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 Amendment
The amendment submitted 12/04/2025 has been entered. Claims 1-2 remain pending. Claims 3-5 have been cancelled.
The amendments to the claims have overcome each and ever rejection under 35 USC 112 made in Non-Final Rejection mailed 09/11/2025 and those rejections are hereby withdrawn.
Response to Arguments
Applicant's arguments filed 12/04/2025 have been fully considered but they are not fully persuasive. The amendments have changed the scope of the claims necessitating new grounds of rejection. Please see new grounds of rejection below.
The Applicant argues the prior art does not teach all limitations of the claims since Suzuki teaches “an axial-flow fan whose blades are made of plastic” and that “axial-flow fan and the centrifugal fan have completely different structural principles. The Examiner respectfully disagrees. Applicant’s admitted prior art discloses the blades being made of metal and the blades of both axial and centrifugal fans accomplish the same thing in the same way and follow the same basic principles of fluid flow and aerodynamics.
The Applicant argues the prior art does not teach all limitations of the claims since “the warped portion 2a and the smooth fillet R are not equivalent to the continuous curved surface and the curved corner rotated along a specific angle of 3 to 6 degrees” as “the bent part [of Suzuki] has a smooth fillet R at a warped angle θ of 5 to 30 degrees”. The Examiner respectfully disagrees. The warped portion 2a and smooth fillet R are equivalent to the continuous curves surface and the curved corner of the claimed invention and 5 degrees is within the range of 3 to 6 degrees as claimed.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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) 1-2 is/are rejected under 35 U.S.C. 103 as being unpatentable over the admitted prior art as described by the Applicant in the present application in view of US 6796771 to Suzuki.
(a) Regarding claim 1:
(i) In the present application’s specification the Applicant admits as prior art (Pars 0003/0005, Figs 1-4) a centrifugal impeller, comprising:
a disk (1a, Fig 1), a cover (2a, Fig 1), and
a plurality of vanes (3a, Fig 1) manufactured by sheet metal stamping (Par 0003); wherein the plurality of vanes is disposed between the disk and the cover (Fig 1), and
each of the plurality of vanes comprises an inlet edge (upstream edges of vanes 3a corresponding to the starting point of vane profile line, Figs 1/5), an outlet edge (downstream edges of vanes 3a corresponding to the ending point of the vane profile line, Figs 1/5), a blade root (edge of vanes 3a adjacent disk 1a, Fig 1), and a blade top (edge of vanes 3a adjacent cover 2a, Fig 1);
the blade root is disposed along a first horizontal plane (reasonably disclosed in Fig 1), the blade top is disposed along a second horizontal plane (reasonably disclosed in Fig 1);
wherein the first horizontal plane and the second horizontal plane are perpendicular to a rotation axis L (reasonably disclosed in Fig 1), and the first horizontal plane and the second horizontal plane intersect the rotation axis L at two positions, respectively (reasonably disclosed in Fig 1);
the inlet edge and the outlet edge extend between the blade root and the blade top (reasonably disclosed in Fig 1);
the inlet edge is disposed adjacent to the rotation axis L with respect to the outlet edge (reasonably disclosed in Fig 1);
the inlet edge, the blade root, and the blade top confine a continuous curved surface (reasonably disclosed in Fig 1); and
a longitudinal axis extending parallel to the rotational axis (reasonably disclosed in Fig 1).
(ii) The admitted prior art does not disclose:
wherein a curved corner is disposed at a joint of the outlet edge and the blade top,
a joint line is disposed between the curved corner and the continuous curved surface, and
a top joint point is disposed between the joint line and the blade top;
the curved corner is bent along the longitudinal axis extending through the top joint point towards the rotation axis with respect to the continuous curved surface;
wherein the centrifugal impeller is intercepted by several planes perpendicular to the rotation axis L of the centrifugal impeller and intersecting with the first curve AG, to form a plurality of vane profile lines (must exist as defined); and
the third curve GH and the outlet edge intersect with the plurality of vane profile lines, forming a plurality of curves VO (must exist as defined).
(iii) Suzuki is also in the field of fans (see title) and teaches:
a plurality of vanes (blades 2, Figs 1-2), each of the plurality of vanes comprises an inlet edge (“the front edge”, Col 2 Lns 39-41; edge opposite point β, Fig 2), an outlet edge (“the rear edge”, Col 2 Lns 39-41; edge comprising point β, Fig 2), a blade root (edge of blades 2 adjacent boss 1, Fig 2), and a blade top (“the blade tip”, Col 2 Lns 39-41, Fig 2),
wherein a curved corner (warped portion 2a, Fig 2) is disposed at a joint of the outlet edge and the blade top (Fig 2);
the inlet edge, the blade root, and the blade top confine a continuous curved surface (surface of fan blade 2 excluding curved corner 2a, Fig 2);
a joint line is disposed between the curved corner and the continuous curved surface (line C, Fig 2), and
a top joint point (α, Fig 2) is disposed between the joint line and the blade top (Fig 2);
the curved corner is bent along a longitudinal axis (axis passing through point α, Figs 2-3) extending through the top joint point (Figs 2-3);
wherein the centrifugal impeller is intercepted by several planes perpendicular to the rotation axis L of the centrifugal impeller and intersecting with a first curve AG, to form a plurality of vane profile lines (must exist as defined);
a third curve GH and the outlet edge intersect with the plurality of vane profile lines, forming a plurality of curves VO (must exist as defined; Suzuki: chordwise distance between line C and the outlet edge, Fig 2); and lengths of the curves VO increase from a point G to a vertex A (Suzuki: chordwise distance between line C and the outlet edge increases from point β to the tip, Fig 2).
(iv) It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the plurality of vanes as disclosed by the Applicant’s admitted prior art with the above aforementioned curved corner as taught by Suzuki for the purpose of improving fluid flow without deteriorating the fluid flow on the inlet edge, reducing loss of power without causing a large influence on the loadings, and provide a fan having a high fan efficiency and a high performance (Col 1 Lns 51-56).
(v) The Examiner notes that the curved corner of the admitted prior art as modified by Suzuki curves toward the suction side of the vane (Suzuki: fillet R curves “toward upstream”, Col 2 Ln 64, Fig 3), therefore the curved corner of the admitted prior art as modified by Suzuki bends towards a center of a rotation axis L of the centrifugal impeller and along the longitudinal axis towards the rotation axis with respect to the continuous curved surface as claimed.
(vi) The limitation “a formation process of the curved corner is as follows: five vane profile lines are defined from the blade top to the blade root, dividing each of the vanes into four equal parts, a first vane profile line a is located at the blade top, a second vane profile line b is located at one quarter-length of each of the vanes, and a third vane profile line c is located at a half-length of each of the vanes; an ending point of the second vane profile line b is point B, and an ending point of the third vane profile line c is point C; point B and point C are connected to form curve BC, and the point G is located on the curve BC: a curved plane M is drawn along a scan path GA from the point G to the vertex A; the curved plane M intersects with a plurality of normal planes perpendicular to a rotation axis L to form line segments; with the point G as an origin, each of the line segments forms an angle f of 3 to 10 degrees with a tangent to each of the vane profile lines at the point G the curved plane M is rotated around a line segment toward a center of the rotation axis L by an angle of 3 to 6 degrees, so that the curved plane M intersects with the vane to form a third curve GH: further, a region AGH is bent toward the curved plane M and coincides with it, and the region AGH is the curved corner” is a product by process limitation. Even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process, see MPEP 2113.
(b) Regarding claim 2:
(i) The admitted prior art as modified by Suzuki teaches the centrifugal impeller of claim 1.
(ii) Suzuki further teaches:
wherein the outlet edge comprises a vertex A (corner between rear edge and the tip of the blade, Fig 2) and a point G (point β, Fig 2);
the blade top comprises a point H (point α, Fig 2);
the vertex A and the point G are connected to form a first curve AG (line between vertex and point β, Fig 2);
the vertex A and the point H are connected to form a second curve AH (line between vertex and point α, Fig 2);
the point G and the point H are connected to form a third curve GH (line C, Fig 2);
the curved corner is formed on each of the plurality of vanes by the first curve AG, the second curve AH, and the third curve GH (Fig 2); and
a length of the first curve AG (length B’ which is a length between point β and the tip of the blade, Fig 2) is less than or equal to half of a length of the outlet edge (B’ has a length between 1/10 length B to 1/2 length B, Col 2 Lns 61-63).
Conclusion
Applicant's amendment 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 reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply 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 nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Justin A Pruitt whose telephone number is (571)272-8383. The examiner can normally be reached T-F 8:30am - 6:30pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nathaniel 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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/JUSTIN A PRUITT/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745