Ex Parte Nguyen

Board of Patent Appeals and Interferences

Apr 20, 2009

10328224 (B.P.A.I. Apr. 20, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte NICK NGOC NGUYEN
__________

Appeal 2009-1685
Application 10/328,224
Technology Center 3700
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Decided:1 April 21, 2009
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Before ERIC GRIMES, LORA M. GREEN, and
RICHARD M. LEBOVITZ, Administrative Patent Judges.

GRIMES, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a method
of detecting proper flow through a channel in an endoscope during a

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).
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cleaning procedure. The Examiner has rejected the claims as obvious. We
have jurisdiction under 35 U.S.C. § 6(b). We affirm.
STATEMENT OF THE CASE
Claims 1-9 are pending and on appeal. Claim 1 is representative and
reads as follows:
Claim 1: A method during a cleaning procedure of detecting proper
flow through one or more channels in an endoscope, the method comprising
the steps of:
a) connecting a first supply line to at least one of the one or more
channels, the supply line being in fluid communication with a fluid supply
vessel;
b) flowing, for a time period, fluid from the fluid supply vessel
through the first supply line into the one of the one or more channels;
c) determining an amount of fluid which has been flowed through the
first supply line by determining a volume change of fluid in the fluid supply
vessel;
d) calculating a flow rate through the first supply line based upon the
amount of fluid which has been flowed through the first supply line and the
time period; and
e) comparing the flow rate through the first supply line to a
predetermined value and if it varies by more than a predetermined amount
from the predetermined value providing an indication of improper flow;
wherein the fluid supply vessel comprises a tank of known dimensions
and a level sensing mechanism and wherein the step of determining the
volume change of fluid in the fluid supply vessel comprises, with the level
sensing mechanism, sensing the level of fluid in the tank prior to the time
period and after the time period and calculating the volume change based
thereupon.

The claims stand rejected under 35 U.S.C. § 103(a) as follows:
• claims 1 and 4-9 in view of Pfeifer2 and Mariotti3; and

2 Pfeifer, US 5,738,824, Apr. 14, 1998
3 Mariotti, US 5,882,589, March 16, 1999
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• claims 2 and 3 in view of Pfeifer, Mariotti, and Walta.4
OBVIOUSNESS
Issue
The Examiner has rejected claims 1 and 4-9 under 35 U.S.C. § 103(a)
as being obvious in view of Pfeifer and Mariotti.
The Examiner finds that Pfeifer discloses an endoscope cleaning
method comprising steps a) through e) of claim 1 (Ans. 4) but does not use a
tank of known dimensions and a level sensing mechanism to calculate the
volume change in the fluid supply vessel (id. at 5).
The Examiner finds that Mariotti discloses a device for cleaning and
disinfecting an endoscope, with the device “having a plurality of sensors
located throughout the system to provide feedback to the CPU” and
discloses sensors that “include high and low level sensors 302 and 304
which monitor the level of disinfectant concentrate in the tank 144” (id.).
The Examiner concludes that it “would have been obvious to one skilled in
the art to include level sensors in the apparatus of Pfeifer in order to ensure
that the amount of detergent injected is always equal to the exact volumetric
difference between the high and low sensor levels” (id. at 5-6).
Appellant contends that the Examiner erred in finding that one of skill
in the art would have been motivated to combine the level sensors of
Mariotti with the device of Pfeifer because “Pfeifer uses the principle of
measuring the pressure drop, not the principle of measuring a volume to
determine flow through a channel” (App. Br. 4).

4 Walta, US 6,260,560 B1, Jul. 17, 2001
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The issue with respect to this rejection is: Does the evidence of record
support the Examiner’s conclusion that one of skill in the art would have
been motivated to use the Mariotti level sensors to determine volume change
in Pfeifer’s fluid supply vessel?
Findings of Fact
1. Pfeifer discloses a “method for the testing and cleaning of
instruments for minimal invasive surgery or minimal invasive examination
of body cavities,” including endoscopes (Pfeifer, col. 1, ll. 8-10, 36-38).
2. Pfeifer describes its testing method as follows:
(a) the channel of the or each instrument is connected to a fluid
source; (b) the channel is tested for penetrability; (c) if there is
too little or no throughflow, the instrument in question is
recognized as being one that cannot be adequately flushed and
is registered for rejection, and (d) if the throughflow is
sufficient, the instrument in question is recognized as being one
that can be flushed and it is re-flushed with disinfecting and/or
cleaning agents.
(Id. at col. 3, ll. 9-19.)
3. Pfeifer discloses that “the channel is tested for penetrability by
means of fluid being delivered to it from the fluid source, a quantity of the
fluid flowing through the channel in one unit of time being determined, and
the fluid volume determined being compared with preset data specific to the
device” (id. at col. 3, ll. 19-24).
4. Pfeifer discloses that, “[i]n a preferred embodiment … , the
throughput rate is determined at the outlet side, … after flowing through the
channels. … [I]t is also possible, however, for the fluid quantity flowing
through a channel to be determined at the inlet side.” (Id. at col. 3, ll. 59-
64.)
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5. Pfeifer discloses that,
[i]n an alternative embodiment of the invention, the at least one
channel of one or more instruments is tested for penetrability by
means of this channel being subjected to pressure by delivery of
fluid from a pressurized fluid source, the pressure drop over
time as a result of a flow of fluid through the channel being
measured, and the determined pressure drop being compared
with preset data specific to the device.
(Id. at col. 3, ll. 65-col. 4, l. 5.)
6. Mariotti discloses an endoscope cleaning device “into which the
endoscope may be completely immersed. It is equipped with injectors
arranged so as to create a rotating flow of cleaning liquid and sterile rinsing
water or recycled drying air within the basin.” (Mariotti, col. 2, ll. 57-64.)
7. Mariotti discloses that a
plurality of sensors located throughout the system provide
feedback to the CPU, so as to enable it to control the overall
operation of the device and various components thereof.
Referring to FIG. 6, the sensors include: high and low level
sensors 302, 304 respectively, which monitor the level of
disinfectant concentrate in tank 166.
(Id. at col. 6, ll. 15-20.)
8. Mariotti discloses that the amount of disinfectant concentrate
added is
precisely measured in tank 166. High level sensor 302 is used
to limit filling disinfectant tank 166. Subsequently, a signal
from low level sensor [304] causes CPU 300 to deactivate
pump 170 when the level of disinfectant in tank 166 reaches
low level sensor 304. In this manner, the amount of detergent
[sic, disinfectant] injected is always equal to the exact
volumetric difference between the high and low sensor levels.
(Id. at col. 8, ll. 52-62.)
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Principles of Law
“The combination of familiar elements according to known methods
is likely to be obvious when it does no more than yield predictable results.”
KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, __, 127 S.Ct. 1727, 1739
(2007). “[W]hen the question is whether a patent claiming the combination
of elements of prior art is obvious,” the answer depends on “whether the
improvement is more than the predictable use of prior art elements according
to their established functions.” Id. at __, 127 S. Ct. at 1740.
The obviousness analysis “can take account of the inferences and
creative steps that a person of ordinary skill in the art would employ.” Id. at
__, 127 S. Ct. at 1741.
Analysis
Claim 1 is directed to a method of detecting proper flow through a
channel in an endoscope. The Examiner finds, and Appellant does not
dispute, that Pfeifer teaches the steps a) through e) recited in claim 1. Claim
1 also requires that the “fluid supply vessel comprises a tank … and a level
sensing mechanism” and that “the step of determining the volume change …
comprises, with the level sensing mechanism, sensing the level of fluid in
the tank prior to the time period and after the time period and calculating the
volume change.”
Pfeifer discloses that the rate of flow through an instrument can be
determined at the outlet side or at the inlet side, or in “an alternative
embodiment” can be measured based on pressure drop over time in a
pressurized fluid source. Pfeifer does not disclose using a fluid supply
vessel tank containing a level sensing mechanism or that “the step of
determining the volume change … comprises, with the level sensing
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mechanism, sensing the level of fluid in the tank” prior to and after the time
period for fluid flow.
Mariotti discloses a tank having high and low level sensors that detect
the amount of disinfectant concentrate added during an endoscope cleaning
procedure. That is, Mariotti teaches that an alternative method of measuring
the volume of fluid that has been injected is to use a tank of known
dimensions and a level-sensing mechanism. In view of these disclosures, it
would have been obvious to one of skill in the art to use the tank and fluid
level sensors of Mariotti in the Pfeifer method because one of skill in the art
would have appreciated that such sensors would be an alternative
mechanism to measure volume change in the tank and thus volume flow
through the channel being tested. Such a combination appears to be the
predictable use of prior art elements according to their established functions.
Appellant contends that the Examiner erred in finding that one of skill
would have been motivated to combine the level sensors of Mariotti with the
device of Pfeifer because “Pfeifer uses the principle of measuring the
pressure drop, not the principle of measuring a volume to determine flow
through a channel” (App. Br. 4).
This argument is not persuasive. As set forth above, Pfeifer
specifically discloses that the channel is tested for penetrability by means of
“a quantity of the fluid flowing through the channel in one unit of time,”
with the quantity of fluid being measured either at the outlet side or the inlet
side, and that an alternative embodiment is testing for a pressure drop after
pressurized fluid delivery. Thus, one of skill in the art would have
understood Pfeifer’s disclosure to mean that the quantity of fluid flowing
through the channel could be measured by any of a variety of methods,
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including a volume determination at the inlet side or the outlet side. Mariotti
teaches that one method of measuring the amount of fluid dispensed from a
tank (or, in other words, the amount of fluid flowing into the inlet of a
vessel) is to use a level-sensing mechanism to measure the volume of fluid
that has left a storage tank. A person of ordinary skill in the art would have
recognized that this principle would be equally applicable to Pfeifer’s
system.
With reference to claim 6,5 Appellant contends that the claim “defines
the level sensing mechanism comprising a reference connection at a lower
portion of the tank and a plurality of sensing electrodes there above. The
references are silent as to such arrangement.” (App. Br. 4.)
This argument is not persuasive. While Mariotti discloses only two
specific sensors in its level-sensing mechanism, “[i]n determining whether
obviousness is established by combining the teachings of the prior art, the
test is what the combined teachings of the references would have suggested
to those of ordinary skill in the art.” In re GPAC Inc., 57 F.3d 1573, 1581
(Fed. Cir. 1995) (internal quotations omitted).
Here, Pfeifer’s system requires injecting, and measuring, variable
amounts of fluid through an endoscope channel. Therefore, it would have
been obvious to a skilled artisan – in view of the teachings of the combined

5 Claim 6 reads: “[A method according to claim 1 wherein the level sensing
mechanism comprises a plurality of sensors vertically arrayed within the
tank] wherein the level sensing mechanism comprises a reference connection
at a lower portion of the tank and [a] plurality of sensing electrodes
thereabove and the method of sensing the level of fluid in the tank comprises
sensing electric current flow from the reference connection through the fluid
in the tank to the highest electrode to receive such current flow.”
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references – to include a plurality of sensors (sensing electrodes) at higher
levels than a low-level sensor (reference electrode), in order to measure
different quantities of fluid dispensed from the storage tank. Such a sensor
arrangement appears to be, in accord with KSR Int’l Co. v. Teleflex Inc., well
within the realm of the inferences and creative steps that one of skill in the
art would employ.
The Examiner has rejected claims 2 and 3 under 35 U.S.C. § 103(a) as
being obvious in view of Pfeifer, Mariotti, and Walta. Claim 3 has not been
argued separately and therefore stands or falls with claim 2.6 37 C.F.R.
§ 41.37(c)(1)(vii).
The Examiner relies on Pfeifer and Mariotti as discussed above, and
finds that Walta discloses the additional limitations of claim 2 (Ans. 6-7).
The Examiner concludes that it “would have been obvious to one skilled in
the art … to use the device and method of Walta in the apparatus of Pfeifer
and Mariotti … so that during cleaning and/or disinfecting of the endoscope
only single channels are present, and therefore the cleaning and the
disinfection system are more efficient and operationally reliable as taught by
Walta” (id. at 7).
We agree with the Examiner’s reasoning and conclusion.
Appellant does not dispute that Walta would have suggested the
limitation added to claim 1 by claim 2, but contends that Walta does not cure

6 Claim 2 reads: “A method according to claim 1 and further comprising the
steps of connecting a second supply line to a separate channel within the
endoscope, the second supply line being in fluid communication with the
fluid supply vessel, and repeating steps b) through e) for the second supply
line.”
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the deficiencies of the combination of Pfeifer and Mariotti in suggesting the
invention of claim 1 (App. Br. 4-5).
This argument is not persuasive because, for the reasons discussed
above, we conclude that the combination of Pfeifer and Mariotti would have
suggested the invention of claim 1.
CONCLUSIONS OF LAW
The evidence of record supports the Examiner’s conclusion that one
of skill in the art would have been motivated to use the Mariotti level
sensors to determine volume change in the fluid supply vessel in the Pfeifer
method.
SUMMARY
We affirm the rejection under 35 U.S.C. § 103(a) of claims 1 and 6 as
being obvious in view of Pfeifer and Mariotti. Claims 4, 5, and 7-9 fall with
claim 1. 37 C.F.R. § 41.37(c)(1)(vii). We affirm the rejection of claims 2
and 3 as being obvious in view of Pfeifer, Mariotti, and Walta.
TIME PERIOD FOR RESPONSE
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

LP
Appeal 2009-1685
Application 10/328,224

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