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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Response to Amendment
Rejections and objections not repeated herein are withdrawn.
Claim Interpretation
No claim limitations are interpreted under 112(f).
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.
Claims 1, 3-5, 9, 11-15, 17, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Bähren (US 2015/0071782) in view of Kollipara (WO 2024191847).
Regarding claim 1, Bähren discloses:
An impeller of a radial fan for conveying a gaseous fluid (¶2), the impeller comprising:
a bottom plate (3, see Fig 1),
a cover plate (7, see Fig 1),
wherein the cover plate is spaced apart from the bottom plate in an axial direction (along axis 2 in Fig 1) of the impeller,
wherein at least one of the cover plate (¶57, Fig 14, cover plate and bottom plate, Fig 16 shows beads at both ends of the blade) or the bottom plate (¶56 Fig 13, bottom plate only, see Fig 16) has at least one impressed bead (55 or 69 or 85, ¶56 “the beads 55 are impressed,” ¶59 “the beads 85 are impressed”),
a plurality of blades (52 or 62 or 82),
wherein at least one blade, of the plurality of blades, is arranged between the cover plate and the bottom plate and is fastened in a region of and over a profile of the at least one impressed bead (Figs 13, 14, and 16, ¶56-¶57),
wherein the at least one blade, of the plurality of blades, has a first blade surface facing a radially outward direction (outer, convex side of the blade), a second blade surface facing a radially inward direction (inner, concave side of the blade), a radially outward edge (9, see Fig 2, ¶45) extending in the axial direction, and a radially inward edge (8) extending in the axial direction,
wherein the first blade surface and the second blade surface extend from the radially inward edge to the radially outward edge (see Figs),
…
wherein a surface profile of the at least one impressed bead follows a surface profile of the at least one blade (Figs 13, shape of 52 and 55; Fig 14, shape of 52 and 68/69; ¶56, “their curve path are matched to the curvature of the blades 52,” ¶59 “in the aerodynamically effective flow space bounded by the blades 82, the round sheet-metal blank 83 and the ring 87, an advantageous aerodynamic effect is produced by the beads 85”) fastened to the at least one impressed bead (¶56, ¶57 “welding”), at least in an envelope, such that a conveying effect of the at least one impressed bead transitions, at least, to a conveying effect of the second blade surface of the at least one blade (¶59 “the beads 85 are impressed into the round sheet-metal blank 83 in the direction of the blades 82 so that, in the aerodynamically effective flow space bounded by the blades 82, the round sheet-metal blank 83 and the ring 87, an advantageous aerodynamic effect is produced by the beads 85.” Because the impressed beads have a corresponding airfoil shape and protrude away from the bottom and/or cover plate and in the direction of the blade, they have at least a partially axially extending surface that contributes to the conveying effect.).
The drawings of Bähren lack shading, so we must rely on other evidence to establish that the impressed bead goes toward the blade. First, ¶56 states “the beads 55 are impressed in the round sheet-metal blank 53 in the direction of the blades 52.” ¶56 also states, “the beads 55 permit welding of the axial end sections of the 52 to the round sheet-metal blank 53, without this causing the weld bead resulting from the welding operation to protrude above the round sheet-metal blank surface 56.” Note in Fig 13 that 56 is on the left side, on the side facing away from the blades. Likewise in reference to Fig 16, ¶59 states “the beads 85 are impressed into the round sheet-metal blank 83 in the direction of the blades 82.”
Bähren does not disclose:
the radially outward edge has a curved profile.
Kollipara teaches:
a radial fan for conveying a gaseous fluid (¶3) wherein “the trailing edge 134 is provided with a concave asymmetric curved shape, which can generally serve to reduce expansion losses. Testing has shown that in some implementations, a trailing edge 134 having an asymmetric curvature aids in the separation of flow at the wheel back 104 and the uniform distribution of pressure across the blade span (e.g., from the inlet wheel 102 to the wheel back 104), resulting in a quieter, more energy efficient flow of air through the centrifugal fan 100” (¶83).
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COMBINATION
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 radial flow fan of Bähren by forming the radially outward edge, i.e., the trailing edge with an asymmetric curved profile, as taught by Kollipara, to obtain the benefit of quieter, more energy efficient flow of air through the fan.
Regarding claim 14, Bähren modified by the curved outer edge of Kollipara as described above with reference to claim 1 and for the same reasons, teaches:
A radial fan comprising an impeller (with continued reference to Bähren, except as noted: 1, see Fig 1, 61, see Fig 14, 81, see Fig 16) for conveying a gaseous fluid, wherein the impeller comprises:
a bottom plate (3 in Fig 1),
a cover plate (7, see Fig 1),
wherein the cover plate is spaced apart from the bottom plate in an axial direction (along axis 2 in Fig 1) of the impeller,
wherein at least one of the cover plate (¶57, Fig 14, cover plate and bottom plate, Fig 16 shows beads at both ends of the blade) or the bottom plate (¶56 Fig 13, bottom plate only, see Fig 16) has at least one impressed bead (55 or 69 or 85, ¶56 “the beads 55 are impressed,” ¶59 “the beads 85 are impressed”),
a plurality of blades (52 or 62 or 82),
wherein at least one blade, of the plurality of blades, is arranged between the cover plate and the bottom plate and is fastened in a region of and over a profile of the at least one impressed bead (Figs 13, 14, and 16, ¶56-¶57),
wherein the at least one blade, of the plurality of blades, has a first blade surface facing a radially outward direction (outer, convex side of the blade), a second blade surface facing a radially inward direction (inner, concave side of the blade), a radially outward edge (9, see Fig 2, ¶45) extending in the axial direction, and a radially inward edge (8) extending in the axial direction,
wherein the first blade surface and the second blade surface extend from the radially inward edge to the radially outward edge (see Figs),
wherein the radially outward edge has a curved profile (as taught by Kollipara),
wherein a surface profile of the at least one impressed bead follows a surface profile of the at least one blade (Figs 13, shape of 52 and 55; Fig 14, shape of 52 and 68/69; ¶56, “their curve path are matched to the curvature of the blades 52,” ¶59 “in the aerodynamically effective flow space bounded by the blades 82, the round sheet-metal blank 83 and the ring 87, an advantageous aerodynamic effect is produced by the beads 85”) fastened to the at least one impressed bead, at least in an envelope, such that a conveying effect of the at least one impressed bead transitions at least, to a conveying effect of the second blade surface of the at least one blade (¶59 “the beads 85 are impressed into the round sheet-metal blank 83 in the direction of the blades 82 so that, in the aerodynamically effective flow space bounded by the blades 82, the round sheet-metal blank 83 and the ring 87, an advantageous aerodynamic effect is produced by the beads 85.” Because the impressed beads have a corresponding airfoil shape and protrude away from the bottom and/or cover plate and in the direction of the blade, they have at least a partially axially extending surface that contributes to the conveying effect.).
Regarding claim 3, Bähren and Kollipara teach:
the first blade surface (outer, convex side of the blade) is opposite the second blade surface (inner, concave side of the blade).
Regarding claim 4, Bähren and Kollipara teach:
the curved profile of the radially outward edge forms an arc relative to the axial direction (see Kollipara Fig 33).
Regarding claim 5, Bähren and Kollipara teach:
the curved profile of the radially outward edge is a convex profile relative to the axial direction (see Kollipara Fig 33).
Regarding claim 9, Bähren and Kollipara teach:
the at least one impressed bead has a pressure-side contour profile, which deviates from a suction-side contour profile of the at least one impressed bead (Fig 16, ¶59 “a radially outer zone with greater width”).
Regarding claim 11, Bähren and Kollipara teach:
a fastening of the at least one blade is formed by a welded (¶56, ¶57) connection, or…[alternative limitations]… wherein the fastening is arranged on a pressure side and/or on a suction side of the at least one blade (as shown in the detail of Fig 5, the available places for welding are on the pressure or suction side of the blade because that is where there is adjacent disk material to weld to. Note that the bead 55 provides a recess which allows the weld to made without protruding from the surface 56.).
Regarding claim 12, Bähren and Kollipara teach:
the fastening is formed in multiple parts, wherein either at least a first part of the fastening is formed between the at least one blade and the bottom plate (¶15 “material bonding” fills the bead between the blade, the weld, and the surface of the disc, and thus connects the blade end to the disk) and at least a second part of the fastening is formed between the at least one blade and the at least one impressed bead (the weld described in ¶56, ¶57), or at least a first part of the fastening is formed between the at least one blade and the cover plate and at least a second part of the fastening is formed between the at least one blade and the at least one impressed bead.
Regarding claim 13, Bähren and Kollipara teach:
the at least one blade is arranged between a pair of impressed beads,
wherein the pair of impressed beads includes the at least one impressed bead,
wherein the pair of impressed beads includes, as the at least one impressed bead, a first impressed bead,
wherein the pair of impressed beads comprises a second impressed bead, wherein the first impressed bead is formed on the cover plate and the second impressed bead is formed on the bottom plate (¶57, “the ring 67 is also provided with recesses 68… the recesses 68 are each located at the base of a bead 69;” ¶59/Fig 16 “more additional beads are provided in the round sheet-metal blank and/or ring”), and
wherein the radially outward edge extends in the axial direction between the first impressed bead and the second impressed bead (see Fig 16, the outward edge is in the region of the beads).
Regarding claim 15, Bähren and Kollipara teach:
the at least one of the cover plate or the bottom plate comprises a plurality of impressed beads (see Figures of Bähren, with beads for each blade), and wherein the at least one impressed bead is one of the plurality of impressed beads.
Regarding claim 17, Bähren and Kollipara teach:
a flank of the at least one impressed bead is formed along a contour of the at least one blade (Figs 13, 14, and 16, particularly the alignment between 52 and 55 in Fig 13).
Regarding claim 20, Bähren and Kollipara teach:
the at least one of the cover plate or the bottom plate comprises a plurality of impressed beads (¶57, ¶59: one at each junction between a blade and the disk and/or cover), and wherein the at least one impressed beads in one of the plurality of impressed beads.
Claims 6-8, 16, and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Bähren (US 2015/0071782) in view of Kollipara (WO 2024191847) as applied to claims 1 and 14, and further in view of Japikse (US 2014/0205458).
Regarding claim 6, Bähren and Kollipara do not teach:
a height of the at least one impressed bead is at most a sixth of a distance between the bottom plate and the cover plate.
Regarding claim 7, Bähren and Kollipara do not teach:
a height of the at least one impressed bead is at most one eighth of a distance between the bottom plate and the cover plate.
Regarding claim 8, Bähren and Kollipara do not teach:
a height of the at least one impressed bead is at most one tenth of a distance between the bottom plate and the cover plate.
Japikse teaches:
a shrouded impeller with blades (referred to as vanes in the text) connected to a disk and a shroud. Fillets are provided at the disk and shroud to improve blade strength and a thickness distribution to improve vibrational performance (¶44, ¶46, ¶55). Japikse explicitly teaches that the fillet radius (i.e., height and width) is a result effective variable for vibration performance. It is self-evident that the fillet radius is a result effective variable for the blade strength/stiffness.
COMBINATION
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 modified the impeller of Bähren to have a height of the impressed bead correspond to at most one tenth of the distance between the bottom plate and the cover plate to provide the desired blade strength, stiffness, and vibrational response because it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art.
Regarding claim 16, Bähren and Kollipara do not disclose:
a height of the at least one impressed bead corresponds to a twentieth of a distance between the bottom plate and the cover plate.
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 impeller of Bähren to have a height of the impressed bead correspond to a twentieth of the distance between the bottom plate and the cover plate to provide the desired blade strength, stiffness, and vibrational response because it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art.
Regarding claim 18, Bähren and Kollipara do not disclose:
the height of the at least one impressed bead is, at most, a fiftieth, of a distance between the bottom plate and the cover plate.
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 impeller of Bähren to have a height of the impressed bead correspond to a fiftieth of the distance between the bottom plate and the cover plate to provide the desired blade strength, stiffness, and vibrational response because it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art.
Claims 2, 10, and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Bähren (US 2015/0071782) in view of Kollipara (WO 2024191847) as applied to claim 1, and further in view of Lörcher (US 10,550,854).
Regarding claim 2, Bähren as modified by Kollipara does not explicitly teach:
the surface profile of the at least one impressed bead follows a surface profile of the second blade surface of the at least one blade.
Bähren does not show sufficient detail of the interface between the second blade surface and the bead. However, Bähren does disclose that “in the aerodynamically effective flow space bounded by the blades 82, the round sheet-metal blank 83 and the ring 87, an advantageous aerodynamic effect is produced by the beads 85” (¶59).
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Lörcher teaches:
a radial flow fan impeller having a rounded transition between the blade 6 and the base plate 8. The rounded transition provides that “only very low stress peaks occur in the transitional region during operation.” (col 8 line 66 – col 9 line 8).
COMBINATION
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 impeller of Bähren to have a continuously curved transition between the bead and the bottom plate and/or cover plate, as taught by Lörcher to obtain the benefit of low stress peaks. In the combination, the curved transition is formed by the impressed beads of Bähren, because that is the portion of the impeller that interfaces with the blades. Because the curved transition blends smoothly into the blades, it follows a surface profile of the blade on both sides and contributes to the conveying effect.
Regarding claim 10, Bähren modified by the curved transition of Lörcher, as described above with reference to claim 2, and for the same reasons, teaches:
a bead outlet of the at least one impressed bead, has a curved transition (as taught by Lörcher) into the bottom plate or into the cover plate.
Regarding claim 19, Bähren modified by the curved transition of Lörcher, as described above with reference to claim 2, and for the same reasons, teaches:
the at least one impressed bead has a curved transition (as taught by Lörcher) into the bottom plate or into the cover plate.
Pertinent Prior Art
Asano (US 2023/0332615) teaches a radial fan with a shape including a curved trailing edge (¶46) for “equalizing the air velocity distribution of the airflow on the outer surface 4a of the blade 4” (¶50).
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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 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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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Courtney Heinle can be reached on (571) 270-3508. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/TOPAZ L. ELLIOTT/Primary Examiner, Art Unit 3761
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