DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 17 April 2026 has been entered.
Response to Arguments
Applicant argues that the combination of Vaughan as modified by Gale does not sufficiently teach “control delivery of power to both the first electric vehicle and the second electric vehicle responsive to a comparison of the resistance at the first one or more first resistors and the resistance at the one or more second resistors with a threshold” from the claim set filed 24 October 2025. The broadest reasonable interpretation of the limitation as filed on 24 October 2025 simply compares the first and second resistors to a single threshold.
This limitation has been amended to “control delivery of power to both the first electric vehicle and the second electric vehicle responsive to a first comparison of the first resistance with a first threshold and a second comparison of the second resistance with a second threshold”. Vaughan discloses a dynamic power allocation system for charging multiple electric vehicles, wherein each dispenser contains an isolation detect unit 865. This is described in Vaugahn ¶0082 “The dispenser 800 will terminate a charge when the isolation of either rail to ground is under a certain amount”. However, Vaughan does not disclose the topology of the isolation detect 865. Gale discloses a method and system for electrical bus isolation while charging an electric vehicle, which is used as the isolation detect 865 in the system as taught by Vaughan. Gale describes determining the isolation threshold in ¶0028 “unbalanced resistance component can be calculated using R.sub.lp and R.sub.lm as follows [Equation 7]”, resulting in a threshold determined by the components of the circuit. The first resistance with a first threshold would correspond to the one or more first resistors attached to a first dispenser, and the second threshold would correspond to the one or more second resistors attached to a second dispenser. The resistances would be dependent on the specific components in each dispenser as well as the specific car requesting power at each of them resulting in a separate first threshold and second threshold.
The limitation “determine (i) a first resistance between the first direct current bus and ground and (ii) a second resistance between the second direct current bus and the ground”, which simply states to determine or calculate a resistance of a resistor between a first DC bus and the ground and of a resistor between a second DC bus and the ground. This feature is disclosed in Gale ¶0022 “FIG. 3 shows apparatus for detecting leakage resistance wherein a first detector circuit 45 is arranged between positive bus 31 and chassis ground 40 and a second detector circuit 46 is arranged between negative bus 32 and chassis ground 40”. Gale further discloses in ¶0029 “step 73, leakage resistances R.sub.LP and R.sub.LM are calculated”, which would correlate to an isolation resistance of the dispenser.
Applicant argues that the leakage resistance calculated in Gale step 73 does not teach the claim 1 limitation “one or more first resistors connected to a first terminal of a first direct current bus of a first charger” and “one or more second resistors connected to a second terminal of a second direct current bus of a second charger”. Gale alone does not teach these limitations; however, Vaughan as modified by Gale does teach the limitations “one or more first resistors connected to a first terminal of a first direct current bus of a first charger” and “one or more second resistors connected to a second terminal of a second direct current bus of a second charger”. Vaughan discloses a dynamic power allocation system for charging multiple electric vehicles, wherein each dispenser contains an isolation detect unit 865. This is described in Vaugahn ¶0082 “The dispenser 800 will terminate a charge when the isolation of either rail to ground is under a certain amount”. However, Vaughan does not disclose the topology of the isolation detect 865. Gale discloses a method and system for electrical bus isolation while charging an electric vehicle, which is used as the isolation detect 865 in the system as taught by Vaughan. This modification results in having “one or more first resistors connected to a first terminal of a first direct current bus of a first charger” and “one or more second resistors connected to a second terminal of a second direct current bus of a second charger”.
Applicant's arguments filed 17 April 2026 have been fully considered but they are not persuasive.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
Claim 1, 11, and 19 are rejected under 35 U.S.C. 112(b) as failing to set forth the subject matter which the inventor or a joint inventor regards as the invention. The claims recite the limitation “a first resistor of the one or more first resistors in parallel with a second resistor of the one or more first resistors” which does not distinctly claim the subject matter which the inventor regards as the invention. Applicant specification describes this in ¶¶, indicating that the underlined portion “of the one or more first resistors” are the set of resistors attached to the first charging dispenser and the italicized portion “a first resistor” and “a second resistor” are a subset of resistors attached to the first charging dispenser. Similarly for the limitation “a first resistor of the one or more second resistors in parallel with a second resistor of the one or more second resistors”.
Similarly as applied to 3-7, 13-16, 20, and 24-27 regarding the “a first resistor of the one or more first resistors” and “a second resistor of the one or more second resistors”.
The claims as currently written do not sufficiently distinguish between “the first one or more resistors” and “a first resistor”, similarly as applied to “the one or more second resistors” and “a second resistor”. Examiner suggests renaming the “a first resistor” and “a second resistor” to “resistor connected to the negative bus” and “resistor connected to the positive bus” respectively, as supported by applicant specification ¶0043 “resistor 210 can be connected to the negative bus 232, the resistor 212 can be connected to the positive bus 230, the resistor 214 can be connected to the negative bus 228, the resistor 216 can be connected to the positive bus 226, the resistor 218 can be connected to the negative bus 224, and the resistor 220 can be connected to the positive bus 222”. This would help distinguish between the plurality of resistors attached to each dispenser, and the plurality of resistors attached to all the dispensers.
Claim 23 is rejected under 35 U.S.C. 112(b) as failing to set forth the subject matter which the inventor or a joint inventor regards as the invention. Claim 23 contains the limitation “prevent delivery of power to the first electric vehicle; and deliver power to the second electric vehicle” wherein the semicolon is improperly separating the limitation. The preceding clause “(i) the first resistance being less than the first threshold and (ii) the second resistance being larger than the second threshold”, based on the application as a whole this indicates that “(i) the first resistance being less than the first threshold” prevents delivery of power to the first electric vehicle and “(ii) the second resistance being larger than the second threshold” allows power to be delivered to the vehicle. The claim as written indicates that when both (i) and (ii) are true then only power is prevented from being delivered to a first electric vehicle. The semicolon severs the delivery of power to the second electric vehicle from any actionable limitation. Appropriate correction is required.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claim(s) 1, 3-7, 11, 13-16, and 19-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Vaughan et al (US 20170274792 A1) modified by Gale et al (US 20160096433 A1).
Regarding claim 1, Vaughan teaches system, comprising: one or more first resistors connected to a first terminal of a first direct current bus of a first charger, the first charger configured to deliver power to a first electric vehicle, (¶0017 "power buses 140A-B are coupled with the DC output terminal 135, which itself is coupled with the EVSE 150A over the output 152A (corresponding with the power bus 140A) and coupled with the dispenser 150B over the output 152B (corresponding with the power bus 140B)")
[and a first resistor of the one or more first resistors in parallel with a second resistor of the one or more first resistors;]
one or more second resistors connected to a second terminal of a second direct current bus of a second charger, the second charger configured to deliver power to a second electric vehicle, (¶0017 "power buses 140A-B are coupled with the DC output terminal 135, which itself is coupled with the EVSE 150A over the output 152A (corresponding with the power bus 140A) and coupled with the dispenser 150B over the output 152B (corresponding with the power bus 140B)")
[and a first resistor of the one or more second resistors in parallel with a second resistor of the one or more second resistors;]
and a controller (¶0081 "dispenser 800 includes the operating system 810 that is coupled with the embedded microcontroller 815")
[comprising circuitry configured to: determine (i) a first resistance between the first direct current bus and ground at the one or more first resistors
and (ii) a second resistance between the second direct current bus and the ground;]
and control delivery of power to both the first electric vehicle and the second electric vehicle (¶0052 “ FIG. 4 is a flow diagram that illustrates exemplary operations for allocating power modules”)
[responsive to a first comparison of the first resistance at the one or more first resistors with a first threshold and a second comparison of the second resistance at the one or more second resistors with a second threshold.]
Vaughan ¶0081 further discloses “[FIG 8] The dispensers 150A-D may take the form of the dispenser 800”, depicting an isolation detect module 865 and described in ¶0082. The purpose of isolation detect module 865 is to confirm isolation of any of the DC rails corresponding to dispensers 150A-D. Vaughan does not teach and a first resistor of the one or more first resistors in parallel with a second resistor of the one or more first resistors; comprising circuitry configured to: determine (i) a first resistance between the first direct current bus and ground at the one or more first resistors and (ii) a second resistance between the second direct current bus and the ground; [and control delivery of power to both the first electric vehicle and the second electric vehicle] responsive to a first comparison of the first resistance at the one or more first resistors with a first threshold and a second comparison of the second resistance at the one or more second resistors with a second threshold.
Gale teaches and a first resistor of the one or more first resistors in parallel with a second resistor of the one or more first resistors; (¶0022 “FIG. 3 shows apparatus for detecting leakage resistance wherein a first detector circuit 45 is arranged between positive bus 31 and chassis ground 40 and a second detector circuit 46 is arranged between negative bus 32 and chassis ground 40”, First detector circuit 45 comprises current-limiting resistor 50 in series with current-sensing resistor 52 to form a first one or more resistors and is in parallel with second detector circuit comprising current-limiting resistor 53 in series with current-sensing resistor 55)
comprising circuitry configured to: determine (i) a first resistance between the first direct current bus and ground at the one or more first resistors (FIG 3 first detector circuit 45 comprising limiting resistor 50 in series with current-sensing resistor 52 connects bus 31 to ground)
and (ii) a second resistance between the second direct current bus and the ground; (FIG 3 second detector circuit 46 comprising limiting resistor 53 in series with current-sensing resistor 55 connects bus 32 to ground)
[and control delivery of power to both the first electric vehicle and the second electric vehicle] responsive to a first comparison of the first resistance at the one or more first resistors with a first threshold (¶0029 “step 73, leakage resistances R.sub.LP and R.sub.LM are calculated. The smaller of the two resistances is chosen in step 74 in order to identify a worst-case bus leakage resistance” as applied to limiting resistor 50 in series with current-sensing resistor 52, ¶0030 “step 76, the isolation value is compared to an isolation threshold. If less ii) than the threshold, then the invention signals an atypical condition in step 77 (e.g., by notifying the driver or disconnecting power to the high-voltage buses)” as applied to limiting resistor 50 in series with current-sensing resistor 52 and a first threshold)
and a second comparison of the second resistance at the one or more second resistors with a second threshold. (¶0029 “step 73, leakage resistances R.sub.LP and R.sub.LM are calculated. The smaller of the two resistances is chosen in step 74 in order to identify a worst-case bus leakage resistance” as applied to limiting resistor 53 in series with current-sensing resistor 55, ¶0030 “step 76, the isolation value is compared to an isolation threshold. If less ii) than the threshold, then the invention signals an atypical condition in step 77 (e.g., by notifying the driver or disconnecting power to the high-voltage buses)” as applied to limiting resistor 50 in series with current-sensing resistor 52 and a first threshold)
Therefore it would be obvious to one of ordinary skill in the art, before the effective filing date, to modify the system as taught by Vaughan to use the isolation circuitry and methodology of Gale in place of isolation detect module 865. Vaughan discloses a dynamic allocation of power for multiple electric vehicles simultaneously, described in ¶0082 “isolation detect module 865 manages the isolation sensor 825 to detect whether the circuits are isolated… dispenser 800 will terminate a charge when the isolation of either rail to ground is under a certain amount”. Gale discloses an electrical bus isolation method and system for charging an electric vehicle. It would have been obvious to try using the topology disclosed in Gale FIG 3 as the isolation detect module 865 of Vaughan. The modification would be obvious because one of ordinary skill in the art would be motivated to prevent ground faults thereby protecting users from electric shock and safeguarding sensitive components from damage.
Similarly for claim 11 as applied to a method. (Gale FIG 7)
Similarly for claim 19 as applied to a system to deliver power to electric vehicles. (Vaughan Cabinet 110 through Dispensers 150)
Regarding claim 3, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches comprising wherein: the one or more first resistors comprising a first resistor connected in parallel with a second resistor, (¶0022 “FIG. 3 shows apparatus for detecting leakage resistance wherein a first detector circuit 45 is arranged between positive bus 31 and chassis ground 40 and a second detector circuit 46 is arranged between negative bus 32 and chassis ground 40”, First detector circuit 45 comprises current-limiting resistor 50 in series with current-sensing resistor 52 to form a first one or more resistors and is in parallel with second detector circuit comprising current-limiting resistor 53 in series with current-sensing resistor 55)
[wherein the first threshold is set equal to a predetermined resistance of the first resistor of the one or more first resistors in parallel with the second resistor of the one or more first resistors.]
Vaughan as modified by Gale does not teach wherein the first threshold is set equal to a predetermined resistance of the first resistor of the one or more first resistors in parallel with the second resistor of the one or more first resistors.
Gale teaches wherein the first threshold is set equal to a predetermined resistance of the first resistor of the one or more first resistors in parallel with the second resistor of the one or more first resistors. (¶0028 “unbalanced resistance component can be calculated using R.sub.lp and R.sub.lm as follows [Equation 7]”, ¶0030 "step 76, the isolation value is compared to an isolation threshold")
Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to further modify the system as taught by Vaughan modified by Gale wherein the first threshold is set equal to a predetermined resistance of the first resistor of the one or more first resistors in parallel with the second resistor of the one or more first resistors as taught by Gale. The modification would be obvious because one of ordinary skill in the art would be motivated to balance the resistance between the positive and negative DC buses to protect the electric vehicle batteries from overheating or degradation.
Similarly for claim 13 as applied to a method, Vaughan as modified by Gale teaches the method of claim 11.
Regarding claim 4, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches comprising the controller to: [trigger an alert responsive to the] first resistance at the one or more first resistors being less than the first threshold. (Gale ¶0030 "step 76, the isolation value is compared to an isolation threshold")
Vaughan as modified by Gale does not teach trigger an alert responsive to the [first resistance at the one or more first resistors being less than the first threshold.]
Gale teaches trigger an alert responsive to the [first resistance at the one or more first resistors being less than the first threshold.] (¶0030 "step 76, the isolation value is compared to an isolation threshold. If less ii) than the threshold, then the invention signals an atypical condition in step 77 (e.g., by notifying the driver or disconnecting power to the high-voltage buses)")
Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to further modify the system as taught by Vaughan as modified by Gale to trigger an alert as taught by Gale. The modification would be obvious because one of ordinary skill in the art would be motivated to alert a user of a potential safety hazard.
Similarly for claim 14 as applied to a method, Vaughan as modified by Gale teaches the method of claim 11.
Regarding claim 5, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches wherein the first threshold corresponds to a known resistance of the first resistor of the one or more first resistors in parallel with the second resistor of the one or more first resistors, (Gale ¶0028 “unbalanced resistance component can be calculated using R.sub.lp and R.sub.lm as follows [Equation 7]”)
and comprising the controller to: determine that the first resistance at the one or more first resistors is less than the first threshold; (Gale ¶0030 "step 76, the isolation value is compared to an isolation threshold. If less ii) than the threshold, then the invention signals an atypical condition in step 77 (e.g., by notifying the driver or disconnecting power to the high-voltage buses)")
and prevent delivery of power to the first electric vehicle responsive to determination that the first resistance at the one or more first resistors is less than the first threshold. (Vaughan ¶0078 "The dispenser 800 will terminate a charge when the isolation of either rail to ground is under a certain amount.”)
Similarly for claim 15 as applied to a method, Vaughan as modified by Gale teaches the method of claim 11.
Similarly for claim 20 as applied to a system to deliver power to electric vehicles, Vaughan as modified by Gale teaches the system to deliver power to electric vehicles claim 19.
Regarding claim 6, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches comprising the controller to: receive an indication that the first electric vehicle is coupled to the first charger; (Vaughan ¶0026 "dispenser can charge the connected electric vehicle. The requesting dispenser may send a command to each one of the selected available power modules 115A-L directly (which may be relayed by the PCU 120) ")
and measure determine, prior to delivery of power to the first electric vehicle and responsive to the indication, the first resistance at the one or more first resistors. (Gale ¶0029 “step 73, leakage resistances R.sub.LP and R.sub.LM are calculated. The smaller of the two resistances is chosen in step 74 in order to identify a worst-case bus leakage resistance” as applied to limiting resistor 50 in series with current-sensing resistor 52)
Similarly for claim 16 as applied to a method, Vaughan as modified by Gale teaches the method of claim 11.
Regarding claim 7, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale does not teach comprising the controller to: measure determine the first resistance at the one or more first resistors based on a time interval.
Gale further teaches comprising the controller to: measure determine the first resistance at the one or more first resistors based on a time interval. (¶0031 “[FIG 7] step 81, an unbalanced leakage resistance is calculated (e.g., using Equation 7). The calculated values for the balanced and/or unbalanced resistances are compiled over time in step 82”)
Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to further modify the system as taught by Vaughan to comprise the controller to: measure determine the first resistance at the one or more first resistors based on a time interval as further taught by Gale. The modification would be obvious because one of ordinary skill in the art would be motivated to continually monitor the electrical isolation of high-voltage components to increase safety during high-voltage charging operation.
Regarding claim 21, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches comprising: the first threshold corresponding to a first known total resistance of the first resistor of the one or more first resistors in parallel with the second resistor of the one or more first resistors; (Gale ¶0029 “step 73, leakage resistances R.sub.LP and R.sub.LM are calculated. The smaller of the two resistances is chosen in step 74 in order to identify a worst-case bus leakage resistance” as applied to limiting resistor 50 in series with current-sensing resistor 52, ¶0030 "step 76, the isolation value is compared to an isolation threshold" using a first threshold)
and the second threshold corresponding to a second known total resistance of the first resistor of the one or more second resistors in parallel with the second resistor of the one or more second resistors. (Gale ¶0029 “step 73, leakage resistances R.sub.LP and R.sub.LM are calculated. The smaller of the two resistances is chosen in step 74 in order to identify a worst-case bus leakage resistance” as applied to limiting resistor 53 in series with current-sensing resistor 55, ¶0030 "step 76, the isolation value is compared to an isolation threshold" using a second threshold)
Similarly for claim 24 as applied to a method, Vaughan as modified by Gale teaches the method of claim 11.
Similarly for claim 26 as applied to a system, Vaughan as modified by Gale teaches the system of claim 19.
Regarding claim 22, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches comprising: the one or more first resistors included in a first cable, the first cable to electrically couple the first charger with the first electric vehicle, and the first threshold corresponding to a first known resistance of the first cable; (Vaughan cabinet 110 dispenser 150A and Vaughan FIG 8 shows isolation detect 865 onboard the dispenser, Gale FIG 3 shows the topology of the isolation detect circuity comprising one or more first resistors)
and the one or more second resistors included in a second cable, the second cable to electrically couple the second charger with the second electric vehicle, and the second threshold corresponding to a second known resistance of the second cable. (Vaughan cabinet 110 dispenser 150B and Vaughan FIG 8 shows isolation detect 865 onboard the dispenser, Gale FIG 3 shows the topology of the isolation detect circuity comprising one or more second resistors)
Similarly for claim 25 as applied to a method, Vaughan as modified by Gale teaches the method of claim 11.
Similarly for claim 27 as applied to a system, Vaughan as modified by Gale teaches the system of claim 19.
Regarding claim 23, Vaughan as modified by Gale teaches the system of claim 1. Vaughan as modified by Gale further teaches wherein the first threshold corresponds to a first known resistance of the one or more first resistors, (Gale ¶0028 “unbalanced resistance component can be calculated using R.sub.lp and R.sub.lm as follows [Equation 7]” as applied to Vaughan dispenser 150A, Gale ¶0030 "step 76, the isolation value is compared to an isolation threshold")
wherein the second threshold corresponds to a second known resistance of the one or more second resistors, (Gale ¶0028 “unbalanced resistance component can be calculated using R.sub.lp and R.sub.lm as follows [Equation 7]” as applied to Vaughan dispenser 150B, Gale ¶0030 "step 76, the isolation value is compared to an isolation threshold")
and comprising the controller to: detect that (a) the first resistance is less than the first threshold and (b) the second resistance is larger than the second threshold; (Gale ¶0030 "step 76, the isolation value is compared to an isolation threshold. If less ii) than the threshold, then the invention signals an atypical condition in step 77 ")
and responsive to detection of (i) the first resistance being less than the first threshold and (ii) the second resistance being larger than the second threshold: (Gale ¶0025 “[Equation 6] The resulting isolation value is compared with an isolation threshold (e.g., 500 ohms/volt), and if it is less than the threshold then the invention signals that an atypical condition has been detected”)
prevent delivery of power to the first electric vehicle; and deliver power to the second electric vehicle. (Vaughan ¶0078 "The dispenser 800 will terminate a charge when the isolation of either rail to ground is under a certain amount.”)
Prior Art Not Relied Upon
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure can be found in the attached PTO-892 Notice of References Cited by Examiner attached to this correspondence.
Hasan et al (US 20110218745 A1) discloses a method of monitoring electric isolation of a high voltage DC bus to detect ground faults during electric vehicle charging.
Al et al (US 20230280384 A1), Al has a filing date of 7 March 2022, discloses an isolation resistance monitoring system for high voltage buses delivering power during electric vehicle charging.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LISA M KOTOWSKI whose telephone number is (571)270-3771. The examiner can normally be reached Monday-Friday 8a-5p.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Julian Huffman can be reached at (571) 2722147. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/LISA KOTOWSKI/Examiner, Art Unit 2859
/JULIAN D HUFFMAN/Supervisory Patent Examiner, Art Unit 2859
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