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 .
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1, 3-4, 10-12, 16-19, and 21-30 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 1, the limitation of “applying a layer of ceramic coating over an entire exterior surface of the 3D printed hollow shell forming a hardened ceramic mold, wherein the hardened ceramic mold being fully enclosed and having an opening at a lower end” in lines 6-8 is unclear and renders the claim indefinite. How is the mold “fully enclosed” if there is an opening?
Regarding claim 1, the limitation of “burying completely the pre-cast assembly under compared sand or ceramic beads wherein the inlet of the conduit is kept free and open at an upright position to receive a selected cast material in a molten state” in lines 12-14 is unclear and renders the claim indefinite. How is the pre-cast assembly buried “completely” if the conduit is “kept free and open”?
Regarding claim 1, the limitation of “molten state” and “a molten state” in lines 15, 16, and 18 should be changed to --the molten state—to refer to the molten state already recited in line 14.
Regarding claim 21, the limitation of “applying a layer of ceramic coating over an entire exterior surface of the 3D printed hollow shell forming a hardened ceramic mold, wherein the hardened ceramic mold being fully enclosed and having an opening at a lower end” in lines 5-7 is unclear and renders the claim indefinite. How is the mold “fully enclosed” if there is an opening?
Regarding claim 21, the limitation of “burying completely the pre-cast assembly under compared sand or ceramic beads wherein the inlet of the conduit is kept free and open at an upright position to receive a selected cast material in a molten state” in lines 11-13 is unclear and renders the claim indefinite. How is the pre-cast assembly buried “completely” if the conduit is “kept free and open”?
Regarding claim 21, the limitation of “molten state” and “a molten state” in lines 14, 15, and 17 should be changed to --the molten state—to refer to the molten state already recited in line 13.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1, 3-4, 10-12, and 16-19 is/are rejected under 35 U.S.C. 103 as being unpatentable over DeBruin (US 2017/0297086, cited in IDS filed 4/24/25) in view of Siak (US 2004/0069438) and Sokol et al (US 2018/0009128).
Regarding claim 1, DeBruin teaches a method for evaporative casting, comprising:
using three-dimensional printing to print only a hollow shell in 3D of at least one full-sized target part according to an algorithm (paragraph [0045], a model of the desired pattern form is developed using a computer aided design program, converted into a file, then 3-D printed, paragraph [0046], the pattern is at least partially hollow);
applying a layer of ceramic coating over an entire exterior surface of the 3D printed hollow shell forming a hardened ceramic mold (paragraph [0052], standard refractory coating is applied, paragraph [0053], refractory coating is dried thereby coating the entirety of the PLA form), wherein the hardened ceramic mold being fully enclosed (paragraph [0053], refractory coating the entirety of the PLA form);
forming a pre-cast assembly by connecting the hardened ceramic mold to an end of a conduit, while an opposite end of the conduit is configured as an inlet to the pre-cast assembly (paragraph [0053], PLA form is glued to a downsprue, funnel, or spout);
burying completely the pre-cast assembly under compacted sand or ceramic beads wherein the inlet of the conduit is kept free and open at an upright position to receive a selected cast material in a molten state (paragraph [0053-0054], the PLA form and downsprue, referred to as a cluster, are set on a bed of sand in a flask, additional sand is poured into the flask while vibrating to fill all spaces around the PLA form);
pouring the selected cast material in molten state into the inlet of the pre-cast assembly (paragraph [0056], molten iron or steel is poured into the downsprue which connects to the PLA form), wherein the selected cast material in a molten state travels down the conduit by gravity to entirely fill the pre-cast assembly by evaporating all of the 3D printed hollow shell, such that the selected cast material in a molten state completely fills up an entire volume enclosed by an inner surface of the hardened ceramic mold (paragraph [0056], poured into the downsprue, the PLA is vaporized and replaced by the molten metal); and
cooling to solidify the selected cast material inside the pre-cast assembly to yield a cast of the at least one full-sized target part (paragraph [0056], cooling of the casting).
DeBruin is quiet to the mold having an opening at a lower end, which is connected to the conduit.
Siak teaches a gravity-cast lost foam casting of metal castings, including a fugitive foam pattern forming a casting cavity and a hollow sprue for supplying melt to the casting cavity (abstract). The pattern 8 is coated with a thin gas-permeable ceramic layer (paragraph [0012]). In gravity cast lost foam processes, the gates are located either above the pattern for top filling or at the bottom of the mold cavity for bottom filling (paragraph [0003], fig 3). Siak teaches of the bottom fill arrangement (figs 1-5), where a solid foam runner (28) is shown connected to an opening at the lower end of the coated pattern (figs 1, 3-5, see ingate 32).
It would have been obvious to one of ordinary skill in the art to modify DeBruin so as to be a bottom fill arrangement, thus including an opening at a lower end of the mold connected to a conduit forming the runner, as Siak teaches that both top filling and bottom filling are known, and that it is known that a bottom fill provides a smoother non-turbulent flow. All the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395. MPEP 2143(I)(A).
The combination is quiet to wherein the 3D printed hollow shell is printed in an angled orientation, relative to a 3D printer printing the hollow shell, so that print layers are offset during 3D printing.
Sokol et al teaches an additive manufacturing printer that performs a layer-by-layer three-dimensional printing process generating a casting mold based on a three-dimensional numerical specification (abstract). Sokol et al teaches that a build orientation may range from perpendicular to the build platform or angled (figs 6-7, paragraph [0051]), and that part orientation may be based on various tradeoffs between build time, part resolution, surface finish, use of supports, platform size, vat depth, etc (paragraph [0051]).
It would have been obvious to one of ordinary skill in the art to modify the combination so as to include an angled orientation, as Sokol et al teaches that an angled orientation is known, and that the angle of the orientation can be optimized so as to take into account tradeoffs in build time, part resolution, surface finish, use of supports, platform size, vat depth, etc (paragraph [0051]).
Regarding claim 3, the combination teaches wherein the 3D printed hollow shell comprises polymer materials having a wall thickness between 0.15 mm and 1.00 mm (DeBruin, paragraph [0048], form 20 has an exterior up to 0.125 inches thick (3.175 mm), which overlaps the claimed range, where the thicknesses can be adjusted for different parts of the form).
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I).
Regarding claim 4, the combination teaches comprising attaching the 3D printed hollow shell of the at least one target part onto a separate gate frame, wherein the gate frame is either partly hollow or solid and is separately manufactured from a foam material (see combination, where Siak shows the coated pattern attached to solid foam 28 (paragraph [0013])).
Regarding claim 10, the combination is quiet to wherein the hardened ceramic mold has a wall thickness between 0.025 mm and 0.381 mm.
However, DeBruin teaches that the advantage of the invention in the use of the lost foam or evaporative casting process is to require only a single thin layer of refractory coating, rather than multiple thick coatings required by the lost wax method (paragraph [0041]). The thick refractory coating is costly and involves multiple coating steps, and removal requires far greater effort (paragraph [0041]). Furthermore, the refractory coating must be sufficiently strong to prevent the mold wall from collapsing during the vaporization process, while not so thick as to prevent the vaporized gas from escaping (paragraph [0060]).
It would have been obvious to one of ordinary skill in the art to optimize the wall thickness of the hardened ceramic mold, as DeBruin recognizes that thickness is a result effective variable, which must be sufficiently strong to prevent the mold wall from collapsing while not so thick as to prevent the vaporized gas from escaping (paragraph [0060]).
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). MPEP 2144.05(II).
Regarding claim 11, the combination teaches wherein the selected cast material comprises: aluminum alloys, brass alloys, copper alloys, bronze alloys, iron alloys, steel alloys, stainless steel, nickel, nickel alloys, or a combination thereof (DeBruin, paragraph [0056], iron or steel, paragraph [0061], alternatively, aluminum, brass, zinc).
Regarding claim 12, the combination teaches wherein the pre-cast assembly is buried in positions comprising one of: upright, inverted, and tilted at an angle (see combination, Siak, the pattern is buried upright).
Regarding claim 16, the combination teaches wherein the evaporated 3D printed hollow shell creates a gas within the hardened ceramic mold, the gas having a gas pressure, wherein the molten cast material includes a metal static pressure, and wherein the metal static pressure is greater than the gas pressure (DeBruin, paragraph [0057-0058], the molten metal kept at proper parameters so the gas pressure does not go back up the downsprue, but through the refractory coating and sand).
Regarding claim 17, the combination teaches wherein the gas within the hardened ceramic mold escapes from the hardened ceramic mold through a wall of the hardened ceramic mold (DeBruin, paragraph [0057-0058], matching the parameters so the gas does not go back up the downsprue and goes through the refractory coating).
Regarding claim 18, the combination teaches wherein the molten cast material evaporates the 3D printed hollow shell as the molten cast material comes close to the 3D printed hollow shell, creating a temporary shell-free area between the molten cast material and the 3D printed hollow shell (DeBruin, paragraph [0056], PLA is vaporized and replaced by molten metal, the temporary shell-free area is a result of the process using the same materials).
Regarding claim 19, the combination teaches wherein the gas within the hardened ceramic mold escapes from the hardened ceramic mold through a wall of the hardened ceramic mold in the shell-free area (DeBruin, paragraph [0056], PLA is vaporized and replaced by molten metal, paragraph [0057-0058], gas goes through the refractory coating, going through the shell-free area is a result of the process where the PLA is vaporized).
Claim(s) 21-30 is/are rejected under 35 U.S.C. 103 as being unpatentable over DeBruin (US 2017/0297086, cited in IDS filed 4/24/25) in view of Siak (US 2004/0069438) and Hondo (US 3,861,447).
Regarding claim 21, DeBruin teaches a method for evaporative casting, comprising:
using three-dimensional printing to print only a hollow shell in 3D of at least one full-sized target part according to an algorithm (paragraph [0045], a model of the desired pattern form is developed using a computer aided design program, converted into a file, then 3-D printed, paragraph [0046], the pattern is at least partially hollow);
applying a layer of ceramic coating over an entire exterior surface of the 3D printed hollow shell forming a hardened ceramic mold (paragraph [0052], standard refractory coating is applied, paragraph [0053], refractory coating is dried thereby coating the entirety of the PLA form), wherein the hardened ceramic mold being fully enclosed (paragraph [0053], refractory coating the entirety of the PLA form);
forming a pre-cast assembly by connecting the hardened ceramic mold to an end of a conduit, while an opposite end of the conduit is configured as an inlet to the pre-cast assembly (paragraph [0053], PLA form is glued to a downsprue, funnel, or spout);
burying completely the pre-cast assembly under compacted sand or ceramic beads wherein the inlet of the conduit is kept free and open at an upright position to receive a selected cast material in a molten state (paragraph [0053-0054], the PLA form and downsprue, referred to as a cluster, are set on a bed of sand in a flask, additional sand is poured into the flask while vibrating to fill all spaces around the PLA form);
pouring the selected cast material in molten state into the inlet of the pre-cast assembly (paragraph [0056], molten iron or steel is poured into the downsprue which connects to the PLA form), wherein the selected cast material in a molten state travels down the conduit by gravity to entirely fill the pre-cast assembly by evaporating all of the 3D printed hollow shell, such that the selected cast material in a molten state completely fills up an entire volume enclosed by an inner surface of the hardened ceramic mold (paragraph [0056], poured into the downsprue, the PLA is vaporized and replaced by the molten metal); and
cooling to solidify the selected cast material inside the pre-cast assembly to yield a cast of the at least one full-sized target part (paragraph [0056], cooling of the casting).
DeBruin is quiet to the mold having an opening at a lower end, which is connected to the conduit.
Siak teaches a gravity-cast lost foam casting of metal castings, including a fugitive foam pattern forming a casting cavity and a hollow sprue for supplying melt to the casting cavity (abstract). The pattern 8 is coated with a thin gas-permeable ceramic layer (paragraph [0012]). In gravity cast lost foam processes, the gates are located either above the pattern for top filling or at the bottom of the mold cavity for bottom filling (paragraph [0003], fig 3). Siak teaches of the bottom fill arrangement (figs 1-5), where a solid foam runner (28) is shown connected to an opening at the lower end of the coated pattern (figs 1, 3-5, see ingate 32).
It would have been obvious to one of ordinary skill in the art to modify DeBruin so as to be a bottom fill arrangement, thus including an opening at a lower end of the mold connected to a conduit forming the runner, as Siak teaches that both top filling and bottom filling are known, and that it is known that a bottom fill provides a smoother non-turbulent flow. All the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395. MPEP 2143(I)(A).
The combination of Debruin as modified by Siak is quiet to wherein perforations are formed through the 3D printed hollow shell.
Hondo teaches a casting method including embedding a form made of a combustible material in a flask, pouring a molten material into the form, whereupon the form is gassified and the resultant gases are positively removed from the mold system (abstract). Hondo teaches the form can include a gas vent 33 that can be formed integrally with the form 27, or can be formed independently of the form (col 4 lines 30-38). The gas vent enables the gases produced from the combustible form to be readily vented so that a casting of a predetermined shape and high quality can be produced (col 2 lines 1-10).
It would have been obvious to one of ordinary skill in the art to modify the combination so as to form a perforation, such as a gas vent, in the form as taught in Hondo, so as to readily vent gas produced during the vaporization of the pattern during casting. Furthermore, it would have been obvious to one of ordinary skill in the art to provide a plurality of the gas vents, so as to more readily vent the gases. Note that the courts have held that mere duplication of parts has no patentable significance unless a new and unexpected result is produced. see In re Harza, 274 F.2d 669, 124 USPQ 378 (CCPA 1960). MPEP 2144.04(VI)(B).
Regarding claim 22, the combination teaches wherein the 3D printed hollow shell comprises polymer materials having a wall thickness between 0.15 mm and 1.00 mm (DeBruin, paragraph [0048], form 20 has an exterior up to 0.125 inches thick (3.175 mm), which overlaps the claimed range, where the thicknesses can be adjusted for different parts of the form).
In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). MPEP 2144.05(I).
Regarding claim 23, the combination teaches comprising attaching the 3D printed hollow shell of the at least one target part onto a separate gate frame, wherein the gate frame is either partly hollow or solid and is separately manufactured from a foam material (see combination, where Siak shows the coated pattern attached to solid foam 28 (paragraph [0013])).
Regarding claim 24, the combination is quiet to wherein the hardened ceramic mold has a wall thickness between 0.025 mm and 0.381 mm.
However, DeBruin teaches that the advantage of the invention in the use of the lost foam or evaporative casting process is to require only a single thin layer of refractory coating, rather than multiple thick coatings required by the lost wax method (paragraph [0041]). The thick refractory coating is costly and involves multiple coating steps, and removal requires far greater effort (paragraph [0041]). Furthermore, the refractory coating must be sufficiently strong to prevent the mold wall from collapsing during the vaporization process, while not so thick as to prevent the vaporized gas from escaping (paragraph [0060]).
It would have been obvious to one of ordinary skill in the art to optimize the wall thickness of the hardened ceramic mold, as DeBruin recognizes that thickness is a result effective variable, which must be sufficiently strong to prevent the mold wall from collapsing while not so thick as to prevent the vaporized gas from escaping (paragraph [0060]).
"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). MPEP 2144.05(II).
Regarding claim 25, the combination teaches wherein the selected cast material comprises: aluminum alloys, brass alloys, copper alloys, bronze alloys, iron alloys, steel alloys, stainless steel, nickel, nickel alloys, or a combination thereof (DeBruin, paragraph [0056], iron or steel, paragraph [0061], alternatively, aluminum, brass, zinc).
Regarding claim 26, the combination teaches wherein the pre-cast assembly is buried in positions comprising one of: upright, inverted, and tilted at an angle (see combination, Siak, the pattern is buried upright).
Regarding claim 27, the combination teaches wherein the evaporated 3D printed hollow shell creates a gas within the hardened ceramic mold, the gas having a gas pressure, wherein the molten cast material includes a metal static pressure, and wherein the metal static pressure is greater than the gas pressure (DeBruin, paragraph [0057-0058], the molten metal kept at proper parameters so the gas pressure does not go back up the downsprue, but through the refractory coating and sand).
Regarding claim 28, the combination teaches wherein the gas within the hardened ceramic mold escapes from the hardened ceramic mold through a wall of the hardened ceramic mold (DeBruin, paragraph [0057-0058], matching the parameters so the gas does not go back up the downsprue and goes through the refractory coating).
Regarding claim 29, the combination teaches wherein the molten cast material evaporates the 3D printed hollow shell as the molten cast material comes close to the 3D printed hollow shell, creating a temporary shell-free area between the molten cast material and the 3D printed hollow shell (DeBruin, paragraph [0056], PLA is vaporized and replaced by molten metal, the temporary shell-free area is a result of the process using the same materials).
Regarding claim 30, the combination teaches wherein the gas within the hardened ceramic mold escapes from the hardened ceramic mold through a wall of the hardened ceramic mold in the shell-free area (DeBruin, paragraph [0056], PLA is vaporized and replaced by molten metal, paragraph [0057-0058], gas goes through the refractory coating, going through the shell-free area is a result of the process where the PLA is vaporized).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JACKY YUEN whose telephone number is (571)270-5749. The examiner can normally be reached 9:30 - 6:00.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Walker can be reached at 571-272-3458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/JACKY YUEN/
Examiner
Art Unit 1735
/KEITH WALKER/Supervisory Patent Examiner, Art Unit 1735