Ex Parte Hahn

Patent Trial and Appeal Board

Jul 28, 2016

12203164 (P.T.A.B. Jul. 28, 2016)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/203,164 09/03/2008
26096 7590 08/01/2016
CARLSON, GASKEY & OLDS, P.C.
400 WEST MAPLE ROAD
SUITE 350
BIRMINGHAM, MI 48009
FIRST NAMED INVENTOR
Gregory W. Hahn
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
60298-613; ST 347 2661
EXAMINER
GONZALEZ, PAOLO
ART UNIT PAPER NUMBER
3744
NOTIFICATION DATE DELIVERY MODE
08/01/2016 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):
ptodocket@cgolaw.com
cgolaw@yahoo.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte GREGORY W. HAHN
Appeal2014-006272
Application 12/203, 164
Technology Center 3700
Before GEORGE R. HOSKINS, AMANDA F. WIEKER, and
FREDERICK C. LANEY, Administrative Patent Judges.
HOSKINS, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Gregory W. Hahn ("Appellant") 1 appeals under 35 U.S.C. § 134 from
the Examiner's decision rejecting, under 35 U.S.C. § 103(a), claims 1, 2,
4---6, 8-10, 12-15, and 17-19 as unpatentable over Christensen (US 2008/
0134701 Al, pub. June 12, 2008), Lifson (WO 2006/132638 Al, pub.
Dec. 14, 2006), and He (US 2005/0103035 Al, pub. May 19, 2005). 2 The
Board has jurisdiction over the appeal under 35 U.S.C. § 6(b).
We REVERSE.
1 The Appeal Brief identifies Danfoss Scroll Technologies, LLC as the real
party in interest. Appeal Br. 1.
2 The Examiner has withdrawn the rejections of claims 7, 11, 16, and
20-25. Ans. 2. Thus, there is no rejection of these claims for us to review.
Appeal2014-006272
Application 12/203,164
CLAIMED SUBJECT MATTER
Claims 1, 8, and 13 are independent. Claim 1 illustrates the subject
matter on appeal, and it recites:
1. A compressor comprising:
a motor for a compressor pump unit, and said compressor
pump unit and said motor being housed within a shell, said shell
having a sump for maintaining a quantity of lubricant;
a control for said compressor, said control being
programmed to operate the motor in at least one low capacity and
at least one higher capacity, said control also being operable to
estimate a quantity of oil which will have migrated from said
compressor shell at least when said compressor is operating at
said at least one lower capacity, the estimated quantity of oil
calculated over time based upon a condition measured at both a
condenser and an evaporator, and said control being operable to
move said compressor motor from the at least one lower capacity
to the at least one higher capacity once the estimated quantity of
oil exceeds a predetermined limit.
Appeal Br. 15 (Claims App.).
ANALYSIS
In rejecting claim 1 as obvious over Christensen, Lifson, and He, the
Examiner finds Christensen discloses much of the claimed subject matter,
including "control (82, 92)" to operate a compressor motor, based on an
estimated quantity of oil migrated from the compressor. Final Act. 2-3.
The Examiner further finds Christensen does not disclose, as claimed: (a) the
motor driving a compressor pump, with the motor and compressor pump
housed within a shell having a sump for maintaining a lubricant, or (b) the
estimated quantity of oil being based on a condition measured at both a
condenser and an evaporator. Id. at 3, 4. The Examiner relies on Lifson in
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Appeal2014-006272
Application 12/203,164
relation to subject matter (a). Id. at 3--4. Appellant does not challenge that
part of the rejection, so we need not further address subject matter (a) or
Lifson.
As to subject matter (b ), the Examiner finds He discloses controller 10
"for estimating [a] quantity of oil calculated over time in a refrigerant
system, ... based upon the pressures I temperatures at both a condenser and
an evaporator." Final Act. 5 (citing He, Figs. lA-lB, 2, 3, and 17-19,
Abstract, i-fi-18, 39, 44--46, 103, 163-166, and 182). The Examiner
determines it would have been obvious to modify Christensen's control "to
estimate the amount of oil as claimed in view of the teachings of He so as to
improve the control system by accurately estimat[ing the] quantity of oil in
the compressor and assure reliable lubrication to the compressor ... to
improve the reliability of the system/compressor." Id. at 6.
Appellant argues "there is no reason to modify Christensen in view of
He." Appeal Br. 5; Reply Br. 3. Appellant contends the Examiner
"provides no evidence that Christensen's approach is any less reliable than"
He's approach, so the Examiner's rationale for the combination-to improve
the reliability of Christensen's system-lacks a rational basis. Appeal Br. 5-
6. Appellant moreover asserts He's oil model includes estimation error,
which may overestimate3 the amount of oil in Christensen's compressor, and
therefore fail to increase compressor speed when appropriate, whereas there
is no evidence that Christensen fails to increase compressor speed when
necessary. Id. (citing He i-fi-f 174--175, 179, 184).
3 Appellant actually refers to "underestimat[ing]" oil amount, but it is clear
from the context that overestimating was intended. Appeal Br. 5---6.
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Application 12/203,164
The Examiner responds that He "teaches the importance of knowing
how much oil remains in the different components of the system [such as the
condenser and the evaporator] in order to ensure proper lubrication of the
compressor" (emphasis added) (citing He i-fi-1 2-6), and He applies to
different kinds of compressors and HV AC systems (citing He i1 42). Ans. 5.
Based on these considerations, the Examiner maintains it would have been
obvious to modify Christensen's control to estimate the oil quantity by
measuring a condition at both the condenser and the evaporator, to improve
Christensen's system "by accurately estimat[ing the] quantity of oil in the
compressor and thus, ensure good lubrication goes into the compressor, and
thus ensure the safe operation of the compressor." Id. at 5---6.
We note, first, that the Examiner refers to modifying Christensen's
"control (82, 92)" to measure conditions at both the condenser and the
evaporator. Final Act. 2-3, 6. Christensen correspondingly discloses two
different controls, control 82 and control 92, used in different embodiments.
Christensen, i134 and Fig. 4 (control 82), i136 and Fig. 5 (control 92). To
the extent the Examiner finds control 82 and control 92 are the same control,
the Examiner errs. Id. Christensen does indicate "combinations of
techniques discussed above for determining when ... to control a
compressor speed ... may be used." Id. i137. However, the Examiner does
not propose combining control 82 with control 92, does not discuss how
such a combination relates to the subject matter of claim 1, and does not
provide any reasons for such a combination. Final Act. 2-6. We, therefore,
consider the Examiner's proposed modification to each control 82 and 92
separately.
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Appeal2014-006272
Application 12/203,164
Christensen's control 82 "is configured to monitor an oil level
indicator 84 in a compressor 80" in order to determine when that oil level is
too low. Christensen, i-f 34 and Fig. 4. If control 82 determines the oil level
in compressor 80 is too low, control 82 increases the speed of
compressor 80, thereby increasing the rate of oil return to compressor 80
from other components in the refrigeration system, such as the condenser
and the evaporator. Id. i-fi-13 and 34, Fig. 4. That is, control 82 functions to
ensure compressor 80 is adequately lubricated, and directly monitors the oil
level within compressor 80 to achieve that function.
The Examiner concludes the reliability of Christensen's system would
be improved if control 82 were modified to monitor pressure or temperature
at the condenser and the evaporator, rather than oil level indicator 84 in
compressor 80, to determine whether the oil level in compressor 80 is too
low. Final Act. 2-3, 6. It would seem, however, that a direct measurement
of the variable of interest (i.e., oil level in compressor 80) via indicator 84
would be more reliable than an indirect measurement of the variable of
interest via pressure or temperature sensors in the condenser and the
evaporator. The Examiner does not cite to any evidence indicating, or
provide any technical reasoning explaining why, the proposed modification
would nonetheless improve reliability. Final Act. 6; Ans. 5---6. The
Examiner cites paragraphs 2---6 of He (Ans. 5), which discuss using "costly
viscosity sensors at the bottom of the compressor" (He i-f 6) to measure the
oil concentration in the oil/refrigerant mixture in the compressor. He further
indicates condenser and evaporator temperature sensors may be used to
estimate the oil concentration "without an expensive viscosity sensor." He
i-f 44. These disclosures in He indicate that the viscosity sensors at the
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Application 12/203,164
compressor are expensive, not that they are less reliable than temperature
sensors at the condenser and the evaporator. For these reasons, we conclude
the Examiner's determination that it would have been obvious to modify
Christensen's control 82 in the manner proposed to improve reliability is not
supported by a preponderance of the evidence, or sufficient technical
reasoning, to establish a rational basis for making the modification.
Christensen's control 92 "monitor[s] a pressure sensor 94, a
temperature sensor 96, and a gas speed sensor 98" in order to determine
when the oil level within compressor 100 is too low. Christensen, i-f 36 and
Fig. 5. If control 92 determines the oil level in compressor 100 is too low,
control 92 increases the speed of compressor 100, thereby increasing the rate
of oil return to compressor 100 from other components in the refrigeration
system, such as the condenser and the evaporator. Id. i-fi-13 and 36, Fig. 5.
That is, control 92 functions to ensure compressor 100 is adequately
lubricated, and indirectly monitors the oil level within compressor 100 to
achieve that function.
The Examiner concludes the reliability of Christensen's system would
be improved if control 92 were modified to monitor pressure or temperature
at the condenser and the evaporator, rather than the locations identified in
Figure 5. 4 Final Act. 2-3, 6. We appreciate that He discloses indirectly
monitoring the oil level within a compressor by monitoring the temperature
of the condenser and the evaporator. He i-fi-12-3, 8, 39. However, the
4 It is not clear whether temperature sensor 96 in Figure 5 measures the
temperature of the evaporator, or the gas line exiting the evaporator. Even if
sensor 96 measures the temperature of the evaporator, Christensen does not
disclose monitoring conditions at the condenser, as claimed.
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Application 12/203,164
Examiner does not cite to any evidence indicating, or provide any technical
reasoning explaining why, the proposed modification would improve
reliability. Final Act. 6; Ans. 5---6. We, therefore, conclude the Examiner's
determination that it would have been obvious to modify Christensen's
control 92 in the manner proposed to improve reliability is not supported by
a preponderance of the evidence, or sufficient technical reasoning, to
establish a rational basis for making the modification.
For the foregoing reasons, we determine the Examiner's rejection of
claim 1 fails to establish a rational basis, supported by a preponderance of
the evidence, for modifying Christensen's control 82 or control 92 to
monitor oil level in a compressor by monitoring pressure or temperature
conditions at a condenser and an evaporator. The other independent
claims 8 and 13, similarly to claim 1, recite "the estimated quantity of oil [is]
calculated over time based upon a condition measured at both a condenser
and an evaporator." Appeal Br. 16, 17 (Claims App.). The Examiner's
obviousness rationale in rejecting claims 8 and 13 is the same as for claim 1.
Final Act. 2---6. Further, the Examiner's consideration of dependent
claims 2, 4---6, 9, 10, 12, 14, 15, and 17-19 does not cure the deficiency
noted above. Id. Thus, we do not sustain the rejection of claims 1, 2, 4---6,
8-10, 12-15, and 17-19 as unpatentable over Christensen, Lifson, and He.
DECISION
The Examiner's decision to reject claims 1, 2, 4---6, 8-10, 12-15, and
17-19 as unpatentable over Christensen, Lifson, and He is not sustained.
REVERSED
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