Ex Parte Sickels et al

Patent Trial and Appeal Board

Feb 26, 2014

12030831 (P.T.A.B. Feb. 26, 2014)

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.
12/030,831 02/13/2008 Darrell L. Sickels 21125 (ITWO:0195) SWA 1456
52145 7590 02/27/2014
FLETCHER YODER (ILLINOIS TOOL WORKS INC.)
P.O. BOX 692289
HOUSTON, TX 77269-2289
EXAMINER
MEHARI, YEMANE
ART UNIT PAPER NUMBER
2838
MAIL DATE DELIVERY MODE
02/27/2014 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 PATENT TRIAL AND APPEAL BOARD
____________

Ex parte DARRELL L. SICKELS and BERNARD J. VOGEL

__________

Appeal 2011-013113
Application 12/030,831
Technology Center 2800
____________

Before CHARLES F. WARREN, MICHAEL P. COLAIANNI, and
DONNA M. PRAISS, Administrative Patent Judges.

PRAISS, Administrative Patent Judge.

DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134 the final rejection of claims
1-4, 6, 9-15, and 21-14. We have jurisdiction over the appeal pursuant to 35
U.S.C. § 6(b).
We REVERSE.
Appellants’ invention is said to be directed to a system and method
“for reducing capacitor ripple current in constant voltage welders” (Spec.
para. [0001]).
Claim 1 is illustrative (key limitations in dispute italicized):
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1. A welding system, comprising:
a rectifier circuit for converting AC power to DC power;
a DC bus having a high side and a low side, wherein the DC
bus is coupled to the rectifier to transmit the DC power;
a capacitive circuit coupled across the DC bus and configured
to smooth ripple in the DC power;
a first inductor coupled to one side of the DC bus; and
a second inductor coupled in series with the capacitive circuit
between the high side and the low side of the DC bus, and
wherein the second inductor is configured to limit rates of
current flow between the capacitive circuit and the DC bus
during operation.
App. Br. 16 (Claims App’x, emphasis added).
Appellants appeal the rejections under 35 U.S.C. § 103(a) of claims 1-
4, 6, 11-15, and 21-24 as being unpatentable over Reynolds (US 6,204,476
B1, issued Mar. 20, 2001) in view of Kooken (US 2007/0051712 A1,
published Mar. 8, 2007); claim 9 as being unpatentable over Reynolds in
view of Kooken, and further in view of Page (US 3,676,635 A, issued July
11, 1972); and claim 10 as being unpatentable over Reynolds in view of
Kooken and Page, and further in view of Bunker (US 7,078,652 B2, issued
Jul. 18, 2006).
Appellants separately argue independent claims 1, 11, and 21. App.
Br. 8-13. Regarding the remaining claims, Appellants rely on arguments
made regarding claims 1, 11, and 21. App. Br. 14-15. Accordingly, the
rejection of claims 2-4, 6, 9, and 10 will stand or fall with claim 1, the
rejection of claims 12-15 will stand or fall with claim 11, and the rejection of
claims 22-24 will stand or fall with claim 21. 37 C.F.R. § 41.37(c)(1)(vii).
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ISSUE
The dispositive issue in this appeal is whether the Examiner reversibly
erred in determining that Kooken teaches an inductor coupled in series with
a capacitive circuit between the high side and the low side of a DC bus as
required by independent claims 1, 11, and 21. We decide this issue in the
affirmative.

FINDINGS OF FACT AND ANALYSES
Claim 1
The Examiner finds that Reynolds teaches a welding system
comprising a rectifier circuit coupled to a DC bus having a first inductor
coupled to one side of the DC bus and a capacitive circuit coupled across the
DC bus. The Examiner further finds that “Madsen [sic, Reynolds] fails to
disclose a second inductor coupled in series with the capacitive circuit
between the high side and the low side of the DC bus . . . .” Ans. 3-4. The
Examiner relies on Kooken’s Figure 22 as teaching a second inductor (544)
coupled in series with the capacitive circuit (546) between the high side and
the low side of the DC bus (between 542 and 20b). Id. at 4.
The Examiner determines that “[i]t would have been obvious to one of
ordinary skill in the art at the time the invention was made to modify the
welding system of Reynolds et al. to include a capacitive circuit and an
inductor in series connection as taught by Kooken et al., because it helps in
stabilizing the output power.” Ans. 4.
Appellants argue that the Examiner erred in rejecting claim 1 because
the cited references lack features recited by the claim: “Reynolds and
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Kooken, alone or in combination, fail to teach or suggest a second inductor
coupled in series with a capacitive circuit between the high side and the low
side of the DC bus.” App. Br. 8 (emphasis in the original). Appellants do
not dispute that Kooken generally teaches inductor 544 in Figure 22, but
argue that Kooken’s inductor 544 is not between the high side and the low
side of a DC bus as required by the claim. Id. at 10. Appellants state that
“Kooken teaches that the inductor 544 is located on or in line with the high
side 20a (e.g., between first and second nodes on the high side 20a within
the path represented by reference number 542) of the DC bus rather than
between the high side 20a and the low side 20b of the DC bus, as recited by
independent claim 1.” Id.
The Examiner responds that “[t]he examiner is entitled to give the
broadest reasonable interpretation. Therefore, DC Bus 542 can be considered
as the high side bus, because it is higher than DC Bus 20a. The low side 20b
DC bus is a continuation of the DC Bus 534, and likewise, the high side DC
Bus 20a is the continuation of the DC Bus 542. Due to the inductor 544 the
DC potential on 542 is higher than the DC potential on 20a. Therefore, (534
or 20b) and 542 are the low and high side DC Buses respectively.” Ans. 11.
The preponderance of evidence supports Appellants’ position.
Appellants note that “if the Examiner’s interpretation of a recited claim term
is neither consistent with the specification, nor consistent with the
interpretation that one skilled in the art would reach, the interpretation
cannot be considered reasonable.” App. Br. 8.
Claim 1 recites “a DC bus having a high side and a low side.” Claim
1 further distinguishes between “a first inductor coupled to one side of the
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DC bus” and “a second inductor coupled in series with the capacitive circuit
between the high side and the low side of the DC bus.”
We look to Appellants’ Specification to properly construe the claim
limitation, “a DC bus having a high side and a low side.” Appellants disclose
that the DC bus 64 outputs DC power output 42 to welding torch 14. Spec.
¶¶ 0019-0021 and Figs. 1-2. The current from DC power output 42, via
welding torch 42, “form[s] an arc 22 from the electrode 16 to work piece 20”
and enables welding of the work piece. Spec. ¶ 0016 and Fig. 1. In other
words, the voltage across the DC bus 64 is connected to the welding
equipment and is the source of the welding arc.
The Examiner relies on Reynolds to teach a DC bus 76/74 that also
produces an output for a welding arc. Ans. 3. The Examiner further relies
on Reynolds to disclose a first inductor 58 coupled to one side of a DC bus
(i.e., along one side 76 in Fig. 2) and a capacitive circuit 56 coupled across
the DC bus (i.e., between sides 76 and 74). Id. Appellants do not dispute
these findings. App. Br. 10.
However, when the Examiner looks to Kooken to teach another
inductor in series with a capacitive circuit between the high side and the low
side of a related DC bus, the Examiner ignores Kooken’s teachings that
leads 20a and 20b form an output DC voltage. Instead, the Examiner
designates the voltage difference across line 542 and lead 20b as the recited
DC bus, wherein inductor 544 is located in between these two points. Ans.
4.
We agree with Appellants that one of ordinary skill in the art would
not reasonably find line 542 in combination with lead 20b a DC bus as
recited in claim 1. Certainly there is a measurable voltage difference across
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these two points in the circuit as there would be across other arbitrarily
chosen points in the circuit. But Kooken does not suggest using the voltage
difference between line 542 and lead 20b for any purpose, much less as an
output DC voltage for a welding power supply. On the contrary, as
Appellants point out, Kooken explicitly teaches connecting lead 20a and
lead 20b to further elements and thereby produce an output DC voltage:
“[T]he output terminals of the asserted DC bus (DC #2) clearly indicate a
high side of DC #2 as corresponding to 20a and a low side as corresponding
to 20b.” App. Br. 10. Appellants also refer to paragraph 0086 of Kooken
which specifically teaches “creat[ing] a DC voltage across (DC #2) leads
20a and 20b” and calls element 20 “DC bus 20” and “output bus 20.”
Kooken ¶ 0086; App. Br. 10.
The Examiner’s selection of line 542 and lead 20b in Kooken as the
DC bus recited in claim 1 is an unreasonable interpretation of the claim
limitation because it is inconsistent with the Specification. The
Specification describes DC bus 64 as having an output connected to and
used by the welding equipment. Spec. ¶¶ 0019-0021 and Figs. 1-2. The
Examiner’s finding that Kooken teaches an inductor between the high and
low sides of a DC bus is also inconsistent with Kooken’s disclosure of DC
bus 20 which comprises leads 20a and 20b. Kooken ¶ 0086. As discussed
supra, Kooken’s inductor 544 is located on one side 20a of bus 20, not
between sides 20a and 20b. Thus, the Examiner has not set forth a prima
facie case of obviousness of claim 1 over the combination of Reynolds in
view of Kooken.
On this record, we reverse the Examiner’s § 103 rejection of claim 1
and claims 2-10 which depend therefrom.
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Claims 11 and 21
Claim 11 recites “an inductor coupled in series with the capacitive
circuit and disposed between the high side of the DC bus and the capacitive
circuit.” App. Br. 17 (Claims App’x). Claim 21 recites “a second inductor
coupled between the first side and the second side of the DC bus in series
with the capacitor” (id. at 18). The Examiner relies on the same elements
542 and 20b in Kooken’s Figure 22 as teaching the claimed DC bus relative
to the location of the claimed inductor coupled in series with a capacitive
circuit and in combination with Reynolds for the rejection of independent
claims 11 (Ans. 5) and 12 (id. at 7) under 35 U.S.C. § 103(a).
For the same reasons discussed supra, the Examiner has not set forth a
prima facie case of obviousness for claims 11 and 21 over the combination
of Reynolds with Kooken.
On this record, we reverse the Examiner’s § 103 rejections of claims
11 and 21 as well as claims 12-15 and 22-24 which depend therefrom.

DECISION
The Examiner’s decision is reversed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136.

ORDER
REVERSED

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