Ex Parte Romanov et al

Patent Trial and Appeal Board

Nov 23, 2018

13597745 (P.T.A.B. Nov. 23, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
13/597,745 08/29/2012 Dmitriy A. Romanov
54549 7590 11/27/2018
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
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
ATTORNEY DOCKET NO.
62335US01;
67097-1990PUS1
CONFIRMATION NO.
1040
EXAMINER
WHITE, ALEXANDER A
ART UNIT PAPER NUMBER
3745
NOTIFICATION DATE DELIVERY MODE
11/27/2018 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
ptodocket@cgolaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte DMITRIY A. ROMANOV,
BRIAN R. PELLETIER, and RUSSELL E. KEENE 1
Appeal2018-002733
Application 13/597,745
Technology Center 3700
Before JAMES P. CALVE, RICHARD H. MARSCHALL, and
ARTHUR M. PESLAK, Administrative Patent Judges.
CAL VE, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Office Action
finally rejecting claims 1--4, 7, 8, and 10-31. We have jurisdiction under
35 U.S.C. § 6(b).
We AFFIRM.
1 United Technologies Corporation is identified as the real party in interest.
Appeal Br. 1.
Appeal2018-002733
Application 13/597 ,745
CLAIMED SUBJECT MATTER
Claims 1, 14, and 24 are independent. Claim 1 is reproduced below.
1. A blade outer air seal assembly for a gas turbine engine,
compnsmg:
a main body portion extending along an axis, the main
body portion having a radially inward facing surface and at least
one radially outward facing surface, wherein the main body
portion comprises a single crystal nickel alloy having a sulfur
content that is equal to or below 1 part per million;
a passage provided in the main body portion between the
at least one radially inward facing surface and the at least one
radially outward facing surface, the passage having a first portion
and a second portion transverse to the first portion, and wherein
airflow inlets to the passage are in the at least one radially
outward facing surface and airflow outlets from the passage are
in a circumferentially facing surface, and the radially inward
facing surface is free from inlets or outlets to the passage;
a first attachment portion disposed at a leading edge of the
main body portion and a second attachment portion disposed at
a trailing edge of the main body portion, each of the at least one
attachment portions having a flange extending axially aft; and
at least one rib disposed along the axis radially outward of
the second portion, the at least one rib circumferentially aligned
with at least one of the first and second attachment portions.
REJECTIONS
Claims 1--4, 7, 12, 13, 23, and 24 are rejected under 35 U.S.C.
§ I03(a) as unpatentable over Durocher (US 7,520,715 B2, iss. Apr. 21,
2009), Hu (US 2009/0185944 Al, pub. July 23, 2009), Fujikawa (US
6,602,048 B2, iss. Aug. 5, 2003), and Nichols (US 7,387,488 B2, iss. June
17, 2008).
2
Appeal2018-002733
Application 13/597 ,745
Claim 8 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Durocher, Hu, Fujikawa, Nichols, and Koyabu (US 2011/0182724 Al, pub.
July 28, 2011 ).
Claims 10 and 11 are rejected under 35 U.S.C. § I03(a) as
unpatentable over Durocher, Hu, Fujikawa, Nichols, and Belanger (US
2012/0027574 Al, pub. Feb. 2, 2012).
Claims 14, 15, 18, 19, 28, and 31 are rejected under 35 U.S.C.
§ I03(a) as unpatentable over Durocher, Belanger, and Nichols.
Claims 16 and 17 are rejected under 35 U.S.C. § I03(a) as
unpatentable over Durocher, Belanger, Nichols, and Koyabu.
Claim 20 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Durocher, Belanger, Nichols, and Fujikawa.
Claims 21, 22, and 30 are rejected under 35 U.S.C. § I03(a) as
unpatentable over Fujikawa, Belanger, and Nichols.
Claims 25 and 26 are rejected under 35 U.S.C. § I03(a) as
unpatentable over Durocher, Hu, Fujikawa, and Nichols as evidenced by
Liotta (US 5,993,150, iss. Nov. 30, 1999), Fujikawa, and Joe (US 2010/
0232929 Al, pub. Sept. 16, 2010).
Claim 27 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Durocher, Belanger, Nichols, and Hu.
Claim 29 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Fujikawa, Belanger, Nichols, and Hu.
3
Appeal2018-002733
Application 13/597 ,745
ANALYSIS
Claims 1-4, 7, 12, 13, 23, and 24
Unpatentable Over Durocher, Hu, Fujikawa, and Nichols
Appellants argue claims 1--4, 7, 12, 13, 23, and 24 as a group. Appeal
Br. 5---6. We select claim 1 as representative, with claims 2--4, 7, 12, 13, 23,
and 24 standing or falling with claim 1. 37 C.F.R. § 4I.37(c)(l)(iv).
Regarding claim 1, the Examiner relies on Durocher to teach a blade
outer air seal with a main body portion (shroud segment 42) passage with a
first portion (inlet cavity 68) and a second portion (transpiration holes 66)
transverse to first portion 68 with airflow inlets 68 in a radially outwardly
facing surface and airflow outlets 70 in an axially facing surface. Final Act.
3. The Examiner relies on Hu to teach an improved single crystal metal
alloy as claimed. Id. at 4. The Examiner relies on Fujikawa to teach an air
passage with a first portion (inlet opening 63) and transverse second portion
(cooling passage 64) and a rib (axial rib 10a) as claimed. Id. The Examiner
relies on Nichols to teach a blade outer air seal and a passage with airflow
inlets 66, 72, 78 in a radially outward facing surface and airflow outlets 70,
74, 76 in a circumferentially facing surface as claimed. Id. at 5.
Appellants argue that replacing the existing outlets of Durocher with
those of Nichols would result in no cooling film being provided to turbine
vane shroud 38. Appeal Br. 5. Appellants also argue that adding outlets to
Durocher to direct cooling air in the circumferential facing direction would
destroy the goals of Durocher of cooling turbine vane shroud 38. Id. at 5---6.
These arguments are not persuasive because the Examiner does not
propose to replace Durocher's trailing edge outlets 70 with circumferential
facing outlets of Nichols. Final Act. 5---6; Ans. 4.
4
Appeal2018-002733
Application 13/597 ,745
Instead, the Examiner "modifies Durocher by adding circumferential
outlets to the existing structure ... [ so that] the structure would still allow
for the ejection of cooling air through the axial holes." Ans. 4. We agree
with the Examiner that this modification would not destroy the ability of the
axial air outlets 70 of Durocher to cool turbine vane outer shroud 38. The
Examiner thus improves Durocher's cooling capacity by adding the ability
to cool the circumferential surfaces of Durocher's turbine shroud 32 and the
adjacent shroud sidewalls. Final Act. 6 ("provide impingement cooling to
adjacent blade outer air seal segments"); see also Nichols, 4: 1--4 ("[A ]ir
exiting through the sidewall cooling holes 70, 7 6 provides impingement
cooling on the adjacent shroud sidewalls."). The Examiner's reason for
adding circumferential air outlets of Nichols to Durocher is supported by
express teachings of Nichols as to the benefits of providing such outlets.
This teaching also is consistent with Durocher's configuration to provide
transpiration holes 66 in platform 44 of turbine shroud 32 for effective
cooling of platform 44. See Durocher, 3:55---62, Fig. 2. Adding passages for
circumferential outlets, as Nichols teaches, would add more passages to cool
Durocher's platform 44, as Durocher teaches is desirable to do. Id.
A skilled artisan, as a person of ordinary creativity, would be able to
combine the teachings of Nichols and Durocher without undermining the
ability of Durocher to continue to cool turbine vane shroud 3 8 with axial air
outlets 70. Indeed, Nichols teaches a configuration that provides cooling to
both axially-facing edges and circumferentially facing edges by placing air
outlets on both surfaces. Nichols also configures airflow inlets 66, 72, 78 to
provide sufficient cooling airflow to outlets 70, 74, 76 on both surfaces.
Nichols, 3:25--4:22 (to reduce and control bond coat temperature), Figs. 2-5.
5
Appeal2018-002733
Application 13/597 ,745
For all of the foregoing reasons, we are not persuaded by Appellants'
attorney arguments that adding circumferential facing outlets of Nichols to
Durocher would reduce the cooling film to Durocher's turbine vane shroud
38 "by virtue of redirection of air in a circumferential direction." Reply Br.
1. Nichols teaches to add airflow inlets to supply sufficient air to airflow
outlets on both the axial surfaces and the circumferential facing surfaces.
Thus, we sustain the rejection of claims 1--4, 7, 12, 13, 23, and 24.
Claim 8
Unpatentable Over Durocher, Hu, Fujikawa, Nichols, and Koyabu
Appellants argue the patentability of claim 8 based on its dependency
from claim 1. Appeal Br. 6. Because we sustain the rejection of claim 1,
this argument is not persuasive, and we also sustain the rejection of claim 8.
Claims 10 and 11
Unpatentable Over Durocher, Hu, Fujikawa, Nichols, and Belanger
To provide thermal protection to the shroud, Appellants add a thermal
barrier coating to the radially inward facing surface. Claim 10 depends from
claim 1 and recites that the thermal coating thickness "is substantially equal
to a thickness of an inner wall of the main body portion defined between a
floor of the passage and the radially inward facing surface." Appeal Br. 11
(Claims App.). We interpret this limitation to require the thickness of the
thermal coating to be about the same as the thickness of the inner wall that is
below the circumferential facing outlets. This meaning is consistent with an
ordinary meaning of "substantial" which is "being largely but not wholly
that which is specified." Definition of substantial by Merriam-Webster at
http://www.merriam-webster.com/dictionary/substantial (last viewed Nov.
15, 2018).
6
Appeal2018-002733
Application 13/597 ,745
This meaning is consistent with the Specification, which discloses that
the thickness 116 of thermal barrier coating 110 is substantially equal to a
thickness 118 of an inner wall 120 of the main body portion 54 between a
floor 122 of the cooling passages 86 and the radially inward facing surface
64. Spec. ,r 49. Appellants' Figure 3 illustrates the thickness 116 of thermal
barrier coating 110 as about the same as thickness 118 of inner wall 120.
We agree with the Examiner that Belanger teaches a thermal barrier
coating 78 having about the same thickness as the inner wall of the main
body as recited in claim 10. Final Act. 9; Ans. 5. Belanger teaches that the
depth of the recess "d" in which thermal barrier coating 78 fits into main
body 50 "may extend about half of the distance between the [inner diameter]
face of the [blade outer air seal] segment and the radially inward most extent
of any of the cooing air passages 70, such as illustrated in FIG. 4." Belanger
,r 34 ( emphasis added), Fig. 4; Ans. 5 ( citing id.). Thus, Belanger teaches
that the thickness of coating 78 is substantially equal to the thickness of that
portion of body 50 between coating 78 and air passages 70 as claimed.
Appellants argue that the thickness of the inner body wall of Belanger
between thermal barrier coating 78 and air passages 70 "varies at multiple
points in each cooling air passage 70" in Figure 4, and the drawings are not
disclosed as drawn to scale. Appeal Br. 6-7; Reply Br. 2. This argument is
not persuasive because Belanger discloses the thickness of thermal barrier
coating 78 to be substantially equal to the thickness of body 50 below air
passages 70 as claimed. The slight variations noted by Appellants mean the
thickness may not be identically equal at all points along the coating, but
claim 10 only requires "a thickness" of the thermal barrier coating to be
"substantially equal" to "a thickness" of the wall, which Belanger discloses.
7
Appeal2018-002733
Application 13/597 ,745
Thus, we sustain the rejection of claim 10 and its dependent claim 11
for which no separate arguments are presented. See Appeal Br. 6-7.
Claims 14, 15, 18, 19, 28, and 31
Unpatentable Over Durocher, Belanger, and Nichols
Independent claim 14 recites a gas turbine engine assembly with blade
outer air seal assemblies configured with airflow outlets in a circumferential
facing surface as recited in claim 1 and a thermal barrier coating having the
thickness recited in claim 10. Appeal Br. 12 (Claims App.). The Examiner
again relies on Nichols and Belanger to teach these features in combination
with Durocher's teachings as for claims 1 and 10 above. Final Act. 10-12.
Appellants argue that claim 14 is patentable for the same reasons as asserted
for claims 1 and 10. Appeal Br. 7. These arguments are not persuasive for
the reasons discussed above for the rejections of claims 1 and 10. Thus, we
sustain the rejection of claim 14 and also of claims 15, 18, 19, 28, and 31 for
which no separate arguments are presented. See 37 C.F.R. § 4I.37(c)(l)(iv).
Claims 16, 17, and 20
Unpatentable Over Durocher, Belanger, Nichols, and Koyabu/Fujikawa
Appellants argue the patentability of claims 16, 17, and 20 based on
their dependency from claim 14. Appeal Br. 7. Because we sustain the
rejection of claim 14, this argument is not persuasive, and we also sustain
the rejection of claims 16, 17, and 20.
Claims 21, 22, and 30
Unpatentable over Fujikawa, Belanger, and Nichols
Independent claim 21 recites a method of forming a blade outer air
seal with a thermal barrier coating with the thickness recited in claim 1. The
Examiner again relies on Belanger for this feature. Final Act. 18.
8
Appeal2018-002733
Application 13/597 ,745
Appellants argue that this rejection is improper because Belanger does
not teach this feature for the reasons asserted for claims 10 and 14. Appeal
Br. 7. These arguments are not persuasive for the reasons discussed above
for claim 10. Thus, we sustain the rejection of claim 21 and its dependent
claim 22, for which no separate arguments are presented. See id. at 6-7.
Claim 30 depends from claim 21 and recites that the first portion of
the air passage "is linear from an inlet on the radially outward facing surface
to the second portion." Appeal Br. 14 (Claims App.). The Examiner relies
on Fujikawa to teach this feature, in part, and reasons that it would have
been an obvious design choice to make the first portion of Fujikawa linear as
claimed "for the purpose of allowing cooling air flow to move from the inlet
to the second portion of the passage." Final Act. 20-21; Ans. 7 (same). The
Examiner also finds that Figure IA of Fujikawa teaches "a largely linear
path" leading up to a curved portion. Ans. 6. We agree.
Claim 30 requires the first portion to be linear from an inlet "to the
second portion" and claim 21 recites "a second portion extending generally
circumferentially transverse to the first portion." Because the curved part of
Fujikawa's cooling passage 64 is generally circumferentially transverse to
opening 63 in Figure 1 A, this curved part is part of the second portion. The
first portion of the passage that extends from opening 63 to the curved part is
linear as recited in claim 30. Even if Fujikawa itself did not disclose this
limitation, the Examiner also cites Figure 1 of Koyabu, Figure 2 of Liotta,
and Figure 3 of Joe as evidence that linear cooling passages are known in the
art and would have been obvious to use in Fujikawa for cooling. Id. at 7.
We agree that this evidence supports the Examiner's finding that linear
cooling passages are known in the art and would have been obvious to use.
9
Appeal2018-002733
Application 13/597 ,745
The teachings of Fujikawa thus render obvious a linear first portion
under our interpretation of "first portion" and "second portion" or in light of
the teachings of Koyabu, Liotta, and Joe that a linear first portion would
have been an obvious modification of Fujikawa's cooling passage to connect
a cooling plenum to a blade outer air seal to provide cooling thereto.
In view of the Examiner's findings and reasoning set forth above that
a linear passage "would simply allow for cooling air to pass from an inlet to
an outlet" (Ans. 7), the Examiner set forth reasons supported by a rational
underpinning to include a linear first portion in Fujikawa. Appellants do not
address adequately the Examiner's reasons. Appeal Br. 8; Reply Br. 2; see
Final Act. 21 ("for the purpose of allowing cooling air flow to move from
the inlet to the second portion of the passage"); Ans. 7 (Fujikawa uses
predominantly linear path, and Koyabu, Liotta, and Joe all teach the use of
linear cooling passages to connect cooling plenums to blade outer air seals).
The Examiner's findings and determination set forth above establish a
prima facie obviousness case, which Appellants may rebut with evidence of
the criticality of the claimed linear first portion. Appellants have not done
so. See Appeal Br. 8. Indeed, Appellants disclose as support for this feature
only Figure 3 of their disclosure. Id. at 5. Absent a disclosure of a unique
function or purpose served by the linear first portion, the Examiner is not
precluded per se from reliance on design choice as an alternative basis for
rejecting claim 30 as long as the Examiner provides an adequate reason for
making the asserted design choice. The Examiner has provided reasons in
the Final Office Action and Answer as discussed above. Appellants do not
apprise us of error in those reasons. See Reply Br. 2; Appeal Br. 8. Thus,
we sustain the rejection of claim 30.
10
Appeal2018-002733
Application 13/597 ,745
Rejections of Dependent Claims 25-27 and 29
Appellants argue the patentability of dependent claims 25-27 and 29
based on their dependency from a respective one of independent claims 1,
14, or 21. Appeal Br. 8-9. Because we sustain the rejections of claims 1,
14, and 21, these arguments are not persuasive, and we also sustain the
rejections of claims 25-27 and 29.
DECISION
We affirm the rejections of claims 1--4, 7, 8, and 10-31.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l )(iv).
AFFIRMED
11