Office Action Predictor
Last updated: April 15, 2026
Application No. 18/509,626

DUAL PHASE DIFFERENCE PUMP

Non-Final OA §103§112
Filed
Nov 15, 2023
Examiner
OMGBA, ESSAMA
Art Unit
3746
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Shimadzu Corporation
OA Round
2 (Non-Final)
59%
Grant Probability
Moderate
2-3
OA Rounds
3y 6m
To Grant
88%
With Interview

Examiner Intelligence

Grants 59% of resolved cases
59%
Career Allow Rate
478 granted / 806 resolved
-10.7% vs TC avg
Strong +29% interview lift
Without
With
+28.8%
Interview Lift
resolved cases with interview
Typical timeline
3y 6m
Avg Prosecution
20 currently pending
Career history
826
Total Applications
across all art units

Statute-Specific Performance

§101
0.2%
-39.8% vs TC avg
§103
57.3%
+17.3% vs TC avg
§102
22.2%
-17.8% vs TC avg
§112
17.3%
-22.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 806 resolved cases

Office Action

§103 §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 . Allowable Subject Matter The indicated allowability of claims 4 and 8 is withdrawn in view of the new interpretation applied to the previous reference(s) to Kitano et al. Rejections based on the new interpretation of the reference(s) follow. Claim Rejections - 35 USC § 112 The following is a quotation of 35 U.S.C. 112(d): (d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers. The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph: Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers. Claim 7 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends. Claim 7 fails to further limit claim 1 because a coupler that includes a coupling member 116 splines) provided between the shafts, the coupling member coupling the shafts has been recited in claim 1. Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements. 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. Claim(s) 1 and 4-8 are is/are rejected under 35 U.S.C. 103 as being unpatentable over Kitano et al. (JP04303190) in view of Applicant’s Admitted Prior Art (AAPA). With regards to claim 1, Kitano et al. discloses a dual phase difference pump (fig. 7), the dual phase difference pump comprising two gear pump units in series, the two gear pumps each including a pair of gears being configured to mesh with each other (109, 111 and 113, 115), and a shaft, the shafts of the two gear pump units (108, 111) being coupled to each other using a coupler 116, the coupler including a spline coupling structure including a male spline 108 and a female spline 112a, the male spline fitted to the female spline, the male spline being provided at one shaft, the female spline being provided at another shaft, the one shaft and the other shaft being coupled to each other (fig. 7), wherein the spline coupling has a first number of teeth m, each of the pair of gears includes a gear portion, wherein each of the pair of gears has a second number of teeth n, wherein m is a divider of n (since the number of teeth of the spline is equal to the number of teeth of the gears, see paragraph [0003] of the provided English translation). Although Kitano et al. does not explicitly disclose the pair of gears meshing with each other without backlash however, it is known to design pairs of gears such that they mesh without backlash in order to reduce pressure pulsation as attested by AAPA, see paragraphs [0005] and [0006]. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have design the pair of gears of Kitano et al. so that they mesh without backlash, in light of the teachings of AAPA, in order to reduce pressure pulsation. Regarding the recitation “the coupler is configured to couple the shaft to each other at any of a plurality of predetermined phase angles, wherein the coupler is configured to couple the shafts to each other in the plurality of predetermined phase angles only in configuration wherein a phase difference between the two gear pump units is equal, irrespective of which predetermined phase angle is selected among the plurality of predetermined phase angles as a phase angle at which the shafts are coupled together”, Applicant should note that because the coupler of Kitano et al. is structurally the same as Applicant’s coupler, it is expected to have the same capabilities and functions. Further, Applicant should note that the dual phase differential pump of Kitano et al./AAPA is capable of being used to reduce pressure pulsation during operation of the dual phase difference pump because Kitano et al./AAPA render obvious the claimed pump. As it has been held, “a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim. With regards to claim 4, Kitano et al. discloses a dual phase difference pump (fig. 7), the dual phase difference pump comprising two gear pump units in series, the two gear pumps each including a pair of gears being configured to mesh with each other (109, 111 and 113, 115), and a shaft, the shafts of the two gear pump units (108, 111) being coupled to each other using a coupler 116, the coupler including a spline coupling structure including a male spline 108 and a female spline 112a, the male spline fitted to the female spline, the male spline being provided at one shaft, the female spline being provided at another shaft, the one shaft and the other shaft being coupled to each other (fig. 7), a gear of the pair of gears including the female spline has a wall thickness being equal at each bottom land, see figure 9. Although Kitano et al. does not explicitly disclose the pair of gears meshing with each other without backlash however, it is known to design pairs of gears such that they mesh without backlash in order to reduce pressure pulsation as attested by AAPA, see paragraphs [0005] and [0006]. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have design the pair of gears of Kitano et al. so that they mesh without backlash, in light of the teachings of AAPA, in order to reduce pressure pulsation. Regarding the recitation ‘the coupler is configured to couple the shaft to each other at any of a plurality of predetermined phase angles, wherein the coupler is configured to couple the shafts to each other in the plurality of predetermined phase angles only in configuration wherein a phase difference between the two gear pump units is equal, irrespective of which predetermined phase angle is selected among the plurality of predetermined phase angles as a phase angle at which the shafts are coupled together”, Applicant should note that because the coupler of Kitano et al. is structurally the same as Applicant’s coupler, it is expected to have the same capabilities and functions. Regarding claim 5, Applicant should note that because Kitano et al./AAPA discloses the number of teeth of the spline being equal to the number of teeth of the gears, it ensues that a number of tooth spaces of the female spline will also be equal to the number of teeth of the gear and will provide for the tooth spaces of the female spline and the teeth of the gear to be identical in angle to each other. Regarding claim 6, see coupler 116 in figure 7. Regarding claim 7, see coupler 116 in figure 7. Regarding claim 8, Kitano et al. discloses a dual phase difference pump (fig. 7), the dual phase difference pump comprising two gear pump units in series, the two gear pumps each including a pair of gears being configured to mesh with each other (109, 111 and 113, 115), and a shaft, the shafts of the two gear pump units (108, 111) being coupled to each other using a coupler 116,. Although Kitano et al. does not explicitly disclose the pair of gears meshing with each other without backlash however, it is known to design pairs of gears such that they mesh without backlash in order to reduce pressure pulsation as attested by AAPA, see paragraphs [0005] and [0006]. Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have design the pair of gears of Kitano et al. so that they mesh without backlash, in light of the teachings of AAPA, in order to reduce pressure pulsation. Regarding the recitation ‘the coupler is configured to couple the shaft to each other at any of a plurality of predetermined phase angles, wherein the coupler is configured to make a phase difference between the two gear pump units equal, irrespective of which predetermined phase angle is selected among the plurality of predetermined phase angles as a phase angle at which the shafts are coupled to each other”, Applicant should note that because the coupler of Kitano et al. is structurally the same as Applicant’s coupler, it is expected to have the same capabilities and functions. Further, because the coupler is configured to make a phase difference between the two gear pump units equal, irrespective of which predetermined phase angle is selected among the plurality of predetermined phase angles as a phase angle at which the shafts are coupled to each other, choosing a phase difference between the two gear pump units to be set to ¼ of a tooth-to-tooth angle of a gear of the pair of angles, one of ordinary skill in the art would understand that the particular phase difference is of no significance since the dual phase difference pump will perform well at any of the phase angles. Allowable Subject Matter Claim 3 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. Response to Arguments Applicant’s arguments related to interpreting the claims as invoking 112(f) or 112, sixth paragraph have been fully considered and are persuasive. Therefore the interpretation has been withdrawn. Applicant’s arguments with respect to claim(s) 1 and 4-8 have been considered but are moot because the new ground of rejection does not rely on the interpretation of the reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Any inquiry concerning this communication or earlier communications from the examiner should be directed to ESSAMA OMGBA whose telephone number is (469)295-9278. The examiner can normally be reached Monday to Thursday: 8:00 AM – 6:00 PM. 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, Alexander Beck can be reached at 571-272-3750. 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. /ESSAMA OMGBA/Supervisory Patent Examiner, Art Unit 3746
Read full office action

Prosecution Timeline

Nov 15, 2023
Application Filed
Feb 22, 2025
Non-Final Rejection — §103, §112
May 06, 2025
Examiner Interview Summary
May 06, 2025
Applicant Interview (Telephonic)
May 22, 2025
Response Filed
Jan 02, 2026
Non-Final Rejection — §103, §112
Feb 23, 2026
Examiner Interview Summary
Feb 23, 2026
Applicant Interview (Telephonic)
Apr 01, 2026
Response Filed

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

2-3
Expected OA Rounds
59%
Grant Probability
88%
With Interview (+28.8%)
3y 6m
Median Time to Grant
Moderate
PTA Risk
Based on 806 resolved cases by this examiner. Grant probability derived from career allow rate.

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