Honeywell International Inc.

Patent Trials and Appeals Board

Dec 18, 2020

2020000528 (P.T.A.B. Dec. 18, 2020)

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.
15/458,737 03/14/2017 Andrew J. Milley H0046758-1326.1389101 1052
90545 7590 12/18/2020
HONEYWELL/STW
Intellectual Property Services Group
300 S. Tryon Street
Suite 600
Charlotte, NC 28202
EXAMINER
PATEL, HARSHAD R
ART UNIT PAPER NUMBER
2855
NOTIFICATION DATE DELIVERY MODE
12/18/2020 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):
Honeywell.USPTO@STWiplaw.com
patentservices-us@honeywell.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ANDREW J. MILLEY and LAMAR FLOYD RICKS
Appeal 2020-000528
Application 15/458,737
Technology Center 2800
Before TERRY J. OWENS, JAMES C. HOUSEL, and
MERRELL C. CASHION, JR., Administrative Patent Judges.
HOUSEL, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 16–19, 22–27, and 29–35. We have
jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real party in interest as Honeywell
International Inc. Appeal Brief (“Appeal Br.”) filed July 23, 2019, 3.
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Application 15/458,737

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CLAIMED SUBJECT MATTER
The invention relates to flow sensors configured for sensing the flow
of a fluid in a flow channel. Specification (“Spec.”) filed March 14, 2017,
1:4–5.2
Claim 16, reproduced below from the Claims Appendix of the Appeal
Brief, is illustrative of the claimed subject matter:
16. A flow sensor for sensing a fluid flow rate through a flow
channel, the flow sensor comprising:
an upstream resistive element having a first resistance
that changes with temperature;
a downstream resistive element having a second
resistance that changes with temperature, wherein the
downstream resistive element is situated downstream of the
upstream resistive element in the flow channel;
the upstream resistive element and the downstream
resistive element are operatively connected in a bridge circuit,
wherein the bridge circuit is configured to supply a current to
each of the upstream resistive element and the downstream
resistive element, wherein the current causes resistive heating in
both the upstream resistive element and the downstream
resistive element such that both the upstream resistive element
and the downstream resistive element are heated above the
ambient temperature of the fluid flowing through the flow
channel, wherein fluid flow through the flow channel causing
the temperature of the upstream resistive element to be lower
than the temperature of the downstream resistive element;
a resistor connected in series with the bridge circuit;

2 This Decision also cites to the Final Office Action (“Final Act.”) dated
January 25, 2019 and the Examiner’s Answer (“Ans.”) dated August 30,
2019.
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Application 15/458,737

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a slit including a first side and a second side opposite to
the first side, wherein the slit extends transversely through the
flow sensor, wherein the upstream resistive element is
positioned adjacent the first side of the slit with no intervening
heater element positioned between the upstream resistive
element and the first side of the slit, and the downstream
resistive element is positioned adjacent the second side of the
slit with no intervening heater element positioned between the
downstream resistive element and the second side of the slit;
and
wherein a difference in temperature between the
upstream resistive element and the downstream resistive
element causes an imbalance in the bridge circuit that is related
to the fluid flow rate of the fluid flowing though the flow
channel.
Independent claims 22 and 27 also recite flow sensors.
REFERENCES
The Examiner relies on the following prior art:
Name Reference Date
Higashi et al.
(“Honeywell”)3
US 4,501,144 Feb. 26, 1985
Higashi US 4,696,188 Sept. 29, 1987
Appellant Admitted Prior
Art (“AAPA”)4
Spec. 3:15–5:12;
Figs. 2 and 3

3 The Examiner refers to this patent using the name of its assignee,
Honeywell Inc., apparently to distinguish this patent from the other patent
relied on, Higashi. Appellant does the same. We, likewise, adopt this
convention in order to avoid confusion.
4 Appellant does not dispute the prior art status, or the scope, of the
disclosure on which the Examiner relies as admitted prior art.
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Application 15/458,737

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REJECTIONS
The Examiner maintains, and Appellant requests our review of, the
following rejections:
1. Claims 16–19, 27, and 29–35 under 35 U.S.C. § 103 as
unpatentable over AAPA in view of Higashi; and
2. Claims 22–26 under 35 U.S.C. § 103 as unpatentable over
AAPA in view of Higashi, and further in view of
Honeywell.
OPINION
We review the appealed rejections for error based upon the issues
Appellant identifies, and in light of the arguments and evidence produced
thereon. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010) (precedential)
(cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011)
(“[I]t has long been the Board’s practice to require an applicant to identify
the alleged error in the examiner’s rejections.”)). After considering the
argued claims and each of Appellant’s arguments, we are not persuaded of
reversible error in the Examiner’s obviousness rejections. Therefore, we
affirm the stated rejections for substantially the fact findings, reasoning, and
conclusion of obviousness set forth in the Final Office Action and the
Examiner’s Answer, which we adopt as our own. We offer the following for
emphasis only.
For purposes of this appeal, to the extent that the rejected claims are
separately argued, we will address them separately consistent with 37 C.F.R.
§ 41.37(c)(1)(iv) (2018).
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Rejection 1: Obviousness over AAPA in view of Higashi
The Examiner rejects claims 16–19, 27, and 29–35 under 35 U.S.C.
§ 103 as unpatentable over AAPA in view of Higashi. A complete statement
of this rejection is set forth in the Final Office Action, pages 2–6.
The Examiner finds that AAPA teaches a flow sensor substantially as
recited in claim 16, except for the omission of an intervening heater element
positioned between upstream resistive elements RU1, RU2 and slit 310, as
well as between downstream resistive elements RD1, RD2 and slit 310,
wherein the resistive elements function both to heat and sense (current
supplied to the resistive elements causes resistive heating). Final Act. 2–3.
The Examiner finds that Higashi teaches upstream and downstream resistive
elements 16 that function both to heat and sense (current supplied to these
elements causes them to heat) such that no intervening heater element is
positioned between these resistive elements and slit 152. Id. at 3. The
Examiner concludes that it would have been obvious to adopt Higashi’s self-
heated resistive element teaching for the AAPA structure in order to reduce
the flow sensor’s size and cost of manufacturing. Id. at 4.
Appellant argues that neither the AAPA nor Higashi teaches or
suggests the flow sensor of claim 16. Appeal Br. 9–10. Appellant contends
that the AAPA discloses the use of a separate heater control circuit to control
current to the heater, and does not disclose a bridge circuit that supplies
current to the upstream and downstream resistive elements to cause them to
heat above ambient temperature. Id. at 10–11. Appellant further contends
that Higashi does not disclose a bridge circuit that supplies current to the
upstream and downstream resistive elements to cause them to heat above
ambient temperature. Id. at 11. Appellant asserts that Higashi instead
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discloses a completely different type of circuit including amplifiers for
supplying current to the resistive elements, wherein the difference between
the output of these amplifiers is amplified to produce an output that bears a
relationship with the gas flow rate. Id. Finally, Appellant urges that the
AAPA and Higashi teach away from a bridge circuit that supplies current to
the resistive elements for both heating and detecting a measure of fluid flow
rate via an imbalance in the bridge circuit. Id. at 11–12.
Appellant’s arguments are not persuasive primarily because Appellant
fails to address the combined teachings of the AAPA and Higashi, but rather
addresses each individual teaching separately. “Non-obviousness cannot be
established by attacking references individually where the rejection is based
upon the teachings of a combination of references. . . . [The reference] must
be read, not in isolation, but for what it fairly teaches in combination with
the prior art as a whole.” In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir.
1986). There is no dispute that the AAPA teaches a bridge circuit including
all of the elements recited in claim 16, except that the AAPA includes
separate circuitry for heating a heating resistor disposed between the
resistive elements and the slit. Nor is there any dispute that Higashi teaches a
flow sensor having upstream and downstream resistive elements that
function both for heating and flow rate detection, thereby omitting a separate
circuitry for heating a heating resistor disposed between the resistive
elements and a slit. The Examiner’s proposed combination modifies the
AAPA by omitting the separate heating circuitry and heating resistor and
utilizes the AAPA’s bridge circuit to supply current to the upstream and
downstream resistive elements to both heat and detect fluid flow in light of
Higashi’s teaching. In re Keller, 642 F.2d 413, 425 (CCPA 1981) (“The test
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for obviousness is not whether the features of a secondary reference may be
bodily incorporated into the structure of the primary reference. . . . Rather,
the test is what the combined teachings of the references would have
suggested to those of ordinary skill in the art.”). Appellant has neither
argued nor shown that such a modification would have been outside the
ordinary skill in the art or would have produced an unexpected result.
In addition, although Appellant alleges that the AAPA and Higashi
teach away from a bridge circuit that supplies current to the resistive
elements for both heating and detecting a measure of fluid flow rate via an
imbalance in the bridge circuit, the record fails to support Appellant’s
allegation. In this regard, Appellant fails to direct our attention to any
disclosure in either the AAPA or Higashi that criticizes, discredits, otherwise
discourages investigation into the claimed invention, or show that their
combined teachings would produce a seemingly inoperative device. “A
reference does not teach away, however, if it merely expresses a general
preference for an alternative invention but does not ‘criticize, discredit, or
otherwise discourage’ investigation into the invention claimed.” DePuy
Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567 F.3d 1314, 1327 (Fed.
Cir. 2009) (citing In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir. 2004)).
Appellant does not separately argue claims 17–19, 27, and 29–35. In
accordance with 37 C.F.R. § 41.37(c)(1)(iv) (2018), these claims stand or
fall with claim 16. Accordingly, we sustain the Examiner’s rejection of
claims 16–19, 27, and 29–35 under 35 U.S.C. § 103 as unpatentable over
AAPA in view of Higashi.

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Rejection 2: Obviousness over AAPA in view of Higashi and Honeywell
The Examiner rejects claims 22–26 under 35 U.S.C. § 103 as
unpatentable over AAPA in view of Higashi, and further in view of
Honeywell. A complete statement of this rejection is set forth in the Final
Office Action, pages 6–9.
The Examiner finds that AAPA, as modified in view of Higashi as
discussed above, teaches a flow sensor substantially as recited in claim 22,
except for a teaching that the resistance of the upstream resistive elements is
within 20 percent or less of the resistance of the downstream resistive
elements. Final Act. 6–7. However, the Examiner finds that Honeywell
teaches, regarding flow sensors, the resistive sensor elements that are
matched such that their resistances can be manufactured to within 0.1
percent. Id. at 8. Therefore, the Examiner concludes that it would have been
obvious that the resistances of the resistive sensor elements of the AAPA
flow sensor be within 0.1 percent in order to achieve matching. Id.
Appellant argues that Honeywell fails to teach or otherwise support
the Examiner’s finding that the resistances of the flow sensor resistive
elements can be matched to within 0.1 percent. Appeal Br. 15–16. However,
as aptly noted by the Examiner (Ans. 5), Appellant directs attention to the
wrong portion of Honeywell. The Examiner relies on Honeywell, column
18, lines 1–12; Appellant instead cites to column 8, lines 1–12. Column 18
of Honeywell clearly supports the Examiner’s finding. Honeywell 18:8–11
(“in processing, it is desirable to obtain a match between the upstream and
downstream sensor elements to a precision of about 0.1 percent”).
Appellant does not separately argue claims 23–26. In accordance
with 37 C.F.R. § 41.37(c)(1)(iv) (2018), these claims stand or fall with claim
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22. Accordingly, we sustain the Examiner’s rejection of claims 22–26 under
35 U.S.C. § 103 as unpatentable over AAPA in view of Higashi, and further
in view of Honeywell.
CONCLUSION
Upon consideration of the record and for the reasons set forth above
and in the Final Office Action and the Examiner’s Answer, the Examiner’s
decision to reject claims 16–19, 22–27, and 29–35 under 35 U.S.C. § 103 is
affirmed.
DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
16–19, 27,
29–35
103 AAPA, Higashi 16–19, 27,
29–35

22–26 103 AAPA, Higashi,
Honeywell
22–26
Overall
Outcome
16–19, 22–
27, 29–35

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