Prosecution Insights
Last updated: April 19, 2026
Application No. 18/308,381

HYBRID POWERTRAIN FOR A PUMP SYSTEM

Non-Final OA §102§103
Filed
Apr 27, 2023
Examiner
COMLEY, ALEXANDER BRYANT
Art Unit
3746
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Caterpillar Inc.
OA Round
3 (Non-Final)
57%
Grant Probability
Moderate
3-4
OA Rounds
3y 8m
To Grant
96%
With Interview

Examiner Intelligence

Grants 57% of resolved cases
57%
Career Allow Rate
536 granted / 941 resolved
-13.0% vs TC avg
Strong +39% interview lift
Without
With
+39.1%
Interview Lift
resolved cases with interview
Typical timeline
3y 8m
Avg Prosecution
36 currently pending
Career history
977
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
42.5%
+2.5% vs TC avg
§102
25.6%
-14.4% vs TC avg
§112
29.0%
-11.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 941 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 . 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 January 8th, 2026 has been entered. Response to Arguments Applicant’s arguments with respect to claim(s) 1-7 & 9 have been considered but are moot due to the new grounds of rejection necessitated by Applicant’s amendments. Please refer to the new rejections below. 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)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claim(s) 1-4, 7, & 9 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by US 2023/0340866 to Aune et al. PNG media_image1.png 590 886 media_image1.png Greyscale In regards to independent Claim 1, and with particular reference to Figure 9-10, Aune et al. (Aune) discloses: 1. A pump system (900), comprising: a hybrid powertrain (904-914), comprising: a gaseous fuel engine (906) a transmission (910) coupled to the gaseous fuel engine; a driveshaft (908) coupled to the transmission; a hydraulic fracturing pump (914) coupled to the driveshaft (i.e. indirectly, via the transmission); and a motor system (904) coupled to the hybrid power train; a power source (918) electrically connected to the motor system; and a controller (922) configured to: cause the hybrid powertrain to operate in a hybrid mode (“A first mode”; “preload the reciprocating gas engine”; Abstract & paras. 79 & 85-92) based on a determination (1002; Fig. 10) that an upshift of the transmission is to be performed (“prior to the upshifting of gears”; “an upshift or downshift”; Abstract & paras. 19 & 85); monitor a flow rate or a pressure of the hydraulic fracturing pump (“P” and “Q” in Equation 1; paras. 86-90; see also paras. 93-106, which give a functional example in which pressure and flow rate values from a pump performance table are used to calculate torque levels during the hybrid mode); adjust a torque distribution between the gaseous fuel engine and the motor system based at least in part on the flow rate or the pressure of the hydraulic fracturing pump (Steps 1004-1006; paras. 85-92); and cause the gaseous fuel engine and the motor system to operate according to the torque distribution such that the motor system assists or brakes the gaseous fuel engine in driving the hydraulic fracturing pump (Steps 1008-1010; paras. 85-92); and cause performance of the upshift after causing the gaseous fuel engine and the motor system to operate according to the torque distribution (Step 1012; paras. 85-92) In regards to Claim 2, the power source is an energy storage system or grid power (“battery”; para. 81). In regards to Claim 3, the controller, to determine the torque distribution, is configured to: determine the torque distribution based on the flow rate (“Q” in Equation 1; paras. 86-90; see also paras. 93-106, which give a functional example in which flow rate values from a pump performance table are used to calculate torque levels during the hybrid mode) In regards to Claim 4, the motor system comprises a motor (904) and a motor drive (“control circuitry”; paras. 24, 57) for the motor. In regards to Claim 7, the motor system comprises an electric motor (904), and wherein the electric motor is coupled to the transmission via a power take-off component (116; Fig. 1; also see “dual electric machine 904 is operably coupled to drive one end of a reciprocating gas engine 906”; para. 78), and the electric motor is mechanically or fluidly coupled to the power take-off component (Fig. 1 & para. 78). In regards to Claim 9, the motor system is configured to provide electrical power to the power source when braking the gaseous fuel engine (para. 79). 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. Claims 1-5 & 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 2019/0178235 to Coskrey et al. in view of US 2023/0340866 to Aune et al. In regards to independent Claim 1, and with particular reference to Figures 1-3, Coskrey et al. (Coskrey) discloses: 1. A pump system (100; Fig. 1), comprising: a hybrid powertrain (130c), comprising: a gaseous fuel engine (130a) a transmission (130d) coupled to the gaseous fuel engine; a driveshaft (not shown; disclosed at para. 12) coupled to the transmission; a hydraulic fracturing pump (130b) coupled to the driveshaft (para. 12); and a motor system (130e; see also “variable frequency drive”; para. 21) coupled to the hybrid powertrain; a power source (“sources of electricity include, but are not limited to, an on-site electrical generator, a public utility grid, one or more power storage elements, solar cells, wind turbines, other power sources, or one or more combinations of any of the previously listed sources”) electrically connected (via 130f) to the motor system (para. 15); and a controller (190) configured to: cause the hybrid powertrain to operate in a hybrid mode based on a determination that a transition is occurring (para. 19); determine a torque distribution between the gaseous fuel engine and the motor system based at least in part on the transition (“transient operations”) of the hydraulic fracturing pump (para. 19); and cause the gaseous fuel engine and the motor system to operate according to the torque distribution such that the motor system assists or brakes the gaseous fuel engine in driving the hydraulic fracturing pump (Fig. 2; paras. 23-24). While Coskrey discloses much of Applicant’s recited invention, including adjusting the torque distribution between the engine and motor “during transmission gear-shift events” (i.e. transitions; see paras. 18-19), he does not specifically disclose: 1) the hybrid mode is caused due to a determination that an upshift of the transmission is to be performed, 2) monitoring flow rate or pressure of the pump and adjust a torque distribution between the gaseous fuel engine and the motor system based at least in part on the flow rate or the pressure, or 3) causing performance of the upshift after causing the gaseous fuel engine and the motor system to operate according to the torque distribution. In other words, while Coskrey implies performing his hybrid mode during shifts, he does not disclose the particular timing of events recited in the claim. However, Aune (described previously above) discloses another fracturing pump assembly (Fig. 9) similar to Coskrey in which a hybrid drivetrain (904-914) drives a frac pump (914) through a transmission (910) and driveshaft (908) in order to provide a fracturing operation. Aune goes on to specifically disclose 1) causing the hybrid powertrain to operate in a hybrid mode (“A first mode”; “preload the reciprocating gas engine”; Abstract & paras. 79 & 85-92) based on a determination (1002; Fig. 10) that an upshift of the transmission is to be performed (“prior to the upshifting of gears”; “an upshift or downshift”; Abstract & para. 85), 2) monitoring a flow rate or a pressure of the hydraulic fracturing pump (“P” and “Q” in Equation 1; paras. 86-90; see also paras. 93-106, which give a functional example in which pressure and flow rate values from a pump performance table are used to calculate torque levels during the hybrid mode), 3) adjusting a torque distribution between the gaseous fuel engine and the motor system based at least in part on the flow rate or the pressure of the hydraulic fracturing pump (Steps 1004-1006; paras. 85-92), 4) causing the gaseous fuel engine and the motor system to operate according to the torque distribution such that the motor system assists or brakes the gaseous fuel engine in driving the hydraulic fracturing pump (Steps 1008-1010; paras. 85-92), and 5) cause performance of the upshift after causing the gaseous fuel engine and the motor system to operate according to the torque distribution (Step 1012; paras. 85-92). In other words, Aune makes clear that it is well known in the art of frac pump hybrid powertrains to adjust the torque distribution based on both impending upshifts and design pressures/flow rates in order to ensure that a minimum speed is always maintained, thereby avoiding shutdown of the system. Stated another way, Aune discloses the claimed timing of the torque distribution adjustment relative to the impending upshift event for the purpose of stabilizing operation of the pump system; something Coskrey fails to detail as it relates to his gearshift events. Therefore, to one of ordinary skill desiring a frac pump hybrid powertrain that prevents under speed shutdown scenarios due to impending shifting events, it would have been obvious to utilize the techniques disclosed in Aune in combination with those seen in Coskrey 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 Coskrey’s pump system with the shift and pressure/flow-based torque adjustment methodology of Aune (i.e. Fig. 10) in order to obtain predictable results; those results being a hybrid powertrain that continuously adjusts the torque distribution based on transient shifting/pressure/flow conditions. In regards to Claim 2, Coskrey discloses the power source is an energy storage system or grid power (paras. 15 & 24). In regards to Claim 3, Coskrey discloses the controller, to determine the torque distribution, is configured to: determine the torque distribution based on the flow rate (this results via the combination with Aune, see Claim 1 above; see also the “stages” at paras. 18-19 of Coskrey). In regards to Claim 4, Coskrey discloses the motor system comprises a motor (130e) and a motor drive (“variable frequency drive”) for the motor (para. 19). In regards to Claim 5, Coskrey discloses the motor system comprises an electric motor (130e), and wherein the electric motor is coupled in series between the gaseous fuel engine and the transmission (“second mover 130e may be positioned between the transmission 130d and the first mover 130a”; para. 13). In regards to Claim 9, Coskrey discloses that the motor system is configured to provide electrical power to the power source when braking the gaseous fuel engine (Fig. 2; paras. 23-24). Claim(s) 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Coskrey-Aune (applied above) in view of US 7,086,226 to Oguri. In regards to Claim 6, Coskrey discloses the pump system of Claim 5, but does not further disclose that the electric motor is coupled to the gaseous fuel engine via a clutch, as claimed. However, Oguri discloses another pump system (Fig. 1), comprising: a hybrid powertrain (1, 2, 8, 11), comprising: a gaseous fuel engine (1) a transmission (7, 15, 16) coupled to the gaseous fuel engine; a driveshaft (“a rotation shaft”; “output shaft”; col. 5, lines 26-32; see also Fig. 1) coupled to the transmission; a hydraulic pump (2) coupled to the driveshaft (Fig. 1; col. 5, lines 26-32; see also Fig. 1); and a motor system (11) coupled to the hydraulic fracturing pump (“the electric motor 11 can be provided on the same shaft as the rotation shaft of the hydraulic pump 2”; col. 9, lines 13-22); a power source (12) electrically connected to the motor system (Fig. 1); and a controller (5) configured to: determine a torque distribution between the gaseous fuel engine and the motor system based at least in part on whether a transient event (i.e. changing drive torque levels) is associated with the pump system (col. 5, line 60 – col. 8, line 6); and cause the gaseous fuel engine and the motor system to operate according to the torque distribution such that the motor system assists or brakes the gaseous fuel engine in driving the hydraulic fracturing pump (col. 5, line 60 – col. 8, line 6). Oguri further discloses that the electric motor (11) is coupled to the gaseous fuel engine (1) via a clutch (18), as claimed. Oguri discloses that via the clutch 18, various combinations of engine and motor drive power can be obtained easily by the controller 5. Therefore, to one of ordinary skill desiring a hybrid powertrain with easily connectable/disconnectable drive sources, it would have been obvious to utilize the techniques disclosed in Oguri in combination with those seen in Coskrey 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 Coskrey with a clutch in between the engine and electric motor (as taught in Oguri) in order to obtain predictable results; those results being a simplistic, controllable means of connecting/disconnecting the drive sources depending on need. Allowable Subject Matter Claims 21-24 are allowed. Claim 8 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. The following is a statement of reasons for the indication of allowable subject matter: the best available prior art fails to disclose a motor system that assists or brakes a gaseous fuel engine in driving a hydraulic fracturing pump, as recited in claim 1, wherein the motor system further comprises: a hydraulic machine; a hydraulic pump to drive the hydraulic machine; and an electric motor to drive the hydraulic pump, wherein the hydraulic machine is coupled to the transmission via a power take-off component. Applicant’s specification discloses that through the arrangement recited in claim 8, the gaseous fuel engine may be turned off to facilitate driving the fracturing pump in an electric-only mode using the hydraulic machine via the power take-off component. The best available prior art fails to disclose such a particular motor system arrangement; much less the electric-only mode using the hydraulic machine via the power take-off component described by Applicant in the specification. The best available prior art references not already applied above are: 1. US 2023/0340866 to Aune et al. (applied above) 2. US 2021/0396121 to Wilson 3. US 6,708,787 to Naruse et al. Although each of the above-noted references generally discloses a powertrain for driving a hydraulic pump, none of the references disclose a motor system as recited in claim 8, in combination with the engine, transmission, driveshaft, and controller methodology recited in claim 1. As such, the invention, as recited in claim 8, appears to be novel and non-obvious over the best available prior art. Conclusion 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
Read full office action

Prosecution Timeline

Apr 27, 2023
Application Filed
Jul 22, 2025
Non-Final Rejection — §102, §103
Oct 01, 2025
Interview Requested
Oct 02, 2025
Interview Requested
Oct 08, 2025
Applicant Interview (Telephonic)
Oct 08, 2025
Examiner Interview Summary
Oct 13, 2025
Response Filed
Oct 20, 2025
Final Rejection — §102, §103
Nov 25, 2025
Interview Requested
Dec 03, 2025
Applicant Interview (Telephonic)
Dec 03, 2025
Examiner Interview Summary
Dec 08, 2025
Response after Non-Final Action
Jan 08, 2026
Request for Continued Examination
Feb 17, 2026
Response after Non-Final Action
Feb 18, 2026
Non-Final Rejection — §102, §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12601338
RECIPROCATING PUMP WITH RESERVOIR FOR COLLECTING AND CONTROLLING WORKING FLUID LEVEL WITHOUT THE USE OF PISTON SEALS
2y 5m to grant Granted Apr 14, 2026
Patent 12601343
COOLING FOR BELLOWS PUMP
2y 5m to grant Granted Apr 14, 2026
Patent 12584475
OIL PRESSURE SUPPLY DEVICE
2y 5m to grant Granted Mar 24, 2026
Patent 12584440
TURBOCHARGER CONTROL SYSTEM FOR REDUCTION OF ROTATIONAL SPEED FLUCTUATION
2y 5m to grant Granted Mar 24, 2026
Patent 12582107
PUMPS IN SERIAL CONNECTION
2y 5m to grant Granted Mar 24, 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

3-4
Expected OA Rounds
57%
Grant Probability
96%
With Interview (+39.1%)
3y 8m
Median Time to Grant
High
PTA Risk
Based on 941 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