Volkswagen AG

Patent Trials and Appeals Board

Nov 13, 2020

2020000887 (P.T.A.B. Nov. 13, 2020)

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.
15/148,583 05/06/2016 Peter Bach 1901.1010 8472
23280 7590 11/13/2020
Davidson, Davidson & Kappel, LLC
589 8th Avenue
22nd Floor
New York, NY 10018
EXAMINER
SLAWSKI, MAGALI P
ART UNIT PAPER NUMBER
1721
NOTIFICATION DATE DELIVERY MODE
11/13/2020 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):
ddk@ddkpatent.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte PETER BACH and SAMUEL YEW
Appeal 2020-000887
Application 15/148,583
Technology Center 1700
Before ROMULO H. DELMENDO, JEFFREY B. ROBERTSON, and
SHELDON M. MCGEE, Administrative Patent Judges.
ROBERTSON, Administrative Patent Judge.
DECISION ON APPEAL1

1 This Decision includes citations to the following documents: Specification
filed May 6, 2016 and amended on November 8, 2018 (“Spec.”); Final
Office Action mailed February 21, 2019 (“Final Act.”); Appeal Brief filed
August 29, 2019 (“Appeal Br.”) (The Appeal Brief does not contain page
numbers after the first page. As such, our reference to page numbers is from
the pages as consecutively numbered following page 1.); Examiner’s
Answer mailed September 18, 2019 (“Ans.”); and Reply Brief filed
November 11, 2019 (“Reply Br.”).
Appeal 2020-000887
Application 15/148,583

2
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the
Examiner’s decision to reject claims 1 and 4–17. Appeal Br. 5.3 We have
jurisdiction under 35 U.S.C. § 6(b).
We affirm.
CLAIMED SUBJECT MATTER
Appellant states that the invention relates to a method for adjusting an
operating gas flow in a fuel cell system, as well as a fuel cell system for
carrying out the method. Spec. ¶ 2. Claim 1, the only independent claim on
appeal, is reproduced below, and is illustrative of the claimed subject matter
(Appeal Br., Claims Appendix 10):
1. A method for adjusting an operating gas flow in a fuel cell
system, the fuel cell system including a fuel cell stack, a
supply path for feeding operating gas to the fuel cell stack, an
exhaust gas path for removing the operating gas from the fuel
cell stack, as well as a recirculation line, including a conveyor
for conveying flow of the operating gas, the recirculation line
connecting the supply path and the exhaust gas path to each
other, the method comprising the following steps:
measuring a pressure p1 and a temperature T1 in the supply
path upstream from a junction point between the recirculation
line and the supply path;
measuring a pressure p2 and a temperature T2 in the
recirculation line upstream from the junction point;
measuring a pressure p3 and a temperature T3 in the supply
path downstream from the junction point;

2 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42(a). Appellant identifies Volkswagen Aktiengesellschaft and
Audi Aktiengesellschaft, as the real parties in interest. Appeal Br. 2.
3 Claims 2 and 3 have been cancelled. Appeal Br. 2.
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Application 15/148,583

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determining a recirculation ratio as a function of
parameters T1, T2, T3, p1, p2 and p3; and
adjusting the operating gas flow through the recirculation
line as a function of the recirculation ratio.
REFERENCES
The prior art relied upon by the Examiner is:
Name Reference Date
Clawson et al.
hereinafter
“Clawson”
US 2003/0170518 A1 September 11, 2003
Guenther et al.
hereinafter
“Guenther”
US 2010/0104898 A1 April 29, 2010
Katano et al.
hereinafter “Katano”
US 2013/0202979 A1 August 8, 2013
Mazumder et al.
hereinafter
“Mazumder”
US 2014/0144124 A1 May 29, 2014
REJECTIONS
1. The Examiner rejected claims 1 and 4–144 under 35 U.S.C.
§ 103 as unpatentable over Guenther and Mazumder. Final
Act. 3–9.
2. The Examiner rejected claim 15 under 35 U.S.C. § 103 as
unpatentable over Guenther, Mazumder, and Clawson. Final
Act. 9–10.

4 Although the Examiner does not explicitly mention claim 14 in the
statement of rejection or in the body of the rejection, it is clear the Examiner
intended to reject claim 14. Final Act. 1. Appellant appears to understand
the Examiner’s rejection applies to claims 1 and 4–14. Appeal Br. 2. Thus,
the Examiner’s error is harmless.
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Application 15/148,583

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3. The Examiner rejected claims 16 and 17 under 35 U.S.C. § 103
as unpatentable over Guenther, Mazumder, Clawson, and
Katano. Final Act. 10–11.

OPINION
Rejection 1
Appellant does not present separate arguments with respect to the
claims subject to this rejection. See Appeal Br. 3–8. Accordingly, we select
claim 1 as representative for disposition of this rejection. 37 C.F.R.
§ 41.37(c)(1)(iv).

The Examiner’s Rejection
In rejecting claim 1 over Guenther and Mazumder, the Examiner
found Guenther discloses a fuel cell system including a fuel cell stack 22
with a recirculation conduit 30, and a merging position 18, which is a
junction point between the recirculation conduit or recirculation line and the
supply path. Final Act. 3–4 citing Guenther ¶¶ 9, 16, 17; Fig. 1. The
Examiner found Guenther discloses a flow control valve that may be
controlled by suitable control algorithms to adjust operating gas flow. Id. at
4 citing Guenther ¶ 17. The Examiner found Guenther discloses the ratio of
fresh fuel to recirculated gas in the mixture influences the temperature of the
reformer and that adjusting the temperature of the gas mixture allows the
reformer to operate in a desired temperature range. Id. citing Guenther ¶ 9.
The Examiner found Guenther discloses adjusting the fuel ratio in response
to load changes. Id. at 4–5 citing Guenther ¶¶ 9, 17.
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The Examiner found Guenther does not disclose measuring pressures
and temperatures as claimed. Id. at 4.
The Examiner found Mazumder discloses moving gaseous fuel
through a circuit in order to make electricity, including recirculating exhaust
gas and mixing it with freshly compressed air for reuse in the system. Id. at
5 citing Mazumder ¶ 2, Fig. 2. The Examiner found Mazumder discloses an
ejector 38, which is at the junction point between Mazumder’s exhaust or
recirculation line and air supply line. Id. citing Mazumder Figs. 2, 3. The
Examiner found Mazumder discloses a controller 82 to open or close a
control valve 80 to regulate flow rates of the first mixture, where the
controller uses feedback from temperature sensors 88, 92, 96, and pressure
sensors 86, 90, and 94 located around the ejector 38, which is a junction
point. Id. at 5–6 citing Mazumder ¶¶ 24, 25; Fig. 2. The Examiner stated
“[a] plain reading of Mazumder (figure 2) is that the pressure and
temperature sensors measure pressure and temperature where the sensors are
located and that the controller (82) determines an exhaust, or recirculation,
ratio, as a function of the measured parameters.” Id. at 6. The Examiner
concluded “in order to collect data with which to feed Guenther’s ratio-
adjustment algorithms, it would have been obvious to one of ordinary skill in
the art to measure three sets of temperature and pressure values around the
junction point as claimed.” Id.

Appellant’s contentions
Appellant contends Mazumder is concerned with high temperature
gases and flow for a gas turbine compressor, which is not anything like a
fuel stack, and Mazumder discloses structures and components related to
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Application 15/148,583

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temperatures and pressures to deal with anti-icing, which is not identified as
an issue in Guenther. Appeal Br. 6. Appellant argues neither Guenther nor
Mazumder discloses determining a recirculation ratio as a function of
parameters T1, T2, T3, p1, p2, and p3, and does not control the flow of the
recirculating line as a function of it. Id. Appellant argues the Examiner’s
rejection is based on hindsight because Guenther does not require any
temperature and pressure data to determine its ratio, and Mazumder does not
teach any data to determine a ratio based on all the parameters recited in
claim 1. Id. at 6–8.

Issue
Did Appellant demonstrate reversible error in the Examiner’s
determination that the method of claim 1 would have been obvious over
Guenther and Mazumder?

Discussion
At the outset, we are not persuaded by Appellant’s argument that
Mazumder is not structurally similar to the claimed invention. The
Examiner relies on Mazumder for the arrangement of pressure and
temperature sensors in order to provide information to regulate flow in fuel
apparatuses containing with recirculation systems. See Ans. 10. Indeed, it is
well established that “it is not necessary that the inventions of the references
be physically combinable to render obvious the invention under review.” In
re Sneed, 710 F.2d 1544, 1550 (Fed. Cir. 1983). In addition, “[c]ombining
the teachings of references does not involve an ability to combine their
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specific structures.” In re Nievelt, 482 F.2d 965, 968 (CCPA 1973).
Moreover, the Supreme Court in KSR stated
[a]s our precedents make clear, however, the analysis [under 35
U.S.C. § 103] need not seek out precise teachings directed to
the specific subject matter of the challenged claim, for a court
can take account of the inferences and creative steps that a
person of ordinary skill in the art would employ.
KSR Int’l. Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007).
That Mazumder discloses regulating flow for anti-icing purposes does
not demonstrate error in the Examiner’s position. As found by the
Examiner, Guenther discloses regulating the ratio of fuel to the recirculation
flow via the electronic control unit. Guenther ¶¶ 9, 17. However, Guenther
is silent as to the particular details of how to monitor and determine such
regulation. Thus, the Examiner’s reliance on Mazumder for further details
on how one of ordinary skill in the art would have provided information on
how to regulate the system of Guenther is reasonable. KSR Int’l. Co. v.
Teleflex Inc., 550 U.S. 398, 417 (2007) (“[w]hen a work is available in one
field of endeavor, design incentives and other market forces can prompt
variations of it, either in the same field or a different one. If a person of
ordinary skill can implement a predictable variation, § 103 likely bars its
patentability.”).
To the extent Appellant is arguing that because Mazumder relates to
anti-icing, Mazumder is non-analogous art, we agree with the Examiner that
Mazumder is reasonably pertinent to the problem with which the inventor is
concerned. Ans. 10–11. Mazumder, like Appellant, is concerned with
monitoring, and recirculating of a fuel-containing gas mixture moving
through a circuit. Spec. ¶¶ 7–10; Mazumder ¶¶ 24–30. Thus, Mazumder
would have commended itself to the inventor in considering parameters for
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regulating recirculation of fuels. In re ICON Health and Fitness, 496 F.3d
1374, 1379–80 (Fed Cir. 2007) (“‘A reference is reasonably pertinent if,
even though it may be in a different field from that of the inventor’s
endeavor, it is one which, because of the matter with which it deals,
logically would have commended itself to an inventor’s attention in
considering his problem.’” (quoting In re Clay, 966 F.2d 656, 659 (Fed. Cir.
1992)).
We are also not persuaded by Appellant’s argument that Mazumder
does not determine a recirculation ratio as recited in claim 1. Mazumder
discloses temperature sensors 88, 92, and 96, and pressure sensors 86, 90,
and 94 provide information to controller 82 to regulate control valve 80.
Mazumder ¶¶ 25, 26, 30; Fig. 2. Such temperature and pressure data
correspond to three sets of values around a junction point as found by the
Examiner. Although Appellant argues Mazumder does not disclose
determining a ratio from the pressure and temperature measurements, we
agree with the Examiner that these disclosures in Mazumder indicate that
Mazumder does determine a recirculation ratio. Ans. 12. In disclosing such
pressure and temperature values around the ejector or junction point are used
to regulate the control valve, Mazumder must necessarily determine the
relationship between such values in order for the controller to regulate the
control valve. As such, the Examiner’s rationale is not based on improper
hindsight as argued by Appellant.
In this regard, we observe that claim 1 does not recite any particular
ratio to be determined from each of the pressures and temperatures measured
in claim 1, only that a recirculation ratio be determined. Thus, we are not
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persuaded there is any patentable difference between the use of temperature
and pressures disclosed in Mazumder and the method recited in claim 1.
As to Appellant’s argument that Guenther discloses only that a
temperature of the reformer is influenced by the recirculation flow and does
not require temperature and pressure data to determine the ratio, we are also
not persuaded. Guenther discloses adjusting flow control valves via a
control unit. Guenther ¶ 17. Although Guenther discusses temperature
(Guenther ¶ 9), Guenther does not exclude the use of other measurements,
such as pressure, in order to provide suitable information regarding
recirculation flow.
As are result, we affirm the Examiner’s rejection of claim 1.

Rejections 2 and 3
Appellant does not separately argue claim 15, the subject of Rejection
2, and claims 16 and 17, the subject of Rejection 3, but relies on the
dependency thereof with respect to claim 1 as a basis for patentability. See
Appeal Br. 8. Thus, we affirm the Examiner’s rejections of claims 15–17
for the similar reasons as discussed above for claim 1.

DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 4–13 103 Guenther,
Mazumder
1, 4–14
15 103 Guenther,
Mazumder,
Clawson
15
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16, 17 103 Guenther,
Mazumder,
Clawson, Katano
16, 17
Overall
Outcome
1, 4–17
TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).

AFFIRMED