Ex Parte Plant et al

Patent Trial and Appeal Board

May 13, 2016

12685185 (P.T.A.B. May. 13, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/685, 185 0111112010
28524 7590 05/17/2016
SIEMENS CORPORATION
INTELLECTUAL PROPERTY DEPARTMENT
3501 Quadrangle Blvd Ste 230
Orlando, FL 32817
FIRST NAMED INVENTOR
Adam D. Plant
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.
2009P00371US01 6866
EXAMINER
WALTHOUR, SCOTT J
ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
05/1712016 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, CHRISTOPHER R. OLIVERI,
BRUCE H. CARPENTER, DAMIEN G. TEEHAN, and
DAVID D. EL WOOD
Appeal2014-004523
Application 12/685,185
Technology Center 3700
Before JENNIFER D. BAHR, WILLIAM A. CAPP and
AMANDA F. WIEKER, Administrative Patent Judges.
CAPP, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants seek our review under 35 U.S.C. § 134 of the final
rejection of claims 1, 3-7 and 9-20. We have jurisdiction under 35 U.S.C.
§ 6(b).
We AFFIRM.
Appeal2014-004523
Application 12/685, 185
THE INVENTION
Appellants' invention relates to gas turbine power generation systems.
Spec. 1. Claim 1, reproduced below, is illustrative of the subject matter on
appeal.
1. A method of reducing power output in an electric power
generation system comprising:
providing an air compressor configured to receive ambient air
at an intake section and generate pressurized air flow for output
therefrom, the compressor including a set of controllable inlet
guide vanes for selectively throttling the ambient air taken into the
compressor;
configuring a combustion chamber in the system to receive a
combination of at least a portion of the pressurized air flow output
from the compressor and fuel for combustion of the fuel therein
and output of exhaust comprising pressurized combustion gas;
positioning a gas turbine section to receive the pressurized
combustion gas for expansion within the turbine section to
generate mechanical power;
coupling a generator to receive the mechanical power and
convert the mechanical power into electric power;
operating the system at a relatively high steady state level of
power output, at which steady state level the combustion chamber
has a characteristic minimum flame temperature for which
exhausted combustion gas is characterized by a predetermined
constituent volumetric percentage ofNOx or CO;
turning down the power being output by the turbine section by
extracting a portion of the pressurized air flow generated by the
compressor before entry into the combustion chamber, said
portion equal to at least three percent of the pressurized air flow
being output from the air compressor, the step of turning down the
power by extracting said portion of the pressurized air flow
including maintaining flame temperature to be no less than the
characteristic minimum flame temperature in the combustion
chamber when the power being output is reduced at least 45
percent relative to the relatively high steady state level of power
output of the system; and
2
Appeal2014-004523
Application 12/685, 185
after extracting, further turning down the power by
recirculating said portion of the pressurized air flow through the
compressor intake section to mix said portion with received
ambient air upstream of the compressor whereby the density of air
flowing into the combustion chamber is reduced, effectively
reducing the mass flow of oxygen to the combustion chamber
while maintaining flame temperature to be no less than said
characteristic minimum flame temperature in the combustion
chamber when the power being output is reduced at least
45percent relative to the relatively high steady state level of power
output of the system so that the combustion chamber has said
characteristic minimum flame temperature for which exhausted
combustion gas is characterized by said predetermined constituent
volumetric percentage ofNOx or CO.
THE REJECTIONS
The Examiner relies upon the following as evidence in support of the
rejections:
Arar
Andrew
Nichols
Leachman
Thatcher
Berry
us 6,027 ,304
US 6,226,974 Bl
US 6,779,346 B2
US 2006/0059919 Al
US 2007 /0204625 Al
US 2007/0271929 Al
Feb.22,2000
May 8, 2001
Aug. 24, 2004
Mar. 23, 2006
Sep. 6,2007
Nov. 29, 2007
The following rejections are before us for review:
1. Claims 1, 3, 9-11, 15, and 18-20 are rejected under 35 U.S.C.
§ 103(a) as being unpatentable over Leachman, Thatcher, and Nichols.
2. Claim 4 is rejected under 35 U.S.C. § 103(a) as being unpatentable
over Leachman, Thatcher, Nichols, and Arar.
3. Claims 5-7 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Leachman, Thatcher, Nichols, and Andrew.
3
Appeal2014-004523
Application 12/685, 185
4. Claim 12 is rejected under 35 U.S.C. § 103(a) as being
unpatentable over Leachman, Thatcher, Nichols, and Applicant-Admitted
Prior Art.
5. Claim 13 is rejected under 35 U.S.C. § 103(a) as being
unpatentable over Leachman, Thatcher, Nichols, and Berry.
6. Claim 14 is rejected under 35 U.S.C. § 103(a) as being
unpatentable over Leachman, Thatcher, Nichols, and Applicant-Admitted
Prior Art.
7. Claim 16 is rejected under 35 U.S.C. § 103(a) as being
unpatentable over Leachman, Thatcher, Nichols, and Andrew.
8. Claim 17 is rejected under 35 U.S.C. § 103(a) as being
unpatentable over Leachman, Thatcher, Nichols, and Berry.
Claim 1
OPINION
Unpatentability of Claims 1, 3, 9-11, 15, and 18-20
over Leachman, Thatcher, and Nichols
The Examiner finds that Leachman discloses all of the elements of
claim 1 except for the controllable inlet guide vanes, turning down the power
by extracting air from the compressor, and the flame temperature limitations.
Final Action 4-6. The Examiner relies on Thatcher as disclosing
controllable inlet guide vanes and turning down the power output by
extracting pressurized air flow from the compressor. Id. at 5-6. The
Examiner concludes that it would have been obvious to a person of ordinary
skill in the art at the time of the invention to include controllable inlet guide
vanes in Leachman's system. Id. at 5. According to the Examiner, a person
of ordinary skill in the art would have done this to control the load on the
4
Appeal2014-004523
Application 12/685, 185
gas turbine unit. Id. The Examiner further concludes that it would have
been obvious to extract air from Leachman's compressor as taught by
Thatcher. Id. at 6. According to the Examiner, a person of ordinary skill in
the art would have done this to control the load on the gas turbine and also to
raise the inlet temperature of the compressor which further limits the mass
flow across the compressor. Id.
The Examiner relies on Nichols as teaching flame temperature
maintenance as claimed. Id. at 7. The Examiner concludes that it would
have been obvious to a person of ordinary skill in the art at the time the
invention was made to incorporate Nichols' teaching of flame temperature
maintenance into the combined teachings of Leachman and Thatcher. Id.
According to the Examiner, a person of ordinary skill in the art would have
done this to operate a gas turbine engine with low emissions. Id.
Appellants traverse the Examiner's rejection by first arguing that
Thatcher uses controllable inlet guide vanes for a different purpose than
turning down power. Appeal Br. 9. In response, the Examiner states that
Thatcher teaches that inlet bleed heat allows a turbine operator to bleed the
discharge air of the turbine compressor and recirculate the bleed air back to
the compressor inlet. Ans. 2. The Examiner directs our attention to the
following passage from Thatcher.
Closure of the inlet guide vanes, which control the flow of air to
the turbine compressor, is another common method of
decreasing the mass flow across the gas turbine, which, in tum,
may be used to control or limit turbine load.
Thatcher i-f 6, Ans. 2. The Examiner further explains that Thatcher teaches
that it was common practice at the time of the invention to limit the mass
flow and therefore, the turbine load, by manipulating the bleed heat and inlet
5
Appeal2014-004523
Application 12/685, 185
guide vanes. Ans. 2-3. The Examiner disagrees with Appellants'
contention that Thatcher's teachings must be limited only to the context of
maintaining a maximum level load across changing ambient conditions.
In reply, Appellants reiterate their initial argument that Thatcher's
teaching is directed to keeping a gas turbine operation at a maximum level
and does not teach "turning down power." Reply Br. 2.
Appellants' argument is not persuasive for several reasons. First, we
agree with the Examiner that Thatcher teaches the general principle that
decreasing the mass flow across the gas turbine by closing inlet guide vanes
controls or limits turbine load, i.e., reduces power. Ans. 2-3. Second,
Appellants' position is belied by statements in the Background of The
Invention section of their Specification effectively admitting that it was
known to use inlet guide vanes to reduce power output. See Spec. 2 ("air
flow from the gas turbine compressor may be throttled via inlet guide vanes
to reduce the amount of power generated"). 1 Finally, it is well settled that it
is not necessary for the prior art to serve the same purpose as that disclosed
in Appellants' Specification in order to support the conclusion that the
claimed subject matter would have been obvious. See In re Linter, 458 F.2d
1013, 1016 (CCPA 1972). "Common sense teaches ... that familiar items
may have obvious uses beyond their primary purposes." KSR Int 'l Co. v.
Teleflex Inc., 550 U.S. 398, 420 (2007). For this reason, "[a] reference may
be read for all that it teaches, including uses beyond its primary purpose." In
1 Elsewhere in the Background of The Invention section, Appellants admit
that the extent to which inlet guide vanes can be used to throttle down air
flow while sustaining necessary flame temperatures is about 3 0 to 3 8 percent
of power output at specified ambient temperatures. Spec. 2-3.
6
Appeal2014-004523
Application 12/685, 185
re lvfouttet, 686 F.3d 1322, 1331 (Fed. Cir. 2012), citing KSR, 550 U.S. at
418--421.
Appellants argue that a person of ordinary skill in the art would not
have combined Leachman and Thatcher because they are inconsistent with
each other, i.e., they "teach[] away." Appeal Br. 10-11.2 Appellants argue
that Thatcher teaches that the use of inlet guide vanes "reduces thermal
efficiency," while Leachman improves thermal efficiency. Id. at 10.
According to Appellants, Thatcher discourages use of bleed heat because it
adversely affects the efficiency of the gas turbine engine. Id. at 11.
Appellants argue that Leachman teaches away from use of bleed air when
turning down power and that Thatcher teaches away from the use of bleed
air to control a gas turbine to operate a desired maximum level load across
changing ambient conditions without exceeding the maximum load level.
Id.
In response, the Examiner states that, arguments of efficiency aside,
Leachman teaches the method steps of extracting compressor air and
recirculating it back to the compressor and Thatcher teaches that the result of
such a step is a decrease in power. Ans. 4. In other words, "both references
are concerned with ... the operation of a gas turbine while operating with a
turndown in power, regardless of efficiency." Id. The Examiner states that
Thatcher also teaches that use of inlet bleed heat and controllable inlet guide
vanes were both commonplace features of gas turbine engines at the time of
the invention and that both were useful for turning down power. Id.
2 "[T]he teachings of each reference are inconsistent with the combination
which would be required to reject claim 1." Appeal Br. 11
7
Appeal2014-004523
Application 12/685, 185
\Ve think the Examiner's position on this issue is the more persuasive
one. The Examiner's citation to the prior art shows that, at the time of the
invention, the effects of variations in input air flow, temperature, and density
on turbine power output were well known and well understood. See, e.g., id.
Appellants have not established persuasively that a person of ordinary skill
in the art would not have found it obvious to combine the teachings of
Leachman and Thatcher, or would not have readily perceived the benefit of
doing so. Moreover, we are not persuaded by Appellants' "teaching away"
argument. "[I]n general, a reference will teach away if it suggests that the
line of development flowing from the reference's disclosure is unlikely to be
productive of the result sought by the applicant." In re Gurley, 27 F.3d 551,
553 (Fed. Cir. 1994). However, a reference does not teach away if it merely
expresses a general preference for an alternative invention but does not
"criticize, discredit, or otherwise discourage" investigation into the invention
claimed. In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir. 2004). Appellants do
not bring to our attention any language from Leachman that criticizes,
discredits or discourages the use of inlet guide vanes to control turbine
output. 3
3 Similarly, we have considered Appellants' argument that the Examiner is
guilty of using impermissible hindsight in making the instant rejection.
Appellants argue:
[I]t is urged that the rejection results from a search of missing
pieces in primary references and assimilation of secondary
references for the purpose of finding pieces of steps for
reassembly with use of hindsight. To this end, it appears that
the rejection parses features of claim 1 into components, finds
these in a piecemeal identification among numerous references,
and then asserts that the particular claimed combination is
obvious based on general statements taken out of distinguishing
8
Appeal2014-004523
Application 12/685, 185
Appellants argue that "the Thatcher reference simply does not
disclose using bleed heat for turning down the power of a gas turbine
engine." Appeal Br. 11. Appellants contend that a person of ordinary skill
in the art would not take Thatcher's limited disclosure of using bleed heat to
operate a turbine engine at a desired maximum level loaded across changing
ambient conditions and apply it to turning down the power of the turbine by
45 percent. Id. at 12-3 (citing Thatcher i16).
The Examiner responds that "Leachman teaches inlet bleed heat and
Thatcher teaches the result of using inlet bleed heat ... to limit turbine load,
and therefore such use of inlet bleed heat is not taken out of the context in
which inlet bleed heat is discussed by Thatcher." Ans. 4. The Examiner
also notes that "neither Leachman nor Thatcher are relied on for teaching
turning down the power of the turbine by 45 percent ... [because] Nichols
discloses this particular limitation." Id.
We are unpersuaded by Appellants' argument because Appellant has
not established persuasively that Thatcher's teaching of using inlet bleed
heat to limit load is inapplicable when turning down turbine power. As the
contexts .... It is submitted that the spirit of the inventive
concept has become lost in the effort to parse method steps into
specific subcomponents in order to find features which then
must be combined in a piecemeal manner to reconstruct the
invention.
Appeal Br. 13-14. In view of the teachings of the prior art reflecting the
well-known aerodynamic and thermodynamic principles of power
generation using gas turbine engines, some of which is admitted in
Appellant's Background section, and the inferences and creative steps that a
person of ordinary skill in the art would employ, we find Appellants'
hindsight argument to be without merit. KSR Int 'l Co. v. Teleflex Inc., 550
U.S. 398, 418 (2007).
9
Appeal2014-004523
Application 12/685, 185
Examiner correctly notes, the obviousness rejection does not rely on
Thatcher as disclosing the particular percentage claimed.
Next, Appellants argue that Nichols has no disclosure of recirculating
bleed air into a compressor. Appeal Br. 14. In response, the Examiner
points out that Nichols expressly discloses the use of inlet bleed heat. Ans. 6
(citing Nichols, col. 1, 11. 43-53). In the instant case, we do not find
Appellants' argument persuasive, as the Examiner relies on the combination
of Leachman and Thatcher to supply this claim limitation. Final Action 5-6.
Non-obviousness cannot be established by attacking references individually
where the rejection is based upon the teachings of a combination of
references. In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986); In re
Keller, 642 F.2d 413, 425 (CCPA 1981).
Next, Appellants argue that neither Leachman, Thatcher, nor Nichols
disclose turning down the power in the claimed range while maintaining the
characteristic minimum flame temperature. Appeal Br. 14-15 (arguing that
the prior art lacks "turning down the power ... by extracting a portion of the
pressurized air flow ... equal to at least three percent of the pressurized air
flow being output from the air compressor ... including maintaining flamer
temperature . . . and further turning down the power by recirculating said
portion of the pressurized air flow through the compressor ... while
maintaining flame temperature to be no less than said characteristic
minimum flame temperature in the combustion chamber when the power
being output is reduced at least 45 percent"). In their brief, Appellants'
characterize the claimed range of power reduction as "45 percent of the
relative high steady state level of power output." Id. at 15.
10
Appeal2014-004523
Application 12/685, 185
In response, the Examiner points out that the claimed range of power
reduction is not reduced to 45 percent of the steady state level of power
output as argued by Appellants, but rather that claim 1 only requires that
power is reduced by "at least 45 percent relative to the relatively high steady
state level of power output of the system," e.g., this language is interpreted
to mean "reduced by 45 percent and not to 45 percent relative to a maximum
load level." Ans. 5; Claims App., Claim 1. The Examiner states that the
claim limitation is met by a disclosure in Nichols which explains that the
load range associated with a disclosed mode of operation is 50 percent
to 100 percent load. Ans. 6 (citing Nichols, col. 1, 11. 48-50).
We agree with the Examiner's interpretation of the claim language,
given the recitation in claim 1 that the power "is reduced at least 45 percent
relative to the relatively high steady state level." Appeal Br., Claims App.,
Claim 1. Furthermore, the Examiner's finding of fact on regarding Nichols'
disclosure is supported by a preponderance of the evidence.
Finally, Appellants argue that the prior art fails to disclose the
quantitative requirements in claim 1 directed to: (1) extracting at least three
percent of the pressurized air flow output from the air compressor; and (2)
maintaining flame temperature when the power output is reduced at least 45
percent. Appeal Br. 14. Appellants argue that Nichols only discloses
loading down to about 90 percent while maintaining low emission
operations. Id. at 15. Appellants argue that Nichols' disclosure of loading
ranges of 50-100 percent does not apply because low emission operations
are not maintained throughout this range. Id.
In response, the Examiner states that Leachman discloses extracting
3.3-8.7% of pressurized air from the compressor, and that Nichols does
11
Appeal2014-004523
Application 12/685, 185
""Cl Cl •• "" t. ",..I mamtam 11ame temperature 1or 1ow emisswn operatwns m tue citeu range.
Ans. 7-8 (citing Leachman i-fi-f 19, 36; citing Nichols, col. 1, 11. 43-53).
As between Appellants and the Examiner, we find that the Examiner
has interpreted the prior art correctly. Specifically, we agree with the
Examiner's understanding of Leachman, which explicitly discloses a bleed
air requirement of at least three percent. Leachman i-f 3 6 ("[A] 3 0° F.
(16.7° C.) increase in the inlet air temperature reduces the CDP bleed
requirement from about 8.7% to about 3.3% of total engine airflow.").
Further, the Examiner relies on Nichols' disclosure that in a premix
operating mode, which produces "[ o ]ptimum emissions" and operates at 50-
100% load, operation occurs at the "combustion-reference-temperature
design point." Nichols, col. 1, 11. 43-50. The Examiner also relies on
Nichols' disclosure that both inlet guide vanes and inlet bleed heat are used
to maintain combustion temperature for low emissions operation. Id. at
col. 1, 11. 51-53. Therefore, we agree with the Examiner that "Nichols'
operating range of 50-100% [load] is applicable to the method taught by
Leachman in view of Thatcher wherein the turbine power is turned down by
using the very same steps claimed by Appellant, and that by the use of these
steps flame temperature may also be maintained for optimum or low
emissions operation," as taught by Nichols. Ans. 7-8.
The Examiner's findings of fact with respect to the rejection of
claim 1 are supported by a preponderance of the evidence and the
Examiner's legal conclusion ofunpatentability is supported by sound
reasoning. We sustain the Examiner's unpatentability rejection of claim 1.
12
Appeal2014-004523
Application 12/685, 185
Claim 3
Appellants do not argue for the separate patentability of claim 3 apart
from arguments presented with respect to claim 1 which we have previously
considered. 4 Appellants have waived the right to argue the separate
patentability of this claim. See 37 C.F.R. § 41.37(c)(l)(iv)(2015). We
sustain the unpatentability rejection of claim 3.
Claim 9
Claim 9 depends from claim 1 and adds the limitation: "wherein the
steps of extracting and recirculating said portion of the pressurized air flow
to tum down the power being output by the turbine section include
maintaining flame temperature to be no less than said characteristic
minimum flame temperature in the combustion chamber when the power
being output is reduced at least 50 percent relative to the one hundred
percent rated maximum power output of the system." Claims App.
Appellants traverse the rejection by arguing that Nichols' reference to
operating at 50 percent power does not require adherence to the flame
temperature requirement of the claim. Appeal Br. 24. We disagree for
essentially the same reasons discussed above in connection with claim 1 in
connection with operating at 50-100 percent power. See Nichols, col. 1,
11. 43-53. We sustain the unpatentability rejection of claim 9.
Claim 10
Claim 10 depends from claim 9 and adds the limitation: "wherein,
with the power turned down while maintaining the flame temperature to be
4 Although the Appeal Brief states that claims 3, 11, and 19 depend from
claim 19, this appears to be a typographical error, in that these claims
depend from claim 1. Appeal Br. 24-25.
13
Appeal2014-004523
Application 12/685, 185
no less than said characteristic minimum flame temperature in the
combustion chamber, the exhausted combustion gas comprises a constituent
volumetric percentage ofNOx or CO which does not exceed said
predetermined volumetric percentage corresponding to the relatively high
steady state level of power operation output of the system." Claims App.
Appellants contend that, due to its dependency on claim 9, claim 10 requires
that the foregoing limitation must be met with the power turned down at
least 50 percent relative to the one hundred percent rated maximum power
output of the system. Appeal Br. 24. Appellants argue that Nichols fails to
disclose this limitation. Id. at 25.
In response, the Examiner states as follows:
Examiner notes that Appellant's claimed recitation regarding
volumetric percentages ofNOx or CO is in the context of the
power turned down while maintaining flame temperature.
Leachman in view of Thatcher, further in view of Nichols
teaches the turning down of the power while maintaining flame
temperature for low emissions operation. Nichols, as discussed
above, further teaches the premix operating mode enables low
and optimum emissions. While Nichols does not explicitly
discuss volumetric percentages, Examiner notes that the
claimed recitation is met by Nichols teaching of maintaining
flame temperature at and near the combustion-reference-
temperature design point wherein optimum emissions are
generated (Nichols, Col. 1, 11. 43-47). Furthermore, Nichols is
discussing the operation of a DLN (dry low-NOx) combustor
(Nichols, Col. 1, 1. 11 ), which implies that the emissions
Nichols is concerned about are at least related to the amount of
NOx generated during the premix operating mode. Nichols
further teaches that at lower loads (that is, lower than 90-92%
of base load) with gas turbines operating without variable inlet
guide vanes, the combustor reference temperature will decrease
below the required value for optimum DLN system operation.
If Nichols is disclosing optimum emissions within the premix
operating range, and that flame temperature is maintained
14
Appeal2014-004523
Application 12/685, 185
specifically for achieving such low emissions operation, and
that a combustor reference temperature below a certain value is
undesirable with regard to emissions, it is reasonable to
conclude that the operation of Leachman in view of Thatcher
further in view of Nichols is such that the exhausted
combustion gas comprises an optimum volumetric percentage
ofNOx which meets the claimed recitation. Nichols teaches the
use of variable inlet guide vanes with inlet bleed heat (which
method steps are used by Leachman in view of Thatcher),
which help to maintain combustor reference temperature, that it
is desirable not to let the combustor reference temperature dip
too low in order to keep emissions low, and that the premix
mode optimizes emissions and maintains combustor
temperature in a range for low emissions operation. These
teachings render claim 10 obvious.
Ans. 9-10.
Appellants do not claim any specific quantitative parameter ofNOx
and CO emissions for either claims 1, 9, or 10. See Claims App., Claims 1,
9, 10. Instead, claim I merely recites that the system, when it is operated at
a "relatively high steady state level of power output," exhibits a
characteristic minimum flame temperature and that, at such temperature, the
exhausted combustion gas is characterized by a predetermined constituent
volumetric percentage ofNOx and CO. Id. Claims 9 and 10 merely modify
this requirement so that it applies when the power is reduced by 50 percent
instead of 45 percent. Claims App.
Under the circumstances, we find the Examiner's reasoning and
analysis to be persuasive and we adopt the Examiner's findings, conclusion,
and underlying rationale as our own. Accordingly, we sustain the
unpatentability rejection of claim 10.
15
Appeal2014-004523
Application 12/685, 185
Claim 11
Claim 11 depends directly from claim 1 and is not separately argued.
Appellants have waived the right to argue the patentability of this claim. See
37 C.F.R. § 41.37(c)(l)(iv)(2015). Accordingly, we sustain the
unpatentability rejection of claim 11.
Claim 15
Claim 15 is an independent claim that is substantially similar scope to
independent claim 1 and is rejected over the same combination of references
as claim 1. Claims App., Final Action 9-12. In traversing the rejection of
claim 15, Appellants raise essentially the same arguments that we have
previously considered and found unpersuasive with respect to claim 1.
Thus, for essentially the same reasons previously discussed in
connection with claim 1, we sustain the Examiner's unpatentability rejection
of claim 15.
Claims 18 and 19
Claims 18 and 19 depend directly from claim 15 and are not
separately argued. We sustain the rejection of claims 18 and 19. 37 C.F.R.
§ 41.37(c)(l)(iv).
Claim 20
Claim 20 depends from claim 19 and adds the limitation: "wherein,
with the power turned down while maintaining said characteristic minimum
flame temperature in the combustion chamber, the exhausted pressurized
combustion gas consists of a volumetric percentage ofNOx or CO which
does not exceed the predetermined volumetric percentage corresponding to
one hundred percent rated maximum power output of the system." Claims
App. Appellants suggest that the Examiner failed to address claim 20 in the
16
Appeal2014-004523
Application 12/685, 185
final rejection. Appeal Br. 25. Appellants do not raise an argument for the
patentability of this claim other than perhaps to note that the Examiner's
rejection may rely on the Nichols reference in a manner similar to that of
claim 10 and then simply argues that the claimed subject matter is "simply
not disclosed in this reference." Id.
In response, the Examiner states that claim 20 was addressed in the
Final Action at paragraph 16, subparagraphs ee-hh. Ans. 10.
We do not consider that Appellants have advanced an argument for
the separate patentability of claim 20. See 37 C.F.R. § 41.37(c)(l)(iv); see
also In re Lovin, 652 F.3d 1349 (Fed. Cir. 2011) (Rule 41.37 requires more
than recitation of the claim elements and a naked assertion that the elements
are not found in the prior art). Otherwise, we note that claim 20 claims
subject matter that is substantially similar in scope to that of claim 10 and
find the Examiner's findings, conclusion, and underlying rationale with
respect to claim 10 to be equally persuasive with respect to claim 20.
Accordingly, we sustain the unpatentability rejection of claim 20.
Unpatentability of Claim 4
over Leachman, Thatcher, Nichols, and Arar
Appellants do not argue for the separate patentability of claim 4 apart
from arguments presented with respect to claim 1 which we have previously
considered. Appeal Br. 26. We sustain the unpatentability rejection of
claim 4.
Unpatentability of Claims 5-7
over Leachman, Thatcher, Nichols, and Andrew
Claims 5 and 6
Appellants argue claim 5 and state that claim 6 stands or falls with
claim 5. Appeal Br. 26-27; See 37 C.F.R. § 41.37(c)(l)(iv) (2015).
17
Appeal2014-004523
Application 12/685, 185
Claim 5 depends from claim l and contains the limitation: "further
including adjusting the inlet guide vanes to throttle down pressurized air
flow, relative to the relatively high steady state operation, through the
compressor while inserting said portion of the air flow into the compressor
intake section for mixing with received ambient air." Claims App.
Appellants argue that the prior art fails to disclose the use of inlet guide
vanes and recirculating a portion of the pressurized air flow to tum down
power at least 45 percent while maintaining characteristic minimum flame
temperature as claimed. Appeal Br. 26.
The Examiner responds that, as previously pointed out with respect to
the rejection of claim 1, Leachman in view of Thatcher teaches the turning
down of power by extracting and recirculating compressor air to the inlet of
the compressor and Nichols teaches the maintenance of a characteristic
minimum flame temperature within a range of operating between 50-100
percent. Ans. 10.
Appellants' arguments do not identify sufficiently any purported
Examiner error that has not been addressed already with respect to claim 1.
The Examiner's position, which is elaborated more fully in connection with
the rejection of claim 1, and our own previous discussion of claim 1, is the
correct position on this issue and we sustain the rejection of claims 5 and 6
for the previously stated reasons.
Claim 7
Claim 7 depends from claim 6 and contains the limitation: "wherein
the combination of adjusting the inlet guide vanes and inserting said portion
of the air flow into the compressor intake section reduces the output power
of the power generation system to at least 50 percent of the rated maximum
18
Appeal2014-004523
Application 12/685, 185
power." Claims App. Appellants argue that the Examiner's rejection side
steps the limitations of the base claim which requires turning down the
power while maintaining no less than the characteristic minimum flame
temperature. Appeal Br. 27.
In response, the Examiner once again directs our attention to the
previous discussion of claim 1 where Leachman in view of Thatcher teaches
inlet bleed heat to reduce the output power of the power generation system
and Nichols teaches that systems using both inlet bleed heat and variable
guide vanes routinely operate in a range of 50-100 percent load. Ans. 11. In
addition, the Examiner relies on Andrew as disclosing the use of inlet bleed
heat and variable inlet guide vanes. Id. The Examiner also finds that 50
percent power tum down is merely part of a "workable range" and that
extracted compressor air is a result-effective variable that increases or
decreases the output power of a gas turbine system. Id. at 12. The Examiner
concludes that it would have been obvious to a person of ordinary skill in the
art at the time the invention was made to, by routine experimentation, vary
both the extraction of compressor air and the position of the inlet guide
vanes in order to find the workable range of power output which may be
achieved by manipulating those two variables. Ans. 11-12 (citing In re
Aller, 220 F.2d 454, 456 (CCPA 1955); MPEP § 2144.05 I l(A)).
Appellants' arguments have been previously considered in connection
with the rejection of other claims, including claim 1. We find the
Examiner's position to be supported by a preponderance of the evidence and
that the Examiner conclusion of unpatentability is well founded. We sustain
the rejection of claim 7.
19
Appeal2014-004523
Application 12/685, 185
Unpatentability of Claim 12
over Leachman, Thatcher, Nichols, and Applicant-Admitted Prior Art
Appellants do not argue for the separate patentability of claim 12
apart from arguments presented with respect to claim 1 which we have
previously considered. Appeal Br. 26. We sustain the unpatentability
rejection of claim 12.
Unpatentability of Claim 13
over Leachman, Thatcher, Nichols, and Berry
Appellants' traverse to the rejection of claim 13 falls with claim 1.
Appeal Br. 28.
Unpatentability of Claim 14
Leachman, Thatcher, Nichols, and Applicant-Admitted Prior Art
Appellants' traverse to the rejection of claim 14 falls with claim 1.
Appeal Br. 28.
Unpatentability of Claim 16
over Leachman, Thatcher, Nichols, and Andrew
Claim 16 depends from claim 15 and adds the limitation: "further
including adjusting the inlet guide vanes to throttle down pressurized air
flow, relative to the relatively high steady state operation, through the
compressor while inserting said portion of the air flow into the compressor
intake section for mixing with received ambient air." Claims App.
Appellants argue that no combination of the prior art results in maintaining
flame temperature to be no less than the characteristic minimum flame
temperature in the combustion chamber when the power being output is
reduced at least 45 percent relative to the relatively high steady state level of
power output of the system. Appeal Br. 17-18. According to Appellants,
the prior art merely discloses use of inlet guide vanes and recirculating a
20
Appeal2014-004523
Application 12/685, 185
portion of the pressurized air flow, but not in a manner which results in
turning down the power at least 45 percent while maintaining characteristic
minimum flame temperature. Id.
In response, the Examiner directs our attention to the discussion in
support of the rejection of claim 1, which is directed to the identical issue.
Ans. 12. We agree with the Examiner that Appellants' challenge to the
rejection of claim 16 plows no new ground from what we previously
considered and discussed above with respect to claim 1. We sustain the
rejection of claim 16.
Unpatentability of Claim 17
over Leachman, Thatcher, Nichols, and Berry
Appellants' traverse to the rejection of claim 17 falls with claim 1.
Appeal Br. 28.
DECISION
The decision of the Examiner to reject claims 1, 3-7, and 9-20 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)(l )(iv).
AFFIRMED
21