Prosecution Insights
Last updated: October 27, 2026
Application No. 18/688,845

ARC EXTINGUISHING CHAMBER, VACUUM CIRCUIT BREAKER, AND METHOD OF ASSEMBLING ARC EXTINGUISHING CHAMBER

Final Rejection §102
Filed
Mar 04, 2024
Priority
Nov 08, 2021 — nonprovisional of PCTJP2021040985
Examiner
BOLTON, WILLIAM A
Art Unit
2831
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Mitsubishi Electric Corporation
OA Round
2 (Final)
89%
Grant Probability
Favorable
3-4
OA Rounds
0m
Est. Remaining
95%
With Interview

Examiner Intelligence

Grants 89% — above average
89%
Career Allowance Rate
696 granted / 779 resolved
+21.3% vs TC avg
Moderate +6% lift
Without
With
+5.7%
Interview Lift
resolved cases with interview
Fast prosecutor
1y 10m
Avg Prosecution
26 currently pending
Career history
813
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
54.6%
+14.6% vs TC avg
§102
30.3%
-9.7% vs TC avg
§112
10.6%
-29.4% vs TC avg
Black line = Tech Center average estimate • Based on career data from 779 resolved cases

Office Action

§102
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 . Response to Amendment The Amendment filed August 4th, 2026 has been entered. Claims 1-7 are pending. 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 5 is rejected under 35 U.S.C. 102 (a)(1) as being anticipated by Nagatake et al, JP2013058312 [Nagatake]. Regarding claim 5, in order to assemble and use the device, Nagatake would necessarily have performed most of the claimed method of assembling an arc extinguishing chamber (2), comprising: a vacuum interrupter (2) including: a movable contact point (3) and a stationary contact point (4); a movable lead (5) electrically connected to the movable contact point (3); a stationary lead (6) electrically connected to the stationary contact point (4); a vacuum container (2) accommodating the movable contact point (3), the stationary contact point (4), and the stationary lead (6) and from one end of which the movable lead (5) protrudes outward; and a bellows (8) connecting the vacuum container (2) and the movable lead (5) to each other, the bellows (8) configured to extend in a closed state in which the movable contact point (3) and the stationary contact point (4) are in contact with each other, and configured to contract in an open state in which the movable contact point (3) and the stationary contact point (4) are separated from each other; a contact case (9) having a tubular shape and made of a conductive material; a contact (15) fixed to an end of the movable lead (5), disposed inside a tube of the contact case (9), and electrically connecting the contact case (9) and the movable lead (5) to each other; a seal rod connected to the movable lead (5) and configured to cause the movable lead (5) to move; and a movable-side support (10) having a cylinder shape with a bottom surface in which a hole through which the seal rod passes is formed, the method comprising a step of coupling the contact case (9) and the movable-side support (10) in the open state. Allowable Subject Matter Claims 1-4 and 6-7 are allowed. Applicant's arguments filed August 4th, 2026 were fully considered and are persuasive. The following is an examiner’s statement of reasons for allowance: Regarding claim 1, the prior art fails to teach or show, alone or in combination, the claimed An arc extinguishing chamber comprising a vacuum interrupter including an air pressure inside a closed space surrounded and sealed by the bellows, the contact case, and the movable-side support, so as not to cause inflow and outflow of a gas accompanying extension and contraction of the bellows, is atmospheric pressure in the open state, and is less than atmospheric pressure in the closed state. Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.” Response to Arguments Applicant's arguments filed August 4th, 2026 in regard to claim 5, have been fully considered but they are not persuasive. Applicant argues that Nagatake does not disclose or suggest an arc extinguishing chamber, which includes coupling the contact case and the movable-side support in the open state. Examiner cannot concur with the Applicant, because Nagatake clearly discloses an arc extinguishing chamber (2), which includes coupling the contact case (9) and the movable-side support (10) in an open state, which is functionally and structurally equivalent to Applicant’s claimed limitations, and therefore satisfies all claimed limitations, as recited. Examiner further notes, that it is only logical that Nagatake’s contact case and movable-side support are physically connected, and regardless of whether in the open state or a closed state, will always be connected to each other, thus further meeting the requirement of the claimed invention. Conclusion THIS ACTION IS MADE FINAL. Applicants are 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 WILLIAM A BOLTON whose telephone number is (571)270-5887. The examiner can normally be reached Mon-Fri: 7:30AM - 5:00PM. 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, Renee S Luebke can be reached at 571-272-2009. 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. /WILLIAM A BOLTON/Primary Examiner, Art Unit 2831
Read full office action

Prosecution Timeline

Mar 04, 2024
Application Filed
Apr 03, 2026
Non-Final Rejection (signed) — §102
May 04, 2026
Non-Final Rejection mailed — §102
Aug 04, 2026
Response Filed
Oct 01, 2026
Final Rejection mailed — §102 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12770811
VACUUM INTERRUPTER AND ARRANGEMENT COMPRISING VACUUM INTERRUPTERS, AND METHOD FOR TURNING OFF VACUUM INTERRUPTERS
2y 9m to grant Granted Oct 20, 2026
Patent 12763275
SWITCHING DEVICE
2y 11m to grant Granted Oct 13, 2026
Patent 12755911
Switch for a Medium Voltage or High Voltage Switchgear
2y 11m to grant Granted Oct 06, 2026
Patent 12755912
ARRANGEMENT AND METHOD FOR AUTOMATICALLY CONFIGURING A MAGNETIC DRIVE
2y 9m to grant Granted Oct 06, 2026
Patent 12749637
OVERMOLDED ELECTRICAL DEVICE WITH LOW ELECTRICAL STRESS PARTING LINES
2y 8m to grant Granted Sep 29, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

Strategy Recommendation AI-generated — please review before filing

Get a prosecution strategy drawn from examiner precedents, rejection analysis, and claim mapping.
Typically takes 5-10 seconds — AI-generated, attorney review required before filing

Prosecution Projections

3-4
Expected OA Rounds
89%
Grant Probability
95%
With Interview (+5.7%)
1y 10m (~0m remaining)
Median Time to Grant
Moderate
PTA Risk
Based on 779 resolved cases by this examiner. Grant probability derived from career allowance 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