Prosecution Insights
Last updated: April 19, 2026
Application No. 19/078,923

METHOD FOR MANUFACTURING HEAT EXCHANGER

Final Rejection §103
Filed
Mar 13, 2025
Examiner
AVERICK, LAWRENCE
Art Unit
3799
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Daikin Industries Ltd.
OA Round
2 (Final)
76%
Grant Probability
Favorable
3-4
OA Rounds
2y 10m
To Grant
99%
With Interview

Examiner Intelligence

Grants 76% — above average
76%
Career Allow Rate
498 granted / 658 resolved
+5.7% vs TC avg
Strong +24% interview lift
Without
With
+23.6%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
13 currently pending
Career history
671
Total Applications
across all art units

Statute-Specific Performance

§101
0.9%
-39.1% vs TC avg
§103
47.1%
+7.1% vs TC avg
§102
29.5%
-10.5% vs TC avg
§112
20.9%
-19.1% vs TC avg
Black line = Tech Center average estimate • Based on career data from 658 resolved cases

Office Action

§103
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 . Prior art of Record The prior art made of record in this office action shall be referred to as follows; U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), App 13/401130; Filed 02/21/2012 U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter), App 10689879; Filed 10/21/2003; U.S. 2022/0412669 Harata et al. (‘Harata hereafter), App 17/780924; Filed 11/27/2020; U.S. 2012/0055014 Branyon et al. (‘Branyon hereafter), App 13/297670; Filed 11/16/2011; U.S. 5,644,841 Stewart et al. (‘Stewart hereafter), Filed 06/05/1996; The above references will be referred to hereafter by the names or numbers indicated above. Claim status: Claims 1 – 10 & 11 - 16 are currently being examined. No Claims have been withdrawn. No Claims have been canceled. No Claims are allowed or objected to for allowable subject matter. Claim Rejections - 35 USC § 103 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 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. 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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action. 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. 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 1, 3 – 7 & 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), and in view of U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter). Regarding Claim[s] 1, ‘Milliman discloses all the claim limitations including: A method for manufacturing a heat exchanger (‘Milliman, Para 0001, “This invention relates to a tube pressure expansion device and, more particularly, a device that is adapted to pressure-expand plural tubes embodied in a workpiece coil at the same time.” Para 0004, “The objects and purposes of the invention are met by providing a tube pressure expansion device for expanding plural hollow tubes on a workpiece coil having plural fins. Each hollow tube has an open free end to an interior thereof. A pressure expansion manifold has plural cavities each configured to receive a free end of a respective tube on the workpiece coil. An interior wall surface in each cavity includes a tube seating wall surface. A hollow bullet is provided in each cavity and is configured for entering the tube opening at each free end for effecting an expansion of each free end to urge the material of each free end into a clamped and sealed relation with the tube seating wall surface in each said cavity. Plural passageways are provided in the pressure expansion manifold and each are configured to supply a pressurized fluid to an interior of each of the hollow bullets to effect a pressurization of the interior of each of the tubes to effect an expansion of the tubes into an interference fit with the fins on the workpiece coil.” Discusses applicant’s advantages of their invention for the manufacturing of a heat exchanger), the heat exchanger (‘Milliman, #WC (workpiece coil/ heat exchanger)) comprising a plate-shaped fin (‘Milliman, #F (sheet metal fins/ plate-shaped fins)) and a circular heat transfer tube (‘Milliman, Fig 4A2, shows #T (U-Shaped tubes) that are straight tube bent into a “U” shape, and #CE (cylindrical end)), the method comprising: inserting the circular heat transfer tube through a through hole in the plate-shaped fin (‘Milliman, Fig 4A2, shows tube through #F (sheet metal plate); and expanding an outside diameter of the inserted circular heat transfer tube (‘Milliman, Fig 6A1, shows #10 (tube pressure expander device), #36 (piston), #T (U-shaped tube), #39 (tapered bullet), #37 (piston rod), Para 0044, teaches the expansion of the outside diameter of the heat transfer tube #T) and fixing the plate-shaped fin to the circular heat transfer tube (‘Milliman, Fig 8), wherein the expanding of the outside diameter comprises pushing a tube expansion plug into the circular heat transfer tube and increasing the outside diameter of the circular heat transfer tube (‘Milliman, Fig 6A1, #39 (tapered bullet) is an expansion plug pushed into the tube #T, and thereby increasing the outside diameter of the tube), Except ‘Milliman is silent regarding: wherein the tube expansion plug comprises a plug body made of a cemented carbide and a diamond film configured to cover a surface of the plug body. However, ‘Kelly teaches: wherein the tube expansion plug comprises a plug body made of a cemented carbide and a diamond film configured to cover a surface of the plug body (‘Kelly, Para 0040, “[0040] In a subsequent rotary forging process, the barrel blanks may essentially be extruded from a diameter of 7.87 mm down to a final 5.56 mm diameter. In this process, a solid carbide die is placed inside the barrel. This die has the rifling machined into it, and the rifling is then transferred to the barrel as the extrusion takes place. The forging mandrel is sized to produce a final rifled dimension on the coated blanks after forging. Tungsten carbide mandrels may be treated with a diamond coating to provide wear resistance during the rotary forging operation. The coated barrels may be subjected to destructive evaluation in order to verify the metallurgical bond, as well as other properties of the coatings. FIG. 5 is a micrograph of a gun barrel cross section after rotary forging and extrude-honing.”). Hence, it would have been obvious to one of ordinary skill in the art at the effective filing date of the claimed invention to provide ‘Milliman with a Tungsten Carbide mandrel expansion tool with a diamond coating as taught by ‘Kelley in order to provide wear resistance during the operation of the expansion (‘Kelly, Para 0040). ; and bringing an outer surface of a portion of the circular heat transfer tube (30) into tight contact with the plate-shaped fin (20) (‘Milliman, Figs 4A2, 5A1, 5B1, 5B2, 5C1, 5C2, 6A1, 6A2, 7A1, 7A2, 8, 8A, Show #F (sheet metal fins/ fins) and #T (U-shaped tubes/ heat transfer tube) in an assembled system, Abst teaches: “A pressurized fluid is supplied to an interior of the hollow tapered bullet to effect a pressurization of the interior of the tubes to effect an expansion of the tubes into an interference fit with the fins on the workpiece coil.” Interference Fit is a tight contact) ,, wherein the portion is plastically deformed and expanded by the tube expansion plug (60) (‘Milliman, Para 0002, “It is known to expand the diameter of tubes by applying a pressurized fluid to the interior thereof so that the exterior surface thereof expands into contact with the fins of a heat exchanger coil for use in the heating, ventilating and air conditioning (HVAC) industry and U.S. Pat. No. 5,765,284 is a representative example. One of the problems faced by the manufacturers of the HVAC coils is to inexpensively pressure-expand a plurality of U-shaped tubes, known in the field as hairpin tubes, wherein the legs of the U-shaped tubes are each loosely laced through openings in the fins of the coil at the same time.”). Regarding Claim[s] 3 & 5 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: an arithmetic average roughness of a surface of the diamond film of the tube expansion plug is 0.023 μm or less. ‘Kelly does not teach a specific roughness. However, ‘Kelly does teach: Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish. It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish of the diamond coated mandrel to 0.023 μm 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 Bosch, 617 F, 2d 272, 205 USPQ 215 (CCPA 1980). Regarding Claim[s] 4, ‘Milliman, and ‘Kelly discloses all the claim limitations including: the tube expansion plug has a base end and a distal end (‘Milliman, Fig 6A1, #39 (tapered bullet/ expansion plug) shows a distal end, Fig 5C1 shows #39 with a base end), and the tube expansion plug comprises: a first portion disposed between the base end and the distal end and at which the tube expansion plug has a largest outside diameter (‘Milliman, Fig 5C1); an enlarged diameter portion disposed from the distal end to the first portion and that has an outside diameter that increases gradually from the distal end toward the first portion (‘Milliman, Fig 5C1); and a second portion disposed within the enlarged diameter portion and that has an outside diameter equal to an inside diameter of the circular heat transfer tube (30) before the tube expansion step (‘Milliman, Fig 5C1, shows #39 (tapered bullet. Expansion plug) fits into the tube diameter partially before the pressure is applied to expand the end tube diameter), and an arithmetic average roughness of a surface of the diamond film at the second portion is lower than an arithmetic average roughness of a surface of the diamond film at the first portion (‘Kelly, Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish.) It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish after the expansion to have a second portion of a lower roughness that the surface of the diamond portion, 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). Regarding Claim[s] 6 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: arithmetic average roughness of the surface of the diamond film at the second portion is 0.013 μm or less. ‘Kelly does not teach a specific roughness. However, ‘Kelly does teach: Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish. It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish of the diamond coated mandrel to 0.013 μm 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). Regarding Claim[s] 7 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: arithmetic average roughness of the surface of the diamond film at the first portion is 0.023 μm or less, and the arithmetic average roughness of the surface of the diamond film at the second portion is 0.013 μm or less. ‘Kelly does not teach a specific roughness. However, ‘Kelly does teach: Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish. It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish of the diamond coated mandrel to 0.023 μm or less and the surface finish of the second portion of the diamond coating to 0.013 μm 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). Regarding Claim[s] 10 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: tube expansion step, the outside diameter of the circular heat transfer tube is increased to 104% or more and 112% or less of the outside diameter of the circular heat transfer tube before the tube expansion step. However, it would have been obvious to one having ordinary skill in the art at the time the invention was made to expand the outside diameter of the circular heat transfer tube to between 104% to 112% before the expansion step. Expanding before the expansion step and then expanding again would be considered changes in size or sequence of adding ingredients (2144.04 IV C). Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959) (Prior art reference disclosing a process of making a laminated sheet wherein a base sheet is first coated with a metallic film and thereafter impregnated with a thermosetting material was held to render prima facie obvious claims directed to a process of making a laminated sheet by reversing the order of the prior art process steps.). See also In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946) (selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results); In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930) (Selection of any order of mixing ingredients is prima facie obvious.). Claim 2, 11 – 13 & 16 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), and in view of U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter), and in further view of U.S. 2022/0412669 Harata et al. (‘Harata hereafter). Regarding Claim[s] 2 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: circular heat transfer tube is aluminum or aluminum alloy, and the circular heat transfer tube has grooves in an inner surface thereof. However, ‘Harata does teach: Para 0053, “The inner spiral grooved tube 2 in the present embodiment is a twisted material of the extruded raw tube described below. The inner spiral-grooved tube 2 can be made of aluminum or an aluminum alloy. When an aluminum alloy is used for the inner spiral grooved tube 2, there are no restrictions on the aluminum alloy to be used. Pure aluminum alloys defined by JIS, such as 1050 series, 1100 series, 1200 series and the like can be used. Alternatively, aluminum alloys of 3000 series represented by 3003 series, to which Mn is added, and the like can be used. In addition, the inner spiral grooved tubes 2 may be constituted by using any one of other aluminum alloys of 5000 to 7000 series defined by JIS.” Hence, it would have been obvious to one of ordinary skill in the art at the effective filing date of the claimed invention to provide ‘Kelly with a spiral grooved aluminum alloy tube as taught by ‘Harata in order to provide an excellent heat transfer property and a heat exchanger (‘Harata, Para 0001). Regarding Claim[s] 11, ‘Milliman discloses all the claim limitations including: A method for manufacturing a heat exchanger (‘Milliman, Para 0001, “This invention relates to a tube pressure expansion device and, more particularly, a device that is adapted to pressure-expand plural tubes embodied in a workpiece coil at the same time.” Para 0004, “The objects and purposes of the invention are met by providing a tube pressure expansion device for expanding plural hollow tubes on a workpiece coil having plural fins. Each hollow tube has an open free end to an interior thereof. A pressure expansion manifold has plural cavities each configured to receive a free end of a respective tube on the workpiece coil. An interior wall surface in each cavity includes a tube seating wall surface. A hollow bullet is provided in each cavity and is configured for entering the tube opening at each free end for effecting an expansion of each free end to urge the material of each free end into a clamped and sealed relation with the tube seating wall surface in each said cavity. Plural passageways are provided in the pressure expansion manifold and each are configured to supply a pressurized fluid to an interior of each of the hollow bullets to effect a pressurization of the interior of each of the tubes to effect an expansion of the tubes into an interference fit with the fins on the workpiece coil.” Discusses applicant’s advantages of their invention for the manufacturing of a heat exchanger), the heat exchanger comprising a plateshaped fin (‘Milliman, #WC (workpiece coil/ heat exchanger), #F (sheet metal fins/ plate-shaped fins)) and a circular heat transfer tube, the method comprising: inserting the circular heat transfer tube (‘Milliman, Fig 4A2, shows #T (U-Shaped tubes) that are straight tube bent into a “U” shape, and #CE (cylindrical end)) through a through hole in the plate-shaped fin (‘Milliman, Fig 4A2, shows tube through #F (sheet metal plate); and expanding an outside diameter of the inserted circular heat transfer tube and fixing the plateshaped fin to the circular heat transfer tube (‘Milliman, Fig 6A1, shows #10 (tube pressure expander device), #36 (piston), #T (U-shaped tube), #39 (tapered bullet), #37 (piston rod), Para 0044, teaches the expansion of the outside diameter of the heat transfer tube #T), wherein the expanding of the outside diameter comprises pushing a tube expansion plug into the circular heat transfer tube and increasing the outside diameter of the circular heat transfer tube (‘Milliman, Fig 6A1, #39 (tapered bullet) is an expansion plug pushed into the tube #T, and thereby increasing the outside diameter of the tube), Except ‘Milliman is silent regarding: wherein the tube expansion plug comprises a plug body made of a cemented carbide and a diamond film configured to cover a surface of the plug body, However, ‘Kelly teaches: wherein the tube expansion plug comprises a plug body made of a cemented carbide and a diamond film configured to cover a surface of the plug body (‘Kelly, Para 0040, “[0040] In a subsequent rotary forging process, the barrel blanks may essentially be extruded from a diameter of 7.87 mm down to a final 5.56 mm diameter. In this process, a solid carbide die is placed inside the barrel. This die has the rifling machined into it, and the rifling is then transferred to the barrel as the extrusion takes place. The forging mandrel is sized to produce a final rifled dimension on the coated blanks after forging. Tungsten carbide mandrels may be treated with a diamond coating to provide wear resistance during the rotary forging operation. The coated barrels may be subjected to destructive evaluation in order to verify the metallurgical bond, as well as other properties of the coatings. FIG. 5 is a micrograph of a gun barrel cross section after rotary forging and extrude-honing.”). Hence, it would have been obvious to one of ordinary skill in the art at the effective filing date of the claimed invention to provide ‘Milliman with a Tungsten Carbide mandrel expansion tool with a diamond coating as taught by ‘Kelley in order to provide wear resistance during the operation of the expansion (‘Kelly, Para 0040). Except ‘Milliman is silent regarding: the circular heat transfer tube is aluminum or aluminum alloy, the circular heat transfer tube has grooves in an inner surface thereof, However, ‘Harata does teach: Para 0053, “The inner spiral grooved tube 2 in the present embodiment is a twisted material of the extruded raw tube described below. The inner spiral-grooved tube 2 can be made of aluminum or an aluminum alloy. When an aluminum alloy is used for the inner spiral grooved tube 2, there are no restrictions on the aluminum alloy to be used. Pure aluminum alloys defined by JIS, such as 1050 series, 1100 series, 1200 series and the like can be used. Alternatively, aluminum alloys of 3000 series represented by 3003 series, to which Mn is added, and the like can be used. In addition, the inner spiral grooved tubes 2 may be constituted by using any one of other aluminum alloys of 5000 to 7000 series defined by JIS.” Hence, it would have been obvious to one of ordinary skill in the art at the effective filing date of the claimed invention to provide ‘Kelly with a spiral grooved aluminum alloy tube as taught by ‘Harata in order to provide an excellent heat transfer property and a heat exchanger (‘Harata, Para 0001). ‘Milliman and ‘Kelly are silent regarding: an arithmetic average roughness of a surface of the diamond film of the tube expansion plug is 0.023 μm or less. However, ‘Kelly does not teach a specific roughness. However, ‘Kelly does teach: Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish. It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish of the diamond coated mandrel to 0.023 μm 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 Bosch, 617 F, 2d 272, 205 USPQ 215 (CCPA 1980). Regarding Claim[s] 12, ‘Millman, ‘Kelley and ‘Harata discloses all the claim limitations including: wherein the tube expansion plug has a base end and a distal end (‘Milliman, Fig 6A1, #39 (tapered bullet/ expansion plug) shows a distal end, Fig 5C1 shows #39 with a base end), and the tube expansion plug comprises: a first portion disposed between the base end and the distal end and at which the tube expansion plug has a largest outside diameter (‘Milliman, Fig 5C1); an enlarged diameter portion disposed from the distal end to the first portion and that has an outside diameter that increases gradually from the distal end toward the first portion (‘Milliman, Fig 5C1); and a second portion disposed within the enlarged diameter portion and that has an outside diameter equal to an inside diameter of the circular heat transfer tube before the tube expansion step (‘Milliman, Fig 5C1, shows #39 (tapered bullet. Expansion plug) fits into the tube diameter partially before the pressure is applied to expand the end tube diameter), and an arithmetic average roughness of a surf ace of the diamond film at the second portion is lower than an arithmetic average roughness of a surface of the diamond film at the first portion (‘Kelly, Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish.) It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish after the expansion to have a second portion of a lower roughness that the surface of the diamond portion, 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). Regarding Claim[s] 13, ‘Millman, ‘Kelley and ‘Harata discloses all the claim limitations including: wherein the arithmetic average roughness of the surface of the diamond film at the first portion is 0.023 μm or less, and the arithmetic average roughness of the surface of the diamond film at the second portion is 0.013 μm or less. ‘Kelly does not teach a specific roughness. However, ‘Kelly does teach: Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish. It would have been obvious to one having ordinary skill in the art at the time the invention was made to manufacture the surface finish of the diamond coated mandrel to 0.023 μm or less and the surface finish of the second portion of the diamond coating to 0.013 μm 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). Regarding Claim[s] 16, ‘Millman, ‘Kelley and ‘Harata discloses all the claim limitations except is silent regarding: wherein, in the tube expansion step, the outside diameter of the circular heat transfer tube is increased to 104% or more and 112% or less of the outside diameter of the circular heat transfer tube before the tube expansion step. However, it would have been obvious to one having ordinary skill in the art at the time the invention was made to expand the outside diameter of the circular heat transfer tube to between 104% to 112% before the expansion step. Expanding before the expansion step and then expanding again would be considered changes in size or sequence of adding ingredients (2144.04 IV C). Ex parte Rubin, 128 USPQ 440 (Bd. App. 1959) (Prior art reference disclosing a process of making a laminated sheet wherein a base sheet is first coated with a metallic film and thereafter impregnated with a thermosetting material was held to render prima facie obvious claims directed to a process of making a laminated sheet by reversing the order of the prior art process steps.). See also In re Burhans, 154 F.2d 690, 69 USPQ 330 (CCPA 1946) (selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results); In re Gibson, 39 F.2d 975, 5 USPQ 230 (CCPA 1930) (Selection of any order of mixing ingredients is prima facie obvious.). Claim 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), and in view of U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter), and in further view of U.S. 2012/0055014 Branyon et al. (‘Branyon hereafter). Regarding Claim[s] 8 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: lubricant to an inner surface of the circular heat transfer tube before the tube expansion step, wherein an amount of the lubricant applied to the inner surface of the circular heat transfer tube in the application step is less than 0.5 g per meter of a length of the circular heat transfer tube. However, ‘Branyon does teach: Para 0028, “The objects above as well as the other features of the invention are realized in an improved method for manufacturing mechanically assembled aluminum tube and fin heat exchangers that, according to the preferred embodiment, includes a process for applying an ashless lubricant to the tube wall prior to the final expansion of the tube. The lubrication application reduces the amount of force required for final expansion and reduces the resultant distortion (rifling) to the internal tube geometry. It would have been obvious to one having ordinary skill in the art at the time the invention was made to apply an amount lubricant to less than 0.5 g per meter of a length of the circular heat transfer tube, 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). Claim 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), and in view of U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter), and in further view of U.S. 5,644,841 Stewart et al. (‘Stewart hereafter). Regarding Claim[s] 9 ‘Milliman and ‘Kelly discloses all the claim limitations except is silent regarding: tube expansion step is performed with no lubricant applied to an inner surface of the circular heat transfer tube. However, ‘Stewart does teach: (‘Stewart, Col. 9, ln 5 – 21, “A return bend header 86 having a plurality of openings alignable with the fin openings is laced onto distal ends 80d of each hairpin 80 such that return bend header 86 is in opposed relationship with hairpin header 82. A tube expander 88 expands the diameter of each hairpin 80 by 10 approximately 0.004 to 0.008 inch larger than its pre-expanded diameter, thereby locking hairpins 80 into fins 68. No additional lubricant is added to hairpins 80 during the expansion operation because of the 0.110 cubic centimeters of lubricant per hairpin limitation. Without additional lubricant during the expansion operation, hairpin shrinkage will be greater than if additional lubricant were applied. Therefore, hairpins 80 must be made slightly longer than the hairpins used in prior art processes where additional lubricant is applied prior to expansion. Further, excessive shrinkage of hairpins 80 during expansion without additional lubricant may require the tips of tube expander 88 to be reduced in diameter by approximately 0.001 to 0.002 inch.”). Hence, it would have been obvious to one of ordinary skill in the art at the effective filing date of the claimed invention to provide ‘Milliman with a tube expansion step without lubrication as taught by ‘Stewart in order to provide a lock of the tubes with the coil fins (‘Stewart, Col. 9, ln 5 – 21). Claim 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), and in view of U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter), and in view of U.S. 2022/0412669 Harata et al. (‘Harata hereafter), and in further view of U.S. 2012/0055014 Branyon et al. (‘Branyon hereafter). Regarding Claim[s] 14, ‘Millman, ‘Kelley and ‘Harata discloses all the claim limitations except is silent regarding: applying a lubricant to an inner surface of the circular heat transfer tube before the tube expansion step, wherein an amount of the lubricant applied to the inner surface of the circular heat transfer tube in the application step is less than 0.5 g per meter of a length of the circular heat transfer tube. However, ‘Branyon does teach: Para 0028, “The objects above as well as the other features of the invention are realized in an improved method for manufacturing mechanically assembled aluminum tube and fin heat exchangers that, according to the preferred embodiment, includes a process for applying an ashless lubricant to the tube wall prior to the final expansion of the tube. The lubrication application reduces the amount of force required for final expansion and reduces the resultant distortion (rifling) to the internal tube geometry. It would have been obvious to one having ordinary skill in the art at the time the invention was made to apply an amount lubricant to less than 0.5 g per meter of a length of the circular heat transfer tube, 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). Claim 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over U.S. 2013/0213105 James G. Milliman (‘Milliman hereafter), and in view of U.S. 2004/0140292 Kelly et al. (‘Kelly hereafter), and in view of U.S. 2022/0412669 Harata et al. (‘Harata hereafter), and in further view of U.S. 5,644,841 Stewart et al. (‘Stewart hereafter). Regarding Claim[s] 15, ‘Millman, ‘Kelley and ‘Harata discloses all the claim limitations except is silent regarding: wherein the tube expansion step is performed with no lubricant applied to an inner surface of the circular heat transfer tube. However, ‘Stewart does teach: (‘Stewart, Col. 9, ln 5 – 21, “A return bend header 86 having a plurality of openings alignable with the fin openings is laced onto distal ends 80d of each hairpin 80 such that return bend header 86 is in opposed relationship with hairpin header 82. A tube expander 88 expands the diameter of each hairpin 80 by 10 approximately 0.004 to 0.008 inch larger than its pre-expanded diameter, thereby locking hairpins 80 into fins 68. No additional lubricant is added to hairpins 80 during the expansion operation because of the 0.110 cubic centimeters of lubricant per hairpin limitation. Without additional lubricant during the expansion operation, hairpin shrinkage will be greater than if additional lubricant were applied. Therefore, hairpins 80 must be made slightly longer than the hairpins used in prior art processes where additional lubricant is applied prior to expansion. Further, excessive shrinkage of hairpins 80 during expansion without additional lubricant may require the tips of tube expander 88 to be reduced in diameter by approximately 0.001 to 0.002 inch.”). Hence, it would have been obvious to one of ordinary skill in the art at the effective filing date of the claimed invention to provide ‘Milliman with a tube expansion step without lubrication as taught by ‘Stewart in order to provide a lock of the tubes with the coil fins (‘Stewart, Col. 9, ln 5 – 21). Response to Arguments Applicant's arguments filed 12/22/2025 have been fully considered but they are not persuasive. Applicant’s remarks Pg 9, discusses a preparation step, a tube insertion step, a tube expansion step, a drying step, a brazing step, and a testing step, as shown in FIG. 4. However, drying, brazing, and testing are not claimed in the original or current claim amendment. Applicant’s arguments Pg 12, “Milliman is silent with respect to the outer surfaces of the tubes T expanded by the tube expansion plug being brought into tight contact with the fins F. However, ‘Milliman does teach: Figs 4A2, 5A1, 5B1, 5B2, 5C1, 5C2, 6A1, 6A2, 7A1, 7A2, 8, 8A, Show #F (sheet metal fins/ fins) and #T (U-shaped tubes/ heat transfer tube) in an assembled system, Abst teaches: “A pressurized fluid is supplied to an interior of the hollow tapered bullet to effect a pressurization of the interior of the tubes to effect an expansion of the tubes into an interference fit with the fins on the workpiece coil.” Interference Fit is a tight contact.” Applicant argues that claim 11 limitations regarding an average roughness of a surface of the diamond film of the tube expansion plug is 0.023 micrometer or less, and that a POSITA would not discover an optimum value of a result effective variable. However, ‘Kelly does teach: Para 0007, “The present invention provides an improved method for the deposition of protective coatings directly to the inner wall of a gun barrel, including smooth-bored and rifled barrel designs. The coated surfaces are produced by micro-welding techniques, such as electro-spark deposition, pulse-fusion and the like. The deposited coatings are then surface treated by working methods such as forging and/or honing to provide the desired surface finish. Further, Applicant Para 0071 - 0072, Spec 03/13/2025 recites: Table 1, where Applicant indeed derived the range of 0.013 to 0.023 micrometer of roughness through effective results of experimentation. A POSITA would find the desired finish for adhesion the same way as Applicant’s experiment in Table 1. Conclusion Examiner encourages Applicant to fill out and submit form PTO-SB-439 to allow internet communications in accordance with 37 CFR 1.33 (MPEP 02.03). Should the need arise to perfect applicant-proposed or examiner’s amendments, authorization for e-mail correspondence would have already been authorized and would save time. 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 LAWRENCE AVERICK whose telephone number is (571)270-7565. The examiner can normally be reached 8:00AM - 3:00PM M- F ET. 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, Thomas Hong can be reached at 571-272-0993. 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. /LAWRENCE AVERICK/ Primary Examiner, Art Unit 3799 02/03/2026
Read full office action

Prosecution Timeline

Mar 13, 2025
Application Filed
Sep 25, 2025
Non-Final Rejection — §103
Dec 22, 2025
Response Filed
Feb 03, 2026
Final Rejection — §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12601449
Methods for Assembling a Multi-Conic Preform and Manufacturing a Semi-Ellipsoidal Shell Using the Multi-Conic Preform
2y 5m to grant Granted Apr 14, 2026
Patent 12600494
MANUFACTURING FACILITY AND METHOD
2y 5m to grant Granted Apr 14, 2026
Patent 12594653
SYSTEM AND METHOD FOR INSTALLING A MANIFOLD PLUG
2y 5m to grant Granted Apr 07, 2026
Patent 12589455
SEAL REMOVAL JIG, SEAL REMOVAL METHOD, AND SEAL PORTION
2y 5m to grant Granted Mar 31, 2026
Patent 12583035
COMBINED PROCESSING MACHINE
2y 5m to grant Granted Mar 24, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

3-4
Expected OA Rounds
76%
Grant Probability
99%
With Interview (+23.6%)
2y 10m
Median Time to Grant
Moderate
PTA Risk
Based on 658 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month