Ex Parte West et al

Patent Trial and Appeal Board

Apr 28, 2016

11959975 (P.T.A.B. Apr. 28, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
111959,975 12/19/2007 James A. West
52082 7590 05/02/2016
General Electric Company
GE Global Patent Operation
3135 Easton Turnpike
Fairfield, CT 06828
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
229277 3685
EXAMINER
KIM, CRAIG SANG
ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
05/02/2016 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):
gpo.mail@ge.com
marie.gerrie@ge.com
lori.E.rooney@ge.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte JAMES A. WEST, REX A. MORGAN, LEWIS B. DAVIS, JR.,
SAM D. DRAPER, and AMIT TOPRANI
Appeal2014-004652
Application 11/959,975 1
Technology Center 3700
Before JOHN C. KERINS, EDWARD A. BROWN, and
SEAN P. O'HANLON, Administrative Patent Judges.
O'HANLON, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
James A. West et al. (Appellants) appeal under 35 U.S.C. § 134 from
the Examiner's decision rejecting claims 1-7, 11-13, 17, 18, and 20. Claims
8-10 and 14--16 are withdrawn, and claim 19 is canceled. Appeal Br. 2. We
have jurisdiction over this appeal under 35 U.S.C. § 6(b ).
1 According to the Appellants, the real party in interest is General Electric
Company. Appeal Br. 1.
Appeal2014-004652
Application 11/959,975
SUMMARY OF DECISION
We REVERSE.
SUMMARY OF INVENTION
The Appellants' invention "relates to an exhaust gas recirculation
system, and more particularly to a method and system for adjusting
turbomachine operation after exhaust gas reenters a portion of the
turbomachine." Spec. i-f 2. Claims 1 and 17 are independent. Claim 1,
reproduced below from page 10 (Claims Appendix) of the Appeal Brief, is
illustrative of the claimed subject matter:
1. A method of adjusting the operation of a turbomachine,
wherein the turbomachine generates an exhaust stream and
comprises an inlet section; the method comprising:
providing at least one exhaust gas recirculation (EGR)
system comprising: at least one EGR flow conditioning device
and at least one flow control device; wherein the EGR
recirculates the exhaust stream to the inlet section of the
turbomachine;
determining a composition of an inlet fluid; wherein the
composition comprises at least one constituent; and
adjusting an exhaust temperature setpoint of the
turbomachine based on the composition of the inlet fluid.
REFERENCES
The prior art relied upon by the Examiner in rejecting the claims on
appeal:
Kataoka US 2002/0043063 Al
Ootake US 6,843,055 B2
Super US 2005/0066659 Al
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Apr. 18, 2002
Jan. 18,2005
Mar. 31, 2005
Appeal2014-004652
Application 11/959,975
Holtman US 6,895,752 Bl
REJECTIONS
May 24, 2005
Claims 1-3, 7, 11-13, 17, 18, and 20 are rejected under 35 U.S.C.
§ 103(a) as being unpatentable over Kataoka in view of Holtman.
Claims 4 and 6 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Kataoka in view of Holtman and Ootake.
Claim 5 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Kataoka in view of Holtman and Super.
ANALYSIS
Claims 1-3, 7, 11-13, 17, 18, and 20---Kataoka in view of Holtman
Claims 1-3, 7, and 11-13
Regarding claim 1, the Examiner finds that Kataoka discloses "a
method of adjusting the operation of a turbomachine, wherein the
turbomachine (comprising compressor 1, combustor 2, and turbine 3)
generates an exhaust stream and comprises an inlet section," and "providing
at least one exhaust gas recirculation (EGR) system comprising: at least one
EGR flow conditioning device 41 b and at least one flow control device 1 O;
wherein the EGR recirculates the exhaust stream to an inlet section of the
turbomachine; [and] wherein the composition comprises the at least one
constituent (C02)." Final Act. 2-3, citing Kataoka Fig. 17. The Examiner
relies on Holtman as teaching "an electronic control unit 46 (Fig. 1) which
controls a valve in response to a sensor 4 7 which monitors the C02 content
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Application 11/959,975
of the exhaust gas." Id. at 3, citing Holtman col. 3, 11. 1-3; Fig. 1. The
Examiner further finds that "Holtman measures C02 content and adjusts the
amount ofEGR flow. When EGR flow is increased/decreased there is a
predictable change in the exhaust temperature setpoint." Id. at 7. The
Examiner concludes that it would have been obvious, to one having ordinary
skill in the art, at the time the invention was made, to modify Kataoka to
include the Holtman valve and sensor for, inter alia, "adjusting the exhaust
temperature setpoint of the turbomachine based on the composition of the
inlet fluid (where recirculation rate is controlled depending on the C02
content of the exhaust stream and where the recirculation rate directly affects
the working fluid temperature which adjusts the exhaust temperature
setpoint)" in order to "provide for a more accurate reading of the operating
conditions of the engine." Id. at 3. Additionally, the Examiner finds that
although Kataoka teaches a constant exhaust temperature setpoint, it "will be
adjusted depending on [the] inlet-fluid/fuel combination, i.e., for different
combinations of inlet-fluids and fuels, there will be a corresponding different
constant of the exhaust temperature." Adv. Act. 2.
The Appellants argue that Kataoka cannot properly be modified to
have an adjustable exhaust temperature setpoint "because Kataoka' s
principle of operation requires that the gas turbine exhaust gas temperature is
maintained substantially constant." Appeal Br. 4. The Appellants assert
"nothing in Kataoka even suggests that the constant exhaust gas temperature
is adjusted to a different constant based on a different combination of inlet
fluid and fuel." Id. at 5. Furthermore, the Appellants argue, Holtman fails
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Application 11/959,975
to cure the deficiencies of Kataoka because "Holtman, like Kataoka, is silent
as to adjusting an exhaust temperature setpoint." Id. at 7.
The Examiner responds that while Kataoka teaches that "it may be
desirable to maintain a constant temperature for maximum efficiency, actual
operations have their own constraints which prevent it from happening, and
cause deviations from the ideal conditions. Consequently, the [electronic
control unit] will measure the gathered data, including the fuel composition,
and make the necessary changes as they are needed." Ans. 3, citing Kataoka
i-f 132. The Examiner further responds that Holtman teaches "an [electronic
control unit] system that uses inputs from sensors ... and based on gathered
information diverts cooled exhaust gas into a the [sic] primary exhaust gas
or into inlet. In either case, the end result would be a different exhaust gas
temperature than without the additional cooled exhaust gas." Id., citing
Holtman col. 3, 11. 12-26.
The Appellants reply that while "Kataoka acknowledges that it may
not be possible to maintain the desired constant combustion temperature at
all times in real operation," "Kataoka states that ... the undesirable change
should be controlled to suppress a drop of the combustion temperature."
Reply Br. 2. Moreover, the Appellants argue, "[ n ]othing in ... Kataoka
teaches or suggests that a new constant or a new setpoint should be sought
because of this undesirable change in combustion temperature." Id. at 2-3.
The Appellants further argue that "any change in exhaust gas temperature in
Holtman would be incidental to Holtman's intended purpose of cooling
recirculated exhaust gas," and "[t]he Examiner does not include any
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Appeal2014-004652
Application 11/959,975
reasoning as to how or why this incidental change in exhaust gas
temperature is a teaching of the claimed invention." Id. at 4.
If a proposed modification or combination of the prior art would
change the principle of operation of the prior art invention being modified,
then the teachings of the references are not sufficient to render the claims
prima facie obvious. See In re Ratti, 270 F .2d 810 (CCP A 1959). Here, the
Examiner relies on Kataoka to teach the recited step of providing an exhaust
gas recirculation (EGR) system that recirculates a turbomachine exhaust
stream to the turbomachine inlet. Final Act. 2-3. As noted by the
Appellants, Kataoka teaches a method of operating a gas turbine that uses an
EGR system to maintain a constant exhaust gas temperature. See Appeal Br.
5, citing Kataoka i-fi-f 10, 12, and 58. According to Kataoka, as the load
demand of the gas turbine decreases, causing a temperature decrease in the
combustion chamber, the flow of (hot) recirculated exhaust to the
combustion chamber is increased to act as a counterbalance and maintain a
constant combustion chamber temperature and, therefore, a constant exhaust
gas temperature. See, e.g., Kataoka i1 58. In the event that the combustion
chamber temperature rises above the acceptable temperature tolerance,
Kataoka also provides a spray system to inject water droplets into the
combustion chamber that are vaporized to lower the combustion chamber
temperature-and, therefore, the exhaust temperature-back to the chosen
value. See, e.g., Kataoka i-fi-f 138--43.
Having set forth the gas turbine and EGR system of Kataoka, the
Examiner then proposes to modify the Kataoka system by "adjusting the
exhaust temperature setpoint of the turbomachine based on the composition
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Application 11/959,975
of the inlet fluid," relying on Holtman to teach "an electronic control unit ...
which controls a valve in response to a sensor ... which monitors the C02
content of the exhaust gas." Final Act. 3. We agree with the Appellants that
the Examiner's modification of Kataoka is improper. The basic principle of
operation of the Kataoka system is to provide a constant exhaust temperature
by controlling the combustion chamber temperature. When actual operating
conditions cause the combustion chamber to rise or fall, the Kataoka system
takes measures to counteract these deviations to keep the exhaust
temperature constant. This operation is set forth in the section of Kataoka
quoted by the Examiner in the Answer, which provides that the recirculated
exhaust flow and spray system are used to respond to a temperature
deviation; the "necessary changes" referred to by the Examiner are made to
return the exhaust temperature to the setpoint. See Ans. 2-3, quoting
Kataoka ,-r 132. Thus, Kataoka requires a single, constant exhaust
temperature setpoint, and the Examiner's modification of Kataoka to the
contrary is in error.
We further agree with the Appellants that Holtman does not teach the
setting of an exhaust temperature setpoint. While the Examiner finds that
Holtman teaches monitoring the carbon dioxide content within the
combustion chamber and controlling the recirculation flow based on the
monitored value (see Ans. 3), the Examiner has not identified within
Holtman any teaching or suggestion of controlling such flow to meet a
required exhaust temperature, that is, an exhaust temperature setpoint, as
required by claim 1.
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Application 11/959,975
The Examiner's rejection fails to adequately demonstrate that the
subject matter of independent claim 1 would have been obvious over the
combination of the Kataoka and Holtman references. The rejection of this
claim, as well as that of claims 2, 3, 7, and 11-13 depending therefrom, is
not sustained.
Claims 17, 18, and 20
Independent claim 1 7 requires inter alia "utilizing a turbomachine
operating model for determining a firing temperature of the turbomachine"
and "determining an adjustment for an exhaust temperature setpoint of the
turbomachine." See Appeal Br. 12.
With respect to the determining step, the Examiner's findings and the
Appellants' arguments are similar to those discussed supra with respect to
the determining and adjusting steps of claim 1. See Final Act. 2-3; Appeal
Br. 8; and Reply Br. 2--4. For the reasons set forth supra, we agree with the
Appellants that the Examiner's proposed modification of Kataoka is
improper.
With respect to the utilizing step, we agree with the Appellants that
the Examiner has erred by failing to address or consider the operating model
required by the claim.
The Examiner's rejection fails to adequately demonstrate that the
subject matter of independent claim 17 would have been obvious over the
combination of the Kataoka and Holtman references. The rejection of this
claim, as well as that of claims 18 and 20 depending therefrom, is not
sustained.
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Application 11/959,975
Claims 4 and 6---Kataoka in view of Holtman and Ootake
Ootake is not relied upon by the Examiner in any manner that would
remedy the deficiencies noted above with respect to the proposed
combination of Kataoka and Holtman in rendering obvious the subject
matter of claim 1. Therefore, the rejection of claims 4 and 6 is not sustained.
Claim 5-Kataoka in view of Holtman and Super
Super is not relied upon by the Examiner in any manner that would
remedy the deficiencies noted above with respect to the proposed
combination of Kataoka and Holtman in rendering obvious the subject
matter of claim 1. Therefore, the rejection of claim 5 is not sustained.
DECISION
The Examiner's decision to reject claims 1-3, 7, 11-13, 17, 18, and
20 under 35 U.S.C. § 103(a) as being unpatentable over Kataoka in view of
Holtman is reversed.
The Examiner's decision to reject claims 4 and 6 under 35 U.S.C.
§ 103(a) as being unpatentable over Kataoka in view of Holtman and Ootake
is reversed.
The Examiner's decision to reject claim 5 under 35 U.S.C. § 103(a) as
being unpatentable over Kataoka in view of Holtman and Super is reversed.
REVERSED
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