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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/23/2026 has been entered.
Status of the Claims
In the amendment dated 02/18/2026, claims 1-4 are pending.
Claim 1 has been amended.
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 factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Esibian (US 4059743 A) in view of Kitahashi (US 5726414 A, newly cited)
Regarding claim 1, Esibian discloses
A modified cathode device (combo 1-2, see figs.1-2) adapted for use in a plasma arc spray gun (plasma arc torch, see title and fig.1), said modified cathode device (combo 1-2, see figs.1-2) comprising: a central longitudinal axis (see central longitudinal axis in annotated fig.1 below) traversing the modified cathode device (combo 1-2) from a first end to a second end (see first end and send end in annotated fig.1 below)
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Annotated figs. 1-2 of Esibian
a partially dome-shaped portion (22, see fig.2), said partially dome-shaped portion (22, see fig.2) having rounded edges (see fig.2), said rounded edges (22, see fig.2) terminating as a flat surface (20, see fig.2) along the first end (see first end in annotated fig.1 above) of the modified cathode device (combo 1-2), said flat surface (20, see fig.2) characterized by a width (width of 20) extending from a first edge of the flat surface to a second edge of the flat surface (see first and second edges of the flat surface 20 annotated fig.2 above) and a midpoint (see midpoint in annotated fig.2 above) located between the first edge and the second edge (see first and second edges of the flat surface annotated fig.2 above), wherein the midpoint (see midpoint in annotated fig.2 above) of the flat surface (20, see fig.2) is located along the central longitudinal axis (see central longitudinal axis in annotated figs.1-2 above) of the modified cathode device (combo 1-2); and
a body portion (1, see figs.1-2) extending from the partially dome-shaped portion (22) to the second end of the modified cathode device (See the annotated second end of the combo 1-2 in fig.1 above) .
Esibian discloses said partially dome-shaped portion 22 (See fig.2), but Esibian does not expressly disclose said partially dome-shaped portion being a partially spherical structure.
However, Kitahashi discloses an electrode for use in a plasma torch, comprising:
said partially dome-shaped portion (forward end portion, see fig.6A) being a partially spherical structure having rounded edges (See fig.6A and col.7, lines 21-22: “As shown in FIG. 6A, an electrode 3' had a forward end that was contoured in a spherical configuration”).
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At the time the invention was made, it would have been obvious mater of design choice to a person of ordinary skill in the art to modify said partially dome-shaped portion of Esibian to be “a partially spherical structure” as taught by Kitahashi (Notes: the modification does not affect to the flat surface 20 of Esibian), because applicant has not disclosed that the shape “a partially spherical structure” provides an advantage is used for particular purpose or solves a stated problem. One of ordinary skill in the art would have expected the Applicant' s invention to perform equally well with Kitahashi’s shape or Esibian’s shape, because both shapes perform the function of generating the plasma arc equally well (MPEP 2144.04 IV B)
Regarding claim 2, Esibian further discloses said flat surface (20, see fig.2) is
sufficient to stabilize an arc along a central portion (See central portion in annotated fig.2 below) between the first edge and the second edge of the flat surface ( see first and second edges of the flat surface annotated fig.2 below and col.6, lines 47-50: “ a pilot arc is established between the electrode 1 and the nozzle 3 in the gap 19 to draw the cutting arc between the electrode 1 and the metal being treated”).
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Annotated fig.2 of Esibian
Regarding claim 3, Esibian further discloses the rounded edges (22, see fig.2) have a
degree of curvature represented by a radius (R, see fig.2) of .1 inches to .3 inches (see fig.2 and col.6 lines 28-39, R=3cm (=0.118 inches) or 5 mm (=0.197 inches), which is within the claimed ranges).
Regarding claim 4, Esibian further discloses the second end (see second end in
annotated fig. 1 above) of the body portion (1, see fig.1-2) is configured to be operably connected to a cathode holder ( electrode holder 4 , see fig.1).
Response to Arguments
Applicant’s arguments, see Remarks, filed on 02/18/2026, with respect to the rejection(s) of claim(s) 1 under 102 rejections have been fully considered and are persuasive in light of amendments. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made by the modification of Esibian in view of Kitahash, wherein Kitahash teaches the amended limitation: “said partially dome-shaped portion being a partially spherical structure” is taught by Kitahash.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., “the "partially dome-shaped portion" of claim 1 requires the center of the circular shape of the cathode device to be located along the "central longitudinal axis of the cathode”, see page 3, Remarks) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
For the above reasons, rejection to claim 1 is respectfully sustained.
Claims 2-4 are rejected by the virtue of the dependency upon claim 1.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
US 5444209 A discloses the cathode assembly 155 has a cylindrical surface 189. Downstream of the cylindrical surface 189 of the tip 157 is a frusto-conical surface 191. The apex end of the frusto-conical surface 191 blends into the spherical end 179 of the tip 157 (see fig.4).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TIFFANY T TRAN whose telephone number is (571)272-3673. The examiner can normally be reached on Monday - Friday, 10am - 6pm.
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/TIFFANY T TRAN/ Primary Examiner, Art Unit 3761