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 .
Claim Interpretation
Independent claim 1 recites “… an anode internal pressure of the fuel cell stack”, and “the anode internal pressure”. The disclosure teaches “The internal pressure of the low-pressure fuel pipe 12 a is equal to the anode internal pressure” (P35.76 of PGPUB) and therefore the anode internal pressure (of the fuel cell stack) is interpreted as the pressure of a pipe section directly connected to a fuel cell.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-3 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Yoshida et al. (JP 2005216519A).
Regarding claim 1, Yoshida teaches a fuel cell system comprising: a fuel cell stack 20; a fuel tank 54; a fuel pipe 1 connecting the fuel cell stack 20 and the fuel tank 54 (P9-13; Fig. 1);
a fuel regulator A2 disposed in the fuel pipe and configured to regulate a flow rate of fuel gas to be supplied from the fuel tank to an anode of the fuel cell stack (P13-34); a fuel stop valve A3 disposed in the fuel pipe; and a controller 60, wherein
the controller 60 is configured to execute, when activating or stopping the fuel cell stack:
a first process of opening the fuel stop valve A3 and the fuel regulator A2/A6 (P16);
a second process of closing the fuel stop valve A3 and the fuel regulator A2/A6 when an anode internal pressure of the fuel cell stack reaches a predetermined first anode pressure Pk1 (P17; Fig. 2); and
a third process of outputting a signal, or initiating abnormal stopping, indicating occurrence of fuel leakage when the anode internal pressure P2 after a predetermined first period is lower than a predetermined second anode pressure (P19).
Examiner notes the fuel regulator of Yoshida as i.e., A2 or A7, wherein A2 regulates the flow between high and low pressure, and A7 responds with A2 (auto closing/opening in response to flow/pressure). The selection of a known material and/or entity based on its suitability for its intended use supported a prima facie obviousness determination. MPEP 2144.07
Regarding claim 2, Yoshida teaches a fuel tank valve A1 attached to the fuel pipe between the fuel stop valve A3 and the fuel tank 54; and an exhaust fuel valve A5 configured to stop discharge of gas from an anode gas outlet 33 of the fuel cell stack (P11.22).
Yoshida teaches that as impurities such as water (nitrogen and moisture) can be contained in anode off gas and controlling the fuel exhaust valve via opening and closing to remove a portion of them. When condensed water accumulates in gas channels, there is a risk of flooding and the controller is configured to implement a drainage process. To do so, before execution of another process, or the first, second, and third process, a process of causing the pressure fluctuations for drainage, where all the valves are opened to increase consumption of fuel and exhaust fuel valve A5 is opened to exhaust gas outside the system (P20-26), wherein the fuel stop valve A2 and exhaust valve A5 are open and closed, and when an internal pressure of the fuel pipe on an upstream side of the fuel stop valve reaches an upper limit anode pressure higher than the predetermined first anode pressure, or when Pe is greater than threshold Pt1 signifying the upstream pressure is larger, the fuel tank valve A1 is stopped (P11-16).
Regarding claim 3, modified Yoshida teaches the controller is configured to mix oxygen-containing gas into exhaust gas to be discharged from the fuel cell system so as to cause fuel contained in the exhaust gas to have a concentration that falls below a predetermined upper limit release concentration (P12.24; Fig. 1 – S35)
Regarding claim 5, Yoshida teaches the controller 60 is configured to, when activating or stopping the fuel cell stack, output the signal indicating the occurrence of the fuel leakage, or implementing the next process, in a case where the anode internal pressure P2 after the predetermined first period is not lower than the predetermined second anode pressure and an amount of decrease in an internal pressure P1 of the fuel pipe on an upstream side of the fuel stop valve during the predetermined first period is larger than a first permissible decrease amount (P15-20; Fig. 2).
Claims 4 is rejected under 35 U.S.C. 103 as being unpatentable over Yoshida as applied to at least claim 3 above, and further in view of in view of Takahashi (US 20200036021) and Clingerman et al. (US 20210135256).
Regarding claim 4, Yoshida teaches an exhaust gas pipe 33 connected to the anode gas outlet wherein the exhaust fuel valve A5 is provided in the exhaust gas pipe 33 (Fig. 1).
Yoshida is silent in teaching an oxygen tank; an oxygen pipe connecting the fuel cell stack and the oxygen tank; a bypass pipe connecting the oxygen pipe and the exhaust gas pipe; and a regulator provided in the bypass pipe and configured to regulate an amount of oxygen to be sent from the oxygen tank to the exhaust gas pipe through the bypass pipe, wherein the exhaust fuel valve is provided in the exhaust gas pipe, the oxygen-containing gas is supplied to the exhaust gas pipe through the oxygen pipe and the bypass pipe, and the controller is configured to control the regulator to regulate a flow rate of the oxygen-containing gas; however, Takahashi, in a similar field of endeavor, also teaches control of a fuel cell process via input gases (Fig. 1).
Takahashi teaches an oxygen supply source 14; an oxygen pipe 31 connecting the fuel cell stack 11 and the oxygen source; a bypass pipe 41 connecting the oxygen pipe 31 and an exhaust gas pipe 63; and a regulator 36 provided in a bypass pipe 41 and configured to regulate an amount of oxygen to be sent from the oxygen tank to the exhaust gas pipe through the bypass pipe, wherein the exhaust fuel valve is provided in the exhaust gas pipe, the oxygen-containing gas is supplied to the exhaust gas pipe through the oxygen pipe and the bypass pipe, and the controller is configured to control the regulator to regulate a flow rate of the oxygen-containing gas to drive discharge and manage oxidant pressure (P17-20; Fig. 1).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the instant application to have an oxygen pipe connecting the fuel cell stack and the oxygen supply source; a bypass pipe connecting the oxygen pipe and the exhaust gas pipe; and a regulator provided in the bypass pipe and configured to regulate an amount of oxygen to be sent from the oxygen tank to the exhaust gas pipe through the bypass pipe, wherein the exhaust fuel valve is provided in the exhaust gas pipe, the oxygen-containing gas is supplied to the exhaust gas pipe through the oxygen pipe and the bypass pipe, and the controller is configured to control the regulator to regulate a flow rate of the oxygen-containing gas in Yoshida, as taught by Takahashi to further regulate the pressure balance within the fuel cell.
Furthermore, while modified Yoshida in view of Takashi is silent in teaching the oxygen may be in a storage tank, Clingerman, in a similar field of endeavor, teaches where oxygen is scarce, an oxygen tank or of pressurized air, in instances of specific utility, may be used (P34).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the instant application to use an oxygen tank as the oxygen supply source of modified Yoshida in view of Takahashi, as a design choice in scenarios where oxygen or ambient air may be scarce, as taught by Clingerman. It has held that the selection of a known material and/or entity based on its suitability for its intended use supported a prima facie obviousness determination. MPEP 2144.07
Claims 6-7 are rejected under 35 U.S.C. 103 as being unpatentable over Yoshida as applied to at least claim 1 above, and further in view of Yamamori et al. (US 20190148747), Hiroki et al. (JP2021034132A, provided in the IDS dated 5/17/2023), and Shiokawa et al. (US 20160380294 A1).
Regarding claim 6, Yoshida teaches an oxygen pipe connected to the fuel cell stack and oxygen regulators within the oxygen pipe to control the flow of oxygen to be supplied to the cathode of the fuel cell (Fig. 1), but is silent in teaching the exact configurations of claim 6.
However, Yamamori, in a similar field of endeavor, also teaches a fuel cell system regulated with respect to pressure (P17-22; Fig. 1). Yamamori teaches a fuel cell system (10, Fig. 1) comprising: a fuel cell stack 100 (P17; Fig. 1); an oxygen pipe 210 (P21; Fig. 1), see [0021]) connecting the fuel cell stack 100; an oxygen regulator (240 (P22; Fig. 1) disposed in the oxygen pipe 210 (P22; Fig. 1) and configured to regulate a flow rate of oxygen to be supplied from the oxygen tank to a cathode of the fuel cell stack (P22; 240 together with 250 regulates flow rate); an oxygen stop valve 260 disposed in the oxygen pipe 210 (Fig. 1); and a controller 720 wherein the controller 720 is configured to execute (S110-S120, Fig. 2), when activating or stopping the fuel cell stack (P29); a fourth process (S110, Fig. 2) of opening (P24.33; Fig. 2 - S110, when stop instruction turned on (NO), 240 supplies air to 100, 260 and 240 open) the oxygen stop valve 260 and the oxygen regulator 240 (Fig. 1); a fifth process (S120, Fig. 2) of closing (P34; Fig. 2 closes 260, 240 also stops) the oxygen stop valve 260 and the oxygen regulator 240 (Fig. 1).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the instant application to include the configurations of Yamamoto in Yoshida to control and activate the fuel cell.
Modified Yoshida in view of Yamamori is silent in teaching an oxygen tank and an oxygen pipe connecting the oxygen tank; however, Hiroki, in a similar field of endeavor, also teaches a fuel cell system 100. The fuel cell system comprises an oxygen tank 150 (P23; Fig. 1) oxygen pipe 152 (P24; Fig. 1) connecting the oxygen tank 150 (P23; Fig. 1).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the fuel cell system taught by modified Yoshida in view of Yamamori by adding the oxygen tank on the oxygen pipe such that the oxygen pipe is connected to the oxygen tank as taught by Hiroki to store oxygen at predetermined temperature and connects the oxygen tank with the supply port of air electrode.
Modified Yoshida in view of Yamamori and Hiroki is silent in teaching a fifth process of closing the oxygen stop valve and the oxygen regulator when a cathode internal pressure of the fuel cell stack reaches a predetermined first cathode pressure; a sixth process of outputting a signal indicating occurrence of oxygen leakage when the cathode internal pressure after a predetermined period is lower than a predetermined second cathode pressure; however, Shiokawa, in a similar field of endeavor, teaches a fifth process S220 (Fig. 4) of closing the stop valve 53 (Fig. 1) and the regulator 55 when an internal pressure of the fuel cell stack reaches a predetermined first pressure (P55- predetermined pressure);
a sixth process of S230 (Fig. 4) outputting a signal indicating (P56- predetermined display device) occurrence of leakage (P56) when the internal pressure (P55; Fig. 1 by pressure sensor 56) after a predetermined period (P55) is lower than a predetermined second pressure (P55 - specified pressure level).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the fuel cell system taught by modified Yoshida by adding the pressure sensor and the predetermined display device taught by Shiokawa such that the pressure sensor is on the cathode gas supply pipe taught by Yamamori of modified Yoshida for detecting any leakage.
The rationale to support a conclusion that the claim would have been obvious is that a method of enhancing a particular class of devices (methods, or products) has been made part of the ordinary capabilities of one skilled in the art based upon the teaching of such improvement in other situations. One of ordinary skill in the art would have been capable of applying this known method of enhancement to a "base" device (method, or product) in the prior art and the results would have been predictable to one of ordinary skill in the art. MPEP 2143 C
Furthermore, with respect to the above combination of overall element, the rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art
Regarding claim 7, modified Yoshida in view of Yamamori teaches the controller is configured to, when stopping the fuel cell stack, execute the processes with respect to the oxygen/cathode gas before implementing the processes related to the fuel/anode gas to allow an equilibrium to be reached and suppress hydrogen generation pumping, creating a safer gradient of pressure decrease (P34-35.41-50).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the instant application to have the controller of modified Yoshida configured to, when stopping the fuel cell stack, execute the fourth process, the fifth process, and the sixth process before the execution of the first process, the second process, and the third process, to improve safety and allow a gentle decrease in pressure.
Claims 8-9 are rejected over modified Yoshida in view of Yamamori, Hiroki, and Shiokawa, as applied to at least claim 7 above, further in view of Kajiwara (US 20100015482).
Regarding claim 8, modified Yoshida in view of Yamamori, Hiroki, and Shiokawa teaches further comprising:
an oxygen tank valve 250 (Yamamori Fig. 1) attached to the oxygen pipe between the oxygen stop valve 260 (Yamamori Fig. 1) and the oxygen tank 150 (Hiroki Fig. 1); and
an exhaust oxygen valve 290 (Yamamori Fig. 1) configured to stop discharge of gas from a cathode gas outlet of the fuel cell stack 290 (Yamamori P23 - shuts off the cathode off-gas from 100).
Modified Yoshida does not teach wherein the controller is configured to, when stopping the fuel cell stack, before execution of the fourth process, the fifth process, and the sixth process, open the oxygen tank valve, the oxygen stop valve, the oxygen regulator, and the exhaust oxygen valve so as to discharge water remaining in the cathode from the fuel cell stack, and close the oxygen stop valve and the exhaust oxygen valve and, when an internal pressure of the oxygen pipe on an upstream side of the oxygen stop valve reaches an upper limit cathode pressure higher than the predetermined first cathode pressure, close the oxygen tank valve.
However, Shiokawa, in a similar field of endeavor, teaches wherein the controller 20 (Fig. 1) is configured to, when stopping the fuel cell stack S100 (P52; Fig. 2-3 -ordinary stop process) before (P52) execution the second process S220 (Fig. 4), and the third process S230 (Fig. 4), open S103 (P44 -20 opens 32, 34 and 43 in S103) the oxygen stop valve 34 (Fig. 1), the oxygen regulator 32 (Fig. 1), and the exhaust oxygen valve 43 (Fig. 1) so as to discharge water remaining in the cathode from the fuel cell stack (P40; Fig. 3 - cathode drainage process S103) and close (P44 - 20 closes 32 and 43 in cathode sealing process S102; P25 - 34 closed when 32 not supplying air) the oxygen stop valve 34 (Fig. 1) and the exhaust oxygen valve 43 (Fig. 1).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the controller taught by modified Yoshida in view of Shiokawa to perform the cathode drainage process followed by the cathode sealing process as taught by Shiokawa before the fourth, the first process and the sixth process of modified Yoshida in view of Yamamori, Hiroki, in view of Shiokawa, to suppress water in the fuel cell system from being frozen after a stop of the system and to suppress invasion of the air into the fuel cell and thereby suppress deterioration of the catalyst in the fuel cell (Shiokawa;P39.44).
Modified Yoshida in view of Yamamori, Hiroki, and Shiokawa does not teach open the oxygen tank valve, when an internal pressure of the oxygen pipe on an upstream side of the oxygen stop valve reaches an upper limit cathode pressure higher than the predetermined first cathode pressure, close the oxygen tank valve.
Kajiwara teaches wherein the controller 50 (Fig. 1) is configured to, when stopping the fuel cell stack (Fig. 4- pressure control processing), open the tank valve (P62; Fig. 4 - ST13: open valve SV1), an internal pressure of the pipe on an upstream side (P61; Fig. 1- pressure P detected by pressure sensor p2) of the stop valve SV2 (Fig. 1) reaches an upper limit pressure P2 (Fig. 4) higher than (Fig. 5A - P2 > P1) the predetermined first pressure P1 (Fig. 4), close the tank valve (P62; Fig. 4 - ST15: close valve SV1 when P reaches P2 (P < P2 is NO in ST14)).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify fuel cell system and the controller taught by modified Yoshida by adding the pressure sensor taught by Kajiwara on the cathode gas supply pipe and the upstream side of the supply-side on-off valve, configuring the controller to execute the pressure control processing as taught by Kajiwara to secure the pressure of the pipe (Kajiwara; P62).
Regarding claim 9, modified Yoshida in view of Yamamori, Hiroki, Shiokawa, and Kajiwara teaches further comprising an exhaust oxygen pipe 220 (Yamamori; Fig. 1) connected to the cathode gas outlet (Yamamori; P23 - outlet of the cathode) wherein the exhaust oxygen valve 290 is provided in the exhaust oxygen pipe 220 (Yamamori; Fig. 1).
Claim 10 is rejected over modified Yoshida in view of Yamamori, Hiroki, and Shiokawa as applied to at least claim 6 above, and further in view of Yoshida’05 (US 20090239105).
Regarding claim 10, modified Yoshida in view of Yamamori, Hiroki, and Shiokawa teaches wherein the controller 20 (Shiokawa; Fig. 1) is configured to, when activating or stopping the fuel cell stack S230 (Shiokawa; P56; Fig. 4) output the signal indicating (Shiokawa; P56 - predetermined display device) the occurrence of the leakage (Shiokawa; P56 - occurrence of leakage).
Modified Yoshida does not teach in a case where the cathode internal pressure after the predetermined period is not lower than the predetermined second cathode pressure and an amount of decrease in an internal pressure of the oxygen pipe on an upstream side of the oxygen stop valve during the predetermined period is larger than a permissible decrease amount.
Yoshida’05, in a similar field of endeavor, teaches in a case (Fig. 32 - S1013-S1016) where the internal pressure (Fig. 1 - measured by pressure sensor P61) after the predetermined period t4 (P122) is not lower (P122 - P61 higher than P61P (S1015: YES)) than the predetermined second pressure P61P (P122) and an amount of decrease (Fig. 32 - ΔP6, S1014) in an internal pressure (Fig. 1- measured by pressure sensor P6) of the pipe on an upstream side of the stop valve H200 (Fig. 1) during the predetermined period t4, (P122; Fig. 32) is larger than (Fig. 32 - ΔP6 ≥ Pj15, (S1014: YES)) a permissible decrease amount Pj15 (Fig. 32).
It would have been obvious to one of ordinary skill in the art before the effective filling date of the claimed invention to modify the fuel cell system and the controller taught by modified Yoshida by adding the pressure sensor taught by Yoshida’05 on the cathode gas supply pipe and the upstream side of the supply-side on-off valve taught by modified Yoshida, configuring the controller to perform the gas leakage judgment taught by Yoshida’05 to determine if the gas leakage has been generated in the high pressure section (Yoshida’05; P123).
Conclusion
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/Amanda Rosenbaum/Examiner, Art Unit 1752
/Helen Oi K CONLEY/Primary Examiner, Art Unit 1752