JP2012052417A - Scroll type compressor, and bearing assembling method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll type compressor in which uneven wear of metal supporting the rotation of a main shaft and an orbiting scroll is effectively prevented, and to provide a bearing assembling method.SOLUTION: Bearing metals 18, 24 have grooves 70, 75 formed on the outer circumferential sides thereof respectively, thereby rotatably supporting the main shaft 12 and the orbiting scroll 20. In the bearing metals 18, 24, an end 18a on the side close to a fore end of the main shaft 12, of the bearing metal 18 and an end 24a on the main shaft 12 side in the orbiting scroll 20, of the bearing metal 24 are deflected in the radius-expanding direction and form a so-called crowning shape. Consequently, when gas is compressed in a compression chamber 50 between the orbiting scroll 20 and a fixed scroll 30, and even if the repulsive force caused by the gas to be compressed is applied to the main shaft 12 in the direction orthogonal to its center axis, the bearing metals 18, 24 are elastically deformed in the crowning shape corresponding to their load distribution, so that the bearing metals 18, 24 are hardly unevenly worn.

Description

  The present invention relates to a scroll compressor used in an air conditioner or the like, and a bearing assembling method.

  A scroll compressor used for an air conditioner or the like includes a fixed scroll and a turning scroll. Each of the fixed scroll and the orbiting scroll is formed by integrally forming a spiral wrap wall on one surface side of a disk-shaped end plate. The fixed scroll and the orbiting scroll are made to face each other with the lap wall meshed, and the orbiting scroll is caused to make a revolving orbit with respect to the fixed scroll. And the compression chamber formed between both lap walls is compressed from the compression chamber by moving the compression chamber from the outer peripheral side to the inner peripheral side and reducing its volume (see, for example, Patent Document 1). .

The orbiting scroll is orbitally driven by a main shaft provided integrally with the rotor of the motor. A boss protrudes from one end of the main shaft at a position eccentric from the central axis of the main shaft.
The orbiting scroll is formed with a recess for accommodating the boss of the main shaft. Since the boss is inserted into the recess through the bearing, the orbiting scroll is rotatably held by the boss.
Accordingly, when the main shaft is rotated by the motor, the boss turns along an arc having a radius of an eccentric dimension with respect to the central axis of the main shaft. Then, the orbiting scroll performs rotation (revolution) with a radius that is eccentric with respect to the center of the main shaft.

JP 2000-18182 A

However, in the scroll compressor, there is a problem in that the metal (drive ash) provided between the main shaft and the bearing that rotatably supports the main shaft, and between the boss and the concave portion of the orbiting scroll, is unevenly worn. .
As described above, the orbiting scroll is orbitally driven by the boss provided at one end of the main shaft. The orbiting scroll meshes with the fixed scroll on the side opposite to the side connected to the main shaft, and compresses gas in the space between the orbiting scroll and the fixed scroll while turning. At this time, a load in a direction perpendicular to the central axis of the main shaft acts on one end of the main shaft due to a repulsive force (hereinafter referred to as a gas force) due to the compressed gas. In the metal between the main shaft and the bearing that rotatably supports the main shaft, this load acts more toward the one end side of the main shaft. In the metal between the boss and the concave portion of the orbiting scroll, the load acts more toward the other end side of the main shaft. As described above, the distribution of the load acting in the axial direction of the main shaft is different in each metal, so that the metal is unevenly worn.

  In preparation for such uneven wear, a so-called crowning shape in which the diameter of the sliding surface of the metal is changed in the central axis direction can be considered. However, a film is formed on the metal by surface treatment to improve wear resistance and reduce frictional resistance. If the metal is made into a crowning shape, the film may be thinned by the processing, and the function and durability of the film may be reduced, and this is not a perfect countermeasure against uneven wear.

  The present invention has been made based on such a technical problem, and provides a scroll compressor capable of effectively preventing uneven wear of the main shaft and the metal supporting the rotation of the orbiting scroll, and a method for assembling the bearing. For the purpose.

For this purpose, the present invention provides a housing that forms the outer shell of a scroll compressor, and a main shaft that is rotatably supported in the housing and is integrally formed with an eccentric shaft portion that is offset from the central axis at one end thereof. An orbiting scroll rotatably connected to the eccentric shaft portion of the main shaft, a compression scroll that compresses the refrigerant by facing the orbiting scroll, and a fixed scroll fixed to the housing side. The first bearing provided in the housing is rotatably supported via a cylindrical first bearing metal, and the orbiting scroll is open to the cylindrical second bearing that opens on the side facing the main shaft. The eccentric shaft portion is inserted through the cylindrical second bearing metal so as to be rotatably supported, and the outer peripheral side of the first bearing metal on the side facing the orbiting scroll in the first bearing, and the second Bearing odor At least one of the second outer peripheral side of bearing metal on the side facing the main shaft, characterized in that is provided with a recess.
Thus, when a recessed part is formed, a 1st bearing metal and a 2nd bearing metal will elastically deform in the part corresponding to a recessed part. As a result, the first bearing has a configuration in which the inner diameter of the first bearing metal gradually increases as it approaches the orbiting scroll at the portion corresponding to the recess. Further, the second bearing has a configuration in which the inner diameter of the second bearing metal is a portion corresponding to the concave portion and gradually increases as it approaches the main shaft. In this way, the first bearing metal and the second bearing metal have a so-called crowning shape.
In addition, a recessed part may be formed in both the outer peripheral side of a 1st bearing metal, and the outer peripheral side of a 2nd bearing metal, respectively, and may be formed only in any one.

  The recess can be formed to be continuous with at least part of the circumferential direction on the outer peripheral side of the first bearing metal and the second bearing metal. That is, the arc-shaped recess is formed only in a part of the circumferential direction on the outer peripheral side of the first bearing metal or the second bearing metal, or the circular recess (so-called hole) is formed in the first bearing metal, A plurality of bearing metal can be formed at intervals in the circumferential direction on the outer peripheral side of the second bearing metal, and an annular concave portion is made continuous with the entire circumferential direction on the outer peripheral side of the first bearing metal and the second bearing metal. It can also be formed.

  When the gas is compressed while the orbiting scroll and the fixed scroll are orbiting, the repulsive force due to the compressed gas becomes stronger and weaker in the circumferential direction, and the intensity distribution is generated. As a result, the loads acting on the first bearing metal and the second bearing metal also have different strengths in the circumferential direction. Therefore, at least one of the position, the depth, and the width from the center of the first bearing metal and the second bearing metal on the outer peripheral side of the first bearing metal and the second bearing metal in the circumferential direction. By making the difference in the above, it is possible to vary the amount of elastic deformation in the portions corresponding to the concave portions of the first bearing metal and the second bearing metal and to respond to the load distribution.

The depth of the recess can be smaller than the length along the axial direction of the main shaft of the first bearing metal or the second bearing metal.
Further, at least one of a cylindrical first rising wall formed between the recess and the first bearing metal and a cylindrical second rising wall formed between the recess and the second bearing metal Moreover, it can also be set as the cross-sectional shape from which the thickness becomes small gradually toward the front-end | tip part side of a standing wall from the bottom side of a recessed part.
Further, the recess is formed along the outer peripheral surface of at least one of the first bearing metal and the second bearing metal, so that a part of the outer peripheral surface of the first bearing metal and the second bearing metal is exposed. It can also be set as the structure.
The thickness of the second bearing can be gradually reduced as it goes to the side facing the main shaft.

  The present invention also relates to a method for assembling a bearing having a rotating body housing space having a circular cross section for housing a rotating body, the step of inserting a cylindrical bearing metal into the rotating body housing space, and an inner periphery of the bearing metal. A method for assembling a bearing characterized by comprising a step of finishing the surface to a predetermined inner diameter dimension and a step of forming a recess in the outer peripheral portion of the rotating body housing space of the bearing.

  According to the present invention, by forming the concave portion, the first bearing metal and the second bearing metal are elastically deformed at a portion corresponding to the concave portion, so that a so-called crowning shape is obtained. Thereby, when gas is compressed in the compression chamber between the orbiting scroll and the fixed scroll, even if the load due to the repulsive force of the compressed gas acts as a load in a direction perpendicular to the central axis with respect to the main shaft. The bearing metal is less likely to be unevenly worn. Further, the first and second bearing metals themselves are not subjected to a process for making them into a crowning shape, and if a recess is formed, the crowning shape is naturally formed, so that it does not take time and effort. Furthermore, even when the first and second bearing metals are subjected to a surface treatment for reducing the friction coefficient, the film thickness is not partially reduced by processing, and durability can be improved.

It is sectional drawing which shows the structure of the scroll type compressor in this Embodiment. It is an expanded sectional view which shows the principal part of FIG. (A) is sectional drawing which shows the groove | channel formed in the bearing, (b) is sectional drawing which shows the groove | channel formed in the cylindrical wall of a turning scroll. It is sectional drawing which shows the modification of the shape of a groove | channel. It is sectional drawing which shows the example which replaced with the groove | channel and formed the recessed part. It is sectional drawing which shows the example which changed the shape of the cylindrical wall. It is a figure which shows that the load which acts with the compression force of gas changes according to the turning angle of a turning scroll. It is sectional drawing which shows the application example which made the groove | channel eccentric. It is sectional drawing which shows the application example which varied the depth of the groove | channel in the circumferential direction. It is sectional drawing which shows the application example which provided the groove | channel only in a part of the circumferential direction. It is sectional drawing which shows the application example which varied the width | variety and the depth by filling a groove | channel with a filler. It is sectional drawing which shows the application example which replaced with the groove | channel and formed the hole.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
FIG. 1 is a cross-sectional view for explaining the configuration of the compressor in the present embodiment.
As shown in FIG. 1, the compressor 10 is a vertical scroll type, and is fixed in a housing 11 to a main shaft 12, a revolving scroll 20 that revolves together with the main shaft 12, and a bearing 14. And a fixed scroll 30 fixed to.
In such a compressor 10, the refrigerant is introduced into the housing 11 from the refrigerant introduction port P <b> 1 formed on one end side of the housing 11, and in the compression chamber 50 formed between the orbiting scroll 20 and the fixed scroll 30. The refrigerant is compressed. The compressed refrigerant is discharged from a refrigerant discharge port P <b> 2 formed on the other end side of the housing 11.

In the orbiting scroll 20, a wrap wall 22 having a predetermined height is formed integrally with a disc-shaped end plate 21.
On the other hand, in the fixed scroll 30, a spiral wrap wall 32 is formed on the end plate 31 that faces the orbiting scroll 20 and meshes with the wrap wall 22 of the orbiting scroll 20.

In this way, the orbiting scroll 20 and the fixed scroll 30 combine the wrap wall 22 and the wrap wall 32 with each other. Thereby, a compression chamber 50 is formed between the orbiting scroll 20 and the fixed scroll 30.
The refrigerant introduced into the compression chamber 50 from the outer peripheral side of the orbiting scroll 20 and the fixed scroll 30 is sequentially sent from the outer peripheral side to the inner peripheral side and compressed by the revolution of the orbiting scroll 20 with respect to the fixed scroll 30. The refrigerant compressed in the compression chamber 50 is discharged from a refrigerant discharge port P2 formed on the other end side of the housing 11 through a discharge hole 37 formed in the fixed scroll 30 and a reed valve 38 provided in the discharge hole 37. Is done.

  Both ends of the main shaft 12 are rotatably supported by the housing 11 via a bearing 13 and a bearing (first bearing, rotating body accommodation space) 14. The main shaft 12 is rotationally driven by a motor 17 including a stator 15 fixed to the inner surface of the housing 11 and a rotor 16 fixed to the outer peripheral surface of the main shaft 12 and facing the stator 15. The main shaft 12 is driven to rotate by one end of the main shaft 12 projecting outside through the housing 11 and connected to one end of the main shaft 12 by a driving source (not shown) such as an engine or a motor provided outside. You can also

  Here, in order to reduce friction between these sliding surfaces between the one end of the main shaft 12 and the bearing 13 and between the other end of the main shaft 12 and the bearing 14, respectively, a cylindrical bearing metal (first One bearing metal) 18 is provided.

As shown in FIG. 2, a boss 19 is formed in a cylindrical shape at the other end of the main shaft 12 at a position eccentric from the central axis of the main shaft 12 by a predetermined dimension. A cylindrical tubular wall (second bearing, rotating body housing space) 23 is formed on the main shaft 12 side of the orbiting scroll 20, and the boss 19 is housed in a recess 23 a formed inside the tubular wall 23. ing. The boss 19 is inserted into the recess 23 a via a cylindrical bearing metal (second bearing metal) 24, so that the orbiting scroll 20 is rotatably held by the boss 19. Thereby, the orbiting scroll 20 is provided eccentrically by a predetermined dimension with respect to the center of the main shaft 12, and when the main shaft 12 rotates around its axis, the orbiting scroll 20 is eccentric with respect to the center of the main shaft 12. Performs rotation (revolution) with the dimensions as the radius. An Oldham ring (not shown) is interposed between the orbiting scroll 20 and the main shaft 12 so that the orbiting scroll 20 does not rotate while revolving.
The main shaft 12 has a lubricating oil passage 12a for supplying the lubricating oil sucked up from the oil reservoir at the bottom of the housing 11 from the upper end of the main shaft 12 to the bearing metal 24 between the main shaft 12 and the recess 23a. Has been.

  Here, in the bearing 14, an annular continuous groove 70 is formed on the outer peripheral side of the bearing metal 18 that supports the main shaft 12 so as to face the side facing the orbiting scroll 20. The groove 70 has an inner diameter that is a certain dimension larger than the inner diameter of the hole 14 a for inserting the bearing metal 18 formed in the bearing 14, so that the gap 70 is interposed between the bearing metal 18 and the groove 70. A cylindrical rising wall 71 is formed.

Further, an annular continuous groove 75 is formed at the tip of the cylindrical wall 23 formed on the main shaft 12 side of the orbiting scroll 20 so as to face the side facing the bearing 14. The groove 75 is formed with a diameter larger than the inner diameter of the cylindrical wall 23 and smaller than the outer diameter of the cylindrical wall 23.
Thereby, a cylindrical rising wall portion 76 is formed between the bearing metal 24 and the groove 75.

  In such a compressor 10, the bearing metals 18 and 24 are press-fitted into the hole 14 a and the cylindrical wall 23 of the bearing 14 at the time of production. Then, the inner peripheral surfaces of the bearing metals 18 and 24 are finished to a predetermined inner diameter. Thereafter, the grooves 70 and 75 are cut on the outer peripheral sides of the bearing metals 18 and 24.

Then, as shown in FIGS. 3A and 3B, in such a compressor 10, the hole 14 a and the hole 14 a are press-fitted into the hole 14 a of the bearing 14 and the bearing metal 18 and 24 press-fitted into the cylindrical wall 23. A force is generated on the inner peripheral surface of the cylindrical wall 23 to press the hole 14a and the cylindrical wall 23 toward the outer peripheral side (radial direction) in a direction orthogonal to the axis of the main shaft 12. Then, in the portion where the grooves 70 and 75 are formed, the rising wall portions 71 and 76 are centered on the base end portions 71 a and 76 a on the bottom side of the grooves 70 and 75, and the distal end portions 71 b and 76 b side is the outer periphery of the main shaft 12. Elastically deforms like a cantilever beam toward the side. Accordingly, the end portions 18a and 24a on the side corresponding to the rising wall portions 71 and 76 also bend in the direction in which the diameters of the cylindrical bearing metals 18 and 24 increase.
At this time, it is preferable to perform R machining or chamfering C machining on the corner X of the joining portion between the bottom of the grooves 70 and 75 and the base end parts 71a and 76a of the rising wall parts 71 and 76 in order to avoid stress concentration. .

In this way, the grooves 70 and 75 are formed on the outer peripheral sides of the bearing metals 18 and 24, so that the bearing metals 18 and 24 that rotatably support the main shaft 12 and the orbiting scroll 20 are close to the tips of the main shaft 12. The end portion 18a on the side and the end portion 24a on the main shaft 12 side in the orbiting scroll 20 bend in the direction in which the diameter increases, forming a so-called crowning shape.
Thereby, when gas is compressed in the compression chamber 50 between the orbiting scroll 20 and the fixed scroll 30, the repulsive force (hereinafter referred to as gas force) due to the compressed gas is perpendicular to the main shaft 12 and the central axis of the main shaft 12. Even if a load in the direction is applied, the bearing metals 18 and 24 are elastically deformed to have a crowning shape corresponding to the load distribution, so that the bearing metals 18 and 24 are less likely to be unevenly worn.
Further, the bearing metals 18 and 24 themselves are not subjected to the processing for making them into a crowning shape, and if they are press-fitted, they naturally become crowning shapes, so that it does not take time and effort.
Further, even when the bearing metals 18 and 24 are subjected to a surface treatment for reducing the friction coefficient, the film thickness is not partially reduced by processing, and the durability can be enhanced.

<Other embodiments>
In addition to the grooves 70 and 75 shown in the above embodiment, the following configurations can be adopted.
For example, as shown in FIG. 4, in the bearing 14 and the cylindrical wall 23 on the outer peripheral side of the bearing metal 18, 24, annular grooves 72, 77 are directed from the bottom portions 72a, 77a toward the open ends 72b, 77b. Thus, the groove width may be a tapered cross section that gradually expands toward the inner peripheral side (bearing metal 18, 24 side).

In such a configuration, the rising wall portions 73 and 78 formed between the bearing metals 18 and 24 and the grooves 72 and 77 go from the proximal end portions 73a and 78a to the distal end portions 73b and 78b so that the thickness thereof increases. Gradually decreases. Since the load applied when the orbiting scroll 20 is turned increases and the tip end portions 73b and 78b on which the bearing metals 18 and 24 are more strongly hit are thinner, the rising wall portions 73 and 78 and the bearing metals 18 and 24 are elastically deformed. The amount increases. Thereby, wear of bearing metals 18 and 24 can be controlled more effectively.
Further, since the rising wall portions 73 and 78 have a large thickness on the base end portions 73a and 78a side, the stress acting on the base end portions 73a and 78a at the bottom of the grooves 72 and 77 is reduced, and the rising wall portions 73 and 78, A strength of 78 can be ensured.

Moreover, it can also be set as a structure as shown in FIG. In the configuration shown in FIG. 5, the outer circumferential surfaces 18 b and 24 b of the end portions 18 a and 24 a of the bearing metals 18 and 24 are exposed to the bearing 14 and the cylindrical wall 23 on the outer circumferential side of the bearing metals 18 and 24. The recess 80 may be formed. Thereby, since the bearing metals 18 and 24 do not support the outer peripheral surfaces 18b and 24b at the end portions 18a and 24a, the amount of elastic deformation becomes larger. 3 and FIG. 4, the end portions 18a and 24a of the bearing metals 18 and 24 can be locally crowned to suppress the wear of the bearing metals 18 and 24. can do.
In the configuration shown in FIG. 5, grooves 70, 72, 75, and 77 as shown in FIGS. 3 and 4 can be formed at the bottom of the recess 80.

Furthermore, a configuration as shown in FIG.
That is, in the configuration shown in FIG. 6, the thickness of the cylindrical wall 23 ′ formed on the main shaft 12 side of the orbiting scroll 20 and into which the bearing metal 24 is press-fitted gradually decreases toward the tip end portion 23 b. Forming.
In such a configuration, the cylindrical wall 23 ′ is more easily elastically deformed toward the distal end portion 23 b side, and the bearing metal 24 can also be locally crowned at the end portion 24 a. Wear can be suppressed.

  Moreover, in the said embodiment, although it was set as the structure which forms the groove | channels 70, 72, 75, 77 only in part with respect to the height of the bearing metals 18 and 24, the depth is not limited at all. .

  Here, as shown in FIG. 7, the repulsive force generated by compressing the gas during the turning of the orbiting scroll 20 varies depending on the angle in the circumferential direction. Thus, the load acting on the first bearing metal (vector arrow in the figure) also has different strengths in the circumferential direction.

  Therefore, as shown in FIG. 8A, an annular groove 90 may be provided in the bearing 14 and the cylindrical wall 23 on the outer peripheral side of the bearing metals 18 and 24 so as to be eccentric from the center thereof. Thereby, the radii r1 and r2 from the center of the bearing metal 18 and 24 differ according to the position of the circumferential direction. Here, the groove 90 increases the radius r1 at the position (angle) at which a large load acts according to the strength distribution in the circumferential direction of the load acting when the orbiting scroll 20 is turned, and the thickness of the rising wall portions 71 and 76 is increased. Increase the size. On the other hand, at a position (angle) at which the applied load is small, the radius r2 is reduced and the thickness of the rising wall portions 71 and 76 is reduced. In this way, by decentering the groove 90, the rising wall portions 71 and 76 can be made to correspond to the distribution of the load generated when the orbiting scroll 20 is turned.

As shown in FIG. 8B, an annular groove 91 is formed in the bearing 14 and the cylindrical wall 23 on the outer peripheral side of the bearing metals 18 and 24, and an eccentric sub groove 92 is formed at the bottom of the groove 91. Can be formed. In this case, the sub-groove 92 increases the radius r1 at the position (angle) at which a large load acts according to the strength distribution in the circumferential direction of the load that acts when the orbiting scroll 20 orbits. Increase the thickness. On the other hand, at a position (angle) at which the applied load is small, the radius r2 is reduced and the thickness of the rising wall portions 71 and 76 is reduced.
In such a case, since the base portions 71 and 76 of the rising wall portions 71 and 76 are thickened at a position where a large load is applied, it is possible to reliably resist the stress acting on the portions.

Moreover, as shown to Fig.9 (a), the groove | channel 93 which continues in an annular | circular shape can also vary the depth by the position in the circumferential direction. In this case, the depth d1 is increased at the position (angle) at which a large load is applied according to the intensity distribution in the circumferential direction of the load that is applied when the orbiting scroll 20 is turned, and the elastic deformation easily occurs. At a position where the load is small, the depth d2 is reduced.
Here, the depth of the groove 93 can be changed continuously, or the depth can be varied stepwise in the circumferential direction.

Furthermore, as shown in FIG. 9B, sub-grooves 95 having different depths depending on positions in the circumferential direction can be formed on the bottom surface of the annular groove 94 having a constant depth. In this case, the depth of the sub-groove 95 can be zero in a part of the circumferential direction.
In the example shown in FIG. 9C, a sub groove 95 is formed at the bottom of the grooves 72 and 77 similar to those shown in FIG.

In the example shown in FIGS. 10A and 10B, the groove 96 can be formed only in a part in the circumferential direction. In this case, it is preferable to form so as to include a position where the largest load is applied according to the intensity distribution in the circumferential direction of the load that is applied when the turning scroll 20 is turned.
As shown in FIG. 10C, the groove 97 may be formed obliquely with respect to the groove 96 shown in FIG.

  Further, as shown in FIGS. 11A and 11B, a part of the groove 98 having a constant depth is filled with the fillers 99A and 99B, so that the width and the groove depth are substantially increased in the circumferential direction. It is possible to form grooves 98A and 98B having different distributions.

  As shown in FIG. 11, instead of the grooves, for example, a large number of circular holes 100 may be formed at intervals in the circumferential direction. At this time, as shown in FIG. 11A, the hole 100 may be formed only in a part of the circumferential direction. Moreover, as shown in FIG.11 (b), the pitch in the circumferential direction of the hole 100 can also be made into an unequal space | interval. In that case, the pitch of the holes 100 is narrowed at the position where the largest load is applied according to the strength distribution in the circumferential direction of the load that is applied when the orbiting scroll 20 is turned. As shown in FIG. 11 (c), the holes 100 may have different diameters in the circumferential direction.

Needless to say, the above-described configurations can be appropriately combined and employed.
In addition to this, as long as it does not depart from the gist of the present invention, the configuration described in the above embodiment can be selected or changed to another configuration as appropriate.

  DESCRIPTION OF SYMBOLS 10 ... Compressor, 11 ... Housing, 12 ... Main shaft, 13 ... Bearing, 14 ... Bearing (first bearing, rotor housing space), 15 ... Stator, 16 ... Rotor, 17 ... Motor, 18 ... Bearing metal (First bearing metal), 18a ... end, 19 ... boss, 20 ... orbiting scroll, 22 ... wrap wall, 23 ... cylindrical wall (second bearing, rotating body housing space), 23a ... concave part, 24 ... Bearing metal (second bearing metal), 24a ... end, 30 ... fixed scroll, 32 ... wrap wall, 50 ... compression chamber, 70, 72, 75 ... groove, 71, 73, 76 ... rising wall, 80 ... Recess

Claims (10)

A housing forming an outer shell of the scroll compressor;
A main shaft that is rotatably supported in the housing and is integrally formed with an eccentric shaft portion offset from the central axis at one end thereof;
A orbiting scroll rotatably connected to the eccentric shaft portion of the main shaft;
Forming a compression chamber for compressing the refrigerant by facing the orbiting scroll, and a fixed scroll fixed to the housing side,
The main shaft is rotatably supported by a first bearing provided in the housing via a cylindrical first bearing metal,
The orbiting scroll is rotatably supported by inserting the eccentric shaft portion through a cylindrical second bearing metal into a cylindrical second bearing opened on the side facing the main shaft,
At least one of the outer peripheral side of the first bearing metal on the side facing the orbiting scroll in the first bearing and the outer peripheral side of the second bearing metal on the side facing the main shaft in the second bearing. A scroll compressor characterized in that a recess is provided.   2. The scroll compressor according to claim 1, wherein an inner diameter of the first bearing metal is gradually increased as it approaches the orbiting scroll at a portion corresponding to the recess.   3. The scroll compressor according to claim 1, wherein an inner diameter of the second bearing metal is gradually enlarged as it approaches the main shaft at a portion corresponding to the concave portion. 4.   The said recessed part is formed so that it may continue in at least one part of the circumferential direction in the outer peripheral side of said 1st bearing metal and said 2nd bearing metal. The scroll compressor according to the item.   The concave portion has at least one of a position, a depth and a width from the center of the first bearing metal and the second bearing metal on the outer peripheral side of the first bearing metal and the second bearing metal. The scroll compressor according to any one of claims 1 to 4, wherein the scroll compressor is different in a circumferential direction.   3. The scroll compressor according to claim 1, wherein a depth of the recess is smaller than a length of the first bearing metal or the second bearing metal along an axial direction of the main shaft. 4. .   A cylindrical first rising wall formed between the first bearing metal and the recess, and a cylindrical second rising wall formed between the second bearing metal and the recess. The at least one of these is made into the cross-sectional shape from which the thickness becomes small gradually toward the front-end | tip part side of the said rising wall from the bottom part side of the said recessed part, It is any one of Claim 1 to 6 characterized by the above-mentioned. Scroll compressor.   The recess is formed along the outer peripheral surface of at least one of the first bearing metal and the second bearing metal, so that one of the outer peripheral surfaces of the first bearing metal and the second bearing metal. The scroll compressor according to any one of claims 1 to 7, wherein a portion is exposed.   The scroll type compression according to any one of claims 1 to 8, wherein the second bearing has a shape in which the wall thickness gradually decreases as it goes to the side facing the main shaft. Machine. A method for assembling a bearing having a rotating body housing space having a circular cross section for housing a rotating body,
Inserting a cylindrical bearing metal into the rotating body housing space;
Finishing the inner peripheral surface of the bearing metal to a predetermined inner diameter;
And a step of forming a recess in an outer peripheral part of the rotating body housing space of the bearing.

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