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 .
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 1-9 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the limitation " A high-speed BLDC motor with a stable bearing structure, comprising a stator assembly, a rotor assembly, a rotating shaft, a bearing member and a shaft sleeve, wherein the bearing member comprises a first bearing and a second bearing, " in lines 1-3. There is insufficient antecedent basis for this limitation in the claim. It is unclear how can a singular bearing member comprises a plurality of bearings. The bearings themselves are separate entities and not bonded to each other to form a singular bearing member in neither the prior art nor in Applicant’s disclosure. A clearer disclosure of bearing members would enhance clarity. Appropriate correction is required.
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 1-2, 5 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Kim (US2022209620A1) in view of Li (US2017149304A1).
Claim 1
A high-speed BLDC motor (100) with a stable bearing structure, comprising a stator assembly (250), a rotor assembly (300), a rotating shaft (301), a bearing member (351, 352) and a spacer (353), wherein the bearing member (351, 352) comprises a first bearing (351) and a second bearing (352), the first bearing (351) comprises a first bearing inner ring (355) and a first bearing outer ring (354), the second bearing (352) comprises a second bearing inner ring (355) and a second bearing outer ring (354), wherein two end faces of the spacer (353) are in contact with end faces of the first bearing inner ring (355) and the second bearing inner ring (355) respectively.
PNG
media_image1.png
860
528
media_image1.png
Greyscale
Kim is silent to the BLDC motor comprising a shaft sleeve, wherein two end faces of the shaft sleeve are in contact with end faces of the first bearing inner ring and the second bearing inner ring respectively.
Li conversely teaches a BLDC motor comprising a stable bearing structure, a rotating shaft (351), a first bearing (353), a second bearing (353), and a shaft sleeve (55), wherein two (axial) end faces of the shaft sleeve (55) are in contact with end faces of the first bearings inner ring and the second bearings inner ring respectively.
PNG
media_image2.png
964
660
media_image2.png
Greyscale
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 Kim’s BLDC motor to incorporate a shaft sleeve in place of Kim’s spacer, wherein two end faces of the shaft sleeve are in contact with end faces of the first bearing inner ring and the second bearing inner ring respectively. Incorporating a shaft sleeve to Kim’s BLDC motor would be advantageous as the sleeve serves as a replaceable, sacrificial surface that protects the original shaft from wear, corrosion, and erosion, thereby extending the shafts lifespan and significantly reducing maintenance costs and downtime.
Claim 2/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 1, wherein the first bearing (351) and the second bearing (352) are provided on the same side of the rotor assembly (300).
Claim 5/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 1, wherein the bearing member (351, 352) is provided in a bearing chamber (chamber within inner and outer bearing rings), and the bearing chamber (chamber within inner and outer bearing rings) is provided with a boss (2007) for applying a support force to the bearing member (351, 352).
Claim 7/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 1, further comprising a housing (110), wherein an end face of the housing (110) is provided with ventilation grooves (220).
Claims 3 is rejected under 35 U.S.C. 103 as being unpatentable over Kim as modified by Li in view of Chen (US 11221045 B2).
Claim 3/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 1, but is silent to: wherein the first bearing outer ring has a displacement of 0.01-0.015 mm relative to the first bearing inner ring, and the second bearing outer ring has a displacement of 0.01-0.015 mm relative to the second bearing inner ring.
Chen conversely teaches a bearing assembly comprised of an inner ring (3) and outer ring (1) with a radial clearance that is greater than or equal to 0.01 mm but less than or equal to 0.09 mm (claim 1).
PNG
media_image3.png
486
440
media_image3.png
Greyscale
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 Kim’s BLDC motor such that the first bearing outer ring has a displacement of 0.01-0.015 mm relative to the first bearing inner ring, and the second bearing outer ring has a displacement of 0.01-0.015 mm relative to the second bearing inner ring. Setting the radial bearing clearance to this tighter than normal range would reduce noise, enhance running accuracy, and increase bearing stiffness.
Claims 4 is rejected under 35 U.S.C. 103 as being unpatentable over Kim as modified by Li and Chen in view of NSK Global (see attached reference).
Claim 4/3/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 3, but is silent to: wherein a distance between the first bearing outer ring and the second bearing outer ring is 0.02-0.03 mm shorter than a distance between the first bearing inner ring and the second bearing inner ring.
NSK Global conversely discloses a method of designing bearings based on their internal clearance. According to NSK Global, internal clearance is measure of a distance which two rings (inner and outer bearing rings) of a non-installed bearing can move when they are pushed in opposite directions. The axial displacement between the two rings is defined by the bearing’s axial clearance. The axial clearance of a bearing is a means effective variable of the radial clearance of the bearing as evident by NSK Global’s equation for determining axial clearance.
A
x
i
a
l
c
l
e
a
r
a
n
c
e
δ
a
=
δ
r
cot
a
≅
1.5
e
δ
r
Where
δ
r
is the radial clearance, a is the contact angle, and e is a constant. Noting Chen’s teaching of a bearing clearance optimized for a range between 0.01mm-0.09mm, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used Chen’s radial clearance in order to modify Kim’s axial clearance to an optimal value within the range of 0.02-0.03mm. Considering both the first and second bearings have the same radial clearances and their axial positions relative to one another is unchanged, by optimizing the axial clearance of one of the bearings to fall within the range of 0.02-0.03mm, the axial distance between the first bearing outer ring and the second bearing outer ring may be 0.02-0.03 mm shorter than a distance between the first bearing inner ring and the second bearing inner ring. Optimizing the axial clearance of the individual bearings and therefore optimizing the axial distance between the respective inner and outer rings of each bearing relative to one another would prove advantageous as it would offer an ideal clearance, or end play that would ensure the motor’s performance, reliability, and longevity.
Claims 6 is rejected under 35 U.S.C. 103 as being unpatentable over Kim as modified by Li in view of Jiang (US 20160043620 A1).
Claim 6/5/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 5, but is silent to: wherein the boss has a thickness of 0.2-1 mm.
Jiang conversely teaches a method for making a BLDC motor with an optional housing thickness form 0.1 to 0.3mm. Considering Kim’s boss (2007) is integral with the housing and made of the same material, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used Jiang’s method to modify Kim’s boss to have a thickness of 0.2-1 mm.
Claims 8 is rejected under 35 U.S.C. 103 as being unpatentable over Kim as modified by Li in view of Shiraki (US10454328B2).
Claim 8/7/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 7, but is silent to: wherein each of the ventilation grooves has a diameter of 1-5 mm.
Shiraki conversely teaches an electric motor and a method of making ventilation grooves (Hr), wherein the ventilation grooves (Hr) have a diameter of 3mm (para. 0077). Considering Kim’s also uses ventilation grooves, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have used Shiraki’s method to modify Kim’s ventilation grooves to have a diameter of 1-5 mm.
Claims 9 is rejected under 35 U.S.C. 103 as being unpatentable over Kim as modified by Li in view of Ueda (US 20090034889 A1).
Claim 9/1
The high-speed BLDC motor (100) with a stable bearing structure according to claim 1, but is silent to: wherein the shaft sleeve is made of metal.
Ueda conversely teaches a dynamic bearing motor comprised of a shaft (2) and a shaft sleeve (4) both manufactured from stainless steel material (para. 0022).
PNG
media_image4.png
828
310
media_image4.png
Greyscale
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 Kim’s shaft sleeve such that it was made of metal. The advantage of manufacturing a shaft sleeve with a metal such as the stainless-steel material used by Ueda is advantageous as stainless steel for instance is corrosion resistant, and has high strength and durability
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AHMED F SECK whose telephone number is (571)272-4638. The examiner can normally be reached Monday - Friday 7:30 am - 4:30 pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Christopher Koehler can be reached at (571) 272-3560. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/AHMED F SECK/Examiner, Art Unit 2834
/CHRISTOPHER M KOEHLER/Supervisory Patent Examiner, Art Unit 2834