FORD GLOBAL TECHNOLOGIES, LLC

Patent Trials and Appeals Board

Mar 12, 2020

14515999 - (D) (P.T.A.B. Mar. 12, 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.
14/515,999 10/16/2014 Xiaoguang CHANG 83459212 4646
28395 7590 03/12/2020
BROOKS KUSHMAN P.C./FGTL
1000 TOWN CENTER
22ND FLOOR
SOUTHFIELD, MI 48075-1238
EXAMINER
HAWKINS, DOMINIC E
ART UNIT PAPER NUMBER
2868
NOTIFICATION DATE DELIVERY MODE
03/12/2020 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):
docketing@brookskushman.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte XIAOGUANG CHANG, XU WANG, and CHUAN HE
Appeal 2019-003002
Application 14/515,999
Technology Center 2800
Before LINDA M. GAUDETTE, MONTÉ T. SQUIRE, and
AVELYN M. ROSS, Administrative Patent Judges.
GAUDETTE, Administrative Patent Judge.
DECISION ON APPEAL1
The Appellant2 appeals under 35 U.S.C. § 134(a) from the Examiner’s
decision finally rejecting claims 1–15.3
We REVERSE.

1 This Decision includes citations to the following documents: Specification
filed October 16, 2014 (“Spec.”); Final Office Action dated March 26, 2018
(“Final”); Appeal Brief filed September 26, 2018 (“Appeal Br.”);
Examiner’s Answer dated January 4, 2019 (“Ans.”); and Reply Brief filed
March 4, 2019 (“Reply Br.”).
2 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. The Appellant identifies the real party in interest as Ford
Global Technologies, LLC. Appeal Br. 2.
3 We have jurisdiction under 35 U.S.C. § 6(b).
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Application 14/515,999

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CLAIMED SUBJECT MATTER
The invention relates to a method and an apparatus for chassis
electrical leakage path detection. Spec. ¶ 1. According to the Specification,
“[c]onventional electric vehicles may be equipped with a high voltage
traction battery for use as a primary source of power and an auxiliary battery
for use in powering various electrical components.” Id. ¶ 2. Although the
high voltage traction battery typically is isolated from the vehicle chassis, a
short circuit may occur between the traction battery and the vehicle body. Id.
An embodiment of the invention is illustrated in Figure 1, reproduced below.

“Figure 1 is a schematic circuit diagram 100 of a leakage path current
detection sensor measuring a battery pack voltage and a positive leakage
voltage of a high voltage system . . . .” Spec. ¶ 15. Circuit diagram 100
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represents a high voltage system that includes battery pack voltage sensor
102, leak voltage sensor 104, positive contactor driver 106, negative
contactor driver 108, positive contactor 110, negative contactor 112, and
estimate models of positive leakage resistance 116 and of negative leakage
resistance 114. Id. A vehicle computing system (not shown) may control the
contactor drivers 106, 108 and receive data from battery pack voltage sensor
102 and leak voltage sensor 104. Id. Leak voltage sensor 104 has a ground
connection via capacitor 130a. Id. ¶ 16. When main contactors 110, 112 are
closed and the battery is requested to power electrical motor 132 for
propulsion of the hybrid vehicle, the system may estimate the leakage
resistance (i.e., leakage level) of the high voltage system based on a current
flowing through battery 122, leakage detection resistors R1 (126a, 126b) and
R2 (128a, 128b), positive leakage resistance RLP 116, and negative leakage
resistance RLN 114. Id. ¶ 17.
Claims 1 and 11, reproduced below, are illustrative of the claimed
subject matter:
l . A vehicle comprising:
a battery pack;
an electric motor;
a contactor configured to electrically connect the battery
pack and motor;
control circuitry for the contactor including a leak
voltage detection sensor; and
a controller programed to output a leakage resistance
between the battery pack and a chassis of the vehicle based on a
leak voltage detected by the sensor and corresponding to a leak
current that flows through the contactor.
11. A method for detecting battery leakage in a vehicle
comprising:
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in response to closing of a contactor configured to
electrically connect a traction battery to a motor, outputting a
resistance of a leakage path between the traction battery and a
chassis of the vehicle based on a leakage current that flows
through the contactor and to the chassis.
REFERENCES
The Examiner relies on the following prior art as evidence of
unpatentability:
Name Reference Date
Kito US 2004/0243288 A1 Dec. 2, 2004
Furukawa US 2006/0006840 A1 Jan. 12, 2006
Bertness US 2014/0002021 A1 Jan. 2, 2014
Inoue US 2014/0368211 A1 Dec. 18, 2014
Pan US 2015/0063582 A1 Mar. 5, 2015

REJECTIONS
1. Claims 1, 3, and 4 are rejected under 35 U.S.C. § 102(a)(2) as
unpatentable over Inoue. Final 5.
2. Claim 2 is rejected under 35 U.S.C. § 103 as unpatentable over
Inoue in view of Bertness. Final 7.
3. Claim 5 is rejected under 35 U.S.C. § 103 as unpatentable over
Inoue in view of Pan. Final 7.
4. Claims 6–8 and 10 are rejected under 35 U.S.C. § 103 as being
unpatentable over Bertness in view of Inoue. Final 8.
5. Claim 9 is rejected under 35 U.S.C. § 103 as unpatentable over
Bertness in view of Inoue and Pan. Final 11.
6. Claims 11–15 are rejected under 35 U.S.C. § 103 as
unpatentable over Furukawa in view of Kito. Final 11.
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OPINION
Claims 1–10
The Examiner rejected claims 1, 3, and 4 as anticipated by Inoue. See
Final 5. The Examiner rejected claims 2 and 5–10 as unpatentable over
Inoue in combination with one or more additional references. See id.
at 7–11. Inoue discloses a ground leakage detector for an electric vehicle.
Inoue Abstract. The Examiner found that claim 1 reads on Inoue Figure 2,
reproduced below, and the corresponding description thereof in Inoue
paragraph 60. Final 5–6.

Inoue Figure 2 is a block diagram showing electric components and
wires of an electric motorcycle’s electric system. Inoue ¶ 33. Battery unit 60
serves as a high-voltage and DC power single secondary battery, and
includes a plurality of battery modules 61 that are electrically connected in
series. Id. ¶ 57. Battery unit 60 is electrically and mechanically connected to
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inverter 20 via high-voltage electric wire 31 composed of P-side power
supply wire 31p and N-side power supply wire 31n. Id. ¶ 58. Inverter 20
converts the high-voltage DC power supplied from battery unit 60 into
three-phase AC power, and supplies the three-phase AC power to electric
motor 5 via three-phase AC wire 32. Id. P-side inverter relay 36 is provided
on P-side power supply wire 31p and N-side inverter relay 37 is provided on
N-side power supply wire 31n of high-voltage electric wire 31. Id. ¶ 59.
In-vehicle ground leakage detector 300 is electrically connected to
wire 301 which branches from high-voltage electric wire 31 in a location
between battery unit 60, and inverter relays 36, 37. Id. ¶ 60. In-vehicle
ground leakage detector 300 is connected to vehicle body frame 4, which is
maintained at a ground potential via ground wire 302, in addition to
high-voltage wire 301 that branches from high-voltage electric wire 31 at a
location between battery unit 60 and inverter relays 36, 37. Id. In-vehicle
ground leakage detector 300 is configured to detect the presence of a ground
leakage path from battery unit 60 to vehicle body frame 4 according to
voltage drops generated in ground leakage detecting resistors. Id. In-vehicle
ground leakage detector 300 may directly activate inverter relays 36, 37 to
disconnect battery unit 60 from inverter 20 if a ground leakage in battery
unit 60 is detected. Id.
The Examiner found that the claim 1 language “a contactor configured
to electrically connect the battery pack and motor” reads on Inoue’s wires
31p, 31n and relays 36, 37 that electrically connect battery unit 60 to motor
5. Final 5. The Examiner found that the claim 1 language “control circuitry
for the contactor including a leak voltage detection sensor” reads on Inoue’s
ground leakage detector 300 and circuitry that controls relays 36, 37. Id. at
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5–6. As to the last paragraph of claim 1, the Examiner found that either
leakage detector 300’s circuitry or vehicle body control unit 59 is “a
controller programed to output a leakage resistance” between battery unit 60
and vehicle chassis 4 corresponding to a leak current that flows through
Inoue’s wires 31p, 31n and relays 36, 37. Id. at 6.
The Appellant argues that the Examiner erred reversibly in finding
that Inoue discloses “a controller programed to output a leakage resistance . .
. corresponding to a leak current that flows through the contactor” (claim 1).
Appeal Br. 3. The Appellant argues that Inoue detects whether current is
flowing from battery unit 60 through vehicle ground leakage detector 300 to
ground. Id. The Appellant argues that the leakage path does not include
relays 36, 37, and notes that if the leakage did flow through closed relays 36,
37, “it would also flow through electric motor 5 . . . which does not make
sense.” Id. at 4.
In response to this argument, the Examiner asserts that the broadest
reasonable interpretation of the claim term “contactor” reads on a wire that
connects battery unit 60 to motor 5. Ans. 6. The Examiner contends that
because wire 31 is electrically connected to ground leakage detector 300
“whatever leakage is in the contactors of 31 would also be based on what is
sensed between the battery and the chassis.” Id.
We agree with the Appellant that the Examiner’s rejection of claim 1
is based on an overly-broad interpretation of the claim term “contactor” as
reading on a wire. Reply Br. 2. As argued by the Appellant, during
prosecution, claim language is read in light of the specification as it would
be interpreted by one of ordinary skill in the art. In re Suitco Surface, Inc.,
603 F.3d 1255, 1260 (Fed. Cir. 2010). The Specification discloses that
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“[w]hen the vehicle is not in use, the at least two contactors may be opened
and isolate the battery system from the electric load. When the vehicle is in
use, the contactors are closed and the battery system communicates to the
electric load.” Spec. ¶ 13; see also id. ¶ 43 (“If the contactors are closed, the
method may measure the battery pack voltage . . . via the battery pack
voltage sensor. If the contactors are open, the method may be in a wait state
for a predefined amount of time before checking to see if the high voltage
battery is enabled . . . .”).
Based on the description in the Specification, we construe the term
“contactor” as referring to a structure that is capable of opening or closing a
circuit. We find no support in the claims or Specification for the Examiner’s
interpretation of the claim term “contactor” as reading on a wire, i.e., a
structure that is not capable of opening a circuit. Therefore, we are
persuaded of reversible error in the Examiner’s finding that the italicized
language in the claim 1 limitation “a controller programed to output a
leakage resistance between the battery pack and a chassis of the vehicle . . .
corresponding to a leak current that flows through the contactor” (emphasis
added) reads on a current that flows through Inoue’s wire 31. To the extent
that the Examiner still contends that this claim language reads on a current
that flows through Inoue’s relays 36, 37, we agree with the Appellant that
the Examiner has not explained with sufficient clarity how Inoue’s leakage
path between battery unit 60 and vehicle chassis 4 includes these relays.
Accordingly, we do not sustain the rejection of claim 1. Because the
Examiner’s rejections of claims 2–10 are based on the same unsupported
findings, we also do not sustain these rejections. See Final 6–11; Appeal Br.
4–5.
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Claims 11–15
The Examiner rejected claims 11–15 as unpatentable over Furukawa
and Kito. See Final 11. Furukawa “relates to a power supply apparatus that
drives a motor for running an electric vehicle, . . . and particularly to a power
supply apparatus for a vehicle capable of accurately detecting a leakage that
occurs in the output side of a driving battery with [a] simple circuit
configuration.” Furukawa ¶ 1. Furukawa discloses an embodiment in which
“a leakage test resistance is connected between the driving battery and the
chassis through a switching element, and the voltage detection circuit detects
the leakage resistance in the state where the switching element is turned ON
to connect the driving battery to the chassis with the leakage test resistance.”
Id. ¶ 12.
The Examiner found that Furukawa discloses Appellant’s claim 11
method with the exception that Furukawa does not disclose explicitly that
the contactor (switching element 17) is configured to electrically connect the
battery (driving battery 1) to a motor. Final 11–12; see Ans. 8–9 (citing
Furukawa ¶ 36, Fig. 2). The Examiner found that Kito discloses a contactor
(relay 62) configured to connect battery 10 to motor 15. Id. at 12; see Kito
¶¶ 34, 39, Fig. 1. The Examiner determined that “[i]t would have been
obvious to a person having ordinary skill in the art before the effective filing
date of the claimed invention to combine Furukawa in view of Kito because
it is known in the art that an electric motor is driv[en] by a power supply.”
Final 12 (citing Furukawa ¶ 2).
The Appellant has argued persuasively that the Examiner’s rejection
is based on improper hindsight reasoning. See Appeal Br. 6; Reply Br. 2–3.
“The mere fact that the prior art may be modified in the manner suggested
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by the Examiner does not make the modification obvious unless the prior art
suggested the desirability of the modification.” In re Fritch, 972 F.2d 1260,
1266 (Fed. Cir. 1992). The Examiner has not identified a prior art teaching
suggesting the desirability of modifying Furukawa to connect the battery to a
motor via the contactor, nor has the Examiner offered other convincing
explanation as to why the ordinary artisan would have had a reason to make
this modification. Accordingly, we do not sustain the rejection of claims
11–15.
CONCLUSION
The Appellant has identified reversible error in the Examiner’s
rejections of claims 1–15.
DECISION SUMMARY
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1, 3, 4 102(a)(2) Inoue 1, 3, 4
2 103 Inoue, Bertness 2
5 103 Inoue, Pan 5
6–8, 10 103 Bertness, Inoue 6–8, 10
9 103 Bertness, Inoue,
Pan
9
11–15 103 Furukawa, Kito 11–15
Overall
Outcome
1–15

REVERSED