DETAILED ACTION
This office action is in response to the amendment filed March 16, 2026.
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 .
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.
(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.
Claims 1-3, 5-7, 9-10, 13, and 15-19 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kosaka et al. (Kosaka) (Patent/Publication Number US 2014/0020656) without new matter.
Regarding claims 1-2, 13, and 18-19, Kosaka discloses a vehicle comprising: an internal combustion engine (ICE) (3) defining at least one cylinder (3a) (e.g. See Paragraphs [0043]); an exhaust system (5, 9) selectively fluidly connected to the at least one cylinder (e.g. See Paragraphs [0050]); at least one exhaust valve (5) selectively fluidly connecting the at least one cylinder to the exhaust system (e.g. See Paragraphs [0043]); an air intake plenum (8) selectively fluidly connected to the at least one cylinder (e.g. See Paragraphs [0043, 0050]); at least one intake valve (4) selectively fluidly connecting the air intake plenum to the at least one cylinder (e.g. See Paragraphs [0050] Note that when there is such a valve overlap time period, there occur, as described hereinafter, a phenomenon in which burned gases temporarily flow out of the cylinder 3a into an exhaust passage 9 (exhaust system) and thereafter flow into the cylinder 3a again, or a phenomenon in which burned gases temporarily flow through the cylinder 3a into an intake passage 8 (intake system) and thereafter flow into the cylinder 3a again. In the following description, such burned gases that temporarily flow out of the cylinder 3a into the exhaust passage 9 and thereafter finally flow back into the cylinder 3a before closing timing of the intake valve 4, as described above, will be referred to as "blown back gases", and the amount of the blown back gases will be referred to as the "blown back gas amount".) (e.g. See Paragraphs [0043, 0050]); a pressure sensor (32) connected to the air intake plenum configured for sensing gas pressure in the air intake plenum (e.g. See Paragraphs [0057-0058]); and a control unit (ECU 2) comprising a processor and a memory, the processor being communicatively coupled to the pressure sensor for receiving a signal representative of gas pressure in the air intake plenum (e.g. See Paragraphs [0058] The intake pressure sensor 32 (intake pressure parameter-obtaining means) detects a pressure Pin within the intake passage 8 (hereafter referred to as the "intake pressure Pin"), and delivers a signal indicative of the detected intake pressure Pin to the ECU 2. The intake pressure Pin is detected as an absolute pressure. ...), the memory storing computer-readable instructions which, when executed, cause the processor (ECU 2) to perform a method for detecting undesired exhaust backflow (New Matter) in an air intake plenum (8) of the internal combustion engine (ICE) comprising: a) determining a maximum gas pressure (Pin, PinAve) in the air intake plenum after an opening of an intake valve of the ICE while the intake valve is open (as such, during the valve overlap time period) (e.g. See Paragraphs [0063] Note that in the present embodiment, the ECU 2 corresponds to the intake pressure parameter-obtaining means, the exhaust pressure parameter-obtaining means, the time period parameter-obtaining means, scavenged gas amount-calculating means, scavenged gas production degree parameter-calculating means, minimum exhaust pressure-calculating means, average exhaust pressure-calculating means, minimum amplitude-calculating means, blown-back gas amount-calculating means, corrected blown-back gas amount-calculating means, internal EGR amount-calculating means, maximum exhaust pressure-calculating means, blown-back gas production degree-calculating means, and maximum amplitude-calculating means.) (e.g. See Paragraphs [0063, 0081, 0113, 0121-0122]); b) determining a reference pressure; c) comparing, by a control unit (ECU 2), the maximum gas pressure (PexMAX) to the reference pressure (PexMIN) (e.g. See Paragraphs [0076, 0113, 0118-0119, 0121-0122]); and d) concluding, by the control unit, a presence of exhaust backflow (as such, an internal EGR amount Gegr_int) in the air intake plenum in response to the maximum gas pressure being greater than the reference pressure (e.g. See Paragraphs [0118] Further, the blown-back gases are produced under the condition that the exhaust pressure Pex exceeds the intake pressure Pin, and hence the blown-back gas amount is highly correlated with the maximum exhaust pressure PexMAX during the valve overlap time period. In view of this, the basic blown-back gas amount GegrRV_Base is calculated by the equations (2) to (4), using the maximum exhaust pressure PexMAX, the average intake pressure PinAve, the correction coefficient Krv, etc., and hence it is possible to calculate the basic blown-back gas amount GegrRV_Base with accuracy.) (e.g. See Paragraphs [0111-0113, 0117-0119, 0121-0122]).
Regarding claim 3, Kosaka further discloses wherein comparing the maximum gas pressure to the reference pressure comprises determining a ratio of the maximum gas pressure over the reference pressure (e.g. See Equations 1-3; Paragraphs [0080, 0112-0114, 0118-0119]).
Regarding claim 5, Kosaka further discloses wherein: the maximum gas pressure is a first maximum gas pressure; the reference pressure is a second maximum gas pressure (e.g. See Equations 1-3; Paragraphs [0080, 0112-0114]); and the second maximum gas pressure is a maximum pressure of a pressure oscillation in the air intake plenum prior to the opening of the intake valve (4) while the intake valve is closed (e.g. See Paragraphs [0080, 0112-0114, 0118-0119]).
Regarding claim 6, Kosaka further discloses wherein the reference pressure is an average gas pressure in the air intake plenum over a predetermined range prior to the opening of the intake valve while the intake valve is closed (e.g. See Paragraphs [0081] As shown in the above equation (5), in the calculation of the total scavenged gas amount GegrScaALL, the differential pressure between the average intake pressure PinAve and the minimum exhaust pressure PexMIN is used. The reason for this is follows: As is clear by reference to the above-mentioned FIG. 4B and FIG. 5B, the scavenged gases are produced in the cross-hatched region during the valve overlap time period, i.e. the region in which the exhaust pressure Pex is below the intake pressure Pin, and hence the scavenged gas amount has characteristics that it is highly correlated with the differential pressure between the intake pressure Pin and the minimum exhaust pressure PexMIN which is a minimum value of the exhaust pressure Pex during the valve overlap time period. .....) (e.g. See Paragraphs [0075-0076, 0081]).
Regarding claim 7, Kosaka further discloses wherein: the predetermined range is between a first crank angle and second crank angle; the first crank angle being 180 degrees of crank angle or less before the opening of the intake valve; and the second crank angle is a crank angle at the opening of the intake valve (e.g. See Paragraphs [0053] The crank angle sensor 30 (time period parameter-obtaining means) delivers a CRK signal and a TDC signal, which are both pulse signals, to the ECU 2 along with rotation of the crankshaft 3c. Each pulse of the CRK signal is generated whenever the crankshaft 3c rotates through a predetermined crank angle (e.g. 1.degree.). The ECU 2 calculates a rotational speed NE of the engine 3 (hereinafter referred to as "the engine speed NE") based on the CRK signal. Further, the TDC signal indicates that the piston 3b in one of the cylinders 3a is in a predetermined crank angle position slightly before the TDC position of the intake stroke, and each pulse thereof is delivered whenever the crankshaft rotates through 1800, in the case of the four-cylinder engine 3 of the present embodiment.) (e.g. See Paragraphs [0053, 0123-0124, 0128]).
Regarding claim 9, Kosaka further discloses a), determining an engine speed (NE) (e.g. See Paragraphs [0053]); and performing steps a), b), c) and d) only in response to the engine speed being greater than a predetermined engine speed (e.g. See Paragraphs [0096] Next, the process proceeds to a step 26, wherein the correction coefficient Krv is calculated by searching a map shown in FIG. 11 according to the overlap angle OVL and the engine speed NE. In FIG. 11, OVL1 to OVLi (i is a positive integer) are predetermined values of the overlap angle OVL in which OVL1< . . . <OVLi is satisfied, and NE1 to NEj (j is a positive integer) are predetermined values of the engine speed NE in which NE1< . . . <NEj is satisfied. .....) (e.g. See Paragraphs [0053, 0078, 0096]).
Regarding claim 10, Kosaka further discloses determining an air charge (GAIR) of a cylinder of the ICE provided with the air intake valve (4); and performing steps a), b), c) and d) only in response to the air charge being greater than a predetermined air charge (e.g. See Paragraphs [0057-0058, 0091-0092, 0099]).
Regarding claim 15, Kosaka further discloses limiting a torque of the ICE in response to concluding the presence of exhaust backflow (e.g. See Paragraphs [0098, 0133]).
Regarding claim 16, Kosaka further discloses retarding an ignition angle of the ICE in response to concluding the presence of exhaust backflow (e.g. See Paragraphs [0052-0053]).
Regarding claim 17, Kosaka further discloses operating the ICE in a limp home mode in response to concluding the presence of exhaust backflow (e.g. See Paragraphs [0042-0045, 0123-0125]).
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.
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.
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Kosaka et al. (Kosaka) (Patent/Publication Number US 2014/0020656) in view of design choice.
Regarding claims 4, Kosaka discloses all the claimed limitation as discussed above except the presence of exhaust backflow in response to the ratio being greater than 1.02.
Regarding the specific range of the presence of exhaust backflow ratio, it is the examiner’s position that the ratio being greater than 1.02 of the exhaust backflow ratio, would have been an obvious matter of design choice well within the level of ordinary skill in the art, depending on variables such as mass flow rate of the intake gas, as well as the size of the engine, and intake/exhaust manifold, and the controlled temperature of the combustion chambers. Moreover, there is nothing in the record which establishes that the claimed parameters present a novel or unexpected result, and such modification, i.e. choosing from a finite number of predictable solutions, is not of innovation but of ordinary skill and common sense. (See KSR International Co. v. Teleflex Inc., 550 U.S.--, 82 USPQ2d 1385 (April 30, 2007)).
Under some circumstances, however, changes such as these may impart patentability to a process if the particular ranges claimed produce a new and unexpected result which is different in kind and not merely in degree from the results of the prior art. In re Dreyfus, 22 CCPA (Patents) 830, 73 F.2d 931, 24 USPQ 52; In re Waite et al., 35 CCPA (Patents) 1117, 168 F.2d 104, 77 USPQ 586. Such ranges are termed "critical" ranges, and the applicant has the burden of proving such criticality. In re Swenson et al., 30 CCPA (Patents) 809, 132 F.2d 1020, 56 USPQ 372; In re Scherl, 33 CCPA (Patents) 1193, 156 F.2d 72, 70 USPQ 204. However, even though applicant's modification results in great improvement and utility over the prior art, it may still not be patentable if the modification was within the capabilities of one skilled in the art. In re Sola, 22 CCPA (Patents) 1313, 77 F.2d 627, 25 USPQ 433; In re Normann et al., 32 CCPA (Patents) 1248, 150 F.2d 627, 66 USPQ 308; In re Irmscher, 32 CCPA (Patents) 1259, 150 F.2d 705, 66 USPQ 314. More particularly, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In re Swain et al., 33 CCPA (Patents) 1250, 156 F.2d 239, 70 USPQ 412; Minnesota Mining and Mfg. Co. v. Coe, 69 App. D.C. 217, 99 F.2d 986, 38 USPQ 213; Allen et al. v. Coe, 77 App. D.C. 324, 135 F.2d 11, 57 USPQ 136.
Claims 8 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Kosaka et al. (Kosaka) (Patent/Publication Number US 2014/0020656) in view of Hagari et al. (Hagari) (Patent/Publication Number US 2013/0245967).
Regarding claim 8, Kosaka discloses all the claimed limitation as discussed above except that the reference pressure is an ambient air pressure; and determining the reference pressure comprises sensing the ambient air pressure with an ambient air pressure sensor disposed outside of the air intake plenum.
Hagari teaches that it is conventional in the art, to use the reference pressure is an ambient air pressure (Pa); and determining the reference pressure comprises sensing the ambient air pressure with an ambient air pressure sensor (14) disposed outside of the air intake plenum (5) (e.g. See Paragraphs [0065] In addition to the individual above-mentioned sensors 2, 3, 7 and 8, an atmospheric pressure sensor 14 for measuring an ambient atmospheric pressure is connected to the ECU 20, so that the amount of intake air measured by the AFS 2, the degree of opening of the electronic control throttle 4 measured by the throttle position sensor 3, the intake manifold pressure measured by the intake manifold pressure sensor 7, the intake manifold temperature Tb measured by the intake temperature sensor 8, and the atmospheric pressure measured by the atmospheric pressure sensor 14 are inputted to the ECU 20.) (See Paragraphs [0055, 0065-0066, 0119]).
It would have been obvious to one having ordinary skill in the art at the time the invention was made, to use the reference pressure is an ambient air pressure; and determining the reference pressure comprises sensing the ambient air pressure with an ambient air pressure sensor disposed outside of the air intake plenum of Kosaka, as taught by Hagari for the purpose of controlling amount of intake air into the combustion chamber, so as to control the amount of exhaust backflow in the intake passage, and further improve the performance and the efficiency of the engine, since the use thereof would have been routinely practiced by those with ordinary skill in the art to maintain high purification efficiency of a catalyst system.
Regarding claim 11, Hagari further discloses determining a position (3) of a throttle valve (4) disposed upstream of the air intake plenum (5); and performing steps a), b), c) and d) only in response to the position of the throttle valve being greater than a predetermined position of the throttle valve (e.g. See Paragraphs [0225] In addition, the estimation device for a cylinder intake air amount and an internal EGR rate in an internal combustion engine according to the first embodiment of the present invention is provided with: the AFS 2 (an intake air amount detection unit) that is arranged at the upstream side of the electronic control throttle 4 (the throttle valve), and serves to detect an amount of intake air which passes through the throttle valve and is sucked into the engine 1 (the internal combustion engine); and the physical model that models a response delay of the intake system until the air having passed through the throttle valve comes into the cylinder.) (See Paragraphs [0053-0055, 0221, 0225]).
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Kosaka et al. (Kosaka) (Patent/Publication Number US 2014/0020656) in view of Kuzuyama (Patent/Publication Number US 2009/0099816).
Regarding claim 12, Kosaka discloses all the claimed limitation as discussed above except that storing a fault code in a memory in response to concluding the presence of exhaust backflow.
Kuzuyama teaches that it is conventional in the art, to use a fault code in a memory in response to concluding the presence of exhaust backflow (e.g. See Paragraphs [0071] Curves D2 and E1 drawn by solid lines in the timing chart of FIG. 5G indicate the operation states of the exhaust valves 17A and 17B and the intake valves 16A and 16B in the abnormal state shown in FIG. 5C. In such an abnormal state, the exhaust gas in the combustion chamber 112 is first returned to the intake passage 33 by the internal EGR and then re-circulated into the combustion chamber 112. In this case, the returned exhaust gas advances the intake amount increase initiation timing in SI combustion. Further, the intake air heated by the internal EGR may cause ignition and knocking.) (See Paragraphs [0058, 0060, 0069, 0071]).
It would have been obvious to one having ordinary skill in the art at the time the invention was made, to use the fault code in a memory in response to concluding the presence of exhaust backflow of Kosaka, as taught by Kuzuyama for the purpose of controlling amount of intake air into the combustion chamber, so as to control the amount of exhaust backflow in the intake passage, and further improve the performance and the efficiency of the engine, since the use thereof would have been routinely practiced by those with ordinary skill in the art to maintain high purification efficiency of a catalyst system.
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Kosaka et al. (Kosaka) (Patent/Publication Number US 2014/0020656) in view of Fulton et al. (Fulton) (Patent/Publication Number US 2022/0298979).
Regarding claim 14, Kosaka discloses all the claimed limitation as discussed above except that a visual indication on a display of a vehicle powered by the ICE in response to concluding the presence of exhaust backflow.
Fulton teaches that it is conventional in the art, to use a visual indication on a display (300, 304, 308) of a vehicle powered by the ICE in response to concluding the presence of exhaust backflow (e.g. See Paragraphs [0050] execution of an inverse model at 304, determination of FGNOx at 306, and sensor input to an observer at 308. The nested control system 300 also includes a first inner loop providing EVO timing control for delivery of internal EGR, a second inner loop providing EGR valve control for delivery of external EGR, and a third inner loop providing throttle control for adjusting a pressure gradient across an HP-EGR valve to increase EGR when desired. .....) (See Paragraphs [0049-0051, 0053]).
It would have been obvious to one having ordinary skill in the art at the time the invention was made, to use a visual indication on a display of a vehicle powered by the ICE in response to concluding the presence of exhaust backflow of Kosaka, as taught by Fulton for the purpose of controlling amount of internal EGR into the combustion chamber, so as to control the amount of exhaust backflow in the intake passage, and further improve the performance and the efficiency of the engine, since the use thereof would have been routinely practiced by those with ordinary skill in the art to maintain high purification efficiency of a catalyst system.
Allowable Subject Matter
Claim 20 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; and also to overcome the claim objections set forth in this Office action, such as to overcome the rejection(s) under 35 U.S.C. 101, 112 2nd paragraph, and double patenting.
Since allowable subject matter has been indicated, applicant is encouraged to submit Final Formal Drawings (If Needed) in response to this Office action. The early submission of formal drawings will permit the Office to review the drawings for acceptability and to resolve any informalities remaining therein before the application is passed to issue. This will avoid possible delays in the issue process.
Response to Arguments
Applicant’s arguments filed March 16, 2026 have been fully considered but they are not completely persuasive. Claims 1-20 are pending.
Applicant’s cooperation in amending the claims to overcome the claim rejection is appreciated. However, Applicants have amended claims 1-20 with a new matter as discussed above. Applicant has argued that support for the amended subject matter (as such, “detecting undesired exhaust backflow (New Matter) in an air intake plenum”) is disclosed in paragraph [0008]. The examiner respectfully disagrees with the argument that the detecting undesired exhaust backflow in an air intake plenum can be found in paragraphs [0008].
On the other hand, the patent to Kosaka et al. has disclosed in paragraphs [0065-0076]: “Accordingly, as shown in FIG. 4B, until a midpoint of the first half of the valve overlap time period is reached, Pex<Pin is satisfied, whereby scavenged gases are produced, and after Pex>Pin is satisfied, blown-back gases are produced. In this case, a cross-hatched area in FIG. 4B represents a region where the scavenged gases are produced. In the case where the scavenged gases and the blown-back gases are thus produced, the internal EGR amount is reduced by the amount of the scavenged gases. ….. [0069] As described above, according to the change of the length of the valve overlap time period, a ratio between the blown-back gas amount and the scavenged gas amount changes. Specifically, as the valve overlap time period is longer, the blown-back gas amount decreases and the scavenged gas amount increases. ….. [0072] For the above-described reasons, in the embodiment, the blown-back gas amount GegrRV is calculated, as shown in the following equation (1), ....”. It is well understood that the blown-back gas amount is well understood as an undesired exhaust backflow. Therefore; the rejection of claims 1-20 are maintained.
In addition, Kosaka et al. has also disclosed the step of determining a maximum gas pressure, as seen in paragraphs [0063] “Note that in the present embodiment, the ECU 2 corresponds to the intake pressure parameter-obtaining means, the exhaust pressure parameter-obtaining means, the time period parameter-obtaining means, scavenged gas amount-calculating means, scavenged gas production degree parameter-calculating means, minimum exhaust pressure-calculating means, average exhaust pressure-calculating means, minimum amplitude-calculating means, blown-back gas amount-calculating means, corrected blown-back gas amount-calculating means, internal EGR amount-calculating means, maximum exhaust pressure-calculating means, blown-back gas production degree-calculating means, and maximum amplitude-calculating means” as seen in paragraphs [0073-0076].
Applicant’s arguments with respect to claims 1-20 have been considered but are moot in view of the new ground(s) of rejection as discussed above.
Applicant’s amendment (Claims 1-20) 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 response to this final action is set to expire THREE MONTHS from the date of this action. In the event a first response 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 extension fee pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event will the statutory period for response expire later than SIX MONTHS from the date of this final action.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Primary Examiner Binh Tran whose telephone number is (571) 272-4865. The examiner can normally be reached on Monday-Friday from 8:00 a.m. to 4:00 p.m.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisors, Mark Laurenzi, can be reach on (571) 270-7878. The fax phone numbers for the organization where this application or proceeding is assigned are (571) 273-8300 for regular communications and for After Final communications.
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Binh Q. Tran
/BINH Q TRAN/
Primary Examiner, Art Unit 3748
May 29, 2026
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