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 .
Claims 1-20 are currently pending. Claims 13-16 are withdrawn from consideration. Claims 1-12 and 17-20 are rejected.
Response to Arguments
Applicant’s arguments, see Pg. 9 of the remarks, filed November 12, 2025, with respect to the rejections of Claims 4 and 12 under 35 U.S.C. 112(b) have been fully considered and are persuasive in light of amendments. The rejections of Claims 4 and 12 under 35 U.S.C. 112(b) have been withdrawn.
Please note that while Applicant’s remarks state Claim 7 has been amended, it has not been amended.
Applicant’s arguments, see Pg. 9 of the remarks, with to the rejections in view of Stiehler (US 9,845,685 B2) have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
A new grounds of rejection is made regarding the claims addressed by Cellier (see next section). Since the new grounds of rejection also applies to the claims addressed by Stiehler, the rejections of Stiehler under 35 U.S.C. 102 are not repeated to reduce redundant rejections. It is noted though that the claim does not clarify the aspect of “linear”. Linear does not have to be the same manner illustrated by the application and can be interpreted as radially linear, like in a honeycomb.
Applicant’s arguments, see Pg. 9-10 of the remarks, filed with respect to the rejections in view of Cellier (FR 3026428 A1)* have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Shepherd et al. (US 2012/0230818 A1).
*Please note the citation of Cellier on Pg. 5 of the Non-Final of August 15, 2025 uses the incorrect reference number. However, the correct number is present elsewhere and Applicant has responded appropriately with the correct document so this typographical error did not affect prosecution.
Applicant notes the structure (50) taught by Cellier are wipers, not an abradable coating. The Office finds this argument to be persuasive. Therefore, the rejection has been withdrawn. However, the claims are believed to be still anticipated by Shepherd as detailed in the rejection below. Since there were claims rejected only by Cellier, this action will be considered Non-Final as said claims have not been properly rejected.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on February 23, 2026 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Objections
Claim 20 is objected to because of the following informalities:
Regarding Claim 20, Line 2 recites “wherein and each”. The “and” appears to be grammatically incorrect.
Appropriate correction is required.
Claim Rejections - 35 USC § 112(b)
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.
Claim 7 is 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 Claim 7, the term “substantially” is a relative term which renders the claim indefinite. The term “substantially” 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. Accordingly, it is unclear what range of angles of the notches and the median line are being claimed.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1, 4-5, 7-12, 17-20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Shepherd et al. (US 2012/0230818 A1), hereinafter Shepherd.
Regarding Claim 1, Figures 2, 3, and 4B of Shepherd disclose a blade (27) for a continuous flow machine, wherein the blade (27) is formed along a radial direction (vertical in Figure 2), comprising: a blade tip (29) and a blade cross-sectional profile with a pressure side (42) and a suction side (43), wherein the blade (27) comprises a blade tip surface (surface of 29) which is opposite a housing inner wall (21) during operation, wherein the blade tip surface comprises an abradable coating (not illustrated), wherein the abradable coating is formed in such a way that the abradable coating is worn during operation when coming into contact with the housing inner wall (21), wherein the abradable coating comprises an abradable coating surface (70 or covering 70), wherein linear notches (see 70 and 71, in region D1 outward of D2, forming notches) are arranged on the abradable coating surface [0070]. Note that while the abradable coating is not illustrated, Shepherd contemplates the blade tip to be a deformable tip. An abradable coating is used in place of or in combination with the surface (70) of the deformable tip [0029, 0077]. Thus, the abradable coating adopts the shaping illustrated in Figure 4B. The aspect of being worn is intended use of the claimed structure, but it is noted abradable coatings are intended to be abraded, i.e. worn.
Regarding Claim 4, Shepherd discloses the blade as set forth in Claim 1.
Figure 3 of Shepherd discloses wherein the blade cross-sectional profile comprises a median line (C), wherein the abradable coating is arranged along the median line. Paragraphs [0029, 0077] contemplate the abradable coating being the tip or combined with the tip (29), which is illustrated along the median line (C).
Regarding Claim 5, Shepherd discloses the blade as set forth in Claim 1.
Figure 3 of Shepherd discloses wherein the blade (27) has a leading edge (44) and a trailing edge (45), wherein the abradable coating is arranged from the leading edge (44) as far as the trailing edge (45). The coating applies to the tip region (29) and surface (70), which extends between leading and trailing edges (44, 45) [0029, 0077].
Regarding Claim 7, Shepherd discloses the blade as set forth in Claim 4.
Figures 3 and 4B of Shepherd disclose wherein the notches (formed by 70, 71) are formed substantially perpendicular to the median line (C). This is either radially or circumferentially [0070].
Regarding Claim 8, Shepherd discloses the blade as set forth in Claim 1.
Figure 4B of Shepherd discloses wherein distances of the notches (formed by 70, 71) from one another are equidistant. This is illustrated by the notches.
Regarding Claim 9, Shepherd discloses the blade as set forth in Claim 1.
Figures 3 and 4B of Shepherd disclose wherein the abradable coating is formed continuously from the pressure side (42) as far as the suction side (43). The coating is across the tip (29), which is between the two sides (42, 43) [0029, 0077].
Regarding Claim 10, Shepherd discloses the blade as set forth in Claim 1.
Shepherd discloses wherein the abradable coating is formed in such a way that abrasion occurring during operation by a housing inner wall leads to the abradable coating being worn away, wherein as a result, a contact surface produced by abrasion is produced, wherein the contact surface becomes wider in the radial direction toward a blade root (end closest to 25 in Figure 3) as a result of further abrasion. This claim is describing what happens during the removal of material as the material is abraded away. Paragraph [0077] notes the abradable coating is abraded, i.e. removed. Additionally, the result of the abrasion as claimed is considered intended use of the claimed structure. For instance, rubbing away material at different angles result in different geometries.
Regarding Claim 11, Shepherd discloses the blade as set forth in Claim 1.
Figures 3 and 4B of Shepherd disclose wherein the abradable coating is formed on the blade tip surface (surface of 29) in such a way that the abradable coating, viewed in cross section, represents a tip at an obtuse angle. The coating is used in place of or covers the illustrated tip surface [0029, 0077]. The claim does not specify what cross section or angle. The tip surface is merely a line when a cross section is taken. Any cross section may be taken in which the tip appears obtuse in a particular view.
Regarding Claim 12, Shepherd discloses the blade as set forth in Claim 1.
Shepherd discloses wherein the abradable coating has a slot, which is arranged in such a way that wear of the abradable coating leads to a measurable length L of the slot, and a height of the abradable coating is determinable via the length L. The coating is used in place of or covers the illustrated tip surface (surface of 29) [0029, 0077]. Figure 4B of Shepherd illustrates notches (formed by 70, 71), which any one is selectable to satisfy the broadest reasonable interpretation of the claimed slot. Since abrading removes material of portions forming the slot, a measurable L, such as in the radial direction, is capable of determining a height. For instance, of L is a radial dimension of the slot, the height is determinable by measuring a difference in the same direction.
Regarding Claim 17, Shepherd discloses the blade as set forth in Claim 4.
Figures 3 and 4B of Shepherd disclose wherein the median line (C) is curved, and wherein notches (formed by 70, 71) at different locations along the median line (C) are oriented transverse to one another. Paragraph [0070] notes the notches to be formed by ribs that are perpendicular to at least one area of the suction and/or pressure surface (43, 42). Combined with the curved nature of the median line (C) in Figure 3, this means that the orientations of the notches are not parallel. Paragraph [0070] even contemplates not being parallel.
Regarding Claim 18, Shepherd discloses the blade as set forth in Claim 12.
Figures 3 and 4B of Shepherd disclose wherein the blade (27) defines a median line (C), and wherein the slot is recessed from the abradable coating surface and is oriented transverse to the median line (C). As noted above in Claim 12, any notch (formed by 70, 71) is interpretable as the claimed slot. Said notch is recessed from the abradable coating surface (outer most surface). It is transverse because it crosses the median line (C) as it extends between pressure and suction sides (42, 43).
Regarding Claim 19, Shepherd discloses the blade as set forth in Claim 1.
Figure 4B of Shepherd discloses an abrasion indicator comprising a recess (any of the notches formed by 70, 71) that is recessed from a contact surface (radially outer surface) of the abradable coating; wherein the recess comprises a bottom surface (U forming the notch) that is disposed at an angle (forms approximately 90° angle with outermost surface) relative to the contact surface; wherein during progressive abrasion of the contact surface the contact surface intersects the bottom surface and a location where the contact surface intersects the bottom surface changes; and wherein an amount of wear of the abradable coating surface is associated with the location. The coating is used in place of or covers the illustrated tip surface [0029, 0077]. Note that limitations from the figures of the application are not to be improperly imported into the claims. The structure of the illustrated notch (formed by 70, 71) satisfies the current claim. As wear occurs, the intersection will cut more and more radially inwards. See also the annotated Figure 4B’ below.
PNG
media_image1.png
616
966
media_image1.png
Greyscale
Regarding Claim 20, Shepherd discloses the blade as set forth in Claim 1.
Figures 3 and 4B of Shepherd disclose wherein and each notch (formed by 70, 71) defines a respective plane that is oriented transverse to a median line (C) of the blade (27). The notches have a radial extent that crosses line (C).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
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.
Claims 2-3 are rejected under 35 U.S.C. 103 as being unpatentable over Stiehler et al. (US 9,845,685 B2), hereinafter Stiehler.
Regarding Claims 2-3, Shepherd teaches the blade as set forth in Claim 1.
Shepherd does not expressly teach wherein the abradable coating is provided with a lubricant (Claim 2), wherein the lubricant comprises graphite and/or hexagonal boron nitride (Claim 3) as claimed. However, such a material would have been obvious in view of Stiehler.
Stiehler teaches known materials suitable for use in abradable coatings includes graphite and/or hexagonal boron nitride. Such materials provide inert fillers that can be integrated, forming a simple run in that protects materials (Col. 5, Lines 6-23). The selection of a known material based on its suitability for its intended use supports a prima facie case of obviousness (see MPEP 2144.07). The labeling of it as a “lubricant” does not change the claimed material compared to the teachings of Stiehler.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the blade taught by Shepherd such that the abradable coating is provided with a lubricant (Claim 2), wherein the lubricant comprises graphite and/or hexagonal boron nitride (Claim 3) as evidenced by Stiehler, since the selection of a known material based on its suitability is considered obvious. Additionally, the material provides the benefit of forming simple run in that is known to provide a degree of protection.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Shepherd in view of Walker et al. (US 2019/0309759 A1), hereinafter Walker.
Regarding Claim 6, Shepherd teaches the blade as set forth in Claim 4.
Figure 3 of Shepherd teaches wherein a length of the median line (C) is D (see line being present with a length).
Shepherd does not expressly teach the abradable coating is arranged only in a region upstream of a trailing edge, wherein: d = (0.4 to 0.9) x D, where d is the length of the abradable coating along the median line as far as the trailing edge as claimed. However, such a region would have been obvious in view of Walker.
Figure 2 of Walker teaches a blade with an abradable portion (35) [0096]. Note that the addition of abradable material decreases the clearance compared to a clean blade. The abradable portion (35) is arranged only in a region upstream of a trailing edge (TE), along a length d (b in Walker) (note the median and chord progress in the same direction, leading to trailing). This is because the clearance changes due to thermal expansion during operation, with a gradually reducing inner diameter further downstream. A small clearance is desirable while leaving a larger clearance and the trailing edge portion reduces the possibility of contact [0093]. The positioning of the smaller clearance with the abradable portion (35) is desirable at the position of the maximum momentum generated by leakage gas [0084]. Therefore, Walker provides evidence that the particular size of d is a results-effective variable, to which one of ordinary skill would routinely optimize (see MPEP 2144.05, II).
It would have been obvious to one of ordinary skill before the effective filing date of the claimed invention to modify the blade taught by Shepherd such that the abradable coating is arranged only in a region upstream of a trailing edge, wherein: d = (0.4 to 0.9) x D, where d is the length of the abradable coating along the median line as far as the trailing edge as exemplified by Walker, since one of ordinary skill would provide a larger clearance proximate the trailing edge to mitigate contact while routinely optimizing the length so that the positions where maximum momentum generated by leakage gas is covered.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Shepherd. Claim 8 is rejected again for purposes of expediting prosecution assuming the figures are not sufficiently illustrating the claim.
Regarding Claim 8, Shepherd teaches the blade as set forth in Claim 1.
Shepherd does not expressly teach wherein distances of the notches from one another are equidistant as claimed.
However, the courts have held various practices to be routine expedients. One such practice is a change in relative dimensions. Where the only difference between the prior art is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct (see MPEP 2144.04, IV, A). In Figure 4B of Shepherd, the distances between notches (formed by 70, 71) is the relative dimension with respect to the extent of the surface (70). The distance as illustrated is at least close to equidistant. There is currently no evidence of record of the difference in performance of a blade with the distance illustrated by Shepherd compared to the claimed equidistant. Therefore, such a difference in relative dimensions is considered a matter of design choice.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the blade taught by Shepherd such that distances of the notches from one another are equidistant, since such a feature resulting from a difference in relative dimensions is considered an obvious matter of design choice.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to COURTNEY D HEINLE whose telephone number is (571)270-3508. The examiner can normally be reached Monday-Friday (9:00am-5:00pm).
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, Alford Kindred can be reached at (571) 272-4037. 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.
/COURTNEY D HEINLE/Supervisory Patent Examiner, Art Unit 3745