Sathish Das et al.

Patent Trials and Appeals Board

Sep 24, 2021

2021001764 (P.T.A.B. Sep. 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.
13/822,817 03/13/2013 Sathish R. Das 54404US02 (U180002US2) 1708
87059 7590 09/24/2021
Cantor Colburn LLP - Carrier
20 Church Street, 22nd Floor
Hartford, CT 06103
EXAMINER
SHAIKH, MERAJ A
ART UNIT PAPER NUMBER
3763
NOTIFICATION DATE DELIVERY MODE
09/24/2021 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):
usptopatentmail@cantorcolburn.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte SATHISH R. DAS, ADEYEMI A. ADEPETU,
DON A. SCHUSTER, and RAJENDRA K. SHAH
Appeal 2021-001764
Application 13/822,817
Technology Center 3700
Before CHARLES N. GREENHUT, ANNETTE R. REIMERS, and
CARL M. DEFRANCO, Administrative Patent Judges.

DEFRANCO, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–3, 5–13, and 15–20. Claims 4 and 14
are canceled. We have jurisdiction under 35 U.S.C. § 6(b). We affirm.
CLAIMED SUBJECT MATTER
The claimed subject matter relates to a refrigerant vapor compression
system, and, more particularly, to “a system for stabilizing superheat based
on ambient temperature and compressor speed to provide enhanced

1 We use the term “Appellant” to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies Carrier Corporation as the real party in
interest. Appeal Br. 1.
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operation.” Spec. ¶ 2. Of the pending claims, claims 1 and 9 are
independent, with claim 1 being directed to a “refrigerant vapor compression
system” and claim 9 being directed to a “method of controlling” the system.
Claim 1, reproduced below, is illustrative:
1. A refrigerant vapor compression system comprising:
a compressor;
an expansion valve;
a compressor speed sensor operatively connected to the
compressor;
an evaporator outlet pressure sensor;
an ambient temperature sensor;
a controller operatively coupled to the expansion valve,
compressor speed sensor, evaporator outlet pressure sensor, and
ambient temperature sensor, the controller including a
superheat control configured to selectively activate the
expansion valve to establish a desired superheat value based on
evaporator outlet pressure, a speed of the compressor as sensed
by the compressor speed sensor, and ambient temperature as
sensed by the ambient temperature sensor; and
wherein the controller includes a transient operation
control that, upon detecting a transient system change,
establishes a predicted expansion valve position based on the
sensed transient system change, waits for a waiting period,
determines if the refrigerant vapor compression system has
achieved stable operation, resets the predicted expansion valve
position when the refrigerant vapor compression system has not
achieved stable operation and reverts to the superheat control
when the refrigerant vapor compression system has achieved
stable operation.
Appeal Br. 11 (Claims App.) (emphases added).
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REJECTIONS ON APPEAL
1. Claims 15–17 stand rejected under 35 U.S.C. § 112, second
paragraph, as being indefinite. Final Act. 2.
2. Claims 1, 3, 5, 8, 9–11, and 15–17 stand rejected under 35 U.S.C.
§ 103(a) as being unpatentable over Matsuoka (US 4,807,445; Feb. 28,
1989), Nonaka (JPH 10160273 A; June 19, 1998), and Doi (US
2005/0150240 A1; July 14, 2005). Final Act. 3–7.
3. Claim 2 stands rejected under § 103(a) as being unpatentable over
Matsuoka, Nonaka, Doi, and Lee (US 6,951,116 B2; Oct. 4, 2005). Final
Act. 8.
4. Claims 6 and 7 stand rejected under § 103(a) as being unpatentable
over Matsuoka, Nonaka, Doi, and Alsenz (US 4,651,535; Mar. 24, 1987).
Final Act. 8–9.
5. Claims 12 and 13 stand rejected under § 103(a) as being
unpatentable over Matsuoka, Nonaka, Doi, Lee, and Goto (JPH08200843A;
Aug. 6, 1996). Final Act. 9.
6. Claim 18 stands rejected under § 103(a) as being unpatentable over
Matsuoka, Nonaka, Doi, and Alsenz. Final Act. 9.
7. Claim 19 stands rejected under § 103(a) as being unpatentable over
Matsuoka, Nonaka, Doi, Alsenz, and Widdowson (US 3,715,894; Feb. 13,
1973). Final Act. 9.
8. Claim 20 stands rejected under § 103(a) as being unpatentable over
Matsuoka, Nonaka, Doi, Alsenz, and Ludwig (US 2006/0042282 A1;
Mar. 2, 2006). Final Act. 9.
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ANALYSIS
A. Indefiniteness
Appellant does not appeal the Examiner’s indefiniteness rejection of
claims 15–17 under 35 U.S.C. § 112, second paragraph. See Appeal Br. 3
n.1. Thus, we summarily sustain the Examiner’s indefiniteness rejection.
See In re Berger, 279 F.3d 975 (Fed. Cir. 2002) (upholding the Board’s
affirmance of an uncontested rejection because appellant had waived the
right to contest the rejection by not presenting arguments on appeal to the
Board).
B. Obviousness
1. Claims 1, 3, 5, 8, 9–11 and 15–17
We begin with claim 1. The Examiner finds that Matsuoka discloses
substantially all the elements of the refrigeration system as claimed,
including compressor 10, expansion valve 16, ambient temperature
sensor 30, and controller 22 operatively coupled to the expansion valve and
the temperature sensor. Final Act. 3 (citing Matsuoka, Abstract, Figs. 1, 14).
The Examiner further finds that Matsuoka’s controller includes the two
control modes as claimed, namely, “a superheat control” and “a transient
operation control.” Id. at 4–5 (citing Matsuoka, 8:25–35, 8:46–60, Fig. 3,
Fig. 11 (steps 314–316)). The Examiner acknowledges, however, that
Matsuoka omits the claim elements of “a compressor speed sensor” and “an
evaporator outlet pressure sensor” coupled to the controller for also
activating the expansion valve. Id. at 4–5.
For the first missing element, the Examiner finds that Nonaka teaches
a compressor speed sensor 9 operatively connected to a controller 10 for
activating an expansion valve 4. Id. at 4 (citing Nonaka, Abstract, ¶ 8,
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Fig. 1). According to the Examiner, Nonaka’s controller includes a
superheat control that establishes a desired superheat value (optimum SH
value) based on compressor speed N for controlling and readjusting the
expansion valve position “based on the temperature discharge adjustment
caused by a change in the compressor speed after the transient change in
compressor outlet enthalpy.” Id. (citing Nonaka, ¶¶ 11, 14, 22, 25, Fig. 4).
From there, the Examiner concludes that one skilled in the art would have
deemed it obvious to reconfigure the controller of Matsuoka so as to activate
the system’s expansion valve “based on the compressor speed as taught by
Nonaka in order to attain higher efficiency throughout various operations of
the refrigeration cycle as the efficiency of the compressor depends upon the
rotation speed of the compressor.” Id. at 4–5.
For the second missing element, the Examiner finds that Doi teaches
an evaporator outlet pressure sensor 159B coupled to a controller 171 for
activating an expansion valve. Id. at 5 (citing Doi, Abstract, ¶¶ 38, 45,
Fig. 2). Doi’s controller calculates a transient system change based on the
sensed data for the purpose of resetting the opening degree of the expansion
valve “to get a superheat value of at least 5 degree [Celsius].” Id. (citing Doi
¶¶ 45, 48–49, Figs. 3, 4). Based on those findings, the Examiner concludes
that it would have been obvious to one skilled in the art to modify the
expansion valve activation in Matsuoka’s system
to establish the superheat value based on evaporator outlet
pressure . . . as taught by Doi in order to control the degree of
superheat at the outlet of the evaporator to attain positive
superheat at the evaporator outlet and prevent liquid refrigerant
from entering the compressor and in order to allow the
expansion valve to achieve the desired position and allow the
refrigeration system to circulate the refrigerant at the desired
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expansion valve position before making a change for the
change in operational state of the system.

Id.
Appellant disputes only the Examiner’s finding that Matsuoka
discloses the two control modes required by claim 1, namely, “a superheat
control” and “a transient operation control.” Appeal Br. 4–7 (emphasis
omitted). Appellant does not dispute the Examiner’s findings and
conclusions with respect to Nonaka and Doi. Rather, according to
Appellant, the Examiner errs in finding that Matsuoka’s Figure 3 depicts a
transient operation control for “the period of time from [point] 0 to point c”
and a super heat control for “the period of time after point c.” Id. at 5.
Appellant argues that Figure 3 actually supports a different finding—that
Matsuoka uses “the same control process . . from time 0 onward” wherein
“only an integral variable, Ti, is altered to accommodate for the transient
superheat from point to point c,” regardless of “whether the system is
experiencing transient superheat or stable superheat.” Id. at 5–6 (quoting
and discussing Matsuoka, 8:22–45, Fig. 3). Or, as Appellant also puts it,
“Matsuoka discloses a single PID control mode with an integral variable, Ti,
that varies based on whether the superheat is transient or stable.” Id. at 7.
“Varying the integral variable, Ti,” Appellant asserts, “does not correspond
to the language of claim 1.” Id. at 6. According to Appellant, “reducing the
integral variable, Ti, does not correspond to the claimed ‘transient operation
control that, upon detecting a transient system change, establishes a
predicted expansion valve position based on the sensed transient system
change . . . .’” Id. at 7.
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We disagree. To begin, we note that Appellant does not dispute that
Matsuoka’s controller includes a “superheat control” mode as claimed. See
Appeal Br. 5–7. Instead, Appellant’s argument focuses on the claimed
“transient operation control,” which performs the following steps:
establishes a predicted expansion valve position based on the
sensed transient system change, waits for a waiting period,
determines if the . . . system has achieved stable operation,
resets the predicted expansion valve position when the . . .
system has not achieved stable operation[,] and reverts to the
superheat control when the . . . system has achieved stable
operation.

See id. at 6–7 (arguing that “[i]n Matsuoka, reducing the integral variable,
Ti, does not correspond to the claimed ‘transient operation control that
. . . .”).
Appellant does not apprise us of error in the Examiner’s finding that
Matsuoka’s controller employs a “superheat control” and a “transient
operation control” in the manner claimed. See Ans. 4. As noted by the
Examiner, Matsuoka’s Figure 3 discloses that the control circuit operates in
a superheat control mode once the system achieves a stable state (meaning
after point c) and operates in a transient operation control mode while
attempting to reach a stable state (meaning from point 0 to point c). See
Matsuoka, 8:22–45, 8:50–60. In other words, point c serves as a reference
point where Matsuoka’s controller changes from a transient control mode to
a superheat control mode in the process of controlling the degree of opening
of the expansion valve. Indeed, in describing that process, Matsuoka refers
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repeatedly to a “PID[2] control” that monitors the elapsed time after the start
of the system and “[w]hen the elapsed time reaches a reference time, a
control constant . . . of the PID control is changed from a first value to a
second value.” Matsuoka, 2:46–56 (emphasis added). According to
Matsuoka, “the elapsed time before a change of control constant is not
fixed,” but depends on the “number of times” that “the actual degree of
superheat alternately overshoots and undershoots a desired degree of
superheat” (also known as “crossings”). Id. at 2:57–3:3.
Those passages, in our view, support a dual mode operation where the
control constant has a start value during the unfixed period of time the
superheat overshoots and undershoots a desired objective (transient
superheat operation) before the control constant changes to a steady state
value upon the superheat reaching the desired objective (stable superheat
operation).
With regard to Appellant’s argument that “reducing the integral variable, Ti,
does not correspond to the claimed ‘transient operation control that, upon
detecting a transient system change, establishes a predicted expansion valve
position based on the sensed transient system change . . . .,’” it is noted that
Appellant does not adequately address the Examiner’s position in this
regard. The Examiner cited Figure 11, step 314, and variable Dtn as
meeting this limitation. Final Act. 3. As the Examiner additionally notes,
Matsuoka’s Figure 11 illustrates that the degree of opening the expansion

2 A PID control is defined as a process that “includes proportional, integral,
and derivative control components.” Matsuoka, 1:43–45; see also id. at
2:46–48 (“The degree of opening of the expansion valve is controlled by a
proportional plus integral plus derivative (PID) control.”).
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valve, referred to as “Dtn,” is determined on the basis of variations in the
value of Ti (which Appellant acknowledges varies depending on the
transient or stable state, i.e., before and after point c in Matsuoka Figure 3),
and also on the basis of variations in the value of other variables, such as Kp,
N, and Theta. See Ans. 4–6 (citing Matsuoka, Fig. 11, steps 301, 314-316);
see also Matsuoka, 7:25–44 (defining “optimum PID control constants” for
calculating Dtn as including Kp, Ti, and Td variables). Variations in the
values of those variables, the Examiner explains, indicate the use of
“different control methods” as supported by Matsuoka’s Figures 3 and 4,
which show “variations in the value of Ti from Tis to Tio after point c,”
whereas “Ti = Tis before point c.” Ans. 6; see also Matsuoka, 8:31–37
(describing same). Matsuoka’s Figure 5 similarly illustrates a variation in
Kp before and after point c. See Matsuoka, 8:41–44 (describing the
variations depicted in Fig. 5). Thus, the Examiner determines there were not
only “different control methods,” but additionally “control processes for
determining [the] degree of opening of the expansion valve (DTn) before
point c.” Ans. 6. Other than a naked assertion that Matsuoka lacks this
aspect of the claimed subject matter, Appellant provides no arguments as to
why this process in Matsuoka, as relied upon by the Examiner, is not
reasonably regarded as falling within the claim language, “upon detecting a
transient system change, establishes a predicted expansion valve position
based on the sensed transient system change.” The Examiner’s position in
this regard stands essentially uncontroverted for purposes of this appeal.
The remaining language of the claim quoted by Appellant, “waits for
a waiting period . . .” seems clearly met by the Examiner’s reference to the
waiting interval and looped operation depicted in Figure 11. Final Act. 3–4.
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Again, Appellant does not point out with specificity any supposed errors in
the Examiner’s determinations in these regards.
In the end, the Examiner provides sufficient evidentiary support and
explanation for finding that Matsuoka discloses the two control modes as
claimed. See Final Act. 3–4; Ans. 4–6. Moreover, the Examiner
persuasively rebuts Appellant’s argument that Matsuoka does not perform
transient operation control in the claimed manner. See Ans. 6. Appellant
provides no rebuttal to the contrary. Without more from Appellant, we are
not apprised of error in the Examiner’s findings with respect to Matsuoka’s
two control modes for activating the expansion valve, and because Appellant
does not further dispute the Examiner’s findings and conclusions with
respect to the combined teachings of Matsuoka, Nonaka, and Doi, we sustain
the obviousness rejection of claim 1. We also sustain the rejection of
dependent claims 3, 5, and 8, which are not argued separately and thus fall
with claim 1. See 37 C.F.R. § 41.37(c)(1)(iv).
Acknowledging the “similarities of claim 9 to claim 1,” Appellant
relies on “the arguments advanced with respect to claim 1” while noting that
“neither Nonaka nor Doi cures the deficiencies of Matsuoka.” Appeal
Br. 7–8. As discussed above, we reject the notion that the Examiner’s
proposed combination of Matsuoka, Nonaka, and Doi is deficient in
satisfying the two control modes of claim 1. Thus, for the same reasons we
sustain the rejection of claim 1, we likewise sustain the rejection of claim 9,
as well as dependent claims 10, 11, and 15–17, which are not argued
separately and fall with claim 9.
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2. The Remaining Claims
Appellant addresses dependent claims 2, 6, 7, 12, 13, and 18–20
separately from their respective independent claims 1 and 9. See Appeal Br.
8–9. But, in contesting the rejections of claims 2, 6, and 7, Appellant states
simply that those rejections “should be reversed for at least the reasons
advanced with respect to claim 1.” Id. at 8–9. Likewise, in contesting the
rejections of claims 12, 13, and 18–20, Appellant states simply that those
rejections “should be reversed for at least the reasons advanced with respect
to claim 9.” Id. at 9. As discussed above, we are not persuaded by the
arguments advanced by Appellant with respect to either claim 1 or claim 9.
Thus, we likewise sustain the Examiner’s obviousness rejections of
dependent claims 2, 6, 7, 12, 13, and 18–20.
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CONCLUSION
Claims
Rejected
35
U.S.C. §
Reference(s)/Basis Affirmed Reversed
15–17 112 Indefinite 15–17
1, 3, 5, 8,
9–11, 15–17
103(a) Matsuoka, Nonaka,
Doi
1, 3, 5, 8,
9–11, 15–17

2 103(a) Matsuoka, Nonaka,
Doi, Lee
2
6, 7 103(a) Matsuoka, Nonaka,
Doi, Alsenz
6, 7
12, 13 103(a) Matsuoka, Nonaka,
Doi, Lee, Goto
12, 13
18 103(a) Matsuoka, Nonaka,
Doi, Alsenz
18
19 103(a) Matsuoka, Nonaka,
Doi, Alsenz,
Widdowson
19
20 103(a) Matsuoka, Nonaka,
Doi, Alsenz,
Ludwig
20
Overall
Outcome
1–3, 5–13,
15–20

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)(1)(iv).
AFFIRMED