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 the Claims
The status of the claims as filed in the reply dated 4/9/2026 are as follows:
Claims 1 and 11 are amended,
Claims 4, 7-8, 14, and 17-18 are canceled,
Claims 21 and 22 are new,
Claims 1-3, 5-6, 9-13, 15-16, and 19-22 are currently pending.
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, 5-6, 9-13, 15-16, and 19-22 is/are rejected under 35 U.S.C. 103 as being unpatentable over Broeckerhoff et al. (European Patent Publication EP1314166B1, “Broeckerhoff”, previously cited) in view of Lo et al. (U.S. Patent Publication No. 2017/0153067, “Lo”, previously cited).
Regarding claim 1, Broeckerhoff discloses a hydrogen recombiner (fig 1) assembly comprising:
a hydrogen recombiner integrated with a passive heat sink (7), the passive heat sink comprising a heat transfer working fluid (¶0020), and the hydrogen recombiner comprising a catalyst (8, ¶0021); and
wherein the hydrogen recombiner is configured to convert leaked hydrogen to water vapor (¶0002-0003),
wherein the passive heat sink (7) comprises an evacuated metallic cylindrical tube (as evident in fig 2) that is sealed and filled with the heat transfer working fluid (¶0020),
wherein the heat transfer working fluid configured to flow in an annular space of the passive heat sink (as evident in fig 2).
However, Broeckeroff does not explicitly disclose wherein an inner wall of the passive heat sink includes a capillary porous wick lining, the capillary porous wick lining configured to enable transport of heat along a length of the passive heat sink. Lo, however, discloses a heat pipe (fig 6) wherein the heat transfer working fluid is water (¶0041), wherein the passive heat sink comprises aluminum (¶0041), wherein the passive heat sink comprises a metal tube (¶0041), and wherein an inner wall of the passive heat sink includes a capillary porous wick lining (100, ¶0041), the capillary porous wick lining configured to enable transport of heat along a length of the passive heat sink (¶0041). Lo teaches that these configurations improve heat transfer capacity of the heat pipe (¶0043). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Broeckerhoff to provide the heat pipe configuration of Lo for the passive heat sink in order to improve heat exchange capacity.
Regarding claim 2, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the hydrogen recombiner is a flameless hydrogen recombiner (as evident in fig 1).
Regarding claim 3, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the catalyst comprises a platinum catalyst (¶0005).
Regarding claim 5, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the heat transfer working fluid is water (such as taught by Lo).
Regarding claim 6, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the passive heat sink comprises aluminum (such as taught by Lo).
Regarding claim 9, the combination of Broeckerhoff and Lo discloses all previous claim limitations. wherein the hydrogen recombiner assembly is self-regulating and gravity-independent (at least in the passive heat sink which uses capillary force).
Regarding claim 10, the limitation of the hydrogen recombiner assembly is positioned inside a spacecraft is considered an intended use limitation. A recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus satisfying the structural limitations of the claims, as is the case here.
Regarding claim 11, Broeckerhoff discloses a method for operating a hydrogen recombiner comprising: integrating a hydrogen recombiner (fig 1) with a passive heat sink (7), the passive heat sink comprising a heat transfer working fluid (¶0020), and the hydrogen recombiner comprising a catalyst (8, ¶0021); and utilizing the hydrogen recombiner to convert leaked hydrogen to water vapor (¶0002-0003), wherein the passive heat sink (7) comprises an evacuated metallic cylindrical tube (as evident in fig 2) that is sealed and filled with the heat transfer working fluid (¶0020),
wherein the heat transfer working fluid configured to flow in an annular space of the passive heat sink (as evident in fig 2).
However, Broeckeroff does not explicitly disclose wherein an inner wall of the passive heat sink includes a capillary porous wick lining, the capillary porous wick lining configured to enable transport of heat along a length of the passive heat sink. Lo, however, discloses a heat pipe (fig 6) wherein the heat transfer working fluid is water (¶0041),wherein the passive heat sink comprises aluminum (¶0041), wherein the passive heat sink comprises a metal tube (¶0041), and wherein an inner wall of the passive heat sink includes a capillary porous wick lining (100, ¶0041), the capillary porous wick lining configured to enable transport of heat along a length of the passive heat sink (¶0041). Lo teaches that these configurations improve heat transfer capacity of the heat pipe (¶0043). It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention for Broeckerhoff to provide the heat pipe configuration of Lo for the passive heat sink in order to improve heat exchange capacity.
Regarding claim 12, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the hydrogen recombiner is a flameless hydrogen recombiner (as evident in fig 1).
Regarding claim 13, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the catalyst comprises a platinum catalyst (¶0005).
Regarding claim 15, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the heat transfer working fluid is water (such as taught by Lo).
Regarding claim 16, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the passive heat sink
Regarding claim 19, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckerhoff further discloses wherein the hydrogen recombiner assembly is self-regulating and gravity-independent (at least in the passive heat sink which uses capillary force).
Regarding claim 20, the limitation of the hydrogen recombiner assembly is positioned inside a spacecraft is considered an intended use limitation. A recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus satisfying the structural limitations of the claims, as is the case here.
Regarding claim 21, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckeroff further discloses wherein the heat transfer working fluid is configured to absorb heat released from the hydrogen recombiner and vaporize to form the water vapor, thereby forcing the water vapor to flow axially upward in the heat sink toward a passive heat sink condenser region where heat is rejected via condensation of the working fluid (such as taught by Lo, ¶0004), and
wherein the working fluid is configured to condense from the water vapor to a liquid releasing heat through the metal casing of assembly (such as taught by Lo, ¶0004), and
wherein the porous wick liner is configured to carry the condensed heat transfer working fluid back to the hydrogen recombiner via capillary surface tension pumping of wick lining (such as taught by Lo, ¶0004).
Regarding claim 22, the combination of Broeckerhoff and Lo discloses all previous claim limitations. Broeckeroff further discloses wherein the heat transfer working fluid is configured to absorb heat released from the hydrogen recombiner and vaporize to form the water vapor, thereby forcing the water vapor to flow axially upward in the heat sink toward a passive heat sink condenser region where heat is rejected via condensation of the working fluid (such as taught by Lo, ¶0004), and
wherein the working fluid is configured to condense from the water vapor to a liquid releasing heat through the metal casing of assembly (such as taught by Lo, ¶0004), and
wherein the porous wick liner is configured to carry the condensed heat transfer working fluid back to the hydrogen recombiner via capillary surface tension pumping of wick lining (such as taught by Lo, ¶0004).
Response to Arguments
Applicant's arguments filed 4/9/2026 have been fully considered but they are not persuasive.
Applicant argues (pages 5-7) that Broeckerhoff does not teach the limitations of the passive heat sink as now required by the amendment of the independent claims. However, Lo is being relied upon to teach these limitations.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to HARRY E ARANT whose telephone number is (571)272-1105. The examiner can normally be reached Monday-Friday 10-6 ET.
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/HARRY E ARANT/Primary Examiner, Art Unit 3763
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