3M INNOVATIVE PROPERTIES COMPANY

Patent Trials and Appeals Board

Dec 24, 2021

2021002934 (P.T.A.B. Dec. 24, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/740,134 12/27/2017 Desmon T. Curran 75997US012 6791
32692 7590 12/24/2021
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL, MN 55133-3427
EXAMINER
GABRIEL, SAVANNAH L
ART UNIT PAPER NUMBER
3785
NOTIFICATION DATE DELIVERY MODE
12/24/2021 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):
LegalUSDocketing@mmm.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte DESMON T. CURRAN, JOHN A. DUFF,
BENJAMIN H. COOPER, JASON A. GRAVES, and
REYAD A. ABDULQADER
Appeal 2021-002934
Application 15/740,134
Technology Center 3700
Before JOHN C. KERINS, BENJAMIN D. M. WOOD, and
CARL M. DEFRANCO, Administrative Patent Judges.
WOOD, Administrative Patent Judge.

DECISION ON APPEAL
STATEMENT OF THE CASE

Pursuant to 35 U.S.C. § 134(a), Appellant appeals from the
Examiner’s decision to reject claims 1–18.1 We have jurisdiction under
35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word “Appellant” to refer to the applicant as defined in 37
C.F.R. § 1.42(a). Appellant identifies the real party in interest as 3M
Company. Appeal Br. 3.
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CLAIMED SUBJECT MATTER
The claims are directed to an exhaust apparatus for a personal
protection respiratory device. Spec. 1:5–6. Sole independent claim 1,
reproduced below, is illustrative of the claimed subject matter:
1. An exhaust apparatus for connection to a personal protection
respiratory device that defines a filtered air volume adjacent to
the face of a wearer and comprises at least one exhalation valve,
the apparatus comprising:
a blower in fluid connection with the at least one exhalation
valve, the blower being responsive to the wearer's respiratory
cycle to draw a substantial portion of the wearer's exhaled
breath through the at least one exhalation valve,
wherein, in response to the wearer's respiratory cycle, the
blower operates throughout the wearer's exhale breath, or a
substantial period thereof, and does not operate throughout the
wearer's inhale breath, or a substantial period thereof.
REFERENCES
Name Reference Date
Gosweiler US 2005/0103343 A1 May 19, 2005
Godfrey WO 2014/035641 A2 Mar. 6, 2014
REJECTION
Claims Rejected 35 U.S.C. § References
1–18 103 Godfrey, Gosweiler
OPINION
Appellant treats claim 1 as representative of claims 1–9 and 12–18,
and argues claims 10 and 11 separately. Appeal Br. 7–11. Accordingly, we
decide the appeal of the rejection of claims 1–9 and 12–18 on the basis of
claim 1 alone. 37 C.F.R. § 41.37(c)(1)(iv). Claims 10 and 11 will be
addressed separately.
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Claim 1
The Examiner finds that Godfrey teaches the claimed exhaust
apparatus, including a blower able to draw a substantial portion of the
wearer’s exhaled breath through the at least one exhalation valve. Final
Act. 3 (citing Godfrey 6:9–18, 7:22–25, Figs. 1–4); see id. at 10 (“Godfrey is
intended to provide a respirator that actively draws the user’s exhaled breath
from the mask in order [to] get rid of uncomfortable build-up of heat and
moisture.”). The Examiner acknowledges, however, that Godfrey does not
teach operating the blower throughout the wearer’s exhale breath, or a
substantial period thereof, and not operating the blower throughout the
wearer’s inhale breath, or a substantial period thereof. Id. at 3. The
Examiner finds that Gosweiler teaches an analogous respirator blower that is
responsive to the wearer’s respiratory cycle, in that it operates throughout
the wearer’s inhale breath, or a substantial period thereof, and does not
operate throughout the wearer’s exhale breath, or a substantial period
thereof. Id. (citing Gosweiler ¶¶ 32); see id. at 10 (“Gosweiler is used to
teach a blower system that operates responsive to a user’s breath for the
purpose of providing an efficient blower system that enhances the user’s
ability to breathe and increases operational time by preserving battery life.”)
(citing Gosweiler ¶ 18). The Examiner determines that it would have been
obvious to one of ordinary skill in the art “to modify the exhalation blower
of Godfrey with the teachings of Gosweiler of a breath responsive flow
pattern, for the purpose of providing an efficient blower system that
enhances the user’s ability to breathe and increases operational time by
preserving battery life.” Id. at 4. In support of this determination, the
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Examiner finds that “Godfrey states numerous times that optimal battery life
is a consideration.” Id. at 10 (citing Godfrey 7:18–21, 32, 8:11–13).
Appellant’s primary argument is that “[n]either Godfrey nor
Gosweiler has been shown to teach, or suggest, a blower not operating
through a wearer’s inhale breath or a substantial period thereof.” Appeal
Br. 7 (emphasis omitted). Instead, Appellant asserts that “Gosweiler teaches
turning off or lowering the speed of the blower 3 during a user’s exhalation
and ‘[t]urn-on may occur during inhalation,’” which is “the opposite of the
claimed features,” and Godfrey teaches that “the wearer controls when the
blower turns on or off by activating [a] switching mechanism.” Id. at 7–8
(citing Gosweiler ¶¶25–26; Godfrey 6:14–17, 7:21–22). Appellant further
asserts that “Gosweiler explicitly teaches that positive pressure is maintained
at all times within the mask while being used,” and thus “requires operation
of the blower throughout inhalation to maintain positive pressure at all times
within the mask.” Id. at 8 (citing Gosweiler ¶¶ 25, 29). Appellant therefore
contends that “a combination of the asserted teachings would operate the
blower during at least inhalation and likely during exhalation as well, as
taught by Godfrey, with reduced speed to preserve battery power, as taught
by Gosweiler.” Id.
Appellant also argues that since both Godfrey and Gosweiler teach
operating throughout inhalation, “modifying either one to not operate
throughout inhalation would directly change, and undermine, the principle
operation of Godfrey’s and/or Gosweiler’s blowers.” Id. at 10. Finally,
Appellant argues that Godfrey’s and Gosweiler’s teachings “appear to be
incompatible,” because “Godfrey teaches that optimum results are obtained
when the exhaust apparatus creates a pressure inside the mask of zero, or
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below zero,” “but Gosweiler requires that a positive pressure is maintained
at all times within the mask while being used.” Id. at 11 (citing Godfrey
11:38–12:3) (emphasis omitted).
The Examiner responds that Appellant’s arguments “are based on a
piecemeal interpretation of the references, rather than the collective
teachings of the references.” Ans. 3. The Examiner contends that “Godfrey
teaches an exhaust apparatus, attachable to a mask, comprised of a blower
that operates to draw a portion of the wearer’s exhaled breath through an
exhalation valve,” and “Gosweiler is used to teach dynamically controlling a
blower during a breathing cycle in order to save battery life.” Id. at 4.
According to the Examiner, “Gosweiler teaches turning on the blower during
the portion of the breath cycle where it is serving its intended purpose and
turning off the blower during the portion of the breath cycle where it is not
needed,” such that “less power is required to operate the air blower and the
battery life of the device is prolonged for a greater length of time.” Id.
(citing Gosweiler ¶¶ 18, 25, 29). The Examiner submits that Godfrey’s
“blower need only operate during the exhalation portion of the breath to
perform its intended function and Gosweiler teaches that turning it off when
it is not needed prolongs battery life.” Id. at 4–5. The Examiner
characterizes Appellant’s arguments as “focusing on the function of
Gosweiler as a blower used during inhalation,” whereas the rejection is
based on Gosweiler modifying Godfrey’s blower, which “draws out a
wearer’s exhaled breath.” Id. at 5. Thus, “Gosweiler is only used to teach
controlling the exhalation blower of Godfrey in a way that prolongs the
operating time of the device.” Id. Similarly, the Examiner characterizes
Appellant’s principle-of-operation argument as directed to “the operation of
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Gosweiler” rather than the modification of Godfrey as modified by
Gosweiler; the Examiner submits that “the principle of operation of Godfrey
is to draw out exhaled breath[] and not operating the blower during the
inhalation breath[] would not change this function.” Id.
In the Reply Brief, Appellant counters that the Examiner ignores
Gosweiler’s express teaching that “positive pressure is maintained at all
times within the mask while being used,” which “requires operation of the
blower throughout inhalation.” Reply Br. 7 (citing Gosweiler ¶¶ 25, 29).
Appellant also submits that “Gosweiler’s mask also ‘helps the user to exhale
in the mask,’” suggesting that combining Godfrey with Gosweiler would
result in the blower operating during both inhalation and exhalation. Id. at 8
(citing Gosweiler ¶ 11).
We have carefully considered Appellant’s and the Examiner’s
arguments, and determine that the Examiner has the better position. The
record supports the Examiner’s finding that Godfrey’s exhaust apparatus is
intended to draw hot, humid exhaled breath that is otherwise trapped in the
cavity created between the respirator and the wearer’s face. See, e.g.,
Godfrey 2:1–2, 9–10, 4:36, 6:3–8, Fig. 4. One of ordinary skill in the art
would have reasonably inferred that Godfrey’s blower need only operate
during the exhalation portion of the breath cycle to perform its intended
purpose of removing exhaled breath. See Ans. 4–5 (Godfrey’s “blower need
only operate during the exhalation portion of the breath to perform its
intended function”). Godfrey also teaches that extending battery life should
be considered in operating the blower. Godfrey 7:32–34. One of ordinary
skill in the art, seeking to operate Godfrey’s blower to optimize both battery
life and cooling effect, would therefore have looked to Gosweiler, which
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teaches turning off the positive-pressure blower when it is not needed, i.e.,
during exhalation, to optimize battery life and make it easier for the wearer
to exhale. Gosweiler ¶¶ 5–6, 18. Since Godfrey’s blower need only operate
during the exhalation portion of a breath cycle, one of ordinary skill in the
art would have applied Gosweiler’s teaching to Godfrey’s blower to only
operate the blower during the exhalation and not during inhalation.
Appellant asserts that this analysis ignores Gosweiler’s teaching that
positive pressure must be maintained at all times within the mask, which
requires operation of the blower throughout inhalation. Appeal Br. 8. As
the Examiner notes, however, this argument is not responsive to the rejection
as articulated by the Examiner, which is based on modifying Godfrey’s
device rather than Gosweiler’s device, Gosweiler being relied on only for its
teaching to conserve battery life by operating a blower only when necessary.
Appellant’s argument implies that one of ordinary skill in the art would be
unable to apply this teaching without also following Gosweiler’s instruction
to maintain position pressure within the mask. We disagree. Gosweiler’s
invention relates to a “fan-forced positive pressure breathing apparatus,” in
which “[t]he fan or blowing element continuously supplies filtered air to the
gas mask.” Gosweiler ¶ 5 (emphasis added). Godfrey’s device, on the other
hand, is a powered exhaust apparatus for a negative pressure respirator, in
which negative pressure is created when the wearer draws a breath, thus
drawing in air through the filter system. Godfrey 1:12–15. One of ordinary
skill in the art, presumed familiar with both Godfrey and Gosweiler (and
thus the existence and operation of positive-pressure and negative-pressure
respirators), would likely appreciate that a teaching to maintain positive
pressure in a positive pressure breathing apparatus would not be applicable
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to a negative pressure breathing apparatus. To hold otherwise would
incorrectly presume that a person of ordinary skill in the art is
unknowledgeable and unskilled. In re Sovish, 769 F.2d 738, 743 (Fed. Cir.
1985); see KSR Int’l. Co. v. Teleflex Inc., 550 U.S. 398 421 (2007) (“A
person of ordinary skill is also a person of ordinary creativity, not an
automaton.”).
We are also not persuaded by Appellant’s argument that “modifying
either [Godfrey or Gosweiler] to not operate throughout inhalation would
directly change, and undermine, the principle [of] operation of Godfrey’s
and/or Gosweiler’s blowers.” Appeal Br. 10. Since Godfrey’s blower is
intended to remove exhaled breath from the mask, which only requires
operation during the exhalation part of the breath cycle, we are not
persuaded that operating during the inhalation part of the cycle constitutes
Godfrey’s principle of operation. Further, since the Examiner is not
proposing modifying Gosweiler’s apparatus, the principle of operation of
that apparatus is not relevant to the combination.
Appellant also argues that Godfrey’s and Gosweiler’s teachings
“appear to be incompatible as Godfrey teaches that optimum results are
obtained when the exhaust apparatus creates a pressure inside the mask of
zero, or below zero . . ., but Gosweiler requires that a positive pressure is
maintained at all times within the mask while being used.” Appeal Br. 11
(citing Godrey 11:38–12:3). Appellant asserts that “[m]odifying Gosweiler
to not operate the blower during inhalation would directly undermine these
teachings.” Id. Again, however, the rejection is not based on the
modification of Gosweiler, but of Godfrey. Ans. 5.
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Finally, as noted above, Appellant argues in the Reply Brief that
“Gosweiler’s mask also ‘helps the user to exhale in the mask,’” suggesting
that combining Godfrey with Gosweiler would result in the blower operating
during both inhalation and exhalation. Id. at 8 (citing Gosweiler ¶ 11). But
Gosweiler helps the user exhale in the mask by reducing positive air
pressure in the respirator mask during exhalation, which is accomplished by
turning off the blower, or reducing its speed. Gosweiler ¶ 29. Thus,
combining Godfrey and Gosweiler would not result in the continuous
operation of the blower.
Claims 10 and 11
Claims 10 depends indirectly from claim 1 via claims 2, 5, 6, and 7,
and additionally recites: (1) a controller (claim 2); (2) a pressure sensor for
sensing a pressure generated by the wearer’s breathing cycle and sending a
pressure signal indicative of the pressure to the controller (claim 2); (3) the
controller in communication with the pressure sensor and the blower (claim
2); (4) the controller operating the blower in response to the pressure signal
(claim 2); (5) the controller starting the blower when the pressure sensed by
the pressure sensor reaches a “first predetermined pressure” (claim 5);
(6) the controller stopping the blower when the pressure sensed by the
pressure sensor falls below a “second predetermined pressure” (claim 6);
(7) the first predetermined pressure and the second predetermined pressure
are a “common predetermined pressure” (claim 7); and (8) the common
predetermined pressure “is lower than ambient pressure so that the controller
starts the blower momentarily before the initiation of the wearer’s exhale
breath and stops the blower momentarily after the end of the wearer’s exhale
breath.” Appeal Br. 13–15 (Claims App.). Claim 11 depends indirectly
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from claim 1 via claims 2 and 5, and additionally recites “wherein the first
predetermined pressure is greater than the second predetermined pressure so
that the controller starts the blower momentarily after the initiation of the
wearer’s exhale breath and stops the blower momentarily after the end of the
wearer’s exhale breath.” Id.
The Examiner finds that “Godfrey teaches controlling the exhaust
apparatus based on environmental conditions and user preferences,” and
“Gosweiler teaches that various signals can be used to control the function
of the air blower”; and determines that it would have been obvious to one of
ordinary skill in the art “to vary the predetermined pressure to one that is
preferable to the user.” Final Act. 7 (citing Godfrey 7:22–24).
Appellant responds that Godfrey teaches turning the blower on or off
or adjusting the blower’s speed, and Gosweiler teaches “that positive
pressure is maintained at all times with the mask . . . such that the pressure in
Gosweiler’s mask would never be lower than ambient pressure,” but “[t]here
is no mention of starting or stopping the blower based on a pressure lower
than ambient.” Appeal Br. 9 (emphasis omitted). Appellant makes similar
arguments for claim 11. Id. at 9–10.
The Examiner counters that “[t]he modification of Godfrey with the
teachings of Gosweiler teach a blower that operates during an exhaled breath
and turns off during an inhaled breath”; and Gosweiler “teaches setting
predetermined pressure levels for the start and stop operation of the blower”;
thus, “it would be obvious to one skilled in the art to set the level to start the
blower around the user’s initiation of the exhaled breath and stop around the
user’s initiation of the inhaled breath.” Ans. 6. According to the Examiner,
“[s]tarting the blower momentarily before, right at, or momentarily after
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initiation of the wearer’s exhale breath are options well within the purview
of design choice.” Id.
A limitation may be found to be an obvious matter of design choice if,
e.g., it does not result in a difference in function or give unexpected results
(In re Rice, 341 F.2d 307, 314 (CCPA 1965)); if it solves no stated problem
(In re Kuhle, 529 F.2d 553, 555 (CCPA 1975)); or if it does not modify the
operation of the claimed device (In re Japikse, 181 F.2d 1019 (CCPA 1950).
Notably, Appellant does not dispute the Examiner’s characterization of the
additional limitations of claims 10 and 11 as “within the purview of design
choice.” Ans. 6. Nor do we discern anything in the record that would
suggest error in this characterization. Neither the claims nor the
Specification gives one the sense of how long “momentarily” before/after
exhalation would be encompassed by claims 10 and 11. The claims would
therefore encompass insubstantial differences between starting the blower
momentarily before exhalation started, immediately upon exhalation
starting, and momentarily after exhalation starting, and likewise, stopping
the blower momentarily before exhalation ends, immediately at the ending
of exhalation, or momentarily after exhalation ends. Thus, choosing
between these options would be unlikely to result in a difference in function
or give unexpected results.
Summary
Because we are not persuaded that the Examiner erred in rejecting
claims 1, 10, and 11, we sustain the Examiner’s rejection of claims 1–18 as
unpatentable over Godfrey and Gosweiler.
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DECISION SUMMARY
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1–18 103 Godfrey, Gosweiler 1–18

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). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED