JP5170197B2 - Scroll compressor - Google Patents

Scroll compressor Download PDF

Info

Publication number
JP5170197B2
JP5170197B2 JP2010220846A JP2010220846A JP5170197B2 JP 5170197 B2 JP5170197 B2 JP 5170197B2 JP 2010220846 A JP2010220846 A JP 2010220846A JP 2010220846 A JP2010220846 A JP 2010220846A JP 5170197 B2 JP5170197 B2 JP 5170197B2
Authority
JP
Japan
Prior art keywords
oil
pressure
groove
compression
space
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2010220846A
Other languages
Japanese (ja)
Other versions
JP2012077627A (en
Inventor
洋平 西出
義友 塚
Original Assignee
ダイキン工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ダイキン工業株式会社 filed Critical ダイキン工業株式会社
Priority to JP2010220846A priority Critical patent/JP5170197B2/en
Publication of JP2012077627A publication Critical patent/JP2012077627A/en
Application granted granted Critical
Publication of JP5170197B2 publication Critical patent/JP5170197B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Description

  The present invention relates to a scroll compressor, and more particularly to an oil supply structure for supplying lubricating oil to a compression mechanism.
  Conventionally, a scroll compressor has been widely used as a compressor that is connected to a refrigerant circuit that performs a refrigeration cycle and compresses the refrigerant. In this scroll compressor, a fixed scroll and a movable scroll are each provided with an end plate portion and a spiral wrap protruding from the front surface of the end plate portion. The fixed scroll and the movable scroll form a compression chamber when both laps mesh with each other.
  The scroll compressor includes, for example, a casing having a vertically long cylindrical shape whose upper and lower ends are closed, a compression mechanism having the fixed scroll and the movable scroll, and an electric motor that drives the compression mechanism. In the vertical scroll compressor as described above, the compression mechanism is generally disposed at a position above the internal space of the casing, and the electric motor is disposed at a position below the compression mechanism. The electric motor is provided with a drive shaft (crank shaft), and an eccentric part (crank pin) formed on the drive shaft is connected to the movable scroll, so that the movable scroll revolves. The drive shaft is disposed along a vertical center line of the vertically long casing.
  In the scroll compressor, during the revolution of the movable scroll, the movable scroll and the fixed scroll come into contact with each other on the outer peripheral side of the compression chamber from one end side and the other end side in the axial direction, thereby holding the compression chamber in a closed state. . That is, in the above configuration, the contact surfaces of both scrolls become thrust bearing surfaces. In other words, the laps of both scrolls mesh with each other on the inner peripheral side of the annular thrust bearing surface.
  When the orbiting scroll revolves, low-temperature and low-pressure refrigerant is sucked into the compression chamber from the outer peripheral side end of the wrap. When the movable scroll further revolves, the high-temperature and high-pressure refrigerant compressed in the compression chamber is discharged from the vicinity of the inner peripheral side end of the wrap. The refrigerant discharged from the compression mechanism is filled in the casing, and then discharged from the discharge pipe provided in the casing to the outside of the casing.
  By the way, Patent Document 1 discloses an oil supply structure for supplying oil to a compression mechanism. In the scroll compressor of Patent Document 1, an oil pump is provided at the lower end of the drive shaft so that the oil pump is immersed in an oil reservoir at the bottom of the casing. Further, in this scroll compressor, an oil supply passage extending upward from the oil supply pump is formed in the drive shaft so as to penetrate from the lower end to the upper end, and one end communicates with the oil supply passage of the drive shaft and the other end is the above-mentioned A second oil supply passage communicating with the thrust bearing surface is formed inside the end plate portion of the movable scroll. The thrust bearing surface is formed with an oil groove for expanding the high-pressure oil supplied from the oil reservoir in the circumferential direction of the thrust bearing surface.
  According to the above configuration, the lubricating oil is supplied from the oil reservoir through the oil supply passage to the oil groove on the thrust bearing surface, and further spreads from the oil groove to the entire area of the thrust bearing surface. Part of the lubricating oil that lubricated the thrust bearing surface also enters the compression chamber. The lubricating oil that has flowed into the compression chamber forms an oil film so as to block a fine clearance between the fixed scroll wrap and the movable scroll wrap. This oil film reduces the operating resistance of the movable scroll relative to the fixed scroll, and at the same time, prevents the refrigerant from leaking from the high pressure side to the low pressure side in the compression chamber.
JP-A-8-261177
  In the scroll compressor, a back pressure chamber is formed on the back side of the movable scroll (the side opposite to the thrust bearing surface in the end plate portion of the movable scroll). The back pressure chamber is partitioned into a first space on the radially inner periphery side and a second space on the radially outer periphery side. The first space is a high-pressure space, and the second space is a low-pressure space whose pressure is lower than that of the first space. An Oldham coupling is provided in the second space as a guide for the revolving operation of the movable scroll.
  In the above configuration, the first space and the oil groove are at a high pressure, and the pressure in the second space is lower than that in the first space. Therefore, the pressure in the second space is lower than that in the oil groove. . Therefore, the high-pressure lubricating oil supplied to the oil groove may leak to the second space formed on the outer peripheral side of the oil groove due to a pressure difference. If a large amount of oil leaks into the second space, the lubricating oil is agitated when the movable scroll or Oldham coupling operates, and the lubricating oil becomes a resistance, preventing the smooth movement of the compression mechanism. End up.
  The present invention was devised in view of such problems, and its purpose is to provide a large amount of oil from the oil groove on the thrust bearing surface to the low pressure side space (second space on the outer peripheral side) of the back pressure chamber. It is to prevent leakage and to prevent the compression mechanism from operating smoothly due to oil agitation loss.
  The first invention includes a compression mechanism (20), a drive mechanism (50) that drives the compression mechanism (20), and a casing (15) that houses the compression mechanism (20) and the drive mechanism (50). An oil sump (67) in which lubricating oil is accumulated is formed in the casing (15), and the compression mechanism (20) includes a fixed scroll (30) and a movable scroll (40). 30) and the movable scroll (40) are respectively formed of an annular thrust bearing surface (29a, 29b) and a thrust bearing surface (29a, 29b) that slide on a plane perpendicular to the axial direction of the drive mechanism (50). A spiral wrap (32, 42) meshing with each other on the inner peripheral side, and a back pressure chamber (74) on the back side of the movable scroll (40) with the first inner space (74a) and the outer peripheral side The second space (74b) is divided into a second space (74b) and the second space (74b) is maintained at a lower pressure than the first space (74a). Formed on the outer peripheral side of the wrap (32, 42) on at least one of the material (73) and the thrust bearing surface (29a, 29b) and supplied with lubricating oil having a pressure higher than the pressure in the second space (74b) It is assumed that the scroll compressor has an oil groove (70).
The scroll compressor has a pressure lower than that of the oil groove (70) on the outer peripheral side of the oil groove (70) on one or both of the thrust bearing surfaces (29a, 29b) , and the second space ( An oil recovery groove (75) having the same pressure as or lower than that of 74b) is formed.
  In the first aspect of the invention, when the compression mechanism (20) is operated, high-pressure lubricating oil is supplied from the oil sump (67) of the casing (15) to the oil groove (70) of the thrust bearing surface (29a, 29b). The The high-pressure lubricating oil supplied to the oil groove (70) exudes from the oil groove (70) and spreads over the entire thrust bearing surface (29a, 29b). The lubricating oil that has spread on the thrust bearing surfaces (29a, 29b) flows into the compression chamber (25) when moving toward the inner circumferential direction of the oil groove (70). The lubricating oil flowing into the compression chamber (25) adheres to the surfaces of the fixed scroll (30) and the movable scroll (40) to form an oil film, and performs a lubricating action and a sealing action. On the other hand, the lubricating oil spreading from the oil groove (70) to the thrust bearing surfaces (29a, 29b) flows into the oil recovery groove (75) when moving toward the outer periphery of the oil groove (70). Accordingly, it is possible to prevent the lubricating oil from flowing into the second space (74b) of the back pressure chamber (74).
  In a second aspect based on the first aspect, the oil recovery groove (75) is formed by meshing the wrap (32) of the fixed scroll (30) and the wrap (42) of the movable scroll (40). It is characterized by being connected to a fluid suction portion (25a) into the compression chamber (25). The fluid suction portion (25a) includes a suction hole of the compression mechanism (20), a portion connected to the compression chamber (25) immediately after the start of suction, and the like.
  In the second aspect of the invention, since the suction pressure of the compression chamber (25) acts on the oil recovery groove (75), the lubricating oil flowing into the oil recovery groove (75) from the oil groove (70) 75) and the compression chamber (25) is sucked into the compression chamber (25).
  According to a third aspect, in the first or second aspect, the thrust bearing surface (29a, 29b) is such that the oil recovery groove (75) surrounds the entire oil groove (70) from the radially outer side. It is characterized by comprising a groove extending in the circumferential direction.
  In the third aspect of the invention, the lubricating oil is trapped in the oil recovery groove (75) in the entire periphery of the oil groove (70).
  According to a fourth invention, in the first or second invention, the oil groove (70) includes a high-pressure portion (70a) in the vicinity of the inflow port of the lubricating oil to the oil groove (70) and the inflow port. A low pressure portion (70b) that is lower in pressure than the high pressure portion (70a) at a distant portion, and the oil recovery groove (75) at least places the high pressure portion (70a) of the oil groove (70) from the outer peripheral side. It is characterized by a groove extending in the circumferential direction of the thrust bearing surface (29a, 29b) so as to surround it.
  In the fourth aspect of the invention, the lubricating oil is captured by the oil recovery groove (75) around the high pressure portion (70a) of the oil groove (70).
  According to a fifth invention, in any one of the first to fourth inventions, the oil recovery groove (75) is formed in a thrust bearing surface (29a) on the fixed scroll (30) side. It is said.
  The oil recovery groove (75) may be formed on the thrust bearing surface (29b) on the movable scroll (30) side, but the position of the oil recovery groove (75) changes with the operation of the movable scroll (40). Therefore, it is necessary to form the thrust bearing surfaces (29a, 29b) in a wide area where the oil recovery groove (75) is always closed even during the operation of the movable scroll (40). On the other hand, in the fifth invention, the oil recovery groove (75) is formed in the thrust bearing surface (29a) on the fixed scroll (30) side, so that the fixed scroll (30) and the movable scroll (40) The area of the thrust bearing surface (29a, 29b) that always slides can be reduced.
  According to the above configuration, when the high-pressure lubricating oil that has flowed into the oil groove (70) from the oil reservoir (67) oozes out from the oil groove (70) to the thrust bearing surfaces (29a, 29b) and moves toward the outer circumferential direction. First, it is trapped in the oil recovery groove (75). Here, the second space (74b) of the back pressure chamber (74) has a lower pressure than the first space (74a), and the pressure is lower than that of the oil groove (70). Therefore, if the oil recovery groove (75) is not provided, a large amount of lubricating oil in the oil groove (70) tends to flow into the second space (74b) of the back pressure chamber (74). If a large amount of lubricating oil flows into the second space (74b), the lubricating oil resists the operation of the movable scroll (40) and the Oldham coupling (22) provided in the second space (74b). And stirring loss occurs.
  On the other hand, according to the present invention, since the oil recovery groove (75) having a low pressure is provided on the outer peripheral side of the oil groove (70), the oil groove (70) is provided on the thrust bearing surfaces (29a, 29b). The lubricating oil that oozes out and spreads to the outer peripheral side is captured in the oil recovery groove (75) before flowing out into the second space (74b). Therefore, it is possible to prevent the lubricating oil from flowing into the second space (74b) of the back pressure chamber (74) more than necessary. As a result, the lubricating oil does not become a resistance to the operation of the movable scroll (40) and Oldham coupling (22), so that the agitation loss becomes smaller than before, the compression mechanism (20) moves smoothly, and efficient operation is achieved. It becomes possible.
  Further, in the conventional structure, when the second space (74b) of the back pressure chamber (74) is set to an intermediate pressure, if the operating condition changes and the high pressure decreases, the oil supply differential pressure (the difference between the high pressure and the intermediate pressure) ) Becomes smaller, the amount of oil supplied to the thrust bearing surfaces (29a, 29b) is insufficient, and the reliability of the thrust bearing surfaces (29a, 29b) may be reduced or the compression performance may be reduced due to insufficient lubricating oil There is. On the other hand, in the present invention, even when the differential pressure oil supply is adopted in the intermediate pressure structure, the oil recovery groove (75) having a lower pressure is provided around the oil groove (70) having a high pressure. By providing this, the oil supply differential pressure can be reliably ensured, so that it is possible to prevent a decrease in the reliability of the thrust bearing surfaces (29a, 29b) and a decrease in the compression performance due to an oil shortage.
  According to the second aspect of the invention, the lubricating oil flowing into the oil recovery groove (75) from the oil groove (70) is transferred from the connecting portion between the oil recovery groove (75) and the compression chamber (25) to the compression chamber (25). Since it is sucked in, it can prevent more reliably that lubricating oil flows into the 2nd space (74b) of a back pressure chamber (74). Therefore, it becomes easy to make stirring loss small, and operation | movement of a compression mechanism (20) can be made smoother.
  According to the third aspect of the invention, since the lubricating oil is captured by the oil recovery groove (75) in the entire periphery of the oil groove (70), the second space of the back pressure chamber (74) from the oil groove (70). Lubricating oil hardly flows out to (74a), and the stirring loss can be reliably reduced.
  According to the fourth aspect of the invention, the lubricating oil is trapped in the oil recovery groove (75) around the high pressure portion (70a) of the oil groove (70), while the oil recovery is recovered around the low pressure portion (70b). Although the groove (75) is not formed, since the pressure of the lubricating oil in the low pressure part (70b) is reduced, the lubricating oil flows from the low pressure part (70b) to the second space (74b) of the back pressure chamber (74). It does not flow in large quantities. Therefore, the stirring loss can be reduced as compared with the conventional case. The separation force due to the pressure of the lubricating oil increases around the high-pressure part (70a). However, installing a low-pressure oil recovery groove (75) in the surrounding area suppresses excessive separation force and the behavior of the movable scroll. Is stabilized. Further, since the oil recovery groove (75) may be short, the oil recovery groove (75) can be easily formed on the thrust bearing surfaces (29a, 29b). Since the oil recovery groove (75) has a lower pressure than the oil groove (70), the oil recovery groove (75) has a lower pressure even at the low pressure part (70b) of the oil groove (70). Become.
  According to the fifth aspect, since the oil recovery groove (75) is formed in the thrust bearing surface (29a) on the fixed scroll (30) side, the oil recovery groove (75) is on the movable scroll (40) side. Compared to the case where it is formed on the thrust bearing surface (29b), the area of the thrust bearing surface (29a, 29b) on which the fixed scroll (30) and the movable scroll (40) always slide can be reduced, so that the compression mechanism (20) can be miniaturized.
It is a longitudinal section showing the whole scroll compressor structure of an embodiment. It is a longitudinal cross-sectional enlarged view which shows the compression mechanism of the scroll compressor of embodiment. It is a bottom view of the fixed scroll of an embodiment. It is a bottom view of the fixed scroll which concerns on the modification of embodiment.
  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
<Overall configuration of scroll compressor>
The overall configuration of the scroll compressor (10) will be described with reference to FIG.
  As shown in FIG. 1, the scroll compressor (10) of this embodiment is a hermetic compressor. The scroll compressor (10) is connected to a refrigerant circuit (not shown) that performs a refrigeration cycle, and sucks and compresses refrigerant in the refrigerant circuit.
  The scroll compressor (10) has a casing (15). In the internal space of the casing (15), there are a compression mechanism (20) for compressing the refrigerant gas, an electric motor (drive mechanism) (50) for driving the compression mechanism (20), and a drive connected to the electric motor (50). The shaft (60) and the lower bearing member (55) that supports the drive shaft (60) are accommodated. The casing (15) is a sealed container formed in a vertically long cylindrical shape. In the internal space of the casing (15), a compression mechanism (20), an electric motor (50), and a lower bearing member (55) are arranged in order from top to bottom. The drive shaft (60) is arranged such that its axial direction is along the height direction of the casing (15).
  A suction pipe (16) and a discharge pipe (18) are attached to the casing (15). The suction pipe (16) and the discharge pipe (18) both penetrate the casing (15). The suction pipe (16) is connected to the compression mechanism (20). The discharge pipe (18) opens at a portion between the electric motor (50) and the compression mechanism (20) in the internal space of the casing (15). The internal space of the casing (15) is partitioned into a space above and a space below by the compression mechanism (20). The space below the compression mechanism (20) is a space that becomes a high pressure.
  The lower bearing member (55) is fixed to the casing (15). The lower bearing member (55) rotatably supports the lower end portion of the drive shaft (60). On the other hand, the electric motor (50) includes a stator (51) and a rotor (52). The stator (51) is fixed to the casing (15). The rotor (52) is arranged coaxially with the stator (51). The drive shaft (60) is inserted through the rotor (52).
  The drive shaft (crank shaft) (60) is formed with a main shaft portion (61), a balance weight portion (62), and an eccentric portion (crank pin) (63). The balance weight part (62) is disposed in the middle of the main shaft part (61) in the axial direction. The main shaft portion (61) has a lower portion than the balance weight portion (62) passing through the rotor (52) of the electric motor (50), and a lower end portion thereof is supported by the lower bearing member (55). In addition, the main shaft portion (61) is rotatably supported at an upper portion of the balance weight portion (62) by an upper bearing (23) included in a housing (21) of the compression mechanism (20) described later. The eccentric part (63) protrudes from the upper end surface of the main shaft part (61). The eccentric part (63) has an axis that is eccentric with respect to the axis of the main shaft part (61), and is engaged with a movable scroll (40) of a compression mechanism (20) described later.
  A main oil supply passage (65) is formed in the drive shaft (60). One end of the main oil supply passage (65) opens at the lower end of the drive shaft (60), and the other end opens at the upper end of the drive shaft (60). An oil supply pump (66) that supplies oil to the main oil supply passage (65) is provided at the lower end of the drive shaft (60). When the drive shaft (60) rotates, the refrigerating machine oil (lubricating oil) collected in the oil sump (67) formed at the bottom of the internal space of the casing (15) (the space where high pressure is applied) is supplied to the oil supply pump (66). Is sucked up into the main oil supply passageway (65).
  A branch passage (not shown) extending in the radial direction of the drive shaft (60) is formed in the main oil supply passage (65). A part of the refrigerating machine oil flowing through the main oil supply passage (65) flows into the branch passage and is supplied to sliding portions such as the lower bearing member (55) and the upper bearing (23) of the housing (21).
<Compression mechanism>
The configuration of the compression mechanism (20) will be described with reference to FIGS.
  As shown in FIGS. 1 and 2, the compression mechanism (20) includes a housing (21), a fixed scroll (30), and a movable scroll (40). The compression mechanism (20) is provided with an Oldham coupling (22) for restricting the rotation of the movable scroll (40).
  The housing (21) is formed in the shape of a thick disk, and its central portion bulges downward in FIG. 1 to constitute the upper bearing (23). The housing (21) is fixed to the casing (15) with its outer peripheral surface in contact with the inner peripheral surface of the casing (15). The housing (21) is configured such that the main shaft portion (61) of the drive shaft (60) passes through the center portion thereof. The upper bearing (23) of the housing (21) holds a journal bearing that rotatably supports a portion of the main shaft portion (61) of the drive shaft (60) above the balance weight portion (62). Yes.
  A fixed scroll (30) and a movable scroll (40) are placed on the housing (21). The fixed scroll (30) is fixed to the housing (21) with bolts or the like. On the other hand, the movable scroll (40) is not fixed to the housing (21), and engages with the drive shaft (60) to make a revolving motion.
  The movable scroll (40) is a member in which a movable side end plate portion (41), a movable side wrap (42), and a cylindrical portion (43) are integrally formed. The movable side end plate portion (41) is formed in a disc shape. The movable side wrap (42) is formed in a spiral wall shape, and protrudes from the front surface (upper surface in FIG. 1) of the movable side end plate portion (41). The cylindrical portion (43) is formed in a cylindrical shape and protrudes from the back surface (the lower surface in the figure) of the movable side end plate portion (41). An eccentric part (63) of the drive shaft (60) is inserted into the cylindrical part (43).
  The fixed scroll (30) is a member in which the fixed side end plate portion (31) and the fixed side wrap (32) are integrally formed. The fixed side end plate portion (31) is formed in a disc shape. The fixed side wrap (32) is formed in a spiral wall shape, and protrudes from the front surface (the lower surface in FIG. 1) of the fixed side end plate portion (31). The fixed side end plate portion (31) includes an outer peripheral wall portion (33) surrounding the fixed side wrap (32). The inner peripheral side surface of the outer peripheral wall portion (33) is in sliding contact with the movable side wrap (42) together with the fixed side wrap (32) to form a compression chamber (25).
  Note that the compression mechanism (20) of the scroll compressor has an asymmetric spiral structure in which the number and length of spirals of the fixed side wrap (32) are different from the number and length of spirals of the movable side wrap (42). It is configured.
  A discharge port (26) is formed in the fixed side end plate portion (31). The discharge port (26) is a through hole formed in the vicinity of the center of the fixed-side end plate portion (31), and passes through the fixed-side end plate portion (31) in the thickness direction. A suction pipe (16) is inserted in the vicinity of the outer periphery of the fixed-side end plate part (31).
  A discharge gas passage (28) is formed in the compression mechanism (20). The discharge gas passage (28) is a passage formed from the fixed scroll (30) to the housing (21). One end of the discharge gas passage (28) communicates with the discharge port (26), and the other end opens on the lower surface of the housing (21).
  In the compression mechanism (20), the fixed scroll (30) and the movable scroll (40) have the front surface of the fixed side end plate portion (31) and the front surface of the movable side end plate portion (41) facing each other, and the fixed side wrap (32) The movable wraps (42) are arranged so as to mesh with each other. In the compression mechanism (20), the fixed side wrap (32) of the fixed scroll (30) and the movable side wrap (42) of the movable scroll (40) are engaged with each other, so that a plurality of compression chambers (25) are formed. It is formed.
  As described above, the compression mechanism (20) is a compression chamber formed by engaging the scrolls (30, 40) with the fixed scroll (30) and the movable scroll (40) each having a spiral wrap. (25) Further, the compression mechanism (20) is formed in both scrolls (30, 40) so as to slide in contact with the axial direction from one end side and the other end side outside in the radial direction of the compression chamber (25). Thrust bearing surfaces (29a, 29b) are provided. The thrust bearing surface (29a, 29b) is a surface formed at a portion where the surface on the fixed scroll (30) side and the surface on the movable scroll (40) side always contact during the revolution of the movable scroll (40).
  In other words, the fixed scroll (30) and the movable scroll (40) each have an annular thrust bearing surface (29a, 29b) that slides on a plane perpendicular to the axial direction of the drive mechanism (50), and a thrust. There are provided spiral wraps (32, 42) meshing with each other on the inner peripheral side of the bearing surfaces (29a, 29b).
<Lubrication structure of compression mechanism>
As shown in FIG. 3, the compression mechanism (20) has an oil groove (70) formed in the thrust bearing surface (29a, 29b) so as to be positioned around the compression chamber (25). . The oil groove (70) is formed in the thrust bearing surface (29a) on the fixed scroll (30) side. As shown in FIG. 3 which is a bottom view of the fixed scroll (30), the oil groove (70) is not an annular groove continuous in the circumferential direction, but a part in the circumferential direction (right side portion in FIG. 3) is interrupted. C-shaped groove.
  Refrigerating machine oil supplied from the oil reservoir (67) to the space between the back surface of the movable side end plate (41) and the upper end surface of the drive shaft (60) is supplied to the movable end plate (41) from the thrust bearing. In order to introduce into the oil groove (70) of the surface (29a), a branch oil supply passage (71) is formed as an oil supply passage on the compression mechanism (20) side. In the branch oil supply passage (71), the radially inner end (71a) opens toward the upper end surface of the drive shaft (60) on the back side of the movable end plate (41), and the radially outer end ( 71b) opens toward the thrust bearing surface (29a) on the front side of the movable side end plate portion (41). Also, the thrust groove surface (29a) on the fixed scroll (30) side has the oil groove (70) on the radially outer end (71b) of the branch oil supply passage (71) during the revolution of the movable scroll (40). An inflow recess (inlet) (72) is formed so as to always communicate with the opening.
  A seal ring (seal member) (73) is disposed on the back side of the movable scroll (40). The seal ring (73) is held at a position near the inner periphery of the upper surface of the housing (21) and is in pressure contact with the back surface of the movable side end plate portion (41). The seal ring (73) includes a back pressure chamber (74) formed on the back surface side of the movable scroll (40), a first space (74a) on the inner peripheral side where the refrigerating machine oil is introduced and becomes a high pressure, The first space (74a) is partitioned into a second space (74b) on the outer peripheral side that has a lower pressure than the first space (74a). The second space (74b) may be connected to the suction side of the compression mechanism (20) so as to be at a low pressure, or a back pressure adjustment mechanism is provided, and the compression chamber (25) is in the intermediate pressure position. The refrigerant gas may be introduced to achieve an intermediate pressure.
  On the thrust bearing surface (29a, 29b), an oil recovery groove (75) having a pressure lower than that of the oil groove (70) is formed on the radially outer peripheral side of the oil groove (70). The oil recovery groove (75) is a passage formed in the thrust bearing surface (29a) on the fixed scroll (30) side, and is compressed so as to surround the entire oil groove (70) from the radially outer peripheral side. It is constituted by a groove extending in the circumferential direction of the chamber (25). One end of the oil recovery groove (75) is connected to the refrigerant suction portion (25a) into the compression chamber (25), and the other end extends in the circumferential direction of the compression chamber (25). Further, the other end side of the oil recovery groove (75) terminates in the vicinity of the fluid suction portion (25a) into the compression chamber (25).
  In FIG. 3, a circle indicated by a broken line outside the oil recovery groove (75) indicates that the outer peripheral surface of the movable scroll (40) is closest to the center of the compression chamber (25) during the turning of the movable scroll (40). It is an envelope (C) made by connecting dots. The thrust bearing surfaces (29a, 29b) are the surfaces where the fixed scroll (30) and the movable scroll (40) are always in contact with the inner peripheral side of the envelope (C). The groove (75) is formed inside the envelope.
  In the above configuration, the oil groove (70) and the oil recovery groove (75) are not arranged concentrically because the outer circumference of the compression chamber (25) is circular while the envelope (C) is circular. In order to cope with the uneven arrangement space (placement of the oil groove (70) and oil recovery groove (75)) due to non-circularity, the refrigeration oil in the oil groove (70) flows from the inflow recess (72). The pressure decreases as the downstream side becomes farther away, making it difficult for the thrust bearing surfaces (29a, 29b) to bleed, whereas the oil groove (70) is moved closer to the compression chamber (25) toward the downstream side, and the thrust bearing surface (29a 29b) to facilitate the introduction of refrigerating machine oil into the compression chamber (25).
-Driving action-
Next, the operation of the scroll compressor (10) will be described.
  In the scroll compressor (10), when the electric motor (50) is energized, the drive shaft (60) rotates. Then, the movable scroll (40) is driven as the eccentric part (63) turns on the circular orbit having the radius of the eccentricity. The orbiting scroll (40) has its rotation motion restricted by the Oldham coupling (22), and does not rotate but only revolves.
  When the orbiting scroll (40) revolves, the low-pressure gas refrigerant that has flowed into the compression mechanism (20) through the suction pipe (16) becomes the outer peripheral side of the fixed side wrap (32) and the movable side wrap (42). It is sucked into the compression chamber (25) from the vicinity of the end (suction part (25a)). When the movable scroll (40) further revolves, the compression chamber (25) is closed from the suction pipe (16), and then the compression chamber (25) is separated from the fixed side wrap (32) and the movable side wrap ( 42) and move toward the inner circumferential edge. In the process, the volume of the compression chamber (25) gradually decreases, and the gas refrigerant in the compression chamber (25) is compressed.
  When the compression chamber (25) moves toward the inner peripheral side end of the fixed side wrap (32) and the movable side wrap (42) while gradually reducing the volume as the movable scroll (40) moves, Eventually, the compression chamber (25) communicates with the discharge port (26). At this time, the refrigerant (that is, high-pressure gas refrigerant) compressed in the compression chamber (25) flows into the discharge gas passage (28) through the discharge port (26), and then the inside of the casing (15). It is discharged to a portion between the compression mechanism (20) and the electric motor (50) in the space. The high-pressure gas refrigerant discharged into the internal space of the casing (15) cools the electric motor (50) and applies high-pressure pressure to the refrigerating machine oil in the oil reservoir (67) that collects at the bottom of the casing (15). It flows out of the casing (15) through the discharge pipe (18).
  During the operation of the scroll compressor (10), the drive shaft (60) rotates, and the refrigeration oil stored in the oil sump (67) at the bottom of the casing (15) is driven by the oil supply pump (66) to the drive shaft (60 ) Is sucked into the main oil supply passage (65). The refrigerating machine oil flowing through the main oil supply passage (65) is supplied to the sliding portions of the lower bearing member (55) and the upper bearing (23) and the sliding portion of the compression mechanism (20).
  Oil supply to the compression mechanism (20) is performed as follows.
  First, a part of the refrigerating machine oil flowing out from the upper end of the drive shaft (60) is supplied to the sliding portion between the eccentric portion (63) and the cylindrical portion (43) of the movable scroll (40). The high-pressure pressure of the refrigerating machine oil acts on the entire first space (74a) on the inner peripheral side of the seal ring (73), so that it is partitioned inside the seal ring (73) in the back pressure chamber (74). The first space (74a) is a high-pressure space.
  On the other hand, the remaining refrigerating machine oil flowing out from the upper end of the drive shaft flows into the oil groove (70) of the thrust bearing surface (29a, 29b) through the branch oil supply passage (71). The high-pressure refrigeration oil that has flowed into the oil groove (70) exudes from the oil groove (70) to the thrust bearing surfaces (29a, 29b) and spreads over the entire thrust bearing surfaces (29a, 29b). In the thrust bearing surface (29a, 29b), the inner peripheral side of the oil groove (70) is open to the compression chamber (25), so that the oil groove (70) moves to the inner peripheral side of the thrust bearing surface (29a, 29b). The expanding refrigeration oil flows into the compression chamber (25). The refrigerating machine oil flowing into the compression chamber (25) adheres to the surfaces of the fixed wrap (32) and the movable wrap (42) to form an oil film, and is formed between both wraps (32, 42). Since the minute gap is filled, the refrigerant is prevented from leaking from the high pressure side to the low pressure side of the compression chamber (25). Excess refrigeration oil in the compression chamber (25) is discharged together with the refrigerant from the compression mechanism (20).
  Of the back pressure chamber (74), the second space (74b) defined outside the seal ring (73) is a space having a lower pressure than the first space (74a). Therefore, the pressure in the second space (74b) is lower than that in the oil groove (70). Therefore, if the oil recovery groove (75) is not provided, the refrigerating machine oil in the oil groove (70) is in the back pressure chamber (74). ) To flow into the second space (74b). If a large amount of refrigerating machine oil flows into the second space (74b), the refrigerating machine oil becomes a resistance to the operation of the movable scroll (40) and the Oldham coupling (22), resulting in a stirring loss.
  On the other hand, in this embodiment, since the low pressure oil recovery groove (75) is provided on the outer peripheral side of the oil groove (70), the oil groove (70) oozes out to the thrust bearing surfaces (29a, 29b). The refrigerating machine oil spreading to the outer peripheral side is captured in the oil recovery groove (75) before flowing out into the second space (74b). Therefore, refrigeration oil does not flow into the second space (74b) of the back pressure chamber (74) more than necessary. The refrigerating machine oil captured by the oil recovery groove (75) is introduced into the compression chamber (25) from the refrigerant suction portion (25a) into the compression chamber (25). Part of this refrigeration oil becomes an oil film and contributes to the sealing of the compression chamber (25), and the surplus is discharged from the compression mechanism (20) together with the refrigerant.
  The refrigerating machine oil contained in the refrigerant discharged from the compression mechanism (20) is in the form of fine oil droplets, and when it passes through the discharge port (26) and is discharged into the internal space of the casing (15), part of it It flows out of the casing (15) through the discharge pipe (18). The remaining refrigeration oil is separated from the refrigerant in the internal space of the casing (15) and returns to the oil sump (67). The refrigerating machine oil that has flowed out of the casing (15) together with the high-pressure gas refrigerant is separated from the gas refrigerant in an oil separator (not shown), and then merged with the low-pressure refrigerant and sent back to the compression mechanism (20).
-Effect of the embodiment-
When the high-pressure refrigeration oil that has flowed into the oil groove (70) from the oil sump (67) oozes out from the oil groove (70) to the thrust bearing surface (29a, 29b) and travels toward the outer circumferential direction, first the oil recovery groove Captured at (75). Here, since the second space (74b) of the back pressure chamber (74) has a lower pressure than the first space (74a), the second space (74b) is more than the oil groove (70). Pressure is lowered. Therefore, if the oil recovery groove (75) is not provided, a large amount of refrigeration oil in the oil groove (70) tends to flow out into the second space (74b) of the back pressure chamber (74). If a large amount of refrigerating machine oil flows into the second space (74b), the refrigerating machine oil becomes a resistance to the operation of the movable scroll (40) and the Oldham coupling (22), resulting in a stirring loss.
  In contrast, according to the present embodiment, since the low-pressure oil recovery groove (75) is provided on the outer peripheral side of the oil groove (70), the oil groove (70) extends to the thrust bearing surfaces (29a, 29b). The refrigerating machine oil that exudes and spreads to the outer peripheral side is captured in the oil recovery groove (75) before flowing out to the second space (74b). Therefore, refrigeration oil does not flow more than necessary into the second space (74b) of the back pressure chamber (74). Therefore, since refrigeration oil does not become a resistance to the operation of the movable scroll (40) and Oldham coupling (22), the agitation loss is smaller than before, and the compression mechanism (20) moves smoothly and enables efficient operation. become.
  Further, according to the present embodiment, the refrigeration oil that has flowed into the oil recovery groove (75) from the oil groove (70) enters the compression chamber (25) from the connection portion between the oil recovery groove (75) and the compression chamber (25). Since it is sucked in, it can prevent more reliably that refrigeration oil flows into the 2nd space (74b) of a back pressure chamber (74). Therefore, the smooth operation of the compression mechanism (20) can be further ensured.
  Furthermore, according to this embodiment, since the refrigeration oil is trapped in the oil recovery groove (75) in the entire periphery of the oil groove (70), the second space of the back pressure chamber (74) from the oil groove (70). Refrigerating machine oil hardly flows out to (74a), and the stirring loss can be reliably reduced.
  On the other hand, the oil recovery groove (75) may be formed on the thrust bearing surface (29b) on the movable scroll (30) side, but in this case, the position of the oil recovery groove (75) is changed with the operation of the movable scroll (40). The thrust bearing surfaces (29a, 29b) need to be formed in a wide area where the oil recovery groove (75) is always closed even during the operation of the movable scroll (40). On the other hand, according to the present embodiment, the oil recovery groove (75) is formed in the thrust bearing surface (29a) on the fixed scroll (30) side, so the fixed scroll (30) and the movable scroll (40) However, the area of the thrust bearing surface (29a, 29b) that always slides can be reduced, and the compression mechanism can be downsized.
-Modification of the embodiment-
In the above embodiment, the oil groove (70) and the oil recovery groove (75) may be configured as shown in FIG.
  In FIG. 4, the inflow recess (inlet) (72) is disposed at one end of the C-shaped oil groove (70). Although not shown, the radially outer end of the branch oil supply passage (71) is formed at a position corresponding to the inflow recess (72), and the branch oil supply passage ( 71) and the oil groove (70) are always in communication.
  The oil collecting groove (75) includes the oil groove (70) in the vicinity of the inflow port of the lubricating oil to the oil groove (70) and the high pressure portion at a portion away from the inflow port. The compression chamber (25) so as to surround at least the high-pressure part (70a) of the oil groove (70) from the radially outer side when considered to include a low-pressure part (70b) lower in pressure than (70a) It is comprised by the groove | channel extended in the circumferential direction. That is, as the oil groove (70) is closer to the inflow recess (72), the inner pressure is higher and the oil is more likely to leak. An oil recovery groove (75) surrounds at least the portion where oil is liable to leak from the outer periphery in the radial direction. Since the oil recovery groove (75) has a lower pressure than the oil groove (70), the oil recovery groove (75) has a lower pressure even at the low pressure part (70b) of the oil groove (70). Become.
  In this modification, the lubricating oil is trapped in the oil recovery groove (75) around the high pressure portion (70a) of the oil groove (70), while the oil recovery groove (75) is surrounded around the low pressure portion (70b). ) Is not formed, but since the pressure of the lubricating oil in the low pressure part (70b) is reduced, it does not flow into the second space (74b) of the back pressure chamber (74) in a large amount. Therefore, the stirring loss can be reduced as compared with the conventional scroll compressor.
<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.
  In the above embodiment, the example in which the present invention is applied to the scroll compression mechanism (20) having the asymmetric spiral structure has been described. However, in the compression mechanism (20) having the symmetrical spiral structure, an oil groove ( 70) and an oil recovery groove (75) may be formed.
  Further, the oil groove (70) and the oil recovery groove (75) may be formed on the movable scroll (40) side, and the shape of the oil groove (70) is also the same as that of the movable scroll (40) when formed on the fixed scroll (30). Also in the case of forming, it is not limited to the C shape as in the above embodiment, but may be an annular shape.
  Furthermore, the oil recovery groove (75) may be connected to the compression chamber (25) at the same pressure as the second space (74b) of the back pressure chamber (74) or at a pressure lower than that. It is preferable to connect at the position immediately after the hole or the start of inhalation. Further, the second space (74b) of the back pressure chamber (74) may be an intermediate pressure space, and in this case, the position where the oil recovery groove (75) is connected to the compression chamber (25) is compressed. What is necessary is just a position when the pressure of a chamber (25) becomes lower than 2nd space (74b). When the second space (74b) is set to an intermediate pressure, the refrigerating machine oil accumulated in the second space (74b) can also be recovered by the oil recovery groove (75), thereby further reducing the operating resistance of the compression mechanism (20). Driving efficiency.
  Further, in the conventional structure, when the second space (74b) of the back pressure chamber (74) is set to an intermediate pressure, if the operating condition changes and the high pressure decreases, the oil supply differential pressure (the difference between the high pressure and the intermediate pressure) ) Becomes smaller and the amount of oil supplied to the thrust bearing surfaces (29a, 29b) becomes insufficient, and there is a risk that the reliability of the thrust bearing may be reduced or the compression performance may be reduced due to insufficient oil. Even when differential pressure oil supply is adopted in the pressure structure, the oil supply differential pressure can be surely provided by providing the oil recovery groove (75) having a lower pressure around the oil groove (70) having a high pressure. Therefore, it is possible to prevent a decrease in the reliability of the thrust bearing and a decrease in the compression performance due to the shortage of oil.
  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.
  As described above, the present invention is useful for an oil supply structure for supplying lubricating oil to a compression mechanism of a scroll compressor.
10 Scroll compressor
15 casing
20 Compression mechanism
25 Compression chamber
25a Inhalation part
29 Thrust bearing surface
30 Fixed scroll
40 movable scroll
50 Drive mechanism
67 Oil sump
70 Oil groove
70a High pressure section
70b Low pressure section
71 Oil supply passage
73 Seal member
74 Back pressure chamber
74a 1st space
74b 2nd space)
75 Oil recovery groove

Claims (5)

  1. A compression mechanism (20); a drive mechanism (50) that drives the compression mechanism (20); and a casing (15) that houses the compression mechanism (20) and the drive mechanism (50). 15) An oil sump (67) is formed in the lubricating oil.
    The compression mechanism (20) has a fixed scroll (30) and a movable scroll (40),
    The fixed scroll (30) and the movable scroll (40) respectively include an annular thrust bearing surface (29a, 29b) that slides on a plane orthogonal to the axial direction of the drive mechanism (50), and a thrust bearing surface (29a, 29b) having spiral wraps (32, 42) meshing with each other on the inner peripheral side,
    The back pressure chamber (74) on the back side of the movable scroll (40) is divided into a first space (74a) on the inner peripheral side and a second space (74b) on the outer peripheral side, and is more than the first space (74a). The seal member (73) that holds the two spaces (74b) at a low pressure, and is formed on the outer peripheral side of the wrap in at least one of the thrust bearing surfaces (29a, 29b), and is higher than the pressure in the second space (74b). A scroll compressor having an oil groove (70) to which high-pressure lubricating oil is supplied,
    One or both of the thrust bearing surfaces (29a, 29b) has a pressure lower than that of the oil groove (70) on the outer peripheral side of the oil groove (70 ), and the same pressure as the second space (74b) or A scroll compressor characterized in that an oil recovery groove (75) having a lower pressure is formed.
  2. In claim 1,
    The oil recovery groove (75) is a portion for sucking fluid into the compression chamber (25) formed by meshing the wrap (32) of the fixed scroll (30) and the wrap (42) of the movable scroll (40) ( A scroll compressor characterized in that it is connected to 25a).
  3. In claim 1 or 2,
    The oil recovery groove (75) is constituted by a groove extending in the circumferential direction of the thrust bearing surface (29a, 29b) so as to surround the entire oil groove (70) from the radially outer side. Scroll compressor.
  4. In claim 1 or 2,
    The oil groove (70) has a lower pressure than the high pressure portion (70a) at a portion away from the high pressure portion (70a) near the inlet of the lubricating oil to the oil groove (70) and the inlet. Including a low pressure part (70b),
    The oil recovery groove (75) is constituted by a groove extending in the circumferential direction of the thrust bearing surface (29a, 29b) so as to surround at least the high pressure portion (70a) of the oil groove (70) from the outer peripheral side. Scroll compressor characterized by.
  5. In any one of Claims 1-4,
    The scroll compressor characterized in that the oil recovery groove (75) is formed in a thrust bearing surface (29a) on the fixed scroll (30) side.
JP2010220846A 2010-09-30 2010-09-30 Scroll compressor Active JP5170197B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2010220846A JP5170197B2 (en) 2010-09-30 2010-09-30 Scroll compressor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2010220846A JP5170197B2 (en) 2010-09-30 2010-09-30 Scroll compressor

Publications (2)

Publication Number Publication Date
JP2012077627A JP2012077627A (en) 2012-04-19
JP5170197B2 true JP5170197B2 (en) 2013-03-27

Family

ID=46238178

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2010220846A Active JP5170197B2 (en) 2010-09-30 2010-09-30 Scroll compressor

Country Status (1)

Country Link
JP (1) JP5170197B2 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5516651B2 (en) 2012-06-14 2014-06-11 ダイキン工業株式会社 Scroll compressor
JP5459376B1 (en) * 2012-09-28 2014-04-02 ダイキン工業株式会社 Scroll compressor
JP5459377B1 (en) * 2012-09-28 2014-04-02 ダイキン工業株式会社 Scroll compressor
JP6503901B2 (en) * 2015-06-02 2019-04-24 ダイキン工業株式会社 Scroll compressor

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003328963A (en) * 2002-05-16 2003-11-19 Daikin Ind Ltd Scroll compressor
JP2010065635A (en) * 2008-09-12 2010-03-25 Hitachi Appliances Inc Scroll compressor

Also Published As

Publication number Publication date
JP2012077627A (en) 2012-04-19

Similar Documents

Publication Publication Date Title
EP2574791B1 (en) Scroll compressor
US7322809B2 (en) Rotary compressor with sealing portions and oil-supply groove
US9903370B2 (en) Scroll compressor with reduced upsetting moment
KR101529415B1 (en) Scroll-type compressor
US9617996B2 (en) Compressor
JP5655850B2 (en) Scroll compressor
KR20120109088A (en) Scroll compressor
US9316225B2 (en) Scroll compressor with thrust sliding surface oiling groove
JP5170197B2 (en) Scroll compressor
JP2010101188A (en) Scroll compressor
JP5691352B2 (en) Scroll compressor
JP5880513B2 (en) Compressor
JP2017025789A (en) Rotary compressor
JP2013137002A (en) Scroll compressor
JP5209279B2 (en) Scroll compressor
JP2014125908A (en) Scroll compressor
JP2012057595A (en) Compressor and refrigeration apparatus
WO2019240134A1 (en) Scroll compressor
JP6608101B1 (en) Scroll compressor
JP2013036459A (en) Compressor
KR20210010808A (en) Scroll compressor
JP4802855B2 (en) Scroll compressor
JP2013087678A (en) Scroll compressor
JP2016176458A (en) Compressor
JP2012097576A (en) Rotary compressor

Legal Events

Date Code Title Description
RD02 Notification of acceptance of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7422

Effective date: 20120625

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20120927

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20121002

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20121030

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20121204

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20121217

R151 Written notification of patent or utility model registration

Ref document number: 5170197

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R151

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20160111

Year of fee payment: 3