The present invention relates to a scroll compressor.
Priority is claimed on Japanese Patent Application No. 2017-162570, filed on Aug. 25, 2017, the content of which is incorporated herein by reference.
A scroll compressor has a casing, a motor, and a scroll compression unit. The motor and the scroll compression unit are housed in a space formed inside the casing (for example, refer to Patent Document 1).
Patent Document 1 discloses a scroll compressor including a casing, a thrust bearing, a scroll compression unit including a turning scroll and a fixed scroll, and a motor.
The casing has a cylindrical casing body and a bearing holder that protrudes inward in a radial direction from an inner peripheral surface of the casing body. The bearing holder divides a space formed inside the casing body into a motor housing space and a compression unit housing space in an axial direction.
The bearing holder has a flow path for guiding a lubricant to be supplied into the motor housing space and a fluid to be compressed by the compression unit, from the motor housing space to the compression unit housing space.
The thrust bearing is disposed on the other side surface (surface located on the compression unit housing space side) of the bearing holder in the axial direction. The thrust bearing has a function to receive a thrust-direction force generated when the turning scroll is rotated.
Patent Document 1: Japanese Patent Publication No. 5518169
However, according to the scroll compressor disclosed in Patent Document 1 described above, when the fluid supplied into the motor housing space moves to the compression unit housing space via the thrust bearing, there is a problem in that a considerable pressure loss occurs.
Therefore, the present invention aims to provide a scroll compressor which can properly supply a lubricant and can reduce a pressure loss of a fluid (working fluid) when the fluid passes through a thrust bearing.
According to an aspect of the present invention, in order to solve the above-described problem, there is provided a scroll compressor including: a casing having a casing body in which a housing space having a columnar shape around an axis is formed, and a bearing holder having an annular shape by protruding inward in a radial direction from an inside of the casing body and which is formed so as to divide the housing space into a motor housing space located on one side in an axial direction and a compression unit housing space located on the other side in the axial direction; a rotary shaft that is located to extend in the axial direction in the housing space, and that is rotatable around the axis; a motor that is located in the motor housing space, and having a stator having an annular shape formed around the axis and having an outer peripheral surface fixed to an inner peripheral surface of the casing body, and a rotor located inside the stator and disposed on an outer peripheral surface of the rotary shaft; a scroll compression unit that is located inside the compression unit housing space, and which is configured to compress a fluid flowing from the motor housing space to the compression unit housing space; a first radial bearing that is fixed to an inner peripheral surface of the bearing holder, and rotatably supporting the rotary shaft; and a thrust bearing having an annular shape formed around the axis, that is fixed to a surface of the bearing holder facing the other side in the axial direction, and supporting the scroll compression unit in the axial direction. The outer peripheral surface of the stator has a stator groove portion which extends from one end to the other end of the stator in the axial direction. A plurality of the stator groove portions are located at an interval in a circumferential direction of the stator. In the bearing holder, portions corresponding to formation positions of the plurality of stator groove portions each have a flow path penetrating the bearing holder in the axial direction. In the thrust bearing, a portion facing the flow path has a first recess portion recessed from one side in the axial direction to the other side in the axial direction. An outer peripheral portion of the first recess portion has a first groove portion which extends from a bottom surface of the first recess portion to a surface located on a side opposite to a surface having the first recess portion formed thereon in the axial direction and communicates with the first recess portion.
In the bearing holder, the portion corresponding to the formation position of the plurality of stator groove portions has each flow path penetrating the bearing holder in the axial direction. In this manner, the fluid and the lubricant which pass through the stator groove portion are likely to be guided to the flow path. In this manner, the lubricant can be properly supplied, and a pressure loss of the fluid (working fluid) can be reduced when the fluid passes through the thrust bearing.
In addition, in the thrust bearing, the portion facing the flow path has the first recess portion recessed from one side in the axial direction to the other side in the axial direction. In this manner, the fluid and the lubricant which pass through the flow path can be guided into and retained in the first recess portion.
Furthermore, the outer peripheral portion of the first recess portion has the first groove portion which communicates with the first recess portion by extending from the bottom surface of the first recess portion to the surface located on the side opposite to the surface having the first recess portion formed thereon in the axial direction. In this manner, the pressure loss of the fluid can be reduced when the fluid passes through the thrust bearing.
In addition, the thrust bearing has the first recess portion. In this manner, without increasing a cross section of the flow path of the first groove portion, the pressure loss of the fluid can be reduced when the fluid passes through the thrust bearing.
In addition, in the scroll compressor according to the aspect of the present invention, the thrust bearing may have a second recess portion disposed inside the first recess portion, communicating with the first recess portion, and extending to an inner peripheral surface of the thrust bearing.
The second recess portion configured in this way is provided. Accordingly, the lubricant retained inside the first recess portion can be supplied to the bearing (for example, the first radial bearing) located inside in the radial direction.
In addition, in the scroll compressor according to the aspect of the present invention, a width of the second recess portion in a circumferential direction may be narrower than a width of the first recess portion in the circumferential direction.
For example, if the width of the second recess portion in the circumferential direction is wider than the width of the first recess portion in the circumferential direction, a large amount of the fluid and the lubricant is supplied inward in the radial direction of the thrust bearing. For this reason, the supply amount of the fluid and the lubricant to the scroll compression unit may decrease, thereby causing a possibility that compression efficiency may be degraded in the scroll compression unit.
On the other hand, the width of the second recess portion in the circumferential direction is made narrower than the width of the first recess portion in the circumferential direction. In this manner, the lubricant is supplied inward in the radial direction of the thrust bearing, and moreover, the compression efficiency can be improved in the scroll compression unit.
In addition, the scroll compressor according to the aspect of the present invention may include a thrust plate disposed between the bearing holder and the scroll compression unit in the axial direction. In an outer peripheral portion of the thrust plate, a portion facing the first groove portion may have a second groove portion extending from one surface to the other surface, which is located in the axial direction.
The second groove portion configured in this way is provided. Accordingly, the pressure loss of the fluid can be reduced when the fluid passes through the thrust plate.
In addition, the scroll compressor according to the aspect of the present invention may include an oil separator disposed in the casing. A lower portion of the thrust plate may have a lubricant supply groove portion which guides a lubricant supplied from the oil separator to the thrust bearing. A lower portion of the thrust bearing facing the lubricant supply groove portion may have an inclined groove portion which guides the lubricant to flow inward in the radial direction.
According to this configuration, the lubricant supplied to the lubricant supply groove portion from the oil separator can be supplied to the bearing located inside in the radial direction of the thrust bearing via the inclined groove portion.
In addition, in the scroll compressor according to the aspect of the present invention, the rotary shaft may have an eccentric shaft portion extending to the compression unit housing space. The scroll compressor may further include a fixed scroll fixed to an inner peripheral surface of the casing, a turning scroll located between the fixed scroll and the eccentric shaft portion, extending in the axial direction, and including a boss portion surrounding the eccentric shaft portion, a drive bush disposed on an outer peripheral surface of the eccentric shaft portion, and partially located inside the boss portion, and a second radial bearing disposed between the drive bush and the boss portion.
According to this configuration, the turning scroll can turn when the rotary shaft is rotated. In addition, the lubricant can be supplied to the second radial bearing via the second recess portion or the second recess portion and the inclined groove portion.
According to the present invention, the lubricant can be properly supplied, and the pressure loss of the fluid (working fluid) can be reduced when the fluid passes through the thrust bearing.
Hereinafter, an embodiment to which the present invention is applied will be described in detail with reference to the drawings.
A scroll compressor 10 according to the embodiment of the present invention will be described with reference to
The axis O indicates the axis of the rotary shaft 15 and the axis of a casing 12. The scroll compressor 10 has the casing 12, the rotary shaft 15, radial bearing 17, 19, and 27, a drive bush 22, a motor 24, a scroll compression unit 25, an oil separator (not illustrated), a throttle portion (not illustrated), a thrust bearing 29, a thrust plate 31, and an Oldham ring 33.
Next, the casing 12 will be described with reference to
The casing 12 has a casing body 36, a first lid 37, a second lid 38, and a bearing holder 44.
The casing body 36 includes a first cylindrical portion 41 and a second cylindrical portion 42. The first cylindrical portion 41 is a member having a cylindrical shape formed around the axis O. Both ends of the first cylindrical portion 41 are open ends.
The first cylindrical portion 41 has an inner peripheral surface 41a and a motor housing space 41A. The motor housing space 41A is a columnar space defined by the inner peripheral surface 41a of the first cylindrical portion 41 and the bearing holder 44.
The motor 24 is housed in the motor housing space 41A.
A mist-like lubricant and a fluid (working fluid) to be compressed by the scroll compression unit 25 is supplied to the motor housing space 41A from an outside of the casing 12.
The second cylindrical portion 42 is a member having a cylindrical shape formed around the axis O. Both ends of the second cylindrical portion 42 are open ends.
The second cylindrical portion 42 has an inner peripheral surface 42a and a compression unit housing space 42A. The compression unit housing space 42A is a columnar space defined by the inner peripheral surface 42a of the second cylindrical portion 42 and the bearing holder 44. The scroll compression unit 25 is housed in the compression unit housing space 42A. The compression unit housing space 42A together with the motor housing space 41A configures the housing space 36A.
The bearing holder 44 protrudes inward in a radial direction of the casing 12 from an inner peripheral surface of a boundary portion between the first cylindrical portion 41 and the second cylindrical portion 42. In the bearing holder 44, the housing space 36A is divided into the motor housing space 41A located on one side (one side in an axial direction) in the direction of the axis O and the compression unit housing space 42A located on the other side (other side in the axial direction) in the direction of axis O.
The bearing holder 44 has a first portion 44A including a plurality of flow paths 47, and a second portion 44B.
The first portion 44A extends inward in a circumferential direction from an inner side of the boundary portion between the first cylindrical portion 41 and the second cylindrical portion 42. The first portion 44A is a ring-shaped member.
The first portion 44A has a first surface 44a, a second surface 44b, and the plurality of flow paths 47. The first surface 44a is a surface facing one side (one side in the axial direction) in the direction of the axis O. The second surface 44b is a surface facing the other side (other side in the axial direction) in the direction of the axis O.
The plurality of flow paths 47 are disposed at an interval in the circumferential direction of the first portion 44A. One end of the plurality of flow paths 47 is exposed on the first surface 44a, and the other end is exposed on the second surface 44b. The plurality of flow paths 47 cause the motor housing space 41A and the compression unit housing space 42A to communicate with each other.
The plurality of flow paths 47 may have mutually different widths in the circumferential direction. In this way, the plurality of flow paths 47 are caused to have mutually different widths in the circumferential direction. In this manner, the plurality of flow paths 47 are located to avoid a member located on the second surface 44b side of the bearing holder 44.
Each of the plurality of flow paths 47 configured as described above is disposed at a position corresponding to one of the stator groove portions 57A.
In this way, the flow path 47 penetrating the bearing holder 44 in the direction of the axis O is disposed in the portion corresponding to the formation position of the plurality of stator groove portions 57A in the bearing holder 44. In this manner, the fluid and the lubricant which pass through the stator groove portion 57A are likely to be guided to the flow path 47. In this manner, the pressure loss of the fluid can be reduced when the fluid passes through the flow path 47.
The first lid 37 is disposed in the first cylindrical portion 41 so as to block the open end of the first cylindrical portion 41 on a side having no bearing holder 44.
The first lid 37 has a boss portion 37A extending into the motor housing space 41A. The first lid 37 is fixed to the first cylindrical portion 41 by a bolt, for example.
The second lid 38 is disposed in the second cylindrical portion 42 so as to block the open end of the second cylindrical portion 42 on a side having no bearing holder 44. The second lid 38 is fixed to the second cylindrical portion 42 by a bolt, for example.
The rotary shaft 15 is housed inside the casing 12 in a state where the rotary shaft 15 extends in the X-direction. The rotary shaft 15 has a rotary shaft body 52 and an eccentric shaft portion 54. The rotary shaft body 52 has one end portion 52A located on the first lid 37 side and the other end portion 52B located on the second lid 38 side.
The one end portion 52A has a columnar shape. The one end portion 52A has a smaller diameter than a portion excluding the one end portion 52A and the other end portion 52B in the rotary shaft body 52. The one end portion 52A is rotatably supported by the radial bearing 17 disposed on the inner peripheral surface of the boss portion 37A.
The other end portion 52B has a columnar shape. The other end portion 52B has a smaller diameter than the portion excluding the one end portion 52A and the other end portion 52B. The other end portion 52B is rotatably supported by a radial bearing 19 (first radial bearing) disposed on an inner peripheral surface 44c of the bearing holder 44.
The eccentric shaft portion 54 is disposed on a side facing the scroll compression unit 25 in the other end portion 52B. The eccentric shaft portion 54 is disposed at a position shifted from the axis O. The eccentric shaft portion 54 extends in the X-direction. The eccentric shaft portion 54 is housed inside the drive bush 22 having a cylindrical shape.
The rotary shaft 15 configured as described above is rotated around the axis O by the motor 24.
The motor 24 has a rotor 56 and a stator 57. The rotor 56 is fixed to an outer peripheral surface of the rotary shaft body 52 located between the one end portion 52A and the other end portion 52B.
Next, the stator 57 will be described with reference to
The stator 57 has a plurality of stator groove portions 57A. The plurality of stator groove portions 57A extend from one end 57B to the other end 57C of the stator 57 in the direction of the axis O.
The plurality of stator groove portions 57A are located at an interval in the circumferential direction of the stator 57.
Referring to
The scroll compression unit 25 is located in the compression unit housing space 42A inside the casing 12. The scroll compression unit 25 has a turning scroll 61 and a fixed scroll 63.
The turning scroll 61 and the fixed scroll 63 are located to face each other in the X-direction.
The turning scroll 61 has an end plate portion 61A, a boss portion 61B, and a spiral portion 61C. The end plate portion 61A faces the end plate portion 63A of the fixed scroll 63 in the X-direction.
The boss portion 61B is disposed on a surface of the end plate portion 61A on a side facing the rotary shaft 15. The boss portion 61B has a cylindrical shape.
The spiral portion 61C is disposed on a surface of the end plate portion 61A on a side facing the fixed scroll 63. The spiral portion 61C extends in a direction toward the fixed scroll 63.
The fixed scroll 63 is fixed to the inside (inner peripheral surface 42a) of the casing 12. The fixed scroll 63 has an end plate portion 63A, a spiral portion 63B, and a discharge hole 63C.
The spiral portion 63B is disposed on a surface of the end plate portion 63A on a side facing the turning scroll 61. The spiral portion 63B meshes with the spiral portion 61C. A space 65 for compressing the fluid is formed between the turning scroll 61 and the fixed scroll 63.
The discharge hole 63C is formed to penetrate a central portion of the end plate portion 63A.
The scroll compression unit 25 configured as described above compresses the fluid flowing into the compression unit housing space 42A from the motor housing space 41A, and discharges the compressed fluid from the discharge hole 63C.
A radial bearing 27 (second radial bearing) is disposed between the drive bush 22 and the boss portion 61B.
An oil separator (not illustrated) is installed in the second lid 38 in a state where the lubricant can be supplied to a bottom portion of the compression unit housing space 42A. The oil separator supplies the lubricant to the lubricant supply groove portion 31A of the thrust plate 31 via a throttle portion (not illustrated) installed in a lower portion of the fixed scroll 63.
Next, the thrust bearing 29 will be described with reference to
The thrust bearing 29 has a bearing body 71, a first recess portion 72, a first groove portion 74, a second recess portion 76, a plurality of screw holes 78 and 79, an Oldham keyway 81, and an inclined groove portion 83.
The bearing body 71 is an annular member having an annular shape formed around the axis O. The bearing body 71 is located between the bearing holder 44 and the thrust plate 31 in the direction of the axis O. The bearing body 71 has first and second surfaces 71a and 71b perpendicular to the X-direction.
The first surface 71a is in contact with the second surface 44b of the bearing holder 44. The second surface 71b is a surface located on a side opposite to the first surface 71a. The second surface 71b is in contact with the thrust plate 31.
The first recess portion 72 is disposed in each portion facing each flow path 47 in the bearing body 71. The first recess portion 72 has a bottom surface 72a. The first recess portion 72 is recessed from one side in the direction of the axis O to the other side in the direction of the axis O (in other words, from the first surface 71a to the second surface 71b side).
In this way, the first recess portion 72 disposed at the position facing each flow path 47 is provided. Accordingly, the fluid and the lubricant which pass through the stator groove portion 57A and the flow path 47 can be retained inside the first recess portion 72.
As an example,
The plurality of first groove portions 74 are disposed in the outer peripheral portion of the first recess portion 72. The first groove portion 74 faces a portion of the flow path 47 in the direction of the axis O (refer to
The first groove portion 74 extends from the bottom surface 72a of the first recess portion 72 to the second surface 71b in the direction of the axis O. The first groove portion 74 communicates with the first recess portion 72. The first groove portion 74 causes the first recess portion 72 and the compression unit housing space 42A located on the second surface 71b side to communicate with each other.
In this way, the bearing body 71 facing the flow path 47 has the first recess portion 72 recessed from the one side in the direction of the axis O to the other side in the direction of the axis O. The outer peripheral portion of the first recess portion 72 has the first groove portion 74 which causes the first recess portion 72 and the compression unit housing space 42A located on the second surface 71b side to communicate with each other. In this manner, the lubricant can be properly supplied, and the pressure loss of the fluid can be reduced when the fluid passes through the thrust bearing 29.
In addition, the thrust bearing 29 has the first recess portion 72. In this manner, without increasing a cross section of the flow path of the first groove portion 74, the pressure loss of the fluid can be reduced when the fluid passes through the thrust bearing 29.
The second recess portion 76 is disposed inside each of the three first recess portions 72 which are wide in the circumferential direction in the bearing body 71. The second recess portion 76 communicates with the first recess portion 72, and extends to the inner peripheral surface 71c (inner peripheral surface of the thrust bearing 29) of the bearing body 71. In this manner, the second recess portion 76 causes the first recess portion 72 and the compression unit housing space 42A located inside the inner peripheral surface 71c to communicate with each other in the radial direction.
For example, as illustrated in
The second recess portion 76 configured in this way is provided. Accordingly, the lubricant retained inside the first recess portion 72 can be supplied to the radial bearings 19 and 27 located inside in the radial direction.
For example, it is preferable that the width W2 of the second recess portion 76 in the circumferential direction is narrower than the width W1 of the first recess portion 72 in the circumferential direction.
For example, if the width W2 of the second recess portion 76 in the circumferential direction is wider than the width W1 of the first recess portion 72 in the circumferential direction, a large amount of the fluid and the lubricant is supplied inward in the radial direction of the thrust bearing 29. Therefore, there is a possibility that the compression efficiency may be degraded in the scroll compression unit 25 due to a decrease in the amount of the fluid and the lubricant which are supplied to the scroll compression unit 25 side.
On the other hand, the width W2 of the second recess portion 76 in the circumferential direction is made narrower than the width W1 of the first recess portion 72 in the circumferential direction. In this manner, the lubricant is supplied inward in the radial direction of the thrust bearing 29, and moreover, the compression efficiency can be improved in the scroll compression unit 25.
The plurality of screw holes 78 and 79 are disposed in the bearing body 71 in the circumferential direction. The plural of screw holes 78 and 79 are holes for locating a screw or a bolt to be connected to a member located in the direction of the axis O.
The number and an arrangement of the plurality of screw holes 78 and 79 illustrated in
The Oldham keyway 81 is formed on the second surface 71b side of the bearing body 71. The Oldham keyway 81 is a groove used when the Oldham ring 33 is mounted on the thrust bearing 29.
The inclined groove portion 83 is disposed in a lower portion (specifically, a lower end portion) of the bearing body 71. The inclined groove portion 83 is formed by cutting out the bearing body 71. The inclined groove portion 83 is inclined in a direction toward the axis O. The lower end portion of the inclined groove portion 83 faces the lubricant supply groove portion 31A disposed in the thrust plate 31 in the direction of the axis O.
The inclined groove portion 83 and the lubricant supply groove portion 31A which are configured in this way are provided. Accordingly, the lubricant to be supplied from the oil separator to the inclined groove portion 83 can be supplied to the radial bearings 19 and 27 located inside in the radial direction of the thrust bearing 29 via the lubricant supply groove portion 31A.
Next, the thrust plate 31 will be described with reference to
The thrust plate 31 is disposed between the thrust bearing 29 and the end plate portion 61A in the direction of the axis O. The thrust plate 31 has a plate body 85, the lubricant supply groove portion 31A, the plurality of second groove portions 31B, and a hole 87.
The plate body 85 is a ring-shaped member. The plate body 85 has one surface 85a and the other surface 85b which are perpendicular to the X-direction.
The one surface 85a is a surface located on the motor housing space 41A side. The one surface 85a is in contact with the second surface 71b of the bearing body 71.
The other surface 85b is a surface located on a side opposite to the one surface 85a. The other surface 85b is in contact with the end plate portion 61A.
The lubricant supply groove portion 31A is disposed in a lower portion (specifically, a lower end portion) of the plate body 85. The lubricant supply groove portion 31A extends from the one surface 85a to the other surface 85b. The lubricant supply groove portion 31A is located to face the inclined groove portion 83 in the direction of the axis O. The lubricant supply groove portion 31A guides the lubricant supplied from the oil separator to the inclined groove portion 83.
The second groove portion 31B is disposed in a portion facing the first groove portion 74 in the outer peripheral portion of the plate body 85 (refer to
The second groove portion 31B configured in this way is provided. Accordingly, the pressure loss of the fluid can be reduced when the fluid passes through the thrust plate 31.
The plurality (two in a case of
The hole 87 is a hole for inserting a screw or a bolt used when the thrust plate 31 is fixed to the thrust bearing 29.
Referring to
According to the scroll compressor 10 in the present embodiment, each of the flow paths 47 penetrating the bearing holder 44 in the direction of the axis O is disposed in the portion corresponding to the formation position of the plurality of stator groove portions 57A in the bearing holder 44. In this manner, the fluid and the lubricant which pass through the stator groove portion 57A are likely to be guided to the flow path 47. Therefore, the lubricant can be properly supplied, and the pressure loss of the fluid (working fluid) can be reduced when the fluid passes through the flow path 47.
In addition, the first recess portion 72 recessed from one side in the direction of the axis O to the other side in the direction of the axis O is disposed in the portion facing the flow path 47 in the thrust bearing 29. In this manner, the fluid and the lubricant which pass through the flow path 47 can be guided into and retained inside the first recess portion 72.
Furthermore, there is provided the first groove portion 74 disposed in the outer peripheral portion of the first recess portion 72, extending from the bottom surface 72a of the first recess portion 72 to the second surface 71b in the direction of the axis O, and communicating with the first recess portion 72. In this manner, the pressure loss of the fluid can be reduced when the fluid passes through the thrust bearing 29.
Hitherto, the preferred embodiment according to the present invention has been described in detail. However, the present invention is not limited to the specific embodiment. The present invention can be modified and changed in various ways within the scope of the gist of the present invention disclosed in the appended claims.
The present invention is applicable to a scroll compressor.
Number | Date | Country | Kind |
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JP2017-162570 | Aug 2017 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2018/025144 | 7/3/2018 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
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WO2019/039095 | 2/28/2019 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
20040124731 | Kimura | Jul 2004 | A1 |
20040197209 | Kitaura | Oct 2004 | A1 |
20090148314 | Koitabashi et al. | Jun 2009 | A1 |
20150303762 | Hagita et al. | Oct 2015 | A1 |
Number | Date | Country |
---|---|---|
63117186 | May 1988 | JP |
1-290991 | Nov 1989 | JP |
3-246388 | Nov 1991 | JP |
8-61255 | Mar 1996 | JP |
8-105392 | Apr 1996 | JP |
2014-88852 | May 2014 | JP |
5518169 | Jun 2014 | JP |
2016-77063 | May 2016 | JP |
2016151264 | Aug 2016 | JP |
WO 2006106753 | Oct 2006 | WO |
WO-2007123015 | Nov 2007 | WO |
Entry |
---|
International Search Report for International Application No. PCT/JP2018/025144, dated Sep. 18, 2018, with English translation. |
Written Opinion of the International Searching Authority for International Applicaiton No. PCT/JP2018/025144, dated Sep. 18, 2018, with English translation. |
Number | Date | Country | |
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20200173443 A1 | Jun 2020 | US |