DETAILED ACTION
Receipt and entry of Applicant’s Preliminary Amendment dated December 16, 2025 is acknowledged.
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, 11-14, and 17-18 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Franco et al. (Franco) (Patent/Publication Number 4,203,503).
Regarding claims 1, 11, and 13, Franco discloses a muffler (2), comprising: a cylindrical housing (2) defining an anechoic chamber (10, 14, 18, 26, 38, 50), wherein the cylindrical housing comprises an axis (Figures 1-2); an anechoic chamber inlet (6) and an anechoic chamber outlet (54) located at opposite axial ends of the cylindrical housing (2) (e.g. See Column 2, lines 24-40; column 3, lines 19-40); a partition plate (8, 12, 16, 28, 40) located in the anechoic chamber, wherein the partition plate is arranged substantially perpendicular to the axis of the cylindrical housing and divides the anechoic chamber (10, 14, 18, 26, 38, 50) into at least two compartments (10, 14, 18, 26, 38, 50) (e.g. See Column 2, lines 24-67; column 3, lines 1-40); a muffling pipe (20, 22, 30, 32, 34, 36), arranged on the partition plate and extending first distance along the axis on at least one side of the partition plate, wherein the muffling pipe defines a travel channel penetrating through the partition plate (e.g. See Column 2, lines 57-67: As shown, particularly in FIG. 2, the fourth baffle-plate 28 has four tubular ducts, comprising stub-pipes 30, 32, 34, 36, each with a respective stiffening collar and an internal diameter of 60 millimeters. The respective centres of the stub-pipes 30, 32, 34, 36 are arranged about a circumference with a diameter of 180 millimeters which is concentric with the longitudinal axis of the body 2. The stub-pipes 30, 32, 34, 36 extend for a length of 46 millimeters, including the stiffening collar, within the first expansion chamber 26 and have slightly flared ends. The pipes 30, 32, 34, 36 also extend for a length of 54 millimeters into a second expansion chamber 38 which is defined by a fifth, similarly convex, baffle-plate 40, located 320 millimeters from the fourth plate 28.) (e.g. See Column 2, lines 56-67; column 3, lines 1-20); and a liquid discharging pipe (42, 44, 46, 48, 54), provided on the partition plate (28, 40) and extending a second distance along the axis on at least one side of the partition plate, wherein the liquid discharging pipe defines a liquid discharging channel penetrating through the partition plate (e.g. See Column 3, lines 3-18: As shown in FIG. 3, the fifth baffle-plate 40 has four tubular ducts, comprising stub-pipes 42, 44, 46, 48, each with a respective stiffening collar and an internal diameter of 60 millimeters. These pipes 42, 44, 46, 48 are arranged, angularly displaced by 45.degree., with respect to the pipes 30, 32, 34, 36 on the fourth baffle-plate 28, about a circumference with a diameter of 180 millimeters which is concentric with the longitudinal axis of the body 2.) (e.g. See Column 2, lines 56-67; column 3, lines 1-40), and the liquid discharging pipe is arranged in contact with the cylindrical housing or is partially formed by the cylindrical housing, wherein, a position of the anechoic chamber outlet relative to the liquid discharging pipe is configured to enable liquid flowing out from the liquid discharging pipe to flow through the anechoic chamber outlet (e.g. See Column 2, lines 24-67; column 3, lines 1-40); and wherein the liquid discharging pipe is provided with a plurality of communication holes (24) to communicate an internal space of the liquid discharging pipe with a corresponding compartment in which the liquid discharging pipe is located (e.g. See Column 2, lines 24-67).
Regarding claim 12, Franco further discloses wherein: the anechoic chamber outlet is axially aligned with the liquid discharging pipe (e.g. See Column 2, lines 24-67; column 3, lines 1-40).
Regarding claim 14, Franco further discloses wherein: during use of the muffler, the axis of the cylindrical housing is arranged horizontally relative to a horizontal plane, the liquid discharging pipe is located at a bottom of the anechoic chamber, and the anechoic chamber outlet is axially aligned with the liquid discharging pipe at the bottom of the anechoic chamber, or during use of the muffler, the axis of the cylindrical housing is arranged obliquely relative to the horizontal plane (e.g. See Column 2, lines 24-67; column 3, lines 1-40).
Regarding claim 17, Franco further discloses a plurality of partition plates including the partition plate, wherein the liquid discharging pipe connects two adjacent partition plates of the plurality of partition plates, and the liquid discharging channel penetrates through the two adjacent partition plates of the plurality of partition plates (e.g. See Column 2, lines 40-56: The induction pipe 6 extends for an additional 34 millimeters to open into a first gas expansion chamber 26 which is defined by the third baffle-plate 16 and a fourth, convex, baffle-plate 28 located 330 millimeters from the third plate. The fourth baffle-plate 28 is similar to the aforesaid baffle-plates 8, 12, 16 in having a radius of curvature of 500 millimeters.) (e.g. See Column 2, lines 24-67; column 3, lines 1-40).
Regarding claim 18, Franco further discloses wherein the partition plate is adjacent to the anechoic chamber outlet and connects the partition plate to the anechoic chamber outlet (e.g. See Column 2, lines 24-67; column 3, lines 1-40).
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.
Claims 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Franco et al. (Franco) (Patent/Publication Number 4,203,503) in view of design choice.
Regarding claim 15, Franco discloses all the claimed limitation as discussed above except a total cross-section of the liquid discharging channel defined by the liquid discharging pipe provided on at least one partition plate of the plurality of partition plates is 0.1%-30% of a cross-section of the at least one partition plate of the plurality of partition plates.
Regarding the specific range of the total cross-section of the liquid discharging channel, it is the examiner’s position that a range between about 0.1%-30% of a cross-section of the at least one partition plate, 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 exhaust gas, as well as the size of the engine and silencer, properties of materials for making the silencer, and the controlled temperature of the silencer. 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.
Regarding claim 16, Franco further discloses wherein: a first portion of the liquid discharging pipe along a circumferential direction is defined by the cylindrical housing, and a second portion of the liquid discharging pipe is define by an additional wall, wherein a cross-sectional shape of the liquid discharging pipe is non-circular, or the liquid discharging pipe is defined by a pipe with a circular cross-section (e.g. See Column 2, lines 24-67; column 3, lines 1-40).
Allowable Subject Matter
Claims 2-10 are 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.
Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure and consists of seven patents:
Lee et al. (Pat./Pub. No. US 2024/0167403), Wagmann et al. (Pat./Pub. No. US 2023/0399963), LeRoy et al. (Pat./Pub. No. US 2017/0218806), Huang et al. (Pat./Pub. No. US 2016/0230627), Kato et al. (Pat./Pub. No. US 2012/0228055), Herold et al. (Pat./Pub. No. US 5801344), and Yashiro et al. (Pat./Pub. No. US 5614699), all discloses an exhaust gas purification for use with an internal combustion engine.
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
June 12, 2026
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