Scroll compressor and refrigeration device

Abstract

To suppress rupture of an oil film between a movable scroll and a floating member.SOLUTION: A scroll compressor (10) comprises a compression mechanism (30) having a fixed scroll (31) and a movable scroll (35), a drive shaft (40), and a floating member (50). The movable scroll includes a scroll-side contact surface (39) that comes into contact with the floating member, and a boss portion (38) that is provided on the inner peripheral side (Ri) of the scroll-side contact surface and is connected to an eccentric shaft portion (42) of the drive shaft. The floating member includes a floating-side contact surface (54) that comes into contact with the movable scroll, and a recess (53) that is provided on the inner peripheral side of the floating-side contact surface and forms a crank chamber (55) that receives the boss portion. An outer space (A) is formed on the outer peripheral side (Ro) of the floating-side contact surface. The floating member is provided with a communication passage (59) that provides communication between the crank chamber and the outer space.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a scroll compressor and a refrigeration device. [Background technology]

[0002] The scroll compressor described in Patent Document 1 includes a compression mechanism having a fixed scroll and a movable scroll, a drive shaft, and a floating member. A high pressure or an intermediate pressure is supplied to the back side of the floating member, which pushes the floating member up. The floating member presses the movable scroll against the fixed scroll. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-193576 A Summary of the Invention [Problem to be solved by the invention]

[0004] The floating member functions as a thrust bearing that supports the movable scroll. The floating member tilts in response to the overturning of the movable scroll. The floating member can favorably support the movable scroll while being in contact with the movable scroll with almost no gap.

[0005] The drive shaft has a main shaft portion and an eccentric shaft portion eccentric with respect to the main shaft portion. The boss portion of the movable scroll is connected to the eccentric shaft portion of the drive shaft. The floating member has a crank chamber formed by a recess. The boss portion of the movable scroll is housed in the crank chamber of the floating member. Lubricating oil is supplied from the crank chamber to the sliding portion between the movable scroll and the floating member to form an oil film.

[0006] Since the working fluid is present in the crank chamber, a portion of the working fluid may be mixed with the lubricating oil supplied from the crank chamber to the sliding portion between the movable scroll and the floating member.

[0007] If the working fluid is mixed into the lubricating oil, the oil film is likely to break at the sliding portion between the movable scroll and the floating member, which can cause poor lubrication or seizure at the sliding portion between the movable scroll and the floating member.

[0008] An object of the present disclosure is to suppress oil film rupture between a movable scroll and a floating member in a scroll compressor. [Means for solving the problem]

[0009] A first aspect of the present disclosure is directed to a scroll compressor (10). The scroll compressor (10) includes a compression mechanism (30) having a fixed scroll (31) and a movable scroll (35), a drive shaft (40) having a main shaft portion (41) and an eccentric shaft portion (42) eccentric with respect to the main shaft portion (41), and a floating member (50) that presses the movable scroll (35) against the fixed scroll (31). The movable scroll (35) has a scroll-side contact surface (39) that contacts the floating member (50), and a scroll-side contact surface (39) that is provided on the inner peripheral side (Ri) of the scroll-side contact surface (39) and extends toward the floating member (50). and a boss portion (38) connected to the eccentric shaft portion (42), the floating member (50) includes a floating side contact surface (54) that contacts the movable scroll (35), and a recess (53) that is provided on the inner peripheral side (Ri) of the floating side contact surface (54) and forms a crank chamber (55) that accommodates the boss portion (38), an outer space (A) is formed on the outer peripheral side (Ro) of the floating side contact surface (54), and the floating member (50) is provided with a communicating passage (59) that communicates between the crank chamber (55) and the outer space (A).

[0010] In the scroll compressor (10) according to the first aspect, the working fluid present in the crank chamber (55) flows through the communication passage (59) into the outer space (A). The working fluid is less likely to mix with the oil supplied from the crank chamber (55) to the sliding portion between the scroll-side contact surface (39) and the floating-side contact surface (54). Breaking of the oil film in the sliding portion between the scroll-side contact surface (39) and the floating-side contact surface (54) can be suppressed.

[0011] A second aspect of the present disclosure is directed to the scroll compressor (10) according to the first aspect. In the scroll compressor (10), the communication passage (59) is formed of a groove portion (59a) provided in the floating-side contact surface (54).

[0012] In the scroll compressor (10) according to the second aspect, the communication passage (59) can be easily formed by providing the groove (59a) in the floating-side contact surface (54).

[0013] A third aspect of the present disclosure is directed to the scroll compressor (10) according to the first aspect. In this scroll compressor (10), the floating member (50) is provided with a partition wall (58) that separates the crank chamber (55) from the outer space (A), and the communication passage (59) is defined by a through hole (59b) formed in the partition wall (58).

[0014] In the scroll compressor (10) according to the third aspect, the communication passage (59) can be easily formed by forming the through hole (59b) in the partition wall (58) separating the crank chamber (55) from the outer space (A).

[0015] A fourth aspect of the present disclosure is directed to the scroll compressor (10) according to any one of the first to third aspects. In this scroll compressor (10), the communication passage (59) is arranged on the opposite side in the radial direction (R) of the drive shaft (40) to the suction port (34a) of the compression mechanism (30), with the drive shaft (40) therebetween.

[0016] According to the scroll compressor (10) of the fourth aspect, the communication passage (59) can be located away from the suction port (34a). Mixing of oil into the working fluid sucked into the compression mechanism (30) through the suction port (34a) can be suppressed.

[0017] A fifth aspect of the present disclosure is directed to the scroll compressor (10) according to any one of the first to fourth aspects. The scroll compressor (10) includes a casing (20) that houses the compression mechanism (30), the drive shaft (40), and the floating member (50), the drive shaft (40) extends in a vertical direction (Z), a lower bottom portion (20a) of the casing (20) is provided with an oil reservoir (24) that retains oil (L), the drive shaft (40) is provided with an oil passage (43) that extends through an interior (40a) of the drive shaft (40) in the vertical direction (Z), and the oil passage (43) connects the crank chamber (55) and the oil reservoir (24).

[0018] According to the scroll compressor (10) of the fifth aspect, oil (L) can be introduced from the oil reservoir (24) in the lower bottom portion (20a) of the casing (20) to the crank chamber (55) via the oil passage (43) of the drive shaft (40).

[0019] A sixth aspect of the present disclosure is directed to a refrigeration system (1). The refrigeration system (1) includes the scroll compressor (10) according to any one of the first to fifth aspects. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 shows a refrigeration device (1) according to a first embodiment. [Diagram 2] FIG. 2 shows a front cross-sectional view of the scroll compressor (10) according to the first embodiment. [Diagram 3] FIG. 3 is a front cross-sectional view showing the periphery of the crank chamber (55) and the outer space (A) in the first embodiment. [Figure 4]FIG. 4 shows a plan view of the floating-side contact surface (54) of the floating member (50) according to the first embodiment. [Diagram 5] FIG. 5 shows the cross-sectional shape of a groove (59a) serving as the communication passage (59) according to the first embodiment. [Figure 6] FIG. 6 is a front cross-sectional view showing the periphery of the crank chamber (55) and the outer space (A) in the second embodiment. [Figure 7] FIG. 7 shows the cross-sectional shape of a through hole (59b) serving as a communication passage (59) according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below, and various modifications are possible within the scope of the technical idea of ​​the present disclosure. Since each drawing is intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary for ease of understanding.

[0022] First Embodiment (Refrigeration equipment) A scroll compressor (10) according to a first embodiment will be described. The scroll compressor (10) is applied to a refrigeration system (1). FIG. 1 shows the refrigeration system (1). The refrigeration system (1) includes a refrigerant circuit (1a) in which a refrigerant circulates as a working fluid. The refrigerant circuit (1a) of the refrigeration system (1) includes a scroll compressor (10), a condenser (heat radiator) (2), a pressure reduction mechanism (expansion mechanism) (3), and an evaporator (4). The pressure reduction mechanism (3) is, for example, an expansion valve or a capillary tube. The refrigerant circuit (1a) performs a vapor compression refrigeration cycle. The refrigeration system (1) is applied to, for example, an air conditioner or a chiller.

[0023] (Compressor) 2 is a front cross-sectional view of the scroll compressor 10. The scroll compressor 10 includes a casing 20, a compression mechanism 30, a drive shaft 40, a floating member 50, a frame 60, a motor 70 serving as an electric motor, a lower bearing member 80, and an oil pump 90.

[0024] Hereinafter, the direction in which the axis of the drive shaft (40) extends is referred to as the axial direction and is indicated by (Z). The axial direction of the drive shaft (40) extends in the vertical direction. The vertical direction is also indicated by (Z), just like the axial direction. The upper side in the axial direction (vertical direction) is indicated by (Za). The lower side in the axial direction (vertical direction) is indicated by (Zb).

[0025] The direction perpendicular to the axis of the drive shaft (40) is the radial direction and is indicated by (R). The side farther from the axis of the drive shaft (40) in the radial direction is the outer circumferential side and is indicated by (Ro). The side closer to the axis of the drive shaft (40) in the radial direction is the inner circumferential side and is indicated by (Ri). The direction of rotation of the drive shaft (40) is the circumferential direction and is indicated by (T).

[0026] The scroll compressor (10) is disposed vertically. A compression mechanism (30), a floating member (50), a frame (60), a motor (70), a lower bearing member (80), and an oil pump (90) are housed in the casing (20) in this order from top to bottom. The drive shaft (40) extends axially (vertically) within the casing (20).

[0027] (Casing) The casing (20) houses the compression mechanism (30), the drive shaft (40), the floating member (50), the frame (60), the motor (70), the lower bearing member (80), and the oil pump (90).

[0028] The casing (20) is a cylindrical sealed container that extends vertically in the axial direction (vertical direction). A partition member (21) is provided in an upper portion of the interior of the casing (20). The partition member (21) extends in the radial and circumferential directions. The partition member (21) divides the internal space of the casing (20) in the axial direction (vertical direction). A low-pressure space (Sa) is defined below the partition member (21). A high-pressure space (Sb) is defined above the partition member (21).

[0029] A suction pipe (22) is connected to the casing (20). A discharge pipe (23) is connected to the casing (20). The suction pipe (22) passes through an outer peripheral wall of the casing (20). The suction pipe (22) communicates with the low pressure space (Sa). The discharge pipe (23) passes through an upper wall of the casing (20). The discharge pipe (23) communicates with the high pressure space (Sb).

[0030] An oil reservoir (24) is provided in the lower bottom (20a) of the casing (20). The oil reservoir (24) stores lubricating oil (L). The lubricating oil (L) lubricates each sliding part of the scroll compressor (10).

[0031] (Compression mechanism) The compression mechanism (30) is provided in the casing (20). The compression mechanism (30) compresses a working fluid (e.g., a refrigerant). The working fluid is a gas. The compression mechanism (30) has a fixed scroll (31) and a movable scroll (35). The movable scroll (35) is meshed with the fixed scroll (31).

[0032] The fixed scroll (31) includes a fixed end plate portion (32), a fixed side wrap (33), and an outer circumferential wall portion (34). The fixed side end plate portion (32) is disk-shaped. The fixed side wrap (33) is a spiral wall that describes an involute curve and protrudes downward from the lower surface of the fixed side end plate portion (32). The outer circumferential wall portion (34) is formed so as to surround the fixed side wrap (33) from the outer circumferential side and protrudes downward from the lower surface of the fixed side end plate portion (32). The tip surface (lower end surface) of the outer circumferential wall portion (34) and the tip surface (lower end surface) of the fixed side wrap (33) are substantially flush with each other.

[0033] The movable scroll (35) is also called an orbiting scroll. The movable scroll (35) is disposed below the fixed scroll (31). The movable scroll (35) includes a movable end plate portion (36), a movable wrap (37), a boss portion (38), and a scroll contact surface (39). The movable end plate portion (36) is disk-shaped. The movable wrap (37) is in the form of a spiral wall that describes an involute curve, and protrudes upward from the upper surface of the movable end plate portion (36).

[0034] The boss portion (38) is provided at the center of the lower surface (rear surface) of the movable end plate portion (36). The scroll side contact surface (39) is provided on the lower surface (rear surface) of the movable end plate portion (36) radially outer than the boss portion (38). In other words, the boss portion (38) is provided on the lower surface (rear surface) of the movable end plate portion (36) radially inner than the scroll side contact surface (39).

[0035] The boss portion (38) is cylindrical. The boss portion (38) extends downward from the center of the lower surface (back surface) of the movable-side end plate portion (36) toward the floating member (50). A bearing (38a) is fitted into the inner periphery of the boss portion (38). The boss portion (38) is connected to an eccentric shaft portion (42) of the drive shaft (40) (to be described later). The scroll-side contact surface (39) is ring-shaped surrounding the boss portion (38) when viewed in the axial direction. The scroll-side contact surface (39) comes into contact with a floating-side contact surface (54) of the floating member (50) (to be described later).

[0036] In the compression mechanism (30), a movable wrap (37) of the movable scroll (35) is meshed with a fixed wrap (33) of the fixed scroll (31). A compression chamber (C) is formed in a region surrounded by the fixed end plate portion (32) and the fixed wrap (33) of the fixed scroll (31) and the movable end plate portion (36) and the movable wrap (37) of the movable scroll (35). In the compression chamber (C), a working fluid is compressed.

[0037] An intake port (34a) is provided at an upper end of a partial circumferential region of the outer circumferential wall portion (34) of the fixed scroll (31). The intake port (34a) extends in the radial direction. The intake port (34a) is also called an intake port. The intake port (34a) communicates with the compression chamber (C) of the compression mechanism (30). The intake port (34a) communicates with the low-pressure space (Sa).

[0038] A discharge port (32a) penetrates the center of the fixed end plate portion (32) of the fixed scroll (31) in the axial direction. The discharge port (32a) is also called a discharge port. The discharge port (32a) communicates with the compression chamber (C) of the compression mechanism (30). The discharge port (32a) communicates with the high-pressure space (Sb).

[0039] The low-pressure working fluid flows through the suction pipe (22) into the low-pressure space (Sa) in the casing (20), and then flows through the suction port (34a) into the compression chamber (C) of the compression mechanism (30). The working fluid is compressed in the compression chamber (C) of the compression mechanism (30) to a high pressure. The high-pressure working fluid flows through the discharge port (32a) into the high-pressure space (Sb), and then is discharged through the discharge pipe (23) to the outside of the casing (20) (for example, to the condenser (2) of the refrigerant circuit (1a)).

[0040] (Drive shaft) The drive shaft (40) extends in the axial direction (vertical direction) within the casing (20). The drive shaft (40) has a main shaft portion (41) and an eccentric shaft portion (42). The eccentric shaft portion (42) is provided at an axial upper end of the main shaft portion (41). The outer diameter of the eccentric shaft portion (42) is smaller than the outer diameter of the main shaft portion (41). The axis (42a) of the eccentric shaft portion (42) is eccentric with respect to the axis (41a) of the main shaft portion (41) by an eccentric distance (r).

[0041] The eccentric shaft portion (42) of the drive shaft (40) is inserted into the boss portion (38) of the movable scroll (35) from below in the axial direction. The eccentric shaft portion (42) of the drive shaft (40) is connected to the boss portion (38) of the movable scroll (35). The eccentric shaft portion (42) of the drive shaft (40) is rotatably (slidably) supported by the boss portion (38) of the movable scroll (35) via a bearing (38a). The movable scroll (35) is concentric with the eccentric shaft portion (42) of the drive shaft (40).

[0042] The drive shaft (40) is provided with an oil passage (43). The oil passage (43) extends axially (vertically) through the interior (40a) of the drive shaft (40). The oil passage (43) serves to supply lubricating oil (L) to each sliding part of the scroll compressor (10).

[0043] (Floating components) The floating member (50) is also called a float housing. The floating member (50) has a cylindrical shape extending in the axial direction (vertical direction). The floating member (50) is provided below the movable scroll (35) and above the frame (60) in the casing (20).

[0044] The floating member (50) is supported to be freely swingable relative to the casing (20). The floating member (50) is not directly fixed to the casing (20). The floating member (50) supports the movable scroll (35) in the axial direction. The floating member (50) functions as a thrust bearing. The floating member (50) presses the movable scroll (35) in the axial direction against the fixed scroll (31). The drive shaft (40) is inserted into the inner periphery of the floating member (50).

[0045] The floating member (50) includes a scroll support portion (51), a main shaft support portion (52), a recess (53), and a floating-side contact surface (54).

[0046] The scroll support part (51) is cylindrical and constitutes an upper part of the floating member (50). The main shaft support part (52) is cylindrical and constitutes a lower part of the floating member (50). The outer diameter of the scroll support part (51) is larger than the outer diameter of the main shaft support part (52). The inner diameter of the scroll support part (51) is larger than the inner diameter of the main shaft support part (52). The scroll support part (51) and the main shaft support part (52) are connected to each other in the axial direction (up and down direction).

[0047] The scroll support portion (51) of the floating member (50) is located directly below the movable scroll (35). The recess (53) is provided in the center of the upper surface (front surface) of the scroll support portion (51) of the floating member (50). The floating-side contact surface (54) is provided on the upper surface (front surface) of the floating member (50) on the radially outer periphery side of the recess (53). In other words, the recess (53) is provided on the upper surface (front surface) of the floating member (50) on the radially inner periphery side of the floating-side contact surface (54).

[0048] The recess (53) is recessed downward from the upper surface (front surface) of the floating member (50) to form a crank chamber (55). The recess (53) (crank chamber (55)) is substantially circular when viewed in the axial direction. The crank chamber (55) accommodates the boss portion (38) of the movable scroll (35). The floating-side contact surface (54) is ring-shaped when viewed in the axial direction and surrounds the recess (53) (crank chamber (55)). The floating-side contact surface (54) comes into contact with the scroll-side contact surface (39) of the movable scroll (35).

[0049] When the scroll-side contact surface (39) of the movable scroll (35) and the floating-side contact surface (54) of the floating member (50) come into contact with each other, the crank chamber (55) is sealed from the surroundings. An outer space (A) is formed between the inner peripheral wall of the casing (20) and the outer peripheral end of the floating-side contact surface (54) of the floating member (50) in the radial direction outer circumferential side. The outer space (A) is a part of the low-pressure space (Sa).

[0050] When the scroll-side contact surface (39) of the movable scroll (35) and the floating-side contact surface (54) of the floating member (50) come into contact with each other, the crank chamber (55) and the outer space (A) are partitioned from each other by the scroll-side contact surface (39) and the floating-side contact surface (54).

[0051] The floating member (50) is provided with a partition wall (58) formed from a solid portion of the scroll support portion (51). The partition wall (58) extends in the axial direction (up and down direction). The partition wall (58) separates the crank chamber (55) from the outer space (A).

[0052] The floating-side contact surface (54) forms the upper surface of the partition wall (58). The crank chamber (55) is disposed radially inward from the partition wall (58) (the floating-side contact surface (54)). The outer space (A) is disposed radially outward from the partition wall (58) (the floating-side contact surface (54)).

[0053] As will be described in detail later, the floating member (50) is provided with a communication passage (59) that communicates between the crank chamber (55) and the outer space (A).

[0054] A first annular groove (56) for accommodating a seal member (such as an O-ring, not shown) is formed in the outer circumferential surface of the scroll support portion (51) near the lower end thereof.

[0055] A through hole penetrating in the axial direction (vertical direction) is provided on the inner peripheral side of the main shaft support portion (52). A bearing (52a) is fitted into the through hole of the main shaft support portion (52). The main shaft portion (41) of the drive shaft (40) is rotatably (slidably) supported by the main shaft support portion (52) of the floating member (50) via the bearing (52a). The floating member (50) is concentric with the main shaft portion (41) of the drive shaft (40).

[0056] A second annular groove (57) for accommodating a seal member (such as an O-ring, not shown) is formed near the upper end of the outer circumferential surface of the spindle support portion (52).

[0057] (Frame) The frame (60) has a cylindrical shape extending in the axial direction (vertical direction). The frame (60) is provided in the casing (20) below the floating member (50) and above the motor (70). The frame (60) is fixed to the inner circumferential surface of the casing (20) in the low-pressure space (Sa). The frame (60) is fixed to the casing (20) by using a fastener or by press-fitting.

[0058] The frame 60 has a fixed portion 61 and a protruding portion 62. The fixed portion 61 is cylindrical and constitutes the outer peripheral portion of the frame 60. The protruding portion 62 is cylindrical and constitutes the inner peripheral portion and lower portion of the frame 60.

[0059] The outer peripheral surface of the fixed portion (61) is fixed to the inner peripheral surface of the casing (20) by, for example, a fastener (not shown) etc. The inner peripheral surface of the fixed portion (61) faces radially toward the lower end of the outer peripheral surface of the scroll support portion (51) of the floating member (50) (a portion including the first annular groove (56)).

[0060] The protruding portion (62) protrudes inward from the inner peripheral surface of the fixed portion (61). A through hole penetrating in the axial direction (vertical direction) is provided on the inner peripheral side of the protruding portion (62). The main shaft support portion (52) of the floating member (50) supporting the main shaft portion (41) of the drive shaft (40) is inserted into the through hole of the protruding portion (62).

[0061] The inner circumferential surface of the protrusion (62) faces radially toward the upper end of the outer circumferential surface of the main shaft support portion (52) of the floating member (50) (a portion including the second annular groove (57)).

[0062] An upper surface of the protruding portion (62) faces the lower surface of the scroll support portion (51) of the floating member (50). A third annular groove (63) for accommodating a sealing member (e.g., an O-ring, not shown) is formed in the upper surface of the protruding portion (62) near the inner periphery.

[0063] (Motor) The motor (70) is provided below the frame (60) and above the lower bearing member (80) in the casing (20). The motor (70) drives the compression mechanism (30) by rotating the drive shaft (40). The motor (70) has a rotor core (71) as a rotor, and a stator core (72) as a stator.

[0064] The rotor core (71) is cylindrical and extends in the axial direction (vertical direction). The main shaft portion (41) of the drive shaft (40) is inserted and fixed to the inner peripheral side of the rotor core (71). The stator core (72) is cylindrical and extends in the axial direction (vertical direction). The stator core (72) is fixed to the inner peripheral surface of the casing (20). The stator core (72) is disposed so as to surround the rotor core (71) from the outer peripheral side. There is a predetermined gap between the stator core (72) and the rotor core (71) in the radial direction. The rotor core (71) is rotatably inserted into the inner peripheral side of the stator core (72).

[0065] (Lower bearing member) The lower bearing member (80) has a generally cylindrical shape extending in the axial direction (vertical direction). The lower bearing member (80) is provided in the casing (20) between the motor (70) and the oil reservoir (24) (the lower bottom portion (20a) of the casing (20)). The lower bearing member (80) is fixed to the inner circumferential surface of the casing (20). The lower bearing member (80) has a cylindrical portion (81) and a protruding portion (82). The cylindrical portion (81) is cylindrical. The protruding portion (82) protrudes outward from the outer circumferential surface of the cylindrical portion (81).

[0066] A bearing (81a) is fitted on the inner periphery of the cylindrical portion (81). The main shaft portion (41) of the drive shaft (40) is rotatably (slidably) supported by the lower bearing member (80) via the bearing (81a). The protrusion (82) is fixed to the inner periphery of the casing (20).

[0067] (Oil pump) The oil pump (90) is provided at the lower end of the main shaft portion (41) of the drive shaft (40). A nozzle (91) of the oil pump (90) is immersed in the lubricating oil (L) stored in the oil reservoir (24) in the lower bottom portion (20a) of the casing (20). The oil pump (90) draws up the lubricating oil (L) from the oil reservoir (24). The lubricating oil (L) is supplied to each sliding portion of the scroll compressor (10) through an oil passage (43) of the drive shaft (40).

[0068] Sliding parts in the scroll compressor (10) include between the bearing (38a) of the boss portion (38) of the movable scroll (35) and the eccentric shaft portion (42) of the drive shaft (40), between the bearing (52a) of the main shaft support portion (52) of the floating member (50) and the main shaft portion (41) of the drive shaft (40), and between the bearing (81a) of the cylindrical portion (81) of the lower bearing member (80) and the main shaft portion (41) of the drive shaft (40).

[0069] Another sliding part in the scroll compressor (10) is a sliding part (contact part) between a scroll-side contact surface (39) of the movable scroll (35) and a floating-side contact surface (54) of the floating member (50). The sliding part between the scroll-side contact surface (39) and the floating-side contact surface (54) is connected to a crank chamber (55). An oil passage (43) of the drive shaft (40) communicates between the crank chamber (55) and the oil reservoir (24).

[0070] The lubricating oil (L) is pumped up from the oil reservoir (24) by the oil pump (90), passes through the oil passage (43) of the drive shaft (40), flows into the crank chamber (55), and is then supplied to the sliding portion between the scroll side contact surface (39) and the floating side contact surface (54) via the crank chamber (55).

[0071] (Compressor operation) The operation of the scroll compressor (10) will be described. When the motor (70) is driven, the drive shaft (40) rotates to drive the movable scroll (35) of the compression mechanism (30). The movable scroll (35) revolves around the axis (41a) of the main shaft portion (41) of the drive shaft (40) while its rotation is restricted. A low-pressure working fluid (e.g., low-pressure refrigerant gas) flows from the suction pipe (22) into a low-pressure space (Sa) in the casing (20), is sucked into the compression chamber (C) of the compression mechanism (30) through the suction port (34a), and is compressed to become a high-pressure working fluid (e.g., high-pressure refrigerant gas). The high-pressure working fluid flows from the compression chamber (C) of the compression mechanism (30) through the discharge port (32a) to the high-pressure space (Sb), and is discharged to the outside of the casing (20) (e.g., the condenser (2) of the refrigerant circuit (1a)) through the discharge pipe (23).

[0072] A part of the working fluid compressed in the compression chamber (C) and brought to a high pressure is supplied through a fluid passage (not shown) to a first space (S1) between the second annular groove (57) of the floating member (50) and the third annular groove (63) of the frame (60). The high pressure generated in the first space (S1) pushes the floating member (50) axially upward, thereby pressing the movable scroll (35) axially upward against the fixed scroll (31).

[0073] A part of the working fluid that has become an intermediate pressure (a pressure intermediate between low and high pressure) while being compressed in the compression chamber (C) is supplied to the second space (S2) between the first annular groove (56) of the floating member (50) and the third annular groove (63) of the frame (60) through a fluid passage (not shown). The intermediate pressure generated in the second space (S2) pushes the floating member (50) axially upward, thereby pressing the movable scroll (35) axially upward against the fixed scroll (31).

[0074] (Oil film rupture) Fig. 3 is a front cross-sectional view showing the periphery of the crank chamber (55) and the outer space (A) shown in Fig. 2. When high pressure or intermediate pressure is supplied to the back side (lower side) of the floating member (50), the floating member (50) axially supports the movable scroll (35) so as to press the movable scroll (35) against the fixed scroll (31) in the axial direction.

[0075] The floating member (50) is not directly fixed to the casing (20) and is freely swingable relative to the casing (20), and is therefore able to tilt in response to the overturning of the movable scroll (35).

[0076] The floating-side contact surface (54) of the floating member (50) can suitably support the scroll-side contact surface (39) of the movable scroll (35) while being in contact with the scroll-side contact surface (39) of the movable scroll (35) with almost no gap therebetween.

[0077] Lubricating oil (L) is supplied from the crank chamber (55) to the sliding portion between the scroll side contact surface (39) of the movable scroll (35) and the floating side contact surface (54) of the floating member (50) (see arrow (L) in Figure 3), forming an oil film.

[0078] Since the working fluid (G) is present in the crank chamber (55), a portion of the working fluid (G) may be mixed with the lubricating oil (L) supplied from the crank chamber (55) to the sliding portion between the scroll side contact surface (39) and the floating side contact surface (54).

[0079] If the working fluid (G) is mixed with the lubricating oil (L), the oil film is likely to break at the sliding portion between the scroll-side contact surface (39) and the floating-side contact surface (54). The oil film break is mainly caused by a foaming phenomenon in which the working fluid (G) dissolved in the lubricating oil (L) boils and bubbles.

[0080] The oil film rupture can cause poor lubrication or seizure in the sliding portion between the scroll side contact surface (39) and the floating side contact surface (54).

[0081] As described above, since the floating member (50) tilts following the overturning of the movable scroll (35), there is almost no gap between the scroll-side contact surface (39) and the floating-side contact surface (54). Therefore, the working fluid (G) present in the crank chamber (55) cannot pass between the scroll-side contact surface (39) and the floating-side contact surface (54) and cannot escape to the outer space (A).

[0082] The oil film rupture at the sliding portion between the scroll side contact surface (39) and the floating side contact surface (54) is a problem that occurs due to a special structure (float housing structure) in which the floating member (50) follows the upset of the movable scroll (35).

[0083] In the scroll compressor (10) of this embodiment, the following method is used to prevent the oil film from breaking in the sliding portion between the scroll side contact surface (39) of the movable scroll (35) and the floating side contact surface (54) of the floating member (50).

[0084] (Communication path) Fig. 4 shows a plan view of the floating-side contact surface (54) of the floating member (50) as seen from above in the axial direction. As shown in Figs. 3 and 4, the floating member (50) is provided with a communication passage (59). The communication passage (59) connects the crank chamber (55) and the outer space (A) to each other.

[0085] The communication passage (59) is constituted by a groove (59a). There is one groove (59a). The groove (59a) is provided in the floating-side contact surface (54) of the floating member (50). The groove (59a) extends in the radial direction between the crank chamber (55) (the recess (53)) on the inner periphery side and the outer space (A) on the outer periphery side.

[0086] The groove (59a) is disposed on the radially opposite side of the drive shaft (40) with respect to a suction port (34a) (shown by a two-dot chain line) to the compression chamber (C) of the compression mechanism (30), with the drive shaft (40) in between. Preferably, the groove (59a) is disposed on the diametrically opposite side of the drive shaft (40) with respect to the suction port (34a), at an angle of 180°.

[0087] 5 shows the cross-sectional shape of the groove (59a) serving as the communication passage (59). The groove (59a) is recessed downward with respect to the floating-side contact surface (54) of the floating member (50). In this example, the cross-sectional shape of the groove (59a) is rectangular. The groove (59a) preferably has a cross-sectional area large enough for the working fluid (G) to flow through. The groove (59a) preferably has a width of 1 mm or more, more preferably 5 mm or more, and even more preferably 10 mm or more. The groove (59a) preferably has a depth of 1 mm or more, more preferably 5 mm or more, and even more preferably 10 mm or more.

[0088] (Action and effect) In the scroll compressor (10) according to this embodiment, the working fluid (G) present in the crank chamber (55) flows through the communication passage (59) (the groove portion (59a)) into the outer space (A) (see arrow (G)). The working fluid (G) is less likely to mix with the lubricating oil (L) supplied from the crank chamber (55) to the sliding portion between the scroll side contact surface (39) and the floating side contact surface (54).

[0089] The scroll compressor (10) according to this embodiment can prevent an oil film from being broken in the sliding portion between the scroll-side contact surface (39) of the movable scroll (35) and the floating-side contact surface (54) of the floating member (50). This can prevent poor lubrication and seizure in the sliding portion between the scroll-side contact surface (39) and the floating-side contact surface (54).

[0090] The scroll compressor (10) according to this embodiment can solve the problem of oil film rupture at the sliding portion between the scroll side contact surface (39) and the floating side contact surface (54), which is caused by a special structure (float housing structure) in which the floating member (50) follows the overturning of the movable scroll (35).

[0091] By providing the groove (59a) in the floating side contact surface (54), the communication passage (59) can be easily formed.

[0092] By arranging the communication passage (59) (groove portion (59a)) on the radially opposite side of the suction port (34a) with the drive shaft (40) therebetween, the communication passage (59) (groove portion (59a)) can be located away from the suction port (34a). This makes it possible to prevent the lubricating oil (L) from mixing with the working fluid (G) sucked into the compression chamber (C) of the compression mechanism (30) through the suction port (34a).

[0093] The oil passage (43) of the drive shaft (40) connects the crank chamber (55) to the oil reservoir (24) in the lower floor (20a) of the casing (20). Lubricating oil (L) can be introduced from the oil reservoir (24) in the lower floor (20a) of the casing (20) to the crank chamber (55) through the oil passage (43) of the drive shaft (40).

[0094] <Second embodiment> A scroll compressor (10) according to a second embodiment will be described. In the following description, the same components as those in the above embodiment will be denoted by the same reference numerals, and detailed description will be omitted. Fig. 6 is a front cross-sectional view of the crank chamber (55) and the outer space (A) according to the second embodiment. Fig. 7 shows the cross-sectional shape of a through hole (59b) serving as a communication passage (59) according to the second embodiment.

[0095] As shown in Figs. 6 and 7, the floating member (50) is provided with a partition wall (58) formed by the solid portion of the scroll support portion (51). The partition wall (58) extends in the axial direction (up and down direction). The partition wall (58) separates the crank chamber (55) from the outer space (A). The floating-side contact surface (54) forms the upper surface of the partition wall (58). The crank chamber (55) is disposed radially inward from the partition wall (58) (the floating-side contact surface (54)). The outer space (A) is disposed radially outward from the partition wall (58) (the floating-side contact surface (54)).

[0096] The communication passage (59) is defined by a through hole (59b) formed in the partition wall (58). The through hole (59b) passes through the partition wall (58). There is one through hole (59b).

[0097] The through hole (59b) extends radially between the crank chamber (55) (the recess (53)) on the inner periphery side and the outer space (A) on the outer periphery side. The through hole (59b) is disposed on the radially opposite side of the drive shaft (40) from the suction port (34a) to the compression chamber (C) of the compression mechanism (30), with the drive shaft (40) therebetween.

[0098] The through hole (59b) is disposed below the floating-side contact surface (54) of the floating member (50). The through hole (59b) is disposed above the lower end of the crank chamber (55) that houses the boss portion (38). The through hole (59b) is preferably disposed above the center of the crank chamber (55) in the axial direction (vertical direction). The through hole (59b) is preferably disposed above the oil level of the lubricating oil (L) that has flowed into the crank chamber (55).

[0099] In this example, the cross-sectional shape of the through hole (59b) is circular. The through hole (59b) preferably has a cross-sectional area large enough to allow the working fluid (G) to flow through. The diameter of the through hole (59b) is preferably 1 mm or more, more preferably 5 mm or more, and even more preferably 10 mm or more. The other configurations are the same as those of the first embodiment.

[0100] In the scroll compressor (10) of this embodiment, the communication passage (59) can be easily formed by forming the through hole (59b) in the partition wall (58) separating the crank chamber (55) from the outer space (A).

[0101] <Other embodiments> Other embodiments will now be described.

[0102] The size of the communication passage 59 is not limited to the above. For example, the groove width and depth of the groove 59a may be 1 mm or less. The diameter of the through hole 59b may be 1 mm or less.

[0103] The cross-sectional shape of the communication passage (59) is not limited to the above. For example, the cross-sectional shape of the groove portion (59a) may be a polygon other than a rectangle or a circle. The cross-sectional shape of the through hole (59b) may be a polygon.

[0104] The communication passage (59) may be located on the same radial side of the drive shaft (40) as the suction port (34a), or may be located at another location.

[0105] The number of the communication passage (59) is not limited to one, and a plurality of communication passages (59) may be provided.

[0106] The communication passage (59) may be configured in a form other than the groove (59a) and the through hole (59b) (for example, a pipe, etc.).

[0107] In the above embodiment, the outer space (A) is formed between the outer peripheral end of the floating-side contact surface (54) of the floating member (50) and the inner peripheral wall of the casing (20), but is not limited thereto. For example, the outer space (A) may be formed between the outer peripheral end of the floating-side contact surface (54) of the floating member (50) and the frame (60) or other members fixed to the casing (20). The outer space (A) may not be part of the low pressure space (Sa), but may be part of the high pressure space (Sb) or part of the intermediate pressure space.

[0108] The scroll compressor (10) may be disposed horizontally, i.e., the axial direction (Z) may be horizontal.

[0109] The scroll compressor (10) does not have to be applied to the refrigeration system (1) and may be used, for example, as a standalone unit.

[0110] Although the embodiments have been described above, it will be understood that various modifications of form and details are possible without departing from the spirit and scope of the claims. Elements of the above-mentioned embodiments, modifications, and other embodiments may be appropriately combined or substituted. [Explanation of symbols]

[0111] Z-axis direction (vertical direction) R Radial direction Ro Outer circumference Ri inner side T circumferential direction C Compression chamber A outside space L Lubricating oil (oil) G Working fluid 1 Refrigeration equipment 10 Scroll Compressor 20 Casing 20a lower bottom 24 Oil Reservoir 30 Compression Mechanism 31 Fixed Scroll 34a Inlet 35 Movable Scroll 38 Boss 39 Scroll side contact surface 40 Drive shaft 40a Inside 41 Main shaft part 42 Eccentric shaft part 43 Oil passage 50 Floating member 53 Recess 54 Floating side contact surface 55 Crankcase 58 Partition Wall 59 Communication path 59a Groove 59b Through hole 60 frames 70 Motor 80 Lower bearing member 90 Oil Pump

Claims

1. a compression mechanism (30) having a fixed scroll (31) and a movable scroll (35); a drive shaft (40) having a main shaft portion (41) and an eccentric shaft portion (42) eccentric with respect to the main shaft portion (41); a floating member (50) that presses the movable scroll (35) against the fixed scroll (31), the movable scroll (35) includes a scroll-side contact surface (39) that contacts the floating member (50), and a boss portion (38) that is provided on an inner peripheral side (Ri) of the scroll-side contact surface (39), extends toward the floating member (50), and is connected to the eccentric shaft portion (42), the floating member (50) includes a floating-side contact surface (54) that comes into contact with the movable scroll (35), and a recess (53) that is provided on an inner peripheral side (Ri) of the floating-side contact surface (54) and forms a crank chamber (55) that accommodates the boss portion (38), An outer space (A) is formed on the outer circumferential side (Ro) of the floating-side contact surface (54), The floating member (50) is provided with a communication passage (59) that communicates between the crank chamber (55) and the outer space (A). Scroll compressor.

2. The communication passage (59) is formed of a groove portion (59a) provided in the floating-side contact surface (54).

2. The scroll compressor according to claim 1.

3. The floating member (50) is provided with a partition wall (58) which separates the crank chamber (55) from the outer space (A), The communication passage (59) is formed as a through hole (59b) formed in the partition wall (58).

2. The scroll compressor according to claim 1.

4. The communication passage (59) is disposed on the opposite side of the drive shaft (40) in the radial direction (R) of the drive shaft (40) with respect to a suction port (34a) to the compression mechanism (30).

2. The scroll compressor according to claim 1.

5. a casing (20) that houses the compression mechanism (30), the drive shaft (40), and the floating member (50), The drive shaft (40) extends in the vertical direction (Z), An oil reservoir (24) for storing oil (L) is provided in a lower bottom portion (20a) of the casing (20), The drive shaft (40) is provided with an oil passage (43) extending in the vertical direction (Z) through an interior (40a) of the drive shaft (40), The oil passage (43) communicates the crank chamber (55) with the oil reservoir (24).

2. The scroll compressor according to claim 1.

6. The scroll compressor (10) according to any one of claims 1 to 5, Refrigeration equipment.

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