Ex Parte Prinssen

Board of Patent Appeals and Interferences

Jul 17, 2000

08324386 (B.P.A.I. Jul. 17, 2000)

THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered today
(1) was not written for publication in a law journal and
(2) is not binding precedent of the Board.
Paper No. 34
UNITED STATES PATENT AND TRADEMARK OFFICE
_____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_____________
Ex parte ALPHONS A. J. A. PRINSSEN
_____________
Appeal No. 1997-3267
Application 08/324,386
______________
ON BRIEF
_______________
Before COHEN, FRANKFORT and JENNIFER D. BAHR, Administrative
Patent Judges.
FRANKFORT, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on an appeal from the examiner’s
Appeal No. 1997-3267
Application 08/324,386
the final rejection in a paper filed May 6, 1996 (Paper No. 25).
Claims 1 through 3 have been canceled.
Appellant’s invention pertains to a filtering device
and method using a high pressure chamber for separating liquid
and solid material from a mixture wherein a component of the
mixture can pass into a gaseous phase at ambient temperature and
atmospheric pressure. By placing the mixture being separated
under a higher pressure than the lowest evaporation pressure of
any of the mixture’s components, no component of the mixture can
pass to the gaseous phase. Independent claims 4, 7 and 10 are
representative of the subject matter on appeal and copies of
these claims, as reproduced from the Appendix of appellant’s1
amendment after final (Paper No. 25, filed May 6, 1996), are
attached to this decision.
Appeal No. 1997-3267
Application 08/324,386
The references of record relied upon by the examiner
in support of rejections under 35 U.S.C. § 102(b) and 35 U.S.C.
§ 103 are:
Oosten 4,038,193 July 26, 1977
Stahl 2,947,329 May 27, 19812
(German Offenlegungsschrift)
Claims 4 through 6 stand rejected under 35 U.S.C.
§ 112, first paragraph, as failing to provide support for the
invention now claimed.
Claims 4 and 6 stand rejected under 35 U.S.C. § 102(b)
as being anticipated by Stahl.
Claims 5, 7, 8 and 10 stand rejected under 35 U.S.C.
§ 103 as being unpatentable in view of Stahl.
Claims 9 and 11 stand rejected under 35 U.S.C. § 103
as being unpatentable over Stahl in view of Oosten.
Appeal No. 1997-3267
Application 08/324,386
Rather than reiterate the examiner's full statement
of the above-noted rejections and the conflicting viewpoints
advanced by the examiner and appellant regarding the rejections,
we make reference to the examiner's answer (Paper No. 22, mailed
January 30, 1996) and the examiner's supplemental answer
(Paper No. 31, mailed August 6, 1996) for the reasoning in
support of the rejections, and to appellant’s brief (Paper
No. 21, filed January 11, 1996), and reply briefs (Paper No. 23,
filed March 21, 1996 and Paper No. 30 filed July 26, 1996) for
the arguments thereagainst.
OPINION
In reaching our decision in this appeal, we have given
careful consideration to appellant’s specification and claims, to
the applied prior art references, and to the respective positions
articulated by appellant and the examiner. As a consequence of
our review, we have made the determinations which follow.
Preliminary to treating the examiner’s rejections of
Appeal No. 1997-3267
Application 08/324,386
and 6 stand or fall together, that claims 8 and 10 stand or fall
together, that claims 9 and 11 stand or fall together and that
claims 5 and 7 each stand or fall alone.
We will first address the rejection of claims 4
through 6 under 35 U.S.C. § 112, first paragraph. The examiner
objects to the specification as originally filed for failing to
provide a basis for “the mixture of liquid and solid materials
[being] added into the filter box at a pressure higher than
atmospheric” (answer, page 3). As a result of the objection, the
examiner rejects claims 4 through 6 under 35 U.S.C. § 112, first
paragraph, which claims include the limitation of supplying a
mixture of liquid and solid materials at higher than atmospheric
pressure into the pressure chamber on an upper side of said
filter belt. The appellant’s argument, in response, is that
one of ordinary skill in the art would
understand from the specification that the
mixture for separation is maintained under
relatively higher pressure both when supplied
to the pressure chamber and within the
pressure chamber itself. The fact that there
may be other methods of supplying the mixture
Appeal No. 1997-3267
Application 08/324,386
We agree with the appellant. Although, arguably, there
may be other methods of supplying the mixture to the pressure
chamber, we believe that a person of ordinary skill in the art
would have known that any method for feeding the mixture into
the high pressure chamber of the appellant’s claimed method and
device would necessarily require forcing the mixture into the
high pressure chamber at a pressure the same as or slightly
higher than the pressure maintained in the chamber to allow for
adequate forward flow of the mixture into the chamber. The
mixture could not enter the chamber at a lower pressure than
that maintained in the chamber since the force of the pressurized
air at the mixture inlet would obstruct entry of the mixture into
the chamber. Therefore, we reverse the examiner’s rejection of
claims 4 through 6 under 35 U.S.C. § 112, first paragraph.
Next, we will address the rejection of claims 4 and 6
under 35 U.S.C. § 102(b) based on Stahl. Stahl teaches an
arrangement and method for filtration including a pressurizing
source (26), a vacuum chamber or suction box (23) and a source
Appeal No. 1997-3267
Application 08/324,386
in a closed space under a positive pressure with respect to the
open air” (translation, page 5) and “feeding of the filter in the
arrangement . . . can be done . . . [with] the aid of pumps . . .
such that the positive pressure in the positive pressure chamber
is taken into account” (translation, page 7). Stahl further
shows, in Figure 2, an embodiment having a “product space [that]
is kept higher than atmospheric pressure” and where it is
“preferable to use an arrangement which is distinguished by the
fact that the pressure difference between the space kept under
positive pressure and the product space in a subterranean tunnel
can be adjusted up to a maximum value which can be selected
exclusively according to the requirements of the filtration
problem” (translation, page 7). The appellant argues that there
is no teaching or suggestion within Stahl for supplying the
feedstock (25) to the enclosed pressure space at a pressure
greater than atmospheric and that it is clear that the material
to be separated is only subjected to the positive pressure when
in the positive pressure chamber and not in the prior supply
portions, hence the need for the supply pumps to take the
Appeal No. 1997-3267
Application 08/324,386
We do not find appellant’s arguments convincing.
Stahl teaches the mixture (suspension feedstock 25) being fed
through the pressure resistant wall (29') without problems and
in the usual manner with pumps in order to deliver the mixture
to the belt filter (20) (translation, pages 7 and 12). We are
convinced that a person of ordinary skill in the art would have
understood from the specification of Stahl that the mixture for
separation is maintained under higher pressure than atmospheric
when supplied to a chamber pressurized to above atmospheric
pressure to thereby prevent backflow. Ultimately, we consider
that an artisan would have understood the mechanism for supplying
the mixture to the pressurized chamber of the prior art to
operate in the same manner that we have concluded supra was
implicitly disclosed by the appellant’s specification. There-
fore, we will affirm the examiner’s rejection of claims 4 and 6
under 35 U.S.C. § 102(b) as anticipated by Stahl.
Next, we will address the rejection of claims 5, 7, 8
and 10 under 35 U.S.C. § 103(a) based on Stahl. Claim 5 depends
Appeal No. 1997-3267
Application 08/324,386
pressure difference between the pressure in the pressure chamber
and the pressure in the suction box being “roughly 1-2 bar.” We3
agree with the examiner’s position that the 20 bar parameter in
combination with a pressure difference of 1-2 bar is one which
“would have been routinely optimized by one having ordinary skill
in the art at the time the invention was made” (answer, page 4).

The appellant argues that there is no suggestion in
Stahl to utilize the very high pressure of 20 bar and moreover to
utilize both an exceptionally high pressure of 20 bar in the
pressure chamber and a difference between the pressure in the
pressure chamber and the pressure in the suction box of 1-2 bar.
The appellant understands Stahl to teach (brief, pages 9-11) a
pressure chamber intended to be raised to only slightly elevated
pressures instead of the 20 bar required in the pressure chamber
as set forth in claim 5 on appeal. Furthermore, the appellant
argues that Stahl is limited to slightly elevated pressures since
Stahl teaches a product space to be maintained under atmospheric
pressure and thus a positive pressure of only 1.5 bar which
Appeal No. 1997-3267
Application 08/324,386
We do not agree with the appellant’s interpretation of
the prior art. First, we do not find that Stahl teaches only a
product space at below atmospheric pressure as suggested by
appellant throughout the briefs. Nor, do we understand Stahl
to “clearly indicate[] that the pressure difference between the
slightly elevated positive pressure in the pressure chamber and
the subatmospheric pressure in the product space can be selected
according to [the] filtration problem[]” (emphasis ours) (reply
brief, Paper No. 23, page 4). Appellant repeatedly contends
that Stahl indicates that the pressure is only slightly elevated
without any reference to a specific passage in Stahl teaching
such limitation. We find no such limiting teaching in Stahl.
With respect to the embodiment shown in Figure 2, Stahl
specifically states that the pressure differential between the
space under positive pressure and the product space can be
adjusted up to a maximum value that can be selected exclusively
according to the requirements of the filtration problem (trans-
lation, pages 3 and 7). Throughout the specification, as
Appeal No. 1997-3267
Application 08/324,386
space are adjustable. Some examples are: on page 5, “a product
space under a specifiable pressure”; on page 8, “the crucial
product space is kept either at atmospheric pressure or at a
pressure higher or lower than atmospheric pressure”; and on
page 9 “the positive pressure can be adjusted according to
requirements" and "the desired pressure differential can be
adjusted independently of one another.” Furthermore, Stahl
specifically teaches appellant’s limitation of a pressure
differential of 1-2 bar on pages 5-6 of the translation. We
further understand Stahl to teach a closed system where the
positive pressure and the pressure at the vacuum filter is
settable to any pressure known in the art to solve a particular
filtration problem. Specifically, claim 11 of Stahl, rewritten
to include all the limitations of the claims from which it
depends, is as follows:
Arrangement for filtration, in which
in a filter constructed in its design as a
vacuum filter, solid particles are to be
filtered out of a fluid with the assistance
of a porous material layer, in particular a
filter cloth serving as filtering means,
characterized in that the entire vacuum
Appeal No. 1997-3267
Application 08/324,386
. . . the product space is kept at a pressure
higher than atmospheric pressure [,] . . .
the pressure differential between the space
(46) under positive pressure and the product
space can be adjusted in a tunnel arranged
underground, up to a maximum value that can
be selected exclusively according to the
requirements of the filtration problem.
Finally, Stahl teaches that a benefit of his arrangement is that
“the attainable positive pressure in an arrangement for cake
formation and suction drying . . . is no longer absolutely
limited by the vapor pressure. Rather, the positive pressure
can be adjusted according to the requirements [of the filtration
problem]” (translation, page 9). Therefore, we concur with the
examiner that a person of ordinary skill in the art would have
known to select a positive pressure, including 20 bar, to
optimize solving a particular filtration problem while main-
taining a pressure differential within the range of 1-2 bar. We
find the examiner’s position to be well founded, notwithstanding
appellant’s arguments to the contrary. Therefore, we will affirm
the examiner’s rejection of claim 5.
Appeal No. 1997-3267
Application 08/324,386
broader than claim 5 since it does not require the mixture to be
fed into the chamber at higher than atmospheric pressure and does
not require the pressure difference to be 1-2 bar but only to be
“relatively small.” Therefore, we will affirm the examiner’s
rejection of claim 7 applying our same reasoning used in sus-
taining the rejection of claim 5. Claim 8, which depends from
claim 7, includes the pressure difference to be 1-2 bar which
has been previously discussed and shown to be taught or suggested
in Stahl. Therefore, we will also sustain the examiner’s rejec-
tion of claim 8 applying the rationale set forth with respect to
claim 5. Appellant has stated on the record that claim 10 falls
with claim 8 and therefore we will affirm the examiner’s rejec-
tion of claim 10.
Finally, we will address the rejection of dependent
claims 9 and 11 under 35 U.S.C. § 103(a) based on Stahl in view
of Oosten. Claim 9 includes the additional method limitations of
the suction box 1) creating a pressure differential between the
pressure in the suction box and pressure in the pressure chamber
Appeal No. 1997-3267
Application 08/324,386
connected to the filter belt, 3) increasing the pressure in the
suction box to decouple the suction box and the filter belt and
4) moving the suction box relative to the pressure chamber to
return the suction box to the first position. Claim 9 also
includes a fifth step which repeats steps 1-4. Appellant’s
primary argument (brief, page 13) concerning the examiner’s
rejection relies on Stahl and Oosten teaching the suction box
being maintained at below atmospheric pressure, which in appel-
lant's view teaches away from appellant’s filtration device and
method as defined in claims 9 and 11 on appeal.
We believe the appellant has not fairly assessed the
collective teachings of the applied prior art. As previously
discussed, Stahl expressly teaches the vacuum or product space
being at a pressure above atmospheric. Oosten teaches
FIGS. 1a, b, c and d show the operation of a
device in accordance with the known art. A
mixture supply nozzle 1 applies a mixture
layer 2 to an endless filter belt 3, which is
guided along rollers 4 and 5 to be driven. A
suction box 6, adapted to move parallel to
the belt, communicates through a flexible
Appeal No. 1997-3267
Application 08/324,386
the arrow. At the end of the suction stroke
as illustrated in FIG. 1b, the subatmospheric
pressure is obviated by the supply of air so
that the filter belt and the suction box are
disengaged and the suction box is returned
by a mechanism (not shown) to the initial
position (column 1, line 62, through
column 2, line 9).
Although Oosten teaches the vacuum being at below atmospheric
pressure, Oosten also teaches at column 3, lines 6-8, “[t]he
whole device may be surrounded by a cabinet (not shown) for
operation, for example, in a nitrogen atmosphere, for example,
at excess pressure.”
We are not convinced by appellant’s argument that Stahl
and Oosten teach away from the device and method claimed by the
appellant. Both references teach a closed system at excess or
positive pressure. We conclude that a person of ordinary skill
in the art would have been led to the appellant’s invention of
claim 9 given the collective teachings of the applied prior art.
Therefore, we will sustain the examiner’s rejection of claim 9.
The examiner’s rejection of claim 11 which falls with claim 9
Appeal No. 1997-3267
Application 08/324,386
To summarize, the examiner’s rejection of claims 4
through 6 under 35 U.S.C. § 112, first paragraph, has been
reversed. The examiner’s prior art rejections of claims 4
through 11 are affirmed. Accordingly, the decision of the
examiner is affirmed.
No time period for taking any subsequent action
in connection with this appeal may be extended under 37 CFR
§ 1.136(a).
AFFIRMED
IRWIN CHARLES COHEN )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
CHARLES E. FRANKFORT ) APPEALS AND
Administrative Patent Judge ) INTERFERENCES
)
)
)
Appeal No. 1997-3267
Application 08/324,386
Russell D. Orkin
Webb, Ziesenheim, Bruening, Logsdon, Orkin & Hanson
700 Koppers Building
436 7th Avenue
Pittsburgh, PA 15219-1818
Appeal No. 1997-3267
Application 08/324,386
APPENDED CLAIMS
4. A filtration method for separating liquid and solid
materials from a mixture, comprising the steps of:
providing a pressure chamber containing an endless
filter belt and a suction box;
supplying a mixture of liquid and solid materials at
higher than atmospheric pressure into said pressure chamber on an
upper side of said filter belt;
connecting said suction box onto an underside of said
filter belt; and
maintaining a higher than atmospheric pressure in said
pressure chamber and a relatively small difference between the
pressure in said pressure chamber and the pressure in said
suction box.
7. A filtration method for separating liquid and solid
materials from a mixture, comprising the steps of:
providing a pressure chamber containing an endless
filter belt and a suction box therein;
supplying a mixture of liquid and solid materials on a
first side of said filter belt;
connecting said suction box to an underside of said
filter belt; and
maintaining a higher than atmospheric pressure in said
pressure chamber of roughly 20 bar and a relatively small
difference between said pressure in said pressure chamber and the
pressure in said suction box when said suction box is connected
to the underside of said filter belt.
Appeal No. 1997-3267
Application 08/324,386
means for supplying a mixture of liquid and solid
material to a first side of said filter belt;
means for connecting said suction box to an underside
of said filter belt; and
means for maintaining a higher than atmospheric
pressure in said pressure chamber of about 20 bar and a
relatively small difference of about 1-2 bar between the pressure
in said pressure chamber and the pressure in said suction box
when said suction box is connected to an underside of said filter
belt.