Eric Norster et al.

Patent Trials and Appeals Board

Aug 2, 2019

12988152 - (D) (P.T.A.B. Aug. 2, 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.
12/988,152 04/05/2011 Eric Norster 410001-545PUS/302221 8165
27799 7590 08/02/2019
Cozen O'Connor
277 Park Avenue, 20th floor
NEW YORK, NY 10172
EXAMINER
NGUYEN, ANDREW H
ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
08/02/2019 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):
patentdocket@cozen.com
patentsecretary@cozen.com
patentsorter@cozen.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte ERIC NORSTER, HOLGER HUITENGA and
REINER BRINKMANN
____________________

Appeal 2019-000538
Application 12/988,152
Technology Center 3700
____________________

Before PHILLIP J. KAUFFMAN, JEREMY M. PLENZLER, and
ALYSSA A. FINAMORE, Administrative Patent Judges.

PLENZLER, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Appellants seek our review under 35 U.S.C. § 134(a) of the
Examiner’s Decision rejecting claims 13–22, 24–26, and 28. We have
jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

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Application 12/988,152

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CLAIMED SUBJECT MATTER
Claims 13 and 17 are independent, with claims 14–16 and 25
depending ultimately from claim 13; and claims 18–22, 24, 26, and 28
depending ultimately from claim 17. Claim 13 is reproduced below:
13. A method for operating a premix burner for gas turbines,
comprising:
injecting a gas-air mixture into a flame chamber as main
fuel via a swirler and a quantity of main nozzles;
injecting a first partial stream of a diffusion fuel centrally
into the flame chamber radially inside the swirler by a quantity
of first nozzles having a first orientation at an inclination to a
longitudinal axis of the premix burner and arranged in a burner
bottom radially between the longitudinal axis of the premix
burner and the swirler and configured as one of a bore, a groove,
and a longitudinal slit; and
injecting a second partial stream of the diffusion fuel
centrally into the flame chamber radially inside the swirler by a
quantity of second nozzles having a second orientation arranged
in the burner bottom parallel to the longitudinal axis of the
premix burner and radially between the quantity of first nozzles
and the swirler and configured as one of a bore, a groove, and a
longitudinal slit,
wherein the first orientation and the second orientation are
different; and
wherein the premix burner comprises twice as many
second nozzles as first nozzles.
REJECTION
Claims 13–22, 24–26, and 28 are rejected under 35 U.S.C. § 103(a) as
unpatentable over Norster (US 6,532,726 B2, issued Mar. 18, 2003);
Krockow (US 4,589,260, issued May 20, 1986); Mosbacher (US
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Application 12/988,152

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2007/0234735 A1, published Oct. 11, 2007); and Nilsson (US 2008/0041060
A1, published Feb. 21, 2008).1
OPINION
Claim 13 recites “injecting a first partial stream of a diffusion fuel . . .
by a quantity of first nozzles having a first orientation at an inclination to a
longitudinal axis of the premix burner” and “injecting a second partial
stream of the diffusion fuel . . . by a quantity of second nozzles having a
second orientation arranged . . . parallel to the longitudinal axis of the
premix burner.” Claim 17 similarly recites “a plurality of inclined diffusion
nozzles . . . configured to inject a first partial stream of diffusion fuel at an
inclination to the longitudinal axis of the premix burner” and “a plurality of
axial diffusion nozzles . . . configured to inject a second partial stream of the
diffusion fuel parallel to the longitudinal axis of the premix burner and
transverse to the main fuel flow in the flame chamber.”
The Examiner finds that Norster’s pilot jets 25 correspond to the
recited “first nozzles” and pilot jets 32 correspond to the recited “second
nozzles.” Final Act. 3. The Examiner acknowledges that Norster does not
teach pilot jets 25 disposed at an angle as required by the claims, and finds
that “it was well known in the art that pilot fuel injection holes/bores may
[be] oriented at different angles in order to impart a desired flow direction
and enhance mixing, as taught [by] Mosbacher (para 33, 36, 39–40).” Id. at
4. The Examiner reasons that “[i]t would have been obvious to one of
ordinary skill in the art at the time of the invention to angle/incline the first

1 On pages 2–3 of the Final Office Action, the Examiner rejected claims 13–
16, 18–22, 25 and 26 under 35 U.S.C. § 112, second paragraph. These
rejections were withdrawn in the Examiner’s Answer. Ans. 2–3.
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Application 12/988,152

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nozzles injecting a first stream of fuel in Norster . . . to a longitudinal axis of
the burner in order to enhance mixing, as taught by Mosbacher.” Id. The
Examiner further explains that “[i]t has been held that combining or simple
substitution of prior art elements according to known methods to yield
predictable results renders the limitation obvious (see MPEP 2141 (III))”
and, “[i]n this case, angling/inclining fuel injection holes yields predictable
results.” Id. at 4–5.
Appellants respond that “[t]here is no reason to reconfigure the
arrangement in Norster in view of Mosbacher.” Appeal Br. 11. Appellants
contend that “rearranging the nozzles in Norster would destroy the principle
of operation as depicted in Figs. 2 and 3.” Id. at 9. Appellants have the
better position.
The Examiner’s rationale is speculative, at best. The Examiner
provides a reason, generally, to use an angled or inclined injection hole (e.g.,
“to enhance mixing”) in Mosbacher’s system. Indeed, Mosbacher teaches
angled orifices 148 provide axial, radial, and tangential momentum to the
syngas injected therethrough to provide enhanced mixing with the natural
gas introduced through orifices 122. Mosbacher ¶ 40, Fig. 8. As shown in
Figure 8, orifices 122 are arranged radially along combustor nozzle 146,
whereas angled orifices 148 are arranged circumferentially. The enhanced
mixing of the syngas and natural gas is not simply the result of angled
orifices 148, but instead is the result of the orientation and position of angled
orifices 148 delivering the syngas relative to orifices 122 injecting the
natural gas.
In contrast, jets 25 and 32 of Norster are arranged differently than
Mosbacher’s orifices. Compare Norster, Fig. 3, with Mosbacher, Fig. 8.
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There is insufficient basis to establish that modifying Norster’s pilot jets 25
to be angled or inclined in some unspecified manner would produce
enhanced mixing. Norster specifically explains that “liquid pilot fuel is
injected from pilot jets 25 into the pre-chamber 13 in an axial direction
parallel, or approximately parallel, to the central longitudinal axis 21, where
it mixes with air 15 exiting the swirler passages 14.” Norster, 5:46–50.
Based on the explanation set forth in the rejection, we do not know
why one skilled in the art would have reason to believe that enhanced
mixing would be achieved in the modified system of Norster. The Examiner
provides no explanation as to how Norster’s modified system would
function to provide the enhanced mixing. Although Mosbacher discloses
that passages may have a variety of radial and tangential injection angles
(Mosbacher ¶¶ 33, 36, 39–40), the Examiner does not identify, nor do we
discern, any disclosure in Mosbacher that better mixing can be achieved by
configuring some fuel passages (nozzles) to be at a first angle relative to the
longitudinal axis and other passages to be at a second, different angle. In
other words, Mosbacher provides evidence for the general assertion that
nozzles may inject at a variety of angles, but the Examiner provides no
explanation as to why this supports the more specific concept that better
mixing can be achieved by having a first set of nozzles injecting at one angle
relative to longitudinal axis and a second set at a different angle.
Because the Examiner’s conclusory assertion is unsupported by
evidence of record, it does not provide sufficient basis for the proposed
modification of Norster’s pilot jets 25. Although the Examiner additionally
asserts that such a modification is a simple substitution, that reasoning, too,
for at least similar reasons, is deficient.
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Based on the record before us, the Examiner has failed to establish
sufficiently that one skilled in the art would have modified Norster’s pilot
jets 25 in the manner proposed.
Therefore, we do not sustain the rejection of claims 13–22, 24–26, and
28 under 35 U.S.C. § 103(a) as unpatentable over Norster, Krockow,
Mosbacher, and Nilsson.
DECISION
We REVERSE the Examiner’s decision to reject claims 13–22, 24–26,
and 28 under 35 U.S.C. § 103(a) as unpatentable over Norster, Krockow,
Mosbacher, and Nilsson.

REVERSED