WO2014103204A1

WO2014103204A1 - Scroll compressor

Info

Publication number: WO2014103204A1
Application number: PCT/JP2013/007242
Authority: WO
Inventors: 義友塚
Original assignee: ダイキン工業株式会社
Priority date: 2012-12-28
Filing date: 2013-12-10
Publication date: 2014-07-03
Also published as: KR101728261B1; RU2600206C1; CN104903583B; CN104903583A; US20150330390A1; JP5655850B2; KR20150099849A; EP2940302B1; JP2014129793A; BR112015013435A2; ES2747231T3; EP2940302A1; EP2940302A4

Abstract

A recess (78), which is formed in the bottom part (26a) of a receiving part (26) and in which oil accumulates after lubrication of a sliding part (44) of an engagement part (43), and an oil supply passage (70), which feeds the oil in the recess (78) to sliding parts (35, 45) of the compressor (20), are formed in the housing (25) of a scroll compressor.

Description

Scroll compressor

The present invention relates to a scroll type compressor, and particularly relates to a countermeasure against oil supply to a sliding portion of a compression mechanism.

Conventionally, a scroll type compressor having a fixed scroll and a movable scroll and compressing fluid between both scrolls is known and widely used in a refrigeration apparatus and the like.

Patent Document 1 discloses this type of scroll compressor. The scroll compressor has an electric motor housed in a casing and a drive shaft that is rotationally driven by the electric motor. The end of the drive shaft is engaged with the engaging portion of the end plate of the movable scroll. When the drive shaft is rotationally driven by the electric motor, the movable scroll rotates eccentrically with respect to the fixed scroll. Thereby, the compression chamber between both scrolls becomes small gradually, and fluid is compressed in this compression chamber.

Also, a housing that rotatably accommodates the drive shaft is fixed to the inner peripheral surface of the casing. An accommodation chamber is formed in the upper center portion of the housing so as to accommodate the engaging portion of the drive shaft and the movable scroll. An oil pump that sucks up oil in the oil reservoir at the bottom of the casing is provided at the lower end of the drive shaft. The oil sucked up by the oil pump along with the rotation of the drive shaft flows upward through the oil flow path in the drive shaft, to the bearing portion of the drive shaft and the sliding portion between the engagement portion of the drive shaft and the movable scroll. After that, it flows out into the storage chamber. The oil accumulated in the storage chamber sequentially flows in an oil flow path 44a extending radially outward from the storage chamber and an oil flow path 44b extending upward from the outflow side of the oil flow path 44a to slide the compression mechanism. To the part (thrust sliding surface). Thereby, in the scroll compressor of patent document 1, the thrust sliding surface of a compression mechanism is also used using the oil after utilized for lubrication of the sliding part between a drive shaft and the engaging part of a movable scroll. Lubricated.

JP 2001-214872 A

Incidentally, in the scroll compressor disclosed in Patent Document 1, in order to reliably supply the oil in the storage chamber to the sliding portion of the compression mechanism, it is necessary to always store a certain amount of oil in the storage chamber. On the other hand, when a certain amount of oil accumulates in the storage chamber in this way, the drive shaft or the engaging portion stored in the storage chamber is immersed in the oil. For this reason, in a state where the drive shaft rotates, the frictional resistance between the drive shaft or the engaging portion and the oil increases, and as a result, the agitation loss also increases and the power of the electric motor increases.

The present invention has been made in view of such a point, and an object thereof is to provide a scroll type compressor that can reduce oil agitation loss in a storage chamber.

According to a first aspect of the present invention, there is provided a casing (15), an electric motor (50) accommodated in the casing (15), a drive shaft (60) driven by the electric motor (50), and the drive shaft (60). A compression mechanism (20) having an engaging portion (43) with which an end portion is engaged, a movable scroll (40) rotating eccentrically with respect to the drive shaft (60), and a fixed scroll (30); A housing (25) having a bearing part (28) for supporting the drive shaft (60) and a housing part (26) for housing the engaging part (43), and an oil reservoir (18) of the casing (15) ) And an oil conveying mechanism (75) for conveying the oil, and the drive shaft (60) receives the oil conveyed by the oil conveying mechanism (75) on the sliding portion ( 44) Scroll-type compressors with an oil supply passage (70) to be supplied to are targeted. The scroll compressor is formed on the housing (25) at the bottom (26a) of the accommodating portion (26) and lubricates the sliding portion (44) of the engaging portion (43). A recess (78) in which the oil is stored and an oil supply passage (70) for sending the oil in the recess (78) to the sliding portions (35, 45) of the compression mechanism (20) are formed. Features.

In the first invention, the drive shaft (60) and the movable scroll (40) are connected by the end of the drive shaft (60) engaging with the engaging portion (43) of the movable scroll (40). When the electric motor (50) rotationally drives the drive shaft (60), the movable scroll (40) rotates eccentrically with respect to the fixed scroll (30). Thereby, the volume of the compression chamber between the fixed scroll (30) and the movable scroll (40) is expanded and contracted, and the fluid is compressed in the compression chamber.

The oil transfer mechanism (75) is configured to slide the oil in the oil reservoir (18) of the casing (15) through the oil supply passage (70) between the drive shaft (60) and the engaging portion (43) ( 44). Thereby, a sliding part (44) is lubricated with oil, and sliding resistance becomes small. The oil used for lubrication of the sliding part (44) of the engaging part (43) flows out into the housing part (26) that houses the engaging part (43). In the present invention, since the recess (78) is formed at the bottom of the accommodating portion (26), the oil that has flowed out flows down into the recess (78). Therefore, in the accommodating part (26), it is suppressed that oil accumulates to the circumference | surroundings of an engaging part (43). As a result, the oil stirring loss in the rotating engagement portion (43) is reduced.

The oil that has flowed down into the recess (78) is sent to the sliding portion (35, 45) of the compression mechanism (20) through the oil supply passage (90). Since the recess (78) is located at a position lower than the bottom of the storage portion (26), the oil in the storage portion (26) is sequentially supplied into the recess (78). For this reason, the oil in the recessed part (78) can be reliably supplied to the sliding parts (35, 45) of the compression mechanism (20).

The second invention is characterized in that, in the first invention, the recess (78) is constituted by an annular groove (78) surrounding the entire circumference of the bearing portion (28).

The concave portion of the second invention is constituted by an annular groove (78) surrounding the entire circumference of the bearing portion (28) of the drive shaft (60). If an annular groove is formed on the entire circumference of the bearing portion (28), the elastic coefficient of the portion of the housing (25) between the annular groove (78) and the bearing portion (28) becomes small. For this reason, even if the axis of the drive shaft (60) is inclined when the drive shaft (60) is rotated, this portion is easily deformed so as to be along the outer peripheral surface of the drive shaft (60). As a result, the outer peripheral surface of the drive shaft (60) can be prevented from coming into contact with the bearing portion (28), and the bearing load on the bearing portion (28) can be reduced.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the housing (25) is formed with an oil drainage path (80) for sending the oil in the housing part (26) to the oil reservoir (18). It is characterized by.

According to a third aspect of the present invention, after lubricating the sliding portion (44) of the engaging portion (43), a part of the oil that has flowed down into the accommodating portion (26) is passed through the oil drainage passage (80). 18) Returned to. Thereby, it is possible to avoid a shortage of oil in the oil reservoir (18). Moreover, the raise of the oil level height of a accommodating part (26) can be suppressed by returning the oil of a accommodating part (26) to an oil reservoir part (18) through an oil drainage path (80). Therefore, the engagement portion (43) can be prevented from being immersed in oil, and the oil stirring loss in the rotating engagement portion (43) is reduced.

According to a fourth invention, in the third invention, the inflow port (80a) of the oil drainage passage (80) is arranged inside the housing part (26) so as to be along the bottom part (26a) of the housing part (26). It is characterized by having an opening.

In the fourth invention, since the inlet (80a) of the oil drainage passage (80) is formed at a position along the bottom (26a) of the housing (26), the oil overflowing from the recess (78) is quickly drained. Can be led to the oil passage (80). Therefore, an increase in the oil level height of the accommodating portion (26) can be reliably suppressed.

The fifth invention is characterized in that, in the third invention, the inflow port (80a) of the oil drainage passage (80) opens into the recess (78).

In the fifth aspect of the invention, part of the oil that has flowed down from the containing portion (26) to the recess (78) is returned to the oil reservoir (18) through the oil drainage passage (80). For this reason, it can prevent that the oil of a recessed part (78) overflows to an accommodating part (26), and can suppress the raise of the oil surface height of an accommodating part (26) reliably.

In a sixth aspect based on the fifth aspect, the recess (78) has a first chamber (S1) communicating with the inlet (90a) of the oil supply passage (90) and the oil discharge passage ( A partition member (100) for partitioning the second chamber (S2) communicating with the inflow port (80a) of 80) is formed from the bottom of the recess (78) to the opening surface, and the first chamber (S1 ) Is larger than the volume of the second chamber (S2).

In the sixth invention, the interior of the recess (78) is partitioned into a first chamber (S1) and a second chamber (S2) by a partition member (100). The volume of the first chamber (S1) connected to the oil supply passage (90) is larger than the volume of the second chamber (S2) connected to the oil discharge passage (80). For this reason, the amount of oil that flows into the recess (78) after being used for lubricating the sliding portion (44) of the engaging portion (43) is also greater in the first chamber (S1) than in the second chamber (S2). Will increase. Therefore, in the present invention, sufficient oil can be secured to be supplied to the sliding portions (35, 45) of the compression mechanism (20) through the oil supply passage (90).

According to a seventh invention, in any one of the third to sixth inventions, the height of the inflow port (90a) of the oil supply passage (90) is equal to that of the inflow port (80a) of the oil discharge passage (80). It is in a position lower than the height.

In the seventh invention, the height of the inlet (90a) of the oil supply passage (90) is lower than the height of the inlet (80a) of the oil passage (80). For this reason, if the oil level is between the inlet (90a) of the oil supply passage (90) and the inlet (80a) of the oil discharge passage (80), this oil will only enter the oil supply passage (90). Sent. On the other hand, when the oil level is higher than the inlet (80a) of the oil discharge passage (80), the oil is sent to both the oil supply passage (90) and the oil discharge passage (80). That is, in the present invention, the oil that has flowed into the housing part (26) is preferentially supplied to the oil supply path (90) rather than the oil discharge path (80), so the sliding part (35 of the compression mechanism (20) , 45) can be reliably lubricated.

According to the present invention, since the concave portion (78) is formed in the bottom portion (26a) of the accommodating portion (26), the oil used for lubrication of the sliding portion (44) of the engaging portion (43) is supplied to the concave portion (78 ) Can be sent in. Thereby, in an accommodating part (26), it can suppress that an engaging part (43) is immersed in oil, and the stirring loss of the oil of the engaging part (43) in rotation can be reduced.

Further, when the oil is stirred by the engaging portion (43), there is a possibility that a compressed fluid is mixed in the oil or the oil becomes a mist. This makes it difficult for the oil to return to the oil reservoir (18) due to its own weight, resulting in a problem that the amount of oil in the oil reservoir (18) is insufficient. On the other hand, in the present invention, since the engaging portion (43) can be prevented from being immersed in oil as described above, the compressed fluid may be mixed in the oil or the oil may be in a mist shape. Can be prevented. Therefore, the oil used for lubricating the sliding portion (44) can be quickly returned to the oil reservoir (18), and so-called oil rising can be prevented.

In the second invention, it is possible to prevent the drive shaft (60) and the bearing portion (28) from coming into contact with each other by configuring the concave portion with an annular groove (78). That is, in the present invention, since the annular groove (78) serves as a recess (78) for storing oil and a so-called elastic groove, the structure of the apparatus can be simplified.

In the third aspect of the invention, since the oil that has flowed into the housing part (26) returns to the oil reservoir (18) through the oil drainage path (80), the engagement part (43) is prevented from being immersed in the oil. It is possible to suppress oil agitation by the engaging portion (43). In particular, in the fourth invention, since the height of the inflow port (80a) of the oil discharge passage (80) is located along the bottom (26a) of the storage portion (26), the oil in the storage portion (26) is discharged. It can be discharged quickly. In the fifth aspect of the invention, the inflow port (80a) of the oil discharge passage (80) opens into the recess (78), so that the oil in the recess (78) is prevented from overflowing into the storage portion (26). it can. As a result, in the fourth and fifth inventions, it is possible to effectively suppress an increase in the height of the oil level of the accommodating portion (26), and it is possible to reliably suppress oil agitation by the engaging portion (43).

In the sixth invention, the interior of the recess (78) is partitioned into a first chamber (S1) and a second chamber (S2) by a partition member (100), and the first chamber (S1) communicates with the oil supply passage (90). Since the volume of the second chamber (S2) is larger than that of the second chamber (S2), it is possible to prevent the amount of oil supplied from the oil supply passage (90) to the sliding portions (35, 45) of the compression mechanism (20) from being insufficient. Accordingly, the sliding portions (35, 45) of the compression mechanism (20) can be reliably lubricated, and as a result, the reliability of the scroll compressor can be improved.

In the seventh invention, since the inlet (90a) of the oil supply passage (90) is positioned lower than the inlet (80a) of the oil discharge passage (80), the oil supply passage (90) is connected to the compression mechanism (20). It is possible to prevent the amount of oil supplied to the sliding portions (35, 45) from being insufficient. Accordingly, the sliding portions (35, 45) of the compression mechanism (20) can be reliably lubricated, and as a result, the reliability of the scroll compressor can be improved.

Drawing 1 is a longitudinal section showing the whole scroll compressor composition concerning an embodiment. FIG. 2 is an enlarged vertical cross-sectional view of a main part of the compression mechanism and the housing according to the embodiment. FIG. 3 is a horizontal sectional view showing the internal structure of the compression mechanism. 4 is a sectional view taken along line XX of FIG. FIG. 5 is a view corresponding to FIG. 2 of the scroll compressor according to the first modification. FIG. 6 is a perspective view showing the internal structure of the central recess of the scroll compressor according to the second modification. FIG. 7 is a horizontal sectional view showing the internal structure of the central recess of the scroll compressor according to the second modification.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

An embodiment of the present invention will be described. The scroll compressor (10) of this embodiment is a hermetic compressor. The scroll compressor (10) is connected to a refrigerant circuit that performs a refrigeration cycle, and sucks and compresses refrigerant in the refrigerant circuit.

<Overall configuration of scroll compressor>
As shown in FIG. 1, in the scroll compressor (10), a compression mechanism (20), an electric motor (50), a lower bearing member (55), and a drive shaft (60) are provided in the internal space of the casing (15). ) And is housed. 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 the top to the bottom. Further, the drive shaft (60) is arranged in such a posture that its axial direction is along the height direction of the casing (15). The detailed structure of the compression mechanism (20) will be described later.

The casing (15) is provided with a suction pipe (16) and a discharge pipe (17). The suction pipe (16) and the discharge pipe (17) both penetrate the casing (15). The suction pipe (16) is connected to the compression mechanism (20). The discharge pipe (17) opens in a portion between the electric motor (50) and the compression mechanism (20) in the internal space of the casing (15).

The lower bearing member (55) includes a central cylindrical portion (56) and an arm portion (57). Although only one is shown in FIG. 1, the lower bearing member (55) is provided with three arms (57). The central cylindrical portion (56) is formed in a substantially cylindrical shape. Each arm portion (57) extends outward from the outer peripheral surface of the central cylindrical portion (56). In the lower bearing member (55), the three arm portions (57) are arranged at substantially equal angular intervals. The protruding end portion of each arm portion (57) is fixed to the casing (15). Near the upper end of the central cylindrical portion (56), a bearing metal (58) is inserted. A sub journal portion (67) of a drive shaft (60), which will be described later, is inserted through the bearing metal (58). The central cylindrical portion (56) constitutes a journal bearing that supports the sub journal portion (67).

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). A main shaft portion (61) of a drive shaft (60), which will be described later, is inserted through the rotor (52). A plurality of core cuts (51a) through which refrigerant and oil flow are formed on both ends of the stator (51) in the axial direction on the outer peripheral surface of the stator (51).

The drive shaft (60) is formed with a main shaft portion (61), a balance weight portion (62), and an eccentric portion (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). Further, in the main shaft portion (61), the portion above the balance weight portion (62) constitutes the main journal portion (64), and the sub journal portion (67) below the portion penetrating the rotor (52). ) Is formed. The main journal portion (64) is inserted through a bearing metal (28) provided in the central bulge portion (27) of the housing (25). The sub-journal part (67) is inserted through a bearing metal (58) provided in the central cylindrical part (56) of the lower bearing member (55).

The eccentric part (63) is formed at the upper end of the drive shaft (60). The eccentric part (63) is formed in a cylindrical shape having a smaller diameter than the main journal part (64), and projects from the upper end surface of the main journal part (64). The shaft center of the eccentric portion (63) is parallel to the shaft center of the main journal portion (64) (that is, the shaft center of the main shaft portion (61)) and is eccentric to the shaft center of the main journal portion (64). Yes. The eccentric part (63) is inserted into a bearing metal (44) provided in the cylindrical part (43) of the movable scroll (40). The cylindrical portion (43) of the movable scroll (40) constitutes an engaging portion with which the eccentric portion (63) is rotatably engaged.

An oil supply passage (70) is formed in the drive shaft (60). The oil supply passage (70) includes one main passage (74) and three branch passages (71 to 73). The main passage (74) extends along the axis of the drive shaft (60), and one end thereof opens to the lower end of the main shaft portion (61) and the other end opens to the upper end surface of the eccentric portion (63). ing. The first branch passage (71) is formed in the eccentric part (63). The first branch passage (71) extends from the main passage (74) to the outer side in the radial direction of the eccentric portion (63), and opens to the outer peripheral surface of the eccentric portion (63). The second branch passage (72) is formed in the main journal portion (64). The second branch passage (72) extends from the main passage (74) to the outer side in the radial direction of the main journal portion (64), and opens on the outer peripheral surface of the main journal portion (64). The third branch passage (73) is formed in the secondary journal section (67). The third branch passage (73) extends from the main passage (74) to the outer side in the radial direction of the sub journal portion (67), and is open to the outer peripheral surface of the sub journal portion (67).

An oil supply pump (75) as an oil transfer mechanism is attached to the lower end of the drive shaft (60). The oil supply pump (75) is a trochoid pump driven by the drive shaft (60). The oil supply pump (75) is disposed near the start end of the main passage (74) of the oil supply passage (70). In addition, the oil supply pump (75) has a suction port (76) that opens downward at the lower end and sucks refrigeration oil, which is lubricating oil. The oil supply pump (75) is not limited to the trochoid pump, and may be a positive displacement pump driven by the drive shaft (60). Therefore, the oil supply pump (75) may be a gear pump, for example.

Refrigerator oil, which is lubricating oil, is stored at the bottom of the casing (15). That is, the oil reservoir (18) is formed at the bottom of the casing (15). When the drive shaft (60) rotates, the oil supply pump (75) sucks and discharges refrigeration oil from the oil reservoir (18), and the refrigeration oil discharged from the oil supply pump (75) flows through the main passage (74). The refrigeration oil flowing through the main passage (74) is supplied to the lower bearing member (55), the compression mechanism (20), and the sliding portion of the drive shaft (60). Since the oil supply pump (75) is a positive displacement pump, the flow rate of the refrigeration oil in the main passage (74) is proportional to the rotational speed of the drive shaft (60).

As shown in FIG. 2, a housing (25) is provided inside the casing (15) above the electric motor (50). The housing (25) is formed in a thick disk shape, and its outer peripheral edge is fixed to the casing (15). A central concave portion (26) and an annular convex portion (29) are formed in the central portion of the housing (25). The central recess (26) is a cylindrical recess that opens on the upper surface of the housing (25). The central recess (26) constitutes a housing portion that houses the cylindrical portion (43) of the movable scroll (40) and the eccentric portion (63) of the drive shaft (60). The annular convex portion (29) is formed along the outer periphery of the central concave portion (26) and protrudes from the upper surface of the housing (25). The protruding end surface of the annular convex portion (29) is a flat surface. A ring-shaped concave groove is formed along the circumferential direction of the projecting end surface of the annular convex portion (29), and a seal member (29a) is fitted into the concave groove.

The central bulge portion (27) is formed in the housing (25). The central bulging portion (27) is located below the central concave portion (26) and bulges downward. A through-hole penetrating the central bulge portion (27) vertically is formed in the central bulge portion (27), and a bearing metal (28) is inserted into the through-hole. The main journal portion (64) of the drive shaft (60) is inserted through the bearing metal (28) of the central bulge portion (27). The central bulge portion (27) constitutes a journal bearing that supports the main journal portion (64).

<Configuration of compression mechanism>
As shown also in FIG. 2, the compression mechanism (20) includes a fixed scroll (30) and a movable scroll (40). The compression mechanism (20) is provided with an Oldham coupling (24) for restricting the rotation of the movable scroll (40).

A fixed scroll (30) and a movable scroll (40) are placed on the housing (25). The fixed scroll (30) is fixed to the housing (25) with bolts or the like. On the other hand, the movable scroll (40) is engaged with the housing (25) via the Oldham coupling (24), and is movable relative to the housing (25). The movable scroll (40) engages with the drive shaft (60) to perform eccentric rotational movement.

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 FIGS. 1 and 2) 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 FIGS. 1 and 2) of the movable side end plate portion (41).

The rear surface of the movable side end plate portion (41) of the movable scroll (40) is in sliding contact with the seal member (29a) provided on the annular convex portion (29) of the housing (25). On the other hand, the cylindrical portion (43) of the movable scroll (40) is inserted from above into the central recess (26) of the housing (25). A bearing metal (44) is inserted into the cylindrical part (43) as a sliding part with which the eccentric part (63) comes into sliding contact. An eccentric portion (63) of the drive shaft (60) described later is inserted into the bearing metal (44) of the cylindrical portion (43) from below. The cylindrical portion (43) constitutes a journal bearing that slides with the eccentric portion (63).

The fixed scroll (30) is a member in which a fixed side end plate part (31), a fixed side wrap (32), and an outer peripheral part (33) 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 FIGS. 1 and 2) of the fixed side end plate portion (31). The outer peripheral portion (33) is formed in a thick ring shape extending downward from the outer peripheral portion (33) of the fixed-side end plate portion (31) and surrounds the fixed-side wrap (32).

The discharge port (22) is formed in the fixed side end plate part (31). The discharge port (22) 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 (23) is formed in the compression mechanism (20). The start end of the discharge gas passage (23) communicates with the discharge port (22). Although not shown, the discharge gas passage (23) is formed from the fixed scroll (30) to the housing (25), and the other end opens to the lower surface of the housing (25).

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 wrap (32) and the movable wrap (42) mesh with each other to form a plurality of compression chambers (21).

In the compression mechanism (20), the movable side end plate portion (41) of the movable scroll (40) and the outer peripheral portion (33) of the fixed scroll (30) are in sliding contact with each other. Specifically, in the movable side end plate portion (41), a portion of the front surface (upper surface in FIGS. 1 and 2) on the outer peripheral side of the movable side wrap (42) is in sliding contact with the fixed scroll (30). Thrust sliding surface (45). On the other hand, the outer peripheral portion (33) of the fixed scroll (30) has its protruding end surface (the lower surface in FIGS. 1 and 2) in sliding contact with the movable thrust sliding surface (45) of the movable scroll (40). In the outer peripheral portion (33), a portion of the protruding end surface that is in sliding contact with the movable side thrust sliding surface (45) is a fixed side thrust sliding surface (35). That is, the fixed-side thrust sliding surface (35) and the movable-side thrust sliding surface (45) constitute a sliding portion of the compression mechanism (20).

2 and 4, an annular groove (78) is formed in the bottom (26a) of the central recess (26) described above. The annular groove (78) is constituted by a recess opened upward. The center of the annular groove (78) substantially coincides with the axis of the main journal portion (64) and surrounds the entire circumference of the bearing metal (28) that is the bearing portion. The annular groove (78) constitutes a so-called elastic groove. That is, in the housing (25), a cylindrical convex portion (79) protruding upward is formed between the annular groove (78) and the bearing metal (28). When the main journal portion (64) is bent radially outward during the rotation of the drive shaft (60), the cylindrical convex portion (79) is elastically deformed along the main journal portion (64). . As a result, the main journal portion (64) can be prevented from being in line contact with the bearing metal (28), so-called one-side contact, and the bearing load of the bearing metal (28) can be reduced.

¡Oil used to lubricate the bearing metal (28) of the main journal part (64) flows out into the central recess (26) of the housing (25) through the oil supply passage (70). The housing (25) has an oil drainage path (80) for sending the oil that has flowed into the central recess (26) to the oil reservoir (18), and the sliding part (fixed side) of the compression mechanism (20). An oil supply passage (90) for feeding the thrust sliding surface (35) and the movable-side thrust sliding surface (45) is formed.

The oil drainage passage (80) of the present embodiment is formed on the annular convex portion (29) of the housing (25). The oil drainage path (80) includes a horizontal hole (81) that penetrates the lower end of the annular convex part (29) in the radial direction and a vertical hole (82) that extends downward from the outflow end of the horizontal hole (81). Composed. The inflow port (80a) of the oil drainage passage (80) opens into the center recess (26). The height of the lower end of the inflow port (80a) of the oil drainage passage (80) is substantially the same as the height (26a) of the central recess (26). That is, the inflow port (80a) of the oil drainage passage (80) is disposed along the bottom (26a) of the central recess (26).

An oil catch plate (83) is provided below the vertical hole (82) of the oil drainage passage (80). The oil catching plate (83) has a diameter-expanded portion (83a) whose diameter is increased upward, and a lower nozzle portion (83b) that is extended downward from the diameter-expanded portion (83a). The outflow end (lower end) of the lower nozzle part (83b) is located inside the core cut (51a) of the stator (51).

The oil supply passage (90) is formed from the central bulging portion (27) of the housing (25) to the annular convex portion (29). The oil supply passage (90) includes a first oil supply hole (91) and a second oil supply hole (92). The first oil supply hole (91) extends obliquely upward from the annular groove (78) outward in the radial direction inside the housing (25). The inlet (91a) of the first oil supply hole (91) opens into the annular groove (78). The height of the inlet (91a) of the first oil supply hole (91) is lower than the height of the inlet (80a) of the oil discharge passage (80). The height of the inlet (91a) of the first oil supply hole (91) is higher than the bottom surface of the annular groove (78). As a result, dust collected at the bottom of the annular groove (78) can be prevented from entering the oil supply passage (90) through the inflow port (91a), and thus can be prevented from being clogged with dust in the oil supply passage (90). .

The second oil supply hole (92) is formed through the annular protrusion (29) of the housing (25) in the axial direction so as to communicate with the outflow end of the first oil supply hole (91). The screw member (93) is inserted through the second oil supply hole (92). The head (93a) of the screw member (93) closes the lower end of the second oil supply hole (92). In the second oil supply hole (92), the oil flow path is restricted by the screw member (93). That is, the screw member (93) constitutes a pressure reducing mechanism (throttle mechanism) for reducing the pressure of the oil flowing through the second oil supply hole (92).

As shown in FIGS. 2 and 3, in the outer peripheral portion (33) of the fixed scroll (30), there is an oil communication passage (94) communicating with the second oil supply hole (92), and the oil communication passage (94). A communicating oil groove (95) is formed. The inflow end of the oil communication passage (94) is connected to the second oil supply hole (92) inside the housing (25). The outflow end of the oil communication passage (94) opens toward the movable thrust sliding surface (45) of the movable scroll (40). The oil groove (95) is a concave groove formed in the fixed-side thrust sliding surface (35) of the outer peripheral portion (33), and is formed in a ring shape surrounding the periphery of the fixed-side wrap (32). The oil groove (95) communicates with the outflow end of the oil communication passage (94).

-Driving operation-
The operation of the scroll compressor (10) will be described.

<Operation to compress refrigerant>
In the scroll compressor (10), when the electric motor (50) is energized, the movable scroll (40) is driven by the drive shaft (60). The orbiting scroll (40) has its rotation motion restricted by the Oldham coupling (24), 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 (21) from near the end. When the movable scroll (40) is further moved, the compression chamber (21) is closed from the suction pipe (16), and then the compression chamber (21) is separated from the fixed wrap (32) and the movable wrap ( 42) and move toward the inner circumferential edge. In the process, the volume of the compression chamber (21) gradually decreases, and the gas refrigerant in the compression chamber (21) is compressed.

When the volume of the compression chamber (21) gradually decreases as the movable scroll (40) moves, the compression chamber (21) eventually communicates with the discharge port (22). Then, the refrigerant compressed in the compression chamber (21) (that is, high-pressure gas refrigerant) flows into the discharge gas passage (23) through the discharge port (22), and then the internal space of the casing (15). Is discharged. In the internal space of the casing (15), the high-pressure gas refrigerant discharged from the compression mechanism (20) is once guided below the stator (51) of the electric motor (50), and then the rotor (52) And flows through the gap between the stator (51) and the like, and flows out of the casing (15) through the discharge pipe (17).

The high pressure gas refrigerant discharged from the compression mechanism (20) circulates in the inner space of the casing (15) below the housing (25), and the pressure is substantially equal to the pressure of the high pressure gas refrigerant. Are equal. Therefore, the pressure of the refrigerating machine oil stored in the oil reservoir (18) in the casing (15) is also substantially equal to the pressure of the high-pressure gas refrigerant.

On the other hand, the portion of the internal space of the casing (15) above the housing (25) communicates with the suction pipe (16) (not shown), and the low pressure gas whose pressure is sucked into the compression mechanism (20) It is about the same as the pressure of the refrigerant. Therefore, in the compression mechanism (20), the pressure in the space near the outer periphery of the movable side end plate portion (41) of the movable scroll (40) is approximately the same as the pressure of the low-pressure gas refrigerant.

<Lubrication operation of sliding part>
During operation of the scroll compressor (10), the oil supply pump (75) is driven by the rotating drive shaft (60), and the refrigerating machine oil stored at the bottom of the casing (15) is the main oil supply passage (70). It is sucked up into the passage (74). A part of the refrigeration oil flowing in the main passage (74) flows into the branch passages (71 to 73), and the rest flows out from the upper end of the main passage (74). The oil (refrigerating machine oil) flowing into the third branch passage (73) is supplied to the gap between the sub journal portion (67) and the bearing metal (58), and lubrication of the sub journal portion (67) and the bearing metal (58) Used for cooling. The oil flowing into the second branch passage (72) is supplied to the gap between the main journal part (64) and the bearing metal (28), and is used for lubrication and cooling of the main journal part (64) and the bearing metal (28). The

The oil flowing into the first branch passage (71) is supplied to the gap between the eccentric portion (63) and the bearing metal (44), and is used for lubrication and cooling of the eccentric portion (63) and the bearing metal (44). The oil used for lubricating the bearing metal (44) flows out into the central recess (26).

By the way, when the oil used for lubricating the bearing metal (44) accumulates inside the central recess (26), the cylindrical portion (43) of the movable scroll (40) may be immersed in the oil. . When the cylindrical portion (43) repeats eccentric rotational motion in such a state, the oil in the central recess (26) becomes the resistance of the cylindrical portion (43), so-called stirring loss increases, and the power of the electric motor (50) is increased. Incurs an increase. Further, when the oil in the central recess (26) is stirred by the cylindrical portion (43), the high-pressure gas refrigerant in the casing (15) may be mixed into the oil, or the oil may be refined in a mist shape. There is. As a result, the oil stirred in the central recess (26) is unlikely to finally return to the oil reservoir (18) due to its own weight, and the amount of oil in the oil reservoir (18) becomes insufficient. Therefore, in this embodiment, an annular groove (78) is formed in the bottom (26a) of the central recess (26) in order to prevent oil from being stirred by the cylindrical portion (43) in the central recess (26). Yes.

Specifically, the refrigerant that has been used to lubricate the bearing metal (44) and has flowed into the central recess (26) flows down from the bottom (26a) of the central recess (26) into the annular groove (78). When the oil level in the annular groove (78) exceeds the height position of the inlet (90a) of the first oil supply hole (91), the oil in the annular groove (78) becomes the first oil supply hole (91). Flow into. This oil passes through the first oil supply hole (91) and flows upward through the second oil supply hole (92). At this time, in the second oil supply hole (92), the high pressure oil is decompressed by the screw member (93). The oil that has passed through the second oil supply hole (92) flows into the oil groove (95) via the oil communication passage (94) inside the fixed scroll (30). Thereby, in the compression mechanism (20), the sliding portion between the fixed-side thrust sliding surface (35) and the movable-side thrust sliding surface (45) is lubricated with oil.

Thus, the oil that has flowed into the central recess (26) is appropriately supplied to the sliding portion of the compression mechanism (20) through the annular groove (78) and the oil supply passage (90). As a result, the oil level height in the central recess (26) is suppressed from increasing, and the area where the cylindrical portion (43) of the movable scroll (40) is immersed in oil can be suppressed.

Also, when the oil level in the annular groove (78) rises and this oil overflows from the annular groove (78) to the central recess (26), this oil flows into the oil drainage path (80). In the oil drainage path (80), oil flows in order through the horizontal hole (81), the vertical hole (82), and the oil catching plate (83) and is guided to the core cut (51a). The oil in the core cut (51a) flows further downward along the inner peripheral surface of the casing (15) and is finally sent to the oil reservoir (18).

Thus, the oil overflowing from the annular groove (78) is returned directly to the oil reservoir (18) through the oil drainage passage (80). For this reason, it is suppressed that the oil level height in a center recessed part (26) raises, and the area where the cylindrical part (43) of a movable scroll (40) is immersed in oil can be suppressed.

-Effects of the embodiment-
According to the above embodiment, since the annular groove (78) is formed in the bottom (26a) of the central recess (26) of the housing (25), oil used for lubricating the bearing metal (44) is removed from the annular groove (78 ). Thereby, in the center recessed part (26), it can suppress that the cylindrical part (43) of a movable scroll (40) is immersed in oil, and can reduce the oil stirring loss of the rotating cylindrical part (43). As a result, the power of the electric motor (50) can be reduced and energy saving can be improved.

In addition, by suppressing the stirring of the oil by the cylindrical portion (43) in this way, it is possible to prevent the compressed fluid from being mixed into the oil or the oil from becoming a mist. Therefore, the oil used for lubricating the bearing metal (44) can be quickly returned to the oil reservoir (18), and so-called oil rising can be prevented.

In the above embodiment, an annular groove (78) is formed around the bearing metal (28) of the main journal portion (64), so that a cylindrical shape is formed between the annular groove (78) and the bearing metal (28). A convex part (79) can be formed. Thereby, even if the main journal part (64) is inclined with respect to the axial center, the cylindrical convex part (79) can be elastically deformed along the main journal part (64). Therefore, it is possible to avoid the main journal portion (64) from coming into contact with the bearing metal (28), and the bearing load on the main journal portion (64) can be reduced. Since the annular groove (78) serves as both a groove for capturing oil and guiding it to the oil supply passage (90) and a so-called elastic groove, the structure of the housing (25) can be simplified. .

In the above embodiment, a part of the oil that has flowed into the central recess (26) returns directly to the oil reservoir (18) through the oil drainage passage (80), so that the cylindrical portion (43) Can be prevented from being soaked. In particular, in this embodiment, since the inflow port (80a) of the oil drainage channel (80) is arranged along the bottom (26a) of the central recess (26), oil has overflowed from the annular groove (78). However, this oil can be promptly introduced into the oil discharge passage (80).

Moreover, in the said embodiment, the inflow port (90a) of the oil supply path (90) is opened inside the annular groove (78), and the inflow port (80a) of the oil discharge path (80) is formed inside the central recess (26). Is open. That is, the height of the inlet (90a) of the oil supply passage (90) is lower than the height of the inlet (80a) of the oil discharge passage (80). For this reason, the oil that has flowed into the central recess (26) is preferentially introduced into the oil supply passage (90) rather than the oil discharge passage (80), so the sliding portions (35, 45) oil can be supplied reliably, and the reliability of the scroll compressor (10) can be improved.

<Variation 1 of Embodiment>
The scroll compressor (10) according to the first modification shown in FIG. 5 is different from the above embodiment in the configuration of the oil discharge passage (80). The oil drainage passage (80) of Modification 1 has an inflow port (80a) that opens into the annular groove (78). Specifically, the oil drainage passage (80) extends downward from the lateral hole (81) extending radially outward from the annular groove (78) and from the radially outer end of the lateral hole (81). And a vertical hole (82). Inside the annular groove (78), the height of the inlet (90a) of the oil supply passage (90) is lower than the height of the inlet (80a) of the oil discharge passage (80).

In Modification 1, when the oil level in the annular groove (78) is between the inlet (90a) of the oil supply passage (90) and the inlet (80a) of the oil discharge passage (80), Oil is preferentially introduced into the oil supply passage (90). On the other hand, when the oil level in the annular groove (78) reaches the inlet (80a) of the oil discharge passage (80), oil is supplied to both the oil supply passage (90) and the oil discharge passage (80). Is introduced. Thus, also in the first modification, the oil that has flowed into the central recess (26) is preferentially introduced into the oil supply passage (90) rather than the oil discharge passage (80), so that the compression mechanism (20) Oil can be reliably supplied to the sliding parts (35, 45), and the reliability of the scroll compressor (10) can be improved.

Further, in Modification 1, since the oil in the annular groove (78) is sent to both the oil supply passage (90) and the oil discharge passage (80), the oil in the annular groove (78) is directed to the central recess (26). It can prevent overflowing. As a result, it is possible to more reliably prevent the cylindrical portion (43) of the movable scroll (40) from being immersed in oil.

Other operations and effects of the first modification are the same as those in the above embodiment.

<Modification 2 of Embodiment>
Modification 2 shown in FIGS. 6 and 7 has the same configuration of the housing (25) as that of Modification 1, and a partition member (100) is provided inside the annular groove (78). The partition member (100) extends in the axial direction of the annular groove (78) from the bottom part on the lower side of the annular groove (78) to the opening end on the upper side of the annular groove (78). The partition member (100) has a cross-sectional shape perpendicular to the axial direction of the annular groove (78) formed in a substantially U-shape (U-shape), and is fitted into the annular groove (78).

The partition member (100) is formed on each of the vertical wall portion (100a) curved in an arc shape along the inner peripheral surface of the annular groove (78) and both ends in the circumferential direction of the vertical wall portion (100a). And a pair of side wall portions (100b). The vertical wall (100a) is disposed at a position facing the inlet (80a) of the oil drainage passage (80). Each vertical wall portion (100a) extends in the radial direction from the inner inner peripheral surface of the annular groove (78) to the outer outer peripheral surface. By this partition member (100), the inside of the annular groove (78) is partitioned into a first chamber (S1) outside the partition member (100) and a second chamber inside the partition member (100). The inlet (90a) of the oil supply passage (90) communicates with the first chamber (S1). The second chamber (S2) communicates with the inlet (80a) of the oil discharge passage (80).

In Modification 2, the opening area at the upper end of the first chamber (S1) is larger than the opening area at the upper end of the second chamber (S2). That is, in the annular groove (78), the volume of the first chamber (S1) is larger than the volume of the second chamber (S2). For this reason, in Modification 2, much of the oil that has flowed into the central recess (26) flows down to the first chamber (S1) rather than the second chamber (S2), and is sufficient for the first chamber (S1). You can store oil. Therefore, the oil can be reliably supplied to the sliding portions (35, 45) of the compression mechanism (20) through the first chamber (S1) and the oil supply passage (90), and the reliability of the scroll compressor (10) is improved. Can be improved.

Other functions and effects of Modification 2 are the same as in the above embodiment.

<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.

In the above embodiment, the annular recess (78) is formed at the bottom (26a) of the central recess (26) so as to surround the main journal portion (64). However, the recess (78) is not necessarily annular. For example, the cross-sectional shape perpendicular to the axis may be a rectangle, a straight line, or a dot. That is, the concave portion (78) may have any shape as long as it can capture the oil that has flowed into the central concave portion (26).

As described above, the present invention relates to a scroll compressor, and is particularly useful as a countermeasure against oil supply to the sliding portion of the compression mechanism.

10 Scroll compressor 15 Casing 18 Oil reservoir 20 Compression mechanism 25 Housing 26 Central recess (housing part)
26a Bottom 28 Bearing metal (bearing part)
30 Fixed scroll 35 Fixed thrust sliding surface 40 Movable scroll 43 Cylindrical part (engagement part)
44 Bearing metal (sliding part)
45 Movable thrust sliding surface 50 Electric motor 60 Drive shaft 70 Oil supply passage 75 Oil supply pump (oil transfer mechanism)
78 Annular groove (concave)
80 Oil drain 80a Inlet (oil drain side)
90 Oil supply passage 90a Inlet (oil supply side)
100 Partition member S1 1st chamber S2 2nd chamber

Claims

The casing (15), the electric motor (50) accommodated in the casing (15), the drive shaft (60) driven by the electric motor (50), and the end of the drive shaft (60) are engaged. A compression mechanism (20) having an engaging portion (43), a movable scroll (40) rotating eccentrically with respect to the drive shaft (60), and a fixed scroll (30), and the drive shaft (60) The bearing (28) that supports the housing and the housing (25) having the accommodating portion (26) that accommodates the engaging portion (43) and the oil in the oil reservoir (18) of the casing (15) are conveyed. An oil transfer mechanism (75),
The drive shaft (60) is a scroll type in which an oil supply passage (70) for supplying the oil conveyed by the oil conveyance mechanism (75) to the sliding portion (44) of the engaging portion (43) is formed. A compressor,
The housing (25)
A recess (78) formed in the bottom portion (26a) of the housing portion (26) and in which oil after lubricating the sliding portion (44) of the engaging portion (43) is accumulated;
An oil supply path (90) for sending oil in the recess (78) to the sliding part (35, 45) of the compression mechanism (20);
A scroll type compressor characterized in that is formed.
In claim 1,
The said recessed part (78) is comprised by the cyclic | annular groove | channel (78) surrounding the perimeter of the said bearing part (28). The scroll compressor characterized by the above-mentioned.
In claim 1 or 2,
The scroll compressor characterized in that the housing (25) is formed with an oil discharge passage (80) for sending the oil in the housing part (26) to the oil reservoir (18).
In claim 3,
The inflow port (80a) of the oil drainage passage (80) is opened inside the housing part (26) along the bottom part (26a) of the housing part (26). Compressor.
In claim 3,
The scroll compressor characterized in that the inlet (80a) of the oil drainage passage (80) opens into the recess (78).
In claim 5,
Inside the recess (78) is a first chamber (S1) communicating with the inlet (90a) of the oil supply passage (90) and a first chamber (S1) communicating with the inlet (80a) of the oil drainage passage (80). A partition member (100) that partitions the two chambers (S2) is formed from the bottom of the recess (78) to the open end,
The scroll compressor characterized in that the volume of the first chamber (S1) is larger than the volume of the second chamber (S2).
In any one of Claims 3 thru | or 6,
A scroll compressor characterized in that the height of the inlet (90a) of the oil supply passage (90) is lower than the height of the inlet (80a) of the oil discharge passage (80).