Prosecution Insights
Last updated: April 17, 2026
Application No. 17/799,512

Combustion Device

Non-Final OA §102§103
Filed
Aug 12, 2022
Examiner
LAUX, DAVID J
Art Unit
3762
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
unknown
OA Round
1 (Non-Final)
65%
Grant Probability
Moderate
1-2
OA Rounds
3y 1m
To Grant
93%
With Interview

Examiner Intelligence

Grants 65% of resolved cases
65%
Career Allow Rate
543 granted / 838 resolved
-5.2% vs TC avg
Strong +29% interview lift
Without
With
+28.6%
Interview Lift
resolved cases with interview
Typical timeline
3y 1m
Avg Prosecution
19 currently pending
Career history
857
Total Applications
across all art units

Statute-Specific Performance

§101
0.7%
-39.3% vs TC avg
§103
49.7%
+9.7% vs TC avg
§102
17.4%
-22.6% vs TC avg
§112
25.8%
-14.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 838 resolved cases

Office Action

§102 §103
DETAILED ACTION Application Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . This action is in response to Applicant’s submission dated 08/12/2022 & 11/20/2025. Claim(s) 18–37 are pending. Election/Restrictions Applicant’s election without traverse of Group I: claims 18–31 in the reply filed on 11/20/2025 (and re-elected in the telephone interview on 12/08/2025) is acknowledged. Claim Objections Claim 29 is objected to because of the following informalities: the claim includes a range of one of: 1) >30 mins; or 2) >60 mins. Effectively, the claim is claiming a range of >30 mins since >60 mins is included within >30 mins, which makes the claim limitation confusing. Appropriate correction is required. Claim 30 is objected to because of the following informalities: on line 2, “another” has been misspelled “an other.” Appropriate correction is required. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention. Claim(s) 18–20, 22, & 27–28 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by US 4,460,377 to Kalil. With regard to claim 18, Kalil discloses a combustion device for burning a fuel (abstract), wherein the combustion device (10) comprises a first chamber (the portion of combustion device (10) above the divider (38)) and a second chamber (30) (Fig. 1), wherein the second chamber (30) is arranged underneath the first chamber (the portion of combustion device (10) above the divider (38)) and the first chamber (the portion of combustion device (10) above the divider (38)) receives the fuel (Col. 2, lines 14–21; Fig. 1), wherein the first chamber (the portion of combustion device (10) above the divider (38)) comprises an intermediate layer (38) positioned at a bottom of the first chamber (the portion of combustion device (10) above the divider (38)) (Fig. 1; Col. 2, lines 7–9), the intermediate layer (38) comprising a combustible material which holds the fuel in the first chamber (the portion of combustion device (10) above the divider (38)) until the intermediate layer (38) is damaged or destroyed by combustion (Fig. 1; Col. 2, lines 32–40), wherein when the intermediate layer (38) is damaged or destroyed, fuel located in the first chamber (the portion of combustion device (10) above the divider (38)) falls into the second chamber (30) (Fig. 1; Col. 2, lines 32–40), wherein, the combustion in the first chamber (the portion of combustion device (10) above the divider (38)) comprises gas combustion (Col. 2, lines 32–40, 60–65; fuel is inherently heated by combustible ignition material, which drives off volatile gases that would be burned in the first chamber) and, wherein after the fuel has been conveyed into the second chamber (30), the fuel is either burned or may be removed from the second chamber through an opening, wherein the removed fuel comprises charcoal (Col. 2, lines 32–40). With regard to claim 19, Kalil further discloses the fuel comprises wood (Col. 2, lines 14–20). With regard to claim 20, Kalil further discloses the charcoal comprises one of vegetable coal and biochar (Col. 2, lines 14–20; partially combusted wood, which is used as the fuel, creates biochar). With regard to claim 22, Kalil further discloses the first chamber (the portion of combustion device (10) above the divider (38)) is designed so that a container (“combustible wrapping material” is considered a “container”) containing the fuel is insertable from above (Col. 2, lines 14–20). With regard to claim 23, Kalil further discloses the intermediate layer forms the bottom of the container which is insertable into the first chamber (the portion of combustion device (10) above the divider (38)) (Col. 2, lines 14–20). With regard to claim 27, Kalil further discloses an outer side of the container (“combustible wrapping material” is considered a “container”) consists of one of paper, cardboard, paper strips, and a web of natural fibers (Col. 2, lines 14–20). With regard to claim 28, Kalil further discloses the intermediate layer (38) consists of one or more layers of cardboard, paper fiber, and/or wood (Col. 1, line 63–Col. 2, line 9). 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. Claims 21 & 30 are rejected under 35 U.S.C. 103 as being unpatentable over Kalil in view of US 10,327,590 to Moore et al. With regard to claim 21, Kalil fails to disclose a support for holding the intermediate layer is formed at a bottom end of the first chamber. Moore teaches a support (141, 174, 179, 188) for holding the intermediate layer (142, 180) is formed at a bottom end of the first chamber (200) (Col. 6, lines 1–7, 47–50). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to combine the combustion device of Kalil with the intermediate layer supports of because such a combination would have had the added benefit of Moore because doing so would have allowed the intermediate layer to be raised to a higher height, providing more room in the lower chamber. With regard to claim 30, Kalil further discloses the first (the portion of combustion device (10) above the divider (38)) and/or second (30) chambers are arranged vertically one above another and have, at least at a transition between the first (the portion of combustion device (10) above the divider (38)) and second (30) chamber, an approximately identical cross-section which comprises a shape that is one of a circle, a square, a rectangle, and an oval (Fig. 1). Kalil fails to disclose a means for holding the intermediate layer consists of one of a protrusion, an edge, pins, and bolts pointing from the outside into an interior space of the first chamber. Moore teaches a means for holding the intermediate layer consists of one of a protrusion, an edge, pins, and bolts pointing from the outside into an interior space of the first chamber (Col. 6, lines 1–7, 47–50). It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to combine the combustion device of Kalil with the intermediate layer supports of because such a combination would have had the added benefit of Moore because doing so would have allowed the intermediate layer to be raised to a higher height, providing more room in the lower chamber. Claims 24–25 & 29 are rejected under 35 U.S.C. 103 as being unpatentable over Kalil. With regard to claim 24, Kalil further discloses a firelighter (44) is arranged in the combustion device (10) (Fig. 1; Col. 2, lines 17–20). Kalil fails to disclose the firelighter is arranged on a top side of the container. It would have been obvious to one having ordinary skill in the art at the time the invention was made to install the firelighter on a top side of the container, since to shift the location of parts of a device involves only routine skill in the art. In re Japikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950) (Claims to a hydraulic power press which read on the prior art except with regard to the position of the starting switch were held unpatentable because shifting the position of the starting switch would not have modified the operation of the device.); In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975) (the particular placement of a contact in a conductivity measuring device was held to be an obvious matter of design choice). With regard to claim 25, Kalil further discloses the container forms one of a sack, a bag, and a packet, each of which has the intermediate layer at the bottom of the first chamber (Col. 2, lines 14–20; “combustible wrapping material” is considered a “container”), and above that has the fuel in a form of a wood (Col. 2, lines 14–20), wherein the container is closed at the top side (Fig. 1). Kalil fails to disclose the firelighter being arranged above the fuel. It would have been obvious to one having ordinary skill in the art at the time the invention was made to install the firelighter above the fuel, since to shift the location of parts of a device involves only routine skill in the art. In re Japikse, 181 F.2d 1019, 86 USPQ 70 (CCPA 1950) (Claims to a hydraulic power press which read on the prior art except with regard to the position of the starting switch were held unpatentable because shifting the position of the starting switch would not have modified the operation of the device.); In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975) (the particular placement of a contact in a conductivity measuring device was held to be an obvious matter of design choice). With regard to claim 29, Kalil fails to disclose the container is assembled so that a predetermined combustion duration is defined, wherein the combustion duration is one of more than 30 minutes and 60 minutes or more. However, combustion duration is a product of the amount of fuel and oxygen that can be combined at a given rate. Modifying variables, such as increasing the amount of fuel and/or oxygen or limiting the amount of fuel that can interact with the oxygen can drastically affect the combustion duration, as is old and well-known in the art. Therefore, It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to adjust the amount of fuel and/or oxygen or the rate at which the fuel interacts with the oxygen to produce a device with a combustion duration of over 30 minutes Claim 31 is rejected under 35 U.S.C. 103 as being unpatentable over Kalil in view of US 3,884,214 to Duncan. Kalil fails to disclose the intermediate layer of combustible material is held in place by a slide-in insert, said slide-in insert being insertable into an opening of the combustion device, said opening being located between the first chamber and the second chamber. Duncan teaches a slide-in insert (14, 28) for supporting fuel (40) (Figs. 5 & 6; Col. 2, lines 13–24), said slide-in insert (14, 28) being insertable into an opening (22) of the combustion device (Figs. 5 & 6; Col. 2, lines 13–24), said opening being located between the first chamber and the second chamber (Figs. 5 & 6; Col. 2, lines 13–24). Allowable Subject Matter Claim 26 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: see attached PTO-892. Applicant is encouraged to review the cited references prior to submitting a response to this office action. Any inquiry concerning this communication or earlier communications from the examiner should be directed to DAVID J LAUX whose telephone number is (571)270-7619. The examiner can normally be reached 8:30-5:30 M-F. 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, Edelmira Bosques can be reached at (571) 270-5614. 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. /DAVID J LAUX/Primary Examiner, Art Unit 3762 December 16, 2025
Read full office action

Prosecution Timeline

Aug 12, 2022
Application Filed
Dec 08, 2025
Examiner Interview (Telephonic)
Dec 16, 2025
Non-Final Rejection — §102, §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12590760
Spin Rinse Dryer with Improved Drying Characteristics
2y 5m to grant Granted Mar 31, 2026
Patent 12583790
SYSTEM AND METHOD FOR PREPARING SULPHOALUMINATE CEMENT FROM SOLAR ENERGY STORED HEAT DRIED SLUDGE
2y 5m to grant Granted Mar 24, 2026
Patent 12578141
HEATED PAINT DRYING SYSTEM
2y 5m to grant Granted Mar 17, 2026
Patent 12571156
LAUNDRY TREATING APPARATUS AND METHOD FOR CONTROLLING THE SAME
2y 5m to grant Granted Mar 10, 2026
Patent 12571589
DRYING STORAGE
2y 5m to grant Granted Mar 10, 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

1-2
Expected OA Rounds
65%
Grant Probability
93%
With Interview (+28.6%)
3y 1m
Median Time to Grant
Low
PTA Risk
Based on 838 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in for Full Analysis

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

Free tier: 3 strategy analyses per month