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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 6/3/2026 has been entered.
Response to Arguments
Applicant's arguments filed 5/12/26 have been fully considered but they are not persuasive.
Applicant asserts that:
“Claim 1 has been amended herein to recite wherein each second portion comprises a respective pole face, and the pole faces of the first and second arms are asymmetric and concaved, and a centre of curvature of the pole face of the first arm is different to a centre of curvature of the pole face of the second arm such that the pole faces have different curvatures. These features relate in part to claims 6 and 7. For the reasons presented herein, Applicant contends that amended claim 1 is allowable over the prior art.”
The examiner disagrees.
As to claim 1, Chen discloses a stator core, the stator core comprising a back, and first and second arms extending from the back, each of the first and second arms comprising a first portion extending substantially orthogonally relative to the back, and a second portion obliquely angled relative to the first portion, wherein the back and the first and second arms define a winding channel for locating a winding relative to the stator core (125; Fig. 2), and the winding channel comprises a generally trapezoidal cross-sectional shape (Fig. 2).
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Chen fails to disclose a brushless permanent magnet motor, and wherein each second portion comprises a respective pole face, and the pole faces of the first and second arms are asymmetric and concaved, and a centre of curvature of the pole face of the first arm is different to a centre of curvature of the pole face of the second arm such that the pole faces have different curvatures.
Yu, however, discloses a brushless permanent magnet motor (“The permanent magnet motor 100 is a single-phase brushless permanent magnet motor”).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the stator core of Chen with a brushless permanent magnet motor, as disclosed by Yu, to achieve higher levels of efficiency and to reduce the size of the motor.
Dymond, however discloses each second portion comprises a respective pole face, and the pole faces of the first and second arms are asymmetric and concaved (Fig. 5; Para 0026), and a centre of curvature of the pole face of the first arm is different to a centre of curvature of the pole face of the second arm such that the pole faces have different curvatures (Fig. 5).
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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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-2, 4, 8-10, 13, and 20-22 are rejected under 35 U.S.C. 103 as being unpatentable over Chen (CN 211630057), and in view of Yu (GB 2577546), and Dymond (US 20170170693).
As to claim 1, Chen discloses a stator core, the stator core comprising a back, and first and second arms extending from the back, each of the first and second arms comprising a first portion extending substantially orthogonally relative to the back, and a second portion obliquely angled relative to the first portion, wherein the back and the first and second arms define a winding channel for locating a winding relative to the stator core (125; Fig. 2), and the winding channel comprises a generally trapezoidal cross-sectional shape (Fig. 2).
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Chen fails to disclose a brushless permanent magnet motor, and wherein each second portion comprises a respective pole face, and the pole faces of the first and second arms are asymmetric and concaved, and a centre of curvature of the pole face of the first arm is different to a centre of curvature of the pole face of the second arm such that the pole faces have different curvatures.
Yu, however, discloses a brushless permanent magnet motor (“The permanent magnet motor 100 is a single-phase brushless permanent magnet motor”).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the stator core of Chen with a brushless permanent magnet motor, as disclosed by Yu, to achieve higher levels of efficiency and to reduce the size of the motor.
Dymond, however discloses each second portion comprises a respective pole face, and the pole faces of the first and second arms are asymmetric and concaved (Fig. 5; Para 0026), and a centre of curvature of the pole face of the first arm is different to a centre of curvature of the pole face of the second arm such that the pole faces have different curvatures (Fig. 5).
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the stator core of Chen with each second portion comprises a respective pole face, and the pole faces of the first and second arms are asymmetric and concaved, and a centre of curvature of the pole face of the first arm is different to a centre of curvature of the pole face of the second arm such that the pole faces have different curvatures, as disclosed by Dymond, in order to increase saliency (Para 0026 of Dymond).
As to claim 2, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in Claim 1, wherein the second portions of the first and second arms are angled toward one another (Fig. 6 of Chen).
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As to claim 4, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in claim 1, wherein the second portions of the first and second arms are angled (Fig. 2 of Chen). Chen fails to disclose around 20 to 40 degrees relative to the respective first portions of the first and second arms.
However, those skilled in the art would recognize that the above limitations do not involve any inventive concept. They would merely depend on how one decides to design the angle of the first and second arms. Furthermore, the instant specification fails to disclose any unexpected results obtained from the fact that the second portions of the first and second arms are angled around 20 to 40 degrees relative to the respective first portions of the first and second arms.
Therefore, it would have been obvious to one having ordinary skill in the art before the
effective filing date of the claimed invention to have modify the stator core of Chen, such that the second portions of the first and second arms are angled around 20 to 40 degrees relative to the respective first portions of the first and second arms, in order to reduce the volume and make the structure compact.
As to claim 8, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in claim 1, wherein the pole faces of the first and the second arms are asymmetric such that the pole face of the first arm is a different shape to the pole face of the second arm (Fig. 5; Para 0026 Dymond), the pole face of the first arm is asymmetric about a centre line of the pole face of the first arm (Fig. 5; Para 0026 Dymond), and the pole face of the second arm is asymmetric about a centre line of the pole face of the second arm (Fig. 5; Para 0026 Dymond).
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As to claim 9, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in Claim 8, wherein the pole faces of the first and second arms are spaced apart to define a slot gap (Fig. 2 of Chen).
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Chen fails to disclose a ratio of a combined width of the pole faces to the width of the slot gap is in the region of 3:1 to 7:1.
However, those skilled in the art would recognize that the above limitations do not involve any inventive concept. They would merely depend on how large one decides to design the slot gap. Furthermore, the instant specification fails to disclose any unexpected results obtained from the fact that a ratio of a combined width of the pole faces to the width of the slot gap is in the region of 3:1 to 7:1.
Therefore, it would have been obvious to one having ordinary skill in the art before the
effective filing date of the claimed invention to have modify the stator core of Chen, such that a ratio of a combined width of the pole faces to the width of the slot gap is in the region of 3:1 to 7:1, in order to optimize space for the windings.
As to claim 10, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in claim 9, wherein a distance from the pole face of the first arm to a centre line of the slot gap is different to a distance from the pole face of the second arm to the centre line of the slot gap (Fig. 5; Para 0026 Dymond), the asymmetry of the pole faces providing saliency to the pole faces (Para 0026 Dymond).
As to claim 13, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in claim 1, wherein the back is asymmetric about a centre line of the stator core (Fig. 5 Dymond).
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As to claim 20, the combination of Chen, Yu, and Dymond discloses a brushless permanent magnet motor comprising the stator core as claimed in claim 1 (Yu states, “The permanent magnet motor 100 is a single-phase brushless permanent magnet motor”).
As to claim 21, the combination of Chen, Yu, and Dymond discloses a vacuum cleaner (Fig. 13 of Yu) comprising the brushless permanent magnet motor as claimed in claim 20.
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As to claim 22, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in claim 9, wherein a distance from the centre of curvature of the pole face of the first arm to the centre line of the slot gap is different from a distance from the centre of curvature of the pole face of the second arm to the centre line of the slot gap (Fig. 5 Dymond), the asymmetry of the pole faces providing saliency to the pole faces (Para 0026 of Dymond).
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Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Chen, Yu, Dymond, and in view of Weng (CN 110556997)
As to claim 5, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in Claim 1.
Chen fails to disclose a length of each second portion is in the region of 1.5 to 2.5 times a length of the respective first portion.
Weng, however, discloses a length of each second portion is larger than the length of the first portion (Fig. 7b).
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Weng fails to disclose in the region of 1.5 to 2.5 times a length of the respective first portion.
However, those skilled in the art would recognize that the above limitations do not involve any inventive concept. They would merely depend on how one decides how much longer the second portion is than the first portion. Furthermore, the instant specification fails to disclose any unexpected results obtained from the fact a length of each second portion is in the region of 1.5 to 2.5 times a length of the respective first portion.
Therefore, it would have been obvious to one having ordinary skill in the art before the
effective filing date of the claimed invention to have modify the stator core of Chen, such that a length of each second portion is in the region of 1.5 to 2.5 times a length of the respective first portion, in order to optimize space for the windings.
Claims 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over Chen, Yu, Dymond, and in view of Gary (GB 2500580).
As to claim 11, the combination of Chen, Yu, and Dymond discloses the stator core as claimed in Claim 1.
Chen fails to disclose the stator core comprises a plurality of laminations connected together, and the second portions of the first and second arms comprise protrusions for facilitating connection of the plurality of laminations.
Gary, however, discloses the stator core comprises a plurality of laminations connected together, and the second portions of the first and second arms comprise protrusions for facilitating connection of the plurality of laminations (Fig. 1).
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the stator core of Chen with the stator core comprises a plurality of laminations connected together, and the second portions of the first and second arms comprise protrusions for facilitating connection of the plurality of laminations, as disclosed by Gary, to properly secure the lamination together.
As to claim 12, the combination of Chen, Yu, Dymond, and Gary discloses the stator core as claimed in Claim 11, wherein the protrusions are located on outwardly facing surfaces of the second portions (Fig. 1 Gary).
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Claims 14-15 are rejected under 35 U.S.C. 103 as being unpatentable over Chen, Yu, Dymond, and in view of Thomas (GB 2571553).
As to claim 14, the combination of Chen, Yu, and Dymond discloses a stator core as claimed in Claim 1.
Chen fails to disclose the stator core sub-assembly, and a bobbin overmoulded to the stator core.
Thomas, however, discloses the stator core sub-assembly (Fig. 5), and a bobbin (54, 56; Fig. 3) overmoulded to the stator core.
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the stator core of Chen with the stator core sub-assembly, and a bobbin overmoulded to the stator core, as disclosed by Thomas, to properly insulate the stator core.
As to claim 15, the combination of Chen, Yu, Dymond, and Thomas discloses the stator core sub-assembly as claimed in Claim 14, wherein the bobbin comprises a winding guide for guiding a winding relative to the bobbin (44; Fig. 9 of Yu), the winding guide located within a channel on a portion of the bobbin that overlies the back of the stator core (Fig. 9 of Yu).
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Claims 16-19 are rejected under 35 U.S.C. 103 as being unpatentable over Chen, Yu, Dymond, Thomas, and in view of Kim (US 20140009022).
As to claim 16, the combination of Chen, Yu, Dymond, and Thomas discloses the stator core sub-assembly as claimed in Claim 14.
Chen fails to disclose wherein the bobbin comprises a connection portion for connecting to a further bobbin of a further stator core sub-assembly.
Kim, however, discloses the bobbin comprises a connection portion (45; Fig. 6) for connecting to a further bobbin of a further stator core sub-assembly (Para 0082).
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Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to provide the subassembly of Chen with the bobbin comprises a connection portion for connecting to a further bobbin of a further stator core sub-assembly, as disclosed by Kim, in order to properly secure the bobbins together.
As to claim 17, the combination of Chen, Yu, Dymond, and Thomas discloses the stator core sub-assembly as claimed in claim 14, wherein the stator core sub-assembly comprises a winding wound about the bobbin such that the winding is wound about the back of the stator core (Fig. 5 of Thomas), and the winding defines a generally trapezoidal cross-sectional shape on an inner surface of the back (Fig. 2 of Chen).
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As to claim 18, the combination of Chen, Yu, Dymond, and Thomas discloses the stator core sub-assembly as claimed in claim 17, wherein the winding defines a different cross-sectional shape on an outer surface of the back (Fig. 9 of Yu).
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As to claim 19, the combination of Chen, Yu, Dymond, and Thomas discloses a stator assembly (Fig. 5 of Thomas) comprising a plurality of the stator core sub-assemblies as claimed in Claim 14.
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Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ETHAN N VO whose telephone number is (571)270-7593. The examiner can normally be reached Mon-Fri 8:30am - 5pm.
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/ETHAN NGUYEN VO/
Examiner, Art Unit 2834
/CHRISTOPHER M KOEHLER/Supervisory Patent Examiner, Art Unit 2834
Prosecution Insights