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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 03/19/2026 has been entered.
Response to Arguments
Applicant's arguments filed 03/19/2026 have been fully considered but they are not persuasive.
Applicant's remarks state that:
Turning to the art rejections and considering first the rejection of claims 1-4 and 6-9 as anticipated by Kang, Kang discloses a fluid pressure circuit including a fluid supply source (310), a cylinder device (200) provided with a first chamber (2019 and a second chamber (202), a tank (tank symbol), a flow diverter valve 400, and a controller (700). On page 3 of the Action, the Examiner suggests that in Col. 5 lines 54-67 and Col. 6 lines 1-5 of Kang that the flow diverter valve 400 might be a valve configured to receive an electrical control signal from the controller, to divert some of the return fluid from the cylinder device and to discharge the some of the return fluid to the tank via a throttle. This means Kang teaches that the return fluid to be returned the cylinder device and the return fluid to be diverted and discharged to the tank pass through the same throttle. Therefore, Kang fails to teach or suggest the aforementioned important features of the present invention recited in amended independent claim 1, especially that "the flow diverter valve is a valve which is configured to receive an electrical control signal from the controller, to divert some of the return fluid from the cylinder device and to discharge the some of the return fluid to the tank via a throttle, and in which the return fluid to be returned to the second chamber does not pass through the throttle". Thus, claim 1 and claims 2-4 and 6-9 which depend directly or indirectly thereon cannot be said to be anticipated by or obvious from Kang.
However, Kang does not appear to support applicant’s assertion of "this means Kang teaches that the return fluid to be returned the cylinder device and the return fluid to be diverted and discharged to the tank pass through the same throttle." Kang’s drawings appear to show two distinct throttles formed by 410 and 420. The fluid returning from the hydraulic cylinder 200 is split between the two distinct throttles 410 and 420. Kang Col. 6 lines 20-67 discloses controlling both the openings of spools 410 and 420 to adjust the throttle sizes to adjust flow rates through each of them respectively. The return fluid from the hydraulic cylinder is split such that some fluid returns to the tank via throttle formed by 410 and some fluid flows through a throttle formed by 420 which is distinct from throttle 410, and therefore meets the limitation "an in which the return fluid to be returned to the second chamber does not pass through the throttle", wherein in "the throttle" refers to the throttle established in this limitation "that diverts some of the return fluid from the cylinder device and to discharge the some of the return fluid to the tank via a throttle".
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 a 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 the 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);
and in which the return fluid to be returned to the second chamber does not pass through the throttle (Kang’s drawings appear to show two distinct throttles formed by 410 and 420. The fluid returning from the hydraulic cylinder 200 is split between the two distinct throttles 410 and 420. Kang Col. 6 lines 20-67 discloses controlling both the openings of spools 410 and 420 to adjust the throttle sizes to adjust flow rates through each of them respectively. The return fluid from the hydraulic cylinder is split such that some fluid returns to the tank via throttle formed by 410 and some fluid flows through a throttle formed by 420 which is distinct from throttle 410, and therefore meets the limitation "an in which the return fluid to be returned to the second chamber does not pass through the throttle", wherein in "the throttle" refers to the throttle established in this limitation "that diverts some of the return fluid from the cylinder device and to discharge the some of the return fluid to the tank via a throttle").
2. (previously presented) The fluid pressure circuit according to claim 1, wherein the fluid pressure circuit further includes a throttle passage provided separately from the throttle of 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
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.
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/DUSTIN T NGUYEN/ Primary Examiner, Art Unit 3745 April 24, 2026
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