The present disclosure relates to a scroll compressor and a refrigeration apparatus.
Japanese Unexamined Patent Publication No. 2020-193576 discloses a scroll compressor. The scroll compressor described in Japanese Unexamined Patent Publication No. 2020-193576 includes a compression mechanism having a fixed scroll and a movable scroll and a floating member. The floating member is pushed up when high pressure and intermediate pressure act on a back surface of the floating member. This causes the floating member to press the movable scroll against the fixed scroll.
If the movable scroll tilts, the floating member is inclined to follow the tilt of the movable scroll, possibly keeping the floating member in close contact with the movable scroll without any clearance. As a result, oil is less likely to flow into a space between the movable scroll and the floating member, causing poor lubrication. Thus, a contact portion between the movable scroll and the floating member is seized, and bearing reliability of the floating member may decrease.
An object of the present disclosure is to keep the bearing reliability of the floating member from deteriorating although the movable scroll tilts and the floating member follows the tilt of the movable scroll.
A first aspect is directed to a scroll compressor. The scroll compressor includes a compression mechanism having a fixed scroll and a movable scroll, and a floating member supporting the movable scroll. The floating member includes an opposing surface opposed to a back surface of the movable scroll. The back surface of the movable scroll includes a first portion facing an inner portion of the opposing surface of the floating member, and a second portion facing an outer portion of the opposing surface of the floating member. A clearance is present between the inner portion of the opposing surface and the first portion of the back surface.
As illustrated in
Embodiments of the present disclosure will be described in detail below with reference to the drawings. The present disclosure is not limited to the embodiments shown below, and various changes can be made within the scope without departing from the technical concept of the present disclosure. Each of the drawings is intended to illustrate the present disclosure conceptually, and dimensions, ratios, or numbers may be exaggerated or simplified as necessary for the sake of ease of understanding.
Exemplary embodiments will be described in detail below based on the drawings.
A scroll compressor (1) will be described with reference to
As illustrated in
The casing (10) is in the shape of a vertically long cylinder with both ends closed. The casing (10) houses the compression mechanism (20) and the electric motor (30). The drive shaft (40) extending in the casing (10) in an axial direction (Y) (a vertical direction in
A partitioning member (11) is provided in an upper portion of the casing (10). The partitioning member (11) divides an internal space of the casing (10) into two spaces. A space above the partitioning member (11) constitutes a first space (S1). A space below the partitioning member (11) constitutes a second space (S2).
The casing (10) is provided with a suction pipe (not shown) and a discharge pipe (12). The suction pipe penetrates a barrel of the casing (10) in a radial direction (X) and communicates with the second space (S2). The suction pipe introduces a low-pressure fluid (e.g., a gas refrigerant) into the second space (S2). The discharge pipe (12) penetrates an upper portion of the casing (10) in the radial direction (X) to communicate with the first space (S1). The discharge pipe (12) leads a high-pressure fluid in the first space (S1) to the outside of the casing (10).
The compression mechanism (20) includes a fixed scroll (21) and a movable scroll (26). The fixed scroll (21) is fixed to the frame (60). The movable scroll (26) is disposed between the floating member (50) and the fixed scroll (21). The movable scroll (26) is configured to mesh with the fixed scroll (21) and rotate eccentrically relative to the fixed scroll (21).
The fixed scroll (21) is disposed on one side (in this example, an upper side) of the frame (60) in the axial direction (Y). The fixed scroll (21) includes a fixed end plate (22), a fixed wrap (23), and an outer peripheral wall (24).
The fixed end plate (22) has a substantially circular plate shape. The fixed wrap (23) is formed in the shape of a spiral wall that shows an involute curve, and protrudes from a front surface (a lower surface in this example) of the fixed end plate (22). The outer peripheral wall (24) surrounds the outer periphery of the fixed wrap (23), and protrudes from the front surface of the fixed end plate (22). A distal end face (a lower end face in this example) of the fixed wrap (23) is substantially flush with a distal end face of the outer peripheral wall (24).
An inlet (not shown) is formed in the outer peripheral wall (24) of the fixed scroll (21). The inlet communicates with the second space (S2). The fixed end plate (22) of the fixed scroll (21) is provided with an outlet (25) penetrating a center portion of the fixed end plate (22) in a thickness direction.
The movable scroll (26) includes a movable end plate (27), a movable wrap (28), and a boss (29).
The movable end plate (27) has a substantially circular plate shape. The movable wrap (28) is formed in the shape of a spiral wall that shows an involute curve, and protrudes from a front surface (an upper surface in this example) of the movable end plate (27). The boss (29) is formed in a cylindrical shape, and disposed at a center portion of a back surface (270) (a lower surface in this example) of the movable end plate (27). The movable wrap (28) of the movable scroll (26) meshes with the fixed wrap (23) of the fixed scroll (21).
This configuration forms a compression chamber (S20) between the fixed scroll (21) and the movable scroll (26). The compression chamber (S20) is a space for compressing a fluid. The compression chamber (S20) is configured to compress a fluid sucked through the suction pipe, the second space (S2), and the inlet, and discharge the compressed fluid through the outlet (25).
The electric motor (30) is housed in the casing (10), and is disposed below the compression mechanism (20). The electric motor (30) includes a stator (31) and a rotor (32). The stator (31) is substantially in the shape of a cylinder, and is fixed to the casing (10). The rotor (32) is rotatably inserted into, and runs through, the stator (31). The drive shaft (40) is inserted in the rotor (32) and fixed to an inner periphery of the rotor (32).
The drive shaft (40) has a main shaft portion (41) and an eccentric shaft portion (42). The main shaft portion (41) extends in the axial direction (Y) (the vertical direction in this embodiment). The axial direction (Y) is parallel to a direction in which the axis of the main shaft portion (41) of the drive shaft (40) extends. The eccentric shaft portion (42) is provided at an upper end of the main shaft portion (41). The eccentric shaft portion (42) has a smaller outer diameter than the main shaft portion (41). The eccentric shaft portion (42) has an axis decentered by a predetermined distance with respect to the axis of the main shaft portion (41). The drive shaft (40) is connected to the movable scroll (26) from the other side (Y2) in the axial direction (Y) (from a lower side in this embodiment).
The floating member (50) is formed substantially in a cylindrical shape. The floating member (50) is supported in a swingable manner. The floating member (50) includes a scroll support (51), a shaft support (53), and a coupling portion (55). The floating member (50) is an example of a thrust bearing of the present invention.
The scroll support (51) is a substantially cylindrical portion that makes contact with the back surface (270) of the movable scroll (26). The scroll support (51) supports the movable scroll (26). A first annular groove (52) that houses an O-ring (not shown) is formed in an outer wall of the scroll support (51) near its lower end.
The shaft support (53) is a substantially cylindrical portion having a smaller inner diameter than the scroll support (51). The shaft support (53) rotatably supports the main shaft portion (41) of the drive shaft (40). A second annular groove (54) that houses an O-ring (not shown) is formed in an outer wall of the shaft support (53) near its lower end.
The coupling portion (55) is a substantially ring-shaped portion. The coupling portion (55) couples the lower end of the scroll support (51) and the upper end of the shaft support (53) to each other.
The floating member (50), the movable scroll (26), and the fixed scroll (21) are arranged in this order toward the one side (Y1) in the axial direction (Y).
The frame (60) is substantially cylindrically shaped. The frame (60) is fixed to the casing (10) in the second space (S2) by, for example, press fitting. The frame (60) includes a fixing portion (61) and a protrusion (62).
The fixing portion (61) is a substantially cylindrical portion. An outer peripheral surface of the fixing portion (61) is fixed to the casing (10). The fixed scroll (21) is fixed to an upper surface of the fixing portion (61).
The protrusion (62) is a substantially cylindrical or ring-shaped portion. The protrusion (62) protrudes inward in the radial direction (X) from the inner periphery of the fixing portion (61). A third annular groove (63) that houses a seal member (not shown) is formed in an upper surface of the protrusion (62) near its inner periphery.
A through hole (64) is formed inside the protrusion (62) in the radial direction (X). The drive shaft (40) and the shaft support (53) are inserted into the through hole (64). Operation of Scroll Compressor
As illustrated in
A first embodiment of the configuration of the movable scroll (26) and the floating member (50) will be described below with reference to
As illustrated in
The back surface (270) of the movable scroll (26) includes a first portion (271), a second portion (272), and a center portion (273). The first portion (271) faces the inner portion (501) of the floating member (50). The second portion (272) faces the outer portion (502) of the floating member (50). Each of the first portion (271) and the second portion (272) is an annular portion about the drive shaft (40). The second portion (272) is located outward of the first portion (271) in the radial direction (X). The center portion (273) is located inward of the first portion (271) in the radial direction (X). The drive shaft (40) is connected to the center portion (273).
The second portion (272) of the movable scroll (26) and the outer portion (502) of the floating member (50) have planes parallel to each other.
The first portion (271) of the movable scroll (26) has a plane flush with the second portion (272).
The inner portion (501) of the floating member (50) includes an inclined surface (501a) that is inclined to be separated from the first portion (271) of the movable scroll (26). In the first embodiment, the inclined surface (501a) of the inner portion (501) is inclined to be gradually separated from the first portion (271) in the axial direction (Y) as the inclined surface (501a) extends inward in the radial direction (X) (toward the drive shaft (40)).
As illustrated in
When tilting, the movable scroll (26) is inclined with respect to the axial direction (Y) (the axis of the drive shaft (40)) as illustrated in
The inclined surface (501a) is provided for the floating member (50) so that the clearance (U) is kept present although the outer portion (502) of the floating member (50) and the second portion (272) of the movable scroll (26) make surface contact with each other when the movable scroll (26) tilts and the floating member (50) is inclined to follow the tilt of the movable scroll (26). Thus, oil can be supplied through the clearance (U) to form an oil film between the movable scroll (26) and the floating member (50), avoiding poor lubrication. As a result, seizing of the contact portion between the movable scroll (26) and the floating member (50) can be reduced. This can keep the floating member (50) from impairing its function of supporting the movable scroll (26) when the movable scroll (26) tilts.
As illustrated in
When the gas load deforms the movable scroll (26), the outer portion (502) of the floating member (50) makes surface contact with the second portion (272) of the movable scroll (26), and is curved (deformed) along the second portion (272).
When the gas load deforms the movable scroll (26), the first portion (271) of the movable scroll (26) is curved toward the floating member (50), with a clearance (U) kept present between the first portion (271) and the inclined surface (501a) of the floating member (50). Thus, although the gas load deforms the movable scroll (26) when the movable scroll (26) tilts, oil can be supplied through the clearance (U) to form an oil film between the movable scroll (26) and the floating member (50). This can keep the floating member (50) from impairing its function of supporting the movable scroll (26).
Referring to
As illustrated in
As illustrated in
With this configuration of the second embodiment, the clearance (U) can be kept present between the first portion (271) and the step portion (501b) of the floating member (50) when the floating member (50) follows the tilt of the movable scroll (26) as illustrated in
Referring to
As illustrated in
As illustrated in
The first portion (271) of the movable scroll (26) includes an inclined surface (271a) that is inclined to be separated from the inner portion (501) of the floating member (50). In the third embodiment, the inclined surface (271a) of the first portion (271) is inclined to be gradually separated from the inner portion (501) in the axial direction (Y) as the inclined surface (271a) extends inward in the radial direction (X) (toward the drive shaft (40)). A clearance (U) is formed between the inclined surface (271a) and the inner portion (501) of the floating member (50). The dimension of the clearance (U) in the axial direction (Y) gradually increases toward the center of the scroll compressor (1).
With this configuration of the third embodiment, the clearance (U) can be kept present between the inclined surface (271a) of the first portion (271) and the floating member (50) when the floating member (50) follows the tilt of the movable scroll (26) as illustrated in
Referring to
As illustrated in
As illustrated in
With this configuration of the fourth embodiment, the clearance (U) can be kept present between the step portion (271b) of the first portion (271) and the floating member (50) when the floating member (50) follows the tilt of the movable scroll (26) as illustrated in
While the embodiments and the variations thereof have been described above, it will be understood that various changes in form and details may be made without departing from the spirit and scope of the claims (e.g., (1) below). The embodiments, the variations, and the other embodiments may be combined and replaced with each other without deteriorating intended functions of the present disclosure.
(1) The first portion (271) of the movable scroll (26) may have one of the step portion (271b) or the inclined surface (271a), and the inner portion (501) of the floating member (50) may have one of the inclined surface (501a) or the step portion (501b).
As described above, the present disclosure is useful for a scroll compressor and a refrigeration apparatus.
Number | Date | Country | Kind |
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2022-052881 | Mar 2022 | JP | national |
This is a continuation of International Application No. PCT/JP2022/048408 filed on Dec. 27, 2022, which claims priority to Japanese Patent Application No. 2022-052881, filed on Mar. 29, 2022. The entire disclosures of these applications are incorporated by reference herein.
Number | Date | Country | |
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Parent | PCT/JP2022/048408 | Dec 2022 | WO |
Child | 18883940 | US |