Patent Grant
12031546
The present disclosure relates to a scroll casing and a centrifugal compressor including the scroll casing.
A centrifugal compressor used in a compressor part of a vehicle or marine turbocharger provides kinetic energy to a fluid through rotation of the impeller and discharges the fluid radially outward to obtain a pressure increase of the fluid by using the centrifugal force. Such a centrifugal compressor is provided with various features to meet the need to improve the pressure ratio and the efficiency in a broad operational range.
Generally, a centrifugal compressor is equipped with a scroll casing having a scroll part which forms a spiral scroll passage. The cross-section of the scroll passage (scroll cross-section) is formed in a near-circular shape over the entire circumference of the scroll passage. One known example of a conventional centrifugal compressor has a scroll cross-section that includes a first arc portion having a first curvature radius and a second arc portion having a second curvature radius different from the first curvature radius.
If the scroll cross-section is distorted, pressure loss may occur in the scroll passage. For this reason, the scroll cross-section is generally made closer to a perfect circle. One of the measures to make the scroll cross-section closer to a perfect circle is to form most of the scroll cross-section with the first arc portion and the rest of the scroll cross-section with the second arc portion. The second arc portion connects one end of the first arc portion and the tip-side passage surface of the diffuser passage. In this case, a dramatic change in curvature occurs between the first arc portion and the second arc portion, which may cause pressure loss in the scroll passage.
Patent Document 1: JP6053993B
Another measure to make the scroll cross-section closer to a perfect circle is to reduce the difference between the first curvature radius and the second curvature radius so that the scroll cross-section has a shape close to a circle as a whole. In this case, since the change in curvature between the first arc portion and the second arc portion is gentle, the occurrence of pressure loss in the scroll passage can be suppressed as compared to the above-described measure, and the efficiency of the centrifugal compressor can be improved. To further improve the efficiency of the centrifugal compressor, it is required to suppress the occurrence of pressure loss in the scroll passage more effectively than this measure.
Incidentally, Patent Document 1 discloses a scroll part of a centrifugal compressor having a scroll cross-section that includes a first arc portion having a first curvature radius, a second arc portion having a second curvature radius, and a third arc portion having a third curvature radius. In the scroll part of Patent Document 1, the second arc portion has a flatter shape than the first arc portion and the third arc portion in order to make it easier to guide a fluid introduced into the scroll passage to the inner peripheral side of the scroll passage, as compared to the case where the cross-section of the scroll section has a near-circular shape. Thus, in the scroll part of Patent Document 1, the cross-section of the scroll passage is intentionally shaped different from a circular shape. Therefore, Patent Document 1 has low relevance to the present disclosure.
In view of the above, an object of at least one embodiment of the present disclosure is to provide a scroll casing and a centrifugal compressor including the scroll casing whereby it is possible to suppress the occurrence of pressure loss in the scroll passage.
A scroll casing of a centrifugal compressor according to the present disclosure includes a scroll part forming a scroll passage of the centrifugal compressor. On an inner peripheral surface of the scroll part, when a connection position with a hub-side passage surface of a diffuser passage of the centrifugal compressor is defined as a first position, an outermost end in a radial direction of the centrifugal compressor is defined as a second position, a foremost end in an axial direction of the centrifugal compressor is defined as a third position, an innermost end in the radial direction is defined as a fourth position, and an end position on one-direction side which is a side from the first position toward the fourth position along the inner peripheral surface of the scroll part is defined as a fifth position, the scroll part has a near-circular scroll cross-section which includes at least a first arc portion extending from the first position to the one-direction side, a second arc portion formed on the one-direction side of the first arc portion so as to include at least a part of a region between the second position and the fourth position, and a third arc portion formed on the one-direction side of the second arc portion so as to include at least the fifth position, and satisfies a relationship of R2>R3, where R2 is a curvature radius of the second arc portion, and R3 is a curvature radius of the third arc portion.
A centrifugal compressor according to the present disclosure includes the above-described scroll casing.
At least one embodiment of the present disclosure provides a scroll casing and a centrifugal compressor including the scroll casing whereby it is possible to suppress the occurrence of pressure loss in the scroll passage.
Embodiments of the present disclosure will be described below with reference to the accompanying drawings. It is intended, however, that unless particularly identified, dimensions, materials, shapes, relative positions, and the like of components described in the embodiments shall be interpreted as illustrative only and not intended to limit the scope of the present disclosure.
For instance, an expression of relative or absolute arrangement such as “in a direction”, “along a direction”, “parallel”, “orthogonal”, “centered”, “concentric” and “coaxial” shall not be construed as indicating only the arrangement in a strict literal sense, but also includes a state where the arrangement is relatively displaced by a tolerance, or by an angle or a distance whereby it is possible to achieve the same function.
For instance, an expression of an equal state such as “same” “equal” and “uniform” shall not be construed as indicating only the state in which the feature is strictly equal, but also includes a state in which there is a tolerance or a difference that can still achieve the same function.
Further, for instance, an expression of a shape such as a rectangular shape or a cylindrical shape shall not be construed as only the geometrically strict shape, but also includes a shape with unevenness or chamfered corners within the range in which the same effect can be achieved.
On the other hand, an expression such as “comprise”, “include”, “have”, “contain” and “constitute” are not intended to be exclusive of other components.
The same features can be indicated by the same reference numerals and not described in detail.
(Centrifugal Compressor and Turbocharger)
As shown in
The centrifugal compressor 1 can be applied to, for example, turbochargers 10 for automobile, marine, or power generation use, other industrial centrifugal compressors, and blowers, etc. In the illustrated embodiment, the centrifugal compressor 1 is mounted in a turbocharger 10. As shown in
In the illustrated embodiment, as shown in
Hereinafter, for example as shown in
Y. In the axial direction X, the upstream side with respect to the intake direction of the centrifugal compressor 1, i.e., the side where a fluid introduction port 33 is positioned with respect to the impeller 2 (left side in the figure) is referred to as the front side XF. Further, in the axial direction X, the downstream side with respect to the intake direction of the centrifugal compressor 1, i.e., the side where the impeller 2 is positioned with respect to the fluid introduction port 33 (right side in the figure) is referred to as the rear side XR.
In the illustrated embodiment, as shown in
As shown in
The turbocharger 10 rotates the turbine rotor 13 by the exhaust gas introduced from an exhaust gas generation device (not shown, e.g., internal combustion engine such as engine) into the turbine casing 14 through the exhaust gas introduction port 141. Since the impeller 2 is mechanically connected to the turbine rotor 13 via the rotational shaft 12, the impeller 2 rotates in conjunction with the rotation of the turbine rotor 13. By rotating the impeller 2, the turbocharger 10 compresses the fluid introduced into the scroll casing 3 through the fluid introduction port 33 and sends it to a supply destination (e.g., internal combustion engine such as engine) through the fluid discharge port 34.
(Impeller)
As shown in
(Scroll Casing)
In the illustrated embodiment, as shown in
The intake passage part 37 has an inner wall surface 370 forming the intake passage 36. The inner wall surface 370 extends along the axial direction X, and the fluid introduction port 33 is formed at the end on the front side XF. The scroll part 32 has an inner peripheral surface 320 forming the scroll passage 31.
Further, in the illustrate embodiment, as shown in
The shroud part 38 is disposed between the intake passage part 37 and the scroll part 32. The shroud surface 35 of the shroud part 38 forms a portion of the impeller chamber 39 on the front side XF. Further, the shroud part 38 has a tip-side passage surface 41 forming a portion of the diffuser passage 40 on the front side XF and connecting the shroud surface 35 and one end of the inner peripheral surface 320 of the scroll part 32. In the illustrated embodiment, the bearing casing 16 has an impeller chamber forming surface 161 disposed on the rear side XR of the shroud surface 35 and forming a portion of the impeller chamber 39 on the rear side XR, and a hub-side passage surface 162 disposed on the rear side XR of the tip-side passage surface 41 so as to face the tip-side passage surface 41 and connecting the impeller chamber forming surface 161 and the other end (first position P1 which will be described later) of the inner peripheral surface 320 of the scroll part 32. In a cross-section along the axis CA as shown in
The fluid introduced into the scroll casing 3 flows through the intake passage 36 to the rear side XR and then is sent to the impeller 2. The fluid sent to the impeller 2 flows through the diffuser passage 40 and the scroll passage 31 in this order, and then is discharged to the outside of the scroll casing 3 through the fluid discharge port 34.
(Scroll Cross-Section)
Hereinafter, as shown in
As shown in
The curvature radius of the first arc portion 5 is defined as R1, the curvature radius of the second arc portion 6 is defined as R2, and the curvature radius of the third arc portion 7 is defined as R3. In the embodiments shown in
As shown in
Hereinafter, the upstream end in the one-direction UD may simply be referred to as “upstream end”, and the downstream end in the one-direction UD may simply be referred to as “downstream end”.
In the embodiment shown in
The upstream end 51 of the first arc portion 5 of the scroll part 32 (32A) is connected to the hub-side passage surface 162 at the first position P1, and the downstream end 52 thereof is connected to the upstream end 61 of the second arc portion 6 at the second position P2. The upstream end 71 of the third arc portion 7 is connected to the downstream end 62 of the second arc portion 6 at the third position P3, and the downstream end 72 thereof is at the fifth position P5.
In the embodiment shown in
The upstream end 51 of the first arc portion 5 of the scroll part 32 (32B) is connected to the hub-side passage surface 162 at the first position P1, and the downstream end 52 thereof is connected to the upstream end (rear end) 81 of the first straight portion 8 at the position P6 upstream of the second position P2 in the one-direction UD. The upstream end 61 of the second arc portion 6 is connected to the downstream end (front end) of the first straight portion 8 at the second position P2, and the downstream end 62 thereof is connected to the upstream end 71 of the third arc portion 7 at the fourth position P4. The downstream end 72 of the third arc portion 7 is at the fifth position P5.
In some embodiments, the near-circular scroll cross-section 42 of the scroll part 32 (32A, 32B) may further include a second straight portion (not shown) connecting the second arc portion 6 and the third arc portion 7.
As shown in
The upstream end 51A of the first arc portion 5A is connected to the hub-side passage surface 162 at the first position P1, and the downstream end 52A thereof is connected to the upstream end 61A of the second arc portion 6A. The downstream end 62A of the second arc portion 6A is at the fifth position P5.
As shown in
For example, as shown in
According to the above configuration, the scroll part 32 (32A, 32B) has the near-circular scroll cross-section 42 that includes the first arc portion 5 including at least the first position P1, the second arc portion 6 formed on the one-direction UD side of the first arc portion 5 so as to include at least a part of the region between the second position P2 and the fourth position P4, and the third arc portion 7 formed on the one-direction UD side of the second arc portion 6 so as to include at least the fifth position P5. In this case, since the near-circular scroll cross-section 42 includes three arc portions (first arc portion 5, second arc portion 6, and third arc portion 7), as compared to the case where the cross-section includes two arc portions (e.g., first arc portion 5A and second arc portion 6A), the difference in curvature radius between the arc portions can be reduced. As a result, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature from the first arc portion 5 to the third arc portion 7 of the near-circular scroll cross-section 42.
In some embodiments, as shown in
In some embodiments, as shown in
In some embodiments, as shown in
In some embodiments, as shown in
In some embodiments, as shown in
When the distance of the outermost end (second position P2) of the scroll passage 31 in the radial direction from the axis CA of the centrifugal compressor 1 is shortened, it may be difficult to directly connect the first arc portion 5 and the second arc portion 6. According to the above configuration, with the first straight portion 8 connecting the first arc portion 5 and the second arc portion 6, the shape in which the first arc portion 5 and the second arc portion 6 are connected can be easily obtained. The first straight portion 8 is preferably as short as possible because the pressure loss in the scroll passage 31 may increase when the first straight portion 8 is long.
In some embodiments, as shown in
According to the above configuration, the near-circular scroll cross-section 42 satisfies a relationship of R2/R1≥0.8. In other words, the curvature radius R2 of the second arc portion 6 has a curvature radius reduction ratio of 20% or less with respect to the curvature radius R1 of the first arc portion 5. When the curvature change amount between the first arc portion 5 and the second arc portion 6 is small, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature between the first arc portion 5 and the second arc portion 6. Further, the near-circular scroll cross-section 42 satisfies a relationship of R3/R2≥0.8. In other words, the curvature radius R3 of the third arc portion 7 has a curvature radius reduction ratio of 20% or less with respect to the curvature radius R2 of the second arc portion 6. When the curvature change amount between the second arc portion 6 and the third arc portion 7 is small, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature between the second arc portion 6 and the third arc portion 7.
In particular, when the near-circular scroll cross-section 42 satisfies a relationship of
R2/R1≥0.9 and R3/R2≥0.9, the effect of reducing pressure loss is almost comparable to the case where the curvature of the inner peripheral surface 320 in the near-circular scroll cross-section 42 continuously decreases toward the one-direction UD side (scroll part 32D).
In some embodiments, as shown in
According to the above configuration, the near-circular scroll cross-section 42 satisfies a relationship of R3/R2≥0.8. In other words, the curvature radius R3 of the third arc portion 7 has a curvature radius reduction ratio of 20% or less with respect to the curvature radius R2 of the second arc portion 6. When the curvature change amount between the second arc portion 6 and the third arc portion 7 is small, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature between the second arc portion 6 and the third arc portion 7.
In particular, when the near-circular scroll cross-section 42 satisfies a relationship of R3/R2≥0.9, the effect of reducing pressure loss is almost comparable to the case where the curvature of the inner peripheral surface 320 in the near-circular scroll cross-section 42 continuously decreases toward the one-direction UD side (scroll part 32E).
In the above-described embodiments, the near-circular scroll cross-section 42 includes three arc portions (first arc portion 5, second arc portion 6, and third arc portion 7) each having a constant curvature radius. However, in some embodiments, as shown in
As shown in
In some embodiments, as shown in
The scroll passage 31 has a smaller scroll cross-sectional area as it is closer to the winding start. Therefore, it may be difficult to form the near-circular scroll cross-section 42 in the vicinity of the winding start. According to the above configuration, since the near-circular scroll cross-section 42 is formed in the range S where the angular position θ is from 120 degrees to 360 degrees, which is easy to form the near-circular scroll cross-section 42, the occurrence of pressure loss in the scroll passage 31 can be sufficiently suppressed. The near-circular scroll cross-section 42 may be formed in a range T where the angular position θ is from 0 degrees to 120 degrees. The near-circular scroll cross-section 42 is preferably formed in the range S and the range T.
In some embodiments, as shown in
As shown in
The present disclosure is not limited to the embodiments described above, but includes modifications to the embodiments described above, and embodiments composed of combinations of those embodiments.
The contents described in the above embodiments would be understood as follows, for instance.
1) A scroll casing (3) of a centrifugal compressor (1) according to at least one embodiment of the present disclosure includes a scroll part (32) forming a scroll passage (31) of the centrifugal compressor. On an inner peripheral surface (320) of the scroll part, when a connection position with a hub-side passage surface (162) of a diffuser passage (40) of the centrifugal compressor is defined as a first position (P1), an outermost end in a radial direction of the centrifugal compressor is defined as a second position (P2), a foremost end in an axial direction of the centrifugal compressor is defined as a third position (P3), an innermost end in the radial direction is defined as a fourth position (P4), and an end position on one-direction (UD) side which is a side from the first position (P1) toward the fourth position (P4) along the inner peripheral surface of the scroll part is defined as a fifth position (P5), the scroll part (32) has a near-circular scroll cross-section (42) which includes at least a first arc portion (5) extending from the first position (P1) to the one-direction side, a second arc portion (6) formed on the one-direction side of the first arc portion (5) so as to include at least a part of a region between the second position (P2) and the fourth position (P4), and a third arc portion (7) formed on the one-direction side of the second arc portion (6) so as to include at least the fifth position (P5), and satisfies a relationship of R2>R3, where R2 is a curvature radius of the second arc portion (6), and R3 is a curvature radius of the third arc portion (7).
According to the above configuration 1), the scroll part (32) has the near-circular scroll cross-section (42) that includes the first arc portion (5) including at least the first position (P1), the second arc portion (6) formed on the one-direction (UD) side of the first arc portion (5) so as to include at least a part of the region between the second position (P2) and the fourth position (P4), and the third arc portion (7) formed on the one-direction side of the second arc portion (6) so as to include at least the fifth position (P5). In this case, since the near-circular scroll cross-section (42) includes three arc portions (first arc portion 5, second arc portion 6, and third arc portion 7), as compared to the case where the cross-section includes two arc portions, the difference in curvature radius between the arc portions can be reduced. As a result, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature from the first arc portion (5) to the third arc portion (7) of the near-circular scroll cross-section (42).
Additionally, according to the above configuration 1), the curvature radius R2 of the second arc portion (6) is larger than the curvature radius R3 of the third arc portion (7). In this case, the change in curvature between the second arc portion (6) and the third arc portion (7) in the near-circular scroll cross-section (42) can be made gentle. When the change in curvature between the second arc portion (6) and the third arc portion (7) is gentle, it is possible to suppress the occurrence of pressure loss due to a sudden change in curvature between the second arc portion (6) and the third arc portion (7).
2) In some embodiments, in the scroll casing (3) described in 1), the near-circular scroll cross-section (42) satisfies a relationship of R1>R2, where R1 is a curvature radius of the first arc portion (5).
According to the above configuration 2), in the near-circular scroll cross-section (42), the curvature radius R1 of the first arc portion (5) is larger than the curvature radius R2 of the second arc portion (6). In this case, the change in curvature between the first arc portion (5) and the second arc portion (6) in the near-circular scroll cross-section (42) can be made gentle. As a result, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature from the first arc portion (5) and the second arc portion (6).
3) In some embodiments, in the scroll casing (3) described in 1), the near-circular scroll cross-section (42) satisfies a relationship of R2>R1, where R1 is a curvature radius of the first arc portion (5).
According to the above configuration 3), in the near-circular scroll cross-section (42), the curvature radius R1 of the first arc portion (5) is smaller than the curvature radius R2 of the second arc portion (6). In this case, the distance of the outermost end (second position P2) of the scroll passage (31) in the radial direction from the axis (CA) of the centrifugal compressor can be shortened. This makes it possible to downsize the scroll casing (30) and thus the centrifugal compressor (1). Further, a region (31A) of the scroll passage (31) facing the first arc portion (5) is a region where the flow from the diffuser passage (40) enters, and the swirling flow (SF) is formed on the downstream side (one-direction UD side) of the region (31A) in the scroll passage (31). Therefore, even when the curvature radius R1 of the first arc portion (5) is smaller than the curvature radius R2 of the second arc portion (6), by suppressing the occurrence of pressure loss on the downstream side of the region (31A), it is possible to sufficiently suppress the occurrence of pressure loss in the scroll passage (31).
4) In some embodiments, in the scroll casing (3) described in 3), the near-circular scroll cross-section (42) further includes a first straight portion (8) connecting the first arc portion (5) and the second arc portion (6).
When the distance of the outermost end (second position P2) of the scroll passage (31) in the radial direction from the axis (CA) of the centrifugal compressor (1) is shortened, it may be difficult to directly connect the first arc portion (5) and the second arc portion (6). According to the above configuration 4), with the first straight portion (8) connecting the first arc portion (5) and the second arc portion (6), the shape in which the first arc portion (5) and the second arc portion (6) are connected can be easily obtained.
5) In some embodiments, in the scroll casing (3) described in 2), the near-circular scroll cross-section (42) satisfies a relationship of R2/R1≥0.8 and R3/R2≥0.8.
According to the above configuration 5), the near-circular scroll cross-section (42) satisfies a relationship of R2/R1≥0.8. In other words, the curvature radius R2 of the second arc portion (6) has a curvature radius reduction ratio of 20% or less with respect to the curvature radius R1 of the first arc portion (5). When the curvature change amount between the first arc portion (5) and the second arc portion (6) is small, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature between the first arc portion (5) and the second arc portion (6). Further, the near-circular scroll cross-section (42) satisfies a relationship of R3/R2≥0.8. In other words, the curvature radius R3 of the third arc portion (7) has a curvature radius reduction ratio of 20% or less with respect to the curvature radius R2 of the second arc portion (6). When the curvature change amount between the second arc portion (6) and the third arc portion (7) is small, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature between the second arc portion (6) and the third arc portion (7).
6) In some embodiments, in the scroll casing (3) described in 4) or 3), the near-circular scroll cross-section (42) satisfies a relationship of R3/R2≥0.8.
According to the above configuration 6), the near-circular scroll cross-section (42) satisfies a relationship of R3/R2≥0.8. In other words, the curvature radius R3 of the third arc portion (7) has a curvature radius reduction ratio of 20% or less with respect to the curvature radius R2 of the second arc portion (6). When the curvature change amount between the second arc portion (6) and the third arc portion (7) is small, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature between the second arc portion (6) and the third arc portion (7).
7) In some embodiments, in the scroll casing (3) described in any one of 1) to 6), with respect to an angular position (θ) about a scroll center (O) of the scroll passage (31), when a joint position between a winding start (311) and a winding end (312) of the scroll passage (31) is defined as 60 degrees, and the angular position (θ) is defined such that the angle gradually increases from the joint position downstream in the scroll passage (31), the near-circular scroll cross-section (42) is formed in a range (S) where the angular position (θ) is from 120 degrees to 360 degrees.
The scroll passage (31) has a smaller scroll cross-sectional area as it is closer to the winding start (311). Therefore, it may be difficult to form the near-circular scroll cross-section (42) in the vicinity of the winding start. According to the above configuration 7), since the near-circular scroll cross-section (42) is formed in the range (S) where the angular position θ is from 120 degrees to 360 degrees, which is easy to form the near-circular scroll cross-section (42), the occurrence of pressure loss in the scroll passage (31) can be sufficiently suppressed.
8) In some embodiments, in the scroll casing (3) described in any one of 1) to 7), the third arc portion (7) is formed so as to include at least the third position (P3), the fourth position (P4), and the fifth position (P5).
According to the above configuration 8), since the third arc portion (7) includes the third position (P3), the fourth position (P4), and the fifth position (P5), the near-circular scroll cross-section (42) can have a gentle change in curvature in the range from the third position to the fifth position, which is important for determining the swirling state of the swirling flow (SF) formed in the scroll cross-section (42). Thus, it is possible to effectively suppress the occurrence of pressure loss due to a sudden change in curvature in the above-described range.
9) A centrifugal compressor (1) according to at least one embodiment of the present disclosure is provided with the scroll casing (3) described in any one of 1) to 8).
According to the above configuration 9), the occurrence of pressure loss in the scroll passage (31) can be suppressed, so that the efficiency of the centrifugal compressor (1) can be improved. In particular, the efficiency of the centrifugal compressor (1) can be effectively improved during the high flow rate operation.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/016871 | 4/17/2020 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2021/210164 | 10/21/2021 | WO | A |
| Number | Name | Date | Kind |
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| 9366265 | Tomita | Jun 2016 | B2 |
| 9541094 | Iwakiri | Jan 2017 | B2 |
| 9562541 | Iwakiri | Feb 2017 | B2 |
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| 10125787 | Rendel | Nov 2018 | B2 |
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| 20130272865 | Hoshi | Oct 2013 | A1 |
| 20130294903 | Tomita | Nov 2013 | A1 |
| 20130343885 | Iwakiri | Dec 2013 | A1 |
| 20150275915 | Rendel | Oct 2015 | A1 |
| 20180149170 | Iwakiri | May 2018 | A1 |
| 20180291922 | Iwakiri | Oct 2018 | A1 |
| 20180347382 | Iwakiri | Dec 2018 | A1 |
| 20190055959 | Iwakiri | Feb 2019 | A1 |
| 20210199125 | Teramoto | Jul 2021 | A1 |
| Number | Date | Country |
|---|---|---|
| 2005-2951 | Jan 2005 | JP |
| 2005002951 | Jan 2005 | JP |
| 6053993 | Dec 2018 | JP |
| WO 2017072899 | May 2017 | WO |
| WO 2018174186 | Sep 2018 | WO |
| Entry |
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| JP-2005002951-Translation from Espacenet (Year: 2005). |
| Japanese Notice of Reasons for Refusal for Japanese Application No. 2022-515165, dated Jul. 6, 2023, with English translation. |
| International Preliminary Report on Patentability and Written Opinion of the International Searching Authority for International Application No. PCT/JP2020/016871, dated Oct. 27, 2022. |
| International Search Report for International Application No. PCT/JP2020/016871, dated Jun. 16, 2020. |
| Number | Date | Country | |
|---|---|---|---|
| 20230049412 A1 | Feb 2023 | US |
