United Technologies Corporation

Patent Trials and Appeals Board

Mar 31, 2021

2020002852 (P.T.A.B. Mar. 31, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/708,711 09/19/2017 Christopher W. Strock 97386US01-U(17-239) 1151
52237 7590 03/31/2021
Bachman & LaPointe, P.C.
900 Chapel St., Suite 1201
New Haven, CT 06510
EXAMINER
TAYLOR JR, ANTHONY D
ART UNIT PAPER NUMBER
3747
MAIL DATE DELIVERY MODE
03/31/2021 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte CHRISTOPHER W. STROCK
Appeal 2020-002852
Application 15/708,711
Technology Center 3700
Before EDWARD A. BROWN, BRETT C. MARTIN, and
JEREMY M. PLENZLER, Administrative Patent Judges.
Opinion for the Board Filed by Administrative Patent Judge MARTIN.
Opinion Dissenting filed by Administrative Patent Judge PLENZLER.
MARTIN, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–5, 7–11, 13–18, and 20–26. See
Final Act. 1. We have jurisdiction under 35 U.S.C. § 6(b).

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real party in interest as United Technologies
Corporation. Appeal Br. 2.
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We AFFIRM IN PART.
CLAIMED SUBJECT MATTER
The claims are directed “to an abradable outer air seal for a turboshaft
engine.” Spec. ¶ 1. Claim 1, reproduced below, is illustrative of the claimed
subject matter:
1. A seal for a gas turbine engine, comprising: a substrate;
an abradable layer; and
an interlayer between the substrate and the abradable
layer, the interlayer thicker than the abradable layer and
containing abrasive particles of which at least some abrasive
particles protrude out of the interlayer and into the abradable
layer but do not extend beyond the abradable layer, wherein the
interlayer has an interlayer hardness that is higher than an
abradable layer hardness and higher than a substrate hardness.
REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Schell US 5,952,110 Sept. 14, 1999
Ghasripoor US 2014/0147242 A1 May 29, 2014

REJECTIONS
Claims 1–5, 7–11, 18, and 20 stand rejected under 35 U.S.C.
§ 112(b) as indefinite. Ans. 4.2
Claims 1–5, 7–11, 13–15, 18, and 20–26 stand rejected under
35 U.S.C. § 103 as unpatentable over Shipton and Schell. Final Act. 6.

2 The Examiner’s Answer indicates that the rejection of claims 8, 9, 13, 17,
and 23 under this same ground has been withdrawn in response to
Amendment filed on August 28, 2019. Ans.
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Claims 16 and 17 stand rejected under 35 U.S.C. § 103 as
unpatentable over Shipton, Schell, and Ghasripoor. Final Act. 18.
OPINION
Indefiniteness
Regarding claims 1 and 20, the Examiner asserts that “it is not clear as
to how the abrasive particles are not extending beyond the abradable layer,
since the abrasive particles are claimed such that they extend from the
abradable layer and into the interlayer, and as such, the abrasive particles are
in fact extending beyond the abradable layer.” Ans. 4 (emphasis added).
We agree with Appellant that “the claim is clear on its face in that the
abrasive particles do not extend from the abradable layer such that they
would not be in contact with the blade tip.” Reply Br. 2 (explaining that
Appellant’s “abradable layer initially protects the particles” because the
blade tip will first abrade the abradable layer before reaching the abrasive
particles in the next layer).
First, the Examiner acknowledges that the claims require that the
abrasive particles extend into the interlayer, which means that, as claimed,
the particles do, in fact, extend beyond the abradable layer in one direction.
The claim language, however, explains that the abrasive particles are
contained in the interlayer and “protrude [extend] . . . into the abradable
layer but do not extend beyond the abradable layer.” Thus, when read in
context, the claim language is clear that the abrasive particles extend from
the interlayer, into the abradable layer, but not beyond the abradable layer in
the direction opposite the interlayer. This configuration is depicted in Figure
1, for example. The Examiner appears to ignore the context of the claim
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itself when interpreting the claim language at issue. Accordingly, we do not
sustain the Examiner’s rejection of claims 1 and 20.
Regarding the rejection of claim 18, Appellant does not argue the
basis for the rejection, but has submitted an amendment to correct the issue
noted by the Examiner. Because this amendment has not officially been
entered, however, we summarily affirm the rejection of claim 18.
Accordingly, we sustain the rejection of claim 18 and do not sustain the
rejection of claims 1–5, 7–11, and 20 as being indefinite.
Obviousness
Regarding the rejection of claims 1–5, 7–11, 13–15, 18, and 20–26 as
unpatentable over Shipton and Schell, Appellant presents separate argument
for independent claims 1 (Appeal Br. 9–13) and 23 (id. at 17), but not for
independent claim 13.
The Examiner’s rejection of claim 1 relies on Shipton as teaching a
seal having some characteristics similar to Appellant’s claim, including an
interlayer (region 8) containing abrasive particles, but lacking abrasive
particles that extend into an abradable layer (outer region 10). Final Act. 6–
7. The Examiner then relies on Schell as teaching a “seal/coating” including
an abradable layer (ceramic layer 14), and an interlayer (alloy layer 12),
wherein abrasive particles 16 protrude out of the interlayer and into the
abradable layer. Final Act. 7 (citing Schell, Fig. 1). The Examiner
concludes that it would have been obvious to one of ordinary skill in the art
to modify Shipton’s seal to have at least some of the abrasive particles
protrude out of the interlayer and into the abradable layer, as suggested by
Schell, “to promote the service life of the abrasive particles and the
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seal/coating via having multiple layers of materially distinct composition(s)
each serving to anchor the abrasive particles.” Id.
Schell’s disclosed structure is a blade tip 18 of a turbine blade 10.
Where Schell discusses interaction of the blade tip with a ceramic shroud, it
explains that the configuration of the blade tip is meant to maintain the
appropriate interference gap by wearing the shroud by contact with the
abrasive particles. Schell col. 2, ll. 34–36. In other words, Schell has no
protection for the shroud at all and the blade tip/shroud arrangement merely
allows wearing away of the shroud from the start. Because Schell’s
arrangement is effectively the opposite of the claimed seal and the blade of
Shipton, a combination consistent with the teachings of Schell might include
abrasive particles extending through Shipton’s abradable layer, but also
extending exteriorly beyond that layer at the leading edge of the seal so as to
abrade the blade from the start. This, however, is not the goal of the claim
and goes against Shipton’s teachings, nor is this the Examiner’s proposed
combination.
Furthermore, we disagree with the Examiner’s finding that Schell’s
ceramic layer 14 is an “abradable layer,” as claimed. Schell discloses that
“[t]he ceramic layer 14 promotes the wear resistance of the coating 20 when
the blade tip 18 rubs the ceramic shroud.” See Schell, col. 5, ll. 7–9. As
such, ceramic layer 14 is designed to provide wear resistance (i.e., not wear),
as opposed to being an abradable layer that is designed to be more easily
abraded in service. Indeed, ceramic layer 14 and particles 16, which extend
exteriorly from ceramic layer 14 to be able to wear the shroud, protect the
underlying substrate and alloy layer 12 from contact with the shroud. See id.
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at col. 3, ll. 35–37. During this contact, the shroud is abraded, but ceramic
layer 14 is designed not to be abraded, in Schell.
In direct contrast, Appellant’s Specification discloses that the
abradable layer is softer than the interlayer (see Spec. ¶ 36), such that the
abradable layer has lower erosion resistance (see id. ¶ 37). As Schell’s
ceramic layer 14 is not an abradable layer, as this claim term would be
understood by one skilled in the art in view of Appellant’s Specification, the
Examiner’s finding that abrasive particles 16 protrude into the “abradable
layer” (i.e., ceramic layer 14) is also not supported by Schell. Accordingly,
the Examiner’s reliance on Schell is premised on unsupported factual
findings. We note, however, that where a conclusion of obviousness is not
supported by an adequate factual basis, the legal conclusion is in error. See
In re Warner, 379 F.2d 1011, 1017 (CCPA 1967).
With respect to claim 1, although Schell teaches abrasive particles in
the blade tip, Schell’s blade tip is designed so that the abrasive particles
extend beyond the purported abradable layer, in direct contradiction to the
claims. The abrasive particles extend outwardly from ceramic layer 14 to
wear the adjacent shroud. Both Shipton and Appellant’s claim contemplate
wear between the blade tip and the seal to occur first within the seal at an
abradable layer that contains no abrasive particles and then at the tip as the
wear reaches the abrasive particles. Schell, however, does not involve this
shifting of wear location because it is designed for the blade tip containing
the abrasive particles always to wear the shroud, not vice versa, and for
ceramic layer not to wear.
Again, incorporating Schell’s teachings into Shipton would appear to
result in abrasive particles wearing the blade tip from the beginning of
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service rather than shifting the wear from the seal to the tip as wear
progresses. This feature goes against the teaching of both Appellant’s claim
and Shipton. Given that Shipton’s abrasive particles do not extend into the
abradable layer, at all, the Examiner does not explain persuasively how one
of skill in the art would extend abrasive particles into Shipton’s abradable
layer without also extending them beyond that layer as taught in Schell.
It is not clear how one of ordinary skill in the art would apply Schell’s
teachings, which again are actually contrary to claim 1 and the teachings of
Shipton. Shipton not only does not desire abrasive particles at the leading
edge, but specifically discloses that the abrasive particles are confined to
region 8, and there are no abrasive particles in outer region 10 of the coating,
which provides free surface 12, that is, in the uppermost regions of the
abradable layer. See Shipton 4. In Shipton, if the engine is subjected to
severe g forces, or if damage occurs, more severe blade incursion may occur,
and the blade tips may begin to penetrate into the abrasive-containing
region. Id. Otherwise, blade tip incursion into coating 6 is confined to outer
region 10 without abrasive particles. Id. In contrast, Schell requires the
abrasive particles to be contained in and protrude exteriorly from the
ceramic layer to wear the shroud, without wearing the wear-resistant ceramic
layer.
As for the Examiner’s stated rationale for modifying Shipton in view
of Schell, Shipton contains the abrasive particles only in region 8 so that the
blade tip will normally only interact with the material of outer region 10.
The Examiner has not explained adequately why one of ordinary skill in the
art would, nevertheless, have extended the abrasive particles into outer
region 10 to promote anchoring of the particles. The Examiner does not
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identify any problem with the anchoring of the particles in region 8 in
Shipton. In that regard, it appears that the blade tip would not even be able
to reach the depth of the abrasive particles in region 8 unless and until outer
region 10 is first removed, such as by severe blade incursion. It is not
apparent how enhanced anchoring of the particles would even be relevant at
such time that the particles become exposed. In contrast, Schell teaches that
the abrasive particles are contained in both alloy layer 12 and ceramic layer
14 as the abrasive particles are subject to wear whenever they contact the
shroud during service, and both of these layers would be present during that
wear.
We do not agree that one of ordinary skill in the art would modify
Shipton in view of Schell in the proposed manner, which is contrary to the
teachings of Shipton to attempt to arrive at Appellant’s claimed invention.
The Examiner, thus, has not provided a reasonable basis with rational
underpinnings for the combination of Shipton with Schell. We therefore do
not sustain the Examiner’s rejection of claim 1.
Claim 13 does not contain the same prohibition against abrasive
particles extending beyond the abradable layer as recited in claim 1. Claim
13 recites “the interlayer . . . containing particles of which at least some
abrasive particles protrude out of the interlayer and into the abradable layer.”
Appeal Br. 22. Because we find that the Examiner’s rationale for modifying
Shipton lacks rational underpinnings, we likewise do not sustain the
rejection of claim 13 or its dependent claims. We do note, however, that
claim 20, which depends from claim 13, precludes the abrasive particles
from extending beyond the abradable layer in the same fashion as claim 1.
Accordingly, the above discussion regarding claim 1 also applies to claim
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20. Regarding the remaining claims dependent from claim 13, because they
depend from claim 13, the rejection of which we do not sustain, we likewise
do not sustain the rejection of these claims. Accordingly, we do not sustain
the Examiner’s rejection of claims 1–5, 7–11, and 13–22 as unpatentable
over Shipton and Schell.
As to claim 23, although it also does not contain the same prohibition
against abrasive particles extending beyond the abradable layer as recited in
claim 1, because we do not agree that the Examiner’s combination is based
upon a sound rationale, we likewise do not sustain the Examiner’s rejection
of claims 23–26.
As for claims 16 and 17, which depend ultimately from claim 13, the
Examiner’s reliance on Ghasripoor does not cure the deficiency in the
rejection of claim 13. Final Act. 18–19. Accordingly, we do not sustain the
rejection of claims 16 and 17 for the same reasons as for claim 13.
CONCLUSION
The Examiner’s rejections are AFFIRMED IN PART.
More specifically,
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DECISION SUMMARY
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1–5, 7–11,
13–15, 18,
20–26
103 Shipton, Schell 1–5, 7–11,
13–15, 18,
20–26
1–5, 7–11,
13–18, 20–
26
112 Indefiniteness 18 1–5, 7–11,
13–17, 20–
26
16, 17 103 Shipton, Schell,
Ghasripoor
16, 17
Overall
Outcome
18 1–5, 7–11,
13–17, 20–
26

TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED IN PART

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PLENZLER, Administrative Patent Judge, dissenting.
I agree with the decision to reverse the Examiner’s indefiniteness
rejection, but do not agree with the reasoning provided to reverse the
obviousness rejections.
The majority faults the Examiner for a number of reasons, none of
which are tied to any particular contention presented by Appellant. For
example, the majority faults the Examiner’s rationale regarding anchoring
abrasive particles. See, e.g., Final Act. 2–3 (discussing improved anchoring
of the abrasive particles); see also Ans. 21. That rationale, however, is not
disputed by Appellant. See, e.g., Appeal Br. 11–12 (alleging heat concerns
not addressed by the majority).
Because Appellant does not identify reversible error, I do not join the
majority with respect to the analysis of the obviousness rejections.