DETAILED ACTION
In Reply filed on 03/17/2026, claims 18-35 are pending. Claims 33-34 are withdrawn based on the restriction requirement. Claim 23 is currently amended. Claim 35 is newly added. Claims 18-32 and 35 are considered in the current Office 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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Status of Previous Objections/Rejections
Previous 35 USC 112(b) rejection is withdrawn based on the Applicant’s amendment.
35 USC 102 and 103 rejections are maintained in view of the Applicant’s argument. See response to argument below.
Claim Interpretation
Claim 29 recites the limitation “at least one means for controlling the heating” is a known terms of art and thus are interpreted broadly as any structure that is capable of controlling heating.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 18-22, 24-27, 29, and 32 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by KR101955923B1 (Kim), machine translation provided.
Regarding Claim 18, Kim teaches a liquefier assembly (Figure 2) for use in an extrusion-based additive manufacturing apparatus (abstract), comprising:
a liquefier tube extending between an inlet opening and an outlet opening (see annotated Figure 2),
wherein the inlet opening is configured to receive a consumable material (see annotated Figure 2, the inlet opening receives filament 190 and [0034]), and
wherein the liquefier tube is configured to facilitate the transport of the consumable material through the liquefier assembly between the inlet opening and the outlet opening (see annotated Figure 2, [0034]-[0035]),
a nozzle assembly (Figure 2, nozzle 250) coupled to the outlet opening of the liquefier tube (see annotated Figure 2) and configured to extrude the consumable material in a first direction ([0012]); and
a heater block assembly (Figure 5, heater block 230) disposed around at least a portion of the liquefier tube (Figure 5) and configured to heat the consumable material in the liquefier tube ([0012], a heater block for heating the filament in the nozzle), comprising a first major outer surface facing said first direction and a first recess in the first major outer surface (see annotated Figure 5),
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wherein the first recess exhibits, in section, at least one boundary edge configured to converge thermal radiation in substantially the first direction or a direction having an angle to said first direction (see annotated Figure 5 and [0052]).
Regarding Claim 19, Kim teaches the liquefier assembly according to claim 18, wherein the nozzle assembly is at least partly disposed in a portion of the first recess (Figure 5).
Regarding Claim 20, Kim teaches the liquefier assembly according to claim 18, wherein said first recess creates a cavity with respect to said nozzle assembly (Figure 5).
Regarding Claim 21, Kim teaches the liquefier assembly according to claim 18, wherein the first recess is a first cylindrical shaped recess extending in a working direction ([0051]), wherein the working direction corresponds to, when the liquefier assembly is in use, a direction in which it is moveable (Figure 5 is cross sectional view of the nozzle assembly which implied that the protrusions are displaced in a circumferential direction with at least one protrusion extended in a working direction and [0051]).
Regarding Claim 22, Kim teaches the liquefier assembly according to claim 21, wherein the major outer surface further comprises a second cylindrical shaped recess extending in the working direction (Figure 5 and [0051], a plurality of protrusions are present).
Regarding Claim 24, Kim teaches the liquefier assembly according to claim 18, wherein the at least one boundary edge of the recess, in section, defines a circular ([0051]), elliptical, parabolic, sinusoidal, rectangular, triangular, polygonal, or a smooth or piece-wise smooth shape.
Regarding Claim 25, Kim teaches the liquefier assembly according to claim 18, said at least one boundary edge of the recess is concave (Figure 5).
Regarding Claim 26, Kim teaches the liquefier assembly according to claim 18, wherein the major outer surface comprises a plurality of second recesses (Figure 5), wherein each second recess exhibiting, in section, at least one boundary edge configured to converge thermal radiation in substantially the first direction (Figure 5 and [0052]).
Regarding Claim 27, Kim teaches the liquefier assembly according to claim 26, wherein the first recess and the plurality of second recesses are disposed in a one- or two-dimensional pattern over at least a portion of the major outer surface (Figure 5).
Regarding Claim 29, Kim teaches the liquefier assembly according to claim 18, wherein the heater block assembly further comprises at least one cavity adapted to receive at least one means for controlling the heating of the consumable material (Figure 5, heater 235 is inserted into the heater block and applies heat to the entire heater block to heat and melt the filament [0038]).
Regarding Claim 32, Kim teaches the liquefier assembly according to claim 18, wherein the recess is multifaceted (Figure 5).
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 23 and 35 are rejected under 35 U.S.C. 103 as being unpatentable over KR101955923B1 (Kim), machine translation provided.
Regarding Claim 23, Kim teaches the liquefier assembly according to claim 22, but fails to explicitly teach wherein the first and the second cylindrical shaped recess are separated from each other over a core-to-core distance w, wherein w is between 0.8 and 20 times a diameter opening of the nozzle ϕ.
However, Kim discloses protrusions that surround the nozzle in the lower part of the heater block have an insulating effect by forming an air layer between the protrusions and the nozzle in order to maintain a uniform nozzle temperature. While Kim does not explicitly disclose changing spacing between the first and the second cylindrical shaped recess, the change in the spacing between the first and the second cylindrical shaped recess is not considered to confer patentability to the claims. As the nozzle temperature is a variable that can be modified, among others, by adjusting said spacing between the first and the second cylindrical shaped recess, with said nozzle temperature increases as the spacing between the first and the second cylindrical shaped recess decreases, the precise spacing between the first and the second cylindrical shaped recess would have been considered a result effective variable by one having ordinary skill in the art at the time the invention was made. As such, without showing unexpected results, the claimed spacing between the first and the second cylindrical shaped recess cannot be considered critical. Accordingly, one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the spacing between the first and the second cylindrical shaped recess in the apparatus of Kim to obtain the desired nozzle temperature (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223).
Regarding Claim 35, Kim teaches the liquefier assembly according to claim 23, but fails to explicitly teach wherein the core-to-core distance w is 1.2 times the diameter opening of the nozzle ϕ.
However, Kim discloses protrusions that surround the nozzle in the lower part of the heater block have an insulating effect by forming an air layer between the protrusions and the nozzle in order to maintain a uniform nozzle temperature. While Kim does not explicitly disclose changing spacing between the first and the second cylindrical shaped recess, the change in the spacing between the first and the second cylindrical shaped recess is not considered to confer patentability to the claims. As the nozzle temperature is a variable that can be modified, among others, by adjusting said spacing between the first and the second cylindrical shaped recess, with said nozzle temperature increases as the spacing between the first and the second cylindrical shaped recess decreases, the precise spacing between the first and the second cylindrical shaped recess would have been considered a result effective variable by one having ordinary skill in the art at the time the invention was made. As such, without showing unexpected results, the claimed spacing between the first and the second cylindrical shaped recess cannot be considered critical. Accordingly, one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the spacing between the first and the second cylindrical shaped recess in the apparatus of Kim to obtain the desired nozzle temperature (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223).
Claim 28 is rejected under 35 U.S.C. 103 as being unpatentable over KR101955923B1 (Kim), machine translation provided as applied to claim 18 above, and further in view of US2022/0227045 (Zhou).
Regarding Claim 28, Kim teaches the liquefier assembly according to claim 18, but fails to teach wherein at least the first recess and/or the plurality of second recesses have an emissivity of at least 0.03.
However, in the same field of endeavor of printhead for 3D printing comprises of a heating block, Zhou teaches the heating block may be made of a metallic material with the high thermal conduction efficiency, such as a stainless steel material ([0084]) which is known in the art to have an emissivity of 0.07 to 0.9. The first recess and/or the plurality of second recesses are a part of the heating block and thus are formed of the same material as the heating block.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modified the apparatus as taught by Kim such that it teaches all of the above discussed limitations as taught by Zhou with high thermal conduction to increase heat transfer ([0084]). Since the claimed range overlaps or lies inside ranges disclosed by the prior art, a prima facie case of obviousness exists. Please see MPEP 2144.05(I) and In re Wertheim, 541 F.2d 257, 191USPQ 90 (CCPA 1976) for further details.
Claim(s) 30-31 are rejected under 35 U.S.C. 103 as being unpatentable over KR101955923B1 (Kim), machine translation provided as applied to claim 18 above, and further in view of US2023/0150196 (“Mortimer et al” hereinafter Mortimer).
Regarding Claim 30, Kim teaches the liquefier assembly according to claim 18, but fails to explicitly teach wherein the heater block assembly further comprises at least a first part and a second part, wherein the first part is in direct contact with the nozzle assembly and the second part is removable attachable to the first part.
However, in the same field of endeavor of printhead for 3D printing comprises of a heating block, Mortimer discloses wherein the heater block assembly (Figure 10, split heater block 7) further comprises at least a first part (Figure 10, halves 7a) and a second part (Figure 10, halves 7b), wherein the first part is in direct contact with the nozzle assembly (Figure 10) and the second part is removable attachable to the first part ([0178], the halves 7 a , 7 b are configured to be secured together using screws; thus they are removable attached from one another through screws).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modified the apparatus as taught by Kim such that it discloses all of the above limitations as taught by Mortimer to allow for a closed-loop feedback control of temperature ([0182]). Furthermore, the combination of the known elements provides a predictable result, namely, another known heating block design. See MPEP 2143.
Regarding Claim 31, the modified Kim teaches the liquefier assembly according to claim 30, wherein the first recess is only disposed in the major outer surface of the second part (Mortimer, Figures 10 and 11).
Response to Arguments
Applicant's arguments filed 03/17/2026 have been fully considered but they are not persuasive.
The Applicant argues Kim fails to disclose “a heater block assembly disposed around at least a portion of the liquefier tube…wherein the first recess exhibits, in section, at least one boundary edge configured to converge thermal radiation in substantially the first direction or a direction having an angle to said first direction”. In particular, the protrusion structure in Kim is not configured to "converge" thermal radiation, nor is it capable of doing so. As explicitly defined in the present application, converging refers to the ability to increase the intensity of thermal radiation at a focal point or a line of focal points or a surface of focal points. (Specification para. [81]). In contrast, the objective in Kim is to prevent heat loss from the nozzle during active cooling of the filament, not to shape, focus, or direct radiant energy toward a printed layer. (Kim para. [17], [40]-[42]). The thermal environment created by Kim is inconsistent with a recess designed to converge thermal radiation, as recited in claim 18. Furthermore, the protrusions (237) is Kim may be formed in a circular, elliptical, or polygonal shapes, Kim is entirely silent regarding any design, dimensioning, or configuration of boundary edges for the purpose of converging or focusing thermal radiation. Kim provides no teaching or suggestion that the protrusions (237) actively direct radiant energy in any direction, let alone toward a printed layer as claimed.
The Examiner respectfully disagreed. Firstly, the Examiner is referring to the combination of heater block 230 and the protrusion 237 of Kim as a whole as equivalent to the heater block assembly of the claimed claim 18, see annotated Figure 2 of Kim. The heater block 230 surrounds the liquefier tube (see annotated Figure 2) and heats and melt the filament within the liquefier tube ([0038]). Secondly, under the broadest reasonable interpretation (BRI), the words of a claim must be given their plain meaning unless such meaning is inconsistent with the specification, and it is improper to import claim limitations from the specification into the claim. No where in claim 18 does it recites “shape, focus, or direct radiant energy toward a printed layer”. Kim discloses “protrusions that surround the nozzle 250 in the lower part of the heater block 230 have an insulating effect by forming an air layer between the protrusions and the nozzle or the blocking cap, It is possible to maintain a uniform nozzle temperature [0052]”. In other words, the protrusion of Kim functions to minimize heat lost, which increase intensity of thermal radiation, to maintain a constant nozzle temperature. Kim discloses a first recess and corresponding boundary edge to the first recess (see annotated Figure 2) to maintain a uniform nozzle temperature ([0052]). Furthermore, the Examiner wishes to point out the application claims are directed towards an apparatus and as such will be examined under such conditions. The material worked upon or the process of using the apparatus is viewed as recitation of intended use and is given patentable weight only to the extent that structure is added to the claimed apparatus (Please see MPEP 2112.01 and 2114-2115 for further details). Lastly, the reason or motivation to modify the reference may often suggest what the inventor has done, but for a different purpose or to solve a different problem. It is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by applicant. See, e.g., In re Kahn, 441 F.3d 977, 987, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006) (MPEP 2144. IV).
The Applicant argues no general conditions of first and the second cylindrical shaped recesses being separated from each other over a core-to-core distance are disclosed as directed to claim 23. Claim 23 requires, in part, “wherein the first and the second cylindrical shaped recess are separated from each other over a core-to-core distance w, and wherein w is between 0.8 and 20 times a diameter opening of the nozzle”. When starting from the teachings of Kim, one skilled in the art would not have been motivated to modify the protrusions (237) in order to arrive at the claimed configuration of the cylindrical-shaped recesses.
The Examiner respectfully disagreed. Kim discloses protrusions that surround the nozzle in the lower part of the heater block have an insulating effect by forming an air layer between the protrusions and the nozzle in order to maintain a uniform nozzle temperature ([0051]). Thus, the change in the spacing between the first and the second cylindrical shaped recess is not considered to confer patentability to the claims and one of ordinary skill in the art at the time the invention was made would have optimized, by routine experimentation, the spacing between the first and the second cylindrical shaped recess in the apparatus of Kim to obtain the desired nozzle temperature (In re Boesch, 617 F.2d. 272, 205 USPQ 215 (CCPA 1980)), since it has been held that where the general conditions of the claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. (In re Aller, 105 USPQ 223). The reason or motivation to modify the reference may often suggest what the inventor has done, but for a different purpose or to solve a different problem. It is not necessary that the prior art suggest the combination to achieve the same advantage or result discovered by applicant. See, e.g., In re Kahn, 441 F.3d 977, 987, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006) (MPEP 2144. IV). [0025] of the instant application discloses “This second cylindrical shaped recess has the advantage of reheating neighbouring elements of deposited material or strands. The conductive heat transfer will be lower which impacts the overall local cooling rate which will be slower”. However, this does the second cylindrical shaped recess is critical to produce lower conductive heat transfer but does not disclose the claimed range of core-to-core distance as critical. Therefore, the rejection is maintained.
Conclusion
THIS ACTION IS MADE FINAL. 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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XINWEN (CINDY) YE
Examiner
Art Unit 1754
/SUSAN D LEONG/ Supervisory Patent Examiner, Art Unit 1754
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