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 .
Status of Claims
Claims 1, 5 are amended.
Claims 2-4, 6 are cancelled.
Claims 1, 5 are pending.
Response to Amendment
Applicant’s amendments filed on 1/27/2026 have been entered.
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.
Claims 1 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Handa et al (US 2009/0159258 A1) in view of Hotta et al (JP 2008020039A), further in view of Thomas et al (Aircraft anti-icing and de-icing techniques and modeling, Scott K. Thomas, Robert P. Cassoni, and Charles D. MacArthur, Journal of Aircraft 1996 33:5, 841-854) and Singh et al (Dushyant Singh, B. Premachandran, Sangeeta Kohli, Effect of nozzle shape on jet impingement heat transfer from a circular cylinder, International Journal of Thermal Sciences, Volume 96, 2015, Pages 45-69), as evidenced by “Fuel cells” U.S. D.O.E. article (https://www.energy.gov/eere/fuelcells/fuel-cells#:~:text=A%20fuel%20cell%20uses%20the,electricity%2C%20water%2C%20and%20heat., May 2014).
Regarding Claim 1,
Handa teaches a fuel cell (Paragraph [0016]), hydrogen gas stored in a tank (Paragraph [0016]), check valves in inlet and outlet conduits of the hydrogen tank (Paragraph [0022], 30 in, 30 out), o-rings, rubber or polymer seals used in the tank (Paragraph [0017]), a warming device or ring with a fluid conduit that includes an inlet and an outlet (Paragraph [0019]). Handa teaches that the warming system in the boss is fed by a heating energy from a source on board the vehicle which is circulated and the heating energy so received (Paragraph [0018]). Handa also teaches various heat sources in the vehicle systems, such as vehicle system exhaust heat (Figure 8; from the fuel cell), or motor used in the vehicle (Figure 8). These heat sources associated with the vehicle system are operatively interconnected with the inlet and outlet of the fluid conduit employed in the warming ring (Paragraph [0019]).
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Handa does not teach the presence of a flight vehicle, but Handa does support the use of the warming device in environments where low temperature climate conditions are expected (Paragraph [0017]). Such low temperature climate exposures are experienced in flight vehicles.
However, Hotta teaches that the overall configuration of the fuel cell system with the hydrogen valve is applied to fuel cell vehicle, and moving objects such as airplanes (Paragraph [0018]). Hence, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to use the valve and the warming unit from Handa in a flight vehicle per Hotta in order to prevent malfunction of rubber material (used in seals) at low temperatures (Paragraph [0002]). The examiner further notes that the primary reference of Handa also teaches vehicles generically (Paragraph [0002]), and thus, it is further obvious to use the fuel cell of Handa in an aircraft.
Further, Handa does not teach that the exhaust gas from fuel cell is conducted through a pipe that terminates in a nozzle, and the exhaust gas is directed as a jet onto the valve from the nozzle so the exhaust gas hits the valve.
However, Singh teaches that jet impingement heating is widely used in many engineering applications to achieve very high heat transfer rate from a target surface. Jet impingement involves the use of a nozzle directed towards a surface that needs to be either heated or cooled. Some applications of jet impingement are related to anti-icing system in aircrafts. Anti-icing is a process that requires the use of a heated medium in order to raise the temperature of a surface. This can be considered akin to the instant invention wherein the objective is to raise the temperature of the valve and seal by the use of a heated medium.
Further, Thomas teaches the use of hot exhaust gas in aircrafts for the purpose of anti-icing (Page 3, Section B.). Thomas teaches that the waste heat from exhaust gas is diverted from the source by interconnecting ductwork to the interior of the location to be anti-iced. The hot air is then discharged from the ductwork into piccolo tubes or narrow-gap passages to transfer thermal energy to the aircraft. The narrow-gap passages are akin to the use of nozzles that are directed on the surface to be heated.
Hence, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to use a nozzle where the exhaust pipe terminates in order to direct the heat to the valve and stem. A person of ordinary skill in the art would have been motivated to do so since the use of jet impingement for heating aircraft surfaces is known.
Handa does not specifically teach that the exhaust gas continues to be sprayed while the flight vehicle is in flight. However, the combination of Handa, Thomas and Singh does teach that the exhaust gas from a fuel cell is sprayed via nozzle arrangement on the valve in order to de-ice or warm up the valve. A fuel cell powered aircraft will only have the fuel cell in operation when the aircraft needs the power and energy to remain in flight. Hence, the fuel cell will continue to provide power while the flight vehicle is in flight. While the fuel cell is in operation, it is known to generate exhaust gas and waste heat. This is evidenced in fuel cells article from U.S. Department of Energy which states that “Fuel cells work like batteries, but they do not run down or need recharging. They produce electricity and heat as long as fuel is supplied. A fuel cell consists of two electrodes—a negative electrode (or anode) and a positive electrode (or cathode)—sandwiched around an electrolyte. A fuel, such as hydrogen, is fed to the anode, and air is fed to the cathode. In a hydrogen fuel cell, a catalyst at the anode separates hydrogen molecules into protons and electrons, which take different paths to the cathode. The electrons go through an external circuit, creating a flow of electricity. The protons migrate through the electrolyte to the cathode, where they unite with oxygen and the electrons to produce water and heat.” Thus, the examiner contends that it is expected that the heat is being produced as the fuel is supplied, and the exhaust gas continues to be sprayed while the flight vehicle is in flight in order to effectively utilize the waste heat being generated when the aircraft is flying.
Regarding Claim 5,
Handa teaches a flight vehicle with a fuel cell and storage tank, etc. and valve but does not expressly teach the use of air discharged from an air compressor to be used as the waste heat fluid.
However, Hotta teaches an air compressor A3 capable of supplying air as oxidizing gas to a supply port of the fuel cell. Furthermore, Thomas teaches the use of hot bleed air from the high-pressure compressor as the source of heat for thermal anti-icing in aircrafts (Page 3, Section B). Hence, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to use waste heat from an air compressor to heat up the storage tank valve.
Handa does not teach that the exhaust gas from air compressor is directed as a jet onto the valve from the pipe so the exhaust gas hits the valve.
However, Singh teaches that jet impingement heating is widely used in many engineering applications to achieve very high heat transfer rate from a target surface. Jet impingement involves the use of a nozzle directed towards a surface that needs to be either heated or cooled. Some applications of jet impingement are related to anti-icing system in aircrafts. Anti-icing is a process that requires the use of a heated medium in order to raise the temperature of a surface. This can be considered akin to the instant invention wherein the objective is to raise the temperature of the valve and seal by the use of a heated medium.
Further, Thomas teaches the use of hot exhaust gas in aircrafts for the purpose of anti-icing (Page 3, Section B.). Thomas teaches that the waste heat from exhaust gas is diverted from the source by interconnecting ductwork to the interior of the location to be anti-iced. The hot air is then discharged from the ductwork into piccolo tubes or narrow-gap passages to transfer thermal energy to the aircraft. The narrow-gap passages are akin to the use of nozzles that are directed on the surface to be heated.
Hence, it would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to use a nozzle where the exhaust pipe terminates in order to direct the heat to the valve and stem. A person of ordinary skill in the art would have been motivated to do so since the use of jet impingement for heating aircraft surfaces is known in the art.
Handa does not specifically teach that the exhaust gas continues to be sprayed while the flight vehicle is in flight. However, the combination of Handa, Thomas and Singh does teach that the exhaust gas from a fuel cell is sprayed via nozzle arrangement on the valve in order to de-ice or warm up the valve. A fuel cell powered aircraft will only have the fuel cell in operation when the aircraft needs the power and energy to remain in flight. Hence, the fuel cell will continue to provide power while the flight vehicle is in flight. While the fuel cell is in operation it is known to generate exhaust gas and waste heat. This is evidenced in fuel cells article from U.S. Department of Energy which states that “Fuel cells work like batteries, but they do not run down or need recharging. They produce electricity and heat as long as fuel is supplied. A fuel cell consists of two electrodes—a negative electrode (or anode) and a positive electrode (or cathode)—sandwiched around an electrolyte. A fuel, such as hydrogen, is fed to the anode, and air is fed to the cathode. In a hydrogen fuel cell, a catalyst at the anode separates hydrogen molecules into protons and electrons, which take different paths to the cathode. The electrons go through an external circuit, creating a flow of electricity. The protons migrate through the electrolyte to the cathode, where they unite with oxygen and the electrons to produce water and heat.” Thus, the examiner contends that it is expected that the heat is being produced as the fuel is supplied, and the exhaust gas continues to be sprayed while the flight vehicle is in flight in order to effectively utilize the waste heat being generated when the aircraft is flying.
References of Interest
Omori et al (JP2011100646A Machine translation)
Ekkad, S. V., and Singh, P. (April 21, 2021). "A Modern Review on Jet Impingement Heat Transfer Methods." ASME. J. Heat Transfer. June 2021; 143(6): 064001. https://doi.org/10.1115/1.4049496
Rocklin et al (US 20100163677 A1)
Kumar, Ashwani Dutt, Nitesh Awasthi, Mukesh Kumar. (2025). <i>Heat Transfer Enhancement Techniques - Thermal Performance, Optimization and Applications - 1.2.7 Effect of Jet Impingement.</i> John Wiley & Sons. Retrieved from <br>https://app.knovel.com/hotlink/pdf/id:kt0149I674/heat-transfer-enhancement/effect-jet-impingement
Response to Arguments
Applicant's arguments filed 1/27/2026 have been fully considered but they are not persuasive. The arguments are towards the amendments to claims 1 and 5, and the rejection above addresses the new limitation.
Applicant argues that Handa does not mention continuous injection of exhaust gas, and shows circulation of the fluid. Examiner asserts that the rejection of Claim 1 is based on the combination of Handa, Hotta, Singh and Thomas which provides the structure of using exhaust gas for warming the tank valve, and providing a nozzle type arrangement that directs the exhaust gas to the valve. Singh and Thomas provide well known methods of de-icing aircrafts using jet impingement of exhaust gas. Hence, the combination of prior art is proper. Furthermore, Handa states the recirculation of heating fluid, but not the exhaust gas directly. Handa does not limit the flow of the exhaust gas. The “Fuel cell” article cited further provides evidence that the exhaust gas would continuously be sprayed when the flight vehicle is in flight.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/SUHANI JITENDRA PATEL/Examiner, Art Unit 1783
/MARIA V EWALD/Supervisory Patent Examiner, Art Unit 1783