FORD GLOBAL TECHNOLOGIES, LLCDownload PDFPatent Trials and Appeals BoardMar 12, 202014515999 - (D) (P.T.A.B. Mar. 12, 2020) Copy Citation 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). Appeal 2019-003002 Application 14/515,999 2 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 Appeal 2019-003002 Application 14/515,999 3 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: Appeal 2019-003002 Application 14/515,999 4 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. Appeal 2019-003002 Application 14/515,999 5 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 Appeal 2019-003002 Application 14/515,999 6 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 Appeal 2019-003002 Application 14/515,999 7 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 Appeal 2019-003002 Application 14/515,999 8 “[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. Appeal 2019-003002 Application 14/515,999 9 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 Appeal 2019-003002 Application 14/515,999 10 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 Copy with citationCopy as parenthetical citation