The present disclosure relates to a scroll compressor.
In general, a scroll compressor includes a tubular housing. The scroll compressor includes a rotary shaft, a fixed scroll, an orbiting scroll, compression chambers, and a discharge chamber. The rotary shaft is rotatably supported by the housing. The fixed scroll is accommodated in the housing. The fixed scroll is fixed to the housing. The orbiting scroll orbits as the rotary shaft rotates. The compression chambers are defined between the fixed scroll and the orbiting scroll. Refrigerant drawn in from the outside is compressed in the compression chambers. The refrigerant compressed in the compression chambers is discharged into the discharge chamber.
Such a scroll compressor includes an oil passage for returning oil separated from the refrigerant discharged into the discharge chamber to the compression chambers. For example, Japanese Laid-Open Patent Publication No. 2020-165362 discloses an oil passage extending through a fixed scroll. The oil separated from the refrigerant is then returned to the outermost peripheral portion of the compression chambers in a decompressed state via the oil passage. The oil returned to the compression chambers contributes to lubrication between the fixed scroll and the orbiting scroll.
In a case in which an oil passage extends through a fixed scroll, the layout of the oil passage is limited due to the need for disposing the oil passage in a thick portion of the fixed scroll. Therefore, depending on the position of the oil passage, it may be difficult to smoothly return the oil to the compression chambers. This results in poor lubrication between the fixed scroll and the orbiting scroll, thus reducing the reliability of the scroll compressor.
This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
In one general aspect, a scroll compressor includes a housing, a rotary shaft rotatably supported by the housing, a fixed scroll accommodated in the housing and fixed to the housing, an orbiting scroll that orbits as the rotary shaft rotates, a compression chamber defined between the fixed scroll and the orbiting scroll, a discharge chamber, and an oil passage. A refrigerant drawn in from an outside is compressed in the compression chamber. The refrigerant compressed in the compression chamber is discharged into the discharge chamber. An outer peripheral space connected to the compression chamber is defined between an outer peripheral surface of the fixed scroll and an inner peripheral surface of the housing. Oil separated from the refrigerant discharged into the discharge chamber is guided to the outer peripheral space through the oil passage.
Other features and aspects will be apparent from the following detailed description, the drawings, and the claims.
Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.
This description provides a comprehensive understanding of the methods, apparatuses, and/or systems described. Modifications and equivalents of the methods, apparatuses, and/or systems described are apparent to one of ordinary skill in the art. Sequences of operations are exemplary, and may be changed as apparent to one of ordinary skill in the art, except for operations necessarily occurring in a certain order. Descriptions of functions and constructions that are well known to one of ordinary skill in the art may be omitted.
Exemplary embodiments may have different forms, and are not limited to the examples described. However, the examples described are thorough and complete, and convey the full scope of the disclosure to one of ordinary skill in the art.
In this specification, “at least one of A and B” should be understood to mean “only A, only B, or both A and B.”
Hereinafter, a scroll compressor 10 according to an embodiment will be described with reference to
<Basic Configuration of Scroll Compressor 10>
As illustrated in
The motor housing member 12 includes a plate-shaped end wall 12a and a cylindrical peripheral wall 12b. The peripheral wall 12b extends in a tubular shape from the outer periphery of the end wall 12a. The axial direction of the peripheral wall 12b agrees with the axial direction of the rotary shaft 15. The motor housing member 12 includes internal thread holes 12c. Each internal thread hole 12c opens at the opening end of the peripheral wall 12b. In
The motor housing member 12 includes a cylindrical boss portion 12d. The boss portion 12d protrudes from the center of the inner surface of the end wall 12a. A first end in the axial direction of the rotary shaft 15 is inserted in the boss portion 12d. The scroll compressor 10 includes a bearing 16. The bearing 16 is, for example, a rolling-element bearing. The bearing 16 is disposed between the inner peripheral surface of the boss portion 12d and the outer peripheral surface of the first end portion of the rotary shaft 15. The first end of the rotary shaft 15 is rotatably supported by the motor housing member 12 with the bearing 16.
The shaft support housing member 13 includes a plate-shaped end wall 17 and a cylindrical peripheral wall 18. The peripheral wall 18 extends in a tubular shape from the outer periphery of the end wall 17. The axial direction of the peripheral wall 18 agrees with the axial direction of the rotary shaft 15. The shaft support housing member 13 includes an annular flange wall 19. The flange wall 19 extends outward in the radial direction of the rotary shaft 15 from the end of the outer peripheral surface of the peripheral wall 18 opposite to the end wall 17.
The shaft support housing member 13 includes a circular insertion hole 17a. The insertion hole 17a opens at the center of the end wall 17. The insertion hole 17a extends through the end wall 17 in the thickness direction. The rotary shaft 15 is inserted in the insertion hole 17a. A second end in the axial direction of the rotary shaft 15 includes an end face 15e. The end face 15e is located inside the peripheral wall 18.
The scroll compressor 10 includes a bearing 21. The bearing 21 is, for example, a rolling-element bearing. The bearing 21 is disposed between the inner peripheral surface of the peripheral wall 18 and the outer peripheral surface of the rotary shaft 15. The rotary shaft 15 is rotatably supported by the shaft support housing member 13 with the bearing 21. Hence the shaft support housing member 13 rotatably supports the rotary shaft 15. In this manner, the rotary shaft 15 is rotatably supported by the housing 11.
The shaft support housing member 13 includes bolt insertion holes 19a. Each bolt insertion hole 19a opens at the outer periphery of the flange wall 19. Each bolt insertion hole 19a extends through the flange wall 19 in the thickness direction. The bolt insertion holes 19a in the flange wall 19 are connected to the internal thread holes 12c in the motor housing member 12, respectively. In
The scroll compressor 10 includes a motor chamber 20. The motor chamber 20 is defined by a motor housing member 12 and a shaft support housing member 13. The motor housing member 12 defines the motor chamber 20 together with the shaft support housing member 13. In this manner, the motor chamber 20 is defined in the housing 11. The motor chamber 20 is connected to with the inlet 12h. The refrigerant drawn through the inlet 12h is drawn into the motor chamber 20. Therefore, the motor chamber 20 is a suction pressure zone.
The scroll compressor 10 includes a motor 22. The motor 22 is accommodated in the motor chamber 20. The motor 22 includes a cylindrical stator 23 and a cylindrical rotor 24. The rotor 24 is disposed inside the stator 23. The rotor 24 rotates integrally with the rotary shaft 15. The stator 23 surrounds the rotor 24. The rotor 24 includes a rotor core 24a fixed to the rotary shaft 15 and permanent magnets (not illustrated) provided on the rotor core 24a.
The stator 23 includes a cylindrical stator core 23a and a motor coil 23b. The stator core 23a is fixed to the inner peripheral surface of the peripheral wall 12b of the motor housing member 12. The motor coil 23b is wound around the stator core 23a. Electric power controlled by an inverter (not illustrated) is supplied to the motor coil 23b, whereby the rotor 24 rotates. As a result, the rotary shaft 15 rotates integrally with the rotor 24. Thus, the motor 22 rotates the rotary shaft 15.
The scroll compressor 10 includes a compression mechanism Cl. The compression mechanism Cl includes a fixed scroll 25 and an orbiting scroll 26. Accordingly, the scroll compressor 10 includes the fixed scroll 25 and the orbiting scroll 26. The compression mechanism Cl is of a scroll type. The orbiting scroll 26 orbits with respect to the fixed scroll 25 as the rotary shaft 15 rotates.
As illustrated in
As illustrated in
The discharge port 25h opens in the bottom surface of the first discharge chamber forming recess 41. As illustrated in
The orbiting scroll 26 includes an orbiting base plate 26a and an orbiting volute wall 26b. The orbiting base plate 26a is a disc. The orbiting base plate 26a faces the fixed base plate 25a. The orbiting volute wall 26b extends from the orbiting base plate 26a toward the fixed base plate 25a. The orbiting volute wall 26b meshes with the fixed volute wall 25b. The orbiting scroll 26 is located inside the outer peripheral wall 25c. The orbiting scroll 26 orbits inside the outer peripheral wall 25c. The distal end face of the fixed volute wall 25b is in contact with the orbiting base plate 26a. The distal end face of the orbiting volute wall 26b is in contact with the fixed base plate 25a.
The scroll compressor 10 includes compression chambers 27. The compression chambers 27 are defined by the fixed base plate 25a, the fixed volute wall 25b, the orbiting base plate 26a, and the orbiting volute wall 26b. Accordingly, the compression chambers 27 are defined between the fixed scroll 25 and the orbiting scroll 26. The refrigerant drawn in from the outside is compressed in the compression chambers 27.
The orbiting base plate 26a includes a cylindrical boss portion 26c. The boss portion 26c protrudes from an end face 26e of the orbiting base plate 26a opposite to the fixed base plate 25a. The axial direction of the boss portion 26c agrees with the axial direction of the rotary shaft 15. The orbiting base plate 26a includes groove portions 26d. The groove portions 26d are arranged around the boss portion 26c on the end face 26e of the orbiting base plate 26a. The groove portions 26d are arranged at predetermined intervals in the circumferential direction of the rotary shaft 15. In
The scroll compressor 10 includes an elastic plate 30. The elastic plate 30 has an annular shape. The elastic plate 30 is sandwiched between the end face 13e of the shaft support housing member 13 and the opening end face of the outer peripheral wall 25c. The elastic plate 30 constantly urges the orbiting scroll 26 toward the fixed scroll 25.
The scroll compressor 10 includes an eccentric shaft 31. The eccentric shaft 31 protrudes toward the orbiting scroll 26 from a position eccentric to an axis L1 of the rotary shaft 15 on the end face 15e of the rotary shaft 15. The eccentric shaft 31 is integrally formed with the rotary shaft 15. The axial direction of the eccentric shaft 31 agrees with the axial direction of the rotary shaft 15. The eccentric shaft 31 is inserted in the boss portion 26c.
The scroll compressor 10 includes a balance weight 32 and a bushing 33. The bushing 33 is fitted to the outer peripheral surface of the eccentric shaft 31. The balance weight 32 is integrated with the bushing 33. The balance weight 32 is integrally formed with the bushing 33. The balance weight 32 is accommodated in the peripheral wall 18 of the shaft support housing member 13. The orbiting scroll 26 is supported by the eccentric shaft 31 with the bushing 33 and the rolling-element bearing 34 to be rotatable with respect to the eccentric shaft 31.
Rotation of the rotary shaft 15 is transmitted to the orbiting scroll 26 via the eccentric shaft 31, the bushing 33, and the rolling-element bearing 34. Thereby, the orbiting scroll 26 rotates. Then, the pins 29 come into contact with the inner peripheral surfaces of the respective ring members 28, whereby the rotation of the orbiting scroll 26 is prevented, and only the orbiting motion of the orbiting scroll 26 is allowed. As a result, the orbiting scroll 26 makes an orbiting motion while the orbiting volute wall 26b is in contact with the fixed volute wall 25b. As the volume of each compression chamber 27 decreases with the orbiting motion of the orbiting scroll 26, the refrigerant is compressed in the compression chamber 27. The orbiting scroll 26 orbits inside the outer peripheral wall 25c as the rotary shaft 15 rotates. The balance weight 32 cancels a centrifugal force acting on the orbiting scroll 26 when the orbiting scroll 26 makes an orbiting motion. This reduces the imbalance amount of the orbiting scroll 26.
As illustrated in
The discharge housing member 14 includes bolt insertion holes 14c. The bolt insertion holes 14c open in the peripheral wall 14b. In
Bolts B1 passing through the respective bolt insertion holes 14c pass through the respective bolt insertion holes 19a in the flange wall 19 and are screwed in the respective internal thread holes 12c in the motor housing member 12. Thereby, the shaft support housing member 13 is coupled to the peripheral wall 12b of the motor housing member 12, and the discharge housing member 14 is coupled to the flange wall 19 of the shaft support housing member 13. Hence the motor housing member 12, the shaft support housing member 13, and the discharge housing member 14 are disposed in that order in the axial direction of the rotary shaft 15. The fixed scroll 25 is sandwiched between the end wall 14a of the discharge housing member 14 and the shaft support housing member 13. In this manner, the fixed scroll 25 is fixed to the housing 11. The discharge housing member 14 is coupled to the fixed scroll 25.
As illustrated in
The inner end face 14e of the end wall 14a includes a second annular end face 141 and a second connection end face 142. The second annular end face 141 has an annular shape extending along the outer periphery of the inner end face 14e of the end wall 14a. The second connection end face 142 has a shape of an elongated strip. The second connection end face 142 is connected to the second annular end face 141 and extends between the second discharge chamber forming recess 42 and the second oil reservoir chamber forming recess 52.
As illustrated in
<Outer Peripheral Space S1>
As illustrated in
The scroll compressor 10 includes a suction passage 35. The suction passage 35 includes first grooves 36, first holes 37, and second grooves 38. The first groove 36 is disposed in the inner peripheral surface of the peripheral wall 12b. The first groove 36 opens at an opening end of the peripheral wall 12b. The first hole 37 is disposed at the outer periphery of the flange wall 19 of the shaft support housing member 13. The first hole 37 extends through the flange wall 19 in the thickness direction. Each first hole 37 is connected to the corresponding first groove 36. The second groove 38 is provided in the inner peripheral surface of the peripheral wall 14b of the discharge housing member 14. Each second groove 38 is connected to the corresponding first hole 37. Each second groove 38 defines a part of the outer peripheral space S1.
A suction port 39 opens in the outer peripheral wall 25c of the fixed scroll 25. The suction port 39 extends through the outer peripheral wall 25c in the thickness direction. The suction port 39 is connected to the outer peripheral space S1. The suction port 39 is connected to the outermost peripheral portion of the compression chamber 27. Thus, the outer peripheral space S1 is connected to the compression chamber 27 via the suction port 39.
The refrigerant in the motor chamber 20 passes through the first groove 36, the first hole 37, the second groove 38, and the suction port 39 and is drawn into the compression chambers 27. Hence the refrigerant is drawn into the compression chambers 27 through the suction port 39. The first groove 36, the first hole 37, the second groove 38, and the suction port 39 are suction pressure zones through which the refrigerant drawn into the compression chambers 27 flows. Therefore, the outer peripheral space S1 is a suction pressure zone. The refrigerant drawn into the compression chambers 27 is compressed in the compression chamber 27 by the orbiting motion of the orbiting scroll 26. In this manner, the compression mechanism Cl compresses the refrigerant drawn into the housing 11.
<Gasket 70>
As illustrated in
The gasket 70 includes a discharge chamber connection hole 70a and an oil reservoir chamber connection hole 70b. The discharge chamber connection hole 70a has substantially the same shape as the first discharge chamber forming recess 41 and the second discharge chamber forming recess 42. The oil reservoir chamber connection hole 70b has substantially the same shape as the first oil reservoir chamber forming recess 51 and the second oil reservoir chamber forming recess 52.
The gasket 70 includes a first seal portion 71 and a second seal portion 72. The first seal portion 71 has an annular shape. The first seal portion 71 extends along the first annular end face 251 and the second annular end face 141. The first seal portion 71 is interposed between the first annular end face 251 and the second annular end face 141. The first seal portion 71 provides a seal between the first annular end face 251 and the second annular end face 141. Therefore, the gasket 70 provides a seal between the second annular end face 141 and the fixed base plate 25a.
The opposite ends of the second seal portion 72 are connected to two different places in the circumferential direction of the first seal portion 71. The second seal portion 72 has a shape of an elongated strip. The second seal portion 72 extends along the first connection end face 252 and the second connection end face 142. The second seal portion 72 is interposed between the first connection end face 252 and the second connection end face 142. The second seal portion 72 provides a seal between the first connection end face 252 and the second connection end face 142. The second seal portion 72 separates the discharge chamber connection hole 70a and the oil reservoir chamber connection hole 70b from each other. The second seal portion 72 includes a through hole 73.
As illustrated in
The first oil reservoir chamber forming recess 51 and the second oil reservoir chamber forming recess 52 are connected to each other via the oil reservoir chamber connection hole 70b. An oil reservoir chamber 50 is defined by the first oil reservoir chamber forming recess 51 and the second oil reservoir chamber forming recess 52. Accordingly, the scroll compressor 10 includes the oil reservoir chamber 50. The oil separated from the refrigerant discharged into the discharge chamber 40 is stored in the oil reservoir chamber 50. The discharge chamber 40 and the oil reservoir chamber 50 are defined by the fixed scroll 25 and the discharge housing member 14. The discharge housing member 14 defines the discharge chamber 40 and the oil reservoir chamber 50 together with the fixed base plate 25a. The discharge chamber 40 and the oil reservoir chamber 50 are defined by the discharge housing member 14 and the fixed base plate 25a inside the second annular end face 141.
The second seal portion 72 of the gasket 70 provides a seal between the discharge chamber 40 and the oil reservoir chamber 50. Thus, the gasket 70 provides a seal between the discharge chamber 40 and the oil reservoir chamber 50. The scroll compressor 10 according to the present embodiment is mounted on a vehicle such that the oil reservoir chamber 50 is positioned below the discharge chamber 40.
As illustrated in
An inner cylinder 63 is fitted into the oil separation chamber 60. The axial direction of the inner cylinder 63 agrees with the radial direction of the rotary shaft 15. The first end of the inner cylinder 63 is connected to the discharge outlet 62. The second end of the inner cylinder 63 is connected to the side opposite to the discharge outlet 62 in the oil separation chamber 60. As illustrated in
The discharge housing member 14 includes an oil discharge hole 65. The first end of the oil discharge hole 65 is connected to the side opposite to the discharge outlet 62 in the oil separation chamber 60. As illustrated in
As illustrated in
The refrigerant from which the oil has been separated flows into the inner cylinder 63 and passes through the inner cylinder 63. The refrigerant having passed through the inner cylinder 63 flows out to an external refrigerant circuit (not shown) via the discharge outlet 62. The oil separated from the refrigerant in the oil separation chamber 60 flows toward the oil discharge hole 65 by its own weight. Then, the oil flowing toward the oil discharge hole 65 is discharged into the oil reservoir chamber 50 via the oil discharge hole 65 and the through hole 73, and is stored in the oil reservoir chamber 50.
<Oil Passage 80>
As illustrated in
As illustrated in
The position of the opening of the connection passage 82 at the outer edge of the fixed base plate 25a is the same phase position in the circumferential direction of the rotary shaft 15 as that of the opening of the suction port 39 connected to the outer peripheral space S1. Therefore, the oil passage 80 is connected to the outer peripheral space S1 such that the opening of the oil passage 80 connected to the outer peripheral space S1 is at the same phase position in the circumferential direction of the rotary shaft 15 as the opening of the suction port 39 connected to the outer peripheral space S1.
Next, operation of the present embodiment will be described.
The oil stored in the oil reservoir chamber 50 is returned to the outer peripheral space S1 via the oil passage 80. At this time, with the oil passing through the restriction groove 81, the oil stored in the oil reservoir chamber 50 is returned to the outer peripheral space S1 in a decompressed state via the oil passage 80. The oil returned to the outer peripheral space S1 returns from the inside of the motor chamber 20 to the compression chamber 27 via the suction port 39 together with the refrigerant passing through the first groove 36, the first hole 37, and the second groove 38. The oil returned to the compression chamber 27 contributes to lubrication between the fixed scroll 25 and the orbiting scroll 26.
The above embodiment has the following advantages.
[Modifications]
The above-described embodiment may be modified as follows. The above-described embodiment and the following modifications can be combined if the combined modifications remain technically consistent with each other.
As in a first modification illustrated in
As in a second modification illustrated in
As in a third modification illustrated in
For example, the fixed scroll 25 may include the oil passage 80. A connection path 84 may be provided in the outer peripheral wall 25c of the fixed scroll 25. The connection path 84 extends in the axial direction of the outer peripheral wall 25c. The first end of the connection path 84 is connected to the outer peripheral space S1. The second end of the connection path 84 opens in the bottom surface of one passage recess 25g of the passage recesses 25g. The connection path 84 is connected to the inside of one passage recess 25g of the passage recesses 25g. A restriction member 83 is provided in the connection path 84. In this manner, a restriction may be provided in the oil flow path between the outer peripheral space S1 and the compression chamber 27 to set the outer peripheral space S1 as a discharge pressure zone.
With this configuration, the pressure in the outer peripheral space S1 can be made equal to the pressure in the oil reservoir chamber 50, so that the oil stored in the oil reservoir chamber 50 smoothly flows to the outer peripheral space S1 via the oil passage 80. With the restriction member 83 being provided in the connection path 84, the oil returned to the outer peripheral space S1 is stably stored in the outer peripheral space S1.
The gasket 70 does not necessarily need to include the restriction groove 81, and for example, a restriction groove may be provided in the first annular end face 251 of the fixed scroll 25. For example, a restriction groove may be provided in the second annular end face 141 of the discharge housing member 14. In this case, the connection passage 82 is provided in the second annular end face 141. In this manner, the oil passage 80 may be provided between the second annular end face 141 and the fixed base plate 25a and connect the oil reservoir chamber 50 and the outer peripheral space S1.
A connection passage connecting the restriction groove 81 and the outer peripheral space S1 may be provided in the gasket 70.
The phase position of the opening connected to the outer peripheral space S1 in the oil passage 80 may be shifted in the circumferential direction of the rotary shaft 15 with respect to the opening connected to the outer peripheral space S1 in the suction port 39. With this configuration, for example, the oil returned from the oil passage 80 to the outer peripheral space S1 is readily stored once in the outer peripheral space S1 instead of directly flowing to the suction port 39. Therefore, it is possible to readily cause the outer peripheral space S1 to function as an oil reservoir space in which oil is stored.
The gasket 70 does not necessarily need to include the restriction groove 81, and for example, the elastic plate 30 may include the restriction groove. In this case, the oil stored in the oil reservoir chamber 50 passes through the hole extending through the fixed scroll 25 and the restriction groove provided in the elastic plate 30, and returns to the outer peripheral space S1.
The number of suction ports 39 is not particularly limited. For example, the number of oil passages 80 may be changed in accordance with the number of suction ports 39. For example, the oil passages 80 may be configured to be connected to the outer peripheral space S1 such that the openings of the respective oil passages 80 connected to the outer peripheral space S1 are at the same phase positions in the circumferential direction of the rotary shaft 15 as the openings of the respective suction ports 39 connected to the outer peripheral space S1.
The peripheral wall 12b of the motor housing member 12 may surround the fixed scroll 25. The outer peripheral space S1 may be defined between the outer peripheral surface of the outer peripheral wall 25c and the inner peripheral surface of the peripheral wall 12b. In short, the outer peripheral space S1 may be defined between the outer peripheral surface of the fixed scroll 25 and the inner peripheral surface of the housing 11.
The outer peripheral space S1 does not necessarily need to annularly extend around the fixed scroll 25. In short, the outer peripheral space S1 only needs to be a space defined between the outer peripheral surface of the fixed scroll 25 and the inner peripheral surface of the housing 11 and connected to the compression chamber 27.
The scroll compressor 10 does not necessarily need to be a type driven by the motor 22 and may be, for example, a type driven by an engine of a vehicle.
The scroll compressor 10 has been used in a vehicle air conditioner but is not limited thereto. In short, the scroll compressor 10 only needs to compress the refrigerant, and the application of the scroll compressor 10 can be changed as appropriate.
Various changes in form and details may be made to the examples above without departing from the spirit and scope of the claims and their equivalents. The examples are for the sake of description only, and not for purposes of limitation. Descriptions of features in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if sequences are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined differently, and/or replaced or supplemented by other components or their equivalents. The scope of the disclosure is not defined by the detailed description, but by the claims and their equivalents. All variations within the scope of the claims and their equivalents are included in the disclosure.
Number | Date | Country | Kind |
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2022-051147 | Mar 2022 | JP | national |
Number | Name | Date | Kind |
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20180172004 | Lee | Jun 2018 | A1 |
20190101119 | Hattori | Apr 2019 | A1 |
20210062808 | Hattori | Mar 2021 | A1 |
Number | Date | Country |
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102018107460 | Oct 2018 | DE |
2000-018180 | Jan 2000 | JP |
2020-033989 | Mar 2020 | JP |
2020-165362 | Oct 2020 | JP |
Entry |
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English translation of DE 1020181017460 by PE2E, Jun. 28, 2023. |
Number | Date | Country | |
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20230304493 A1 | Sep 2023 | US |