Ex Parte Ackermann et al

Patent Trial and Appeal Board

Aug 3, 2017

13390867 (P.T.A.B. Aug. 3, 2017)

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.
13/390,867 02/16/2012 Markus Ackermann ACKERMANN 1030
20151 7590 08/07/2017
HENRY M FEIEREISEN, LLC
HENRY M FEIEREISEN
708 THIRD AVENUE
SUITE 1501
NEW YORK, NY 10017
EXAMINER
FANTU, YALKEW
ART UNIT PAPER NUMBER
2859
NOTIFICATION DATE DELIVERY MODE
08/07/2017 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):
INFO @ FEIEREISENLLC.COM
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MARKUS ACKERMANN, GERALD AMLER, and
ANDREAS NAGEL
Appeal 2015-008118
Application 13/390,8671
Technology Center 2800
Before THU A. DANG, KRISTEN L. DROESCH, and J. JOHN LEE,
Administrative Patent Judges.
DROESCH, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants seek review under 35 U.S.C. § 134(a) from the Examiner’s
final rejection of claims 3 and 4,2 all of the pending claims. We have
jurisdiction under 35 U.S.C. § 6(b).
We REVERSE and enter a new ground of rejection pursuant to our
authority under 37 C.F.R. § 41.50(b).
1 Appellants identify the real party-in-interest as Siemens Aktiengesellschaft.
See App. Br. 2.
2 Claims 1 and 2 have been cancelled.
Appeal 2015-008118
Application 13/390,867
BACKGROUND
The disclosed invention relates to a method for discharging an
intermediate circuit capacitor of an intermediate voltage circuit converter
with an electronic power converter. See Spec. 1 8, Abstract.
Figure 1 of the Application is reproduced below:
Figure 1 depicts intermediate voltage circuit converter 2 able to be
connected to a single-phase AC supply network (not shown) by way of pre­
charging circuit 6, bridging circuit 8, transformer T, and main switch HS.
See Spec. 114. Primary winding 20 of transformer T is able to be connected
by main switch HS to an AC supply network (not shown). See id. Power
converter 4 has two bridging branches 10, 12, which each feature
electrically-switchable power semiconductors Al, A2, and A3, A4
connected in series. See id. A first connection of secondary winding 16 of
transformer T is connected by bridging circuit 8 to AC voltage-side
connection 14 of bridging branch 10 of power converter 4. See id. Bridging
circuit 8 includes line contactor NS. See id. A second connection of
secondary winding 16 is connected directly to AC voltage-side connection
2
Appeal 2015-008118
Application 13/390,867
18 of bridging branch 12. See id. Connected electrically in parallel to
bridging circuit 8 is pre-charging circuit 6 that includes pre-charging
contactor VS and pre-charging resistor Rv connected electrically in series.
See id.
Intermediate voltage circuit converter 2 is connected to a single-phase
AC supply network (not shown) when main switch HS and pre-charging
contactor VS are closed, thereby connecting a current path by which a
charge current flows to charge intermediate circuit capacitor Czk. See id.
115. When, for example, 80% of the maximum charge state is reached for
intermediate circuit capacitor Czk, line contactor NS is closed, which bridges
the pre-charging circuit 6. Pre-charging contactor VS can subsequently be
opened. See id.
Intermediate circuit capacitor Czk is discharged when main switch HS
is opened, followed by opening of line contactor NS and closing of pre­
charging contactor VS. See id. H 16—17. Pre-charging resistor Rv is
connected together with secondary winding 16 of transformer T in parallel
with AC voltage side connections 14, 18 of power converter 4. In order for
pre-charging resistor Rv to be connected electrically in parallel to
intermediate circuit capacitor Czk, only two of the four switchable power
semiconductors of power converter 4 are switched on, either A1 and A4 or
A2 and A3.
CLAIMED SUBJECT MATTER
Representative claim 3, reproduced from the Claims Appendix of the
Appeal Brief, reads as follows (disputed limitations in italics)'.
A method for discharging an intermediate circuit capacitor of
an intermediate voltage circuit converter with an AC voltage-
side electronic power converter having a plurality of switchable
power semiconductors, the method comprising the steps of:
3
Appeal 2015-008118
Application 13/390,867
opening a main switch arranged between an AC power
supply network and a primary winding of a transformer,
opening a line contactor connected between a first terminal of a
secondary winding of the transformer and a first AC voltage-
side connection in a first branch of the electronic power
converter, with a second terminal of the secondary winding of
the transformer being connected to a second AC voltage-side
connection in a second branch of the electronic power
converter,
closing a pre-charging contactor, which is connected in
series with a pre-charging resistor, with the series connection of
the pre-charging contactor and the pre-charging resistor being
connected in parallel with the line contactor, and
switching on two switchable power semiconductors of the
plurality of switchable power semiconductors, which are
located diagonally opposite each other in different branches of
the electronic power converter, thereby discharging the
intermediate circuit capacitor via a current path formed by the
pre-charging contactor, the secondary winding of the
transformer and the two switchable power semiconductors.
REJECTION ON APPEAL AND APPLIED PRIOR ART
Claims 3 and 4 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Nagel et al. (US 7,009,853 B2, issued March 7, 2006)
(“Nagel”) and Pond (US 5,943,222, issued Aug. 24, 1999).
ANALYSIS
We have reviewed the Examiner’s rejection in light of Appellants’
arguments in the Appeal Brief, the Examiner’s Answer, and Appellants’
arguments in the Reply Brief. We are persuaded the Examiner erred. We
highlight and address specific findings and arguments below for emphasis.
The Examiner finds that Nagel teaches all of the limitations of claim 1
except for “a pre-charging contactor, which is connected in series with a pre­
charging resistor.” See Final Act. 3^4 (citing Nagel, 3, 21—45, 6:5—18, Fig.
4
Appeal 2015-008118
Application 13/390,867
3: switches Ql, Q2 ... Qn; Cl, C2 .. .Cn connected to secondary winding of
Tl, T2...Tn).
Figure 3 of Nagel is reproduced below:
Figure 3 depicts AC source WQ, supplied with power from DC source
GQ, and including switch Q, diode D, inductor coil L, pulse width
modulator regulating system for driving switch Q, and downstream H bridge
having switches Qa.. .Qd for generating from the direct current the
alternating current ipri required to be supplied to primary windings of
transformers Tl to TN. See Nagel, 3:22—29, 4:59—5:13. Figure 3 further
depicts rectifiers G1 to GN in the form of a bridge circuit connected to each
of the secondary windings of transformers Tl to TN. See id. at 3:33—34,
5:14—17. Connected downstream from rectifiers G1 to GN are voltage
regulators R1 to RN to drive semiconductor switches Ql to QN, used with
diodes D1 to DN to connect to respective output capacitors Cl to CN. See
id. at 3:33—43, 5:14—24.
The Examiner relies on Pond for teaching closing a pre-charging
contactor that is connected in series with a pre-charging resistor, with the
series connection of the pre-charging contactor and pre-charging resistor
5
Appeal 2015-008118
Application 13/390,867
being connected in parallel with the line contactor. See Final Act. 4 (citing
Pond, Fig. 11: precharge circuit 416, 11:26-40).
Figure 11 of Pond is reproduced below:
400
/
Figure 11 depicts three-phase AC motor drive system 400 including
rectifier circuit 406, switching circuit 408, dynamic brake circuit 414, and
precharge circuit 416. Pond, 11:26—34.
The Examiner concluded that it would have been obvious for one with
ordinary skill in the art at the time of the invention to incorporate a pre­
charge circuit to the switched power supply apparatus of Nagel in view of
Pond’s teachings that “the precharge circuit preliminary mode which is used
to limit the incoming currents from the power source such that a controlled
rise time of the system voltage during power up is achieved, which is useful
in high voltage environment.” Final Act. 4—5.
Appellants first argue that none of the figures of Nagel show
switchable power semiconductors, which are located diagonally opposite
each other in different branches of the electronic power converter. See App.
Br. 5, 7. Appellants further argue that assuming output capacitor Cl to CN
6
Appeal 2015-008118
Application 13/390,867
of Nagel could be considered the intermediate circuit capacitor, Nagel’s
circuitry only charges a capacitor, but does not allow discharging a capacitor
via a current path formed by a pre-charging contactor as well as via the
secondary winding of transformer T1 to TN and two switchable power
semiconductors (i.e., components of H bridge circuits G1 to GN). See id. at
7. Appellants contend capacitors Cl to CN can never be discharged via the
secondary winding of transformers T1 to TN because: (1) diodes D1 to DN
of Fig 3 of Nagel block current flow toward the secondary winding of
transformers T1 to TN, and (2) the polarity of the diodes in bridge circuits
G1 to GN also prevent current flow of a voltage having the polarity of
output capacitors Cl to CN through diodes D1 to DN (which are reverse-
biased) and the second windings of transformers T1 to TN. See id. at 7—8.
The Examiner responds,
[T]he AC-source WQ, as a step down converter (Col. 5, lines 1-
10) supplies current through transformer Tn and rectified by
bridge circuit Gl-GN with voltage regulator R1 to RN that
drive the switches 01 to QN charges the intermediate capacitor
CN. When the source WQ switches off by the control main
switches, the fully charged capacitors Cl to CN discharge as
outputs (Fig. 3, Vout.l to Vout. n) to the load. Any circuit
arrangements with capacitor for discharge that includes an input
voltage source, a rectifier bridge connected to the input voltage
source, and at least two capacitor charge switches linked to a
direct current side of the rectifier bridge are common circuit
arrangements for controlled charge and discharge capacitors,
and the Nagel circuit arrangement has this common circuit
arrangements known to one skilled in the art.
Ans. 7—8 (emphasis added).
In response, Appellants point out that the Examiner’s additional
findings do not address the disputed language of claim 3. See Reply
Br. 3. Specifically, Appellants argue that “[according to the
7
Appeal 2015-008118
Application 13/390,867
Examiner’s interpretation, a DC voltage from the intermediate circuit
capacitor would not be transmitted via a transformer in Nagel’s circuit
in Figure [3].” Id. at 3^4. Appellants point out that “the current path
for discharging the intermediate circuit capacitor is unambiguously
recited in claim 3, with the discharge current flowing through the
pre-charging contactor, the secondary winding of the transformer and
the two switchable power semiconductors, and not through any
connected load.” Id. at 4.
We agree with Appellants with respect to this point. The Examiner
does not provide sufficient factual basis to demonstrate that Nagel alone, or
in combination with Pond, teaches or suggests discharging an intermediate
circuit capacitor via a current path formed by the secondary winding of the
transformer and two switchable power semiconductors, as required by claim
3. Therefore, based on the record before us, we are persuaded of at least one
error in the Examiner’s reliance on the combined teachings and suggestions
of the cited prior art combination to teach or suggest the disputed limitation
of claim 3, such that we are persuaded the Examiner erred in rejecting claim
3.
NEW GROUND OF REJECTION
Claim 4 recites, “[t]he method of claim 1, further comprising . . . .”
Claim 1, however, has been cancelled. Because claim 4 is dependent upon a
cancelled claim, we cannot ascertain the metes and bounds of claim 4.
Accordingly, we enter a new ground of rejection of claim 4 under 35 U.S.C.
§112, second paragraph, as indefinite for failing to particularly point out
and distinctly claim the subject matter which the applicant regards as his
invention.
8
Appeal 2015-008118
Application 13/390,867
As a matter of procedure, we reverse the prior art rejection of claim 4,
When the analysis of a claim indicates the need for “speculations and
assumptions,” a rejection of the claims based on prior art is likely
In re Steele, 305 F.2d 859, 862-63 (CCPA 1962). Therefore, the
indefiniteness of claim 4 prevents us from reaching the issue of obviousness.
DECISION
We REVERSE the rejection of claim 3.
We REVERSE the rejection of claim 4 pro forma.
We enter a NE W GROUND OF REJECTION of claim 4 under 35
U.S.C. § 112, second paragraph, for failing to particularly point out and
distinctly claim the invention.
This decision contains a new ground of rejection pursuant to 37
C.F.R. § 41.50(b). Section 41.50(b) provides “[a] new ground of rejection
pursuant to this paragraph shall not be considered final for judicial review.”
Section 41.50(b) also provides:
When the Board enters such a non-final decision, the appellant,
within two months from the date of the decision, must exercise
one of the following two options with respect to the new ground
of rejection to avoid termination of the appeal as to the rejected
claims:
(1) Reopen prosecution. Submit an appropriate amendment of
the claims so rejected or new Evidence relating to the claims so
rejected, or both, and have the matter reconsidered by the
examiner, in which event the prosecution will be remanded to the
examiner. The new ground of rejection is binding upon the
examiner unless an amendment or new Evidence not previously
of Record is made which, in the opinion of the examiner,
overcomes the new ground of rejection designated in the
decision. Should the examiner reject the claims, appellant may
again appeal to the Board pursuant to this subpart.
9
Appeal 2015-008118
Application 13/390,867
(2) Request rehearing. Request that the proceeding be reheard
under § 41.52 by the Board upon the same Record. The request
for rehearing must address any new ground of rejection and state
with particularity the points believed to have been
misapprehended or overlooked in entering the new ground of
rejection and also state all other grounds upon which rehearing
is sought.
REVERSED; 37 C.F.R, $ 41.50(b)
10