Ex Parte Ingman

Patent Trial and Appeal Board

Jan 31, 2013

11697156 (P.T.A.B. Jan. 31, 2013)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE PATENT TRIAL AND APPEAL BOARD
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Ex parte THOMAS M. INGMAN
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Appeal 2010-008497
Application 11/697,156
Technology Center 2800
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Before DENISE M. POTHIER, BARBARA A. BENOIT, and
TRENTON A. WARD, Administrative Patent Judges.

WARD, Administrative Patent Judge.

DECISION ON APPEAL
Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s final
rejection of claims 1-20. We have jurisdiction under 35 U.S.C. § 6(b). We
affirm.

STATEMENT OF THE CASE
Appellant’s claimed invention relates to a filter for reducing
electromagnetic interference generated by a power converter. See generally
Abstract. Claim 1 is illustrative with certain disputed limitations italicized:
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Application 11/697,156

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1. A filter for reducing electromagnetic interference
generated by a power converter, the filter comprising:
a first common-mode inductor comprising first and
second windings on a common core
the first winding connected between a first power
input line and a first input to the power converter
the second winding connected between a second
power input line and a second input to the power
converter
a first combination consisting of a first resistor and a first
voltage limiting device connected in series, the first
combination connected in parallel with the first winding to limit
a voltage across the common mode inductor in the event of a
common mode voltage surge.

THE REJECTIONS
The Examiner rejected claims 1-6 and 12-20 under 35 U.S.C. § 103(a)
as unpatentable over Shudarek (US 7,378,754 B2; issued May 27, 2008) and
Nordholm (US 3,536,998; issued Oct. 27, 1970). Ans. 4-8.1
The Examiner rejected claims 7-11 under 35 U.S.C. § 103(a) as
unpatentable over Shudarek, Nordholm, and Nijhof (US 3,538,417; issued
Nov. 3, 1970). Ans. 8-10.

CONTENTIONS
The Examiner finds that Shudarek discloses a filter for reducing
electromagnetic interference generated by a power converter, the filter
comprising a first common-mode inductor comprising a first winding and a
second winding on a common core; the first winding connected between a

1 Throughout this opinion, we refer to (1) the Appeal Brief (“App. Br.”) filed
Sept. 21, 2009, (2) the Examiner’s Answer (“Ans.”) mailed Mar. 4, 2010,
and (3) the Reply Brief (“Reply Br.”) filed Mar. 25, 2010.
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first power input line and a first input to the power converter the second
winding connected between a second power input line. Ans. 4. The
Examiner finds that Shudarek discloses every recited structural feature of
claim 1, except for “a first combination consisting of a first resistor and a
first voltage limiting device connected in series, the first combination
connected in parallel with the first winding.” Ans. 4. The Examiner cites
Nordholm as teaching this combination circuit in concluding that the claim
would have been obvious. Id.
Appellant argues that the “claimed subject matter addresses a different
problem and provides a different solution than that taught in the prior art.”
App. Br. 6 (emphasis omitted). Specifically, Appellant argues that
Nordholm teaches the use of a voltage limiting device to solve the problems
of potential damage to circuit components by absorbing the energy of a
voltage spike while the problem addressed by the claimed invention is to
prevent a common mode inductor from exacerbating an externally applied
common mode voltage surge. Id.

ISSUE
Under § 103, has the Examiner erred in rejecting claim 1 by finding
that the combination of the cited prior art teaches a “first combination
connected in parallel with the first winding to limit a voltage across the
common mode inductor in the event of a common mode voltage surge”?

ANALYSIS
On this record, we find no error in the Examiner’s obviousness
rejection of claim 1. The Examiner found that Shudarek discloses every
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recited structural feature of claim 1 except for the combination of a resistor
and a voltage limiting device connected in series, and the combination
connected in parallel with a winding. Ans. 4. The Examiner cites
Nordholm, in combination with Shudarek, as disclosing this combination
circuit. Id. Appellant does not dispute that the circuit of Nordholm is the
same combination circuit as the claimed invention. Reply Br. 4 (“The
Applicant agrees that the circuit configuration (a series combination of a
resistor and a voltage limiting device connected in parallel with a winding)
taught by Nordholm is the same as the circuit recited in the claimed
invention.” (emphasis omitted)).
Citing to MPEP § 2141.02(III), Appellant argues that although the
combination circuit in the cited prior art is the same, Appellant’s claimed
invention addresses a different problem than the problem addressed by the
prior art. App. Br. 4; Reply Br. 4. Specifically, Appellant states that
Nordholm teaches the use of a voltage limiting device to solve the problems
of potential damage to circuit components by absorbing the energy of a
voltage spike. App. Br. 6. Appellant argues that the problem addressed by
the claimed invention is not to absorb the energy of a voltage surge
emanating from an inductive component but to prevent the common mode
inductor from exacerbating an externally applied common mode voltage
surge. Id.
As conceded by Appellants, Nordholm discloses the combination
circuit and limits the voltage across the common mode inductor in the event
of a voltage surge. Reply Br. 4; see also Ans. 4 (citing Nordholm, col. 5, ll.
65-68). Apparatus claims, such as claim 1, must be structurally
distinguishable from prior art to be patentable. Because Appellants’ claim 1
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is not structurally distinguishable over the cited prior art, we agree with
Examiner’s finding that claim 1 is not patentable. Additionally, we are not
persuaded of error in the Examiner’s rejection of method claim 20 because
the recited step of limiting a voltage across the common mode inductor in
the event of a common mode voltage surge is taught by Nordholm. See Ans.
4 (citing Nordholm, col. 5, ll. 65-68), 13; Reply Br. 4.
Appellant additionally argues that the claimed subject matter is
patentable because it provides an innovative solution to a problem “not
recognized in the prior art,” namely a recognition that that the inductor
actually adds to the voltage surge in a power spike. App. Br. 4-5 (citing
MPEP § 2141.02; In re Wiseman, 596 F.2d 1019, 1022 (CCPA 1979))
(emphasis omitted). The Court in Wiseman affirmed a rejection against
claims directed to grooved disc brakes because although applicants
discovered a new problem, the claimed solution of placing grooves in the
disc would have been obvious from the prior art which placed grooves in
disc brakes for a similar problem. 596 F.2d at 1022. Thus, Appellant’s
arguments are unavailing because we find likewise that the claimed
combination circuit would have been obvious based on Nordholm’s teaching
which includes such a combination circuit to address a similar problem. To
the extent that Appellant is attempting to argue that Nordholm is
nonanalogous prior art, we disagree, as Nordholm is in the same field of
endeavor as Appellant and is reasonably pertinent to the problem with which
Appellant was concerned as previously discussed.
We are therefore not persuaded that the Examiner erred in rejecting
independent claim 1, and claims 2-20 not separately argued with
particularity.
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ORDER
The Examiner’s decision rejecting claims 1-20 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)(1)(iv).

AFFIRMED

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