JOY MM DELAWARE, INC.

Patent Trials and Appeals Board

Dec 27, 2021

2020005746 (P.T.A.B. Dec. 27, 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.
13/842,707 03/15/2013 Peter M. Dalton 051077-9227-US01 2789
23409 7590 12/27/2021
MICHAEL BEST & FRIEDRICH LLP (Mke)
790 N WATER ST
SUITE 2500
MILWAUKEE, WI 53202
EXAMINER
JOSEPH, DEVON A
ART UNIT PAPER NUMBER
2846
NOTIFICATION DATE DELIVERY MODE
12/27/2021 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):
mkeipdocket@michaelbest.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte PETER M. DALTON and MICHAEL JORDAN
Appeal 2020-005746
Application 13/842,707
Technology Center 2800
Before ADRIENE LEPIANE HANLON, CATHERINE Q. TIMM, and
BRIAN D. RANGE, Administrative Patent Judges.
RANGE, 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 1 and 3–14. We have jurisdiction under
35 U.S.C. § 6(b).
We REVERSE.

1 “Appellant” refers to “applicant” as defined in 37 C.F.R. § 1.42. Appellant
identifies the real party in interest as Joy Global Underground Mining LLC.
Appeal Br. 2.
Appeal 2020-005746
Application 13/842,707

2
CLAIMED SUBJECT MATTER2
Appellant describes the invention as relating to methods and systems
for controlling drive systems such as a variable frequency drive system used
in mining equipment. Spec. ¶ 1. The Specification explains that variable
frequency drives allow alternating current motors to operate at different
speeds by generating AC voltage other than a fixed 50 Hz or 60 Hz. Id. ¶ 2.
The Specification explains that at low speed, current generated by a ground
fault is lower than normal and difficult to detect. Id. To address this
problem, the Specification describes adding a common voltage to all power
phases to allow reliable detection of ground faults at low speeds. Id. ¶ 3.
Claims 1, 8, and 11 are the independent claims on appeal. Claim 1 is
illustrative, and we reproduce it below while adding emphases to certain key
recitations:
1. A mining machine comprising:
a motor; and
a ground fault relay including a ground fault relay
controller and at least one current sensor; and
an adjustable speed drive including a variable frequency
drive controller configured to control the adjustable speed drive
to provide a voltage to the motor, the voltage having an
excitation component including a magnitude and a frequency
for operating the motor at a desired speed, the voltage further
including an additional voltage component for use in detecting
a ground fault condition, the additional voltage component
modifying the ground fault current by increasing a
magnitude of the ground fault current;

2 In this Decision, we refer to the Non-Final Office Action dated September
20, 2019 (“Non-Final Act.”), the Appeal Brief filed February 18, 2020
(“Appeal Br.”), the Examiner’s Answer dated June 11, 2020 (“Ans.”), and
the Reply Brief filed August 5, 2020 (“Reply Br.”).
Appeal 2020-005746
Application 13/842,707

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wherein the variable frequency drive controller receives
an indication from the ground fault relay controller when the at
least one current sensor detects a ground fault current that
exceeds a predetermined threshold.

Appeal Br. 17 (Claims App.).

REFERENCES
The Examiner relies upon the prior art below in rejecting the claims
on appeal:
Name Reference Date
Konrad et al. (“Konrad”) US 5,945,802 Aug. 31, 1999
Johansson et al.
(“Johansson”)
US 2009/0160454 A1 June 25, 2009
Weems II et al.
(“Weems”)
US 2012/0112758 A1 May 10, 2012

REJECTIONS
The Examiner maintains the following rejections on appeal:
A. Claims 1, 3–11, and 14 under 35 U.S.C. § 103(a) as obvious over
Konrad in view of Johansson. Non-Final Act. 3.
B. Claims 12 and 13 under 35 U.S.C. § 103(a) as obvious over Konrad,
Johansson, and Weems. Id. at 7.3

OPINION
The Examiner has the initial burden of establishing a prima facie case
of obviousness under 35 U.S.C. § 103(a). In re Oetiker, 977 F.2d 1443, 1445

3 The Office Action Summary for the Non-Final Office Action refers to
claims 1 and 3–40, but the text of the Non-Final Office Action only refers to
Appeal 2020-005746
Application 13/842,707

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(Fed. Cir. 1992) (“[T]he examiner bears the initial burden, on review of the
prior art or on any other ground, of presenting a prima facie case of
unpatentability.”). To establish a prima facie case of obviousness, the
Examiner must show that each and every limitation of the claim is described
or suggested by the prior art or would have been obvious based on the
knowledge of those of ordinary skill in the art or the inferences and creative
steps a person of ordinary skill in the art would have employed. KSR Int’l
Co. v. Teleflex Inc., 550 U.S. 398, 417 (2007); In re Fine, 837 F.2d 1071,
1074 (Fed. Cir. 1988). To resolve the issues before us on appeal, we focus
on the Examiner’s findings and determinations that relate to the error
Appellant identifies.
Rejection A, claims 1 and 3–7. The Examiner rejects claims 1 and 3–7
under 35 U.S.C. § 103(a) as obvious over Konrad in view of Johansson.
Non-Final Act. 3. The Examiner finds that Konrad teaches, for example, a
motor with a variable speed drive. Non-Final Act. 3. The Examiner finds
that Konrad does not disclose certain additional voltage component
recitations of claim 1. Id. The Examiner relies on Johansson as teaching
aspects of claim 1 relating to the additional voltage component and provides
a reason for combining the teachings of Konrad and Johansson. Id. at 4–5.
Appellant persuasively identifies two errors in the Examiner’s
position. First, Appellant argues that the Examiner does not adequately
establish that the cited references teach claim 1’s recited “the additional
voltage component modifying the ground fault current by increasing a

claims 1 and 3–14. The Appeal Brief further clarifies that only claims 1 and
3–14 are pending. Appeal Br. 4.
Appeal 2020-005746
Application 13/842,707

5
magnitude of the ground fault current” (hereinafter the “increasing
magnitude recitation”). Appeal Br. 10–11; Reply Br. 2–3. In view of the
Specification, “increasing a magnitude of the ground fault current” refers to
increasing voltage as compared to ground. Spec. ¶¶ 22, 26, 28. The
Examiner relies solely on Johansson as teaching the increasing magnitude
recitation. Non-Final Act. 4; Ans. 3–5. The cited portions of Johansson
describe injection of a voltage whose frequency is modified as compared to
the electrical machine’s frequency. Johansson ¶¶ 40–45. The Examiner does
not, however, adequately explain how Johansson teaches choosing a voltage
for the injected frequency or how the voltage is increased to meet the
increasing magnitude recitation.
Second, Appellant argues that the Examiner does not adequately
establish that the art teaches “detect[ing] a ground fault current that exceeds
a predetermined threshold” (the “predetermined threshold recitation”).
Appeal Br. 11–12; Reply Br. 2–3. In view of the Specification, the recited
“predetermined threshold” refers to a fixed value that ground fault
measurements are compared against. See, e.g., Spec. ¶¶ 25, 28. Johansson
teaches comparing measurements from at least two currents. Johansson
¶¶ 45–46. The Examiner does not, however, adequately explain how or
where Johansson suggests determining that ground fault measurements
exceed a predetermined threshold.
Due to both of the errors identified above, we do not sustain the
Examiner’s rejection of claim 1 and of the claims depending from claim 1.
Rejection A, claims 8–10. Independent claim 8 recites, among other
things, “at least one current sensor detects a ground fault current that
exceeds a predetermined threshold.” Appeal Br. 18 (Claims App.). The
Appeal 2020-005746
Application 13/842,707

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Examiner addresses this recitation similarly to claim 1’s similar
predetermined threshold recitation. Non-Final Act. 3–5. We do not sustain
the rejection of claim 8 and claims depending from claim 8 because, as we
explain above, the Examiner has not adequately explained how the cited art
teaches this recitation.
Rejection A, claims 11 and 14, and Rejection B, claims 12 and 13.
Independent claim 11 recites, among other things, “the additional voltage
signal added onto each phase of the three-phase voltage to increase a
magnitude of a ground fault current.” Appeal Br. 18 (Claims App.). The
Examiner addresses this recitation similarly to claim 1’s similar increasing
magnitude recitation. Non-Final Act. 6–7. We do not sustain the rejection of
claim 11 and claims depending from claim 11 because, as we explain above,
the Examiner has not adequately explained how the cited art teaches this
recitation. We also note that the Examiner’s use of the Weems reference to
address dependent claims 12 and 13 does not cure the error with regard to
claim 11.

DECISION SUMMARY
In summary:
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1, 3–11,
14
103(a) Konrad, Johansson 1, 3–11, 14
12, 13 103(a) Konrad, Johansson,
Weems
12, 13
Overall
Outcome
1, 3–14

REVERSED