Prosecution Insights
Last updated: April 19, 2026
Application No. 19/106,868

CENTRIFUGAL FLUID MACHINE AND SINGLE-SHAFT MULTI-STAGE CENTRIFUGAL COMPRESSOR

Non-Final OA §112
Filed
Feb 26, 2025
Examiner
WONG, ELTON K
Art Unit
3745
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Hitachi Industrial Products Ltd.
OA Round
1 (Non-Final)
78%
Grant Probability
Favorable
1-2
OA Rounds
2y 5m
To Grant
97%
With Interview

Examiner Intelligence

Grants 78% — above average
78%
Career Allow Rate
356 granted / 458 resolved
+7.7% vs TC avg
Strong +19% interview lift
Without
With
+19.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 5m
Avg Prosecution
32 currently pending
Career history
490
Total Applications
across all art units

Statute-Specific Performance

§101
0.4%
-39.6% vs TC avg
§103
42.7%
+2.7% vs TC avg
§102
16.9%
-23.1% vs TC avg
§112
36.1%
-3.9% vs TC avg
Black line = Tech Center average estimate • Based on career data from 458 resolved cases

Office Action

§112
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 . Claims 1-15 are currently pending. Claims 1-15 are rejected. Specification The disclosure is objected to because of the following informalities: Paragraph [0074] recites “interna flow”. This is believed to be a typographical error. Appropriate correction is required. Claim Interpretation The following is a quotation of 35 U.S.C. 112(f): (f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked. As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph: (A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function; (B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and (C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function. Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function. Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function. Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are: Claim 1, Lines 26-27, “inflow control device” modified by the function of being configured such that it “controls an inflow of the working fluid introduced into a compressor from each of the first intake nozzle and the second intake nozzle”. Claim 2, Lines 25-26, “inflow control device” modified by the function of being configured such that it “controls an inflow of the working fluid introduced from each of the first intake nozzle and the second intake nozzle into the compressor”. Claim 8, Lines 30-31, “inflow control device” modified by the function of being configured such that it “controls an inflow of the working fluid introduced from each intake nozzle into the compressor”. In all instances, the “inflow control device” is interpreted to be an on-off valve, flow rate control valve, or equivalents thereof as exemplified in paragraph [0042] of the Specification filed February 26, 2025. Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof. If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. Claim Rejections - 35 USC § 112(b) The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. Claims 1-15 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Regarding Claims 1-2 and 8, Lines 18-19 of Claim 1, Lines 17-18 of Claim 2, and Lines 17-18 of Claim 8 recite “the side opposite to the first intake nozzle”. It is unclear where this positioning would be. The claims do not provide a frame of reference, nor what is considered the “side” in the missing frame of reference. As such, it is unclear what would be considered “opposite”. Regarding Claims 3 and 9, Line 3 of Claim 3 and Line 3 of Claim 9 recite “vicinity of installation locations”. The term “vicinity” is a relative term which renders the claims indefinite. The term “vicinity” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The claims do not define what region is encompassed by “vicinity” and what is not. In other words, how close to the installation locations is considered the “vicinity”? Regarding Claim 15, Line 4 recites “or the like”. The phrase "or the like" renders the claim indefinite because the claim includes elements not actually disclosed (those encompassed by "or the like"), thereby rendering the scope of the claim unascertainable. See MPEP § 2173.05(d). Claims 4-7, 10-14 are subsequently rejected for their dependencies upon a previously rejected claim. Allowable Subject Matter Claims 1-15, as far as they are definite and understood, would be allowable if rewritten or amended to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action. Regarding Claim 1, interpreting “inflow control device” under 35 U.S.C. 112(f) to be an on-off valve, flow rate control valve, or equivalents thereof as exemplified in paragraph [0042] of the Specification, Figures 1-3 of Nakinawa et al. (US 2017/370377 A1), hereinafter Nakinawa, teach a centrifugal fluid machine comprising: a rotary shaft (2); a centrifugal impeller (3a) attached to the rotary shaft (2); a bearing (13b) supporting the rotary shaft (2); and a casing (10) accommodating the rotary shaft (2), the centrifugal impeller (3a), and the bearing (13b), wherein the centrifugal fluid machine includes an intake flow path (follow G) which is provided in the casing (10) on the upstream side (left side in Figure 1) of the centrifugal impeller (3a) and introduces a working fluid (G) from a radial direction (outwards from O) of the rotary shaft (2) to cause the working fluid (G) to flow into the centrifugal impeller (3a), the intake flow path includes: a first intake nozzle (21) introducing the working fluid (G); an annular flow path part (B1) provided around the rotary shaft (2) and connected to the first intake nozzle (21); an L-shaped bend part (see between 41 and FC along the path of G in Figure 1) which is provided between the annular flow path part (B1) and an inlet (left end of 3a in Figure 1) of the centrifugal impeller (3a) and redirects a flow of the working fluid (G) in an axial direction (horizontal direction in Figure 1) of the rotary shaft (2); a second intake nozzle (22) provided in the casing (10) on the side opposite to the first intake nozzle (21) and connected to the annular flow path part (B1); and a rotation prevention plate (41 or 42) provided on the side opposite to the first intake nozzle (21) in the annular flow path part (B1), the first intake nozzle (21) is arranged toward a direction of the rotary shaft (2) [0026-0031, 0040-0041, 0056-0057] Nakinawa does not expressly teach the second intake nozzle is arranged in a direction deviated from the direction of the rotary shaft, and the first intake nozzle and the second intake nozzle are each equipped with an inflow control device which controls an inflow of the working fluid introduced into a compressor from each of the first intake nozzle and the second intake nozzle. Rather, both nozzles (21, 22) are arranged along the direction coinciding with L in Figures 2-3. Paragraphs [0055-0061] of the Specification for the instant application explain the purpose of the claimed structure. The inflow control devices allow for the control of flow rates to be adjusted between the first and second intake nozzles. By doing so, a degree of pre-rotation to the flow of the working fluid is adjusted. This allows expansion of the operation range and improving the uniformity of the circumferential distribution of flow. Thus, the difference in structure provides a unique function to the claimed invention that is not contemplated by the art of record. Claim 1 is considered allowable in view of Nakinawa. Claims 2 and 8 contain allowable subject matter of sufficiently similar scope to Claim 1. Therefore, Claims 2 and 8 are considered allowable for the same reasons set forth above. Claims 3-7, 9-15 subsequently depend upon Claims 2 and 8, respectively. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: Nakinawa et al. (US 2016/0327056 A1) exemplify the state of the art of multistage compressors. Nakinawa et al. (US 2017/0254344 A1) exemplify the state of the art of rectification plates. Any inquiry concerning this communication or earlier communications from the examiner should be directed to ELTON K WONG whose telephone number is (408)918-7626. The examiner can normally be reached Mon-Fri 8:00AM - 5:00PM PST. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Court Heinle can be reached at (571)270-3508. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /ELTON K WONG/Primary Examiner, Art Unit 3745
Read full office action

Prosecution Timeline

Feb 26, 2025
Application Filed
Feb 07, 2026
Non-Final Rejection — §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12600461
COVERING SYSTEM AND METHOD FOR A PITCH LINK OF A HELICOPTER
2y 5m to grant Granted Apr 14, 2026
Patent 12601282
TURBOFAN GAS TURBINE ENGINE WITH INNER RING REINFORCING STRUCTURE AND METHODS OF PRODUCING THE SAME
2y 5m to grant Granted Apr 14, 2026
Patent 12595823
AIRCRAFT ENGINE WITH SQUEEZE FILM DAMPER
2y 5m to grant Granted Apr 07, 2026
Patent 12595743
BLADED TURBOMACHINE ASSEMBLY INCLUDING MEANS FOR LIMITING VIBRATIONS BETWEEN PLATFORMS
2y 5m to grant Granted Apr 07, 2026
Patent 12560096
STATOR PART HAVING A FIN, IN A TURBINE ENGINE
2y 5m to grant Granted Feb 24, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

1-2
Expected OA Rounds
78%
Grant Probability
97%
With Interview (+19.3%)
2y 5m
Median Time to Grant
Low
PTA Risk
Based on 458 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month