Ex Parte Cheng

Board of Patent Appeals and Interferences

Oct 13, 2010

10842018 (B.P.A.I. Oct. 13, 2010)

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.
10/842,018 05/07/2004 Chung Yan Cheng 3165A-000219 2330
27572 7590 10/13/2010
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS, MI 48303
EXAMINER
STERRETT, JEFFREY L
ART UNIT PAPER NUMBER
2838
MAIL DATE DELIVERY MODE
10/13/2010 PAPER
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.
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte CHUNG YAN CHENG
____________

Appeal 2009-007137
Application 10/842,018
Technology Center 2800
____________

Before ROBERT E. NAPPI, CARLA M. KRIVAK, and
CARL W. WHITEHEAD, JR., Administrative Patent Judges.

NAPPI, Administrative Patent Judge.

DECISION ON APPEAL1

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, or for filing a request for rehearing,
as recited in 37 C.F.R. § 41.52, begins to run from the “MAIL DATE”
(paper delivery mode) or the “NOTIFICATION DATE” (electronic delivery
mode) shown on the PTOL-90A cover letter attached to this decision.
Appeal 2009-007137
Application 10/842,018

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STATEMENT OF THE CASE
Appellant appeals under 35 U.S.C. § 134 from the rejection of claims
1-22.2 (App. Br. 9-10.) We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
The Disclosed Invention3
The disclosed invention includes a power converter having a rectifier
and a circuit for controlling the reverse recovery current through the
rectifiers. (Spec. ¶ [0021]; FIG. 2.) Particularly, the power converter
includes a switching circuit 12 having switches (Q1, Q2, Q3, and Q4), a
positive rail 18, and a negative rail 20; an isolation circuit 14; and an output
circuit 16 having rectifiers (40a and 40b), a primary inductor 42,
supplemental winding 56, and a diode 54. (Spec. ¶¶ [0016-0019]; FIG. 2.)
The power converter operates to reduce the reverse recovery current
through the rectifiers:
when switches Q1-Q4 of bridge-type switching circuit 12 are
turned off, supplemental winding 56 applies a reverse bias to
output rectifiers 40a, 40b to prevent output rectifiers 40a, 40b
from conducting. During this interval, induced voltage at
supplemental winding 56 directs at least a substantial portion of
the freewheeling current through diode 54. This insures that
minimal or, in some cases, no current flows through output
rectifiers 40a, 40b prior to one of the respective switching pairs
Q1, Q2 or Q3, Q4 turning on. Thus no reverse recovery current
flows through output rectifiers 40a, 40b when one of the
respective switching pairs Q1, Q2 or Q3, Q4 turn on.
(Spec. ¶ [0021].)

2 Appellant’s Appeal Brief (filed August 21, 2008) (“App. Br.”) and Reply
Brief (filed December 30, 2008) (“Reply Br.”) and the Examiner’s Answer
(mailed November 21, 2008) (“Ans.”) are referenced here.
3 The ensuing description constitutes findings of fact.
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Exemplary claim 1 follows:
1. A power converter circuit comprising:
a primary inductor having a first end directly connected
to a first output of the power converter circuit; and
a reverse recovery suppression circuit comprising:
a secondary inductor having a first end connected
directly to a second end of the primary inductor; and
a diode having a first end connected directly to a
second end of the secondary inductor and a second end
connected directly to a second output of the power converter
circuit, wherein the secondary inductor provides the sole
inductance of the reverse recovery suppression circuit and
causes freewheeling current to flow through the diode.

The Examiner relies on the following prior art references:
Smith US 4,977,493 Dec. 11, 1990
Mantov US 6,377,481 B1 Apr. 23, 2002
Claims 1, 2, 4-7, 12-14, and 16-18 stand rejected under 35 U.S.C.
102(b) as anticipated by Mantov.
Claims 3, 8, 15, 19, and 20 stand rejected as obvious under 35 U.S.C.
103(a) based on Mantov.
Claims 9-11, 21, and 22 stand rejected as obvious under 35 U.S.C.
103(a) based on Mantov and Smith.

ISSUES
Appellant’s responses to the Examiner’s positions present the
following issues:
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1. Did the Examiner err in finding that Mantov discloses a power
converter circuit having the arrangement of elements recited in claim 1, and
as similarly recited in claims 12 and 16?
2. Did the Examiner err in finding that Mantov renders obvious claim
20?

FINDINGS OF FACT (FF)
Mantov
1. Mantov discloses a power supply circuit comprising a diode and a
circuit to suppress reverse current flow (i.e., the diode reverse recovery
circuit) through the diode. (Col. 1, ll. 12-31; col. 3, ll. 1-23.)
2. The power supply circuit comprises diodes (416 and 417), a
primary inductor (12), a first output at the upper terminal of a capacitor (20),
a second output at the lower terminal of the capacitor (20), and a reverse
recovery suppression circuit (24) having a secondary inductor (26 and
auxiliary inductor 28), and a diode (DA). (FIG. 6.) The primary inductor
(12) has a first end (denoted by a dot) and a second end (i.e., the other end).
(FIG. 6.) The first end of the primary inductor (12) is directly connected to
the upper terminal of the capacitor (20). (FIG. 6.) The secondary inductor
has a first end (denoted by a dot on inductor 26) and a second end (i.e., the
lower end of inductor 28). (FIG. 6.) The first end of the secondary inductor
(26 and 28) is directly connected to the second end of the primary inductor
(12). (FIG. 6.) The diode (DA) has a first end (i.e., the cathode) and a
second end (i.e., the anode). (FIG. 6.) The first end of the diode DA is
directly connected to the second end of the secondary inductor (26 and 28).
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(FIG. 6.) The second end of the diode DA is connected to the second output
of the power supply circuit. (FIG. 6.)
3. Mantov discloses another power supply circuit with an additional
set of windings (728). (Col. 6, ll. 18-21; FIG. 9.) “In this example, . . . the
leakage inductance of the set of additional windings 726 is sufficiently high
to enable elimination of the auxiliary inductor while retaining the
functionality of that omitted element.” (Col. 6, ll. 21-25.) “The example of
FIG; 9 [sic] can be applied to any of the circuits described above (e.g., FIGS.
1-8) to eliminate the auxiliary inductor 28 without departing from the scope
or spirit of the invention.” (Col. 6, ll. 27-30.)

PRINCIPLES OF LAW
The Examiner bears an initial burden of factually supporting an
articulated rejection. In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992).
“It is axiomatic that anticipation of a claim under § 102 can be found only if
the prior art reference discloses every element of the claim . . . .” In re King,
801 F.2d 1324, 1326 (Fed. Cir. 1986). Under § 103, “‘there must be some
articulated reasoning with some rational underpinning to support the legal
conclusion of obviousness.’” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398,
418 (2007) (citation omitted). On appeal, Appellant may rebut the
Examiner’s findings and reasoning with opposing evidence or argument.
Failure to do so may constitute a waiver of potential arguments. See 37
C.F.R. § 41.37(c)(1)(vii); Hyatt v. Dudas, 551 F.3d 1307, 1313-14 (Fed. Cir.
2008) (The Board may treat arguments Appellant failed to make for a given
ground of rejection as waived.); Ex parte Frye, 94 USPQ2d 1072, 1075
(BPAI 2010) (precedential) (“If an appellant fails to present arguments on a
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particular issue — or, more broadly, on a particular rejection — the Board
will not, as a general matter, unilaterally review those uncontested aspects of
the rejection.”).

ANALYSIS
Claims 1-19
35 U.S.C. 102(b) rejection of claims 1, 2, 4-7, 12-14, and 16-18
Appellant asserts that the “circuit elements of Mantov are not
arranged as required by the claims,” that the “Examiner has not pointed to
one,[sic] consistent teaching in Mantov that shows the elements arranged as
provided for by the claims,” and that the Examiner has cobbled together
various elements from different, alternative illustrations. (App. Br. 10;
Reply Br. 2-4.) As found by the Examiner, however, Mantov does disclose
the circuit elements arranged as recited in claim 1. (Ans. 7-9; accord FF 1 -
3.) Further, we do not consider the teachings of the reference to be cobbled
together; rather, the Examiner instead referenced the circuit of Figure 6 and
applied the teaching of the single inductor (726) of Figure 9 to the circuit of
Figure 6. (Ans. 5-7; accord FF 2-3.)
Appellant also asserts that the claims require a reverse recovery circuit
having only one inductance and that the “reverse recovery circuits of
Mantov require two inductances.” (App. Br. 10-11.) Appellant argues that
“Figure 9 of Mantov necessarily requires two inductances, a primary
inductance and a leakage inductance,” but claim 1 recites that the
“secondary inductor provides the sole inductance of the reverse recovery
suppression circuit” (App. Br. 11). We concur with the Examiner’s finding
that Mantov’s single inductor (i.e., 728 of Figure 9) provides the sole
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inductance of the reverse recovery suppression circuit and can replace the
two inductances (26 and 28) of Figure 6. (Ans. 17-18; accord FF 3.) As
also found by the Examiner, although the inductance provided by the single
inductor (728) may include multiple virtual inductances, “the overall
inductance of the reverse recovery suppression circuit is provided by
only . . . the single inductor.” (Ans. 18; accord FF 3.)
Appellant argues for the first time in the Reply Brief that the circuit
elements of Figure 9 of Mantov are not arranged in the manner recited in
claim 1. (Reply Br. 3-4.) In particular, Appellant argues that “[u]pon
review of Figure 9 of Mantov . . . it is clear that the ‘first end’ of inductor 12
. . . is not directly connected to any output.” (Reply Br. 3 (emphasis
omitted).) Appellant also argues that the second end of the primary inductor
and the first end of the primary inductor of Figure 9 of Mantov “are not
connected at all, let alone ‘directly connected’ as required by the
claims . . . .” (Reply Br. 4.)
Because these arguments appear for the first time in the Reply Brief
and do not address a point raised for the first time in the Examiner's Answer,
(i.e., Appellant has not shown that they were necessitated by the Answer),
they are untimely and deemed waived. See Ex parte Nakashima, 93
USPQ2d 1834 (BPAI 2010); Ex parte Borden, 93 USPQ2d 1473 (BPAI
2010) (informative).
Therefore, we will sustain the Examiner’s 35 U.S.C. 102(b) rejection
of claim 1, and claims 2, 4-7, 12-14, and 16-18 which are grouped with
claim 1.

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35 U.S.C. 103(a) rejection of claim 3.
We will also sustain the Examiner’s 35 U.S.C. 103(a) rejection of
claim 3 as Appellant’s arguments with respect to this rejection rely upon the
arguments presented with respect to claim 1, which, as discussed supra, are
not persuasive. (App. Br. 11.)
35 U.S.C. 103(a) rejection of claims 8, 15, and 19. 4
With respect to claims 8, 15, and 19, Appellant argues that these
claims are patentable over Mantov for the reasons discussed with respect to
claim 1. (App. Br. 12.) Thus, we sustain the Examiner’s 35 U.S.C. 103(a)
rejection of claims 8, 15, and 19.
35 U.S.C. 103(a) rejection of claims 9-11.
We will also sustain the Examiner’s 35 U.S.C. 103(a) rejection of
claims 9-11 as Appellant’s arguments with respect to this rejection rely upon
the arguments presented with respect to claim 1, which, as discussed supra,
are not persuasive. (App. Br. 13.)

Claims 20-22
35 U.S.C. 103(a) rejection of claim 20.
Appellant argues that “[a]s with claims 1, 12, and 16, Appellant
submits that claim 20 describes a power converter circuit that is arranged
and operates differently from Markov [sic].” (App. Br. 12.) In particular,

4 We note that by the column heading on page 12 of the Appeal Brief, it
appears that Appellant has grouped claims 8, 15, and 19 with claim 20.
However, the narrative presents separate arguments with respect to claim 20
and merely states that claims 8, 15, and 19 distinguish over Mantov for the
same reasons as claim 1. Accordingly, we separately address the
Examiner’s 35 U.S.C. 103(a) rejection of claim 20, and dependent claims 21
and 22, based upon Mantov.
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Appellant argues that Mantov does not disclose a second inductor that
reverse biases the first and second diodes in a rectifier. (App. Br. 12.)
However, Mantov does disclose a rectifier having first and second diodes
(i.e., 416 and 417). (Ans. 15-16; accord FF 2-3.) Mantov discloses a
second inductor (i.e., 26 and 28) that reverse biases diodes 416 and 417.
(Ans. 15-16; accord FF 2-3.) Further, Appellant’s statements, on page 12 of
the Appeal Brief, regarding what a rectifier includes, appear to be the same
arrangement of Mantov’s inductors 26 and 28 that are arranged to reverse
bias the main diode 16. We note that, as depicted in the circuit of Figure 6,
the main diode (item 16 of Figure 5) “actually comprises two diodes 416,
417 comprising a half-bridge rectifier . . . .” (Mantov, col. 5, ll. 43-46.)
Moreover, according to Appellant’s patent application, the supplemental
winding 56 of Figure 2 “applies a reverse bias to output rectifiers 40a, 40b to
prevent output rectifiers 40a, 40b from conducting.” (Spec. ¶ [0021].)
Thus, if the supplemental winding reverse biases diodes 40a and 40b as
alleged by Appellant, the secondary inductor of Mantov must also reverse
bias diodes 416 and 417 because the diodes 416 and 417 and the secondary
inductor of Mantov are arranged in the same manner as the diodes 40a and
40b and the supplemental winding in Appellant’s invention. (See FF 2.)
Therefore, we will sustain the Examiner’s rejection of claim 20 and
dependent claims 21 and 22 as Appellant did not present separate
patentability arguments for these dependent claims. (See App. Br. 13.)

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CONCLUSIONS
The Examiner did not err in finding that Mantov discloses a power
converter circuit having the arrangement of elements recited in claim 1. The
Examiner did not err in finding that Mantov renders obvious claim 20.

DECISION
We affirm the Examiner’s decision rejecting claims 1-22.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136. See 37 C.F.R.
§ 1.136(a)(1)(v) (2010).

AFFIRMED

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HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS, MI 48303