Ex Parte Plant

Patent Trial and Appeal Board

Dec 30, 2016

12769934 (P.T.A.B. Dec. 30, 2016)

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.
12/769,934 04/29/2010 Adam D. Plant 2009P22880US 8697
28524 7590 01/04/2017
SIEMENS CORPORATION
INTELLECTUAL PROPERTY DEPARTMENT
3501 Quadrangle Blvd Ste 230
EXAMINER
SUTHERLAND, STEVEN M
Orlando, EL 32817 ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
01/04/2017 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):
ipdadmin.us@siemens.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ADAM D. PLANT
Appeal 2015-003477
Application 12/769,934
Technology Center 3700
Before JOHN C. KERINS, STEFAN STAICOVICI, and LEE L. STEPINA,
Administrative Patent Judges.
KERINS, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Adam D. Plant (Appellant) appeals under 35 U.S.C. § 134(a) from the
Examiner’s final decision rejecting claims 1—8, 10-14, 16, 18, and 19. We
have jurisdiction over this appeal under 35 U.S.C. § 6(b).
We REVERSE.
THE INVENTION
Appellant’s claimed invention relates to a turbine engine assembly
and method of operating a turbine engine assembly. Claims 1,11, and 16
are independent. Claim 1 is illustrative of the claimed subject matter and is
reproduced below:
Appeal 2015-003477
Application 12/769,934
1. A turbine engine assembly for a generator, the assembly
comprising:
a turbine engine having a compressor section, a
combustor section and a turbine section, the combustor section
having a primary zone temperature (T_PZ) and the turbine
engine having a base load;
the combustor section including a combustor and a
combustor shell, the combustor shell receiving air from an exit
of the compressor section;
the combustor including a flow sleeve surrounding a
combustion zone having a hot gas flow in a direction from the
combustor toward the turbine section, and the combustor
including an outer housing surrounding the flow sleeve to
define an annular flow area for flow of air along the flow sleeve
in a direction opposite to the hot gas flow;
a variable flow restrictor extending around the flow
sleeve at an axial location of the combustion zone, the variable
flow restrictor defined by a structure extending radially inward
from the outer housing to the flow sleeve and located in the
annular flow area between the combustor shell and an inlet to
the combustor where the flow of air along the flow sleeve is
opposite to the hot gas flow both upstream and downstream of
the flow restrictor, the variable flow restrictor effecting an
increase in a pressure drop of shell air flowing from the
combustor shell to the combustor; and
a controller for operating the variable flow restrictor to
increase a pressure drop across the variable flow restrictor when
an operating load is less than the base load, wherein a flow of
shell air passing from the combustor shell to the combustor is
decreased in combination with a reduction in fuel flow to the
combustor, thereby reducing power output from the turbine
engine while maintaining the T_PZ above a T_PZ lower limit
without substantially increasing an air/fuel ratio.
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Appeal 2015-003477
Application 12/769,934
THE REJECTIONS
The Examiner has rejected:
(i) claims 1—4, 11—14, 16, and 18 under 35 U.S.C. § 103(a) as
being unpatentable over Saintsbury (US 3,952,501, issued Apr. 27, 1976)
and Iizuka (US 4,766,721, issued Aug. 30, 1998).
(ii) claims 5—8 under 35 U.S.C. § 103(a) as being unpatentable over
Saintsbury, Iizuka, and Sood (US 5,537,864, issued July 23, 1996).
(iii) claims 10 and 19 under 35 U.S.C. § 103(a) as being
unpatentable over Saintsbury, Iizuka, and Chen (US 7,107,772 B2, issued
Sept. 19, 2006).
ANALYSIS
Claims 1—4, 11—14, 16, and 18—Saintsbury/Iizuka
Claim 1 recites, in part, “a controller for operating the variable flow
restrictor to increase a pressure drop across the variable flow restrictor ...
wherein a flow of shell air passing from the combustor shell to the
combustor is decreased in combination with a reduction in fuel flow to the
combustor.” Appeal Br. 21 (Claims App.). Claims 11 and 16 include
similar limitations.
The Examiner finds that Saintsbury discloses most of the limitations
of claim 1 including a controller for operating the variable flow restrictor to
increase a pressure drop. Final Act. 3 (citing Saintsbury, col. 5,11. 9—12).
The Examiner states that when baffle B2 (variable flow restrictor) of
Saintsbury is fully opened, “a flow of shell air passing from the combustor
shell to the combustor is decreased.” Id. (citing Saintsbury, col. 5,11. 13—
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Appeal 2015-003477
Application 12/769,934
14). The Examiner relies on Iizuka for disclosing “reducing fuel flow
(figure 7b, fuel flow reduced with reduced load) in combination with
reducing compressed air flow to the combustor (reduction of air flow to
combustor with reduced load in figure 7d).” Id. The Examiner concludes
that it would have been obvious “to reduce both fuel flow and air flow to the
combustor of Saintsbury during reduced load, according to the method
taught by Iizuka, in order [to] reduce NOx formation during low load
operation.” Id. (citing Iizuka, col. 2,11. 40-47).
Appellant asserts that plate 243 of baffle B2 of Saintsbury adjusts the
relative amounts of air reaching each of the primary and secondary zones
260, 262 of the combustor, and that when Saintsbury lowers plate 243, “the
air that would have entered the primary zone is simply diverted to the
secondary zone via a series of holes.” Appeal Br. 10. Appellant argues that
the diverted air flow “does not suggest a reduction in the (total) amount of
air entering the combustor nor does it suggest a decrease in the mass flow
through the combustor.” Id.
The Examiner responds that the claims do not require reducing the
total amount of air entering the combustor. See Ans. 2. The Examiner notes
that reducing fuel flow to the combustor when air flow to one zone is
reduced as taught by Iizuka “will inherently reduce the total mass flow
through the combustor.” Id. at 3.
Appellant reiterates that “when Saintsbury’s baffle/control plate is in
the closed/down position, Saintsbury teaches that air is diverted from the
primary combustion zone into the secondary combustion zone, which
suggests that the flow of shell air, and the corresponding mass flow/mass
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Appeal 2015-003477
Application 12/769,934
flow rate, remains unchanged.” Reply Br. 4—5 (citing Saintsbury, col. 4,1.
64—col. 5,1. 3). Appellant thus argues that Saintsbury alone does not suggest
decreased flow and reduced mass flow, and that the combination of
Saintsbury and lizuka fails to teach these limitations. See id. at 7.
We agree with Appellant that plate 243 of baffle B2 in Saintsbury
does not decrease a flow of shell air passing from the combustor shell to the
combustor, as required by claim 1, and does not reduce mass flow through
the combustor when there is an increase in the pressure drop as required by
claims 11 and 16. Saintsbury discloses that baffles B2 “control the
proportion of air delivered to the primary and secondary zones through the
holes (some of which have been shown) in the combustor liner.” Saintsbury,
col. 4,11. 47—51. Thus, as Appellant correctly notes (see Reply Brief 4—5),
the amount of air will remain the same and just be diverted to different zones
of the combustor. Although we appreciate that lizuka is relied upon for
disclosing a reduction of fuel flow and air flow to a combustion zone during
partial load (see Answer 3), lizuka reduces air flow by using air bleed pipe
line 39 to bleed air from the combustion chamber. See, e.g., lizuka, col. 2,
11. 40-56; Figs. 1 and 4—7(d). The Examiner has not adequately explained
whether Saintsbury is to be modified to include bleed air lines, “according to
the method taught by lizuka” (see Final Act. 3) in order to reduce flow. Nor
does the Examiner sufficiently explain how any modification based on
lizuka would operate in conjunction with baffle B2 of Saintsbury.
The rejection of claims 1—4, 11—14, 16, and 18 as being unpatentable
over Saintsbury and lizuka is not be sustained.
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Appeal 2015-003477
Application 12/769,934
Claims 5—8—Saintsbury/Iizuka/Sood
Sood is not relied on by the Examiner to cure the deficiency noted
above with respect to the proposed combination of Saintsbury and Iizuka.
The rejection of claims 5—8 is not sustained.
Claims 10 and 19—Saintsbury/Iizuka/Chen
Chen is not relied on by the Examiner to cure the deficiency noted
above with respect to the proposed combination of Saintsbury and Iizuka.
The rejection of claims 10 and 19 is not sustained.
DECISION
The rejections of claims 1—8, 10-14, 16, 18, and 19 under 35 U.S.C.
§ 103(a) are reversed.
REVERSED
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