Ex Parte Stahlmann

Board of Patent Appeals and Interferences

May 4, 2009

11071853 (B.P.A.I. May. 4, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
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Ex parte DANIEL STAHLMAN
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Appeal 2009-1945
Application 11/071,853
Technology Center 2800
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Decided:1May 4, 2009
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Before TERRY J. OWENS, PETER F. KRATZ, and
KAREN M. HASTINGS, Administrative Patent Judges.

OWENS, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE
The Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s
rejection of claims 1-25, which are all of the pending claims. We have
jurisdiction under 35 U.S.C. § 6(b).

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, begins to run from the Decided Date
shown on this page of the decision. The time period does not run from the
Mail Date (paper delivery) or Notification Date (electronic delivery).

Appeal 2009-1945
Application 11/071,853

The Invention
The Appellant claims a level sensor and a method for using it to
determine the level of a conductive fluid. Claim 1 is illustrative:
1. A level sensor useful for determining a level of conductive fluid
within a container, comprising:

a conductive polymer element having a body with a three
dimensional exterior surface having a uniform distribution of carbon powder
at least along the exterior surface, the conductive polymer element is
adapted to be at least partially immersed in the fluid such that the fluid
establishes a conductive path between the conductive element and ground;
and
a controller that selectively energizes the conductive polymer
element and makes a level determination based upon an electrical output
corresponding to a dimension of a portion of the conductive polymer
element outside of the fluid.

The References
Williamson 5,626,053 May 6, 1997
Foisy 6,061,206 May 9, 2000
Kazkaz 6,634,229 B1 Oct. 21, 2003
The Rejections
The claims stand rejected as follows: claims 23 and 24 under
35 U.S.C. § 102(b) over Kazkaz; claim 25 under 35 U.S.C. § 103 over
Kazkaz; claims 1-4, 7, 9-12, 14-17, 19, 21 and 22 under 35 U.S.C. § 103
over Kazkaz in view of Williamson; claims 5, 6, 8 and 18 under
35 U.S.C. § 103 over Kazkaz in view of Williamson and Foisy; and
claims 13 and 20 under 35 U.S.C. § 103 over Kazkaz in view of Williamson
and the Appellant’s admitted prior art.
OPINION
We affirm the Examiner’s rejections.
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Application 11/071,853

Rejection of claims 23 and 24 under
35 U.S.C. § 102(b) over Kazkaz
The Appellant argues claims 23 and 24 as a group (Br. 7-8). We
therefore limit our discussion to one claim in that group, i.e., claim 23. See
37 C.F.R. § 41.37(c)(1)(vii) (2007).
Issue
Has the Appellant shown reversible error in the Examiner’s
determination that Kazkaz discloses, expressly or inherently, a purely AC
input?
Findings of Fact
Kazkaz discloses a non-floating fluid level sensor having an
alternating input signal circuit (90) (col. 1, ll. 12-13; col. 8, ll. 44-45).
Kazkaz’s exemplary alternating input signal circuit is a square wave
oscillator (col. 8, ll. 50-51).
Analysis
“Anticipation requires that every limitation of the claim in issue be
disclosed, either expressly or under principles of inherency, in a single prior
art reference.” Corning Glass Works v. Sumitomo Elec. U.S.A., Inc., 868
F.2d 1251, 1255-56 (Fed. Cir. 1989).
The Appellant argues (Br. 7):
The maximum and minimum voltages defined by the square wave will
always include a DC electrical energy component when viewed under
a segmented time frame T. At least some DC voltage is provided to
the semiconductive film strip 32 with the square wave oscillator as
disclosed in Kazkaz, et al. Therefore, the semiconductive film strip 32
of Kazkaz, et al. is not energized by a purely AC input.

The Examiner argues (Ans. 12):
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Application 11/071,853

While it is true that square-wave signals have small segments of time
in which the signal voltage is constant, the whole signal or wave is
still alternating with time. It is the signal input as a whole which is
being characterized, and the fact that it is a square wave signal does
not make its characteristic of being an alternating (AC) signal any less
pure.

The Examiner’s argument is reasonable and is not challenged by the
Appellant in the Reply Brief. Kazkaz’s disclosure that the square wave
oscillator is an alternating input signal circuit (col. 8, ll. 50-51) supports the
Examiner’s argument that Kazkaz’s input as a whole is a purely AC input.
The Appellant’s Specification merely states that “[i]n one example,
the controller energizes the conductive polymer element with a purely AC
input” (Spec. ¶ 0007). The Appellant’s Specification does not include any
description of the purely AC input that patentably distinguishes it over
Kazkaz’s alternating input signal.
The Appellant argues that “Kazkaz, et al. discloses an alternating
voltage source and not an alternating current signal” (Br. 8).
What the Appellant’s claim 23 requires is “a purely AC input”.
Kazkaz’s alternating input signal (col. 8, ll. 44-45) is a purely AC input.
Conclusion of Law
The Appellant has not shown reversible error in the Examiner’s
determination that Kazkaz discloses, expressly or inherently, a purely AC
input.
Rejection of claim 25 under 35 U.S.C. § 103 over Kazkaz
Issue
Has the Appellant shown reversible error in the Examiner’s
determination that Kazkaz would have rendered prima facie obvious, to one
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Application 11/071,853

of ordinary skill in the art, a conductive polymer element that is an extruded
piece?
Findings of Fact
Kazkaz’s fluid level sensor includes semiconductive film strips (32,
39), deposited onto a non-conductive substrate (34) and arranged generally
parallel to each other (col. 4, ll. 32-34, 51-52). Semiconductive film strip 32
is tapered from its wider upper end to its narrower lower end (col. 4, ll. 34-
38; Fig. 2). The semiconductive film strips can be formed of carbon or a
polymer (col. 7, ll. 13-14).
The Appellant argues (Br. 8-9):
It would be extremely difficult if not impossible to extrude the
conductive film strips 32, 40 of Kazkaz, et al. as a film due to their
nonuniform cross-section. Extrusion combined with necessary
secondary processing operations would be an extremely inefficient
manner of producing these film strips.

The Appellant’s claim limitation “the conductive polymer element is
an extruded piece” is a product-by-process limitation. The patentability of a
claim in product-by-process form is determined based on the product itself,
not on the method of making it. See In re Thorpe, 777 F.2d 695, 697 (Fed.
Cir. 1985) (“If the product in a product-by-process claim is the same as or
obvious from a product of the prior art, the claim is unpatentable even
though the prior art product was made by a different process.”). Whether a
rejection is under 35 U.S.C. § 102 or § 103, when the appellants’ product
and that of the prior art appear to be identical or substantially identical, the
burden shifts to the Appellants to provide evidence that the prior art product
does not necessarily or inherently possess the relied-upon characteristics of
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Application 11/071,853

the Appellants’ claimed product. See In re Fitzgerald, 619 F.2d 67, 70
(CCPA 1980); In re Best, 562 F.2d 1252, 1255 (CCPA 1977); In re
Fessmann, 489 F.2d 742, 745 (CCPA 1974). The reason is that the Patent
and Trademark Office is not able to manufacture and compare products. See
Best, 562 F.2d at 1255; In re Brown, 459 F.2d 531, 535 (CCPA 1972).
The Appellant’s claim 25 does not exclude an extruded piece that is
subsequently cut into a desired shape such as the shape of Kazkaz’s
polymeric semiconductive film strip 32 (Fig. 2). Because it appears that
Kazkaz’s polymeric semiconductive film strip 32 is identical or substantially
identical to an extruded piece cut to its shape, the burden has shifted to the
Appellant to provide evidence to the contrary. As indicated by the Examiner
(Ans. 13), the Appellant has not carried that burden.
Conclusion of Law
The Appellant has not shown reversible error in the Examiner’s
determination that Kazkaz would have rendered prima facie obvious, to one
of ordinary skill in the art, a conductive polymer element that is an extruded
piece.
Rejection of claims 1-4, 7, 9-12, 14-17, 19, 21 and 22 under
35 U.S.C. § 103 over Kazkaz in view of Williamson
Issue
Has the Appellant shown reversible error in the Examiner’s
determination that Kazkaz and Williamson would have rendered prima facie
obvious, to one of ordinary skill in the art, a conductive polymer element
having a uniform distribution of carbon powder at least along its exterior
surface?

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Application 11/071,853

Findings of Fact
Williamson discloses a floatless gauge which “is particularly useful
for measuring the liquid level of partially conductive and conductive fluids
which can support corrosion” (col. 1, ll. 12-15). The gauge includes
resistive/conductive polymeric elongate members (30, 40) (col. 3, ll. 28-34).
“Suitable resistive/conductive polymeric materials include thermoplastic
polymeric polyesters or other thermoplastics containing carbon fibers or
carbon particles” (col. 5, ll. 27-29). The benefits of the resistive/conductive
polymeric materials include: 1) they “can provide useful resistance values in
relatively large cross sections, thus providing superb mechanical strength
without the need for additional structures” (col. 6, ll. 21-24), and 2) a gauge
made of the resistive/conductive polymeric materials “may be added to the
tank after completion, and the length of resistive member can be easily
varied to be used in tanks of different depths” (col. 8, ll. 56-59).
Analysis
The Appellant argues that Kazkaz discloses use of the fluid level
system in such non-harsh environments as a washing machine basin, and
that nothing in Kazkaz would have suggested using, in Kazkaz’s system,
Williamson’s carbon fiber or carbon particle-containing thermoplastics
which, the Appellant argues, are “designed for use within highly conductive
fluids such as battery acid, other strong acids and strong gases (see
column 3, lines 11-13)” (Br. 5; Reply Br. 1-2).
In the two sentences before the one relied upon by the Appellant,
Williamson discloses that the gauge will operate in partially conductive
fluids, examples of which “include tap water, coffee, and radiator coolant
mixtures” (col. 3, ll. 6-10). Thus, the Appellant’s argument that one of
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Application 11/071,853

ordinary skill in the art would have considered Williamson’s carbon fiber or
carbon particle-containing thermoplastics to be useful only in harsh
environments is not well taken.
Moreover, Williamson discloses that the gauge is useful in fluids
which can support corrosion and that such fluids include tap water (col. 1, ll.
13-15, 26-29). That disclosure would have indicated to one of ordinary skill
in the art that Williamson’s carbon fiber or carbon particle-containing
thermoplastics would be well suited for use in Kazkaz’s washing machine
basins which, due to containing detergents and soiled clothes in addition to
tap water, are a more harsh environment than pure tap water.
Furthermore, Kazkaz does not limit the system to non-harsh
environments but, rather, discloses that it may be used “in any application
where it is desirable to sense or detect, and in some embodiments to control,
fluid level in a container” (col. 3, ll. 32-35).
In addition, Williamson’s disclosures that the conductive polymeric
materials “can provide useful resistance values in relatively large cross
sections, thus providing superb mechanical strength without the need for
additional structures” (col. 6, ll. 21-24) and permit the length of the resistive
member to be easily varied for use in tanks of different depths (col. 8, ll. 56-
59) would have led one of ordinary skill in the art to use Williamson’s
carbon fiber or carbon particle-containing thermoplastics in Kazkaz’s fluid
level sensing system to provide those benefits. See KSR Int’l. Co. v. Teleflex
Inc., 550 U.S. 398, 417 (2007) (“[I]f a technique has been used to improve
one device, and a person of ordinary skill in the art would recognize that it
would improve similar devices in the same way, using the technique is
obvious unless its actual application is beyond his or her skill”).
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Application 11/071,853

Conclusion of Law
The Appellant has not shown reversible error in the Examiner’s
determination that Kazkaz and Williamson would have rendered prima facie
obvious, to one of ordinary skill in the art, a conductive polymer element
having a uniform distribution of carbon powder at least along its exterior
surface.
Rejection of claims 5, 6, 8 and 18 under 35 U.S.C. § 103
over Kazkaz in view of Williamson and Foisy
Issue
Has the Appellant shown reversible error in the Examiner’s
determination that the applied prior art would have rendered prima facie
obvious, to one of ordinary skill in the art, the use of an amount of carbon in
Williamson’s carbon fiber or carbon particle-containing thermoplastics to
provide the desired conductivity?
Findings of Fact
Foisy discloses a plastic E-block (30) as part of a hard disk drive head
stack assembly (col. 1, ll. 8-11; col. 7, ll. 7-13). “Plastic E-block 30 is
fabricated from a first thermoplastic material containing electrically
conductive filler material such that the E-block is electrically conductive”
(col. 7, ll. 10-13). The plastic can be polyphthalamide and the conductive
filler can be carbon, preferably in an amount of about 15 to about 60 percent
of the mass of the E-block (col. 7, ll. 15-18). “As the percentage [of carbon]
increases, the stiffness and the conductivity of the plastic E-block increase”
(col. 7, ll. 18-19).
Analysis
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Application 11/071,853

The Examiner argues that in view of Foisy, one of ordinary skill in the
art would have used, in Williamson’s carbon fiber or carbon particle-
containing thermoplastics, an amount of carbon to provide the desired
conductivity depending upon the fluid and particular application (Ans. 7,
10).
The Appellant argues that “[i]t is not clear, and the Examiner fails to
describe, how adding conductive filling material to a plastic e-block is the
same as Applicant’s claimed conductive polymer element having a uniform
distribution of carbon powder or varying percentages” (Br. 6).
The Examiner does not argue that adding conductive material to an
E-block is the same as adding conductive material to the Appellant’s
conductive polymer element. The Examiner’s argument is that, given the
teaching by Foisy of adding conductive material, i.e., carbon, to a plastic in
an amount such as about 15 to about 60% to adjust the conductivity, one of
ordinary skill in the art would have selected an appropriate amount of carbon
in Williamson’s carbon fiber or carbon particle-containing thermoplastics to
provide the desired conductivity (Ans. 7, 10). That argument is reasonable
and the Appellant has not explained why it is incorrect.
Conclusion of Law
The Appellant has not shown reversible error in the Examiner’s
determination that the applied prior art would have rendered prima facie
obvious, to one of ordinary skill in the art, the use of an amount of carbon in
Williamson’s carbon fiber or carbon particle-containing thermoplastics to
provide the desired conductivity.

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Appeal 2009-1945
Application 11/071,853

Rejection of claims 13 and 20 under 35 U.S.C. § 103
over Kazkaz in view of Williamson and
the Appellant’s admitted prior art
The Appellant does not provide a substantive argument for the
separate patentability of claims 13 and 20 (Br. 6). Hence, for the reasons
given regarding claim 1 from which claim 13 depends, and claim 15 from
which claim 20 depends, we are not convinced of reversible error in the
rejection of claims 13 and 20.
DECISION/ORDER
The rejections of claims 23 and 24 under 35 U.S.C. § 102(b) over
Kazkaz, claim 25 under 35 U.S.C. § 103 over Kazkaz, claims 1-4, 7, 9-12,
14-17, 19, 21 and 22 under 35 U.S.C. § 103 over Kazkaz in view of
Williamson, claims 5, 6, 8 and 18 under 35 U.S.C. § 103 over Kazkaz in
view of Williamson and Foisy, and claims 13 and 20 under 35 U.S.C. § 103
over Kazkaz in view of Williamson and the Appellant’s admitted prior art
are affirmed.
It is ordered that the Examiner’s decision 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

tc

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