Prosecution Insights
Last updated: April 19, 2026
Application No. 18/841,655

FLUID PRESSURE CIRCUIT

Final Rejection §102§103
Filed
Aug 26, 2024
Examiner
NGUYEN, DUSTIN T
Art Unit
3745
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Eagle Industry Co. Ltd.
OA Round
4 (Final)
72%
Grant Probability
Favorable
5-6
OA Rounds
2y 7m
To Grant
90%
With Interview

Examiner Intelligence

Grants 72% — above average
72%
Career Allow Rate
332 granted / 460 resolved
+2.2% vs TC avg
Strong +18% interview lift
Without
With
+18.0%
Interview Lift
resolved cases with interview
Typical timeline
2y 7m
Avg Prosecution
33 currently pending
Career history
493
Total Applications
across all art units

Statute-Specific Performance

§101
0.9%
-39.1% vs TC avg
§103
37.8%
-2.2% vs TC avg
§102
26.1%
-13.9% vs TC avg
§112
32.7%
-7.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 460 resolved cases

Office Action

§102 §103
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 . Response to Arguments Applicant’s arguments, see remarks, filed 12/22/2025, with respect to the rejection(s) of claim(s) 1-10 under U.S.C. 112(a) and the objections of the office action dated 10/07/2025 have been fully considered and are persuasive, applicant’s amendments to the claims remedies the rejections and objections. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of new reference Kang (US 10988915). Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claim(s) 1-4, 6-9 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kang (US 10988915). Kang discloses: 1. (currently amended) A fluid pressure circuit, comprising: a fluid supply source (310); a cylinder device (200) including a first chamber (201) and a second chamber (202) which are partitioned from each other; a tank (tank symbol seen in Fig. 1, downstream 370); a flow diverter valve (400); and a controller (700), wherein the flow diverter valve is disposed on a flow passage disposed between the fluid supply source and the cylinder device (flow passage that includes 770 is between the fluid supply source 310 and the cylinder device 200), the flow passage is configured to communicate with a recovery passage (675) through which the return fluid flows from the first chamber to the second chamber (Col. 5 lines 61-67, Col. 6 lines 1-5), and the flow diverter valve is valve configured to receive an electrical control signal from the controller (Col. 6 lines 32-67, electric signal lines between controller 700 and valve 400 to spools 410 and 420 that form throttles), to divert some of a return fluid from the cylinder device and to discharge the some of the return fluid to the tank via a throttle (Col. 5 lines 54-67, Col. 6 lines 1-5, lines 32-67). 2. (previously presented) The fluid pressure circuit according to claim 1, wherein the fluid pressure circuit further includes a throttle passage provided with the throttle in the flow diverter valve (throttle passage is formed within 410), and a low-fluid-resistance passage with a lower fluid resistance than the throttle passage, wherein the low-fluid-resistance passage is configured for communicating with the recovery passage (throttle within recovery passage is adjustable to be relatively lower fluid resistance, Col. 6 lines 20-26, lines 38-53, therefore at least when the opening area of the spool 420 is increased is interpreted to be a low-fluid-resistance passage). 3. (previously presented) The fluid pressure circuit according to claim 2, wherein the low-fluid-resistance passage is provided in the flow diverter valve (low-fluid resistance passage through 420 is within the flow diverter valve 400). 4. (previously presented) The fluid pressure circuit according to claim 2, wherein the throttle passage includes two passage parts, wherein one of the two passage parts is configured for communicating with the recovery passage (passage path 420 communicates with the recovery passage 675). 6. (previously presented) The fluid pressure circuit according claim 1, wherein the recovery passage is configured to allow for a flow therein only when the cylinder device is retracted (Col. 8 lines 22-26 discloses that controller controls the flow diverter valve spool 420, which controls the opening amount of the recovery passage 675, is closed when the cylinder device is ascending/extending and Col. 5 lines 61-67, Col. 6 lines 1-5, Col. 7 lines 1-9 discloses the controller controls the flow diverter valve spool 420 to be open, which opens the recovery passage 675, when the cylinder device is retracting/descending). 7. (previously presented) The fluid pressure circuit according to claim 2, wherein the recovery passage is configured to allow for a flow therein only when the cylinder device is retracted (Col. 8 lines 22-26 discloses that controller controls the flow diverter valve spool 420, which controls the opening of the recovery passage, is closed when the cylinder device is ascending/extending and Col. 5 lines 61-67, Col. 6 lines 1-5, Col. 7 lines 1-9 discloses the controller controls the flow diverter valve spool 420 to be open, which opens the recovery passage 675, when the cylinder device is retracting/descending). 8. (previously presented) The fluid pressure circuit according to claim 3, wherein the recovery passage is configured to allow for a flow therein only when the cylinder device is retracted (Col. 8 lines 22-26 discloses that controller controls the flow diverter valve spool 420, which controls the opening of the recovery passage, is closed when the cylinder device is ascending/extending and Col. 5 lines 61-67, Col. 6 lines 1-5, Col. 7 lines 1-9 discloses the controller controls the flow diverter valve spool 420 to be open, which opens the recovery passage 675, when the cylinder device is retracting/descending). 9. (previously presented) The fluid pressure circuit according to claim 4, wherein the recovery passage is configured to allow for a flow therein only when the cylinder device is retracted (Col. 8 lines 22-26 discloses that controller controls the flow diverter valve spool 420, which controls the opening of the recovery passage, is closed when the cylinder device is ascending/extending and Col. 5 lines 61-67, Col. 6 lines 1-5, Col. 7 lines 1-9 discloses the controller controls the flow diverter valve spool 420 to be open, which opens the recovery passage 675, when the cylinder device is retracting/descending). 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) 5 and 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kang in view of Shirai et al. (US 5218897), hereinafter ‘Shirai’. Regarding claim 5, Kang discloses the fluid pressure circuit according to claim 1, further comprising a switching valve (500) provided in a flow passage between the fluid supply source (310) and the flow diverter valve (400) to control an inflow and outflow of a fluid between the fluid supply source and the cylinder device (Col. 5 lines 18-22), Kang does not disclose wherein the recovery passage is provided inside the switching valve. However, Shirai discloses a fluid pressure circuit similar to Kawasaki and the present application and therefore constitutes analogous art. Shirai teaches a switching valve 10 provided in between the pressure source 23 and the boom cylinder 32 to control an inflow and outflow of a fluid between the fluid supply source and the cylinder device, and the recovery passage 26 is provided inside the switching valve, wherein the recovery passage 26 allows fluid from the piston side chamber 3a to flow to the rod side chamber 3b similar to the recovery passage of the present application and Kang’s recovery passage (Kang, recovery passage 675 corresponds to Shirai’s recovery passage 26). Since combining prior at elements according to known methods to yield predictable results is an exemplary rationale the supports a conclusion of obviousness, and since rearrangement of parts provides supporting rationale, it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have modified the system of Kang to have provided the recovery passage within the switching valve as taught by Shirai. The proposed modification would not yield any unexpected results and would not change the primary operation of the system of Kang. Repositioning the recovery passage to within another valve appears to be a matter of design choice because relocating the conduit to extend through the valve would not change the function of the recovery passage and would not change the function of the system. The combination of Kang and Shirai further renders obvious: 10. (previously presented) The fluid pressure circuit according to claim 5, wherein the recovery passage is configured to allow for a flow therein only when the cylinder device is retracted (Kang, Col. 8 lines 22-26 discloses that controller controls the flow diverter valve spool 420, which controls the opening of the recovery passage, is closed when the cylinder device is ascending/extending and Col. 5 lines 61-67, Col. 6 lines 1-5, Col. 7 lines 1-9 discloses the controller controls the flow diverter valve spool 420 to be open, which opens the recovery passage 675, when the cylinder device is retracting/descending). Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Zhang et al. (US 9279236) discloses a pertinent fluid system with a recovery passage and a solenoid actuated valve 74 that directs fluid to a tank 52 that is located on a branching conduit of the recovery passage Shimada (US 10801533) discloses pertinent fluid system a solenoid controlled diverter valve with throttles Kawasaki et al. (US 9200430) discloses a pertinent fluid system that could be modified to have solenoid controlled diverter valve Egawa et al. (US 2018/0119388) discloses a pertinent fluid system including a recovery passage, and a diverter valve 26, that can be used to teach a recovery passage or be modified to have the diverter valve to be solenoid actuated Egawa et al. (US 2017/0314233) discloses a pertinent fluid system including a solenoid actuated diverter valve that could be modified with a recovery passage Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a). A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action. Any inquiry concerning this communication or earlier communications from the examiner should be directed to Dustin T Nguyen whose telephone number is (571)270-0163. The examiner can normally be reached M - F: 8:00am - 4:30pm. 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, Nathaniel E. Wiehe can be reached at (571) 272-8648. 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. /DUSTIN T NGUYEN/ Primary Examiner, Art Unit 3745 January 12, 2026
Read full office action

Prosecution Timeline

Aug 26, 2024
Application Filed
Aug 26, 2024
Response after Non-Final Action
Apr 08, 2025
Non-Final Rejection — §102, §103
Jun 13, 2025
Response Filed
Jun 26, 2025
Final Rejection — §102, §103
Sep 30, 2025
Request for Continued Examination
Oct 02, 2025
Response after Non-Final Action
Oct 06, 2025
Non-Final Rejection — §102, §103
Dec 22, 2025
Response Filed
Jan 12, 2026
Final Rejection — §102, §103
Mar 19, 2026
Request for Continued Examination
Apr 07, 2026
Response after Non-Final Action

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12600482
ACTUATOR, SAFETY DEVICE, AND FLYING BODY
2y 5m to grant Granted Apr 14, 2026
Patent 12601152
A MACHINE COMPRISING A SWING-TRAVEL HYDRAULIC SYSTEM
2y 5m to grant Granted Apr 14, 2026
Patent 12589489
PRESSURIZED SLEEVE FOR ROUTING OF LINEAR COMPONENTS
2y 5m to grant Granted Mar 31, 2026
Patent 12560185
WORKING CYLINDER, IN PARTICULAR A HYDRAULIC WORKING CYLINDER
2y 5m to grant Granted Feb 24, 2026
Patent 12546296
CYLINDER IN PARTICULAR FOR HYDROGEN TANK CYCLING FACILITY
2y 5m to grant Granted Feb 10, 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

5-6
Expected OA Rounds
72%
Grant Probability
90%
With Interview (+18.0%)
2y 7m
Median Time to Grant
High
PTA Risk
Based on 460 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