DETAILED ACTION
Notice of Pre-AIA or AIA Status
This action is in response to the claims set filed 09/11/2025 following the Requirement for Restriction/Election of 06/27/2025. Claims 17 and 30 were amended. Claims 17-33 are currently pending.
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions
The election requirement due to a Lack of Unity established in the Office Action of 06/27/2025 has been withdrawn in light of the claim amendments and arguments presented by Applicant.
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
The following title is suggested: “WIND TURBINE ROTOR BLADE AND METHOD OF JOINING TWO ROTOR BLADE SEGMENTS WITH PRETENSIONED CONNECTING BOLTS”.
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 17-33 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.
Regarding Claims 17 and 30, the term “sleeve-like” in claims 17 and 30 is a relative term which renders the claim indefinite. The term “sleeve-like” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The modifying part of “-like” renders the claim indefinite since it is unclear what the metes and bounds would be for “similar to sleeve”.
Claims 18-29 and 31-33 are also rejected under 35 USC § 112(b) due to their respective dependency upon claim 17 or 30 rejected above.
Claim 29 recites the limitation "said screwing piece". There is insufficient antecedent basis for this limitation in the claim.
Claim 29 recites the limitation "the other connecting piece". There is insufficient antecedent basis for this limitation in the claim.
Claim 30 line 15 recites the limitation "the connecting bolts". There is insufficient antecedent basis for this limitation in the claim.
Claim 30 lines 18 recites the limitation "mounting sleeve-shaped pretensioning units". There is insufficient antecedent basis for this limitation in the claim. Only a singular pretensioning unit has been previously introduced.
Claim 30 lines 19-20, the limitation “wherein each pretensioning unit includes a first piece and a second piece” renders the claim indefinite since it is unclear what is meant to be introduced or meant to reference back to a previously recited limitation given that a pretensioning unit with a first piece and a second piece has already been introduced in the claim.
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.
Claim(s) 17-18, 21, 23 and 26-32 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 2017/0089324, herein referenced as Sanz, in view of US 5046906, herein referenced as Bucknell.
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Figure 5 of Sanz
Regarding Claim 17, Sanz discloses a wind turbine rotor blade (“bolted joint for a wind turbine blade” title) comprising:
first and second rotor blade segments (see blade modules 1 and 1’ in fig. 7C) having respective connection ends (see respective connection ends in fig. 8A);
a connecting bolt (see bolt 8 fig. 5) threadably engaging into said first and second connection ends (shown in fig. 5; “Screwing all the bolts 8 into the inserts 5 of the first blade module 1; Aligning the inserts of the second blade module 1′ with the bolts 8; Turning the bolts 8 to screw them into the inserts 5 of both the first and second modules 1 and 1’” in pr. 39);
a sleeve-shaped pretensioning unit (see spacer 9 fig. 5) arranged between said first and second rotor blade segments (see fig. 5) and being mounted on said connecting bolt (see figs. 6A-6B);
However, Sanz fails to anticipate said pretensioning unit including first and second pieces, said first and second pieces being sleeve-like and mutually engaged in a form fit manner by being a least partially inserted into each other;
said first and second pieces being movable relative to each other along said connecting bolt by applying a force in an axial direction of the corresponding bolt; and,
said first and second pieces being configured to be axially moved apart from each other along said connecting bolt against said respective connection ends so as to cause said connecting bolt to be preloaded.
Sanz is analogous art since it relates to the field of endeavor of wind turbine blades. Bucknell is analogous art since it relates to the problem faced by Applicant of pre-tensioning bolts.
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Figure 3 of Bucknell
Bucknell teaches of a sleeve-shaped pretensioning unit (see positioner 30 fig. 3) arranged between said first and second [segments] (see two slitting cutters 39 fig. 3) and being mounted on said connecting bolt (38 fig. 3);
said pretensioning unit including first and second pieces (see annular piston 32 and housing 31 in fig. 3; or alternatively, see housing 31 and locking sleeve 34 in fig. 3), said first and second pieces being sleeve-like (31, 34 and/or 32 in fig. 3are sleeve-like given their annular form) and mutually engaged in a form fit manner by being a least partially inserted into each other (housing 31 and annular piston 32 in fig. 3 shown to be partially inserted into each other analogously to Applicant's first and second pieces; alternatively, locking sleeve 34 and housing 31 in fig. 3 shown to be partially inserted into each other analogously to Applicant's first and second pieces);
said first and second pieces being movable relative to each other along said connecting bolt by applying a force in an axial direction of the corresponding bolt (applying a hydraulic force to creates a force in the axial direction which moves annular piston 32 relative to housing 31; alternatively, turning locking sleeve 34 would apply a force axially to move locking sleeve 34 relative to housing 31 in fig. 3); and,
said first and second pieces being configured to be axially moved apart from each other along said connecting bolt against said respective connection ends so as to cause said connecting bolt to be preloaded (outward movement of annular piston 32, or alternatively outward movement of locking sleeve 34, relative to housing 31 would lead to a preload of 38 in fig. 3). Bucknell further teaches that “the locking collar may have a collar end face engageable with a locking face formed on the cooperating piston or annular housing such that the annular housing and the piston may be locked in a selected extended relationship with minimal load relaxation during load transfer between hydraulic extension and locking” in col. 2 lines 23-28.
Therefore, it would have been obvious before the effective filing date of invention to one of ordinary skill in the art to have modified Sanz to have utilized the bolt pretensioning and spacing means disclosed by Bucknell so as to obtain the benefit of minimal load relaxation during load transfer between hydraulic extension and locking’ as taught by Bucknell.
Regarding Claim 18, the combination of Sanz and Bucknell comprises the wind turbine rotor blade of claim 17, wherein said first piece and said second piece of said pretensioning unit are coupled to each other via a thread (see housing 31 and locking sleeve 34 which are coupled via a thread in fig. 3 of Bucknell, as used to modify Sanz), and wherein said first and second piece are screwed apart from each other along said connecting bolt for preloading said connecting bolt (screwing apart locking sleeve 34 and housing 31 would create an axial force on 38 therefore preloading it in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 21, the combination of Sanz and Bucknell discloses the wind turbine rotor blade of claim 17, wherein said pretensioning unit is formed as a hydraulic nut unit (see pretensioner 30 in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 23, the combination of Sanz and Bucknell discloses the wind turbine rotor blade of claim 21, wherein said first piece and said second piece of said pretensioning unit form a hydraulic chamber (see cavity 36 formed between annular piston 32 and housing 31 in fig. 3 of Bucknell, as used to modify Sanz) fluidly connected to a hydraulic port (see grease nipple 37 in fig. 3 of Bucknell, as used to modify Sanz) of said first piece to apply hydraulic pressure on said first piece and said second piece to push said first piece and said second piece apart from each other (hydraulic pressure into internal passage 35 would fill cavity 36 and push annular piston 32 away from housing 31 in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 26, the combination of Sanz and Bucknell discloses the wind turbine rotor blade of claim 21, wherein said wind turbine rotor blade defines a longitudinal axis the hydraulic nut unit having a hydraulic nut port (see nipple 37 fig. 3 of Bucknell, as used to modify Sanz).
However, the combination fails to teach said hydraulic nut unit has a plurality of hydraulic nut ports; and, each of said hydraulic nut ports of said hydraulic nut units is arranged at an outer side with respect to said longitudinal axis of said wind turbine rotor blade.
It has been held that “mere duplication of parts has no patentable significance unless a new and unexpected result is produced”. MPEP 2144.04 §VI: B “Duplication of Parts” citing In re Harza, 274 F.2d 669, 124 USPQ 378 (CCPA 1960). Thus, it would have been similarly obvious to have modified amount of grease nipple in the combination of Sanz and Bucknell by duplicated so as to allow for multiple points of access. One of ordinary skill in the art would recognize that in this modification, it would have been obvious to have provided these plurality of ports at an outer side of the wind turbine blade so as to allow for ease of use and access. The duplication of parts providing would not be considered a new and unexpected result since this aspect would naturally flow from providing multiple ports in the combination of Sanz and Bucknell as modified above.
Regarding Claim 27, the combination of Sanz and Bucknell discloses the wind turbine rotor blade of claim 17, wherein said first or second piece of said pretensioning unit has a tool engaging section for an assembly tool (see grease nipple 35 on housing 31 in fig. 3 of Bucknell, as used to modify Sanz above; the grease nipple 35 would be for a grease gun).
Regarding Claim 28, the combination of Sanz and Bucknell discloses the wind turbine rotor blade of claim 27, wherein said tool engaging section includes a hexagonal shaped outer side or one or more boreholes (the grease nipple 35 represents a borehole for a grease gun to dispense grease there within in fig. 3 of Bucknell, as used to modify Sanz) for inserting mounting pins or mounting bolts (a pin or a bolt of a grease gun could be inserted at the nipple 35 in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 29, the combination of Sanz and Bucknell discloses the wind turbine rotor of claim 17, wherein at least one of said first and second piece of said pretensioning unit or said screwing piece includes one or more centering devices (see bore of housing 31 where shaft 38 is provided in fig. 3 of Bucknell, as used to modify Sanz) for centering at least one of said first and second pieces along said connecting bolt with respect to the other connecting piece and/or the adjacent connection end (the bore of housing 31 centers it along the shaft 38 in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 30, Sanz discloses a method of joining two rotor blade segments (see blade modules 1 and 1’ in fig. 7C) of a wind turbine rotor blade (“bolted joint for a wind turbine blade” title), the rotor blade segments having respective connection ends (see respective connection ends in fig. 8A), the wind turbine rotor blade including
a connecting bolt (see bolt 8 fig. 5) threadably engaging into said first and second connection ends (shown in fig. 5; “Screwing all the bolts 8 into the inserts 5 of the first blade module 1; Aligning the inserts of the second blade module 1′ with the bolts 8; Turning the bolts 8 to screw them into the inserts 5 of both the first and second modules 1 and 1’” in pr. 39);
a sleeve-shaped pretensioning unit (see spacer 9 fig. 5) arranged between said first and second rotor blade segments (see fig. 5) and being mounted on said connecting bolt (see figs. 6A-6B);
However, Sanz fails to anticipate said pretensioning unit including first and second piece¸ the first and second pieces being sleeve-like and mutually engaged in a form fit manner by being at least partially inserted into each other;
said first and second pieces being movable relative to each other along said connecting bolt by applying a force in an axial direction of the corresponding connecting bolt; and,
said first and second pieces being configured to be axially moved apart from each other along said connecting bolt against said respective connection ends so as to cause said connecting bolt to be preloaded,
the method comprising the steps:
partially screwing the connecting bolts into the first connection end of the first rotor blade segment in such a way that the connecting bolts project from the first connection end;
mounting sleeve-shaped pretensioning units to the connecting bolts to be arranged between the rotor blade segments, wherein each pretensioning unit includes a first piece and a second piece, wherein the first piece and the second piece can be moved relative to each other along the corresponding connecting bolt, and wherein the first piece and the second piece engage each other in a form fit manner;
bringing the second connection end of the second rotor blade segment close to the first connection end of the first rotor blade segment;
partially screwing the connecting bolts into the second connection end; providing an axially directed force between the first pieces and second pieces of each pretensioning unit;
axially pushing the first pieces and the second pieces of each pretensioning unit apart from each other along the corresponding connecting bolts against the respective connection ends, such that the corresponding connecting bolts are preloaded.
Sanz is analogous art since it relates to the field of endeavor of wind turbine blades. Bucknell is analogous art since it relates to the problem faced by Applicant of pre-tensioning bolts.
Bucknell teaches of a sleeve-shaped pretensioning unit (see positioner 30 fig. 3) arranged between said first and second [segments] (see two slitting cutters 39 fig. 3) and being mounted on said connecting bolt (38 fig. 3);
said pretensioning unit including first and second pieces (see annular piston 32 and housing 31 in fig. 3; or alternatively, see housing 31 and locking sleeve 34 in fig. 3), said first and second pieces being sleeve-like (31, 34 and/or 32 in fig. 3are sleeve-like given their annular form) and mutually engaged in a form fit manner by being a least partially inserted into each other (housing 31 and annular piston 32 in fig. 3 shown to be partially inserted into each other analogously to Applicant's first and second pieces; alternatively, locking sleeve 34 and housing 31 in fig. 3 shown to be partially inserted into each other analogously to Applicant's first and second pieces);
said first and second pieces being movable relative to each other along said connecting bolt by applying a force in an axial direction of the corresponding bolt (applying a hydraulic force to creates a force in the axial direction which moves annular piston 32 relative to housing 31; alternatively, turning locking sleeve 34 would apply a force axially to move locking sleeve 34 relative to housing 31 in fig. 3); and,
said first and second pieces being configured to be axially moved apart from each other along said connecting bolt against said respective connection ends so as to cause said connecting bolt to be preloaded (outward movement of annular piston 32, or alternatively outward movement of locking sleeve 34, relative to housing 31 would lead to a preload of 38 in fig. 3); the method comprises the steps: mounting sleeve-shaped pretensioning units to the connecting bolts (see positioner 30 on shaft 38 in fig. 3) to be arranged between the [segments] (see two 39 in fig. 3), wherein each pretensioning unit includes a first piece and a second piece (see annular piston 32 and housing 31 in fig. 3; or alternatively, see housing 31 and locking sleeve 34 in fig. 3), wherein the first piece and the second piece can be moved relative to each other along the corresponding connecting bolt, and wherein the first piece and the second piece engage each other in a form fit manner (applying a hydraulic force to creates a force in the axial direction which moves annular piston 32 relative to housing 31; alternatively, turning locking sleeve 34 would apply a force axially to move locking sleeve 34 relative to housing 31 in fig. 3);
Bucknell further teaches that “the locking collar may have a collar end face engageable with a locking face formed on the cooperating piston or annular housing such that the annular housing and the piston may be locked in a selected extended relationship with minimal load relaxation during load transfer between hydraulic extension and locking” in col. 2 lines 23-28.
Therefore, it would have been obvious before the effective filing date of invention to one of ordinary skill in the art to have modified Sanz to have utilized the bolt pretensioning and spacing means disclosed by Bucknell so as to obtain the benefit of minimal load relaxation during load transfer between hydraulic extension and locking’ as taught by Bucknell.
In the combination of above, the method would comprise the steps:
partially screwing the connecting bolts into the first connection end of the first rotor blade segment in such a way that the connecting bolts project from the first connection end (see bolt sticking out from the first connection end in fig. 5 of Sanz);
bringing the second connection end of the second rotor blade segment close to the first connection end of the first rotor blade segment (second connection end of the second rotor blade segment shown to be close to the first connection end in fig. 5 of Sanz);
partially screwing the connecting bolts into the second connection end (see bolt 8 sticking out of the second connection end in fig. 5 of Sanz); providing an axially directed force between the first pieces and second pieces of each pretensioning unit (turning locking sleeve 34 or the hydraulic cylinder 32 in fig. 3 of Bucknell, as used to modify Sanz, would lead to one of those components moving away from housing 31);
axially pushing the first pieces and the second pieces of each pretensioning unit apart from each other along the corresponding connecting bolts against the respective connection ends, such that the corresponding connecting bolts are preloaded (outward movement of annular piston 32, or alternatively outward movement of locking sleeve 34, relative to housing 31 would lead to a preload of 38 in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 31, the combination of Sanz and Bucknell comprises the method of claim 30, wherein the first piece and the second piece of each pretensioning unit are coupled to each other via a thread (see housing 31 and locking sleeve 34 which are coupled via a thread in fig. 3 of Bucknell, as used to modify Sanz), and wherein, in the step of axially pushing, the first piece and the second piece of each pretensioning unit are screwed apart from each other for preloading the corresponding bolt (screwing apart locking sleeve 34 and housing 31 would create an axial force on 38 therefore preloading it in fig. 3 of Bucknell, as used to modify Sanz).
Regarding Claim 32, the combination of Sanz and Bucknell comprises the method of claim 30, wherein each pretensioning unit is formed as a hydraulic nut unit (see pretensioner 30 in fig. 3 of Bucknell, as used to modify Sanz), and wherein, in the step of axially pushing, the first piece and the second piece of each pretensioning unit are hydraulically pushed apart from each other (hydraulic pressure into internal passage 35 would fill cavity 36 and push annular piston 32 away from housing 31 in fig. 3 of Bucknell, as used to modify Sanz) for preloading the corresponding bolt (38 fig. 3 of Bucknell, as used to modify Sanz).
Allowable Subject Matter
Claims 19-20, 22, 24-25 and 33 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
Regarding Claims 19-20 and 24-25, it was determined to be non-obvious to modify the combination of Sanz and Bucknell such that ‘the first piece or second piece or a screwing piece is in contact to said connecting bolt in a form fit manner so as to permit a screwing force to be applied to said connecting bolt’ given that the shaft in Bucknell, as used to modify Sanz, is rounded. It would be non-obvious to further modify the components of Bucknell used to modify Sanz given this.
Regarding Claim 22 and 33, the limitation “wherein said lock nut is screwed against said first piece to hold said first piece and second piece in position relative to each other”, in context with the other limitations of the claim, rendered it non-obvious over the prior art of record. The combination of Sanz and Bucknell would not have been modifiable to meet this limitation given how separated and independent the annular piston is from the locking sleeve as shown in fig. 3 of Bucknell.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 10584677 – US patent grant of prior art cited above.
US 8510947, US 10767624, US 9797369, US 11220994, US 10883472 and US 11994101 – disclose various segmented wind turbine blades with bolted together segments.
US 4854798, US 10801625 and DE4405974C1 – discloses various apparatus for tensioning bolt via hydraulics or threading interfaces.
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/W.L.F./Examiner, Art Unit 3745
/COURTNEY D HEINLE/Supervisory Patent Examiner, Art Unit 3745
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