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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 08/26/2026 has been entered.
Response to Arguments
Applicant's arguments filed on 08/26/2026 have been fully considered.
With respect to claim 1, applicant argued that the applied references do not teach the amended limitations to claim 1. The examiner notes the limitations are not patentable and are addressed in a new rejection below.
With respect to new claim 18 (claim 18 includes the limitations of original claim 1, the limitations added in the previous amendment and additional limitations), the examiner notes that the additional limitations “wherein a circumferential side face of each cage bar is provided in the axial direction with at least two contact areas spaced axially apart and each configured to contact the spherical roller” are not patentable and are addressed in a rejection below.
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.
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.
Claim(s) 1-5, 7-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Honda et al. (US 5,234,274) hereinafter Honda in view of Bjorkman (US 2016/0178001 A1) and further in view of Kellstrom et al. (US 5,474,388) hereinafter Kellstrom.
Regarding claim 1, Honda teaches a spherical roller bearing for supporting a wind turbine main shaft, the spherical roller bearing comprising:
an outer ring (1) having two raceways (5 formed on the left and right side of oil supply hole in Fig. 14) (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
an inner ring (2) having two raceways (6) and a bore with a diameter (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
two sets of spherical rollers (3) which roll along the raceways formed on the outer ring and the inner ring (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
and at least one cage (4) configured to retain the spherical rollers (Figs. 9-14), the at least one cage comprising at least one axial inner cage ring (8) extending in a circumferential direction of the spherical roller bearing, a first axial outer cage ring (9) spaced from the at least one axial inner cage ring on a first axial side and connected to the at least one axial outer cage ring by a plurality of cage bars (7) (Col. 1, line 13-Col. 2, line 2; Figs. 9-14), the plurality of cage bars forming a plurality of closed pockets (10), each of the plurality of closed pockets being configured to receive one spherical roller of a first set of spherical rollers of the two sets of spherical rollers (Col. 1, line 13-Col. 2, line 2; Figs. 9-14), and a second axial outer cage ring (9) spaced from the at least one axial inner cage ring on a second axial side opposite to the first axial side and connected to the at least one axial inner cage ring by a plurality of cage bars, the plurality of cage bars forming a plurality of closed pockets (Col. 1, line 13-Col. 2, line 2; Figs. 9-14), each pocket of the plurality of closed pockets being configured to receive one spherical roller of a second set of spherical rollers of the two sets of spherical rollers (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
wherein each one of the cage bars are at least partially is entirely arranged at a position in a radial direction that is offset radially inwardly from a pitch diameter and is entirely angled radially inwardly in an axial direction from the at least one axial inner cage ring to the first axial outer cage ring or the second axial outer cage ring (Figs. 9-14).
Honda does not specifically state that the bore diameter is at least 499 mm and wherein the first axial outer cage ring and the second axial outer cage ring are each spaced radially outwardly from the inner ring such that the at least one cage is predominantly roller guided.
However, However, Bjorkman teaches a spherical roller bearing (1) for supporting a wind turbine main shaft, the spherical roller bearing comprising:
an outer ring (2) having two raceways (21, 22); an inner ring (3) having two raceways (31, 32) (para. 0044) and a bore with a diameter of at least 499 mm. Paragraph 0022 discloses that the outer diameter of the bearing could be up 600 mm or 1500 mm which means the diameter of the bore is at least 499 mm. Bjorkman also discloses; two sets of spherical rollers (4) which roll along the raceways formed on the outer ring and the inner ring; and at least one cage (para. 0044) configured to retain the rollers.
Because Bjorkman discloses that bore of the inner ring could have various ranges of bore diameter, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify Honda such the bore diameter is at least 499 mm as taught by Bjorkman in order to accommodate a desired shaft or rotor.
Honda as modified by Bjorkman fails to teach, wherein the first axial outer cage ring and the second axial outer cage ring are each spaced radially outwardly from the inner ring such that at least one cage is predominantly roller guided.
However, Kellstrom discloses a spherical roller bearing comprising an inner ring (11) and an outer ring (12), spherical rollers (14 and 15) disposed between the inner and outer rings (Fig. 4). Kellstrom further discloses a cage having a cage bar and a first axial outer cage ring and a second axial outer cage ring such that the first axial outer cage ring and the second axial outer cage ring are each spaced radially outwardly from the inner ring such that at least one cage is predominantly roller guided (Fig. 4, Col. 3, lines 16-32).
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It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to further modify Honda such that a first axial outer cage ring and a second axial outer cage ring such that the first axial outer cage ring and the second axial outer cage ring are each spaced radially outwardly from the inner ring such that at least one cage is predominantly roller guided as taught by Kellstrom in order to reduce wear.
Regarding claim 2, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the inner ring is formed without a flange for retaining and/or guiding the spherical rollers (Honda, Figs. 9-14).
Regarding claim 3, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the spherical roller bearing is not equipped with a guide ring (Honda, Figs. 9-14).
Regarding claims 4-5, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom does not appear to specifically state:
a ratio Dm/Dw of a minimal distance Dm in the circumferential direction between the raceways of two adjacent spherical rollers of at least one set of the two sets of spherical rollers to a maximal roller diameter (Dw) is no greater than 0.11;
the ratio Dm/Dw is no greater than 0.075.
However, a careful examination of the specification reveals that no criticality for the specific ratio has been shown nor any reason as to why the bearing of the applicant with the claimed ratio would operate any different than the bearing of Karlsson, and Applicant has not disclosed that this design with the specific ratio provides an advantage, is used for a particular purpose, or solves a stated problem. Hence this design for the ratio Dm/Dw is no greater than 0.11 or no greater than 0.075 is considered to be a design choice by the applicant. One of ordinary skill in the art, furthermore, would have expected the bearing of Honda, and Applicant’s invention, to perform equally well with the ratio taught by Honda or the claimed ratio, because both would perform the same function.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the application to use the claimed ratio with the bearing of Honda in order to achieve a desired dimension, shape, or configuration, as they are a matter of design choice. Such a modification would have been considered a mere design consideration which fails to patentably distinguish over the prior art.
Regarding claim 7, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the axial inner cage ring and/or at least one of the axial outer cage rings includes a flange element that extends radially inwardly or radially outwardly (Honda, Figs. 9-14); or the axial inner cage ring and at least one of the axial outer cage rings includes a radially extending flange element , wherein both flange elements extend radially inwardly or radially outwardly (Honda, Figs. 9-14); or the axial inner cage ring and at least one of the axial outer cage rings includes a radially extending flange element, wherein one flange element extends radially inwardly and the other flange element extends radially outwardly (Honda, Figs. 9-14).
Regarding claim 8, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the at least one cage is predominantly roller guided (Figs. 9-14).
Regarding claim 9, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches a shoulder clearance is larger than a radial clearance (Honda, Figs. 9-14).
Regarding claim 10, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches a circumferential side face of each cage bar is provided in the axial direction with one contact area or at least two contact areas configured to contact the spherical roller (Honda, Figs. 9-14).
Regarding claim 11, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches each cage bar is at least partially arranged at a distance from the raceway of the inner ring in a radial direction that corresponds to 10% to 40% of a diameter of the spherical roller or at a distance from the raceway of the outer ring in the radial direction that corresponds to 60% to 90% of the diameter of the spherical roller (Honda, Figs. 9-14).
Regarding claim 12, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the cage bars are arranged on a radially inner side of a pitch diameter of the bearing (Honda, Figs. 9-14).
Regarding claim 13, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the axial inner cage ring comprises a first ring element (8) and a second ring element (8) fixed to each other (Honda, Figs. 9-14).
Regarding claim 14, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the at least one cage is formed without any means for retaining at least one spherical roller in the at least one cage and/or within in a pocket of the at least one cage (Honda, Figs. 9-14).
Regarding claim 15, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Honda as modified by Bjorkman and Kellstrom further teaches the at least one cage and/or the spherical rollers are mountable into the spherical roller bearing without elastically and/or plastically deforming the at least one cage and/or without disassembling the at least one cage (Honda, Figs. 9-14).
Regarding claim 16, Honda as modified by Bjorkman and Kellstrom teaches all the claimed limitations as stated above in claim 1. Although Honda as modified by Bjorkman and Kellstrom does not teach the at least a bearing arrangement for a wind turbine main shaft comprising at least one spherical bearing, Bjorkman further discloses its bearing arrangement for a wind turbine comprising a main shaft. Since the bearing arrangement of Honda and Bjorkman are similar, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to use bearing arrangement of Honda in a wind turbine as further taught by Bjorkman in order rotatably support a wind turbine rotor shaft.
Claim 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Honda in view of Bjorkman and further in view of Silverio et al. (US 9,046,128 B2) hereinafter Silverio.
Honda teaches a spherical roller bearing for supporting a wind turbine main shaft, the spherical roller bearing comprising:
an outer ring (1) having two raceways (5 formed on the left and right side of oil supply hole in Fig. 14) (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
an inner ring (2) having two raceways (6) and a bore with a diameter (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
two sets of spherical rollers (3) which roll along the raceways formed on the outer ring and the inner ring (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
and at least one cage (4) configured to retain the spherical rollers (Figs. 9-14), the at least one cage comprising at least one axial inner cage ring (9) extending in a circumferential direction of the spherical roller bearing, a first axial outer cage ring (8) spaced from the at least one axial inner cage ring on a first axial side and connected to the at least one axial outer cage ring by a plurality of cage bars (7) (Col. 1, line 13-Col. 2, line 2; Figs. 9-14), the plurality of cage bars forming a plurality of closed pockets (10), each of the plurality of closed pockets being configured to receive one spherical roller of a first set of spherical rollers of the two sets of spherical rollers (Col. 1, line 13-Col. 2, line 2; Figs. 9-14), and a second axial outer cage ring (8) spaced from the at least one axial inner cage ring on a second axial side opposite to the first axial side and connected to the at least one axial inner cage ring by a plurality of cage bars, the plurality of cage bars forming a plurality of closed pockets (Col. 1, line 13-Col. 2, line 2; Figs. 9-14), each pocket of the plurality of closed pockets being configured to receive one spherical roller of a second set of spherical rollers of the two sets of spherical rollers (Col. 1, line 13-Col. 2, line 2; Figs. 9-14);
wherein each one of the cage bars are at least partially is entirely arranged at a position in a radial direction that is offset radially inwardly from a pitch diameter and is entirely angled radially inwardly in an axial direction from the at least one axial inner cage ring to the first axial outer cage ring or the second axial outer cage ring (Figs. 9-14).
Honda does not specifically state that the bore diameter is at least 499 mm.
However, Bjorkman teaches a spherical roller bearing (1) for supporting a wind turbine main shaft, the spherical roller bearing comprising:
an outer ring (2) having two raceways (21, 22); an inner ring (3) having two raceways (31, 32) (para. 0044) and a bore with a diameter of at least 499 mm. Paragraph 0022 discloses that the outer diameter of the bearing could be up 600 mm or 1500 mm which means the diameter of the bore is at least 499 mm. Bjorkman also discloses; two sets of spherical rollers (4) which roll along the raceways formed on the outer ring and the inner ring; and at least one cage (para. 0044) configured to retain the rollers.
Because Bjorkman discloses that bore of the inner ring could have various ranges of bore diameter, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify Honda such the bore diameter is at least 499 mm as taught by Bjorkman in order to accommodate a desired shaft or rotor.
Honda as modified by Bjorkman does not specifically disclose wherein a circumferential side face of each cage bar is provided in the axial direction with at least two contact areas spaced axially apart and each configured to contact the spherical roller.
However, Silverio discloses a spherical roller bearing comprising an inner ring (2) and an outer ring (3), spherical rollers (1A and 1B) disposed between the inner and outer rings (Fig. 1; Col. 2, lines 4-20). Silverio further discloses at one cage comprising a cage bar, wherein a circumferential side face of each cage bar is provided in the axial direction with at least two contact areas spaced axially apart and each configured to contact the spherical roller
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It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to further modify Honda such that the circumferential side face of each cage bar is provided in the axial direction with at least two contact areas spaced axially apart and each configured to contact the spherical roller as taught by Silverio as this would reduce wear between the cage bar and the spherical rollers.
Allowable Subject Matter
Claim 6 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim 6 defines over the prior art for the same reasons stated in the Office Action mailed on 09/10/2025.
Claim 17 is allowed.
Claim 17 is allowed because it contains the allowable limitations of claim 6.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MAXIME M ADJAGBE whose telephone number is (571)272-4920. The examiner can normally be reached M-F: 8-6.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, NATHANIEL E 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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/MAXIME M ADJAGBE/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745
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