Ex Parte Sakakibara

Patent Trial and Appeal Board

Sep 14, 2016

13001096 (P.T.A.B. Sep. 14, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/001,096 12/23/2010
127226 7590 09/16/2016
Birch, Stewart, Kolasch & Birch, LLP
P.O. Box 747
Falls Church, VA 22040-0747
FIRST NAMED INVENTOR
Kenichi Sakakibara
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
2257-0381PUS1 8961
EXAMINER
GRUBB, MATTHEW
ART UNIT PAPER NUMBER
2838
NOTIFICATION DATE DELIVERY MODE
09/16/2016 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):
mailroom@bskb.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KENICHI SAKAKIBARA
Appeal2015-000263
Application 13/001,096
Technology Center 2800
Before ROMULO H. DELMENDO, N. WHITNEY WILSON, and
AVEL YN M. ROSS, Administrative Patent Judges.
DELMENDO, Administrative Patent Judge.
DECISION ON APPEAL
The Applicant (hereinafter the "Appellant") 1 appeals under 35 U.S.C.
§ 134(a) from a final decision of the Primary Examiner to reject claims 5-
14.2 We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
1 The Appellant states that the real party in interest is "DAIKIN
INDUSTRIES, LTD." (Appeal Brief filed June 11, 2014, hereinafter
"Appeal Br.," 1 ).
2 Appeal Br. 3, 7; Final Office Action delivered electronically on September
9, 2013, hereinafter "Final Act.," 1-12).
Appeal2015-000263
Application 13/001,096
BACKGROl.J1'-JD
The subject matter on appeal relates to a power converter
(Specification, hereinafter "Spec.," i-f 1 ). Representative claim 5 is
reproduced from page 20 of the Appeal Brief (Claims App.), with key
limitations highlighted in italics, as follows:
5. A power converter, comprising:
a plurality of input lines applied with a polyphase AC
voltage;
a plurality of capacitors interposed between ones of said
plurality of input lines;
a first DC power supply line;
a second DC power supply line applied with a lower
potential compared with said first DC power supply line;
a converter comprising:
first diodes respectively provided correspondingly
to said plurality of input lines, each of said first diodes having
an anode connected to corresponding one side of said plurality
of input lines and a cathode connected to said first DC power
supply line side;
second diodes respectively provided
correspondingly to said plurality of input lines, each of said
second diodes having an anode connected to said second DC
power supply line side and a cathode connected to said
corresponding one side of said plurality of input lines; and
switch parts respectively provided correspondingly
to said plurality of input lines, selecting conduction/non-
conduction through said first diode between said corresponding
one of said plurality of input lines and said first DC power
supply line and conduction/non-conduction through said
second diode between said corresponding one of said plurality
of input lines and said second DC power supply line based on
external signals and bringing said corresponding one of said
plurality of input lines into conduction with said first and
second DC power supply lines in a state of not receiving said
signals; and
a clamp capacitor connected between said first and
second DC power supply lines.
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Application 13/001,096
THE REJECTIONS
The Examiner rejected the claims under 35 U.S.C. § 103(a) as
follows:
I. Claims 5-10 as unpatentable over Wei et al. (hereinafter "W ei")3
in view of Pond4, 5 ·
'
II. Claims 11-13 as unpatentable over Wei in view of Pond and Sato
et al. 6 ; and
III. Claim 14 as unpatentable over Wei in view of Pond and Kachi. 7
(Ans. 2---6; Final Act. 2-12.)
3 Lixiang Wei, et al., Matrix Converter Topologies with Reduced Number of
Switches, 1 PROC. OF PESC 57---63 (2002).
4 US 5,943,223 issued August 24, 1999.
5 Although not included in the statement of the rejection (see, e.g., In re
Hoch, 428 F.2d 1341, 1342 n.3 (CCPA 1970)), the Examiner also relied on
Toyoshima (US 2009/0128224 1A..l published l\1ay 21, 2009) "to provide
evidence that normally-on (depletion mode) switches were old and known at
the time of invention to provide a noise amount about an order of magnitude
smaller than that of enhancement mode switches over a broad frequency
region including the region (e.g., 5KHz) [in which] Wei's switches operate"
(Examiner's Answer delivered electronically on July 31, 2014, hereinafter
"Ans.," 2; see also Final Act. 3). In addition, the Examiner cited to Nair
(US 2005/0040792 Al published February 24, 2005) "as an evidentiary
reference that depletion mode JFETs were old and known at the time of
invention to provide beneficial characteristics such as a reduction in the
required silicon area while maintaining the electrical natures of other
conventional semiconductor switch parts" (id. at 6). Because the Appellant
does not raise any procedural issues but instead addresses the rejections on
the substantive merits (Appeal Br. 14, 18-19; Reply Brief filed September
29, 2014, hereinafter "Reply Br.," 1-8), we consider these references as part
of the relied-upon evidence.
6 US 5,764,496 issued June 9, 1998.
7 US 5,430,636 issued July 4, 1995.
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Application 13/001,096
DISCUSSION
Grouping of Claims
The Appellant's arguments are directed solely to claims 5 and 6,
which are subject to Rejection I (Appeal Br. 8-19). Therefore, except for
separately argued claim 6, all other claims subject to Rejection I (i.e., claims
7-10) stand or fall together with claim 5. See 37 C.F.R. § 41.37(c)(l)(iv).
In addition, because the Appellant relies on the same arguments for all three
rejections and claims 11-14 depend, either directly or indirectly, from claim
5, our ruling on claim 5 controls our decision as to Rejections II and III.
Claim 5
The Examiner found that Wei describes a power converter including
every limitation of claim 5 except "Wei is silent on the switch parts
[']bringing said corresponding one of said plurality of input lines into
conduction with said first and second DC power supply lines in a state of not
receiving said signals[']" as required by the claim (Final Act. 2-5). 8 The
Examiner found that, in contrast to the Appellant's claimed subject matter,
"Wei teaches using normally-off switches" (id. at 2). 9 The Examiner found
further, however, that Pond teaches a converter similar to Wei's converter
8 It appears that both the Appellant and the Examiner agree that the claim
limitations in dispute require "normally-on" switch parts (Appeal Br. 9;
Final Act. 2-5)
9 According to the Examiner, "Wei does not explicitly teach that the switch
parts are 'normally on' switches, but teaches that it is desirable that the
switches are on upon start-up to pre-charge the capacitors of the system" (id.
at 5) (citing Wei's Section IV, first bulleted item). The Examiner also found
that "Wei further describes a normal operation phase where the clamp
capacitor voltage is higher than Vdc (see e.g., Wei- Section IV, second
bullet), thus the clamp capacitor is not charged during normal operation
since it was charged during the start-up phase" (Ans. 3).
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Application 13/001,096
(Final Act. 5) and "Pond teaches that normally-on (depletion mode) switches
and normally-off (enhancement mode) switches are art recognized
equivalents as switch parts and may be optionally used in place of one
another" (Ans. 2) (citing Pond col. 8, 11. 17-21). The Examiner concluded
from these findings that "[i]t would have been obvious to one of ordinary
skill in the art . . . to modify the switch parts of Wei to include the depletion
or normally-on switch parts of Pond in order to take advantage of the
beneficial operating characteristics of depletion mode switches as taught by
Pond as desired" (Final Act. 5---6). As supporting evidence of these
"beneficial operating characteristics," the Examiner relied on Toyoshima,
which was found to teach that normally-on (depletion mode) switches
exhibit lower noise over a broad range of frequencies including the region in
which Wei's switches operate (Final Act. 3) (citing Toyoshima Fig. 6 and
ii 44).
The Appellant's principal argument is that the Examiner failed to
articulate a sufficient reason for providing normally-on switches in Wei
because "neither Pond nor Toyoshima describes a beneficial characteristic of
normally-on switches when installed in a power converter" (Appeal Br. 12).
According to the Appellant, "Toyoshima is directed to a completely different
technological field than the present invention (power converters)" (id.) and
"Toyoshima's disclosure is not reasonably pertinent to any problem
considered by Wei (or by [the] Appellant)" (id. at 14}-i.e., Toyoshima is
non-analogous art.
Because the Examiner failed to address the Appellant's argument
based on the two prongs of the non-analogous art test, we exclude
Toyoshima from the realm of applicable prior art. In re Clay, 966 F.2d 656,
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Application 13/001,096
658 (Fed. Cir. 1992) (explaining that the non-analogous art test considers the
threshold question whether a prior art reference is "'too remote to be treated
as prior art'") (quoting In re Sovish, 769 F.2d 738, 741 (Fed. Cir. 1985)).
Although we are constrained to agree with the Appellant as to
Toyoshima, we detect no reversible error in the Examiner's overall
conclusion that a person having ordinary skill in the art would have
combined Wei and Pond in the manner claimed by the Appellant. In re
Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011).
Specifically, Wei teaches that "[ w ]hen the converter is started, all the
switches in the line side tum on initially and the clamp capacitor voltage is
charged up to the maximum peak line voltage" (Section IV, first bulleted
item). Wei further teaches that "[u]nder normal operation, the clamp
capacitor voltage is higher than Vdc" and that "[h Jenee, the clamp diode is
reverse biased and this clamp circuit does not operate" (id., second bulleted
item). Wei states that "[ u ]nder a fault state, all switches in the converter are
turned off immediately" (emphasis added) and that "[t]he energy stored in
the inductive load flows into the clamp capacitor to avoid high voltage
spikes" (id., third bulleted item). Pond teaches a power converter, which is
structurally similar to that described in Wei, in which the MEM
(microelectromechanical) switches 18 can be either of the normally-open or
normally-closed type (Fig. 5; col. 8, 11. 17-24).
Given these facts, we discern no error in the Examiner's conclusion
that a person having ordinary skill in the art would have constructed Wei's
circuit to operate with normally-open switches based on the expectation that
either normally-open or normally-closed switches would work as
interchangeable components, as suggested in Pond. KSR Int 'l. Co. v.
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Application 13/001,096
Telej1ex Inc., 550 U.S. 398, 416 (2007) ("[W]hen a patent claims a structure
already known in the prior art that is altered by the mere substitution of one
element for another known in the field, the combination must do more than
yield a predictable result."). See also In re Fulton, 391F.3d1195, 1200
(Fed. Cir. 2004) ("[C]ase law does not require that a particular combination
must be the preferred, or the most desirable, combination described in the
prior art in order to provide [the] motivation [or reason] for the current
invention."); In re Mayne, 104 F.3d 1339, 1340 (Fed. Cir. 1997) ("Because
the applicants merely substituted one element known in the art for a known
equivalent, this court affirms [the rejection for obviousness]."); In re Fout,
675 F.2d 297, 301(CCPA1982) ("Express suggestion to substitute one
equivalent for another need not be present to render such substitution
obvious.").
The Appellant also argues that the Examiner's proposed modification
of Wei would impermissibly change Wei's principle of operation (Appeal
Br. 16). According to the Appellant, "if Wei's normally-off switches were
replaced with normally-on switches, when the clamp capacitor is pre-
charged to maximum peak line voltage, the normally-on switches would
immediately allow this charge to start leaking out, thus discharging the
clamp capacitor voltage below the desired level" (id. at 17).
The Appellant's argument is unpersuasive. The Examiner found that
"Wei teaches the use of blocking diodes in series with the line side switches
and the clamping capacitor, which [would] block the reverse discharge path"
(Ans. 5). That finding has not been refuted (Reply Br. 3-8). Moreover,
Pond teaches that normally-on switches have been successfully implemented
in similar power converters and, therefore, it would reasonably appear that
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Application 13/001,096
their implementation in Wei's circuit would have been within the creativity
and technical grasp of a person having ordinary skill in the art. KSR, 550
U.S. at 421.
The Appellant also argues that the prior art did not recognize the
source of a problem solved by the Appellant and that "the Examiner did not
consider [the] Appellant's discovery of the source of a problem" (Appeal Br.
17-18). We do not find this argument persuasive. First, the Supreme Court
of the United States criticized the approach that "patent examiners should
look only to the problem the patentee was trying to solve" and explained that
"[ u ]nder the correct analysis, any need or problem known in the field of
endeavor at the time of invention and addressed by the patent can provide a
reason for combining the elements in the manner claimed." KSR, 550 U.S.
at 420. Moreover, the Appellant's argument based on the discovery of a
problem and its solution is not substantiated by objective evidence (e.g.,
declaration evidence) and is therefore ineffective. See, e.g., In re Geisler,
116 F.3d 1465, 1470 (Fed. Cir. 1997) (mere lawyer's arguments and
conclusory statements, which are unsupported by concrete factual evidence,
are entitled to little probative value).
For these reasons, we uphold the Examiner's rejection of claim 5.
Claim 6
Claims 6 depends from claim 5 and recites the additional limitation
that "said switch parts include a junction field effect transistor [JFET]"
(Appeal Br. 20).
The Examiner found that "JFETs were old and known at the time of
invention to provide a normally-on type of switch (depletion)" (Final Act.
6). In support, the Examiner cited to Nair (i-f 3) "as an evidentiary reference"
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Application 13/001,096
(Ans. 6). The Examiner concluded that "[i]t would have been obvious to
one of ordinary skill in the art ... to modify Wei in view of Pond to include
JFE Ts instead of the IGBT in order to take advantage of the old and known
beneficial operating characteristics of JFETs" (Final Act. 6).
The Appellant argues that "[i]n the present invention, the use of a
junction field effect transistor can facilitate the use of wide-band-gap
devices of SiC, GaN, or the like as the switches, thereby improving control
performance and conversion efficiency" (Appeal Br. 18) (citing Spec. i-f 45).
In addition, the Appellant argues that "the Examiner has merely presented
conclusory statements ... without articulating any reason or rationale why
one of ordinary skill in the art would have used them in a power converter"
(id. at 19).
The Appellant's arguments are unpersuasive. First, the statement in
the Specification that JFETs can facilitate improved control performance and
conversion efficiency is not substantiated by any objective evidence (e.g.,
declaration evidence including comparative testing). Second, Nair discloses
that normally-on (depletion mode) switches may be provided in the form of
JFETs (i-f 3). Nair teaches (id.):
The benefit of a reduction in the required silicon area through
the use of a depletion mode JFET as the gating switch in a
battery pack application has been claimed. The depletion mode
device also resembles a MOSFET device in its electrical nature,
presenting high static impedance to the driving circuitry under
all conditions of this application.
Given that Wei and Pond would have suggested the use of normally-
on switches in a power converter, a person of ordinary skill in the art would
have found it obvious to provide such normally-on switches in the form of
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Application 13/001,096
JFETs with the reasonable expectation of obtaining their well-known
operational characteristics.
Accordingly, we also uphold the rejection of claim 6.
SUMMARY
The Examiner's final decision to reject claims 5-14 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)(l).
AFFIRMED
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