Ex Parte Vogman

Board of Patent Appeals and Interferences

Jun 26, 2003

09289420 (B.P.A.I. Jun. 26, 2003)

The opinion in support of the decision being entered today was not written for
publication and is not binding precedent of the Board.
Paper No. 17
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte VIKTOR D. VOGMAN
____________
Appeal No. 2001-1627
Application No. 09/289,420
____________
ON BRIEF
____________
Before FLEMING, DIXON, and LEVY, Administrative Patent Judges.
LEVY, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from the
examiner's final rejection of claims 1-31, which are all of the
claims pending in this application.

Appeal No. 2001-1627
Application No. 09/289,420
Page 2
BACKGROUND
Appellant's invention relates to a DC-DC voltage converter.
An understanding of the invention can be derived from a reading
of exemplary claim 1, which is reproduced as follows:
1. A DC-to-DC converter having an input voltage and an
output voltage, comprising:
a circuit topology such that, in operation, the input and
output voltages have the same polarity, and that a magnitude of a
ratio of the input voltage to the output voltage of said DC-to-DC
converter is capable of being equal to, greater than, or less
than one;
said circuit topology being further such that at least one
capacitor and alternative coils of a two-coil inductor are
employed in a primary and a secondary circuit loop of said
DC-to-DC converter;
said primary and secondary circuit loops not being
electrically isolated.
The prior art references of record relied upon by the
examiner in rejecting the appealed claims are:
Cuk et al. (Cuk) 4,274,133 June 16, 1981
Bang 5,621,625 Apr. 15, 1997
Yasumura 5,835,368 Nov. 10, 1998
Claims 1-31 stand rejected under 35 U.S.C. § 102(e) as being
clearly anticipated by Yasumura.
Claims 1-25 stand rejected under 35 U.S.C. § 102(b) as being
clearly anticipated by Cuk.
Appeal No. 2001-1627
Application No. 09/289,420
Page 3
Claims 1-31 stand rejected under 35 U.S.C. § 102(b) as being
clearly anticipated by Bang.
Rather than reiterate the conflicting viewpoints advanced by
the examiner and appellant regarding the above-noted rejections,
we make reference to the examiner's answer (Paper No. 13, mailed
November 21, 2000) and the final rejection (Paper No. 7, mailed
March 28, 2000) for the examiner's complete reasoning in support
of the rejections, and to appellant's brief (Paper No. 12, filed
December 4, 2000) and reply brief (Paper No. 14, filed January
24, 2001) for appellant's arguments thereagainst. Only those
arguments actually made by appellant have been considered in this
decision. Arguments which appellant could have made but chose
not to make in the brief have not been considered. See 37 CFR
1.192(a).
OPINION
In reaching our decision in this appeal, we have carefully
considered the subject matter on appeal, the rejections advanced
by the examiner, and the evidence of anticipation relied upon by
the examiner as support for the rejections. We have, likewise,
reviewed and taken into consideration, in reaching our decision,
appellant's arguments set forth in the briefs along with the
Appeal No. 2001-1627
Application No. 09/289,420
Page 4
examiner's rationale in support of the rejections and arguments
in rebuttal set forth in the examiner's answer.
Upon consideration of the record before us, we affirm-in-
part.
We begin with the rejection of claims 1-25 under 35 U.S.C.
§ 102(e) as being clearly anticipated by Cuk. The examiner's
rejection, in its entirety (final rejection, page 3) is that "Cuk
et al. disclose DC to DC converter having reduced ripple without
need for adjustment in figures 1-5." To anticipate a claim, a
prior art reference must disclose every limitation of the claimed
invention, either explicitly or inherently. In re Schreiber, 128
F.3d 1473, 1477, 44 USPQ2d 1429, 1431 (Fed. Cir. 1997). As
stated in In re Oelrich, 666 F.2d 578, 581, 212 USPQ 323, 326
(CCPA 1981) (quoting Hansgirg v. Kemmer, 102 F.2d 212, 214, 40
USPQ 665, 667 (CCPA 1939)) (internal citations omitted):
Inherency, however, may not be established by probabilities
or possibilities. The mere fact that a certain thing may
result from a given set of circumstances is not sufficient.
Appellant asserts (brief, page 14) that claims 1-25 are not
met by Cuk for the reasons set forth in the brief with respect to
Yasumura, and adds that Cuk does not expressly or inherently meet
limitations directed to non-electrically isolated primary and
secondary circuit loops; nor to an input and output voltage
Appeal No. 2001-1627
Application No. 09/289,420
Page 5
1 McGraw-Hill Electronics Dictionary, Fifth Edition, 1994.
2 The Illustrated Dictionary of Electronics, 4th Edition, 1988.
having the same polarity. It is argued (brief, page 8) that the
claim 1 limitation directed to the use of an inductor in contrast
to a magnetically coupled transformer is not met. The issue is
whether a transformer meets the claimed two-coil inductor. The
examiner's position (final rejection, page 4) is that appellants
primary and secondary windings form a transformer, and that since
the references each include a transformer, the claimed "two-coil
inductor" is met. The examiner (answer, page 4) relies upon a
dictionary1 definition of a transformer to support his position.
Appellant responds (reply brief, pages 3 and 4) by citing a
different dictionary2 definition of a transformer to support
appellants position that a transformer requires a ferromagnetic
core, whereas an inductor may or may not have a ferromagnetic
core. Appellant asserts (id.) that because an inductor do not
necessarily have a ferromagnetic core, that the transformers of
the prior art are not equivalent to the claimed two-coil
inductor.
We find that appellant's specification (page 4) discloses
inductor 160 to have a core. However, the specification is not
specific as to whether the core is a ferromagnetic core or an air
Appeal No. 2001-1627
Application No. 09/289,420
Page 6
core. In any event, the specification (page 5) discloses that
the embodiment of the invention does not employ a transformer,
and that (page 6) a less expensive component such as inductor 160
may be used instead of a transformer. However, we need not
decide the issue of whether inductor 160 is in fact a transformer
because claim 1 neither claims nor precludes a transformer. The
claim requires a two-coiled conductor. Cuk discloses a
transformer T which includes two coiled inductors L1 and L2. From
the use of the transitional phrase "comprising", we consider the
claim to be open-ended, and find no language in claim 1 which
would preclude a transformer. Accordingly, because the
transformer of Cuk includes two inductor coils, we find that Cuk
meets the claimed two-coiled inductor.
Appellant further asserts (brief, page ) that the recitation
of a ratio of the input voltage to the output voltage is capable
of being equal to, greater than, or less than one, is not met.
The examiner's position (answer, page 5) is that the claim
language does not constitute a limitation in a patentable sense,
but only requires the ability to perform. The examiner adds that
assuming arguendo that the language was considered to be a
limitation in a patentable sense, that the limitation is met
because for any converter, the ratio of the output to the input
Appeal No. 2001-1627
Application No. 09/289,420
Page 7
voltage is equal to, less than or greater than one. We find the
claim language to be a broad recitation of structure, and that to
meet the limitation, Cuk would have to be capable of meeting the
claimed ratio. We find that the language of the claim "equal to,
greater than, or less than one" is broad enough to read on the
entire set of real numbers, and that whatever the voltage ratio
is, it will inherently be in the ratio of "equal to, greater
than, or less than one." Accordingly, we consider this
limitation to be met by Cuk.
Appellant further argues (brief, page 11) that the
limitation regarding the recited alternative coils of a two-coil
inductor being employed in a primary and secondary loop, is not
met by the prior art. We note that the claim language does not
require that both coils are in each loop, but rather that one of
the alternative coils in one of the primary and secondary loops
and that the other coil is in the other of the primary and
secondary loops, as is shown for example in figure 3a of Cuk. In
any event, to the extent that claim 1 could be construed as
requiring that both coils are in each loop, we find this to be me
by virtue of switch S, which along with capacitor C1 connects
both loops or circuits. It is further argued (brief, pages 14
Appeal No. 2001-1627
Application No. 09/289,420
Page 8
and 15) that the limitation regarding non-electrically isolated
primary and secondary circuit loops is not met.
Appellant asserts (brief, page 15) that figure 3a of Cuk is
illustrative of appellant's position that the primary and
secondary circuit loops of Cuk are electrically isolated by C1,
Le, C2 and Vg, and that these circuits would prevent electrical
charge from flowing from L1 to L2. We find that Cuk discloses
(col. 2, lines 55-58) that “Fig. 6 illustrates one possible
realization of the present invention for a coupled-inductor
converter with dc isolation between the input (source) circuit
and multiple output (load) circuits.” Cuk additionally discloses
that "[b]ecause the coupled-inductor configurations of Fig. 1 and
Fig. 7 do not have the isolation property of the configuration of
Fig. 6 . . .."
We find from the disclosure of Cuk that in the embodiment of
figure 6, the primary and secondary circuit loops are
electrically isolated, but that in the embodiments of figures 1
and 7, the primary and secondary circuit loops are not
electrically isolated. Accordingly, we find this limitation of
claim 1 to be met by Cuk.
Appellant further argues (brief, page 16) that the
recitation in claim 1 that "the input and output voltages have
Appeal No. 2001-1627
Application No. 09/289,420
Page 9
the same polarity" is not met by Cuk as shown by the + and -
signs in the figures. The examiner asserts (answer, page 5) that
"all three reference have a positive voltage input and a positive
voltage output anticipating appellants claims."
From our review of Cuk, we agree with appellant that Cuk
discloses opposite polarity at the output of the converter than
the voltage at the input to the converter; see e.g., figure 7.
Accordingly, from all of the above, we find that Cuk does not
meet all of the limitations of claim 1. Accordingly, the
rejection of claim 1, and claims 2-18 dependent therefrom, under
35 U.S.C. § 102(b) is reversed. As independent claim 19
similarly requires that the input and output voltages have the
same polarity, the rejection of claim 19 and claims 20-25,
dependent therefrom, is reversed.
We turn next to the rejection of claims 1-31 under 35 U.S.C.
§ 102(b) as being clearly anticipated by Bang. The examiner's
rejection, in its entirety (final rejection, page 3) is that
"Bang discloses a surge protection circuit for a switching mode
power supply in figure 3." Appellant asserts (brief, pages 17
and 18) that Bang does not meet the claim limitations directed to
electrically isolated circuit loops; the use of an inductor in
Appeal No. 2001-1627
Application No. 09/289,420
Page 10
contrast to a power supply transformer, nor to an inductor
included in both a primary and secondary circuit loop.
With respect to the use of an inductor, we make reference to
our findings, supra, with respect to claim construction of claim
1 being broad enough to read on the two coils of an inductor that
is part of a transformer, as shown in figure 3 of Bang.
With respect to the inductor being included in both a
primary and secondary loop, as we found, supra, the language does
not require that each of the coils are in both circuit loops, but
rather reads on one coil of the inductor being in one circuit
loop and the other coil being in the other circuit loop.
Accordingly, we find two coil transformer T1 of Bang to meet this
limitation of claim 1. With regard to the limitation regarding
the non-electrical isolation of the primary and secondary circuit
loops, The examiner's position (final rejection, page 4) is that
"[f]rom applicant figure 1 it is clear that the capacitor is the
element that doesn't electrically isolated [sic] the two
windings. For the same reason the Yasumura and Bang references
are also not electrically isolated." The examiner additionally
asserts (answer, page 5) that “transformers are generally
electrically isolated. However, with applicants claimed
capacitor connection between the primary and secondary winding,
Appeal No. 2001-1627
Application No. 09/289,420
Page 11
the transformer was not electrically. Notwithstanding isolation,
all three of the cited prior art references show a capacitor
connected between the primary and secondary windings.” We
construe the examiner's position to be that transformers are
generally isolated, but that because the presence of appellant's
capacitor causes the windings to be considered as non-isolated,
that therefore, notwithstanding isolation, the prior art windings
are not isolated because they have capacitors between the coils.
Appellant's position (brief, page 18) is that the primary
and secondary circuit loops of Bang are electrically isolated.
It is argued that capacitors C1 and C2 are employed in the
circuit for surge suppression, and not to electrically couple the
primary and secondary circuit loops. Appellant adds (id.) that
“Capacitors are commonly employed to isolate circuit elements
and, for example, to suppress electrical surges. Therefore, the
presence of a capacitor, or capacitors, cannot meet this aspect
of claim 1.” Appellant additionally asserts (reply brief, page
5) that the lack of electrical isolation between primary and
secondary circuit loops is achieved, for example, by a switching
element, such as transistor 110.
From our review of Bang, we find that capacitors C1 and C2
snub bidirectional surge coupled between the drain terminal of Q1
Appeal No. 2001-1627
Application No. 09/289,420
Page 12
and the anode of diode D1 in snubber circuit 20, which absorbs
the peak value of the current surge (col. 2-9, 22-25, and 31-38).
We additionally find that the capacitors provide surge
protection, as advanced by appellant, and do not provide non-
isolation of the circuit loops. We agree with appellant that Bang
does not disclose non-isolation of the circuit loops, and
therefore find that Bang does not anticipate claim 1.
Accordingly, the rejection of claim 1, and claims 2-18 dependent
therefrom, under 35 U.S.C. § 102(b) is reversed. As independent
claim 19 also requires that the primary and secondary loop
circuit are not electrically isolated, the rejection of claim 19,
and claims 20-25, dependent therefrom under 35 U.S.C.
§ 102(b) is reversed.
We turn next to the rejection of independent claim 26. We
observe that claim 26 is the broadest of the three independent
claims. We make reference to our findings, supra, with respect
to the teaching of Bang. In addition, we find from figure 3 of
Bang that the polarity of the output voltage B+1 and B+2 is the
same relative polarity as the output voltage of voltage doubler
10. Although appellant asserts (reply brief, page 6) that all of
the cited patents have output voltages that are of opposite
relative polarity to their input voltages, appellant does not
Appeal No. 2001-1627
Application No. 09/289,420
Page 13
point to any portion of the disclosure of Bang to support
appellant's position. Thus, from all of the above, we find
nothing in the disclosure of Bang that would convince us of any
error in the examiner's position that the output and input
voltages of Bang have the same polarity. With respect to the
limitation of "an inductor included in both circuit loops,"
appellant asserts (brief, pages 18 and 19) that in appellant's
invention, coupled coils 162 and 164 are in both circuit loops
due to the presence of transistor 11. However, as we found,
supra, claim 26 is broad enough to read on one coil of the
inductor being in one loop and the other coil of the inductor
being in the other loop. We find this interpretation to be
consistent with the language of claim 27, dependent from claim
26, which recites that "wherein said conductor comprises a two-
coil conductor, one of said coils being in said primary loop and
one of said coils being in said secondary loop." Because claim
26 is broad enough to read on one of the coils being in each of
the loops, we find that this limitation is met by Bang.
In addition, due to the inherent nature of the transformer
T1 of Bang, we find that an input voltage is across the inductor
while the transformer charges and that an output voltage is
Appeal No. 2001-1627
Application No. 09/289,420
Page 14
across the inductor when the transformer discharges. Moreover,
in view of the inherent nature of the duty cycle generated by
switching driver 60 for at the gate of switching transformer Q1
(col. 4, lines 25-34) of Bang, we find that the primary and
secondary circuit loops conduct at different times.
From all of the above, we find that Bang anticipates claim
26. Accordingly, the rejection of claim 26 under 35 U.S.C. § 102
(b) is affirmed. As claims 27-31 fall with claim 26 (brief, page
8), the rejection of claims 27-31 under 35 U.S.C. § 102(b) is
affirmed.
We turn next to the rejection of claims 1-31 under 35 U.S.C.
§ 102(e) as being clearly anticipated by Yasumura. We begin with
Appeal No. 2001-1627
Application No. 09/289,420
Page 15
claim 1. Appellant asserts (brief, page 11) that Yasumura does
not meet the recited claim limitation directed to the use of an
inductor in contrast to a transformer. We make reference to our
construction of claim 1, supra. We find that the primary coil N1
and secondary coil Ni of MCT meet the claimed "two-coil inductor"
based upon our determinations, supra, with respect to the
construction of claim 1. Appellants argue (id.) that Yasumura
does not meet the claimed "input voltage ratio to output voltage
ratio capable of being equal to, greater than, or less than one."
The voltage ratios of Yasumura inherently meet this limitation
because whatever the ratio is, it is inherently within the set of
numbers defined by greater than one, equal to one or less than
one.
Appellant further argues that Yasumura does not meet the
claimed "alternative coils of a two-coil inductor are employed in
a primary and secondary circuit loop." We find that this
limitation is met by Yasumura based our findings, supra, with
respect to claim construction of claim 1.
It is further argued that the limitation regarding the
"input and output voltages having the same polarity" is not met.
We find from the disclosure of Yasumura that secondary winding Ni
Appeal No. 2001-1627
Application No. 09/289,420
Page 16
of a magnetic coupling transformer MCT are interposed in series
on the rectified output line between the positive terminal of a
bridge rectifying circuit D1 and that of smoothing condenser Ci
(col. 5, lines 29-32). Yasumura further discloses that the
polarity of the drive winding NB2 is opposite to that of drive
winding NB1 to produce a voltage of reverse polarity (col. 6,
lines 29-31). It is further disclosed that MCT transfers the
alternating voltage of the switching frequency generated by the
switching output to the secondary windings Ni through the
magnetic coupling. In addition, since the secondary winding Ni
is interposed on the positive output line from the bridge
rectifying circuit D1, the switching voltage transferred to the
secondary winding is superimposed to the rectified output voltage
on the rectifying path. Owing to the superimposition of the
switching voltage, the high speed recovery type rectifying diode
D2 interposed on the rectifying path switches on and off the
rectified current at the switching frequency (col.6, line 62
through col. 7, line 6). Moreover, Yasumura discloses (col. 7,
lines 57-65)
The voltage V1 between the connection point of the
high-speed recovery type rectifying diode D2 and
secondary winding Ni and the primary ground, which is
equivalent to the voltage across the secondary winding
Ni of the magnetic coupling transformer MCT, takes on a
waveform that the alternating voltage of the switching
Appeal No. 2001-1627
Application No. 09/289,420
Page 17
frequency is superimposed on the rectified output
voltage of the bridge rectifying circuit D1, as shown
in FIG. 2C.

From the disclosure of Yasumura that the positive terminal
is the output of the rectifying bridge D1; the showing of Ei in
figure 2C having positive polarity, and the positive polarity
shown in figure 1 at the input to the switching power circuit 1,
we find that the input and output voltages of figure 1 of
Yasumura are of the same polarity, as recited in claim 1.
It is further argued (reply brief, pages 5) that Yasumura
does not meet the claimed limitation that "the primary and
secondary circuit loops are not electrically isolated." From our
agreement with appellant, supra, that a capacitor will tend to
isolate, we agree with appellants (id.) that the capacitor C2
does not eliminate the isolation of the primary and secondary
circuit loops. However, because the output of the switching
voltage transferred to the secondary winding is superimposed on
the rectified output voltage on the rectified path, we find that
notwithstanding the presence of switching transistors Q1 and Q2,
that there is no clear teaching in Yasumura of the primary and
secondary circuits not being isolated, because Yasumura does not
disclose current flow between secondary winding Ni and switching
transistors Q1 and Q2. To find that Yasumura discloses non-
Appeal No. 2001-1627
Application No. 09/289,420
Page 18
isolated primary and secondary circuits, we would have to resort
to speculation, which we decline to do. See In re Warner, 379
F.2d 1011, 1017, 154 USPQ 173, 178 (CCPA 1967). Accordingly, we
find that the examiner has failed to establish a prima facie case
of anticipation of claim 1. The rejection of claim 1, and claims
2-18, dependent therefrom, under 35 U.S.C. § 102(e) is therefore
reversed.
We turn next to the rejection of claims 19-25. As
independent claim 19 also recites that "wherein said primary loop
and secondary loop circuits are not electrically isolated," the
rejection of claim 19, and claims 20-25, dependent therefrom,
under 35 U.S.C. § 102 (e) is reversed.
We turn next to independent claim 26. Claim 26 requires,
inter alia, that current is conducted through a primary and
secondary loop circuits at different times. The examiner has
provided no indication of how this limitation is considered to be
met by Yasumura. Appellant asserts (brief, page 13) that
appellant, having reviewed Yasumura, is unable to determine how
the document expressly or inherently meets this limitation.
We find that Yasumura discloses (col. 6, lines 45-47) that
when the self-excited switching operation starts, the switching
elements Q1 and Q2 go on alternatingly. In operation, the
Appeal No. 2001-1627
Application No. 09/289,420
Page 19
switching output is supplied to the primary winding N1 and MCT
transfers the alternating voltage of the of the switching
frequency generated by the switching output to the secondary
winding Ni through magnetic coupling (col. 6, lines 55-67). As
shown in figure 3, a switching operation by the switching
elements Q1 and Q2 is illustrated in the case of a switching
frequency of 100 kHz. The switching elements Q1 and Q2 repeat
ON/OFF operation alternatingly, and switching currents IC1, IC2
running across each collector and emitter assume the waveforms
shown in figures 3B and 3C, respectively. From the alternative
operation of switching elements Q1 and Q2, and the alternating
voltage generated by the switching output to the secondary
winding, we find that the primary and secondary circuits of
Yasumura conduct at the same time. From all of the above, we
find that the examiner has failed to establish a prima facie case
of anticipation of claim 26 by Yasumura. Accordingly, the
rejection of claim 26, and claims 27-31 dependent therefrom,
under 35 U.S.C. § 102(e) is reversed.
CONCLUSION
To summarize, the decision of the examiner to reject claims
1-31 under 35 U.S.C. § 102(e) as anticipated by Yasumura is
Appeal No. 2001-1627
Application No. 09/289,420
Page 20
reversed. The decision of the examiner to reject claims 1-25
under 35 U.S.C. § 102(b) as anticipated by Cuk is reversed. The
decision of the examiner to reject claims 1-25 under 35 U.S.C.
§ 102(b) as anticipated by Bang is reversed. The decision of the
examiner to reject claims 26-31 under 35 U.S.C. § 102(b) as
anticipated by Bang 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).
AFFIRMED-IN-PART
MICHAEL R. FLEMING )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
JOSEPH L. DIXON ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
STUART S. LEVY )
Administrative Patent Judge )
SSL/gjh
Appeal No. 2001-1627
Application No. 09/289,420
Page 21
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