The present disclosure relates to a scroll compressor provided with a compression mechanism having a fixed scroll and an orbiting scroll, and in particular, to a structure of allowing the compression mechanism to hold an Oldham ring that is a mechanism preventing the orbiting scroll from rotating on its axis.
In conventional scroll compressors, an Oldham ring (100) is typically used to allow revolution of an orbiting scroll (not illustrated) while substantially preventing rotation of the orbiting scroll on its axis, as illustrated in
Patent Document 1 discloses, as a modification of the above structure, a structure in which the keys (102, 103) are disposed so as to protrude radially outwardly from the ring portion (101), as illustrated in
Further, Patent Document 2 discloses, as illustrated in
[Patent Document 1] Japanese Unexamined Patent Publication No. 2010-185462
[Patent Document 2] Japanese Unexamined Patent Publication No. S63-138181
The typical configuration of the Oldham ring (100) shown in
In the configuration of Patent Document 1, as illustrated in
Further, in the configuration of Patent Document 2, as illustrated in
In view of the foregoing background, it is therefore an object of the present invention to prevent the strength of, e.g., a housing and an Oldham ring from decreasing too much while preventing the size of an orbiting scroll facing surface from decreasing too much.
A first aspect of the present disclosure is directed to a scroll compressor including: a housing (23) into which a drive shaft (40) is inserted: an Oldham ring (50) configured to be slidable on the housing (23) by a first key mechanism (51) in a first direction perpendicular to an axial center of drive shaft (40); a fixed scroll (21) fixed to the housing (23); and an orbiting scroll (22) meshing with the fixed scroll (21) and configured to be slidable on the Oldham ring (50) by a second key mechanism (52) in a second direction perpendicular to the axial center of drive shaft (40), the first key mechanism (51) including a first key (54) provided to the Oldham ring (50) and a first key groove (61) formed in the housing (23).
In the scroll compressor, the first key (54) protrudes from the ring portion (53) of the Oldham ring (50) toward the housing (23), and further protrudes in a radially inward direction of the ring portion (53), the housing (23) includes a flange (23a) to which the fixed scroll (21) is fixed and which includes a facing portion (71) having a predetermined thickness and having an orbiting scroll facing surface (70) facing the orbiting scroll (22), and an annular opening (72) formed around the orbiting scroll facing surface (70) and movably housing the ring portion (53), and the first key groove (61) is formed in a position adjacent to a back surface of the facing portion (71) opposite to the orbiting scroll facing surface (70) so as to extend radially inwardly from the annular opening (72). In this configuration, the orbiting scroll facing surface (70) facing the orbiting scroll (22) may be in contact with (slide on) the orbiting scroll (22) or may be spaced apart from (not slide on) the orbiting scroll (22).
According to the first aspect, the first key groove (61) formed in the position adjacent to the back surface of the facing portion (71) engages with the first key (54) of the Oldham ring (50), allowing the Oldham ring (50) to operate. In this configuration, the first key (64) protrudes from the ring portion (53) of the Oldham ring (50) toward the housing (23) and further protrudes in the radially inward direction of the ring portion (53). This can sufficiently increase the area of the sliding surface between the first key (54) and the first key groove (61) to reduce a contact pressure of the key sliding surface. Also, since the first key (54) protrudes in the radially inward direction of the Oldham ring (50), the outer periphery of the housing (23) does not have to be notched, and the moment of the first key (54) can be reduced. Further, the first key groove (61) is formed in the position adjacent to the back side of the orbiting scroll facing surface (70) (in the position adjacent to the back surface of the facing portion (71)), and thus, the first key groove (61) does not hinder the formation of the sealing ring.
A second aspect of the present disclosure is an embodiment of the first aspect. In the second aspect, the first key (54) includes a pair of first keys (54) opposed to each other by 180° on the Oldham ring (50), and an interval (A) between the pair of the first keys (54) is smaller than an outer diameter (B) of the facing portion (71) of the housing (23), and a thickness (C) of the ring portion (53) is larger than a thickness (D) of the facing portion (71) of the housing (23).
The second aspect satisfies the above dimension relationship, making it possible to easily attach the Oldham ring (50) to the housing (23) along an oblique direction, as illustrated in
A third aspect of the present disclosure is an embodiment of the first or second aspect of the present disclosure. In the third aspect, the back surface of the facing portion (71) is a tilted surface (71a) such that a thickness of the facing portion (71) increases toward an inner periphery of the facing portion (71).
According to the third aspect, the back surface of the facing portion (71) is the tilted surface (71a), and thus, when the Oldham ring (50) is attached to the housing (23), the first key (54) can be easily inserted into the first key groove (61).
A fourth aspect of the present disclosure is an embodiment of the first, second, or third aspect of the present disclosure. In the fourth aspect, the first key groove (61) is a groove opened on a hack surface of the flange (23a) of the housing (23).
According to the fourth aspect, the first key (54) engages with the first key groove (61) opened on the back surface of the flange (23a) of the housing (23), allowing the Oldham ring (50) to operate.
A fifth aspect of the present disclosure is an embodiment of the first, second, or third aspect of the present disclosure. In the fifth aspect, the first key groove (61) is a groove opened on an outer peripheral surface of the flange (23a) of the housing (23).
According to the fifth aspect, the first key (54) engages with the first key groove (61) opened on the outer peripheral surface of the flange (23a) of the housing (23), allowing the Oldham ring (50) to operate.
A sixth aspect of the present disclosure is an embodiment of the first, second, or third. aspect of the present disclosure. In the sixth aspect, the facing portion (71) is configured as a separate member different from the housing (23) and fixed to a main body of the housing (23).
According to the sixth aspect, the first key groove (61) is formed by fixing the facing portion (71) configured as a separate member to the main body of the housing (23), and the first key (54) engages with the first key groove 61), allowing the Oldham ring (50) to operate.
According to the first aspect of the present disclosure, the first key (64) protrudes from the ring portion (53) of the Oldham ring (50) toward the housing (23) and further protrudes in the radially inward direction of the ring portion (53). This can sufficiently increase the area of the sliding surface between the first key (54) and the first key groove (61), and reduce a contact pressure of the key sliding surface contributing to preventing insufficient strength of the first key (54) of the Oldham ring (50). Also, the first key (54) protrudes in the direction radially inward of the Oldham ring (50), and the outer periphery of the housing (23) does not have to be notched. This can reduce the moment of the first key (54), and prevent the strength of the Oldham ring (50) from decreasing too much. Further, since the first key groove (61) is formed in the position adjacent to the back side of the orbiting scroll facing surface (70) (in the position adjacent to the back surface of the facing portion (71)), the first key groove (61) does not hinder the formation of the sealing ring, and it is possible to use the seal ring (50) in a configuration in which the first key (54) and the first key groove (61) engage with each other.
According to the second aspect of the present disclosure, the interval (A) between the pair of the first keys (54) is smaller than the outer diameter (B) of the facing portion (71) of the housing (23), and the thickness (C) of the ring portion (53) is larger than the thickness (D) of the facing portion (71) of the housing (23). Thus, as illustrated in
According to the third aspect of the present disclosure, the back surface of the facing portion (71) is the tilted surface (71a), and thus, when the Oldham ring (50) is attached to the housing (23), the first key (54) can be easily inserted into the first key groove (61), improving ease of attachment.
According to the fourth aspect of the present disclosure, the first key groove (61) is a groove opened on the back surface of the flange (23a) of the housing (23), easily forming the first key groove (61).
According to the fifth aspect of the present disclosure, the first key groove (61), which is a groove opened on the outer peripheral surface of the flange (23a) of the housing (23), can be easily formed.
According to the sixth aspect of the present disclosure, the first key groove (61) can be easily formed by fixing the facing portion (71) configured as a separate member to the main body of the housing (23).
Embodiments of the present disclosure will now be described in detail with reference to the drawings.
A scroll compressor according to this embodiment is provided to, e.g., a refrigerant circuit of an air conditioner performing a vapor compression refrigeration cycle, and compresses a low-pressure refrigerant that has been sucked from an evaporator to discharge it into a condenser.
As illustrated in
This casing (10) houses a compression mechanism (20) compressing a refrigerant, and an electric motor (45) driving the compression mechanism (20). The electric motor (45) is disposed below the compression mechanism (20), and is coupled to the compression mechanism (20) through a drive shaft (40) that is a rotational shaft. The electric motor (45) is implemented as a brushless DC motor controlled by an inverter to adjust a rotational speed to be variable.
A discharge pipe (5) passes through and is attached to the upper end plate (12) that is a top of the casing (10). This discharge pipe (15) has its terminal end (the lower end in the figure) connected to the compression mechanism (20). A suction pipe (14) passes through and is attached to the body (11) of the casing (10). This suction pipe (14) has its terminal end (the right end in the figure) open toward a space between the compression mechanism (20) and the electric motor (45) in the casing (10).
The drive shaft (40) is disposed on the vertical center line of the easing (10). The drive shaft (40) is a crank shaft including a main shaft portion (41) and an eccentric portion (42). The eccentric portion (42) has a smaller diameter than the main shaft portion (41), and is formed on the upper surface of the main shaft portion (41). The eccentric portion (42) is eccentric from the axial center of the main shaft portion (41) by a predetermined dimension, and constitutes an eccentric pin.
A lower bearing holder (48) is fixed to a portion adjacent to the lower end of the body (11) of the casing (10). This lower bearing holder (48) rotatably supports the lower end of the main shaft portion (41) of the drive shaft (40) through a sliding bearing (48a).
The interior of the drive shaft (40) is provided with an oil supply passage (44) extending vertically. The lower end of the main shaft portion (41) is provided with an oil supply pump (43). This oil supply pump (43) sucks refrigerating machine oil from the bottom of the casing (10). The refrigerating machine oil passes through the oil supply passage (44) of the drive shaft (40) to be supplied to the sliding portion of the compression mechanism (20) and the bearing of the drive shaft (40).
The electric motor(45) is comprised of a stator (46) and a rotor (47). The stator (46) is fixed to the body (11) of the casing (10). The rotor (47) is coupled to the main shaft portion (41) of the drive shaft (40) to drive the drive shaft (40) in rotation.
The compression mechanism (20) includes a fixed scroll (21), an orbiting scroll (22), and a housing (23) fixing and supporting the fixed scroll (21). The fixed scroll (21) and the orbiting scroll (22) respectively include spiral laps (21b, 22b) meshing with each other on end plates (21a, 22a). The compression mechanism (20) is configured such that the orbiting scroll (22) rotates eccentrically relative to the fixed scroll (21).
The housing (23) is comprised of a main body (flange) (23a) and a bearing holder (23b). The main body (23a) is formed to be vertically continuous with the bearing holder (23b), and the main body (23a) is fitted into and coupled to the body (11) of the casing (10). The bearing holder (23b) has a smaller diameter than the main body (23a), and protrudes downward from the main body (23a). The bearing holder (23b) rotatably supports the main shaft portion (41) of the drive shaft (40) through a sliding bearing (23c).
The fixed scroll (21) is comprised of a fixed end plate (21a), a fixed lap (21b), and an edge portion (21c). The fixed end plate (21a) is formed to have a substantially disk shape. The fixed lap (21b) stands near the middle portion of the lower surface of the fixed end plate 21a), and is integrally formed with the fixed end plate (21a). The fixed lap (21b) is formed to have a spiral wall shape with a constant height. The edge portion (21c) is a wall extending downward from the outer peripheral portion of the fixed end plate (21a), and has a lower surface overlapping with the upper surface of the main body (23a) of the housing (23) to be fixed to the housing (23).
The orbiting scroll (22) is comprised of an orbiting end plate (22a), an orbiting lap (22b), and a boss (22c). The orbiting end plate (22a) is formed to have a substantially disk shape. The orbiting lap (22b) stands on upper surface of the orbiting end plate (22a), and is integrally formed with the orbiting end plate (22a). The orbiting lap (22b) is formed to have a spiral wall shape with a constant height, and to mesh with the fixed lap (21b) of the fixed scroll (21).
The upper end of the fixed end plate (21a) is provided with a depression (21g), and a discharge cover (27) is attached to the upper surface of the fixed end plate (21a) to cover the depression (21g). A space where the depression (21g) is covered with the discharge cover (27) is a discharge chamber (28) communicating with the discharge pipe (15). A middle lower portion of the fixed end plate a) is provided with a discharge port (26) communicating with the discharge chamber (28), and the discharge port (26) communicates with a compression chamber formed between the fixed lap (21b) and the orbiting lap (22b). In this embodiment, in the interior of the casing (10), both upper and lower spaces (16) and (17) of the housing (23) are low-pressure spaces filled with a low-pressure refrigerant.
The boss (22c) extends downwardly from the lower surface of the orbiting end plate (22a), and integrally formed with the orbiting end plate (22a). The eccentric portion (42) of the drive shaft (40) is inserted into the boss (22c) through a sliding bearing (22d). Therefore, if the drive shaft (40) rotates, the orbiting scroll (22) revolves around the axial center of the main shaft portion (41). The revolution radius of the orbiting scroll (22) is the same as the eccentricity of the eccentric portion (42), i.e., a distance from the axial center of the main shaft portion (41) to the axial center of the eccentric portion (42).
The orbiting end plate (22a) is disposed in a first recess (23d) provided to the upper end of the housing (23). The boss (22c) is disposed in a second recess (a crank chamber) (23e) provided to the main body (23a) of the housing (23). The Oldham ring (50) is disposed between the orbiting end plate (22a) and the housing (23) to prevent the orbiting scroll (22) from rotating on its axis.
The Oldham ring (50) has a ring portion (53). The first key mechanism (51) is comprised of a first key (54) provided to the ring portion (53) and a first key groove (61) formed in the housing (23). The second key mechanism (52) is comprised of a second key (55) provided to the ring portion (53) and a second key groove (62) formed in the orbiting scroll (22).
A reciprocating motion of the first key (54) in the first key groove (61) and a reciprocating motion of the second key (55) in the second key groove (62) are synthesized to allow the orbiting scroll (22) engaging with the second key (55) to rotate on its axis, not to revolve around the fixed scroll (21) fixed to the housing (23).
As illustrated in
As illustrated in
The first key (54) includes a pair of first keys (54) opposed to each other by 180° on the Oldham ring (50). The second key (55) includes a pair of second keys (55) opposed to each other by 180° on the Oldham ring (50) so as to be at right angles with the first key (54).
In this embodiment, in
According to such a configuration, as illustrated in
Next, it will be described how the scroll compressor (1) stated above is operated.
First, if the electric motor (45) is driven, the drive shaft (40) rotates and the orbiting scroll (22) revolves relative to the fixed scroll (21). At that time, the Oldham ring (50) prevents the fixed scroll (21) from rotating on its axis.
Along with the revolution of the orbiting scroll (22), volumes of the compression chambers (25a. 25b) increase and decrease repeatedly and periodically. In the compression chambers (25a, 25b), the refrigerant in the refrigerant circuit is sucked from the suction pipe (14) through a suction passage (not shown) and the suction port (29) into the compression chambers (25a, 25b) when the volume of a portion, communicating with the suction port (29), of the compression chambers (25a, 25b) is increased, and the refrigerant in the refrigerant circuit is compressed and discharged from the discharge port (26) to the discharge chamber (28) when the volume of a portion in which a suction side is closed decreases. The refrigerant in the discharge chamber (28) is supplied from the discharge pipe (15) to the condenser in the refrigerant circuit, and is circulated in the refrigerant circuit. Then, the refrigerant in the discharge chamber (28) is sucked into the scroll compressor (1), again.
Next, the operation of the Oldham ring (50) of this embodiment will be described.
In this embodiment, the first key groove (61) formed in a position adjacent to the back surface of the opposing surface (71) engages with the first key (54) of the Oldham ring (50), allowing the Oldham ring (50) to operate. At that time, the first key (64) protrudes from the ring portion (53) of the Oldham ring (50) toward the housing (23) and further protrudes in the radially inward direction of the ring portion (53). This can sufficiently increase the area of the sliding surface between the first key (54) and the first key groove (61) to reduce a contact pressure of the key sliding surface. Also, the first key (54) protrudes in the radially inward direction of the Oldham ring (50), and the outer periphery of the housing (23) does not have to be notched (see
Also, according to this embodiment, the pair of first keys (54) are opposed to each other by 180° on the Oldham ring (50) to satisfy the relationship such that the interval (A) between the pair of the first keys (54) is smaller than the outer diameter (B) of the facing portion (71) of the housing (23) and the thickness (C) of the ring portion (53) is larger than the thickness (D) of the facing portion (71) of the housing (23). Thus, as illustrated in
Also, the back surface of the facing portion (71) is the tilted surface (71a), and thus, when the Oldham ring (50) is attached to the housing (23), the first key (54) can be easily inserted into the first key groove (61). In this embodiment, the first key (54) engages with the first key groove (61) opened on the back surface of the flange (23a) of the housing (23), allowing the Oldham ring (50) to operate.
According to this embodiment, the first key (64) protrudes from the ring portion (53) of the Oldham ring (50) toward the housing (23) and further protrudes in the radially inward direction of the ring portion (53). This can sufficiently increase the area of the sliding surface between the first key (54) and the first key groove (61) to reduce a contact pressure of the key sliding surface. Therefore, this can contribute to preventing insufficient strength of the first key (54) of the Oldham ring (50).
Also, since the first key (54) protrudes in the radially inward direction of the Oldham ring (50), the outer periphery of the housing (23) does not have to be notched, and the moment of the first key (54) can be reduced. Therefore, this can contribute to preventing the strength of the Oldham ring (50) from decreasing too much.
Further, the first key groove (61) is formed in the position adjacent to the back side of the orbiting scroll facing surface (70) (in the position adjacent to the back surface of the facing portion (71)), and thus, the first key groove (61) does not hinder the formation of the sealing ring (not illustrated). Therefore, this makes it possible to use the seal ring (50) in a configuration in which the first key (54) and the first key groove (61) engage with each other.
Also, according to this embodiment, the interval (A) between the pair of the first keys (54) is smaller than the outer diameter (B) of the facing portion (71) of the housing (23), and the thickness (C) of the ring portion (53) is larger than the thickness (D) of the facing portion (71) of the housing (23). Thus, as illustrated in
Also, according to this embodiment, the back surface of the facing portion (71) is the tilted surface (71a), and thus, when the Oldham ring (50) is attached to the housing (23), the first key (54) can be easily inserted into the first key groove (61), improving ease of attachment.
Also, the first key groove (61) according to this embodiment, which is a groove opened on the back surface of the main body (flange) (23a) of the housing (23), can be easily formed.
As illustrated in
As illustrated in
As illustrated in
Also in such a configuration, the groove opened on the outer peripheral surface of the main body (flange) (23a) of the housing (23) which functions as first key groove (61) can be easily formed.
The above-described embodiment may be modified as follows.
For example, in this embodiment, the interval (A) between the pair of the first keys (54) is set to be smaller than the outer diameter (B) of the facing portion (71) of the housing (23), and the thickness (C) of the ring portion (53) is set to be larger than the thickness (D) of the facing portion(71) of the housing (23). However, these elements do not necessarily have to be set as described above.
In the third variation of the embodiment, oil may remain in the first key groove (61) to prevent the first key (54) from moving smoothly. It is therefore suitable that the housing (23) is provided with an oil removing hole for removing oil from the first key groove (61),
According to this embodiment, the orbiting scroll facing surface (70) of the facing portion (71) of the housing (23) is in contact with and faces the orbiting end plate (22a) of the orbiting scroll (22) to slide on the orbiting end plate (22a). However, as illustrated in
Note that the foregoing description of the embodiments is a merely preferred example in nature, and is not intended to limit the scope, application, or uses of the present disclosure.
As can be seen from the foregoing description, the present disclosure is useful for, in a scroll compressor provided with a compression mechanism having a fixed scroll and an orbiting scroll, a structure of allowing the compression mechanism to hold an Oldham ring that is a mechanism preventing the orbiting scroll from rotating on its axis.
1 Scroll Compressor
21 Fixed Scroll
22 Orbiting Scroll
23 Housing
23
a Flange (Body)
40 Drive Shaft
50 Oldham Ring
51 First Key Mechanism
52 Second Key Mechanism
53 Ring Portion
54 First Key
61 First Key Groove
70 Orbiting Scroll Facing Surface
71 Facing Portion
71
a Tilted Surface
72 Annular Opening
Number | Date | Country | Kind |
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2015-256983 | Dec 2015 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2016/083242 | 11/9/2016 | WO | 00 |