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 .
Status of the Claims
Examiner acknowledges receipt of Applicant’s amendments and arguments filed with the Office on August 27th, 2026 in response to the Non-Final Office Action mailed on June 2nd, 2026. Per Applicant's response, Claims 1, 7-8, 11-15, & 19-20 have been amended. Claim 2 has been cancelled. All other claims have been left in their previously-presented form. Consequently, Claims 1 & 3-20 now remain pending in the instant application. The Examiner has carefully considered each of Applicant’s amendments and/or arguments, and they will be addressed below.
Claim Rejections - 35 USC § 112
Claim 11 was 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. Applicant’s amendments to the claims have remedied this issue, rendering the rejection moot.
Response to Arguments
Applicant's arguments filed August 27th, 2026 have been fully considered but they are not persuasive. The Examiner’s responses can be seen below.
In regards to Applicant’s argument that “Vlot does not teach, suggest, or disclose that during the changeover, the first pump is executing the first discharge stroke and the second pump is executing the second discharge stroke such that the first pump is configured to discharge material during the changeover and the second pump is configured to discharge material during the changeover. As can be clearly seen in the drawings of Vlot (such as FIG. 7), as the first piston is ramping down in speed, the second piston is increasing speed to cause pre-compression in the "'waiting cylinder." Nothing in Vlot suggests that both the first piston and the second piston are executing discharge strokes at the same time such that the first pump and the second pump are both configured to discharge material during the changeover. The intersection of the lines in FIG. 7 shows the time at which the first piston and the second piston are moving at the same speed, not that both pistons are in the discharge stroke, as alleged in the Office Action. Page 5. The red vertical line seen in annotated FIG. 7 above represents the time at which the second piston begins the discharge stroke, which is the same time at which the first piston begins the suction stroke. As stated in Vlot, the first cylinder takes over from the second cylinder when piston #2 has reached its end position and returned to suction. Page 6. Vlot does not teach, suggest, or disclose that during the changeover, the first pump is executing the first discharge stroke and the second pump is executing the second discharge stroke such that the first pump is configured to discharge material during the changeover and the second pump is configured to discharge material during the changeover”, the Examiner must respectfully disagree. Applicant’s position above ultimately fails because it is based on an incorrect analysis of Vlot’s Figure 7 and its corresponding disclosures. Applicant takes the position that Vlot does not depict (or describe) both pistons (i.e. piston #1 and piston #2) in the discharge stroke simultaneously such that both pistons are configured to discharge material (i.e. paste) during the changeover, as now claimed. However, Applicant’s position is simply incorrect. While Applicant argues that Figure 7 does not depict both pistons simultaneously in a discharge stroke, the Examiner respectfully maintains that simultaneous discharge strokes is precisely what Figure 7 does depict. In Figure 7, a plotted line above the X-axis represents a piston in its discharge stroke (as clearly labeled on Figure 7; “Discharge stroke cyl. #1”; “Discharge stroke cyl. #2”). Conversely, a plotted line below the X-axis represents a piston in its suction stroke (as clearly labeled on Figure 7; “Suction stroke cyl. #2”; “Suction stroke cyl. #1”). In other words, when a plotted line is above the X-axis, that piston is moving at a positive (or forward) speed. Conversely, when a plotted line is below the X-axis, that piston is moving at a negative (or reverse) speed. The slope of each line, as noted by Applicant, indicates the rate of acceleration (or deceleration) of the corresponding piston during its stroke. When a plotted line is flat, that piston is moving at a constant speed. Therefore, given all of these facts, the intersection of the two plotted lines at the upper middle region of Figure 7 represents both pistons performing their respective discharge strokes simultaneously, with piston #1 decelerating (indicated by the downward slope) and piston #2 accelerating (indicated by the upward slope). This simultaneous discharge stroke operation is made further apparent on page 6 under “System Design”, and is specifically disclosed as resulting in “generation of constant flow”. The Examiner attempted to make this point clear in the rejection of Claim 2 in the previous office action, and is reiterating the same position with further detail herein for absolute clarity and expeditious prosecution. Applicant’s position is that the discharge strokes of the two pistons do not overlap, and thus, a discontinuous output flow results in Vlot. However, this position directly contradicts the clear disclosures (and Figure 7 depiction) in Vlot, which makes clear that an overlapping of accelerating and decelerating discharge strokes of the two pistons eliminates both pressure pulsations and discontinuous output flow from the pump. In other words, the underlined portion of Applicant’s assertion “The intersection of the lines in FIG. 7 shows the time at which the first piston and the second piston are moving at the same speed, not that both pistons are in the discharge stroke, as alleged in the Office Action” is clearly incorrect. Applicant’s annotation of a vertical line into Vlot’s Figure 7 represents a continued misunderstanding of Vlot’s Figure 7, and does nothing to override the clear disclosure of Vlot, as detailed above. Finally, Applicant’s argument that one piston “takes over” for the other also does nothing to override the clear disclosures in Vlot, as detailed above. Therefore, for all of these reasons, the Examiner must respectfully maintain that Vlot does, in fact, disclose Applicant’s invention as previously recited in Claims 1 & 2, and continues to disclose Applicant’s Claim 1 as now recited. Thus, Applicant’s arguments are not persuasive.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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, 3, 6-10, 12-20 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by “Pulsation Free Hydraulically driven Piston Pump” to Vlot (attached herein; published February 2017; Vlot hereinafter).
PNG
media_image1.png
518
1196
media_image1.png
Greyscale
PNG
media_image2.png
582
1124
media_image2.png
Greyscale
PNG
media_image3.png
514
1148
media_image3.png
Greyscale
In regards to independent Claim 1, and with particular reference to Figures 1 & 7-8 shown immediately above, Vlot discloses:
1. A multi-piston pump (Fig. 8) comprising: a first pump (upper piston pump; Fig. 8) configured to execute a first discharge stroke, a first suction stroke, a first compression stroke, a first hold, and a changeover (all apparent in Fig. 7 and page 6); a second pump (lower piston pump; Fig. 8) independent from the first pump (“driving both pistons independently of each other”; page 6), the second pump being configured to execute a second discharge stroke, a second suction stroke, a second compression stroke, a second hold, and the changeover (all apparent in Fig. 7 and page 6); and a controller (“programmable logic controller PLC”; page 6) that coordinates operation of the first pump and the second pump so that: while the first pump is executing the first discharge stroke, the second pump is executing the second suction stroke, the second compression stroke, and the second hold (Fig. 7 and page 6), and the first pump and the second pump execute the changeover simultaneously (Fig. 7 and page 6); and while the second pump is executing the second discharge stroke, the first pump is executing the first suction stroke, the first compression stroke, and the first hold (Fig. 7 and page 6), and the first pump and the second pump execute the changeover simultaneously (Fig. 7 and page 6); wherein during the changeover, the first pump is executing the first discharge stroke and the second pump is executing the second discharge stroke such that the first pump is configured to discharge a material during the changeover and the second pump is configured to discharge the material during the changeover (Fig. 7 and page 6; see also the “Response to Arguments” section above, which details precisely why Vlot continues to disclose these limitations).
In regards to Claim 3, the first pump comprises a first linear position sensor (“a linear transducer system which is integrated on the hydraulic side of each cylinder”; page 6) configured to sense and send to the controller position information of the first pump (page 6), and the second pump comprises a second linear position sensor (“a linear transducer system which is integrated on the hydraulic side of each cylinder”; page 6) configured to sense and send to the controller position information of the second pump (page 6).
In regards to Claim 6, the multi-piston pump is configured to output a continuous volumetric output during the changeover between the first pump and the second pump (“constant discharge flow”; page 6; “flow is nearly constant”; page 8 ; see also Figs. 7 & 10).
In regards to Claim 7, during the first discharge stroke of the first pump, a first discharge poppet valve fluidly connected to a first delivery cylinder of the first pump is open (page 2 and Fig. 1), and during the second discharge stroke of the second pump, a second discharge poppet valve fluidly connected to a second delivery cylinder of the second pump is open (page 2 and Fig. 1).
In regards to Claim 8, during the first suction stroke of the first pump, a first suction poppet valve fluidly connected to the first delivery cylinder is open and the first discharge poppet valve is closed (page 2 and Fig. 1), and during the second suction stroke of the second pump, a second suction poppet valve fluidly connected to the second delivery cylinder is open and the second discharge poppet valve is closed (page 2 and Fig. 1).
In regards to Claim 9, during the changeover between the first pump and the second pump, the first discharge poppet valve is open and the second discharge poppet valve is open (this is clearly implied by Vlot’s statement “When the pressure levels in both cylinders are equal, cylinder #2 will start its discharge stroke and take over from cylinder #1”; page 6; see also the top center region of Fig. 7, which shows an intersection at which both pistons are in the discharge stroke, with one piston ramping up in speed while the other ramps down in speed).
In regards to Claim 10, the first pump and the second pump are hydraulic pumps (page 1 and Fig. 1).
In regards to Claim 12, during the first compression stroke of the first pump, the first discharge poppet valve is closed and the first suction poppet valve is closed (this is implicit to allowing compression to occur; see also “Pre-compression in ‘waiting’ cylinder” in Fig. 7, and page 6), and during the second compression stroke of the second pump, the second discharge poppet valve is closed and the second suction poppet valve is closed (this is implicit to allowing compression to occur; see also “Pre-compression in ‘waiting’ cylinder” in Fig. 7, and page 6).
In regards to Claim 13, during the first compression stroke of the first pump, the pressure in the first delivery cylinder increases until the pressure in the first delivery cylinder is just below a pressure in the second delivery cylinder (Fig. 7 and page 6 make clear that such a pressure relationship occurs, at least momentarily; “in order to bring the pressure up to level of cylinder #1” requires the pre-compression pressure to momentarily reach a level that is “just below a pressure” in the other cylinder, as claimed), and during the second compression stroke of the second pump, the pressure in the second delivery cylinder increases until the pressure in the second delivery cylinder is just below a pressure in the first delivery cylinder (Fig. 7 and page 6 make clear that such a pressure relationship occurs, at least momentarily; “in order to bring the pressure up to level of cylinder #1” requires the pre-compression pressure to momentarily reach a level that is “just below a pressure” in the other cylinder, as claimed).
In regards to Claim 14, when the pressure in the first delivery cylinder is just below a pressure in the second delivery cylinder, the pressure in the first delivery cylinder is just below an opening pressure of the first discharge poppet valve (Fig. 7 and page 6 make clear that such a pressure relationship occurs; “When the pressure levels in both cylinders are equal, cylinder #2 will start its discharge stroke and take over from cylinder #1” implies that a pre-compression pressure just below the pressure within the other cylinder (i.e. just before “equal” pressure) is a pressure just before opening of the discharge poppet valve (“start its discharge stroke”), as claimed), and when the pressure in the second delivery cylinder is just below the pressure in the first delivery cylinder, the pressure in the second delivery cylinder is just below an opening pressure of the second discharge poppet valve (Fig. 7 and page 6 make clear that such a pressure relationship occurs; “When the pressure levels in both cylinders are equal, cylinder #2 will start its discharge stroke and take over from cylinder #1” implies that a pre-compression pressure just below the pressure within the other cylinder (i.e. just before “equal” pressure) is a pressure just before opening of the discharge poppet valve (“start its discharge stroke”), as claimed).
In regards to Claim 15, during the first hold of the first pump (circled region in Fig. 7 shows a hold for pump 2; the same can be seen at the right of Fig. 7 for pump 1), the pressure in the first delivery cylinder is just below a pressure in the second delivery cylinder (“pre-compression of the waiting cylinder #2, in order to bring the pressure up to level of cylinder #1. When the pressure levels in both cylinders are equal, cylinder #2 will start its discharge stroke and take over from cylinder #1” at page 6 clearly implies a ramping up of fluid pressure in one cylinder during pre-compression, which implicitly requires the pre-compressing pump to momentarily produce a pressure just below the pressure in the other pump, as claimed) and the second delivery cylinder is executing the second discharge stroke (Fig. 7 and page 6), and during the second hold of the second pump (circled region in Fig. 7 shows a hold for pump 2; the same can be seen at the right of Fig. 7 for pump 1), the pressure in the second delivery cylinder is just below a pressure in the first delivery cylinder (“pre-compression of the waiting cylinder #2, in order to bring the pressure up to level of cylinder #1. When the pressure levels in both cylinders are equal, cylinder #2 will start its discharge stroke and take over from cylinder #1” at page 6 clearly implies a ramping up of fluid pressure in one cylinder during pre-compression, which implicitly requires the pre-compressing pump to momentarily produce a pressure just below the pressure in the other pump, as claimed) and the first delivery cylinder is executing the first discharge stroke (Fig. 7 and page 6).
In regards to Claim 16, the multi-piston pump has a discharge pipe that is connected to the first delivery cylinder and the second delivery cylinder (shown best in Fig. 1).
In regards to Claim 17, the first suction poppet valve is an intake control valve for the first delivery cylinder, the first discharge poppet valve is an exhaust control valve for the first delivery cylinder, the second suction poppet valve is an intake control valve for the second delivery cylinder, and the second discharge poppet valve is an exhaust control valve for the second delivery cylinder (Fig. 1; pages 2 & 6-7).
In regards to Claim 18, the first pump comprises a first ram within the first delivery cylinder and the second pump comprises a second ram within the second delivery cylinder (both apparent in Fig. 8).
In regards to Claim 19, during the changeover from the first pump to the second pump, the first ram ramps down speed while the second ram ramps up speed (declaration and acceleration of the two pistons are clearly represented by the sloped lines in Fig. 7; see also the “Response to Arguments” section above), the pressure in the second delivery cylinder increasing to an opening pressure, and during the changeover from the second pump to the first pump, the second ram ramps down speed while the first ram ramps up speed, the pressure in the first delivery cylinder increasing to the opening pressure (detailed in pages 6-7 and shown in Fig. 7; “the suction stroke is performed at a higher speed than the discharge stroke”).
In regards to Claim 20, a rate of rearward movement of the first ram is greater than a rate of forward movement of the second ram when the first pump is executing the first suction stroke, and a rate of rearward movement of the second ram is faster than a rate of forward movement of the first ram when the second pump is executing the second suction stroke (detailed in pages 6-7 and shown in Fig. 7; “the suction stroke is performed at a higher speed than the discharge stroke”).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 4-5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vlot (applied above) in view of US 2020/0072201 to Marica.
In regards to Claims 4-5, Vlot discloses the invention of Claim 3, but does not further disclose that the first pump comprises a first pressure sensor configured to sense and send to the controller pressure information of the first pump, and the second pump comprises a second pressure sensor configured to sense and send to the controller pressure information of the second pump, wherein the controller coordinates operation of the first pump and the second pump based upon position information of the first pump, position information of the second pump, pressure information of the first pump, and pressure information of the second pump, as claimed in Claims 4-5.
However, Marica discloses another multi-piston pump (Fig. 1) for wellbore operations (paras. 3-4) and in which first and second piston pumps (60; Fig. 1) pump fluid from a suction manifold (12) to a discharge manifold (14) and controlled by an electronic controller (50) (Fig. 1) such that “pressurized drilling fluid is continuously fed to the drill string at a substantially constant rate” (para. 4). Marica further discloses that the first pump comprises a first pressure sensor (52) configured to sense and send to the controller pressure information of the first pump (para. 25), and the second pump comprises a second pressure sensor (52) configured to sense and send to the controller pressure information of the second pump, as claimed (para. 25). Marica further discloses the use of linear position sensors (54) communicating with the controller (50), similar to Vlot. Marica makes clear that by monitoring both position and pressure of each pump, optimized control of pump operations is obtained (para. 25). Therefore, to one of ordinary skill desiring a multi-piston pump that ensures optimizes pump operations through multiple sensed variables (i.e. position and pressure), it would have been obvious to utilize the techniques disclosed in Marica in combination with those seen in Vlot in order to obtain such a result. Consequently, it would have been obvious to one of ordinary skill in the art at a time before the effective filing date of the claimed invention to have modified Vlot’s piston pumps with respective pressure sensors (52) connected to Vlot’s controller (as taught in Marica) in order to obtain predictable results; those results being pump control system that ensures optimal pump operation that considers not only pump position but also pump pressure.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vlot (applied above) in view of CN 106014903 to Gong (attached herein with machine translation).
In regards to Claim 11, Vlot discloses the multi-piston pump of claim 10, but does not further disclose that hydraulic fluid is routed to a piston to tank orifice after completion of the first discharge stroke and the second discharge stroke, as claimed.
However, Gong discloses yet another hydraulically driven multi-piston pump (Fig. 1) for pumping slurry, concrete, etc. (paras. 2-4) and in which first and second piston pumps (11/12/13 & 21/22/23; Fig. 1) pump fluid from an intake to an outlet via respective poppet valves (72, 73) (paras. 64-109). Gong further discloses that hydraulic fluid is routed to a piston to tank orifice (3, 4, which both contain orifices 6) after completion of the discharge strokes (para. 65), thereby allowing for quick return of hydraulic fluid to the tank as needed while “enabling a smooth transition in pumping reversal and keeping the flow rate and pressure of the pumped material relatively stable” (para. 39). Therefore, to one of ordinary skill desiring a multi-piston pump that can provide quick return of the pistons as needed in order to maintain stable output flow/pressure, it would have been obvious to utilize the techniques disclosed in Gong in combination with those seen in Vlot in order to obtain such a result. Consequently, it would have been obvious to one of ordinary skill in the art at a time before the effective filing date of the claimed invention to have modified Gong’s oil return lines with respective orifices (6) (as taught in Gong) in order to obtain predictable results; those results being pump control system that can provide for quick return of the pump pistons, and thus, stable output flow/pressure.
Conclusion
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 ALEXANDER BRYANT COMLEY whose telephone number is (571)270-3772. The examiner can normally be reached Monday-Friday 9AM-6PM CST.
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, Mark Laurenzi can be reached at 571-270-7878. 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.
/ALEXANDER B COMLEY/Primary Examiner, Art Unit 3746
ABC
