Ex Parte Briggs

Board of Patent Appeals and Interferences

Feb 26, 2010

10972234 (B.P.A.I. Feb. 26, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte MICHAEL D. BRIGGS
____________

Appeal 2009-004540
Application 10/972,234
Technology Center 3700
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Decided: February 26, 2010
____________

Before: WILLIAM F. PATE III, JENNIFER D. BAHR, and
LINDA E. HORNER, Administrative Patent Judges.

HORNER, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Michael D. Briggs (Appellant) seeks our review under 35 U.S.C.
§ 134 of the Examiner’s decision rejecting claims 5, 6, 8-10, 12, 13, 17, 21,
23, 24, 28, and 31-34. App. Br. 2 (Status of the Claims). We have
jurisdiction under 35 U.S.C. § 6(b) (2002).
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SUMMARY OF DECISION
We AFFIRM-IN-PART.

THE INVENTION
Appellant’s claimed invention relates to defogging/deicing aircraft
windshields. Spec. 1, para. 0002. Claim 1, reproduced below, is
representative of the subject matter on appeal.
1. An aircraft windshield defogging/deicing
system comprising:
a pair of transparent sheets maintained in
spaced facing relation by a transparent interlayer;
a resistive coating positioned between the
pair of transparent sheets; and
an inverter for applying a square wave or
quasi-square wave AC signal to the resistive
coating.

THE REJECTION
Appellant seeks review of the Examiner’s rejection of claims 5, 6,
8-10, 12, 13, 17, 21, 23, 24, 28, and 31-34 under 35 U.S.C. § 103(a) as
unpatentable over U.S. Patent 4,128,448 to Bitterice (issued Dec. 5, 1978),
U.S. Patent Publication 2003/0155467 A1 to Petrenko (published Aug. 21,
2003), and U.S. Patent Publication 2002/0089638 A1 to Ho (published Jul.
11, 2002).

ISSUES
The Examiner rejected claims 1-36 under 35 U.S.C. § 103(a) as
unpatentable over Bitterice, Petrenko, and Ho. Ans. 3-4. Appellant states
that appeal is taken from the examiner’s decision rejecting claims 1-36 but
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presents arguments for only claims 5, 6, 8-10, 12, 13, 17, 21, 23, 24, 28, and
31-34.1 As such, Appellant has waived any argument of error regarding the
rejection of claims 1-4, 7, 11, 14-16, 18-20, 22, 25-27, 29, 30, 35, and 36,
and we summarily sustain the rejection of these claims.
The Examiner found that Bitterice discloses the aircraft windshield
defogging/deicing system of independent claims 1 and 22, except that
Bitterice does not disclose use of an inverter power supply. Ans. 3. The
Examiner found that Petrenko teaches that an aircraft heating layer can be
powered via an inverter, dc-ac system, to afford use of a higher voltage to
power higher impedance coatings on windshields. Id. The Examiner found
that Ho discloses an inverter for applying a square wave alternating current
(AC) signal to the resistive coating of an aircraft display pane heating
system. Ans. 4. The Examiner concluded it would have been obvious to
modify Bitterice’s aircraft windshield defogging/deicing system to use an
inverter, as taught by Petrenko, for applying a square wave AC signal to the
resistive coating, as disclosed by Ho, because such a square wave AC power
supply was conventional, would quickly heat a glass pane, and was within
the level of ordinary skill in the art. Ans. 5, 6.
Appellant argues that the Examiner erred in the rejection of claims 5,
6, 8-10, 12, 13, 17, 21, 23, 24, 28, and 31-34 by failing to provide a
sufficient reason with a rational underpinning to explain why one having
ordinary skill in the art would have modified Bitterice to use Ho’s inverter as
a power supply to heat Bitterice’s resistive coating. Reply Br. 2-4.

1 Notice of Appeal dated June 14, 2007; App. Br. 2 (Status of Amendments).
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One issue before us is:
Is the proposed combination based upon a sufficient reason with a
rational underpinning to explain why one having ordinary skill in the art
would have modified Bitterice to use Petrenko’s inverter, as modified by the
square wave AC power supply as taught by Ho, to heat Bitterice’s resistive
coating?
Appellant raises additional issues through separate arguments that the
proposed combination does not meet every limitation of the appealed claims
as addressed in the Analysis section, infra.

FINDINGS OF FACT
We find that the following enumerated facts are supported by at least
a preponderance of the evidence. Ethicon, Inc. v. Quigg, 849 F.2d 1422,
1427 (Fed. Cir. 1988) (explaining the general evidentiary standard for
proceedings before the Office).
1. Ho discloses an indium tin oxide (ITO) heater 1 for electrical or
electronic components, such as liquid crystal displays (LCD). Ho
1, paras. 0001, 0013, 0019; figs. 1-3, 5. The LCD comprises: a
substrate 3 of transparent glass; a layer 4 of transparent conductive
material such as conductive, transparent ITO; and electrodes 5
having extensions 6 for connection with a source of alternating
applied voltage to actuate the heater to produce heat. Ho 1, paras.
0019, 0020; fig. 4.
2. Ho discloses the preferred voltage supply for the resistive coating
is square wave AC. Ho 1, para. 0020.
3. Ho discloses the “warm up” time needed for bringing the
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temperature of the LCD to the desired level is dependent upon: the
voltage applied (with greater power reducing “warm up” time), the
waveform applied, the mass of the transparent substrate, and the
temperature difference between the display and the surroundings.
Ho 2, para. 0027.
4. Ho discloses the device may be mounted in a vehicle, such as an
aircraft, or in the cold environment of an automobile dashboard
where the device is needed to maintain the display at a suitable
temperature. Ho 1, para. 0011; 2, paras. 0023, 0024.
5. Appellant’s Specification describes, in the “Description of Related
Art” that added weight is a known drawback in aircraft design.
Spec. 1, para. 0005.

ANALYSIS
Claims 5, 6, 8-10, 12, 13, 17, and 21 depend directly or indirectly
from claim 1, and claims 23, 24, 28, and 31-34 depend directly or indirectly
from claim 22. Despite Appellant’s failure to present arguments for the
patentability of independent claims 1 and 22, Appellant presents arguments
for the above-enumerated claims based on a limitation contained in claims 1
and 22, from which these claims depend. Because the claims before us for
review contain the limitation that the aircraft windshield defogging/deicing
system includes an inverter for applying a square wave or quasi-square wave
AC signal to the resistive coating, we address Appellant’s arguments
pertaining to this limitation.
Appellant argues that a person having ordinary skill in the art would
not have considered using Ho’s square wave AC power source in an aircraft
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windshield because LCD’s are smaller and require much less power than an
aircraft windshield defogger/deicer, and because Ho’s LCD operates in an
environment that is much less harsh than the operating environment of an
aircraft windshield. Reply Br. 3-4. We disagree.
Ho discloses an LCD screen heating device that, like the system of
Appellant’s claims, is comprised of layers of glass sandwiching a resistive
coating heated by AC (preferably a square wave) (Facts 1, 2). Ho’s device
quickly heats the glass of the display and can be used in a cold environment
such as a car dashboard (Facts 3, 4). The distinctions asserted by Appellant
(size and environment) appear to be nothing more than differences of
degree, rather than distinctions that would require Ho’s device, if used in an
aircraft windshield, to operate in a different manner. Further, Appellant has
not alleged that the proposed combination is beyond the skill of one having
ordinary skill in the art.
Appellant also argues that Ho does not disclose use of the power
supply to quickly heat the glass of the LCD display, and that Petrenko’s
disclosure of pulsed direct current (DC) directly contradicts use of an AC
square wave signal. Reply Br. 4. Again, we disagree.
Contrary to Appellant’s assertion, Ho discloses quick heating of the
glass (reduced “warm up” time) (Fact 3). Additionally, assuming, arguendo,
that Petrenko discloses use of sinusoidal AC and pulsed DC as a power
source, we fail to see how this disclosure would have led a person of
ordinary skill in the art in a direction divergent from that chosen by
Appellant to use square or quasi-square wave AC as a power source, because
Petrenko is simply disclosing alternatives to square wave AC, and does not
discourage use of square wave AC. In re Haruna, 249 F.3d 1327, 1335
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(Fed. Cir. 2001) (“A reference may be said to teach away when a person of
ordinary skill, upon reading the reference would be led in a direction
divergent from the path that was taken by the applicant.”). See also In re
Beattie, 974 F.2d 1309, 1312-13 (Fed. Cir. 1992) (A reference that discloses
one alternative is preferable to another is insufficient to teach away from a
combination using the non-preferred alternative).
Appellant’s arguments here fail to demonstrate error by the Examiner
in the rejection of claims 5, 6, 8-10, 12, 13, 17, 21, 23, 24, 28, and 31-34.
We now address Appellant’s additional arguments for patentability of each
claim as grouped by Appellant.
Claims 5, 6, 23, 24
Appellant argues claims 5, 6, 23, and 24 as a group. App. Br. 5-6.
We select claim 5 as the representative claim, and claims 6, 23, and 24 stand
or fall with claim 5. 37 C.F.R. § 41.37(c)(1)(vii) (2009).
Claim 5 depends from independent claim 1 and contains the further
limitation that the AC signal has a duty cycle ranging from 0% to 100% over
a 1 second time period, or a frequency ranging from 25 to 1000 Hertz.
Appellant’s Specification defines the duty cycle as “the ratio or percentage
of (a) the amount of time that power is delivered to the coating during a
specified period of continuous operation versus (b) the total specified period
of operation.” Spec. 7:10-13. Because claim 5 requires the AC signal to be
in the range from 0% (off) to 100% (on) over a 1 second time period, the
limitation simply requires that the AC signal be on or off during the claimed
time period. Further, because claim 5 calls for either the claimed duty cycle
or the claimed frequency range, the prior art must disclose only one of these
claimed parameters to render claim 5 obvious.
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Appellant’s argument (App. Br. 6) that Petrenko discloses use of a
pulse DC signal rather than an AC signal having duty cycle ranging from 0%
to 100% over a 1 second time period, is an unconvincing individual attack,
as the proposed combination uses Ho’s square wave AC signal. See Ans. 4;
see also, In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986); In re
Keller, 642 F.2d 413, 426 (CCPA 1981) (One cannot show nonobviousness
by attacking references individually where the rejections are based on
combinations of references).
Appellant has not demonstrated error in the rejection of claim 5, and
claims 6, 23, and 24 fall with claim 5.
Claims 8, 21, 28
Appellant argues claims 8, 21, and 28 as a group. App. Br. 6. We
select claim 8 as the representative claim, and claims 21 and 28 stand or fall
with claim 8. 37 C.F.R. § 41.37(c)(1)(vii). Claim 8 depends indirectly from
independent claim 1, and adds the limitation that the duty cycle of the AC
signal varies in response to windshield temperature as provided by a
temperature sensor.
Here, as with claim 5, supra, Appellant’s argument (App. Br. 6) that
Petrenko discloses varying the duty cycle of a pulse DC signal, not the duty
cycle of an AC signal, is an unconvincing individual attack, as the proposed
combination uses Ho’s square wave AC signal. See Ans. 4.
Claims 9 and 10
Appellant argues claims 9 and 10 as a group. App. Br. 6-7. We select
claim 9 as the representative claim, and claim 10 stands or falls with claim 9.
37 C.F.R. § 41.37(c)(1)(vii). Claim 9 depends indirectly from independent
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claim 1, and adds the limitation that the inverter weighs no more than 8
pounds.
Appellant’s contention that a person of ordinary skill in the art would
have selected an inverter in excess of 8 pounds assumes that a person of
ordinary skill in the art would not recognize that added weight is a detriment
to aircraft design, an assumption disproved by Appellant’s own
Specification (Fact 5). See App. Br. 6-7. A person of ordinary skill would
have recognized that minimizing the weight of the inverter would be an
important design consideration in creating an aircraft windshield
defogger/deicer. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007)
(It is proper to "take account of the inferences and creative steps that a
person of ordinary skill in the art would employ."). See also id. at 421 ("A
person of ordinary skill is also a person of ordinary creativity, not an
automaton.").
Further, we are unpersuaded by Appellant’s assertion (App. Br. 7-8)
that inverter power sources for aircraft windshield defogging/deicing
systems having a weight of no more than 8 pound were not available at the
time of Appellant’s claimed invention. Appellant could have submitted
evidence that inverters having a weight of no more than 8 pounds were not
available at the time of Appellant’s claimed invention, but chose not to
submit such evidence. In re Pearson, 494 F.2d 1399, 1405 (CCPA 1974)
(Appellant’s arguments do not take the place of evidence). Even were we to
accept Appellant’s assertion as true, Appellant has not asserted that inverters
having a weight of no more than 8 pounds did not exist for uses other than
aircraft defogger/deicers.
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The only distinction between the prior art and the subject matter of
claim 9 is that the prior art does not specify the weight of the inverter, as
claimed. Appellant does not allege any difference in function or unexpected
results using an inverter of no more than 8 pounds. See In re Soni, 54 F.3d
746, 750 (Fed. Cir. 1995) (“One way for a patent applicant to rebut a prima
facie case of obviousness is to make a showing of “unexpected results,” i.e.,
to show that the claimed invention exhibits some superior property or
advantage that a person of ordinary skill in the relevant art would have found
surprising or unexpected.).
Given the design need for lower aircraft weight, given that Appellant
has failed to establish inverters of no more than 8 pounds were unavailable
at the time of Appellant’s claimed invention, and given that Appellant has
failed to establish that design of an inverter of no more than 8 pounds was
beyond the skill level of a person having ordinary skill in the art, we
conclude that use of an inverter of no more than 8 pounds is merely routine
optimization of a result-effective variable and a matter of engineering design
within the skill level of one having ordinary skill in the art.
Claims 12 and 13
Claim 12 depends indirectly from independent claim 1, and adds the
limitation that the DC voltage has a value ranging from 24 to 32 volts, and
the AC voltage has a value ranging from 115-230 volts AC. The Examiner
concluded that the particular voltages used in claim 12 were routine choices
for the artisan dependent on the materials heated, the frequencies used, and
the temperatures encountered, and made no finding that the claimed DC and
AC voltages were known in the prior art Ans. 4.
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The Examiner fails to provide adequate reasoning as to what would
have led one having ordinary skill in the art to use voltages falling within the
claimed ranges in view of the prior art. See Ans. 4. “[R]ejections on
obviousness grounds cannot be sustained by mere conclusory statements;
instead, 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), quoting In re Kahn, 441 F.3d
977, 988 (Fed. Cir. 2006). As such, we cannot sustain the rejection of claim
12. The rejection of claim 13 is also in error by virtue of its dependence
from claim 12.
Claims 17 and 31
Appellant argues claims 17 and 31 as a group. App. Br. 8. We select
claim 17 as the representative claim, and claim 31 stands or falls with claim
17. 37 C.F.R. § 41.37(c)(1)(vii). Claim 17 depends from independent claim
1, adding the limitation that the resistive coating has a resistivity of no
greater than 50 ohms/square. Appellant acknowledges that Bitterice
discloses a resistive coating with a resistivity of less than 40 ohms/square.
App. Br. 8. Because a resistivity of less than 40 ohms/square meets the
limitation of no greater than 50 ohms/square, Appellant has not
demonstrated the Examiner erred in the rejection of claim 17. Claim 31 falls
with claim 17.
Claims 32, 33, and 34
Claim 32, depends from independent claim 22, and like claim 12, adds
the limitation that the DC voltage has a range between 24 and 32 volts, and
the AC voltage has a value ranging from 115-230 volts AC.
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Again, the Examiner fails to provide adequate reasoning as to what
would have led one having ordinary skill in the art to use voltages falling
within the claimed ranges in view of the prior art. See Ans. 4. In the
Examiner’s response, the Examiner finds that Petrenko discloses a window
de-icing system with an AC voltage range of 12-240 volts. Ans. 7-8. The
Examiner makes no finding regarding the DC voltage. For the reasons
explained in the analysis of claim 12, supra, we cannot agree that the
claimed voltages are a matter of design choice. We cannot sustain the
rejection of claims 33 and 34 by virtue of their dependence form claim 32.

CONCLUSION
The proposed combination is based upon a sufficient reason with a
rational underpinning to explain why one having ordinary skill in the art
would have modified Bitterice to use Petrenko’s inverter, as modified by the
square wave AC power supply as taught by Ho, to heat Bitterice’s resistive
coating.
DECISION
We AFFIRM the Examiner’s decision to reject claims 1-11, 14-31,
35, and 36.
We REVERSE the Examiner’s decision to reject claims 12, 13, 32,
33, and 34.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv) (2007).

AFFIRMED-IN-PART
Vsh
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INTELLECTUAL PROPERTY DEPT.
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PITTSBURGH, PA 15272