Daniel Bernard. Kupratis et al.

Patent Trials and Appeals Board

Sep 19, 2019

15420221 - (D) (P.T.A.B. Sep. 19, 2019)

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.
15/420,221 01/31/2017 Daniel Bernard Kupratis 64167US22;
67097-1876US17
8640
54549 7590 09/19/2019
CARLSON, GASKEY & OLDS/PRATT & WHITNEY
400 West Maple Road
Suite 350
Birmingham, MI 48009
EXAMINER
NGUYEN, ANDREW H
ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
09/19/2019 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 DANIEL BERNARD KUPRATIS and
FREDERICK M. SCHWARZ
Appeal 2019-000663
Application 15/420,221
Technology Center 3700
Before JENNIFER D. BAHR, LINDA E. HORNER, and
BRANDON J. WARNER, Administrative Patent Judges.
BAHR, 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 1–14 and 19–21.2 We have jurisdiction
under 35 U.S.C. § 6(b).
We REVERSE.

1 We use the word “Appellant” to refer to the “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.
2 Appellant cancelled claims 15–18 and 22–30 in an Amendment filed July
9, 2018, with the Appeal Brief. See Adv. Act. 1–2 (mailed Aug. 1, 2018).
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CLAIMED SUBJECT MATTER
The claims are directed to a geared turbofan gas turbine engine having
a turbine section including a fan turbine and a second turbine. Spec. ¶ 6.
Claim 1, reproduced below, is the only independent claim and is illustrative
of the claimed subject matter.
1. A gas turbine engine comprising:
a fan including a plurality of fan blades rotatable about
an axis;
a compressor section;
a combustor in fluid communication with the compressor
section;
a turbine section in fluid communication with the
combustor, the turbine section including a fan drive turbine and
a second turbine, wherein the second turbine is disposed
forward of the fan drive turbine and the fan drive turbine
includes a plurality of turbine rotors with a ratio between the
number of fan blades and the number of fan drive turbine rotors
is between 2.5 and 8.5; and
a speed change system configured to be driven by the fan
drive turbine to rotate the fan about the axis at a different speed
than the fan drive turbine;
wherein the fan drive turbine has a first exit area and
rotates at a first speed, the second turbine section has a second
exit area and rotates at a second speed, which is faster than the
first speed, said first and second speeds being redline speeds, a
first performance quantity is defined as the product of the first
speed squared and the first area, a second performance quantity
is defined as the product of the second speed squared and the
second area, and a performance ratio of the first performance
quantity to the second performance quantity is greater than 0.5.
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REJECTIONS3
I. Claims 1–14 and 19–21 stand rejected under 35 U.S.C. § 112(a) as
failing to comply with the enablement requirement.
II. Claims 1–14 and 19–21 stand rejected under 35 U.S.C. § 103 as
unpatentable over Suciu,4 Rosen5 or Merchant,6 and further in view of
Kurzke7 and Mattingly.8
OPINION
Rejection I—Enablement
In rejecting the claims for lack of enablement, the Examiner states that
because the ranges recited for the “performance ratio,” “gear ratio,” “bypass
ratio,” and “pressure ratio” in claims 1, 2, 6, 8, 12, 13, 19, and 20 “are not
bounded by an upper limit, each of the unbounded limitations therefore
includes numerical values . . . which range to infinity.” Final Act. 2–3. The
Examiner determines that Appellant’s “disclosure does not enable such large
values of performance ratio, gear ratio, bypass ratio, [and] pressure ratio.”
Id. at 3.
Citing Scripps Clinic & Research Foundation v. Genentech, Inc., 927
F.2d 1565 (Fed. Circ. 1991), Appellant argues that “[o]pen-ended [ranges in]

3 The Examiner withdrew a rejection of claim 11 under 35 U.S.C. § 112(b).
Ans. 2.
4 US 2006/0130456 A1, published June 22, 2006.
5 US 3,747,343, issued July 24, 1973.
6 US 2006/0179818 A1, published Aug. 17, 2006.
7 Joachim Kurzke, Fundamental Differences Between Conventional and
Geared Turbofans, Proceedings of ASME Turbo Expo 2009: Power for
Land, Sea and Air, 145–153 (2009).
8 Jack D. Mattingly, Elements of Gas Turbine Propulsion (McGraw-Hill,
Inc. 1996).
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claims are not inherently improper” and that, in assessing whether such
limitations in claims are in compliance with the enablement requirement,
“the Examiner must first determine whether ‘there is an inherent, albeit not
precisely known, upper [or lower] limit’ and the[n] secondly determine
whether ‘the specification enables one of skill in the art to approach that
limit.’” Appeal Br. 3–4. Appellant contends that “the Examiner’s
enablement analysis focuses on an irrelevant range: between the claimed
lower limit and infinity.” Id. at 4.
Appellant submits that “one of ordinary skill in the art would
recognize that performance ratios, gear ratios, bypass ratios, and pressure
ratios have inherent upper limits based on the practical physical limitations
and basic architecture of a bypass turbine engine” and that “Appellant's
disclosure is record evidence and fully supports that inherent, practical
limitations exist for each of the claimed quantities.” Id.
With respect to bypass ratio, Appellant contends that one would
understand from at least the disclosure in paragraphs 43, 46, and 60 of
Appellant’s Specification “that the basic architecture of a bypass turbine
engine requires sufficient airflow to be delivered by the fan 42 to the core
flow path C for combustion to occur and the engine to function” and that
“[t]he minimum amount of airflow required to operate the engine provides
an inherent practical upper limitation to the claimed bypass ratio.” Id. at 4–
5. Appellant adds that one would understand from Figure 1 “that the blades
42 and the flow paths B, C must fit within the surrounding structure, again,
making an infinite bypass area ratio unachievable.” Id. at 5.
With respect to gear ratio, Appellant contends that one would
understand from paragraphs 46 and 51 of Appellant’s Specification “that the
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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 ratio impractical.” Id. Appellant points out that “[a]n
infinitely high gear ratio would also require an infinitely high speed of the
turbine driving the geared architecture,” but “[t]he limited combustion
products for extraction of energy[, described in paragraph 43 of Appellant’s
Specification,] makes an infinitely high turbine speed impractical.” Id.
With respect to performance ratio, Appellant contends that “a worker
would understand that an infinitely large ratio would require the fan drive
turbine to rotate infinitely faster, or have an infinitely larger turbine exit area
compared to the second turbine”9 and that “one would recognize that an
infinite turbine exit area is unachievable.” Id. at 6 (citing Spec. ¶¶ 80, 84,
86). Thus, according to Appellant, “since both the exit area 110 and
rotational speed of the fan drive turbine 46 have practical limitations, an
infinite performance ratio is impossible.” Id.
With respect to fan drive turbine pressure ratio, Appellant contends
that one would understand from paragraphs 43 and 48 of Appellant’s
Specification “that the limited combustion products delivered to the low
pressure turbine 46 makes an infinitely high turbine pressure ratio
impractical.” Id. at 5–6.

9 Claim 1 recites that “the second turbine section has a second exit area and
rotates at a second speed.” Appeal Br. 14 (Claims App.). Therefore,
although, mathematically, either a second exit area of zero or a second speed
of zero would yield a second performance quantity of zero, and, thus, a
performance ratio of infinity, we agree with Appellant’s position that one of
skill in the art would understand that claim 1 does not cover such a
theoretical possibility.
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For the above reasons, Appellant submits that “a worker would
understand at least in view of Appellant’s disclosure that there are practical
limits to each of the claimed quantities” referenced by the Examiner in the
enablement rejection. Id. at 6.
In response, the Examiner states that “[n]othing in the cited passages
allows one of ordinary skill in the art to determine the limits for any of the
claim elements (gear ratio, turbine speed, turbine pressure ratio, turbine exit
area) and as a result the claims are not enabled.” Ans. 4. According to the
Examiner, “while an infinite value of any variable is of course unachievable,
the larger matter is that an artisan is not enabled to determine what any of
the limits of any of the claim variables may be, as the disclosure provides
insufficient guidance.” Id.
Insofar as the enablement requirement is concerned, the dispositive
issue is whether an applicant’s disclosure, considering the level of ordinary
skill in the art as of the date of the appellant’s application, would have
enabled a person of such skill to make and use the appellant’s invention
without undue experimentation. In re Strahilevitz, 668 F.2d 1229, 1232
(CCPA 1982). Factors to be considered in determining whether a disclosure
would require undue experimentation include: (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 basis of the Examiner’s enablement rejection is that the ranges for
the cited limitations are not bounded by an upper limit and, therefore,
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include numerical values that range to infinity. Final Act. 2–3. To the
extent that this determination appears to relate to the breadth of the claims,
we recognize that the limitations in claims 1, 2, 6, 8, 12, 13, 19, and 20 are
broad in that they do not expressly recite an upper boundary for the recited
performance ratio, gear ratio, bypass ratio, and pressure ratio. However, the
Examiner does not adequately explain how the breadth of these limitations
would relate to undue experimentation.
The amount of disclosure necessary to provide enablement for a range
with no upper limit depends on the particular facts of the invention, the
disclosure, and the prior art; the relevant question is whether one of ordinary
skill in the art would be able to make and/or use the claimed invention from
the disclosure in the specification without undue experimentation. In re
Fisher, 427 F.2d 833, 836 (CCPA 1970). For example, the disclosure of a
single value within an open-ended range may be sufficient when persons
skilled in the art are able to make and/or use the invention with values other
than the particular disclosed value, but is insufficient when “they are not
able to do so.” Id. The Examiner has not identified any other value less
than infinity for the recited ranges as being not enabled, and Appellant
persuasively explains why, given the context of the claimed structures, there
is an inherent upper limit that a skilled artisan would recognize as being less
than infinity.
For the above reasons, we do not sustain the rejection of claims 1–14
and 19–21 under 35 U.S.C. § 112(a).

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Rejection II—Obviousness
The Examiner finds that Suciu discloses a gas turbine engine
comprising a fan, a compressor section, a combustor, a turbine section
including a fan drive turbine (low speed/pressure turbine (LPT) 26) and a
second turbine (high speed/pressure turbine (HPT) 25). Final Act. 4; see
Suciu, Fig. 1; ¶ 14. The Examiner also finds that Suciu’s fan drive turbine
(LPT 26) includes three turbine rotors. Id. The Examiner finds that Suciu is
silent as to the ratio of the number of fan blades to the number of fan drive
turbine rotors, but determines it would have been obvious to provide Suciu
with between 6 and 13 fan blades, as taught by Rosen, to provide a desired
noise level. Id. (citing Rosen 4:35–45). The Examiner notes that the ratio of
13 fan blades to 3 fan drive turbine rotors is 4.3, which falls within the
claimed range of between 2.5 and 8.5. Id. at 4–5. As an alternative position,
the Examiner finds that Merchant teaches that the blade count in the fan is a
result-effective variable and determines that, thus, discovering the optimum
number of fan blades in Suciu involves only routine skill in the art. Id. at 5.
Thus, the Examiner determines it would have been obvious to provide Suciu
with less than 18 fan blades and a ratio of fan blades to fan drive turbine
rotors between 2.5 and 8.5. Id. Appellant does not contest the Examiner’s
findings or reasoning regarding the combination of Suciu and either Rosen
or Merchant. See Appeal Br. 7–13.
The Examiner finds that Suciu is silent as to the claimed performance
ratio of the first performance quantity to the second performance quantity
and the claimed gear reduction ratio. Final Act. 5. However, the Examiner
finds that Kurzke teaches a first performance quantity (LPT AN2) of 36.4 x
106 m2RPM2, which is 5.64 x 1010 in2RPM2, for a geared bypass engine. Id.
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(citing Kurzke 152, Table 2, col. 4). The Examiner finds that Mattingly
teaches making the second performance quantity (HPT AN2) 5 x 1010
in2RPM2. Id. (citing Mattingly 727, Table 9-16a). Using the first
performance quantity taught by Kurzke and the second performance quantity
taught by Mattingly, the Examiner finds that the performance ratio is 1.13,
which is greater than 0.5, as recited in claim 1. The Examiner also finds that
Kurzke teaches that geared turbofans may comprise gear ratios of greater
than about 2.3, namely gear ratio 3. Id. (citing Kurzke 152, Table 2). Based
on the teachings of Kurzke and Mattingly, the Examiner determines it would
have been obvious to make the performance ratio greater than 0.5 and the
gear reduction ratio greater than about 2.3 because “it has been held that
combining or simple substitution of prior art elements according to known
methods to yield predictable results renders the limitation obvious.” Id. at
5–6.
Furthermore, the Examiner finds that “Kurzke and Mattingly teach the
general conditions of the claim – that the first and second performance
quantities (AN2) were well-known results-effective variables, affecting [fuel
consumption] and that optimization of the first and second performance
quantities was known.” Id. at 6 (citing Kurzke 150–151, Figure 17;
Mattingly 726–727). Thus, the Examiner determines that “[d]iscovering the
optimum or workable ranges of the first and second performance quantities,
and thus the performance ratio, was well known in the art and would have
been obvious.” Id. at 6.
Appellant argues, persuasively, that “[t]he Examiner points to no
evidence of an associated LPT AN2 quantity in Mattingly or an associated
HPT AN2 quantity in Kurzke” and that, thus, “it is improper for the
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Examiner to assume that the HPT AN2 values allegedly disclosed by
Mattingly would be appropriate for the particular LPT of Suciu in view of
Kurzke.” Appeal Br. 9. As Appellant points out, the Examiner does not
point to any objective evidence that either Kurzke or Mattingly teaches or
suggests performance quantities for both the LPT and the HPT, much less a
ratio between such performance quantities. Id. Furthermore, “the Examiner
has not pointed to any evidence of a ratio of performance quantities being
recognized in any of the cited references.” Id.
As is evident from both Mattingly and Kurzke, there are many design
parameters (e.g., bypass ratio, pressure ratio, gear ratio) that contribute to the
performance of a turbine engine. See Mattingly 726–731; Kurzke 146–152.
Mattingly discloses a range (4–5 x 1010 in2RPM2) for what appears to be a
“typical” design value for HPT AN2. Mattingly 727. The Examiner does
not direct our attention to any disclosure in Mattingly of any LPT AN2
values associated with this range. Although Mattingly’s Table 9-16a does
not explicitly indicate engine bypass ratios associated with HPT AN2 values
in this range, Mattingly shows engine bypass ratios of 1.45 and 4.86 for Pratt
& Whitney engines introduced in 1961 and 1970, respectively, perhaps
suggesting that the HPT AN2 values may be associated with such bypass
ratios. Id., Table 9-16b. The Examiner appears to arbitrarily select from
Kurzke’s Table 2 an LPT AN2 value for an engine having a bypass ratio of
14, along with an HPT AN2 of 5 x 1010 in2RPM2 from Mattingly’s Table 9-
16a, without offering sufficient technical explanation as to how or why one
would design a turbine engine having this particular LPT AN2 value with
this particular HPT AN2 value. Given the many engine design parameters
that appear to be relevant to both the first performance quantity (LPT AN2)
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and the second performance quantity (HPT AN2), the Examiner’s
explanation that “[t]hese are two different modifications applied to two
different engine elements” and that “[t]hey are separately and explicitly
taught by their respective secondary references, and would be obvious to
apply to a gas turbine engine” is inadequate. See Ans. 4–5.
The Examiner states that “[t]he teachings of Kurzke and Mattingly are
applied directly to each variable of the claimed ratio (first performance
quantity, second performance quantity), and optimization of every variable
in the ratio directly results in optimization of the ratio.” Id. at 7. However,
even assuming that both the first performance quantity (LPT AN2) and the
second performance quantity (HPT AN2) were recognized as result-effective
variables at the time of Appellant’s invention, for the reasons discussed
above, the Examiner does not provide sufficient evidence or technical
explanation to indicate that optimizing each performance quantity
individually in a single engine would yield a performance ratio greater than
0.5 as claimed.
For the above reasons, the rejection lacks the requisite evidentiary
findings and reasoning to establish that the subject matter of claim 1 would
have been obvious. Accordingly, we do not sustain the rejection of claim 1,
or claims 2–14 and 19–21, which depend from claim 1, as unpatentable over
Suciu, Rosen or Merchant, and Kurzke and Mattingly.
DECISION
The Examiner’s decision to reject claims 1–14 and 19–21 under
35 U.S.C. § 112(a) is REVERSED.
The Examiner’s decision to reject claims 1–14 and 19–21 under
35 U.S.C. § 103 is REVERSED.
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DECISION SUMMARY
Claims
Rejected
Basis Affirmed Reversed
1–14, 19–21 § 112(a) 1–14, 19–21
1–14, 19–21 § 103 Suciu, Rosen or
Merchant, and Kurzke
and Mattingly
1–14, 19–21
Overall
Outcome
1–14, 19–21

REVERSED