DETAILED ACTION
Response to Amendment
The Amendment filed 12 May 2026 has been entered. Claims 1, 3, 4, 6-8, 10-12, and 21-23 remain pending in the application. Claims 2, 5, 9, 13-20 have been canceled. New claims 24 and 25 have been added. Applicant's amendments to the claims have overcome the 112(b) rejections previously set forth in the Non-Final Rejection mailed 02 February 2026.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 26 October 2023 and 03 March 2025 were considered by the examiner. The submission is in compliance with the provisions of 37 CFR 1.97.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
Claim 24 is rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 24 claims that the rod is solid throughout a length, however, applicant does not disclose the rod being solid in the instant specification. Applicant also does not mention the rod being solid specifically throughout any certain length.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 3, 4, 8, 11, 12, 21, 24, and 25 are rejected under 35 U.S.C. 103 as being unpatentable over US6106226 of Morando in view of US20150040376 of Muller further in view of WO2016025676 of Henderson and US3880055 of Nakamura.
Claim 1 claims a molten metal pump post comprising: a rod of a first material; an inner member at least partially surrounding the rod wherein the inner member is of a second material; and wherein a difference in a coefficient of thermal expansion between the rod and the inner member creates a compressive force and wherein the first material of the rod provides no compressive force at room temperature and provides compressive force at a temperature above 500°C.
Morando discloses a high velocity prestressed shaft for degasser or pumping application in molten metal in the same field of endeavor as the claimed invention. Morando teaches a shaft which includes a prestressed, tubular shield that is in a state of longitudinal compression as it is being rotated, Para[0001]. Morando also teaches that the shield (equivalent to the claimed inner member), is of a material that has a different coefficient of thermal expansion than the shaft (equivalent to the claimed elongated rod), Para[0035]. Morando does not specifically teach a compressive force provided by the first material at a temperature above 500°C. The instant specification discloses that the rod is carbon-carbon and the inner member is silicon carbide, Para[0051]. Applicant also discloses that the inner member can comprise Tungsten, Titanium or other similar material.
Muller teaches methods for manufacturing thin-walled enclosures and related system and apparatus in a similar field of endeavor as the claimed invention. Muller discloses that in other embodiments the coefficient of thermal expansion of the support material can differ from that of the material defining the component. For example, in some embodiments the coefficient of thermal expansion of the support material can be higher than the coefficient of thermal expansion of the material defining the component. In this regard, when the support material is employed to at least partially surround the component, the support material can apply a preload to the component in the form of compressive forces, which can be useful in counteracting forces applied to the component during manufacturing operations, Para[0031]. Therefore, it would be obvious to one of ordinary skill in the art to use the compressive forces induced by the difference in coefficient of thermal expansion as taught by Muller in the shaft and shield disclosed by Morando in order to counteract the forces acting on it during operation.
Henderson discloses advanced material for molten metal processing equipment in the same field of endeavor as the claimed invention. Henderson teaches C/C composites as molten pump components having thermal stability, high resistance to thermal shock due to high thermal conductivity, and low thermal expansion behavior, i.e., low thermal expansion coefficient. These materials are also characterized as having high toughness, strength and stiffness in high temperature applications, Para[0032]. Henderson discloses that the bearing rings are made of a material, such as silicon carbide, having frictional bearing properties at high temperatures to prevent cyclic failure due to high frictional forces, Para[0054]. Therefore, it would be obvious to one of ordinary skill in the art to produce the components disclosed in Morando using the carbon-carbon material and silicon carbide disclosed in Henderson to achieve good high temperature properties.
Nakamura teaches an injection pump for use in hot chamber type die cast machines in a similar field of endeavor as the claimed invention. Nakamura teaches a cylinder with guide rings (equivalent to the claimed inner member), of tungsten, Para[0026]. Nakamura teaches that as a result of using tungsten, it is possible to use simple machine tools and cheap materials, thus decreasing the cost of manufacturing of the injection pump, Para[0039]. Therefore, it would be obvious to one of ordinary skill in the art to produce the inner member disclosed in Morando using tungsten to achieve a decreased cost of manufacturing.
Thus, Morando in view of Muller further in view of Henderson and Nakamura teaches a product that is substantially identical in structure and composition to that of the claimed invention. Therefore, a prima facie case of obviousness has been established, see MPEP 2112.01. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 1.
Claim 3 further limits claim1 by claiming that the first material of the rod comprises steel or a steel alloy.
Morando discloses a shaft, equivalent to elongated rod, of steel or a steel alloy, Para[0035]. Thus, Morando covers the additional limitation of claim 3. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 3.
Claim 4 further limits claim 1 by claiming that the second material of the inner member comprises tungsten and/or titanium.
Morando does not disclose tungsten and/or titanium.
Nakamura teaches a cylinder with guide rings (equivalent to the claimed inner member), of tungsten, Para[0026]. Nakamura teaches that as a result of using tungsten, it is possible to use simple machine tools and cheap materials, thus decreasing the cost of manufacturing of the injection pump, Para[0039]. Therefore, it would be obvious to one of ordinary skill in the art to produce the inner member disclosed in Morando using tungsten to achieve a decreased cost of manufacturing. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 4.
Claim 8 further limits claim 1 by claiming that the rod comprises carbon carbon.
Morando does not teach carbon-carbon.
Henderson discloses advanced material for molten metal processing equipment in the same field of endeavor as the claimed invention. Henderson teaches C/C composites as molten pump components having thermal stability, high resistance to thermal shock due to high thermal conductivity, and low thermal expansion behavior, i.e., low thermal expansion coefficient. These materials are also characterized as having high toughness, strength and stiffness in high temperature applications, Para[0032]. Therefore, it would be obvious to one of ordinary skill in the art to produce the components disclosed in Morando using the carbon-carbon material disclosed in Henderson to achieve good high temperature properties. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 8.
Claim 11 further limits claim 1 by claiming an outer sheath.
Morando discloses an outer shield (equivalent to an outer sheath), Para[0020]. Thus, Morando covers the additional limitation of claim 11. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 11.
Claim 12 further limits claim 11 by claiming that the inner member is disposed between the rod and the outer sheath.
Morando teaches a shaft which includes a multi-layer shield assembly including an outer tubular ceramic shield (equivalent to an outer sheath), and an inner tubular ceramic shield (equivalent to an inner member), Para[0017]. Thus, Morando covers the additional limitation of claim 12. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 12.
Claim 21 claims A molten metal pump including the molten metal pump post of claim 1.
Morando discloses a high velocity prestressed shaft for degasser or pumping application in molten metal in the same field of endeavor as the claimed invention. Morando teaches a shaft which includes a prestressed, tubular shield that is in a state of longitudinal compression as it is being rotated, Para[0001]. Morando also teaches that the shield (equivalent to the claimed inner member), is of a material that has a different coefficient of thermal expansion than the shaft (equivalent to the claimed elongated rod), Para[0035]. Morando also teaches that the shaft assembly can be used as a pump member, Para[0009]. Morando does not specifically teach a compressive force provided by the first material at a temperature above 500°C. The instant specification discloses that the rod is carbon-carbon and the inner member is silicon carbide, Para[0051]. Applicant also discloses that the inner member can comprise Tungsten, Titanium or other similar material.
Muller teaches methods for manufacturing thin-walled enclosures and related system and apparatus in a similar field of endeavor as the claimed invention. Muller discloses that in other embodiments the coefficient of thermal expansion of the support material can differ from that of the material defining the component. For example, in some embodiments the coefficient of thermal expansion of the support material can be higher than the coefficient of thermal expansion of the material defining the component. In this regard, when the support material is employed to at least partially surround the component, the support material can apply a preload to the component in the form of compressive forces, which can be useful in counteracting forces applied to the component during manufacturing operations, Para[0031]. Therefore, it would be obvious to one of ordinary skill in the art to use the compressive forces induced by the difference in coefficient of thermal expansion as taught by Muller in the shaft and shield disclosed by Morando in order to counteract the forces acting on in during operation.
Henderson discloses advanced material for molten metal processing equipment in the same field of endeavor as the claimed invention. Henderson teaches C/C composites as molten pump components having thermal stability, high resistance to thermal shock due to high thermal conductivity, and low thermal expansion behavior, i.e., low thermal expansion coefficient. These materials are also characterized as having high toughness, strength and stiffness in high temperature applications, Para[0032]. Henderson discloses that the bearing rings are made of a material, such as silicon carbide, having frictional bearing properties at high temperatures to prevent cyclic failure due to high frictional forces, Para[0054]. Therefore, it would be obvious to one of ordinary skill in the art to produce the components disclosed in Morando using the carbon-carbon material and silicon carbide disclosed in Henderson to achieve good high temperature properties.
Nakamura teaches an injection pump for use in hot chamber type die cast machines in a similar field of endeavor as the claimed invention. Nakamura teaches a cylinder with guide rings (equivalent to the claimed inner member), of tungsten, Para[0026]. Nakamura teaches that as a result of using tungsten, it is possible to use simple machine tools and cheap materials, thus decreasing the cost of manufacturing of the injection pump, Para[0039]. Therefore, it would be obvious to one of ordinary skill in the art to produce the inner member disclosed in Morando using tungsten to achieve a decreased cost of manufacturing.
Thus, Morando in view of Muller further in view of Henderson and Nakamura teach a product that is substantially identical in structure and composition to that of the claimed invention. Therefore, a prima facie case of obviousness has been established, see MPEP 2112.01. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 21.
Claim 24 further limits claim 1 by claiming that the rod is solid throughout a length. This limitation is not supported, see 112(a) rejection above.
Additionally, Morando’s steel rod is solid, Para[0035].
Claim 25 further limits claim 21 by claiming that the rod is held in compression above 500°C without reliance on a motor mount, a pump base or springs.
Morando does not specifically teach a compressive force provided by the first material at a temperature above 500°C. The instant specification discloses that the rod is carbon-carbon and the inner member is silicon carbide, Para[0051]. Applicant also discloses that the inner member can comprise Tungsten, Titanium or other similar material.
Muller teaches methods for manufacturing thin-walled enclosures and related system and apparatus in a similar field of endeavor as the claimed invention. Muller discloses that in other embodiments the coefficient of thermal expansion of the support material can differ from that of the material defining the component. For example, in some embodiments the coefficient of thermal expansion of the support material can be higher than the coefficient of thermal expansion of the material defining the component. In this regard, when the support material is employed to at least partially surround the component, the support material can apply a preload to the component in the form of compressive forces, which can be useful in counteracting forces applied to the component during manufacturing operations, Para[0031]. Therefore, it would be obvious to one of ordinary skill in the art to use the compressive forces induced by the difference in coefficient of thermal expansion as taught by Muller in the shaft and shield disclosed by Morando in order to counteract the forces acting on in during operation, resulting in no need for the springs taught by Morando.
Henderson discloses advanced material for molten metal processing equipment in the same field of endeavor as the claimed invention. Henderson teaches C/C composites as molten pump components having thermal stability, high resistance to thermal shock due to high thermal conductivity, and low thermal expansion behavior, i.e., low thermal expansion coefficient. These materials are also characterized as having high toughness, strength and stiffness in high temperature applications, Para[0032]. Henderson discloses that the bearing rings are made of a material, such as silicon carbide, having frictional bearing properties at high temperatures to prevent cyclic failure due to high frictional forces, Para[0054]. Therefore, it would be obvious to one of ordinary skill in the art to produce the components disclosed in Morando using the carbon-carbon material and silicon carbide disclosed in Henderson to achieve good high temperature properties.
Nakamura teaches an injection pump for use in hot chamber type die cast machines in a similar field of endeavor as the claimed invention. Nakamura teaches a cylinder with guide rings (equivalent to the claimed inner member), of tungsten, Para[0026]. Nakamura teaches that as a result of using tungsten, it is possible to use simple machine tools and cheap materials, thus decreasing the cost of manufacturing of the injection pump, Para[0039]. Therefore, it would be obvious to one of ordinary skill in the art to produce the inner member disclosed in Morando using tungsten to achieve a decreased cost of manufacturing.
Thus, Morando in view of Muller further in view of Henderson and Nakamura teach a product that is substantially identical in structure and composition to that of the claimed invention. Therefore, a prima facie case of obviousness has been established, see MPEP 2112.01. Thus, Morando, Muller, Henderson, and Nakamura cover all limitations of claim 25.
Claims 6 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over US6106226 of Morando in view of US20150040376 of Muller further in view of WO2016025676 of Henderson and US3880055 of Nakamura, as cited above, further in view of EP2518274 of McCaffrey.
Claim 6 further limits claim 1 by claiming that the difference in coefficient of thermal expansion is at least 0.001852 ppm/°C.
Morando does not specifically disclose the numerical limitation for difference in coefficient of thermal expansion. However, Morando discloses the shield (equivalent to the claimed inner member), made of graphite or ceramic, Para[0004], and the shaft (equivalent to the claimed elongated rod), of steel, Para[0035]. It is well known in the art that steel has a coefficient of thermal expansion in the range of 11 to 13 ppm/°C, and refractory graphite has a coefficient of thermal expansion in the range of 0.5-2 ppm/°C.
McCaffrey teaches blade clearance control using high-CTE and low-CTE ring members in a similar field of endeavor as the claimed invention. McCaffrey teaches ceramics and ceramic matrix composites (CMC) and have an exemplary CTE range of up to 2.5 ppm/C, Para[0015].
Therefore, based on the teachings of Morando and McCaffrey and well-known coefficient of thermal expansions, it would be obvious to one of ordinary skill in the art to use the materials disclosed in Morando, achieving a difference of coefficient of thermal expansion between the steel and the ceramic/graphite in the range of 8.5 - 13 ppm/°C. This exceeds the claimed minimum of 0.001852 ppm/°C. Thus, Morando, Muller, Henderson, Nakamura, and McCaffrey cover all limitations of claim 6.
Claim 7 further limits claim 1 by claiming that the difference in coefficient of thermal expansion is at least 0.011109 ppm/°C.
Morando does not specifically disclose the numerical limitation for difference in coefficient of thermal expansion. However, Morando discloses the shield (equivalent to the claimed inner member), made of graphite or ceramic, Para[0004], and the shaft (equivalent to the claimed elongated rod), of steel, Para[0035]. It is well known in the art that steel has a coefficient of thermal expansion in the range of 11 to 13 ppm/°C, and refractory graphite has a coefficient of thermal expansion in the range of 0.5-2 ppm/°C.
McCaffrey teaches blade clearance control using high-CTE and low-CTE ring members in a similar field of endeavor as the claimed invention. McCaffrey teaches ceramics and ceramic matrix composites (CMC) and have an exemplary CTE range of up to 2.5 ppm/C, Para[0015].
Therefore, based on the teachings of Morando and McCaffrey and well-known coefficient of thermal expansions, it would be obvious to one of ordinary skill in the art to use the materials disclosed in Morando, achieving a difference of coefficient of thermal expansion between the steel and the ceramic/graphite in the range of 8.5 - 13 ppm/°C. This exceeds the claimed minimum of 0.011109 ppm/°C. Thus, Morando, Muller, Henderson, Nakamura, and McCaffrey cover all limitations of claim 7.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over US6106226 of Morando in view of US20150040376 of Muller further in view of WO2016025676 of Henderson and US3880055 of Nakamura, as cited above, further in view of US3612715 of Yedidiah.
Claim 10 further limits claim 8 by claiming a stainless-steel flange coupled to the elongated rod.
Morando does not teach a stainless-steel flange.
Henderson discloses advanced material for molten metal processing equipment in the same field of endeavor as the claimed invention. While Henderson discloses a flange, Para[0046], stainless steel is not taught.
Yedidiah teaches a pump for molten metal and other high-temperature corrosive liquids in the same field of endeavor as the claimed invention. Yedidiah discloses that Accordingly, the drive shaft, which includes a flange portion, may, in accordance with the invention, be constructed of a metallic material like stainless steel much more able to withstand the shear stresses developed during the pumping operation than the refractory drive shafts prevalent in the prior art, Para[0006].
Therefore, based on the teachings of Morando, Henderson and Yedidiah it would be obvious to one of ordinary skill in the art to produce the rod with a stainless-steel flange so it would be more able to withstand shear stresses developed during pumping. Thus, Morando, Muller, Henderson, Nakamura, and Yedidiah cover all limitations of claim 10.
Claims 22 and 23 are rejected under 35 U.S.C. 103 as being unpatentable over US6106226 of Morando in view of US20150040376 of Muller further in view of WO2016025676 of Henderson and US3880055 of Nakamura, as cited above, further in view of US6887425 of Mordue.
Claim 22 further limits claim 21 by claiming a cap and a base.
Morando Morando does not teach a cap and base
Mordue teaches Shaft and post assemblies for molten metal apparatus in the same field of endeavor as the claimed invention. Mordue teaches a steel shaft surrounded by a ceramic post, Para[0001]. Mordue teaches that the rod is fastened to the base by maneuvering the rod placing the cap into the second cavity while the rod and the annular refractory member slide into the first channel, Para[0097]
Therefore, it would be obvious to one of ordinary skill in the art to produce the assembly disclosed in Mordue, including a cap and a base, using the materials with differing coefficient of thermal expansions disclosed in Morando in order for the rod to be slid into place. Thus, Morando, Muller, Henderson, Nakamura, and Mordue cover all limitations of claim 22.
Claim 23 further limits claim 22 by claiming the cap is removably coupled to the base.
Morando does not teach a cap and base.
Mordue teaches that the rod extends through the base and includes a threaded end on which graphite cap is secured, Para[0065]. Therefore, it would be obvious to one of ordinary skill in the art to produce the assembly disclosed in Mordue, including a removably coupled cap and a base, using the materials with differing coefficient of thermal expansions disclosed in Morando in order for the rod to be slid into place. Thus, Morando, Muller, Henderson, Nakamura, and Mordue cover all limitations of claim 23.
Response to Arguments
Applicant's arguments filed 12 May 2026 have been fully considered but they are not persuasive. Applicant argues that (remarks, page 1 of 4) that primary reference Morando cannot anticipate the presently claimed invention because Morando is directed to a shaft for a degassing device, not a post. This is not found persuasive because a reference need not be from the same field of endeavor as the claimed invention in order to be analogous art, see MPEP 2141.01. Additionally, this argument is moot as the new grounds of rejection necessitated by the amendment of claim 1 is not a 102-anticipation rejection but a 103-obviousness rejection with Morando in view of Muller, Henderson, and Nakamura.
Applicant argues that (remarks, page 2 of 4) Morando does not anticipate claim 1 because Morando only teaches compressive forces from springs and does not teach a compressive force caused by a difference in CTE of the materials. This argument is moot as the new grounds of rejection necessitated by amendment of claim 1 relies on Muller for teaching the compressive force related to CTE. One of ordinary skill in the art would be able to use the compressive forces taught by Muller with the shaft assembly taught by Morando to counteract the forces applied to the pump post during operation, which would stabilize the assembly making a spring unnecessary.
Examiner’s Note
Examiner has attached previously-cited foreign references that were inadvertently omitted in the non-final action. References Included: EP2518274 and WO2016025676
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 JACOB BENJAMIN STILES whose telephone number is (571)272-0598. The examiner can normally be reached Monday-Friday 7:30am - 5:00pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Hendricks can be reached at (571) 272-1401. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Keith D. Hendricks/Supervisory Patent Examiner, Art Unit 1733
/JACOB BENJAMIN STILES/Examiner, Art Unit 1733
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