UNITED TECHNOLOGIES CORPORATION

Patent Trials and Appeals Board

Apr 29, 2020

15022025 - (D) (P.T.A.B. Apr. 29, 2020)

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.
15/022,025 03/15/2016 Matthew Andrew Hough 67097-2618PUS1;73729US02 9180
54549 7590 04/29/2020
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
EXAMINER
LEGENDRE, CHRISTOPHER RYAN
ART UNIT PAPER NUMBER
3745
NOTIFICATION DATE DELIVERY MODE
04/29/2020 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 MATTHEW ANDREW HOUGH
Appeal 2019-005155
Application 15/022,025
Technology Center 3700
Before JAMES P. CALVE, WILLIAM A. CAPP, and
JEREMY M. PLENZLER, Administrative Patent Judges.
PLENZLER, 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, 7–12, and 17–20. We have
jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies the real party in interest as United
Technologies Corporation. Appeal Br. 1.
Appeal 2019-005155
Application 15/022,025

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CLAIMED SUBJECT MATTER
The claims are directed to gas turbine engine cooling. Claim 1,
reproduced below, is illustrative of the claimed subject matter:
1. A gas turbine engine component array comprising:
first and second components each having a platform, the
platforms are arranged adjacent to one another and provide a gap
circumferentially between axially lateral faces of the adjacent
platforms; and
a seal is arranged circumferentially between the first and
second components and in engagement with the platforms to
obstruct the gap, a cooling hole is provided in the seal and is in
fluid communication with the gap, the cooling hole has an
increasing taper toward the gap, wherein the lateral faces overlap
the cooling hole in a circumferential direction, the cooling hole
having a circumferential width that is larger than the width of the
gap.
REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Weidner US 4,650,394 Mar. 17, 1987
Green US 5,382,135 Jan. 17, 1995
Mercadante US 5,415,526 May 16, 1995
Liang US 8,382,424 B1 Feb. 26, 2013
Giri US 2013/0028713 A1 Jan. 31, 2013
Morris US 2014/0099189 A1 Apr. 10, 2014

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Application 15/022,025

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REJECTIONS2
Claims 1, 2, 4, 5, 7, 12, 17, and 20 are rejected under 35 U.S.C. § 103
as being unpatentable over Weidner and Giri.
Claims 8–11, 18, and 19 are rejected under 35 U.S.C. § 103 as being
unpatentable over Weidner, Giri, and Morris.
Claims 1–3 are rejected under 35 U.S.C. § 103 as being unpatentable
over Green, Weidner, Giri, and Mercadante.
OPINION
Background
Claims 1 and 17 are independent. Claim 1 is directed to “[a] gas
turbine engine component array” having “a seal . . . arranged
circumferentially between the first and second components” with “a cooling
hole is provided in the seal . . . and is in fluid communication with [a] gap”
formed between adjacent components. The cooling hole “has an increasing
taper toward the gap.” Claim 17 is directed to “[a] method of cooling a gas
turbine engine component” like that recited in claim 1. To achieve the
cooling, claim 17 recites “flowing cooling fluid from the cavity through a
cooling hole in a seal provided between the adjacent components” and
“diffusing the cooling fluid through the cooling hole . . . to create a cooling
film in the gap.”
Appellant’s Figures 2A, 2B, and 3A are reproduced below.

2 The Examiner withdrew the rejections under 35 U.S.C. § 112 in the
Advisory Action. Adv. Act. 1.
Appeal 2019-005155
Application 15/022,025

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“Figure 2A is a perspective view of the airfoil having the disclosed cooling
passage.” Spec. ¶ 29. “Figure 2B is a plan view of the airfoil illustrating
directional references.” Id. ¶ 30. “Figure 3A . . . illustrate[s] a seal arranged
with respect to a [component] platform.” Id. ¶ 31. The Specification
explains that “the cooling hole 102 includes an increasing taper toward the
gap 104 to diffuse the fluid flow through the cooling hole 102 as it exits the
seal 77 into the gap 104.” Id. ¶ 48. As a result of the diffusion caused by
tapered cooling hole 12, “the velocity of the cooling fluid through the
hole 102 is slowed, such that the cooling fluid will linger within the gap 104
forming a boundary layer of cooling film.” Id.
Weidner/Giri and Weidner/Giri/Morris Rejections
The Examiner finds that Weidner teaches the majority of features
recited in claims 1 and 17 including “a cooling hole (i.e., any one of
orifices 106,108,112,114 - Figure 4).” Final Act. 4, 6. The Examiner,
however, finds that Weidner does not teach “the cooling hole ha[ving] an
increasing taper toward the gap” (claim 1), and “diffusing the cooling fluid
through the cooling hole on a gas path flow side of the seal opposite the
cavity to create a cooling film in the gap provided between adjacent
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Application 15/022,025

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platforms of the components” (claim 17). Id. at 4, 7. The Examiner finds
that Giri teaches these features. Id. at 4, 7. Appellant does not dispute these
findings. See Appeal Br. 3–4. Rather, Appellant disputes the Examiner’s
rationale for modifying Weidner’s cooling hole in view of Giri’s teachings.
Id.
As for the proposed combination of Giri’s teachings with those of
Weidner, the Examiner reasons that “[i]t would have been obvious . . . to
include shaping the hole to have a taper” in Weidner “for the purpose of
permitting metering of the cooling flow and/or increased cooling of the
seal.” Final Act. 4, 7. Appellant responds that such a modification “would
not have been obvious at least because it would render Weidner less
effective for its intended purpose.” Appeal Br. 3. Specifically, Appellant
contends that “Giri’s conical hole 430 would render Weidner less effective
at cooling the critical region 88b by reducing the velocity of the cooling air.”
Id. Appellant explains that “Weidner describes the importance of cooling air
exiting the orifices 106, 108, 112, 114 with a high velocity radial
component.” Id. (citing Weidner 9:54–64).
In response, the Examiner “agrees that diffusion of a fluid/gas/air
involves decreasing speed thereof,” but disagrees that Weidner “disclose[s]
that a ‘high velocity’ is required to achieve its intended purpose.” Ans. 3–4.
The Examiner explains that “Weidner is silent as to any required
degree/magnitude of speed of the cooling air” and “mere diffusion of the
cooling air of Weidner would not necessarily produce an unsuitable speed
thereof.” Id. at 4. The Examiner finds that “diffusion of the cooling air of
Weidner can produce a distribution of the cooling air across a larger area of
Weidner region 88b.” Id. The Examiner reasons that “[a] skilled artisan,
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Application 15/022,025

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recognizing that the overall effectiveness of a cooling scheme is determined
by (at least) both the speed of the cooling fluid/gas/air and the magnitude of
the area that is subjected to the cooling fluid/gas/air, would be able to
balance both of these variables in order to achieve effective cooling.” Id.
at 4–5.
Appellant has the better position. The portion of Weidner cited by
Appellant explains that “[a]s the working medium gases are flowed along
the annular flow path outwardly of the rotor blades, the gases tend to sweep
the cooling air through the gap G and to push the cooling air outwardly
toward the orifice plate 94.” Weidner 9:50–54. That is, the working
medium gases oppose the inward flow of the cooling air. Weidner explains
that “[t]he orientation of the openings [106, 108, 112, 114] and the flow of
air through the openings provides a radial component of velocity to the
cooling air.” Id. at 9:54–56. To compensate for the effects of the working
medium gases, “[t]he velocity of the cooling air in the radial direction
imparts a momentum to the cooling air that causes a column of cooling air to
extend radially inwardly in the gap G, counteracting the pushing, sweeping
effect of the working medium gases.” Id. at 9:56–61.
As noted above, there is no dispute that the Examiner’s proposed
modification to Weidner’s teachings would result in a decrease in velocity
for the cooling air passing through openings 106, 108, 112, 114. See Ans. 3.
Even if “Weidner is silent as to any required degree/magnitude of speed of
the cooling air” and “mere diffusion of the cooling air of Weidner would not
necessarily produce an unsuitable speed thereof,” as the Examiner
determines (Ans. 4), that does not mean that a velocity reduction in Weidner
would have been obvious “for the purpose of permitting metering of the
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cooling flow and/or increased cooling of the seal,” as the Examiner reasons
(Final Act. 4, 7). It seems at least equally, if not more, likely that the
velocity reduction proposed by the Examiner would result in decreased
cooling in Weidner’s system because that cooling air velocity is necessary to
overcome the working medium gases acting against the cooling air flow into
the space occupied by the working medium gases. Weidner 9:50–54.
Without further explanation or evidence, the Examiner has failed to establish
sufficiently that one skilled in the art would have been motivated to modify
Weidner’s system to shape the hole to have a taper, which the Examiner
agrees would reduce the cooling air velocity (Ans. 3), to permit metering of
the cooling flow and/or increase cooling of the seal when Giri’s taper 430 is
used to meter a leakage flow, and Weidner relies on the cooling air velocity
to overcome the working medium gases to cool components.
For at least these reasons, we do not sustain the Examiner’s decision
to reject claims 1, 2, 4, 5, 7–12, and 17–20.
Green/Weidner/Giri/Mercadante Rejection
The Examiner’s rejection based on obviousness over Green, Weidner,
Giri, and Mercadante relies on similar findings and rationale regarding the
use of the teachings from Weidner and Giri discussed above. See, e.g., Final
Act. 13; Ans. 6. We do not sustain the Examiner’s decision to reject claims
1–3 for reasons similar to those discussed above.
CONCLUSION
The Examiner’s rejections are reversed.
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Application 15/022,025

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DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 2, 4, 5, 7,
12, 17, 20
103 Weidner, Giri 1, 2, 4, 5, 7,
12, 17, 20
8–11, 18, 19 103 Weidner, Giri,
Morris
8–11, 18, 19
1–3 103 Green, Weidner,
Giri, Mercadante
1–3
Overall
Outcome
1–5, 7–12,
17–20
REVERSED