber 20. The amount of oil supplied to the compression chamber 13 is the difference between the amount of oil supplied from the first space 33 to the back pressure chamber 18 through the first oil leak path and the amount of oil supplied from the back pressure chamber 18 to the suction chamber 20 through the second oil leak path. That is, although the oil is supplied from the first space 33 to the back pressure chamber 18 through the first oil leakage means, the excess oil is introduced into the compression chamber 13 by an amount determined by the second oil leakage path in the oil introduced into the suction chamber.

Therefore, by adjusting the oil supply amount to each of the first oil leak path and the second oil leak path, the oil supply amount to the suction chamber and the oil supply amount to the compression chamber can be controlled to appropriate amounts, respectively.

In general, since the oil supply amount required for sealing the compression chamber 13 is larger than the oil supply amount required for sealing the suction chamber, for example, in patent document 1, if the oil supply amount of the first oil leak path is set to the oil supply amount required for sealing the compression chamber, the oil is supplied to the suction chamber 20 too much, and the suction heating loss increases. Conversely, if the oil supply amount of the first oil leakage path is set to a small amount necessary for sealing the suction chamber 20, the oil supply in the compression chamber is insufficient, the sealing effect by the oil is reduced, and the leakage loss is increased.

In contrast, in the present embodiment, since an appropriate amount of oil can be supplied to each of the suction chamber and the compression chamber, the suction heating loss and the leakage loss can be reduced as compared with patent document 1.

Further, since the back pressure valve outlet passage 62c is formed at a position where it alternately communicates with both the swirl outer line chamber 13b and the swirl inner line chamber 13a by the swirling motion of the swirl coil, oil can be supplied to both the compression chambers, and the problem of insufficient oil supply in any of the compression chambers 13 can be avoided.

Further, by setting each oil supply amount so that the oil supply amount by the first oil leak path is larger than the oil supply amount by the second oil leak path, the difference in the oil supply amount between the first oil leak path and the second oil leak path can be supplied to the compression chamber 13, and therefore, the oil supply amount to the compression chamber 13 can be reliably secured.

Further, when this embodiment is applied to a scroll compressor using a refrigerant which is likely to become high in temperature and has a larger heat insulation index than 1.09, for example, R32 or the like as a working fluid, the suction heating loss can be further reduced, and a scroll compressor with higher efficiency can be obtained.

In the above-described embodiment, as shown in fig. 3, the example in which the second oil drain passage is configured by providing the circular oil hole (groove) 64 in the insert plate surface 8e of the orbiting scroll 8 has been described, but the present invention is not limited to this. That is, as shown in fig. 5, instead of the oil hole 64, a slit (groove) 67 having a small depth may be formed, the slit 67 may be constantly or intermittently communicated with the back pressure chamber 18 and the groove 66 communicated with the suction chamber 20, and the oil in the back pressure chamber 18 may be introduced into the suction chamber 20 by a pressure difference. In this case, the amount of oil supply can be controlled by adjusting the depth, width, length, number, or the like of the slits.

Example 2

Embodiment 2 of the scroll compressor according to the present invention will be described with reference to fig. 6. Fig. 6 is a view corresponding to fig. 4, and in fig. 6, the same reference numerals as those in fig. 1 to 5 denote the same or corresponding parts.

In example 2 as well, similarly to example 1 described above, the oil supply amount to each bearing portion and the oil supply amount to the back pressure chamber can be independently controlled by the first oil leak passage, and the oil supply amount to the suction chamber 20 from the back pressure chamber 18 can be independently controlled by the second oil leak passage. However, in embodiment 2, the third oil leak path for supplying oil from the back pressure chamber 18 to the compression chamber 13 via the back pressure valve 61, which is shown in fig. 4, is not provided. The third oil drain passage of embodiment 2 is not provided in the support portion 7d of the fixed scroll 7, but is formed by a back pressure hole 68 formed in the end plate 8a of the orbiting scroll 8 as shown in fig. 6.

The back pressure hole 68 is formed in the swirl coil panel 8a so as to communicate the back pressure chamber (second space) 18 with the compression chamber 13 after completion of the suction process and start of compression. That is, the back pressure hole 68 is provided at a position communicating only with the compression chamber 13 isolated from the suction chamber 20. The back pressure hole 68 can maintain the pressure in the back pressure chamber 18 at a value close to the average pressure in the compression chamber 13.

As described above, by providing the first oil leakage path, the second oil leakage path, and the back pressure hole 68 (third oil leakage path), the amount of oil supplied to each of the bearing portion, the suction chamber 20, and the compression chamber 13 can be appropriately adjusted, as in example 1.

According to the embodiments of the present invention described above, it is possible to control the amount of oil supplied to the bearing portion, the amount of oil supplied to the suction chamber, and the amount of oil supplied to the compression chamber, respectively, to achieve an appropriate amount of oil supply, and to achieve a high-efficiency scroll compressor with low loss. Although the oil (lubricating oil) leaked from the first to third oil leakage passages generally contains a refrigerant, the present invention will be described with a mixture containing a refrigerant in the oil as the oil.

Example 3

Embodiment 3 of the present invention will be explained with reference to fig. 7. Fig. 7 is a refrigeration cycle configuration diagram showing an example of a refrigeration cycle apparatus for a refrigeration and air-conditioning system using the scroll compressor of the present invention.

In the present embodiment, an example of a case where the present invention is applied to an air conditioner as a refrigeration cycle apparatus will be described with reference to fig. 7. In fig. 7, reference numeral 1 denotes a scroll compressor, 43 denotes a four-way valve, 40 denotes an outdoor heat exchanger (which serves as a condenser during cooling operation and serves as an evaporator during heating operation), 41 denotes an expansion valve formed of an electronic expansion valve or the like, 42 denotes an indoor heat exchanger (which serves as an evaporator during cooling operation and serves as a condenser during heating operation), and these devices are connected in order by refrigerant pipes to constitute a refrigeration cycle of the air conditioner. In the present embodiment, any of the scroll compressors described in the above embodiments is used as the scroll compressor 1.

By incorporating the scroll compressor according to any one of the embodiments of the present invention described above into the air conditioner shown in fig. 7, the operating efficiency of the air conditioner can be greatly improved, the annual energy consumption efficiency (APF) of the air conditioner can be greatly improved, and an air conditioner (refrigeration cycle device) having low annual power consumption, a wide operating range, and good usability can be obtained.

In addition, although the present embodiment 3 has been described with respect to the case of using the air conditioner in which one outdoor heat exchanger 40 and one indoor heat exchanger 42 are provided, the present invention can be similarly applied to a multi-type air conditioner or the like in which a plurality of indoor heat exchangers 42 are provided, and can also be similarly applied to a refrigeration cycle apparatus such as an air conditioner dedicated for cooling, a refrigerator, or the like.

As described above, according to the embodiments of the present invention, the oil supply amount to the bearing portion, the oil supply amount to the back pressure chamber, the oil supply amount to the suction chamber, and the oil supply amount to the compression chamber can be set to appropriate oil supply amounts of required amounts, and therefore, a scroll compressor having high efficiency and a refrigeration cycle apparatus for a refrigeration and air-conditioning using the scroll compressor can be obtained.

The present invention is not limited to the above-described embodiments, and various modifications are possible.

The above-described embodiments are examples described in detail to explain the present invention easily and understandably, and are not limited to having all the configurations described. Further, a part of the configuration of each embodiment can be added, deleted, or replaced with another configuration.

Description of the symbols

1-scroll compressor, 2-compression mechanism section, 3-through hole (oil supply hole), 5-main bearing, 6-discharge pipe, 7-fixed scroll, 7 a-platen, 7 b-winding member, 7 c-tooth root, 7 d-support section, 7 e-panel surface, 8-swirl-rotating disk, 8 a-paneling, 8 b-winding member, 8 c-tooth root, 8 d-swirl projection (projection), 8 e-panel surface, 9-housing (closed vessel), 10-crankshaft (rotating shaft), 10 a-crank section, 11-swirl bearing, 12-Oldham's ring, 13-compression chamber, 13 a-inner-swirl-side compression chamber, 13 b-outer-swirl-side compression chamber, 14-suction port, 15-discharge port, 16-motor section, 16 a-rotor, 16 b-stator, 17-frame, 18-back pressure chamber, 20-suction chamber, 21-oil supply pump, 21 a-oil supply pump, 22-an oil supply pump housing, 22 a-a lubricating oil suction port, 23-an auxiliary bearing, 24-a cross hole, 26-an oil return passage (26 a-an oil discharge hole, 26 b-an oil discharge pipe), 31-an annular groove, 32-a seal member, 33-a first space, 34-a flange portion, 40-an outdoor heat exchanger, 41-an expansion valve, 42-an indoor heat exchanger, 43-a four-way valve, 52-a motor chamber, 53-an oil reservoir, 54-an exhaust space, 56-a frame seal, 57-an oil groove, 60-a slit (groove), 61-a back pressure valve, 61a valve, 61 b-a spring, 61 c-a stopper, 62a back pressure valve inflow path, 62 b-a space, 62 c-a back pressure valve outflow path, 63-a fixed pin, 64-an oil hole (groove), 65-an oil hole trajectory, 66-a groove portion, 67-a slit (groove), and 68-a back pressure hole.

Claims

1. A scroll compressor comprises a fixed scroll having a spiral lap plate winding standing on a base plate and a orbiting scroll having a spiral lap plate winding standing on a cover plate and engaging with the fixed scroll to perform an orbiting motion, wherein a suction chamber and a compression chamber are formed by the orbiting motion of the orbiting scroll with respect to the fixed scroll,

the scroll compressor is characterized by comprising:

a first space formed in a central portion of a back surface of the swirling coil and configured to guide the lubricant oil stored in a bottom portion of the hermetic container to a pressure close to a discharge pressure;

a second space provided on the back surface of the swirl coil on the outer peripheral side of the first space, the second space having a pressure between a discharge pressure and a suction pressure;

a first oil leakage path through which a part of the oil in the first space leaks to the second space;

an oil return passage for returning most of the oil in the first space to a bottom portion in the closed casing;

a second oil leakage path for leaking a part of the oil in the second space to the suction chamber; and

a third oil leakage path for adjusting the pressure in the second space by causing the oil in the second space to overflow to the compression chamber according to the difference between the pressure in the compression chamber and the pressure in the second space,

the second oil drain passage is a groove provided on a cover surface of the swirling coil, and the second space and the suction chamber are intermittently communicated with each other by a swirling motion of the swirling coil.

2. The scroll compressor of claim 1,

the third oil leakage path is formed by a back pressure hole provided in the swirl coil and adapted to overflow the fluid in the second space to the compression chamber according to a difference between a pressure in the compression chamber and a pressure in the second space,

the pressure in the second space is adjusted by overflowing the fluid in the second space to the compression chamber.

3. The scroll compressor of claim 2,

the back pressure hole is configured to communicate the compression chamber after completion of the suction process and start of compression with the second space.

4. The scroll compressor of claim 1,

a swirl boss portion for coupling to a rotating shaft is provided on a rear surface side of the swirl disc, at least a part of the first space is formed in the swirl boss portion, and the first oil leakage path for leaking oil from the first space to the second space is formed on an end surface side of the swirl boss portion.

5. The scroll compressor of claim 4,

the second space is formed by the fixed scroll, a frame for mounting the fixed scroll, and the swirling scroll,

the first space and the second space of the turnabout boss are divided by a seal member provided on the end face side of the turnabout boss,

the first oil drain path includes: the sealing member provided on an end surface side of the turning projection; and a groove formed to intermittently supply the oil in the first space to the second space via the seal member by a swirling motion of the swirling disc.

6. The scroll compressor of claim 5,

the groove constituting the first oil drain passage is formed of a slit or one or more holes formed in an end surface of the swirling projection.

7. The scroll compressor of claim 1,

the working fluid is a refrigerant with an adiabatic index greater than 1.09.

8. A refrigeration cycle device for a refrigeration air conditioner is characterized in that,

the scroll compressor of claim 1.