United Technologies Corporation

Patent Trials and Appeals Board

Feb 28, 2020

14818392 - (D) (P.T.A.B. Feb. 28, 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.
14/818,392 08/05/2015 Robert Russell Mayer 67097-1747PUS2;61306US02 4887
54549 7590 02/28/2020
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
EXAMINER
SUNG, GERALD LUTHER
ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
02/28/2020 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 ROBERT RUSSELL MAYER, GEORGE J. KRAMER, and
PAUL W. PALMER
____________

Appeal 2019-003492
Application 14/818,392
Technology Center 3700
____________

Before ANTON W. FETTING, BRADLEY B. BAYAT, and
TARA L. HUTCHINGS, Administrative Patent Judges.

BAYAT, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Appellant1 seeks our review under 35 U.S.C. § 134 from the
Examiner’s final rejection claims 1–7, which are all the claims pending in
the application. 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 “United Technologies Corporation” as the
real party in interest. Appeal Br. 1.
Appeal 2019-003492
Application 14/818,392

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CLAIMED SUBJECT MATTER
Appellant’s “disclosure relates to a gas turbine engine mid turbine
frame bearing support.” Spec. ¶ 2. Claim 1, reproduced below, is
illustrative of the subject matter on appeal.
1. A gas turbine engine comprising:
high and low pressure turbines;
a mid-turbine frame arranged axially between the high
and low pressure turbines;
a bearing operatively supported by a support structure;
an inner case secured to the support structure and
including a first conical member; and
a bearing support to which the bearing is mounted, the
bearing support including a second conical member that is
secured to the first conical member at a joint, the first and
second conical members arranged radially inward of the joint,
the joint provided at a plane perpendicular to a rotational axis of
the high and low pressure turbines, a first axial side on one side
of the plane, and a second axial side on another side of the
plane opposite the one side, the first and second conical
members are arranged on the first axial side;
a fan;
a compressor section fluidly connected to the fan, the
compressor comprising a high pressure compressor and a low
pressure compressor;
a combustor fluidly connected to the compressor section;
a turbine section fluidly connected to the combustor, the
turbine section comprising:
a high pressure turbine coupled to the high
pressure compressor via a first shaft;
a low pressure turbine coupled to the low pressure
compressor via a second shaft;
a geared architecture interconnects between the
second shaft and the fan; and
wherein the gas turbine engine is a high bypass geared
aircraft engine having a bypass ratio of greater than six (6).
Appeal Br. 10 (Claims App.).
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Application 14/818,392

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REJECTION
Claims 1–7 are rejected under 35 U.S.C. § 112 (Pre-AIA), first
paragraph, as failing to comply with the enablement requirement.

OPINION
Enablement
Claim 1 recites the limitation “a bypass ratio of greater than six (6),”
claims 2, 4, and 5 recite “a pressure ratio that is greater than 5,” and claims
3, 4, 6, and 7 recite “a gear reduction ratio of greater than 2.5:1.” Appeal
Br. 10–12 (Claims App.).
The Examiner rejects claims 1–7 for failing to comply with the
enablement requirement. The Examiner asserts:
All three limitations are open ended ranges which approach
infinity. A review of the specification shows that the Applicant
only nominally discloses the features without disclosing how
the bypass ratio is achieved above 6, the pressure ratio above 5,
and the gear ratio greater than 2.5:1. Paragraph [0020] states
that the bypass ratio may be greater than 10:1 without further
explanation and that the gear reduction ratio may be greater
than 2.1:1. The claimed scope covers bypass ratios, gear
reduction ratios, and pressure ratios approaching infinite and
not currently in existence.
Final Act. 2–3. According to the Examiner, “the breadth of the claims
covers any performance increases in bypass ratio, gear reduction ratios, and
pressure ratios of the turbine and therefore is found to be expansive. . . . No
known working examples exist in the prior art disclosing the upper bounds
of the claimed ranges and the inventor provides no direction.” Id. at 3–4.
“Thus, [the Examiner concludes that] the quantity of experimentation
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needed to make and use the invention at the upper bounds of the claimed
scope is unduly high.” Id. at 4.
Alleging error in the rejection, Appellant argues that “the rejection
fails to consider the claims in the proper context” because “one of ordinary
skill in the art would recognize that each of the claimed quantities has an
inherent upper limit based on the practical physical limitations and basic
architecture of a bypass turbine engine.” Appeal Br. 4–5 (citing Scripps
Clinic & Research Foundation v. Genentech, Inc., 927 F.2d 1565 (Fed. Cir.
1991)). With respect to bypass ratio, Appellant argues that one would
understand that an inherent upper limit exists in view of paragraphs 16, 18,
and 19 of Appellant’s disclosure. Id. at 5 (“One would understand from at
least these portions of Appellant’s Specification that the basic architecture of
a bypass turbine engine requires sufficient airflow to be delivered by the fan
section 22 to the core airflow path for combustion to occur and the engine to
function.”).
With respect to gear reduction ratio, Appellant argues that in light of
paragraphs 18, 20, and 43 of the Specification, “[o]ne would understand that
the fan must have some speed to deliver sufficient airflow to the core engine
so that the engine may operate and for the fan to produce thrust, making an
infinitely high gear reduction ratio impractical.” Appeal Br. 6 (“The
turbines 46, 54 rotationally drive the respective low speed spool 30 and high
speed spool 32 in response to the expansion. The limited combustion
products for extraction of energy makes an infinitely high turbine speed
impractical.”).
With respect to turbine pressure ratio, paragraph [0020]
discloses: “Low pressure turbine 46 pressure ratio is pressure
measured prior to inlet of low pressure turbine 46 as related to
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the pressure at the outlet of the low pressure turbine 46 prior to
an exhaust nozzle.” Paragraph [0043] discloses: “The core
airflow is compressed by the low pressure compressor 44 then
the high pressure compressor 52, mixed and burned with fuel in
the combustor 56, then expanded over the high pressure turbine
54 and low pressure turbine 46.” One would understand that the
limited combustion products delivered to the low pressure
turbine 46 makes an infinitely high turbine pressure ratio
impractical. Accordingly, one of ordinary skill in the art would
recognize that each of the claimed ratios have an inherent
practical and physical upper limit.

Id. at 6.
Responding to Appellant’s arguments, “the Examiner acknowledges
that open ended claims are not inherently improper,” but asserts that “the
specification merely nominally recites such limitations without any
explanation on what the practical limit is and how to approach that practical
limit.” Ans. 5 (“Appellant’s specification provides little to no guidance as to
how to make and use an apparatus at the upper bounds of the claimed
range.”). According to the Examiner, “though the Appellant’s claims are
drawn to mechanical inventions, it does not follow the Appellant is absolved
from the requirement to provide an enabling specification.” Id. at 6.
Appellant’s arguments are persuasive.
Determining enablement is a question of law based on underlying
factual findings. In re Vaeck, 947 F.2d 488, 495 (Fed. Cir. 1991). The
determination that “undue experimentation” would have been needed to
make and use the claimed invention is not a single, simple factual
determination. Rather, it is a conclusion that may be reached by weighing
relevant factual considerations including:
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(1) the quantity of experimentation necessary, (2) the amount of
direction or guidance presented, (3) the presence or absence of
working examples, (4) the nature of the invention, (5) the state
of the prior art, (6) the relative skill of those in the art, (7) the
predictability or unpredictability of the art, and (8) the breadth
of the claims.
In re Wands, 858 F.2d 731, 737 (Fed. Cir. 1988). The initial burden is on
the Examiner to set forth “a reasonable explanation” of why the Examiner
believes a person of ordinary skill in the art, given what the Specification
discloses, would be unable to practice the invention without “undue
experimentation.” See In re Wright, 999 F.2d 1557, 1561–62 (Fed. Cir.
1993).
Although the Examiner reproduces these considerations in the
rejection (Final Act. 3) and the Answer (Ans. 3–4), the Examiner does not
address the Wands factors in light of Appellant’s disclosure, by performing
the requisite weighing. For instance, the Examiner does not explain
adequately why an artisan would not recognize that the upper limit for each
of the claimed ranges is bounded by known practical structural and physical
limits of a gas turbine engine. “The Examiner does not provide any
reasoning why a skilled worker would be unable to recognize that each of
the claimed ratios has an inherent upper limit based on the practical physical
limitations and basic architecture of a bypass turbine engine in view of at
least the previously cited portions of Appellant’s disclosure.” Reply Br. 2.
[T]he Examiner does not dispute that a skilled worker would
understand that the basic architecture of a gas turbine engine
limits each of the claims ratios, including the following:
(a) sufficient airflow needs to be delivered by the fan section to
the core airflow path for combustion to occur and the engine to
function; (b) the fan blades and the flow paths must fit within
the surrounding structure; (c) the fan must rotate with at least
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some speed to deliver sufficient core airflow into the bypass
and core flow paths for compression to occur and for the engine
to produce thrust; and (d) the limited combustion products
delivered to the turbine for extraction of energy limits turbine
speeds[.]
Id.
In fact, as Appellant points out, “the Examiner concedes that
towards the bottom of the ratio, e.g. bypass ratios of 10, such a
disclosure would likely be appropriate and such a ratio would likely
be adequately enabled by the specification.” Reply Br. 3 (quoting
Final Act. 6); see also Appeal Br. 5. Yet, the Examiner explains that
“these claimed ratios extend from the lower bound to the upper bound
which may include bypass ratios of 100, 1000, 10000, etc.” Final
Act. 6. To the extent that this determination appears to relate to the
breadth of the claims, we recognize that the limitations at issue here
are broad in that they do not expressly recite an upper boundary for
the recited bypass ratio, gear reduction ratio, and turbine pressure ratio
ranges.
However, the Examiner has not adequately explained how the
breadth of these limitations would relate to undue experimentation in
the context of Appellant’s invention. The Examiner concluded that
the claimed subject matter would require undue experimentation
because the Specification does not provide “what the practical limit is
and how to approach that practical limit” (Ans. 5), but did not
articulate any findings or analysis to show that a person of ordinary
skill in the art would have been unable to make and use the claimed
invention without undue experimentation, given the basic architecture
and confines of a gas turbine engine. We agree with Appellant that,
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the physical and structural limitations of a gas turbine engine
construction necessarily impose a maximum bound, for example, on
the bypass ratio that can be achieved; we agree with Appellant that
infinity is not a practical limitation for the recited features.
Accordingly, we do not sustain the rejection of claims 1–7 as failing
to comply with the enablement requirement.

CONCLUSION
The decision to reject claims 1–7 is reversed.
In summary:
Claims
Rejected
35 U.S.C. § Basis Affirmed Reversed
1–7 112, first
paragraph
Enablement 1–7

REVERSED