Ex Parte Kohlenberg et al

Patent Trial and Appeal Board

Nov 28, 2017

13340771 (P.T.A.B. Nov. 28, 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.
13/340,771 12/30/2011 Gregory A. Kohlenberg 50640US03;
67097-901PUS3
9966
54549 7590 11/30/2017
TART SON OASKFY fr OT DS/PR ATT fr WHTTNFY
EXAMINER
400 West Maple Road
Suite 350
KANG, EDWIN G
Birmingham, MI 48009 ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
11/30/2017 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 GREGORY A. KOHLENBERG,
SEAN P. ZAMORA, and FREDERICK M. SCHWARZ
Appeal 2016-004397
Application 13/340,771
Technology Center 3700
Before JENNIFER D. BAHR, JAMES P. CALVE, and
FREDERICK C. LANEY, Administrative Patent Judges.
BAHR, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Gregory A. Kohlenberg et al. (Appellants)1 appeal under 35 U.S.C.
§ 134(a) from the Examiner’s decision, set forth in the Final Action (Apr. 7,
2015, hereinafter “Final Act.”), rejecting claims 1-6, 10-13, and 15 under
35 U.S.C. § 103(a) as unpatentable over Kohlenberg (US 2009/0053058 Al,
published Feb. 26, 2009) and Rosen (US 3,747,343, issued July 24, 1973).
We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM.
1 According to the Appeal Brief (Sept. 1, 2015, hereinafter “Appeal Br.”),
the real party in interest is United Technologies Corporation. Appeal Br. 1.
Appeal 2016-004397
Application 13/340,771
THE CLAIMED SUBJECT MATTER
Claim 1, reproduced below, is the only independent claim, and is
representative of the claimed subject matter.
1. A nacelle assembly for a high-bypass gas turbine engine
comprising:
a core nacelle defined about an engine centerline axis;
a gear system driven by a core engine within said core
nacelle to drive a fan within said fan nacelle, wherein said fan
defines a corrected fan tip speed less than 1150 ft / second;
a fan nacelle mounted at least partially around said core
nacelle to define a fan bypass flow path for a fan bypass airflow;
and
a fan variable area nozzle movable relative said fan nacelle
to vary a fan nozzle exit area and adjust a fan pressure ratio of
the fan bypass airflow during engine operation, said fan pressure
ratio is less than 1.45.
DISCUSSION
The issue presented in this appeal is whether it would have been
obvious to modify Kohlenberg, in view of the combined teachings of
Kohlenberg and Rosen, to have a fan pressure ratio of less than 1.45 to make
the fan aerodynamically efficient and abate noise generation as taught by
Rosen, and to operate the fan in a range of fan tip speeds less than 1150
ft/sec. to abate noise generation as also taught by Rosen. See Final Act. 4-5,
7; Ans. 2-3; Appeal Br. 3-5.
Appellants argue that the applied references “teach away from the
proposed modification^] and do not provide a reasonable expectation of
success.” Appeal Br. 4. More specifically, Appellants contend that Rosen’s
disclosure of fixed features (i.e., fixed fan pressure ratio, fixed fan tip speed,
and fixed ratio of stator vanes to fan blades), which “do not change to tailor
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Application 13/340,771
engine operation to current operating conditions,” are “[i]n contrast” to
Kohlenberg’s disclosure of adjusting “the nozzle exit area to enable optimal
engine performance at different engine operating conditions” and “in direct
contrast to the intended operation of the Kohlenberg engine and [VAFN].”2
Id. at 4.
Rosen’s teachings with respect to fan pressure ratio and fan tip speed
are not in contrast to, or inconsistent with, Kohlenberg’s teaching of using a
VAFN to vary the area of the fan nozzle exit area to provide optimized
engine operation over a range of flight conditions. See Kohlenberg 27-
28. Kohlenberg teaches designing the fan for a particular flight condition—
typically cruise at 0.8M and 35,000 feet—and operating a VAFN to
effectively vary the fan nozzle exit area to adjust fan bypass air flow for
efficient engine operation at other flight conditions, such as landing and
takeoff. Id. In other words, Kohlenberg teaches designing the fan to
optimize engine operation for a particular flight condition (typically cruise
condition) and providing the VAFN to permit optimization of engine
operation at other flight conditions that vary from the design flight
condition. However, Kohlenberg does not specify particular fan pressure
ratio or fan tip speed values for the fan for the design flight condition.
Rosen teaches that an aerodynamically efficient fan achieving larger noise
reductions can be designed by providing a fan pressure ratio between 1.05
and less than 1.30 and fan tip speeds of around 600-800 ft/sec. (less than
sonic tip speed). Rosen 1:50—66, 3:15-18. It would have been obvious to
design Kohlenberg’s fan using such a combination of fan pressure ratio and
2 Appellants use the acronym “VAFN” for the “fan variable area nozzle”
used to change the bypass flow path area. Spec. ^ 2.
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Appeal 2016-004397
Application 13/340,771
fan tip speed in order to attain the advantages taught by Rosen (i.e.,
aerodynamic efficiency and improved noise abatement) for particular flight
conditions (e.g., cruise conditions), while still using Kohlenberg’s VAFN to
vary the fan nozzle exit area to adjust fan bypass air flow for efficient engine
operation at other flight conditions, such as landing and takeoff. The fact
that Rosen does not teach using a VAFN like Kohlenberg to optimize engine
operation for other flight conditions would not have discouraged skilled
artisans from designing Kohlenberg’s fan using the fan pressure ratio and
fan tip speed taught by Rosen for optimized performance at the design flight
condition. Thus, the references do not teach away from the proposed
combination.
Appellants argue that “modification of Kohlenberg to include Rosen’s
fixed fan pressure ratio, fan tip speed and fixed ratio between stator vanes
and fan blades would eliminate the need for a variable area fan nozzle and
therefore no rational reason to support the proposed modification is present.”
Appeal Br. 4. We do not agree with Appellants. Modification of
Kohlenberg to include the fan pressure ratio, fan tip speed, and ratio of stator
vanes to fan blades as taught by Rosen to optimize engine performance at a
particular flight condition, such as cruise, would not eliminate the need for a
variable area fan nozzle to adjust fan bypass air flow for efficient engine
operation at other flight conditions, such as landing and takeoff.
Appellants submit that the Examiner is impermissibly ignoring
Rosen’s teachings with regard to the ratio of stator blades to fan blades.
Appeal Br. 5; see Rosen 4:13-17 (teaching that, in addition to the low tip
speed and pressure ratio range between 1.05 and 1.3, “the number of stator
vanes should be less than the number of fan blades and preferably the count
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Appeal 2016-004397
Application 13/340,771
should be substantially 1:2 and the axial spacing between the rotor and stator
should be 2 rotor blades widths”). This is not the case. See Ans. 3 (the
Examiner’s proposed modification includes incorporating all fan parameters,
including those directed to fan blade count, that contribute to the noise
reduction taught by Rosen).
Appellants additionally argue that “[mjodification of Kohlenberg to
include the variable pitch fan blades instead of the VAFN completely
changes and alters the intended configuration of the disclosed Kohlenberg
device.” Appeal Br. 5. This argument does not identify error in the
rejection because the Examiner does not propose modifying Kohlenberg to
replace the VAFN with variable pitch fan blades. See Ans. 4 (emphasizing
the rejection proposes modifying Kohlenberg’s fan to operate with a fan
pressure ratio of less than 1.45 and a fan tip speed of less than 1150 ft/sec.,
with a fan blade count from 6-13, as taught by Rosen, while maintaining
Kohlenberg’s VAFN “to enable efficient engine operation at other than the
design flight condition”).
For the above reasons, Appellants’ arguments do not apprise us of
error in the Examiner’s determination that it would have been obvious to
modify Kohlenberg, in view of the combined teachings of Kohlenberg and
Rosen, to have a fan pressure ratio to make the fan aerodynamically efficient
and abate noise generation as taught by Rosen, and to operate the fan in a
range of fan tip speeds less than 1150 ft/sec. to abate noise generation as also
taught by Rosen. Accordingly, we sustain the rejection of independent claim
1, as well as dependent claims 2-6, 10-13, and 15, for which Appellants rely
solely on the arguments presented for claim 1 (Appeal Br. 5), as
unpatentable over Kohlenberg and Rosen.
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Application 13/340,771
DECISION
The Examiner’s decision rejecting claims 1-6, 10-13, and 15 is
AFFIRMED.
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)(l)(iv).
AFFIRMED
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