Daniel Weldon et al.

Patent Trials and Appeals Board

May 13, 2021

2020003542 (P.T.A.B. May. 13, 2021)

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.
15/059,884 03/03/2016 Daniel Patrick Weldon WELD0100 8940
62124 7590 05/13/2021
QUINN IP Law
21500 Haggerty Road
Suite 300
Northville, MI 48167
EXAMINER
RODRIGUEZ, WILLIAM H
ART UNIT PAPER NUMBER
3741
NOTIFICATION DATE DELIVERY MODE
05/13/2021 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):
USDocketing@quinniplaw.com
adomagala@quinniplaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE

___________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD

___________________

Ex parte DANIEL PATRICK WELDON and KEVIN PATRICK WELDON

____________________

Appeal 2020-003542
Application 15/059,884
Technology Center 3700

____________________

Before JAMESON LEE, MICHAEL R. ZECHER, and
JUSTIN T. ARBES, Administrative Patent Judges.

ZECHER, Administrative Patent Judge.

DECISION ON APPEAL

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I. STATEMENT OF THE CASE
Appellant1 appeals under 35 U.S.C. § 134(a) from the Examiner’s
Final Rejection of claims 10–12, 14, and 20–28. Appeal Br. 2.2,3 Claims 1–
9, 18, and 19 were cancelled. Id. Claims 13, 15–17, and 30 were objected
to as being dependent upon a rejected base claim, but would be allowable if
rewritten in independent form, including all of the limitations of the base
claim and any intervening claim. Appeal Br. 2; Final Act. 14. We have
jurisdiction under 35 U.S.C. § 6.
We affirm.
Appellant’s Invention
Appellant purports to have invented a rocket engine that includes,
among other things, “an electrolyzer capable of operating at high
temperatures in endothermal mode during launch and atmospheric flight.”
Spec. ¶ 22. According to Appellant, “[w]aste heat is utilized to produce
superheated steam to be used for more efficient electrolysis, offering a larger
production capacity of gaseous hydrogen and gaseous oxygen.” Id.

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. According to Appellant, the real parties in interest are the
named inventors—Daniel Weldon and Kevin Weldon. Appeal Br. 2.
2 With the exception of the Claims Appendix, all references to the Appeal
Brief refer to the Appeal Brief filed on July 31, 2019. We refer to the
Claims Appendix filed on September 5, 2019, which was filed in response to
a Notice of Defective Appeal Brief entered on August 15, 2019.
3 Although Appellant initially included dependent claim 29 in the listing of
claims under appeal in the Appeal Brief (Appeal Br. 2), the Examiner
withdrew the rejection of claims 27 and 29 as unpatentable under 35 U.S.C.
§ 103 as being obvious over Taguchi and Grant in the Answer (Ans. 3).
Consequently, dependent claim 29 is no longer subject to a rejection by the
Examiner and, therefore, is no longer under consideration for purposes of
this appeal.
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Figure 1, reproduced below, illustrates an exemplary embodiment of
the rocket engine.

Figure 1, reproduced above, illustrates a rocket engine nozzle that includes
primary combustion chamber 35 and divergent nozzle section 36
downstream from the throat. Spec. ¶ 47. The rocket engine also is
connected to water tank 25, liquid oxygen tank 50, and liquid hydrogen tank
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51. Id. ¶¶ 25, 39, 47. Liquid oxygen and hydrogen from liquid oxygen tank
50 and liquid hydrogen tank 51, respectively, are fed into primary injectors
34 for combustion in primary combustion chamber 35. Id. ¶ 47. Water from
water tank 25 is pumped through helical cooling passages 37 encircling the
rocket engine nozzle to assist with cooling the nozzle during combustion.
Id. ¶ 42. After exiting helical cooling passages 37, the now superheated
steam flows into electrolyzer 30, which, in turn, produces gaseous oxygen
and gaseous hydrogen that flow through conduits 53 and 54 to secondary
injectors 31 for injection into divergent section 36 (i.e., the secondary
combustion zone). Id. ¶¶ 42, 46.
Illustrative Claim
Claims 10, 20, and 27 are independent claims, each of which is
directed to “[a] rocket engine.” Claims Appendix. Claims 11, 12, and 14
directly or indirectly depend from independent claim 10, claims 21–26
directly or indirectly depend from independent claim 20, and claim 28
directly depends from independent claim 27. Independent claim 10 is
illustrative of the disclosed invention and this claim is reproduced below:
10. A rocket engine comprising:
a liquid hydrogen tank, a liquid oxygen tank and water
tank;
an electrolyzer for electrolyzing water supplied from said
water tank into gaseous hydrogen and gaseous oxygen;
a nozzle having a combustion chamber, a throat and a
divergent section;
a primary injector or a plurality of primary injectors in
fluid communication with both said liquid hydrogen tank and
said liquid oxygen tank;
a manifold surrounding a circumference portion of said
divergent section;
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said manifold communicates said gaseous hydrogen and
said gaseous oxygen to secondary injectors;
said electrolyzer in fluid communication with said
manifold.
Claims Appendix.
Prior Art Relied Upon
Inventor4 Patent or Publication No. Relevant Dates
Grant U.S. Patent No. 3,490,235 issued Jan. 20, 1970;
filed Sept. 12, 1967
Grote U.S. Patent Application
Publication No. 2012/0060464
A1
published Mar. 15, 2012;
filed May 26, 2009
Rejection on Appeal
References 35 U.S.C. § Claims Rejected
Grote, Grant 103 10–12, 14, 20–28
Examiner’s Findings and Conclusions
The Examiner finds that Grote’s rocket engine illustrated in Figures 9
and 105 teaches all the limitations of independent claim 10, except “an
electrolyzer for electrolyzing water supplied from said water tank into
gaseous hydrogen and gaseous oxygen.” Final Act. 2–5 (citing Grote ¶ 82,
Figs. 9, 10). The Examiner turns to Grant’s rocket engine that includes
electrolyzer 10 to teach this limitation. Id. at 5–6 (citing Grant, sole Fig.
(element 10)). According to the Examiner, it would have been obvious to a

4 For clarity and ease of reference, we only list the first named inventor.
5 The Examiner treats the various components illustrated in the rocket engine
cooling system illustrated in Figures 9 and 10 as interchangeable. This is
consistent with the corresponding description of Figures 9 and 10 of Grote,
which discusses different aspects of the same “dual-shell implementation” of
the rocket engine cooling system. Grote ¶¶ 134–145.
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person of ordinary skill in the art to add Grant’s electrolyzer 10 to Grote’s
rocket engine cooling system because adding an electrolyzer “is a most
convention technique for generating gaseous propellants in [a] space craft,”
and “[t]he water electrolysis-rocket system constitutes a reaction control
system of high reliability, substantial life-time in orbit, and relatively low
weight.” Id. at 6 (emphasis omitted) (quoting Grant, 1:50–60).
With the exception of the “water pump” recited in each of
independent claims 20 and 27, and the “heat exchanger” only recited in
independent claim 27, the Examiner relies on essentially the same findings
and conclusion to support the obviousness rejection of independent claims
20 and 27 based on the combined teachings of Grote and Grant. Compare
Final Act. 7–11, with id. at 2–6. The Examiner turns to Grote’s disclosure of
maintaining sufficient pressure in the flow of coolant fluids through the use
of pumps to teach the “water pump.” Id. at 7 (citing Grote ¶ 108), 9 (citing
the same). The Examiner turns to the lower section of outer shell 1007 of
the rocket nozzle illustrated in Figures 9 and 10 of Grote to teach the “heat
exchanger.” Id. at 9 (citing Grote, Figs. 9, 10 (outer shell 1007)).
Appellant’s Contentions
Appellant contends that, although Grote discloses a rocket engine
propulsion system that includes nozzle film coolant manifold 1057 that
works in conjunction with injection mechanisms 126 to inject water into the
rocket nozzle to cool the nozzle shell, Grote does not disclose an electrolyzer
for electrolysis of water into gaseous hydrogen and gaseous oxygen as
required by independent claims 10, 20, and 27, much less using gaseous
hydrogen and gaseous oxygen for cooling purposes. Appeal Br. 7–8 (citing
Grote ¶¶ 4, 7, 29, 74, 88, 98, 100, 129). Appellant further contends that,
even though Grant discloses a rocket engine that includes electrolyzer 10 for
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converting water into gaseous hydrogen and gaseous oxygen for propellant
purposes, Grant does not disclose a cooling system, much less a method of
cooling the divergent section of its rocket nozzle. Id. at 8 (citing Grant,
1:31–34, 1:50–60). Appellant asserts that Grant does not teach adding its
electrolyzer 10 immediately adjacent to Grote’s nozzle film coolant
manifold 1057 because the gaseous hydrogen and gaseous oxygen generated
by Grant’s electrolyzer 10 would not function as a coolant. Id. at 8. Instead,
Appellant asserts that the gaseous hydrogen and gaseous oxygen generated
by Grant’s electrolyzer 10 would immediately burn once exposed to the
existing high temperature of the exhaust thrust gases that exist in Grote’s
combustion chamber 106 and, as a result, would further heat the internal
surface of Grote’s rocket nozzle. Id. at 8–9.
In addition, Appellant contends that Grote does not teach the
“secondary injectors” recited in independent claim 10 because, according to
Appellant, injector mechanisms 126 are believed to be one continuous slit
about the inner circumference of Grote’s rocket nozzle. Appeal Br. 9.
Appellant also argues that, even if Grote did include a plurality of secondary
injectors about the inner circumference of Grote’s rocket nozzle, these
injectors would not be adequate to cool the rocket nozzle because such an
arrangement would leave gaps between each secondary injector, resulting in
the uneven distribution of coolant throughout the internal surface of the
rocket nozzle. Id.
II. ISSUES
Based on the record before us, the issues presented are as follows:
1. whether the Examiner presents sufficient evidence to support a
finding that Grant teaches the “electrolyzer,” as recited in independent
claims 10, 20, and 27;
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2. whether the Examiner presents sufficient evidence to support a
finding that Grote teaches the “secondary injectors,” as recited in
independent claim 10; and
3. whether the Examiner presents a sufficient rationale to combine
the teachings of Grote with those of Grant?
III. ANALYSIS
Claims 10, 20, and 27
Based on the record before us, we discern no error in the Examiner’s
obviousness rejection of independent claim 10, which recites, in relevant
part, an “electrolyzer” and “secondary injectors.” We also discern no error
in the Examiner’s obviousness rejection of independent claims 20 and 27,
each of which recites, in relevant part, an “electrolyzer.” We address each
of the issues identified above in turn.
“electrolyzer”
The Examiner finds—and we agree—that Grant’s electrolyzer 10 that
converts water 26 into gaseous hydrogen and gaseous oxygen teaches the
“electrolyzer,” as recited in each of independent claims 10, 20, and 27. Final
Act. 5–8, 10; Grant, 2:33–55, 3:28–32. We do not agree with Appellant’s
assertion that Grant’s electrolyzer 10 only is capable of performing
electrolysis to produce gaseous hydrogen and gaseous oxygen for propellant
purpose—not for coolant purposes. Appeal Br. 8. Although Appellant is
correct that Grant specifically discloses electrolyzer 10 as performing
electrolysis for propellant purposes (Grant, 3:28–32), the Examiner provides
sufficient evidence in response to Appellant’s assertion to demonstrate that a
person of ordinary skill in the art would have understood that the gaseous
hydrogen and gaseous oxygen generated by Grant’s electrolyzer 10 also
could be used for coolant purposes.
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In the Answer, the Examiner states that “gaseous hydrogen and
gaseous oxygen can be and have been used as film coolants in rocket
nozzles,” as evidenced by a NASA article captioned “Hydrogen/Oxygen
Auxiliary Propulsion Technology,” Conference on Advanced Space
Exploration Initiative Technologies (Sept. 4–6, 1991) (“H/O Article”).
Ans. 5. Indeed, the H/O Article states that, when testing “a gaseous-
hydrogen-liquid-oxygen thruster” that uses “the same igniter design and
thermal management scheme as [a] liquid H/O thruster,” “gaseous hydrogen
was used to regeneratively cool the combustion chamber and film cool the
nozzle.” H/O Article, 7; see also id. at Fig 12 (illustrating “[t]hrust chamber
cooling concepts for 6600-N (1500-lbf), gaseous H/O thrusters”). In our
view, the H/O Article presented and developed for the first time in the
Answer constitutes evidence of the general background knowledge of a
person of ordinary skill in the art and, therefore, sufficiently demonstrates
that gaseous hydrogen and gaseous oxygen generated by Grant’s electrolyzer
10 also could be used to film cool Grote’s rocket nozzle. Appellant did not
file a reply brief in response to the Examiner’s reliance on the H/O Article.
“secondary injectors”
The Examiner finds—and we agree—that Grote’s injection
mechanisms 126 for injecting water into the rocket nozzle teaches the
“secondary injectors,” as recited in independent claim 10. Final Act. 5;
Grote ¶¶ 70 (disclosing that “external convective coolant 126 is . . . injected
as a film coolant along the interior wall 110 . . . of the expansion nozzle
108”), 82 (disclosing that “the external convective coolant 126 can be,”
among other things, water). Contrary to Appellant’s assertion, neither the
plain language of independent claim 10 nor the Specification require that the
“secondary injectors” be configured in a specific way. See Appeal Br. 9.
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Instead, all that is required is for the “secondary injectors” to communicate
with the “manifold” and be located downstream from the “primary
injectors.” Claim 10, Spec. ¶ 37. Grote’s injection mechanisms 126 for
injecting water into the rocket nozzle teach the “secondary injectors” recited
in independent claim 10 because they are in communication with nozzle film
coolant manifold 1057 and they are located downstream from main
propellant injector 114. Grote, Fig. 10.
Rationale to Combine
The Examiner provides an annotation version of Figure 9 of Grote’s
rocket nozzle and surrounding components in the Final Action, reproduced
below, that indicates how the Examiner proposes to add Grant’s electrolyzer
10 to Grote’s rocket engine cooling system. Final Act. 4.

The Examiner’s annotated version of Figure 9 of Grote, reproduced above,
illustrates that the Examiner proposes adding Grant’s electrolyzer 10
immediately adjacent to nozzle film coolant manifold 1057 and just below
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coolant check value 944. Id. According to the Examiner, it would have
been obvious to a person of ordinary skill in the art to add Grant’s
electrolyzer 10 to Grote’s rocket engine cooling system in this specific way
because using an electrolyzer “is a most convenient technique for generating
gaseous propellants in [a] space craft,” and “[t]he water electrolysis-rocket
system constitutes a reaction control system of high reliability, substantial
lifetime in orbit, and relatively low weight.” Id. at 6 (quoting Grant, 1:50–
60).
We agree with the Examiner that a person of ordinary skill in the art
would have been motivated to add, and had a reasonable expectation of
success in adding, Grant’s electrolyzer 10 to Grote’s rocket engine cooling
system in the specific location identified in the annotated version of Figure 9
because this configuration still permits Grote’s rocket engine cooling system
to maintain its primary function of cooling the thrust chamber by allowing
the flow of external convection coolant 126 (e.g., water) through gap 1018
between the inner shell 1006 and outer shell 1007. See Grote ¶ 141.
Moreover, in the Examiner’s proposed combination, Grote’s coolant check
value 944 would still keep gap 1018 from being prematurely over
pressurized, while at the same time feeding the remaining water or
superheated steam to the newly added electrolyzer 10, which, in turn,
converts the water or steam to gaseous hydrogen and gaseous oxygen for
injection into the rocket nozzle via existing nozzle film coolant manifold
1057 and injection mechanisms 126. Grote ¶ 140; Grant, 1:50–60; see also
Ans. 4–5 (stating that, in the Examiner’s proposed combination, “the
gaseous hydrogen and gaseous oxygen introduced into Grote’s rocket nozzle
via existing manifold 1057 and secondary injectors (ports/orifices in the
manifold for injecting the fluid) would function as film coolants because
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these gases will be at a much lower temperature than the combustion gases
in the combustion chamber, so any fluid at a lower temperature than the
combustion gases would serve as a coolant/film coolants”).
Based on the record before us, we are not persuaded by Appellant’s
argument that the gaseous hydrogen and gaseous oxygen generated by
Grant’s electrolyzer 10 would not function as a coolant, but instead would
only function to provide additional heat to the internal surface of Grote’s
rocket nozzle. Appeal Br. 9–10. Appellant’s argument is belied by the
evidence of record, which suggests that a person of ordinary skill in the art
would have understood that gaseous hydrogen and gaseous oxygen
generated by Grant’s electrolyzer 10 also could be used to film cool Grote’s
rocket nozzle. H/O Article, 7, Fig. 12.
It follows that the Examiner has not erred in determining that the
combined teachings of Grote and Grant render the subject matter of
independent claims 10, 20, and 27 obvious.
Claim 11, 12, 14, 21–26, and 28
Appellant does not address separately the Examiner’s findings and
conclusions with respect to dependent claims 11, 12, 14, 21–26, and 28. See
Appeal Br. 7–10. We, therefore, group these dependent claims with their
underlying base claim. Consequently, dependent claims 11, 12, and 14 fall
with independent claim 10, dependent claims 21–26 fall with independent
claim 20, and dependent claim 28 falls with independent claim 27. See
37 C.F.R. § 41.37(c)(1)(iv).
IV. CONCLUSION
For the foregoing reasons, the Examiner has not erred in rejecting
claims 10–12, 14, and 20–28 as unpatentable under § 103 as obvious over
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the combined teachings of Grote and Grant. Accordingly, we affirm the
Examiner’s decision to reject these claims.
V. DECISION SUMMARY
In summary:
Claim(s)
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
10–12, 14, 20–
28
103 Grote, Grant 10–12, 14,
20–28

Overall
Outcome
10–12, 14,
20–28

VI. TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED