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 .
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.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 05 September 2025 has been entered.
Drawings
The drawings are objected to as failing to comply with 37 CFR 1.84(p)(5) because they do not include the following reference sign(s) mentioned in the description: D2. notably, Fig 3 labels both the smaller and larger circles with D1. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Objections
Claim 6 is objected to because one instance of “, and Y is a second coefficient, wherein 1 degree/mm ≥ Y ≥ 0.04 degree/mm” should be removed
Appropriate correction is required.
Claim Interpretation
No claim limitations are interpreted under 112(f).
Analysis
The goal of this analysis is to find a relationship between the claimed first coefficient X and the angles α and β, as shown below.
[AltContent: textbox (Blade Leading Edge)]
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[AltContent: textbox (Blade Leading Edge)][AltContent: textbox (rest of blade)]
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R1 = ½ D1 and R2 = ½ D2
According to the claim, D1 = D2 + HX
So, 2R1 = 2R2 + HX
Subtracting, HX = 2R2 – 2R1
X = 2(R2 – R1)/H
But, (R2 – R1)/H = tangent β
So, X = 2 tangent β
On the other hand, the claimed range of X, from 0.02 to 0.35, corresponds to an angle β from 0.57° to 9.92° or an angle α from 89.43° to 80.08°.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1 and 6 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention.
Claim 1 recites the limitation “the chord length of each blade progressively and continuously increases from a suction port to the fixing disk.” This implies that the suction port is the end of the impeller opposite the fixing disk. Claim 1 further recites “a diameter D1 of a maximum inscribed circle of the suction port” and “D2 is a diameter of a minimum inscribed circle of the suction port.” This implies that the suction port is the entire radially inner side of the impeller blades and the interior cone-shaped space therebetween. This is consistent with the specification, such as at ¶34 “the suction port of the fan impeller is configured as a trumpet-like tapering structure”. Thus, it is not clear what constitutes the suction port, since different interpretations are required to make sense of different portions of the same claim.
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.
Claim 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by Zhou (CN 205117804).
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Regarding claim 1, Zhou (CN 205117804) discloses:
A centrifugal fan impeller (1, see Fig 1), comprising blades (13) and a fixing disk (12), the blades being forward-curved structures (Fig 4 shows the impeller in relation to the housing and discharge, which is consistent with forward-curved blades. The impeller in Fig 4 would rotate clockwise.) and fixed to the fixing disk, wherein in a height direction of each blade, the chord length of each blade progressively and continuously increases from a suction port to the fixing disk (see Fig 3), and
wherein a diameter D1 of a maximum inscribed circle of the suction port of the centrifugal fan impeller perpendicular to an axis is: D1=D2+HX, where D2 is a diameter of a minimum inscribed circle of the suction port of the centrifugal fan impeller perpendicular to the axis, H is the height of the blades, and X is a first coefficient, wherein 0.35 > X > 0.02.
Zhou discloses an angle β of 6° (¶14), and a range of 3° to 9° (¶13).
X = 2 tangent (6°) = 0.21
Thus, Zhou discloses X in the claimed range because 0.21 is in the range of 0.02 to 0.35.
Claim 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kang (KR 2019/0122058).
Regarding claim 1, Kang discloses:
A centrifugal fan impeller (10, see Fig 1, ¶5), comprising blades (12) and a fixing disk (100), the blades being forward-curved structures (¶5 “ends (11) bent in the direction of rotation (wing type)” as compared to the contrasting prior art in ¶8) and fixed to the fixing disk, wherein in a height direction of each blade, the chord length of each blade progressively and continuously increases from a suction port (length a, see Fig 3) to the fixing disk (length b is near the fixing disk, see Fig 3), and
wherein a diameter D1 of a maximum inscribed circle of the suction port of the centrifugal fan impeller perpendicular to an axis is: D1=D2+HX, where D2 is a diameter of a minimum inscribed circle of the suction port of the centrifugal fan impeller perpendicular to the axis, H is the height of the blades, and X is a first coefficient, wherein 0.35 > X > 0.02 (analysis below).
In one example, the blades are 75 mm high, a is 14.51 mm, and b is 21.37 mm (¶44).
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Examiner notes that side b does not represent a portion of the blade on the suction port, but rather b is below the disk. However, the trapezoidal blade has a consistent angle. Thus, using the given information to calculate the angle will give the angle that does occur all along the suction port/leading edge.
The angle β is tan-1(6.86/75) = 5.2°.
X = 2 tangent (5.2°) = 0.18
Thus, Kang discloses X in the claimed range.
Alternatively, Kang discloses that the inner diameter of the blade changes by 6.86 mm on each side of the impeller (a diameter of the impeller intersects two blades) over a height of 75 mm.
D1 = D2 + HX
D2 + 2(6.86) = D2 + 75X
x =13.72/75 = 0.18
Examiner notes that the portion of the blade that is 21.37 mm wide occurs under the fixing disc and is thus not actually aligned with a portion of the suction port. However, the trapezoidal blade has the same slope all along the leading edge. Thus, the value of X calculated for the whole blade will also hold true for the portion of the blade above the fixing disc and along the suction port.
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 6 is rejected under 35 U.S.C. 103 as being unpatentable over Kang (KR 2019/0122058) in view of Ueda (US 4,231,706).
Regarding claim 6, Kang does not disclose:
a maximum value φ2 of the intake angles of the blades is:
φ2= φ1+H×Y, where φ1 is a minimum value of the intake angles of the blades, H is a height of the blades, and Y is a second coefficient, wherein 1 degree/mm ≥ Y ≥ 0.04 degree/mm, and Y is a second coefficient, wherein 1 degree/mm ≥ Y ≥ 0.04 degree/mm.
Ueda teaches that the intake angle of the blade changes along the span of the blade to match (“agree”) with the relative flow angle (abstract, Fig 9). The text does not discuss the specific measure of the intake angle per unit height, but gives an example of a 12° total change in the graph of Fig 9. Ueda teaches that the agreement between the intake angle and the inlet relative flow angle reduces noise and flow separation (abstract, col 5 lines 29-38). Thus, variation of the intake angle is a result effective variable for noise and flow separation, as taught by Ueda.
According to MPEP 2144.05 §II.A, it has been held that "[W]here 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 Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). In this case, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have adjusted the rate of change of the intake angle of the fan of Kang to match the rate of change of the inlet relative flow angle for the incoming air, arriving at a value of 0.04 to 1 degree per millimeter, because it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art.
Further, Ueda’s example value of 12° over the 75 mm height of Kang gives 12/75 = 0.16 degrees/mm, which is in the claimed range of 0.04 to 1 degree/mm.
Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Regarding claim 1, Patti (US 20060051202) discloses:
A centrifugal fan impeller (¶1, see Fig 1), comprising blades (3) and a fixing disk (4), the blades being forward-curved structures (see arrow S in Fig 8, ¶55) and fixed to the fixing disk, wherein in a height direction of each blade, the chord length of each blade progressively and continuously increases from a suction port to the fixing disk (se Fig 3), and
wherein a diameter D1 of a maximum inscribed circle of the suction port of the centrifugal fan impeller perpendicular to an axis is: D1=D2+HX, where D2 is a diameter of a minimum inscribed circle of the suction port of the centrifugal fan impeller perpendicular to the axis, H is the height of the blades, and X is a first coefficient, wherein 0.35 > X > 0.02.
Patti discloses the angle β as shown in Patti Fig 3. This corresponds with the angle β in the drawings above. So X = 2 tangent β. Patti discloses a specific embodiment with β = 12.65° (¶35). In this case, X = 2 tangent (12.65°) = 0.49. Patti also discloses a range of values for β from 0° to 40° (¶33). This corresponds to a range of values for X from 0 to 1.67. This does not have sufficient specificity for anticipation.
Zhou (CN 111878455 A) discloses an angle β (b) between 10° and 20°. “In some embodiments, the inlet angle c at the leading edge is gradually reduced in the direction from the first wheel disc to the second wheel disc;
In some embodiments, the difference between the maximum inlet angle and the minimum inlet angle at the leading edge is less than or equal to 18 degrees”
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JP 2006200525 A discloses that typically difference in inlet angle along the blade leading edge would be 25 degrees. They think it is better to keep constant, so it varies 5°. Both are in claimed range.
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Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TOPAZ L ELLIOTT whose telephone number is (571)270-5851. The examiner can normally be reached Monday-Friday 7 a.m. - 4 p.m. EST.
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/TOPAZ L. ELLIOTT/Primary Examiner, Art Unit 3745