DETAILED ACTION
Response to Amendment
The Amendment filed November 14, 2025 has been entered. Claims 1, 2, 4 – 7, 9, 11, 12, 15 and 17 – 26 are pending in the application with claims 3, 8, 10, 13, 14 and 16 being cancelled and claims 20 – 26 being newly added. The amendment to the claims has overcome some of the 35 USC 112 rejections set forth in the last Non-Final Action mailed August 14, 2025.
Claim Objections
Claims 4 – 7 and 17 – 26 are objected to because of the following informalities:
Claim 17, lines 9-10: “a first end of the elongated piston” should read --the first end of the elongated piston--.
Claim 17, line 10: “a second end of the elongated piston” should read --the second end of the elongated piston--.
Claim 20, last line: “the intermediate fluid seal the pumped fluid seal” should read --the intermediate fluid seal, the pumped fluid seal--.
Claims 22 – 26 are objected to for being dependent on claim 17.
Claims 4 – 7, 18, 19 and 21 are objected to for being dependent on claim 20.
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.
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.
Claims 1, 2 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Noble et al. (US 2005/0086949 – herein after Noble; cited by applicant on IDS dated 07/21/2023) in view of Gustafson, Keith W (US 4,608,831 – herein after Gustafson).
In reference to claim 1, Noble teaches a pump for pumping a cryogenic liquid (cryogenic fluid, see ¶20) comprising:
a pump housing (see fig. 4: 42, 84, 20) defining an elongated cylinder (42+85+20);
an elongated piston (38+80+ unlabeled head within 20 – herein after referred as 80) slidably positioned within the elongated cylinder so that an intermediate fluid chamber (chamber inside the drive part 20) that is configured to receive an intermediate fluid (hydraulic fluid as per claim 38) is defined within the elongated cylinder (within component 20 of the asserted cylinder) adjacent to a first end (left end, in view of fig. 4) of the elongated piston (80) and a fluid pumping chamber (40) is defined within the elongated cylinder (within component 42 of the asserted cylinder) adjacent to a second end (right end, in view of fig. 4) of the elongated piston (80), the fluid pumping chamber (40) including an inlet (34) and an outlet (not shown in fig. 4 but present as per disclosure in ¶54), and wherein the elongated piston moves between a top dead center position (in view of fig. 4: top dead center position = left end position of the piston 80) and a bottom dead center position (in view of fig. 4: bottom dead center position = right end position of the piston 80);
a sump (cryogen space 88, see fig. 1) within which the pump housing (42, 84, 20) is positioned, the sump (88) configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet (34) of the fluid pumping chamber for pumping (see fig. 1);
a sump jacket (formed by walls 91+13, see ¶48 and fig. 1/5) surrounding the sump (88) so that a sump insulation space (17) is defined therebetween wherein the sump insulation space includes vacuum insulation (“17” is an insulation space; see ¶25: “The insulation space may be a vacuum space”); and
a pump jacket (formed by wall 92, see fig. 1/5) surrounding (in partial manner) the pump housing (42, 84, 20) so that a pump insulation space (94) is defined therebetween wherein the pump insulation space includes vacuum insulation (“94” is an insulation space; see ¶83: “… insulated space 94, which may contain suitable insulating material and/or a vacuum space…”).
Noble remains silent on the pump further comprising: a neck jacket connecting the sump jacket to the pump jacket to suspend the pump jacket within the sump, wherein the neck jacket includes a neck jacket insulation space with vacuum insulation that interconnects the vacuum insulation of the sump insulation space with the vacuum insulation of the pump insulation.
However, Gustafson teaches a known use of a neck jacket for suspending objects (in Gustafon’s case, vessel/wall 14) in cryogenic container.
Since applicant in the instant application has not disclosed any criticality associated with suspending the pump jacket by use of the neck jacket, it would have been obvious to the person of ordinary skill in the art to provide a neck jacket as taught by Gustafson for connecting the sump jacket to the pump jacket to suspend the pump jacket within the sump in Noble’s pump as a matter of design choice. It is to be that Noble’s pump jacket is suspended in Noble’s pump and Noble teaches the vacuum insulation (17) of the sump insulation space being in communication with the vacuum insulation (94) of the pump insulation space [in view of disclosure in ¶83], and thus, in the modified pump of Noble, one of ordinary skill in the art would provide the neck jacket that includes a neck jacket insulation space with vacuum insulation that interconnects the vacuum insulation of the sump insulation space with the vacuum insulation of the pump insulation so that the Noble’s teaching remains uncompromised.
In reference to claim 2, Noble teaches the pump of claim 1, further comprising a drive system for cyclically providing the intermediate fluid to the intermediate fluid chamber so that the elongated piston is actuated to pump the cryogenic liquid from the fluid pumping chamber (see claim 38: there exists “a drive system” that provides hydraulic fluid to drive unit 20 for actuation of the piston to pump the cryogenic liquid).
In reference to claim 15, Noble teaches the pump of claim 1, wherein a bottom end (in view of fig. 1: “bottom end of the pump jacket” = right end) of the pump jacket (92 that surrounds housing component 84) is generally coplanar with the second end of the elongated piston (right end of the piston 80, in view of figs. 1/4) when the elongated piston is in the top dead center position [both of the claimed ends are in plane that is into and out of the page; i.e. in a cross-section view of the pump (seen in fig. 1 or fig. 4), when the elongated piston is at the top dead center position, it is evident from fig. 1/4 that the right end of the piston (for instance, right end of component 38) is a bit distant from right end of pump jacket 92; however (in view of fig. 1), the second/right end of the piston is considered to be closer to the bottom/right end of the pump jacket and thus, the second end of the piston is considered to be “generally coplanar” with the second end of the elongated piston].
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Noble in view of Gustafson and Rafalski, Jr (US 2009/0064672 – herein after Rafalski).
Noble teaches the pump of claim 1, wherein (as discussed above in claim 1) the intermediate fluid (hydraulic fluid) is used.
Noble remains silent on the pump, wherein the intermediate fluid is “propane or 1-butene”.
However, Rafalksi teaches (see ¶14) a use of “propane” as a compressed fluid for driving a fluid motor.
It would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to substitute the hydraulic fluid in Noble’s pump for “propane” as taught by Rafalksi in order to obtain the predictable result of pressurized fluid being applied to the hydraulic motor for reciprocating the pump piston in order to pump the desired fluid. KSR Int’l v. Teleflex Inc., 127 S. Ct. 1727, 1740-41, 82 USPQ2d 1385, 1396 (2007)
Claims 11 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Noble in view of Gustafson and Drouvot Philippe (CH703376 – herein after Drouvot).
Noble teaches the pump of claim 1 with the elongated piston.
Noble does not teach the pump, wherein the elongated piston includes a polytetrafluoroethylene coating that is molded to provide circumferential seals, as in claim 11; and wherein the elongated piston includes a core upon which the polytetrafluoroethylene coating is placed, and wherein the core includes a cavity, as in claim 12.
However, Drouvot teaches a piston pump in cryogenic environment, wherein the elongated piston (4) includes a polytetrafluoroethylene coating (coating in the form of PTFE/bronze rings 43,44,45; see ¶18 of translation) that is molded to provide circumferential seals (rings provide sealing in circumferential direction) {with respect to feature “a polytetrafluoroethylene coating that is molded”: In accordance to MPEP 2113, the method of forming the device (in this PTFE coating “that is molded”) is not germane to the issue of patentability of the device itself. Therefore, this limitation has not been given patentable weight}, as in claim 11; and wherein the elongated piston (4) includes a core (body) upon which the polytetrafluoroethylene coating (coating in the form of PTFE/bronze rings 43,44,45) is placed, and wherein the core includes a cavity (groove 42), as in claim 12.
Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the piston head in the pumping chamber of Noble’s pump for providing sealing features as taught by Drouvot for the purpose of creating an effective seal, as recognized by Drouvot (see ¶18, lines 193-194 of translation).
Claims 1, 2 and 18 – 21 are rejected under 35 U.S.C. 103 as being unpatentable over Kroeger et al. (US 2016/0208793 – herein after Kroeger) in view of Noble et al. (US 2005/0086949 – herein after Noble; cited by applicant on IDS dated 07/21/2023) and further in view of Gustafson, Keith W (US 4,608,831 – herein after Gustafson).
In reference to claim 1, Kroeger teaches a pump (see fig. 5: cryogenic pump 118) for pumping a cryogenic liquid (cryogenic liquid fuel; see ¶1) comprising:
a pump housing defining an elongated cylinder (see fig. 5: exterior structure of cryogenic pump 118);
an elongated piston (see fig. 5: 152+162+154) slidably positioned within the elongated cylinder so that an intermediate fluid chamber (150) that is configured to receive an intermediate fluid (hydraulic fluid) is defined within the elongated cylinder adjacent to a first end (first end of component 152) of the elongated piston (152+162+154) and a fluid pumping chamber (156) is defined within the elongated cylinder adjacent to a second end (second end of component 154) of the elongated piston (152+162+154), the fluid pumping chamber including an inlet (158; see fig. 5 and ¶29) and an outlet (160; see fig. 5 and ¶29), wherein (in view of fig. 5) the elongated piston moves between a top dead center position and a bottom dead center position.
Kroeger remains silent on the pump further comprising “a sump within which the pump housing is positioned, the sump configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet of the fluid pumping chamber for pumping; a sump jacket surrounding the sump so that a sump insulation space is defined therebetween wherein the sump insulation space includes vacuum insulation; a pump jacket surrounding the pump housing so that a pump insulation space is defined therebetween wherein the pump insulation space include vacuum insulation; and a neck jacket connecting the sump jacket to the pump jacket to suspend the pump jacket within the sump, wherein the neck jacket includes a neck jacket insulation space with vacuum insulation that interconnects the vacuum insulation of the sump insulation space with the vacuum insulation of the pump insulation space”.
However, Noble teaches a similar cryogenic pump comprising: a sump (cryogen space 88, see fig. 1) within which the pump housing (42, 84, 20) is positioned, the sump (88) configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet (34) of the fluid pumping chamber for pumping (see fig. 1); a sump jacket (formed by walls 91+13, see ¶48 and fig. 1/5) surrounding the sump (88) so that a sump insulation space (17) is defined therebetween wherein the sump insulation space includes vacuum insulation (“17” is an insulation space; see ¶25: “The insulation space may be a vacuum space”); and a pump jacket (formed by wall 92, see fig. 1/5) surrounding (in partial manner) the pump housing (42, 84, 20) so that a pump insulation space (94) is defined therebetween wherein the pump insulation space includes vacuum insulation (“94” is an insulation space; see ¶83: “… insulated space 94, which may contain suitable insulating material and/or a vacuum space…”).
It would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the Kroeger’s pump to comprise a sump within which the pump housing is positioned, the sump configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet of the fluid pumping chamber for pumping; a sump jacket surrounding the sump so that a sump insulation space is defined therebetween wherein the sump insulation space includes vacuum insulation; and a pump jacket surrounding said pump housing so that a pump insulation space is defined therebetween, as taught by Noble, for the purpose of providing the benefits of Kroeger’s pump to submerged pumping applications and providing the efficiency advantages of direct immersion provided by Noble to Kroeger’s pump.
Noble further remains silent on the pump further comprising: a neck jacket connecting the sump jacket to the pump jacket to suspend the pump jacket within the sump, wherein the neck jacket includes a neck jacket insulation space with vacuum insulation that interconnects the vacuum insulation of the sump insulation space with the vacuum insulation of the pump insulation.
However, Gustafson teaches a known use of a neck jacket for suspending objects (in Gustafon’s case, vessel/wall 14) in cryogenic container.
Since applicant in the instant application has not disclosed any criticality associated with suspending the pump jacket by use of the neck jacket, it would have been obvious to the person of ordinary skill in the art to provide a neck jacket as taught by Gustafson for connecting the sump jacket to the pump jacket to suspend the pump jacket within the sump in the modified Kroeger’s pump as a matter of design choice. It is to be that Noble’s pump jacket is suspended in Noble’s pump and Noble teaches the vacuum insulation (17) of the sump insulation space being in communication with the vacuum insulation (94) of the pump insulation space [in view of disclosure in ¶83], and thus, in the modified pump of Kroeger, one of ordinary skill in the art would provide the neck jacket that includes a neck jacket insulation space with vacuum insulation that interconnects the vacuum insulation of the sump insulation space with the vacuum insulation of the pump insulation so that the Noble’s teaching remains uncompromised.
In reference to claim 2, Kroeger, as modified, teaches the pump (see Kroeger), further comprising a drive system (see fig. 1: combination of oil reservoir 128, pump 126, accumulator 132, valves 122-124) for cyclically providing the intermediate fluid to the intermediate fluid chamber (150, see fig. 5) so that the elongated piston is actuated to pump the cryogenic liquid from the fluid pumping chamber (see ¶22).
In reference to claim 20, Kroeger, as modified, teaches the pump (see Kroeger), wherein the pump housing (see fig. 5: exterior structure of cryogenic pump 118) having an inner surface, wherein the elongated piston has an intermediate fluid seal (seals of the first piston 152; see ¶31) at the first end of the elongated piston, and a pumped fluid seal (seals of the second piston 154; see ¶31) at the second end of the elongated piston; and wherein the pump further comprises: an annular differential pressure space (see fig. 5: differential pressure space located between 152, 154 and surrounding shaft 162; also labeled “d.p.s.” in fig. A below) defined between a sidewall of the elongated piston, the intermediate fluid seal, the pumped fluid seal, and the inner surface of the pump housing.
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Fig. A: Edited fig. 5 of Kroeger to show claim interpretation.
In reference to claim 21, Kroeger, as modified, teaches the pump (see Kroeger), wherein the inner surface of the pump housing is subdivided into three sections, a first section (see fig. A above: labeled “s1”) which is selectively included as part of the intermediate fluid chamber (150) as the elongated piston moves between the top dead center position and the bottom dead center position, a second section (see fig. A above: labeled “s2”) which is selectively included as part of the fluid pumping chamber (156) as the elongated piston moves between the top dead center position and the bottom dead center position, and a third section (see fig. A above: labeled “s3”), which is distinct from the first section and the second section, that is positioned between and is adjacent to each of the first section and the second section.
In reference to claim 18, Kroeger, as modified, teaches the pump (see Kroeger), wherein a heat transfer path (route through which heat is transferred from one part of a system to another; labeled “h.t.p.” in fig. A above) is associated with the third section of the inner surface of the pump housing (path shown as h.t.p. is considered to be “a heat transfer path” in view of temperature difference between hydraulic fluid flowing into 150/“d.p.s.” and cryogenic fluid flowing into 166/156), which is not selectively included as part of either the intermediate fluid chamber (150) or the fluid pumping chamber (156) as the elongated piston moves between the top dead center position and the bottom dead center position.
In reference to claim 19, Kroeger, as modified, teaches the pump (see Kroeger), wherein the third section (see fig. A above: labeled “s3”) of the inner surface is part of the annular differential pressure space (labeled “d.p.s.” in fig. A above) as the elongated piston moves between the top dead center position and the bottom dead center position.
Claims 4 – 7 are rejected under 35 U.S.C. 103 as being unpatentable over Kroeger in view of Noble and further in view of Gustafson and Pierce et al. (US 5,355,679 – herein after Pierce).
In reference to claim 4, Kroeger teaches the pump, wherein the heat transfer path (“h.t.p.” in fig. A above) has a heat transfer path length, which corresponds to a difference between a length of the elongated piston (152+162+154) and a stroke length of the elongated piston between top dead center and bottom dead center positions (in view of fig. A above: length as well as a stroke length {constituted by distance travelled by component 154 within the cylinder} of the asserted elongated piston is evident).
Kroeger remains silent on the pump wherein the difference “is six inches or more”.
However, Pierce teaches an expansion engine (10) submerged in a cryogenic environment (see fig. 1 and col. 3, lines 17-34). Pierce teaches: (see col. 10, lines 39-44) “As well the present invention is scaleable to achieve a wide range of different capacities for different gases. That is, without redesigning the essential structural features, the components may be sized as necessary to achieve desired capacities, or the piston stroke length or piston diameter may be changed”. Thus, Pierce discloses that the length of a piston (a component in the engine) and piston stroke length can be changed to achieve desired pumping capacities.
Pierce demonstrates that the difference is a result effective variable, wherein the difference directly affects the “pumping capacity” in the reciprocating pump/engine. Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to have the difference in the modified Kroeger’s pump “six inches or more” since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Further, applicant places no criticality on the claimed range, indicating simply (see ¶59 of the pg. pub of the instant application) “As an example only, the piston length 359 (L) may be 30″ while the stroke length 357 (I) may be 20″, which per the above equation gives a heat transfer path length 360 (P) of ten inches. In the illustrated embodiment, the heat transfer path length 360 (P) is preferably approximately six inches or more. A heat transfer path length 360 (P) of approximately twelve inches or more would be even more beneficial”.
In reference to claim 5, Kroeger teaches the pump, wherein there exists a ratio of a diameter of the elongated cylinder to a longitudinal length of the elongated cylinder.
Kroeger remains silent on the pump wherein the ratio “is 8% or less”.
It is well-known in the art that sizing of a pump cylinder in a piston pump is dependent on various factors, such as but not limited to, a sizing of the piston (axial length of the piston and/or diameter of the piston). Pierce further teaches an expansion engine (10) submerged in a cryogenic environment (see fig. 1 and col. 3, lines 17-34). Pierce teaches: (see col. 10, lines 39-44) “As well the present invention is scaleable to achieve a wide range of different capacities for different gases. That is, without redesigning the essential structural features, the components may be sized as necessary to achieve desired capacities, or the piston stroke length or piston diameter may be changed”. Thus, Pierce discloses that sizing of a piston (a component in the engine) can be changed to achieve desired pumping capacities.
As demonstrated above, that the ratio is a result effective variable, wherein the ratio directly affects the “pumping capacity” and/or “sizing of the piston” in the reciprocating pump/engine. Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to have the ratio in the modified Kroeger’s pump “8% or less” since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Further, applicant places no criticality on the claimed range, indicating simply (see ¶61-¶62 of the pg. pub of the instant application) “Non-limiting examples of assembly and dimensions of the components of pump 310 of FIGS. 4A and 4B are presented in FIGS. 5-9. With reference to FIG. 5, piston 322 may be cylindrical with elliptical end caps 362 on each end and have a longitudinal length or height 364 of 30 inches. Pump housing 320 may be tube-shaped with a pump housing cylinder (323) longitudinal length or height 366 of approximately 49 inches. The diameter 368 of cylinder 323 may be approximately 4 inches. As a result, the ratio of the pump housing cylinder diameter to the length of the pump housing cylinder is approximately 8%.”.
In reference to claim 6, Kroeger teaches the pump, wherein the heat transfer path (“h.t.p.” in fig. A above) has a heat transfer path length, which corresponds to a difference between a length of the elongated piston (152+162+154) and a stroke length of the elongated piston between top dead center and bottom dead center positions (in view of fig. A above: length as well as a stroke length {constituted by distance travelled by component 154 within the cylinder} of the asserted elongated piston is evident).
Kroeger remains silent on the pump wherein the difference “is twelve inches or more”.
However, Pierce teaches an expansion engine (10) submerged in a cryogenic environment (see fig. 1 and col. 3, lines 17-34). Pierce teaches: (see col. 10, lines 39-44) “As well the present invention is scaleable to achieve a wide range of different capacities for different gases. That is, without redesigning the essential structural features, the components may be sized as necessary to achieve desired capacities, or the piston stroke length or piston diameter may be changed”. Thus, Pierce discloses that the length of a piston (a component in the engine) and piston stroke length can be changed to achieve desired pumping capacities.
Pierce demonstrates that the difference is a result effective variable, wherein the difference directly affects the “pumping capacity” in the reciprocating pump/engine. Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to have the difference in the modified Kroeger’s pump “twelve inches or more” since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Further, applicant places no criticality on the claimed range, indicating simply (see ¶59 of the pg. pub of the instant application) “As an example only, the piston length 359 (L) may be 30″ while the stroke length 357 (I) may be 20″, which per the above equation gives a heat transfer path length 360 (P) of ten inches. In the illustrated embodiment, the heat transfer path length 360 (P) is preferably approximately six inches or more. A heat transfer path length 360 (P) of approximately twelve inches or more would be even more beneficial”.
In reference to claim 7, Kroeger teaches the pump, wherein there exists a ratio of a diameter of the elongated cylinder to a longitudinal length of the elongated cylinder.
Kroeger remains silent on the pump wherein the ratio “is 8% or less”.
It is well-known in the art that sizing of a pump cylinder in a piston pump is dependent on various factors, such as but not limited to, a sizing of the piston (axial length of the piston and/or diameter of the piston). Pierce further teaches an expansion engine (10) submerged in a cryogenic environment (see fig. 1 and col. 3, lines 17-34). Pierce teaches: (see col. 10, lines 39-44) “As well the present invention is scaleable to achieve a wide range of different capacities for different gases. That is, without redesigning the essential structural features, the components may be sized as necessary to achieve desired capacities, or the piston stroke length or piston diameter may be changed”. Thus, Pierce discloses that sizing of a piston (a component in the engine) can be changed to achieve desired pumping capacities.
As demonstrated above, that the ratio is a result effective variable, wherein the ratio directly affects the “pumping capacity” and/or “sizing of the piston” in the reciprocating pump/engine. Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to have the ratio in the modified Kroeger’s pump “8% or less” since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Further, applicant places no criticality on the claimed range, indicating simply (see ¶61-¶62 of the pg. pub of the instant application) “Non-limiting examples of assembly and dimensions of the components of pump 310 of FIGS. 4A and 4B are presented in FIGS. 5-9. With reference to FIG. 5, piston 322 may be cylindrical with elliptical end caps 362 on each end and have a longitudinal length or height 364 of 30 inches. Pump housing 320 may be tube-shaped with a pump housing cylinder (323) longitudinal length or height 366 of approximately 49 inches. The diameter 368 of cylinder 323 may be approximately 4 inches. As a result, the ratio of the pump housing cylinder diameter to the length of the pump housing cylinder is approximately 8%.”.
Claims 17 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Hartnett et al. (US 2018/0073494 – herein after Hartnett) in view of Durand, Fabien (FR 2904401A1 – herein after Durand) and Noble et al. (US 2005/0086949 – herein after Noble; cited by applicant on IDS dated 07/21/2023).
In reference to claim 17, Hartnett teaches a pump (300/301; see figs. 2, 3 and 6) [note: the embodiment of pump system 130 shown in fig. 6 has pump 301; this pump 301 is a reciprocating-piston, positive displacement pump, as per disclosure in ¶37, actuated by hydraulic circuit 500; the cross-section of the pump 301 is not shown, however, one of ordinary skill in the art would understand that this pump 301 is similar to pump 300 shown in embodiment seen in figs. 2-3 which, as per disclosure in ¶29, is driven by known hydraulically actuated mechanism; thus, the rejection below references figs. 2, 3, 6] for pumping a cryogenic liquid (as discussed in abstract) comprising:
a pump housing (casing seen in fig. 2) defining an elongated cylinder (330);
an elongated piston (310) slidably positioned within the elongated cylinder so that an intermediate fluid chamber (chamber on left side of the piston, see fig. 2) that is configured to receive an intermediate fluid (hydraulic fluid) is defined within the elongated cylinder (330) adjacent to a first end (left end, see fig. 2) of the elongated piston (310) and a fluid pumping chamber (chamber on right side of the piston, see fig. 2) is defined within the elongated cylinder (330) adjacent to a second end (right end, see fig. 2) of the elongated piston (310), the fluid pumping chamber including an inlet (345, see fig. 2) and an outlet (not labeled, but is evident from fig. 2), wherein (in view of fig. 2) the elongated piston moves between a top dead center position (position of piston seen in fig. 2) and a bottom dead center position (position of piston seen in fig. 3).
Hartnett remains silent on the pump having the elongated piston “wherein the first end of the elongated piston has a first elliptical end cap and the second end of the elongated piston has a second elliptical end cap, and between the first elliptical end cap and the second elliptical end cap of the elongated piston, the elongated piston has a consistent cross-section”.
However, Durand teaches a pump (see figs. 1-2d and page 5 of translation, last paragraph) wherein the first end (top end) of the elongated piston (3) has a first elliptical end cap (hemispherical end) and the second end (bottom end) of the elongated piston (3) has a second elliptical end cap (hemispherical end), and between the first elliptical end cap and the second elliptical end cap of the elongated piston, the elongated piston has a consistent cross-section (as evident from figs. 1-2d).
Since applicant in the instant application has not disclosed any criticality associated for use of the piston with “elliptical end caps”, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to use elongated cylinder and elongated piston with elliptical end caps as taught by Durand in the pump of Hartnett as a matter of design choice since such a modification would have involved a change in shape of the piston and ends of the cylinder in order to obtain advantages such as minimal dead space during piston’s stroke changeover, improved centering and reduced edge wear.
Hartnett remains silent on the pump further comprising “a sump within which the pump housing is positioned, the sump configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet of the fluid pumping chamber for pumping; a sump jacket surrounding the sump so that a sump insulation space is defined therebetween wherein the sump insulation space includes vacuum insulation; and a pump jacket surrounding the pump housing so that a pump insulation space is defined therebetween”.
However, Noble teaches a similar cryogenic pump comprising: a sump (cryogen space 88, see fig. 1) within which the pump housing (42, 84, 20) is positioned, the sump (88) configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet (34) of the fluid pumping chamber for pumping (see fig. 1); a sump jacket (formed by walls 91+13, see ¶48 and fig. 1/5) surrounding the sump (88) so that a sump insulation space (17) is defined therebetween wherein the sump insulation space includes vacuum insulation (“17” is an insulation space; see ¶25: “The insulation space may be a vacuum space”); and a pump jacket (formed by wall 92, see fig. 1/5) surrounding (in partial manner) the pump housing (42, 84, 20) so that a pump insulation space (94) is defined therebetween.
It would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the Hartnett’s pump to comprise a sump within which the pump housing is positioned, the sump configured to receive and submerge a portion of the pump housing within the cryogenic liquid and to provide the cryogenic liquid to the inlet of the fluid pumping chamber for pumping; a sump jacket surrounding the sump so that a sump insulation space is defined therebetween wherein the sump insulation space includes vacuum insulation; and a pump jacket surrounding said pump housing so that a pump insulation space is defined therebetween, as taught by Noble, for the purpose of providing the benefits of Hartnett’s pump to submerged pumping applications and providing the efficiency advantages of direct immersion provided by Noble to Hartnett’s pump.
In reference to claim 22, Hartnett, as modified, teaches the pump (see Hartnett), further comprising a drive system (see fig. 6: hydraulic circuit 500) for cyclically providing the intermediate fluid to the intermediate fluid chamber (chamber on left side of the piston, see fig. 2) so that the elongated piston (310) is actuated to pump the cryogenic liquid from the fluid pumping chamber (see ¶29 and ¶37).
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over Hartnett in view of Durand and Noble and further in view of Pierce et al. (US 5,355,679 – herein after Pierce).
Hartnett teaches the pump of claim 17, wherein there exists a ratio of a diameter of the elongated cylinder to a longitudinal length of the elongated cylinder.
Hartnett remains silent on the pump wherein the ratio “is 8% or less”.
It is well-known in the art that sizing of a pump cylinder in a piston pump is dependent on various factors, such as but not limited to, a sizing of the piston (axial length of the piston and/or diameter of the piston). Pierce further teaches an expansion engine (10) submerged in a cryogenic environment (see fig. 1 and col. 3, lines 17-34). Pierce teaches: (see col. 10, lines 39-44) “As well the present invention is scaleable to achieve a wide range of different capacities for different gases. That is, without redesigning the essential structural features, the components may be sized as necessary to achieve desired capacities, or the piston stroke length or piston diameter may be changed”. Thus, Pierce discloses that sizing of a piston (a component in the engine) can be changed to achieve desired pumping capacities.
As demonstrated above, that the ratio is a result effective variable, wherein the ratio directly affects the “pumping capacity” and/or “sizing of the piston” in the reciprocating pump/engine. Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to have the ratio in the modified Hartnett’s pump “8% or less” since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Further, applicant places no criticality on the claimed range, indicating simply (see ¶61-¶62 of the pg. pub of the instant application) “Non-limiting examples of assembly and dimensions of the components of pump 310 of FIGS. 4A and 4B are presented in FIGS. 5-9. With reference to FIG. 5, piston 322 may be cylindrical with elliptical end caps 362 on each end and have a longitudinal length or height 364 of 30 inches. Pump housing 320 may be tube-shaped with a pump housing cylinder (323) longitudinal length or height 366 of approximately 49 inches. The diameter 368 of cylinder 323 may be approximately 4 inches. As a result, the ratio of the pump housing cylinder diameter to the length of the pump housing cylinder is approximately 8%.”.
Claims 24 and 25 are rejected under 35 U.S.C. 103 as being unpatentable over Hartnett in view of Durand and Noble and further in view of Drouvot Philippe (CH703376 – herein after Drouvot).
Hartnett, as modified, teaches the pump with the elongated piston.
Hartnett, as modified, does not teach the pump, wherein the elongated piston includes a polytetrafluoroethylene coating that is molded to provide circumferential seals, as in claim 24; and wherein the elongated piston includes a core upon which the polytetrafluoroethylene coating is placed, and wherein the core includes a cavity, as in claim 25.
However, Drouvot teaches a piston pump in cryogenic environment, wherein the elongated piston (4) includes a polytetrafluoroethylene coating (coating in the form of PTFE/bronze rings 43,44,45; see ¶18 of translation) that is molded to provide circumferential seals (rings provide sealing in circumferential direction) {with respect to feature “a polytetrafluoroethylene coating that is molded”: In accordance to MPEP 2113, the method of forming the device (in this PTFE coating “that is molded”) is not germane to the issue of patentability of the device itself. Therefore, this limitation has not been given patentable weight}, as in claim 24; and wherein the elongated piston (4) includes a core (body) upon which the polytetrafluoroethylene coating (coating in the form of PTFE/bronze rings 43,44,45) is placed, and wherein the core includes a cavity (groove 42), as in claim 25.
Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the piston head in the pumping chamber of modified Hartnett’s pump for providing sealing features as taught by Drouvot for the purpose of creating an effective seal, as recognized by Drouvot (see ¶18, lines 193-194 of translation).
Claim 26 is rejected under 35 U.S.C. 103 as being unpatentable over Hartnett in view of Durand and Noble and further in view of Rafalski, Jr (US 2009/0064672 – herein after Rafalski).
Hartnett teaches the pump, wherein (as discussed above in claim 1) the intermediate fluid (hydraulic fluid) is used.
Hartnett remains silent on the pump, wherein the intermediate fluid is “propane or 1-butene”.
However, Rafalksi teaches (see ¶14) a use of “propane” as a compressed fluid for driving a fluid motor.
It would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to substitute the hydraulic fluid in the modified Hartnett’s pump for “propane” as taught by Rafalksi in order to obtain the predictable result of pressurized fluid being applied to the hydraulic motor for reciprocating the pump piston in order to pump the desired fluid. KSR Int’l v. Teleflex Inc., 127 S. Ct. 1727, 1740-41, 82 USPQ2d 1385, 1396 (2007).
Response to Arguments
Applicant’s arguments, dated 11/14/2025, with respect to rejection of claims under 35 USC 112 have been considered but are persuasive. The rejections have been withdrawn.
Applicant’s arguments, dated 11/14/2025, with respect to prior art rejection of claims under 35 USC 103 have been considered.
With respect to independent claim 17: The amendment to this claim changed the scope of the claim. As a result, the prior arts have been re-evaluated and re-applied to this claim, in view of newly found and relied upon references of Hartnett and Durand.
With respect to independent claim 1: The amendment to this claim changed the scope of the claim. As a result, the previously applied prior arts have been re-evaluated and re-applied to this claim. Specifically, for claim 1, Noble has been re-evaluated and re-applied in view of newly found reference of Gustafson. Thus, the arguments with respect to Noble are moot.
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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/CHIRAG JARIWALA/Examiner, Art Unit 3746
/ESSAMA OMGBA/Supervisory Patent Examiner, Art Unit 3746