DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 11/21/2025 has been entered.
Response to Arguments
Applicant’s arguments, filed 11/21/2025, with respect to 112b rejection of Claims 19-20 have been fully considered and are persuasive. The 112b rejection of Claims 19-20 has been overcome.
Applicant’s arguments with respect to independent claim 1 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Shibata et al. (US 20200378389, hereinafter: “Shibata”) in view of Chiba et al. (JP H0914187, hereinafter: “Chiba”).
In reference to Claim 1
Shibata discloses:
A centrifugal compressor (1) comprising:
a casing (8, 14):
an impeller (4) housed in the casing; and
a shaft (6) coupled to the impeller,
the casing having a wall (wall of 14 facing impeller, Fig. 2-3) facing a back surface (16) of the impeller,
the shaft (6) being inserted into an insertion hole (hole show in Fig. 1-3) formed in the wall,
a back gap (“g”) being formed between the back surface of the impeller and the wall,
the back gap includes a first gap (gap between 16 and surface of 14 at the lower notch of surface 14; Fig. 17) corresponding to an inner peripheral side of the back surface of the impeller, the first gap extending in a direction perpendicular to an axis of the shaft so as to be parallel to the back surface of the impeller, the first gap forming a seal (6, 76) that seals between the back surface of the impeller and the wall [0126-0127],
the back gap includes a second gap (gap “g” at the outer radial end of the impeller; Fig. 17) corresponding to an outer peripheral side of the back surface of the impeller, and an axial width s (axial width of gap) of the second gap is greater than the axial width s of the first gap (as seen in both Fig. 17-18). and a ratio of the axial width s of the back gap to an impeller radius r satisfies a relationship of 0.008 s/r< 0.5, where the axial width s is a width of the back gap in an axial direction of the shaft, and the impeller radius r is a radius of the impeller [0031].
[0031, Shibata] In some embodiments, in the electric supercharger (8), a ratio G/R of a size G of a gap between the back surface of the compressor impeller and the back-surface side casing to an outer diameter R of the compressor impeller is less than 0.5%.
Although Shibata does not explicitly disclose the specific speed of the impeller is set to be less than 0.1, Shibata discloses the centrifugal impeller (4).
Chiba et al. (JP H0914187, hereinafter: “Chiba”), centrifugal impellers (centrifugal compressor “C”) have high efficiency (ƞ) at the low specific speed (ƞs) as shown in Figure 2 of Chiba. (“FIG. 2 shows the relationship between the specific speed n s of the compressor and the efficiency η. A is an axial flow compressor, B is a mixed flow compressor, and C is a centrifugal compressor. As shown in this figure, the axial compressor A has high efficiency in a region where the specific speed ns is relatively high (large flow rate, low pressure ratio), and the centrifugal compressor C has a specific speed ns”).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the impeller of Shibata by setting the impeller at low specific speed of less than 0.1 since centrifugal impellers are known in the art to be able to perform well at low specific speed as taught by Chiba, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
In reference to Claim 21
Shibata in view of Chiba discloses:
The centrifugal compressor of claim 1. Shibata discloses a recess (see recessed in the wall 14 in which part 76 is located) is formed on a surface of the wall facing the impeller and recessed into the wall away from the impeller, and the back surface of the impeller is located outside the recess.(Fig. 17-18).
Claims 4, 6, 7 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Shibata et al. (US 20200378389, hereinafter: “Shibata”) in view of Chiba et al. (JP H0914187, hereinafter: “Chiba”) as applied to claim 1 above, and further in view of Hasegawa et al. (US 20160061210, hereinafter: “Hasegawa”).
In reference to Claim 4
Shibata in view of Chiba discloses:
The centrifugal compressor of claim 1. Shibata discloses a radial bearing (10A, 10B) supporting the shaft at an outer periphery of the shaft [0065-0071] (Fig. 1, 15).
Shibata in view of Chiba is silent on the radial bearing is a foil bearing or a magnetic bearing.
Hasegawa teaches a centrifugal compressor comprising: a casing (6); an impeller (3, 4) housed in the casing; and a shaft (5) coupled to the impeller, the casing having a wall (16) facing a back surface (surface of impeller 3 and 4 facing wall 16 and 17 respectively in Fig. 2) of the impeller, the shaft being inserted into an insertion hole (inner bore of the casing 6 which includes wall 16) formed in the wall (“[0036] In addition, the first-stage impeller 3 and the second-stage impeller 4 are so-called open impellers such that shrouds 16 and 17 are separated from the impellers 3 and 4 and are provided on the casing 6 side.”), a back gap (“S” gap) being formed between the back surface of the impeller and the wall.
Hasegawa teaches a foil bearing or a magnetic bearing (7, 8) supporting the shaft at an outer periphery of the shaft (5) [0033].
Thus, based on the teaching of Hasegawa and Shibata in view of Chiba, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the bearing of Shibata in view of Chiba by utilizing a magnetic bearing as taught by Hasegawa for the purpose of utilizing a well-known bearing in a compressor.
In reference to Claims 6, and 17
Shibata in view of Chiba discloses:
The centrifugal compressor of claims 1, and 4. Shibata discloses a compressor impeller; however, Shibata is silent on the impeller pumping a refrigerant.
However, Hasegawa teaches the impeller pumps a refrigerant, and the refrigerant is an HFC refrigerant, an HFO refrigerant, a natural refrigerant, or a refrigerant mixture thereof [0032, Hasegawa].
Thus, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the compressor impeller of Shibata by utilizing it to pump a refrigerant as claimed as taught by Hasegawa for the purpose of utilizing a well-known usage of a compressor impeller.
In reference to Claim 7
Shibata in view of Chiba discloses:
The centrifugal compressor of claim 1. Shibata discloses a compressor impeller; however, Shibata is silent on the impeller pumping a refrigerant and used in a refrigeration apparatus.
Hasegawa teaches a refrigeration apparatus comprising: a refrigerant circuit configured to perform a refrigeration cycle, the refrigerant circuit including the centrifugal compressor of claim 1 [0032].
Thus, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the compressor impeller of Shibata by utilizing it to pump a refrigerant as claimed as taught by Hasegawa for the purpose of utilizing a well-known usage of a compressor impeller.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Shibata et al. (US 20200378389, hereinafter: “Shibata”) in view of Chiba et al. (JP H0914187, hereinafter: “Chiba”) as applied to claim 1 above, and further in view of Ozasa (US 20190207448).
In reference to Claim 5
Shibata in view of Chiba discloses:
The centrifugal compressor of claim 1. Although Shibata in view of Chiba discloses the rotor shaft (6, Shibata) having a rotation speed, Shibata in view of Chiba is silent on a maximum number of rotations of the shaft is 30000 rpm or more.
Ozasa teaches a compressor (3) having rotor shaft speed a high-speed rotation of 100000-200000 rpm [0037].
Thus, based on the teaching of Ozasa and Shibata in view of Chiba, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the rotor shaft speed Shibata in view of Chiba by constructing it to reach high speeds over 30000 rpm as claimed as taught by Ozasa for the purpose of utilizing a well-known speed limit of a compressor.
Claim 12 are rejected under 35 U.S.C. 103 as being unpatentable over Shibata et al. (US 20200378389, hereinafter: “Shibata”) in view of Chiba et al. (JP H0914187, hereinafter: “Chiba”) and Hasegawa et al. (US 20160061210, hereinafter: “Hasegawa”) as applied to claim 1 above, and further in view of Ozasa (US 20190207448).
In reference to Claims 12
Shibata in view of Chiba and Hasegawa discloses:
The centrifugal compressor of claim 4. Although Shibata in view of Chiba discloses the rotor shaft (6, Shibata) having a rotation speed, Shibata in view of Chiba is silent on a maximum number of rotations of the shaft is 30000 rpm or more.
Ozasa teaches a compressor (3) having rotor shaft speed a high-speed rotation of 100000-200000 rpm [0037].
Thus, based on the teaching of Ozasa and Shibata in view of Chiba and Hasegawa, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the rotor shaft speed Shibata in view of Chiba and Hasegawa by constructing it to reach high speeds over 30000 rpm as claimed as taught by Ozasa for the purpose of utilizing a well-known speed limit of a compressor.
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Shibata et al. (US 20200378389, hereinafter: “Shibata”) in view of Chiba et al. (JP H0914187, hereinafter: “Chiba”) and Ozasa (US 20190207448) as applied to claim 1 above, and further in view Hasegawa et al. (US 20160061210, hereinafter: “Hasegawa”).
In reference to Claim 18
Shibata in view of Chiba and Ozasa discloses:
The centrifugal compressor of claim 5. Shibata discloses a compressor impeller; however, Shibata is silent on the impeller pumping a refrigerant.
However, Hasegawa teaches the impeller pumps a refrigerant, and the refrigerant is an HFC refrigerant, an HFO refrigerant, a natural refrigerant, or a refrigerant mixture thereof [0032, Hasegawa].
Thus, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the compressor impeller of Shibata by utilizing it to pump a refrigerant as claimed as taught by Hasegawa for the purpose of utilizing a well-known usage of a compressor impeller.
Claim 22 is rejected under 35 U.S.C. 103 as being unpatentable over Shibata et al. (US 20200378389, hereinafter: “Shibata”) in view of Chiba et al. (JP H0914187, hereinafter: “Chiba”) as applied to claim 1 above, and further in view of Suematsu et al. (JP 2020197133, hereinafter: “Suematsu”).
In reference to Claim 22
Shibata in view of Chiba discloses:
The centrifugal compressor of claim 1. Although Shibata discloses a recess portion 82 may be formed on the back surface (16) of the impeller (4) and Shibata discloses the back surface of the impeller is flat in other embodiments disclosed.
Suematsu teaches a compressor impeller (41) discloses the back surface (41A) of the impeller is flat and the wall (3A) of the casing facing the back of the impeller includes a notch that is recessed into the wall away from the impeller (Fig. 2).
Thus, based on the teaching of Suematsu and Shibata in view of Chiba, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to modify the back surface of the impeller of Shibata in view of Chiba by constructing the back surface of the impeller is flat while maintaining a notch/recess in the wall of the casing which faces the back surface of the impeller as taught by Suematsu for the purpose of providing a well-known gap configuration in a compressor impeller assembly.
Conclusion
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/AYE S HTAY/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745