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 .
Response to Arguments
Applicant’s arguments, see Remarks, filed 2 December 2025, with respect to the rejection(s) of claim(s) 5-9 under 35 USC 112a have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made under 35 USC 103 in view of Zhou et al (CN 210660616 U) and Liu et al (CN 109114047 A).
Applicant’s arguments, see Remarks, filed 2 December 2025, with respect to the rejection(s) of claim(s) 1-4 under 35 USC 103 have been fully considered and are not persuasive.
Applicant argues that Liu ‘047 is directed to preventing backflow, not to the buoyancy problem addressed by the present application. The examiner respectfully points out that by preventing backflow, the invention of Liu ‘047 performs the same operating principle as the instant application where the claimed/disclosed flange impedes flow and/or increases flow resistance thereby allowing less fluid to flow into a cavity between the impeller and casing. Therefore, since the claimed structural limitations are disclosed by Liu ‘047 and performs in the same operating principle of preventing fluid flow or allowing less fluid to flow in a cavity, the arguments are not persuasive.
Applicant further argues that the structures of Zhou are used solely for blocking foreign matter, and are not able to control fluid-induced buoyancy at all. The examiner respectfully points out that when the structures of Zhou are rotating and blocking foreign matter, flow resistance is also increased when compared to an impeller without the structures of Zhou, thereby performing in the same operating principle of the instant application. Furthermore, the proposed modification of Zhou in view of Liu ‘047, enhances the blocking of foreign matter and the reduction of fluid flow into a cavity between the impeller and casing. For these reasons the arguments are not persuasive.
Applicant further argues that Liu ‘047 invention concerns about negative pressure after shutdown. The examiner respectfully points out that the claim rejections are based on a proposed combination of Zhou in view of Liu ‘047, whereas the teachings of Liu ‘047 are used to modify the fluid impeding structures of Zhou to make it a single continuous ring. Both Zhou and Liu ‘047 deal with decreasing and/or preventing fluid from entering a cavity between an impeller and casing, therefore, the arguments are not persuasive. Note that in response to applicant's arguments against the references individually, 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).
Applicant further argues that a person having ordinary skill in the art, after reviewing Zhou ‘616 and Liu ‘047, would not derive the concept of providing a “single continuous closed annular flange” on the outer edge of the impeller bottom surface. The examiner respectfully points out that a person of ordinary skill in the art would be able to readily apply a modification to the structures of Zhou ‘616, which are placed on an outer edge of the impeller bottom surface, with the teachings of a single continuous closed annular flange from Liu ‘047 since both disclosures address a similar operating principle which helps decreasing and/or preventing fluid from entering a cavity between an impeller and casing. Even with Liu ‘047 disclosure of the single continuous closed annular flange being located on a top front cover instead of the bottom surface, the concept of decreasing and/or preventing fluid from entering a cavity between an impeller and casing could be applied to both a cavity on a top front portion of an impeller and a bottom portion of said impeller.
For the reasons above, the arguments are not found persuasive and the claims are being rejected, see below.
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 (611) 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).
Zhou does not explicitly teach the annular fluid-impeding flange being a single continuous structure disposed around an outer edge of the impeller bottom surface or the impeller top surface 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 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 (611) 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 continuous structure disposed around an outer edge of the impeller bottom surface or the impeller top surface 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 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 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