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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 05/08/2026, 06/03/2026 has been entered.
Response to Arguments
Applicant’s arguments, see remarks, filed 05/08/2026, with respect to the drawing objections and the rejection(s) of claim(s) under U.S.C. 112(b) have been fully considered and are persuasive, applicant’s amendments to the claims remedies the clarity issues. Therefore, these objections and rejections have been withdrawn.
Applicant's arguments filed 05/08/2026 pertaining to the U.S.C. 103 rejections have been fully considered but they are not persuasive.
Applicant’s remarks state that Noble does not disclose nor render obvious the limitation of:
delay commanding:
a. the fluid switching valve to the second actuating position,
b. the bypass valve to the bypass position, or
c. the hydraulic pump to stop pressurizing the hydraulic fluid,
However, Noble Col. 15 line 32-37 states that at time t3 the controller actuates the flow switching device, and states at t2 is when the shuttle valve 124 is opened due to the stem contacted an end of the housing. There is a time between t2 and t3 after the pressure has dropped and has been detected by the pressure sensor, and before the control signal is sent to the switching valve which is indicated by the small horizontal line between t2 and t3, which is a delay in sending the control signal to the flow control valve.
Furthermore, Noble, claim 14 also recites “wherein said controller adds a predetermined delay to the timing for sending said electronic signal to said flow switching device so that said piston is stationary for at least a predetermined time between each piston stroke" which indicates a delay exists after determining that the piston is at the end of its stroke and before the control signal to the fluid switching valve occurs. When Pn is less than Ps, the controller sends an electronic signal to the flow switching device to start the next piston stroke after a time delay as indicated in the time vs. pressure charts seen in Fig. 7A-7B.
See below for updated rejections.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 05/08/2026 has been considered by the examiner.
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, 2, 5-10, 12, 14-22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Noble et al. (US 7739941), hereinafter ‘Noble’.
Noble renders obvious:
1. (Currently Amended) An apparatus (100) for recirculating hydraulic fluid in a hydraulic system, the hydraulic system including a hydraulic pump (140), a bypass valve (within valve 430, central position, in light of applicant’s new drawings, remarks, and claim 8, the limitation of “a bypass valve” does not need to be separate from the switching valve, a valve position as seen in applicant’s Fig. 5b meets the limitation of a bypass valve), a fluid switching valve (430)
a sub- circuit (circuit including 146, 144 and 112) and a controller (170), the hydraulic pump pressurizing hydraulic fluid for circulation through the hydraulic system, the sub-circuit comprising, a piston-bypass valve (124), a cylinder (112) and a piston (118) reciprocating therein between first and second cylinder heads (114, 116), the piston dividing the cylinder between a first chamber (120) adjacent the first cylinder head and a second chamber (122) adjacent the second cylinder head, first and second hydraulic lines (144, 146) fluidly connecting the first and second chambers to the fluid switching valve (430), respectively, hydraulic fluid entering and leaving the sub-circuit through entry and exit ports on the fluid switching valve, respectively, the piston-bypass valve (124) selectively fluidly connecting the first and second chambers, the controller operatively connected to the fluid switching valve and programmed to command first and second actuating positions, in the first actuating position the entry and exit ports are fluidly connected to the second and first chambers through the second and first hydraulic lines, respectively, in the second actuating position the entry and exit ports are fluidly connected to the first and second chambers through the first and second hydraulic lines, respectively (see left and right positions of valve 430),
the controller operatively connected to the bypass valve and programmed to command the bypass valve to a bypass position where pressurized hydraulic fluid bypasses the sub-circuit (central position of valve 430 is the bypass valve position within valve 430 consistent with applicant’s valve 130 seen in applicant’s new Fig. 5b dated 11/27/2025 in light of applicant’s remarks stating that Fig. 5b shows an integrated switching valve that includes the bypass valve 140 can be part of fluid switching valve 130), the apparatus comprising the controller programmed to:
command the fluid switching valve to the first actuating position, the piston-bypass valve being is closed such that pressurized hydraulic fluid moves the piston towards the first cylinder head during a first stroke (Col. 15 line 21-46 renders obvious the valve 430 in actuating positions to pressurize the respective chambers of the actuator 110, when the valve 430 is in an actuating position, the bypass valve/bypass center position is “closed”, i.e. not connected);
detect when the piston has completed the first stroke and is adjacent the first cylinder head (Col. 13 lines 34-43 “Controller 170 in the described embodiments in programmable to determine when the piston has reached the end of each piston stroke based upon at least one of hydraulic pump speed, hydraulic fluid pressure, or elapsed time. The information that is used by controller 170 to make this determination is measured during each piston stroke.”);
delay commanding:
a. the fluid switching valve to the second actuating position (Noble Col. 15 line 32-37 states that at time t3 the controller actuates the flow switching device, and states at time t2 is when the shuttle valve 124 is opened due to the stem contacted an end of the housing. There is a time between t2 and t3 after the pressure has dropped and has been detected by the pressure sensor, and before the control signal is sent to the switching valve which is indicated by the small horizontal line between t2 and t3, which is a delay in sending the control signal to the flow control valve.
Furthermore, Noble, claim 14 also recites “wherein said controller adds a predetermined delay to the timing for sending said electronic signal to said flow switching device so that said piston is stationary for at least a predetermined time between each piston stroke" which indicates a delay exists after determining that the piston is at the end of its stroke and before the control signal to the fluid switching valve occurs. When Pn is less than Ps, the controller sends an electronic signal to the flow switching device to start the next piston stroke after a time delay as indicated in the time vs. pressure charts seen in Fig. 7A-7B),
b. the bypass valve to the bypass position, or
c. the hydraulic pump to stop pressurizing the hydraulic fluid,
whereby after the piston completes the first stroke, the piston-bypass valve is open such that hydraulic fluid is fluidly communicated into the sub- circuit through the entry port and through the piston-bypass valve wherein a quantity of hydraulic fluid is flushed out of the sub-circuit through the exit port (valve 124 opens when it engages the cylinder ends via ends 126, 127); and
after the quantity of hydraulic fluid is flushed out of the sub-circuit, command:
a. the fluid switching valve to the second actuating position (Col. 15 lines 21-46),
b. the bypass valve to the bypass position, or
c. the hydraulic pump to stop pressurizing the hydraulic fluid (during a future operation cycle of the device of Noble, it would have been obvious to one of ordinary skill in the art to recognize that the pump would stop pressurizing the hydraulic fluid at some point, or would operate the switching valve to the bypass or second actuating position as desired).
2. (Original) The apparatus as claimed in claim 1, wherein the piston-bypass valve is a shuttle valve configured in the piston (valve including 124), pressurized hydraulic fluid closing the shuttle valve in the first actuating position at the beginning of the first stroke and the shuttle valve opening when the piston completes the first stroke (valve member 124 closes the opening on the piston chamber 120 side when fluid pressurizes chamber 122 to move the piston in the retracting direction).
5. (Currently Amended) The apparatus as claimed in claim 1, wherein after detecting the end of the first stroke and before the quantity of hydraulic fluid is flushed out of the sub-circuit, the controller is further programmed to stop the hydraulic pump and then restart the hydraulic pump after a time interval (Col. 11 lines 45-54 discloses a pressure sensor which detects the end of the first stroke between t2 and t3, Col. 15 lines 1-10, the pump stops operation between t3 and t4, Col. 15 lines 21-46, the pressure does not increase during t3 and t4 indicating the pump is stopped and then restarted after t4 to increase the pressure to P1 to drive the piston within the cylinder; it would have been obvious to one of ordinary skill in the art at the time the invention was filed to have either recognize or modified the pump to stop during t3 and t4 because the piston is not controlled to move during this time).
6. (Currently Amended) The apparatus as claimed in claim 1, wherein after detecting the end of the first stroke and before the quantity of hydraulic fluid is flushed out of the sub-circuit, the controller is further programmed to command the bypass valve to the bypass position and then to a non-bypass position after a time interval (the device is operated in a reciprocating manner, when beginning the first stroke, the valve 430 is in the position seen in Fig. 4 which has the bypass valve of the center position closed; when the piston is fully retracted, the valve 430 would switch from its position seen in Fig. 4 to the center position at least for a time which means the bypass valve position is open, and then repeats during the reciprocating operation of the device)
7. (Currently Amended) The apparatus as claimed in claim 1, wherein when the fluid switching valve is commanded to the second actuating position, and the piston-bypass valve is closed, the controller is further programmed to: detect when the piston has completed a second stroke and is adjacent the second cylinder head;
delay commanding:
a. the fluid switching valve to the second actuating position (Noble Col. 15 line 32-37 states that at time t3 the controller actuates the flow switching device, and states at time t2 is when the shuttle valve 124 is opened due to the stem contacted an end of the housing. There is a time between t2 and t3 after the pressure has dropped and has been detected by the pressure sensor, and before the control signal is sent to the switching valve which is indicated by the small horizontal line between t2 and t3, which is a delay in sending the control signal to the flow control valve.
Furthermore, Noble, claim 14 also recites “wherein said controller adds a predetermined delay to the timing for sending said electronic signal to said flow switching device so that said piston is stationary for at least a predetermined time between each piston stroke" which indicates a delay exists after determining that the piston is at the end of its stroke and before the control signal to the fluid switching valve occurs. When Pn is less than Ps, the controller sends an electronic signal to the flow switching device to start the next piston stroke after a time delay as indicated in the time vs. pressure charts seen in Fig. 7A-7B),
b. the bypass valve to the bypass position, or
c. the hydraulic pump to stop pressurizing the hydraulic fluid,
whereby after the piston completes the second stroke, the piston-bypass valve is open such that hydraulic fluid is fluidly communicated into the sub-circuit through the entry port and through the piston-bypass valve wherein the quantity of hydraulic fluid is flushed out of the sub-circuit through the exit port; and
after the quantity of hydraulic fluid is flushed out of the sub-circuit,
command:
a. the fluid switching valve to the first actuating position (during reciprocation operation of the device of Noble, the switching valve 14 would be commanded alternatingly between the first and second actuating position to extend and retract the piston; see Col. 15 lines 21-46, Col. 13 lines 15-43),
b. the bypass valve to the bypass position, or
c. the hydraulic pump to stop pressurizing the hydraulic fluid (when the device is shut down after completing a second stroke, the pump would stop pressurizing as claimed).
8. (Previously Presented) The apparatus of claim 1, wherein the bypass valve is part of the fluid switching valve, whereby the fluid switching valve is actuatable to the first actuating position, the second actuating position and the bypass position (see Noble Fig. 4, center position of valve 430 is the bypass position).
9. (Original) The apparatus of claim 1, wherein the quantity of hydraulic fluid that is flushed out of the sub-circuit is greater than, equal to or less than a fluid volume of the sub-circuit (the amount flushed out of the sub-circuit including 144, 146, 112 during a flushing operation between t2 and t3 is greater than, equal to, or less than a fluid volume of the sub-circuit inherently).
10. (Original) The apparatus as claimed in claim 1, wherein the quantity of hydraulic fluid flushed out of the sub-circuit is the quantity of hydraulic fluid flushed when a temperature of the hydraulic fluid is within a desired operating temperature range (absent further limitations, this appears to be implicitly met by the amount of fluid flushed out during t2 and t3 in the device of Noble, since no temperature range is specified, the implicit temperature that the fluid is at in the device of Noble meets this limitation).
12. (Currently Amended) The apparatus as claimed in claim 1, wherein the quantity of hydraulic fluid flushed out of the sub-circuit is the quantity of hydraulic fluid flushed after a flush time-interval or when a pressure of hydraulic fluid decreases below a desired value (absent further limitations, this appears to be implicitly met by the amount of fluid flushed out during t2 and t3 in the device of Noble).
14. (Currently Amended) A method for recirculating hydraulic fluid in a hydraulic system, the hydraulic system including a hydraulic pump, a bypass valve, a fluid switching valve, a sub- circuit and a controller, the hydraulic pump pressurizing hydraulic fluid for circulation through the hydraulic system, the sub-circuit comprising a piston-bypass valve, a cylinder and a piston reciprocating therein between first and second cylinder heads, the piston dividing the cylinder between a first chamber adjacent the first cylinder head and a second chamber adjacent the second cylinder head, first and second hydraulic lines fluidly connecting the first and second chambers to the fluid switching valve, respectively, hydraulic fluid entering and leaving the sub-circuit through entry and exit ports on the fluid switching valve, respectively, the piston-bypass valve selectively fluidly connecting the first and second chambers, the controller operatively connected to the fluid switching valve and programmed to command first and second actuating positions, in the first actuating position the entry and exit ports are fluidly connected to the second and first chambers through the second and first hydraulic lines, respectively, in the second actuating position the entry and exit ports are fluidly connected to the first and second chambers through the first and second hydraulic lines, respectively, the controller operatively connected to the bypass valve and programmed to command the bypass valve to a bypass position where pressurized hydraulic fluid bypasses the sub-circuit, the method comprising: supplying pressurized hydraulic fluid to the second chamber and closing the piston-bypass valve to move the piston towards the first cylinder head during a first stroke; detecting when the piston has completed [[a]] the first stroke and is adjacent the first cylinder head;
delay commanding:
a. the fluid switching valve to the second actuating position (Noble Col. 15 line 32-37 states that at time t3 the controller actuates the flow switching device, and states at time t2 is when the shuttle valve 124 is opened due to the stem contacted an end of the housing. There is a time between t2 and t3 after the pressure has dropped and has been detected by the pressure sensor, and before the control signal is sent to the switching valve which is indicated by the small horizontal line between t2 and t3, which is a delay in sending the control signal to the flow control valve.
Furthermore, Noble, claim 14 also recites “wherein said controller adds a predetermined delay to the timing for sending said electronic signal to said flow switching device so that said piston is stationary for at least a predetermined time between each piston stroke" which indicates a delay exists after determining that the piston is at the end of its stroke and before the control signal to the fluid switching valve occurs. When Pn is less than Ps, the controller sends an electronic signal to the flow switching device to start the next piston stroke after a time delay as indicated in the time vs. pressure charts seen in Fig. 7A-7B),
b. the bypass valve to the bypass position, or
c. the hydraulic pump to stop pressurizing the hydraulic fluid,
whereby after the piston completes the first stroke, the piston-bypass valve is open such that hydraulic fluid is fluidly communicated into the sub- circuit through the entry port and through the piston-bypass valve wherein a quantity of hydraulic fluid is flushed out of the sub-circuit through the exit port; and performing after the quantity of hydraulic fluid is flushed out of the sub- circuit:
a. supplying pressurized hydraulic fluid to the first chamber and closing the piston-bypass valve to cause the piston to move towards the second cylinder head,
b. bypassing the pressurized hydraulic fluid from the sub-circuit, or
c. stopping the hydraulic pump from pressurizing the hydraulic fluid (see claim 1 rejection for equivalent limitation mapping and discussion).
15. (Currently Amended) The method as claimed in claim 14, wherein after detecting the end of the first stroke and before the quantity of hydraulic fluid is flushed out of the sub-circuit, further comprising stopping a hydraulic pump that pressurizes and supplies hydraulic fluid to the sub- circuit and then restarting the hydraulic pump after a time interval (see claim 5 rejection for equivalent limitation mapping and discussion).
16. (Currently Amended) The method as claimed in claim 14, wherein after detecting the end of the first stroke and before the quantity of hydraulic fluid is flushed out of the sub-circuit, further comprising bypassing hydraulic fluid from the sub-circuit and then supplying the hydraulic fluid to the sub-circuit after a time interval (see claim 6 rejection for equivalent limitation mapping and discussion).
17. (Currently Amended) The method as claimed in claim 14, wherein when pressurized hydraulic fluid is supplied to the first chamber and the piston-bypass valve is closed to cause the piston to move towards the second cylinder head, the method further comprising: detecting when the piston has completed a second stroke and is adjacent the second cylinder head,
delaying:
a. supplying pressurized hydraulic fluid to the second chamber and closing the piston-bypass valve to cause the piston to move towards the first cylinder head (Noble Col. 15 line 32-37 states that at time t3 the controller actuates the flow switching device, and states at time t2 is when the shuttle valve 124 is opened due to the stem contacted an end of the housing. There is a time between t2 and t3 after the pressure has dropped and has been detected by the pressure sensor, and before the control signal is sent to the switching valve 430 which is indicated by the small horizontal line between t2 and t3, which is a delay in sending the control signal to the flow control valve 430 which prevents supplying pressurized hydraulic fluid to the second chamber and closing the piston-bypass valve to cause the piston to move towards the first cylinder head.
Furthermore, Noble, claim 14 also recites “wherein said controller adds a predetermined delay to the timing for sending said electronic signal to said flow switching device so that said piston is stationary for at least a predetermined time between each piston stroke" which indicates a delay exists after determining that the piston is at the end of its stroke and before the control signal to the fluid switching valve occurs. When Pn is less than Ps, the controller sends an electronic signal to the flow switching device to start the next piston stroke after a time delay as indicated in the time vs pressure charts seen in Fig. 7A-7B. Since not delay duration has been claimed, any delay between the determination of end of stroke has occurred, and the control signal being sent out meets this limitation),
b. bypassing the pressurized hydraulic fluid from the sub-circuit, or
c. stopping the hydraulic pump that pressurizes the hydraulic fluid through the piston-bypass valve,
whereby after the piston completes the second stroke, the piston-bypass valve is open such that hydraulic fluid is fluidly communicated into the sub-circuit through the entry port and through the piston-bypass valve wherein the quantity of hydraulic fluid is flushed out of the sub-circuit through the exit port; and performing after the quantity of hydraulic fluid is flushed out of the sub- circuit:
a. supplying pressurized hydraulic fluid to the second chamber and closing the piston-bypass valve to cause the piston to move towards the first cylinder head,
b. bypassing the pressurized hydraulic fluid from the sub-circuit, or
c. stopping the hydraulic pump from pressurizing the hydraulic fluid (see claim 7 rejection for equivalent limitation mapping and discussion).
18. (Original) The method of claim 14, wherein the quantity of hydraulic fluid that is flushed out of the sub-circuit is greater than, equal to or less than a fluid volume of the sub-circuit (see claim 9 rejection for equivalent limitation mapping and discussion).
19. (Original) The method as claimed in claim 14, wherein the quantity of hydraulic fluid flushed out of the sub-circuit is the quantity of hydraulic fluid flushed when a temperature of the hydraulic fluid is within a desired operating temperature range or when a pressure of hydraulic fluid decreases below a desired value (see claim 10 rejection for equivalent limitation mapping and discussion).
20. (Original) The method as claimed in claim 14, wherein the quantity of hydraulic fluid flushed out of the sub-circuit is the quantity of hydraulic fluid flushed after a flush time-interval (see claim 12 rejection for equivalent limitation mapping and discussion).
Allowable Subject Matter
Claim 3 and 4 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.
The following is a statement of reasons for the indication of allowable subject matter: The prior art does not appear to disclose nor render obvious a piston-bypass valve that is operatively connected to the controller as claimed in claims 3 and 4 (Fig. 11 and 12 embodiment), in combination with their respective base claim limitations.
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 June 17, 2026
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