Ex Parte Praisner et al

Patent Trial and Appeal Board

Oct 18, 2017

12753211 (P.T.A.B. Oct. 18, 2017)

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.
12/753,211 04/02/2010 Thomas J. Praisner PA-11145U; 4113
67097-1305US1
54549 7590 10/20/2017
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
EXAMINER
HTAY, AYE SU MON
ART UNIT PAPER NUMBER
3745
NOTIFICATION DATE DELIVERY MODE
10/20/2017 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 THOMAS J. PRAISNER and ERIC A. GROVER
Appeal 2015-001034
Application 12/753,211
Technology Center 3700
Before JOHN C. KERINS, SUSAN L. C. MITCHELL, and
ARTHUR M. PESLAK, Administrative Patent Judges.
KERINS, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Thomas J. Praisner and Eric A. Glover (Appellants) seek our review
under 35 U.S.C. § 134 of the final rejection of claims 14—36. We have
jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.
Appeal 2015-001034
Application 12/753,211
THE INVENTION
Appellants’ claimed invention is directed to a gas turbine engine.
Claim 14, the only independent claim on appeal, is reproduced below, and is
illustrative:
14. A gas turbine engine comprising:
a compressor section;
a combustor section; and
a turbine section,
said turbine section including at least one stator
vane and at least one rotating blade,
said at least one stator vane including an inner
vane platform section, said inner vane platform section having a
leading edge, a trailing edge, and two circumferentially spaced
edges, and
said at least one rotating blade including a root section,
an airfoil section, and a rotor platform section between said
root section and said airfoil section, said rotor platform having
a leading edge, a trailing edge, and two circumferentially
spaced edges;
wherein said at least one stator vane and said at least one
rotating blade define a clearance gap in a radial direction
between an upper surface of one of said inner vane platform
section and said rotor platform section and an undersurface of
the other one of said inner vane platform section and said rotor
platform section;
wherein at least one of said rotor platform section and
said inner vane platform section has a non-axisymmetric
surface contour on a surface defining a portion of said clearance
gap, said surface contour being curved and non-axisymmetric
about an axis defined extending from the leading edge to the
trailing edge of said at least one of said rotor platform section
and said inner vane platform section, wherein said surface
contour is designed to counteract non-uniform static pressure
distortions engendered by combustion products flowing within
said clearance gap.
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Application 12/753,211
THE REJECTIONS
The Examiner has rejected:
(i) claims 14, 18—23, and 35 under 35 U.S.C. § 102(b) as being
anticipated by Naik (US 7,044,710 B2, issued May 16, 2006);
(ii) claims 14, 24—34, and 36 under 35 U.S.C. § 102(b) as being
anticipated by Kneeland (US 2011/0052387 Al, published Mar. 3, 2011);
and
(iii) claims 15—17 under 35 U.S.C. § 103(a) as being unpatentable
over Naik and Liang (US 2010/0074730 Al, published Mar. 25, 2010).
ANALYSIS
Claims 14, 18—23, and 35—Anticipation by Naik
The Examiner finds that Naik discloses each of the limitations of
claim 14, including a stator vane and a rotating blade define a clearance gap
in a radial direction between an upper surface of a rotor platform section and
an undersurface of an inner vane platform section. Final Act. 3—4. The
Examiner further finds that the rotor platform section has a non-
axisymmetric surface contour on a surface defining a portion of the
clearance gap, in the form of fins 8 arranged on the top side of the rotor
platform in the front region of the platform. Id. at 4. The Examiner further
finds that the surface contour provided by fins 8 is capable of counteracting
non-uniform static pressure distortions engendered by combustion products
flowing within the clearance gap. Id.
Appellants argue that Naik discloses a seal that is defined by seal fin 5
on a platform 4 of rotor blade 1, and a honeycomb 6 on platform 4 of turbine
vane 2. Appeal Br. 4—5, citing Naik, col. 3,11. 34—37. Appellants maintain
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Application 12/753,211
that fms 8 are disposed radially inwardly of seal fin 5, and that there is no
disclosure of fins 8 being configured to engage honeycomb 6 on turbine
vane 2. Id. According to Appellants, the result is that fms 8 do not define a
portion of the clearance gap in a radial direction, as claimed. Id. at 5.
Appellants additionally argue that the Examiner has not established that the
surface contour provided by fms 8 is designed to counteract non-uniform
static pressure distortions engendered by combustion products flowing
within the clearance gap. Id.
The Examiner counters that the clearance gap includes not only the
region between sealing fin 5 and honeycomb 6, but also the region in which
honeycomb 6 overlies fms 8, using an annotated version of Figure 2a of
Naik to show that the clearance gap has an axial component as well as a
radial component. Ans. 5—6. Under this interpretation, according to the
Examiner, the surface contour provided by fms 8 on the rotor blade
platform, in the region overlapped by honeycomb 6, defines a portion of the
clearance gap in a radial direction. Id. The Examiner additionally takes the
position that, “since Naik discloses the same physical features of the rotor
platform as claimed, it would inherently be capable of performing the . . .
function” of counteracting non-uniform static pressure distortions as
claimed. Id. at 7.
Notwithstanding that the breadth of claim 14 is such that, at first
blush, the Naik turbine section might appear to include all structural
limitations of the claim, we believe that Appellants have the better position
in terms of which portions of Naik correspond to the elements forming the
claimed clearance gap. We are not especially persuaded by Appellants’
argument that fms 8 do not define, with honeycomb 6, a portion of the radial
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Appeal 2015-001034
Application 12/753,211
clearance gap solely on the basis that the fins extend radially inwardly from
seal fin 5, and thus are spaced somewhat further away (at a larger gap) from
honeycomb 6. Claim 14 does not appear to limit the surface contour such
that the gap is defined only at the peripheral edge of one of the two
platforms, nor that the gap is to be a constant dimension axially or radially
over the entire region of overlap of the surfaces of the inner vane platform
and rotor blade platform.
Nonetheless, Naik discusses its structure in terms that reveal that Naik
regards the seal or clearance gap to be formed between seal fin 5 and
honeycomb 6 only. Naik describes that the cooling air leakage stream
passes through the seal formed by seal fin 5 and honeycomb 6, and only
after that point does the leakage stream interact with fins 8, with the fins
“ensuring] that the cooling air leakage stream 7 reaches the pressure side of
the turbine blade 1.” Naik, col. 3,11. 34^43, col. 1,11. 64—67, col. 2,11. 8—10.
That the seal or clearance gap in Naik is regarded as being provided
only by seal fin 5 and honeycomb 6 is evidenced in the Figure 2b
embodiment not relied on by the Examiner. That embodiment does not
include fins 8, yet provides a seal or clearance gap that controls the flow of
the cooling air leakage stream passing therethrough. Naik, Figure 2b, col. 3,
1. 55-col. 4,1. 3.
As such, the Examiner erred in regarding fins 8 in Naik as providing
the claimed non-axisymmetric surface contour on a surface defining a
portion of the radial clearance gap, as claimed. The rejection of claim 14 as
being anticipated by Naik is therefore not sustained. Similarly, the rejection
of claims 18—23 and 35, depending from claim 14, is not sustained.
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Application 12/753,211
Claims 14, 24—34, and 36—Anticipation by Kneeland
The Examiner finds that all limitations presented in claim 14 are
disclosed by Kneeland, including a curved surface contour being non-
axisymmetric about an axis defined extending from the leading edge to the
trailing edge of one of a rotor platform section and an inner vane platform
section. Final Act. 6—7. The Examiner identifies curved portions 60, 62, 70,
and 72 as meeting the claim limitation. Id. at 6.
Appellants point out that claim 14 requires that the non-axisymmetric
surface contour is to be on a surface defining a portion of the clearance gap,
which is itself recited as being defined in a radial direction between an upper
surface of one of the inner vane and rotor platform sections, and an
undersurface of the other of the platforms. Appeal Br. 7. Appellants
maintain that curved portions 60, 62, 70, and 72 in Kneeland are positioned
on leading edges 47, 57 or trailing edges 49, 59 of platforms 45, and extend
in axial directions away from blades 24, 40. Id. at 7—8 (citing Kneeland,
paras. 25—30, Figs. 4, 13). Appellants maintain that the curved portions
relied on by the Examiner are located on a different surface than a surface
defining a portion of the clearance gap in a radial direction. Id. at 8.
The Examiner replies that Figure 1 of Kneeland evidences that
clearance gaps shown therein extend in both radial and axial directions.
Ans. 12. After discussing various portions of the Kneeland disclosure, the
Examiner takes the position that, based on the Kneeland construction, “it is
inherent that the curved portions are located on the surfaces that define the
clearance gap in both radial and axial directions. Id. at 13.
Once again, Appellants have the better position. Appellants provide
an annotated version of Figure 13 from Kneeland, and again note that the
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Application 12/753,211
contouring of the curved portions is in an axial direction, not in a radial
direction, and it is improper to assume that the curved portions would
necessarily provide contour in a radial direction. Reply Br. 4—5. In Figure
13 of Kneeland, the radial direction would be along an axis extending in and
out of the plane of the page. The surfaces of the rotor platform shown
therein, one or more of which might define one boundary of a clearance gap
in a radial direction, do not evidence any curvature or contour projecting out
of or into the plane of the page, but rather are shown as planar.
As such, there is no explicit disclosure of surface contour on a surface
defining a portion of the clearance gap in a radial direction, and no
appropriate basis to assert that such contour would necessarily be present, as
is required for a showing of inherency. The rejection of claim 14, and of
dependent claims 24—34, as being anticipated by Kneeland, is not sustained.
Claims 15—17—Unpatentability over Naik and Liang
Claims 15—17 depend from claim 14. The Examiner does not rely on
Liang in any manner that remedies the above-noted deficiency in the
Examiner’s findings relative to claim 14. For example, the Examiner
continues to rely on fins 8 of Naik as forming a non-axisymmetric surface
contour, which we have found in regard to the anticipation rejection of claim
14 is not supported by the teachings of Naik. The Examiner does not rely on
Liang to teach such a non-axisymmetric surface contour. Accordingly, the
rejection of claims 15—17 as being unpatentable over Naik and Liang is not
sustained.
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Appeal 2015-001034
Application 12/753,211
DECISION
The Examiner’s rejections of claims 14—36 are REVERSED.
REVERSED
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