Ex Parte Chang et al

Patent Trial and Appeal Board

Jun 28, 2018

14015344 (P.T.A.B. Jun. 28, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/015,344 08/30/2013
28395 7590 07/02/2018
BROOKS KUSHMAN P.C./FG1L
1000 TOWN CENTER
22NDFLOOR
SOUTHFIELD, MI 48075-1238
FIRST NAMED INVENTOR
Xiaoguang Chang
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.
83387080 9458
EXAMINER
KERRIGAN, MICHAEL V
ART UNIT PAPER NUMBER
3665
NOTIFICATION DATE DELIVERY MODE
07/02/2018 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, CHUAN HE,
and JOSEPHINE S. LEE
Appeal2017-007006
Application 14/015,344
Technology Center 3600
Before: LINDA E. HORNER, BRETT C. MARTIN, and
BRENT M. DOUGAL, Administrative Patent Judges.
DOUGAL, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants 1 appeal under 35 U.S.C. § 134 from a final rejection of
claims 1-8 and 10 under 35 U.S.C. §103 as being unpatentable over Jung
(US 8,390,296 B2, iss. Mar. 5, 2013) and Welchko (US 2012/0235622 Al,
pub. Sept. 20, 2012). We have jurisdiction under 35 U.S.C. § 6(b).
We reverse.
1 Appellants identify Ford Global Technologies, LLC as the real party in
interest (Appeal Br. 2).
Appeal2017-007006
Application 14/015,344
CLAIMED SUBJECT MATTER
The invention is directed to a current sensor fault detection system for
vehicles and associated methods. Claims 1, 4, and 8 are independent. Claim
1, reproduced below, is representative of the claimed subject matter:
1 A vehicle comprising:
a battery;
a sensor configured to sense a current of the battery;
an electric machine electrically connected to the battery;
and
at least one controller programmed to, in response to
detecting an error state for the sensor defined by a difference in
pre- and post-drive cycle open circuit voltages of the battery
being greater or less than a change in state of charge of the battery
for the drive cycle by a predetermined amount, reduce a power
limit of the electric machine for a subsequent drive cycle to limit
the current from the battery.
OPINION
Independent claim 1 requires, inter alia, "at least one controller
programmed to, in response to detecting an error state for the sensor defined
by a difference in pre- and post-drive cycle open circuit voltages of the
battery being greater or less than a change in state of charge of the battery
for the drive cycle .... "
The Examiner finds that "Jung's use of a current sensor ...
encompass[ es] keeping track of a state of charge (SOC) of a battery during
periods in which open circuit voltage readings are not possible or otherwise
inconvenient." Final Act. 5. The Examiner further explains that though
Jung is "silent on the terminology 'state of charge', ... Jung's disclosure is
directed toward assuring a vehicle's accumulated charge flow into/out of the
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Application 14/015,344
battery accurately corresponds to the battery's actual voltage readings."
Ans. 4.
Jung teaches that:
The controller 120 receives voltage and current values
from the voltage sensor 110 and a current sensor 140 to be
described later, respectively, during a predetermined time, and
compares variations in voltage and current over the
predetermined time with a voltage reference value and a current
reference value, respectively, to determine if abnormality exists
in the current sensor 140.
Jung 4:7-13.
The Examiner's reasoning appears to be based on Jung's teaching of
determining a "change in current over a time period" and the fact that
Wikipedia teaches that state of charge can be determined based on a "current
integration method." Final Act. 5 ( citing https://en.wikipedia.org/wiki/State
_of_charge "Current integration method").
However, even if it is possible for a state of charge to be determined
based on a measurement of current or a variation in current over time, this
fact without more, does not show that Jung teaches or suggests determining
a state of charge or a controller programmed to respond to an error state
related to a state of charge. See, e.g., Appeal Br. 4--5 ( comparing current
flow to fluid flow rate and state of charge to quantity of fluid in a container).
Further, we note that the Examiner finds "that Jung teaches using a
measured change in voltage of a battery and a measured change in current
over a common period of time ... to determine a current sensor
abnormality." Ans. 3. However, Jung does not teach comparing voltage and
current measurements over different time periods, such as to compare "pre-
and post-drive cycle open circuit voltages" and "a change in state of charge
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Application 14/015,344
of the battery for the drive cycle," as required by claim 1. See, e.g., Appeal
Br. 4.
The Examiner implicitly acknowledges that Jung does not teach
measuring or using "pre- and post-drive cycle open circuit voltages." Final
Act. 2-3. However, the Examiner explains that "Jung teaches that the time
period may be adapted to the specific application ... , so that measuring
battery voltages between drive cycles would be an obvious choice, as
relaxed battery states provide more accurate measurements (see for example
Wortham US PGPub No. 2012/0139546 i-f0023)." Id. (Wortham discusses
measuring open circuit voltage of a battery related to battery charging and
discharging methods.)
However, nothing in Jung teaches or suggests that the adaption to a
specific application would involve comparing voltage and current
measurements from different time periods such as comparing "pre- and post-
drive cycle" measurements to measurements taken during "the drive cycle"
as required by claim 1.
For these reasons, we do not sustain the rejection of claim 1 or its
dependent claims. As claim 8 includes limitations substantially similar to
claim 1, we do not sustain the rejection of claim 8 or its dependent claims
for these same reasons.
Independent claim 4 requires, inter alia, "measuring a first open
circuit voltage of a traction battery prior to start of a drive cycle; measuring
a current flow of the traction battery during the drive cycle; after vehicle
deactivation, measuring a second open circuit voltage of the traction battery;
[and] detecting an error state for a current sensor associated with the traction
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Application 14/015,344
battery based on a difference between the open circuit voltages and the
current flow."
As discussed above, nothing in Jung teaches or suggests comparing
voltage and current measurements from different time periods such as
comparing "pre- and post-drive cycle" measurements to measurements taken
during "the drive cycle." Thus, we do not sustain the rejection of claim 4 or
its dependent claims for this reason.
DECISION
The Examiner's rejection of claims 1-8 and 10 is reversed.
REVERSED
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