DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12 August 2026 has been entered.
Response to Arguments
Applicant’s arguments, see Remarks, filed 12 August 2026, with respect to the claim rejections under 35 USC 103 have been fully considered and are not persuasive.
Applicant argues that Zhou ‘616 cannot be considered to disclose the structure now claimed with respect to the impeller bottom surface or the impeller top surface being planar in a radial direction, the examiner respectfully points out the argument appears to attach extra limitations not required by the claim. Note that applicant’s disclosed impeller includes planar surfaces with elements extending away from the planar surfaces, similar to applicant’s annotations of Zhou ‘616, see below.
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Furthermore, Zhou ‘616 does disclose the impeller bottom surface being planar in a radial direction, at least in a portion which meets the claim limitation, see below.
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Applicant further argues that were the examiner’s simple-substitution rationale actually carried out – replacing the bossed structure on the impeller bottom surface of Zhou ‘616 with a single continuous flange – the annular grooves (612) between adjacent bosses (611) would no longer exist, the examiner respectfully disagrees with the characterization of the proposed modification. Note that the claim rejection clearly points to Zhou ‘616 annular fluid-impeding flange as the flange 611 disposed on the outer edge, and the proposed modification in view of Liu ‘047 is substituting said flange 611 disposed on the outer edge (which is not explicitly disclosed as a single annular flange), with a single annular fluid-impeding flange and single continuous structure based on the teachings of Liu ‘047. Therefore, the applicant arguments point to a different modification from what is actually being proposed in the claim rejections.
Applicant further argues that Liu ‘047 does not teach or suggest that providing only one annular flange on the impeller surface achieves the recited effect of reducing upward buoyancy during operation and that the focus of Liu ‘047’s teaching is the multi-ring cooperation, not a single annular flange acting alone. The examiner respectfully points out that the instant argument attacks the proposed prior art references combination individually, in this case, Liu ’047 by itself. It has been established that one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Furthermore, note that the examiner is not proposing modifying Zhou ‘616 with all first, second and third annular protrusions of Liu ‘047, but instead the teaching of an annular protrusion 313a being a single continuous structure. For these reasons the argument is not persuasive.
Applicant further argues that the proposed combination would not necessarily achieve the claimed technical effect of reducing upward buoyancy during operation. The examiner respectfully points out that both Zhou ‘616 and Liu ‘047 perform in the operating principle of preventing fluid flow or allowing less fluid to flow in a cavity which is the same principle of the instant application which is the cause of the claimed technical effect. The Non-Final Rejection mailed on 26 January 2026, section 3, addresses a previously presented argument in more detail which is equivalent to the instantly presented argument.
For the above reasons, the arguments are not persuasive and the claim rejections are maintained.
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) 1-9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Zhou et al – hereafter Zhou – (CN 210660616 U) in view of Liu et al – hereafter Liu – (CN 109114047 A).
Regarding claim 1, Zhou teaches an impeller structure for a water pump rotor (Fig.1/2), comprising:
an impeller (60) including an impeller base (61), an impeller top cover (62), and a plurality of vanes (601) provided between the impeller base and the impeller top cover (Fig.1); the impeller top cover being provided with a centered eye (Fig.1); the impeller top cover having an outer side surface defining an impeller top surface (surface of 62 on opposite side of 601) and the impeller base having an outer side surface defining an impeller bottom surface (surface of 61 on opposite side of 601); and
wherein at least one of the impeller bottom surface and the impeller top surface is provided with an annular fluid-impeding flange disposed around an outer edge of the impeller bottom surface (611 disposed on outer edge) for reducing the upward force of fluid buoyancy occurring when the impeller rotates (note that the “reducing …” recitation is a functional limitation. It is well-settled that the manner of operating a device does not differentiate an apparatus claim from the prior art. Specifically, it has been held that a claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus” if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). MPEP 2114 II. It is also noted that apparatus claims must be structurally distinguishable from the prior art. Specifically, it has been held that “while features of an apparatus may be recited either structurally or functionally, claims directed to an apparatus must be distinguished from the prior art in terms of structure rather than function" In re Schreiber, 128 F.3d 1473, 1477-78, 44 USPQ2d 1429, 1431-32 (Fed. Cir. 1997). See also In re Swinehart, 439 F.2d 210, 212-13, 169 USPQ 226, 228-29 (CCPA 1971); and In re Danly, 263 F.2d 844, 847, 120 USPQ 528, 531 (CCPA 1959). MPEP 2114 I), the impeller bottom surface or the impeller top surface being planar in a radial direction extending inwardly from the annular fluid-impeding flange (see annotated Fig.2A above).
Zhou does not explicitly teach the annular fluid-impeding flange being a single annular fluid-impeding flange continuous structure and forming a closed ring shape along a circumferential direction of the impeller.
Liu teaches an impeller structure for a water pump rotor (Fig.7), comprising: an impeller (311/312/313) including an impeller base (311), an impeller top cover (313), and a plurality of vanes (312) provided between the impeller base and the impeller top cover (Fig.7); the impeller top cover being provided with a centered eye (Fig.7). Liu further teaches an annular fluid-impeding flange (313a) being a single annular fluid-impeding flange and single continuous structure disposed around an outer edge of one of the impeller surfaces (Fig.7) and forming a closed ring shape along a circumferential direction of the impeller (Fig.7).
It would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify the impeller structure of Zhou by having the annular fluid-impeding flange being a single continuous structure disposed around an outer edge of the impeller surface and forming a closed ring shape along a circumferential direction of the impeller based on the teachings of Liu because this would require a simple substitution of one known element (fluid impeding-flange of Zhou) for another (fluid impeding-flange of Liu) to obtain predictable results (preventing fluid from entering a space above or below an impeller).
Regarding claim 2, Zhou and Liu further teach the fluid-impeding flange is provided on around an outer periphery of the impeller bottom surface (Zhou Fig.2, 611 located at the bottom of the figure).
Regarding claim 3, Zhou and Liu further teach the impeller base and the impeller top cover are spaced from one another by a dividing space (Zhou Fig.1); the vanes being located in the dividing space (Zhou Fig.1); and the centered eye on the impeller top cover being communicable with the dividing space (Zhou Fig.1).
Regarding claim 4, Zhou and Liu further teach the impeller top surface is located on the outer side surface of the impeller top cover that faces upward (Zhou Fig.1; note upward is relative to the specific orientation of the impeller at a given moment, the instant impeller configuration when rotated 90 degrees in a clockwise direction will satisfy the claimed limitation), and the impeller bottom surface is located on the outer side surface of the impeller base that faces downward (Zhou Fig.1; note downward is relative to the specific orientation of the impeller at a given moment, the instant impeller configuration when rotated 90 degrees in a clockwise direction will satisfy the claimed limitation).
Regarding claim 5, Zhou teaches a water pump (Fig.1/2), comprising:
a volute casing (20) including an inlet (21), an outlet (not shown; machine translation 129, note outlet is arranged on the outer circumference of the pump (head, i.e., casing) 20), and a volute chamber (102); and the volute chamber being defined in the volute casing and communicable with the inlet and the outlet (Fig.1; machine translation 129); and
an impeller (60) being mounted in the volute chamber and including an impeller base (61), an impeller top cover (62), and a plurality of vanes (601) provided between the impeller base and the impeller top cover (Fig.1); the impeller top cover being provided with a centered eye (Fig.1); the impeller top cover having an outer side surface defining an impeller top surface (surface of 62 on opposite side of 601) and the impeller base having an outer side surface defining an impeller bottom surface (surface of 61 on opposite side of 601); and
wherein at least one of the impeller bottom surface and the impeller top surface is provided with an annular fluid-impeding flange disposed around an outer edge of the impeller bottom surface (611 disposed on outer edge), the impeller bottom surface or the impeller top surface being planar in a radial direction extending inwardly from the annular fluid-impeding flange (see annotated Fig.2A above), and the annular fluid-impeding flange is configured to reduce the upward force of fluid buoyancy occurring when the impeller rotates, thereby preventing friction between the impeller and the volute casing (note that the “to reduce …” recitation is a functional limitation. It is well-settled that the manner of operating a device does not differentiate an apparatus claim from the prior art. Specifically, it has been held that a claim containing a "recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus” if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987). MPEP 2114 II. It is also noted that apparatus claims must be structurally distinguishable from the prior art. Specifically, it has been held that “while features of an apparatus may be recited either structurally or functionally, claims directed to an apparatus must be distinguished from the prior art in terms of structure rather than function" In re Schreiber, 128 F.3d 1473, 1477-78, 44 USPQ2d 1429, 1431-32 (Fed. Cir. 1997). See also In re Swinehart, 439 F.2d 210, 212-13, 169 USPQ 226, 228-29 (CCPA 1971); and In re Danly, 263 F.2d 844, 847, 120 USPQ 528, 531 (CCPA 1959). MPEP 2114 I).
Zhou does not explicitly teach the annular fluid-impeding flange being a single annular fluid-impeding flange continuous structure and forming a closed ring shape along a circumferential direction of the impeller.
Liu teaches an impeller structure for a water pump rotor (Fig.7), comprising: an impeller (311/312/313) including an impeller base (311), an impeller top cover (313), and a plurality of vanes (312) provided between the impeller base and the impeller top cover (Fig.7); the impeller top cover being provided with a centered eye (Fig.7). Liu further teaches an annular fluid-impeding flange (313a) being a single annular fluid-impeding flange and single continuous structure disposed around an outer edge of one of the impeller surfaces (Fig.7) and forming a closed ring shape along a circumferential direction of the impeller (Fig.7).
It would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify the impeller structure of Zhou by having the annular fluid-impeding flange being a single annular fluid-impeding flange and single continuous structure disposed around an outer edge of the impeller surface and forming a closed ring shape along a circumferential direction of the impeller based on the teachings of Liu because this would require a simple substitution of one known element (fluid impeding-flange of Zhou) for another (fluid impeding-flange of Liu) to obtain predictable results (preventing fluid from entering a space above or below an impeller).
Regarding claim 6, Zhou and Liu further teach the fluid-impeding flange is provided on around an outer periphery of the impeller bottom surface (Zhou Fig.2, 611 located at the bottom of the figure).
Regarding claim 7, Zhou and Liu further teach the impeller base and the impeller top cover are spaced from one another by a dividing space (Zhou Fig.1); the vanes being located in the dividing space (Zhou Fig.1); and the centered eye on the impeller top cover being communicable with the dividing space (Zhou Fig.1).
Regarding claim 8, Zhou and Liu further teach the inlet is provided on an upper side of the volute casing (Zhou Fig.1; note upper side is relative to the specific orientation of the pump/impeller at a given moment, the instant pump/impeller configuration when rotated 90 degrees in a clockwise direction will satisfy the claimed limitation) and the outlet is provided on one of a left and a right side of the volute casing (Zhou Fig.1; note left/right side is relative to the specific orientation of the pump/impeller at a given moment, the instant pump/impeller configuration when rotated 90 degrees in a clockwise direction will satisfy the claimed limitation as supported by machine translation 129, outlet is arranged on the outer circumference of the pump (head, i.e., casing) 20)).
Regarding claim 9, Zhou and Liu further teach the impeller top surface is located on the outer side surface of the impeller top cover that faces upward (Zhou Fig.1; note upward is relative to the specific orientation of the impeller at a given moment, the instant impeller configuration when rotated 90 degrees in a clockwise direction will satisfy the claimed limitation), and the impeller bottom surface is located on the outer side surface of the impeller base that faces downward (Zhou Fig.1; note downward is relative to the specific orientation of the impeller at a given moment, the instant impeller configuration when rotated 90 degrees in a clockwise direction will satisfy the claimed limitation).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JUAN G FLORES whose telephone number is (571)272-3486. The examiner can normally be reached Monday - Friday, 8:30am - 5:30pm Pacific Time.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nathan E Wiehe can be reached at (571) 272-8648. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JUAN G FLORES/Primary Examiner, Art Unit 3745
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