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 .
DETAILED ACTION
Claim Rejections - 35 USC § 103
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.
Claim(s) 1 is/are rejected under 35 U.S.C. 103 as being unpatentable over Ozaki (US 20120311992 A1) in view of Marchandise (US 20110062899 A1).
Regarding claim 1
Ozaki discloses a high-power density electric propulsion (EP) system (Hall thruster 10, Fig 3, Para 0109), comprising:
a discharge chamber (an annular discharge space 11, Para 0098 middle) with a longitudinal extension (flow passage 41 of discharge chamber 11 extends longitudinally along dash centerline of thruster 10) according to an axial direction (dash line) of the EP system,
the discharge chamber (11) comprising an annular inner wall (internal annular wall 39) and an annular outer wall (external annular wall 38) made of an electrically conductive material (walls 38 and 39 are made of copper which is electrically conductive, as shown in legend in Fig 3);
an electromagnetic circuit (internal magnetic pole 16, external magnetic pole 17, bottom wall 18, an iron core 19, and a solenoidal coil 21, these components form the magnetic circuit, Para 0100) for generation in the discharge chamber (11) of a magnetic field according to a radial direction (a radial direction magnetic field B, Para 0102 top);
a segmented annular radiator (annular iron bottom wall 18 is one segment and annular iron side wall 20 is another segment, together they are two distinct segments attached to each other, interpreted to be the segmented annular radiator, side wall 20 is provided with cooling parts 22 and 23 for flowing water, Para 0102 bottom, thus side wall 20 acts to radiate heat away from the thruster 10, i.e. radiator) surrounding the discharge chamber (11) and the electromagnetic circuit (iron core 19 of the electromagnet circuit); and
a plurality of first shunts (two annular pieces, one made of Cu and the other made of BN, they are attached together and interpreted to be the plurality of first shunts) radially outwardly projecting from the annular outer wall (the BN shunt projects radially outward from annular outer wall 38) of the discharge chamber (11) to make contact with the segmented annular radiator (the Cu shunt extends outwardly from the BN shunt to make contact with segment 20 of the segmented annular radiator).
PNG
media_image1.png
1030
941
media_image1.png
Greyscale
Ozaki is silent on the first shunts being thermal shunts.
However, Marchandise teaches a Hall thruster (1 Fig 1) having a heat sink made of copper (heat sink 81 is coated at least in part in a coating material, where coating material is selected from copper, Para 0044, 0047).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date to use the segmented annular radiator and the first shunts made of copper in Ozaki, as thermal components being heat sinks, as suggested and taught by Marchandise, in order to dissipate heat produced during power generation of the thruster.
Allowable Subject Matter
Claim(s) 2-27 is/are 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.
i. In claim 2, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the first annular radiator segment is separated from the second annular radiator segment by an axial gap.
In claim 6, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
each thermal shunt of the plurality of first thermal shunts comprises an inner thermal shunt segment connected to an outer thermal shunt segment,
the inner thermal shunt segment is further connected to the annular outer wall of the discharge chamber, and
the outer thermal shunt segment is further connected to the segmented annular radiator.
In claim 7, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the inner thermal shunt segment is electrically conductive, and the outer thermal shunt segment is electrically non-conductive.
In claim 10, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the inner thermal shunt segment is electrically non-conductive, and the outer thermal shunt segment is electrically conductive.
In claim 11, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the inner thermal shunt segment is fastened to the outer thermal shunt segment at a radial position that is distal to the annular outer wall of the discharge chamber and proximal to the segmented annular radiator.
In claim 13, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the inner thermal shunt segment and the annular outer wall of the discharge chamber are monolithically integrated into one structure.
In claim 15, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the inner thermal shunt segment, the annular inner wall of the discharge chamber, and the annular outer wall of the discharge chamber are monolithically integrated into one structure.
In claim 16, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density electric propulsion (EP) system comprising, among other features,
the electromagnetic circuit comprises a magnetic core made of a magnetic material, the magnetic core comprising an inner core structure, an outer core structure, and
an axial extension of the outer core structure comprises a plurality of openings through which the plurality of first thermal shunts project to make contact with the segmented annular radiator.
Claim(s) 28-29 are allowed.
i. In claim 28, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a high-power density magnetically shielded Hall thruster comprising, among other features,
a segmented annular radiator surrounding the outer electromagnetic circuit;
a plurality of first thermal shunts radially outwardly projecting from the discharge chamber to make contact with a first segment of the segmented annular radiator through respective plurality of openings formed in the outer electromagnetic circuit; and
a plurality of second thermal shunts radially inwardly projecting from a second segment of the segmented annular radiator that is separate from the first segment to make contact with the inner electromagnetic circuit.
In claim 29, the cited prior art of record fails to anticipate and/or render obvious, either solely or in combination, a method for operating a magnetically shielded Hall thruster at higher power densities, the method comprising comprising, among other features,
forming a plurality of openings in an outer electromagnetic circuit of the Hall thruster and arranging the outer electromagnetic circuit outwardly the discharge chamber;
arranging a segmented annular radiator outwardly the outer electromagnetic circuit;
radially outwardly projecting a plurality of first thermal shunts from the discharge chamber to make contact with a first segment of the segmented annular radiator through the plurality of openings;
radially inwardly projecting a plurality of second thermal shunts from a second segment of the segmented annular radiator that is separate from the first segment to make contact with the inner electromagnetic circuit; and
based on the increasing efficiency of thermal management, operating the Hall thruster at higher power densities.
Response to Arguments
Applicant’s arguments, see pages 9-10, filed on 10/14/2025, with respect to the rejection(s) of claim(s) 1 under U.S.C. 103 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Ozaki by an alternative interpretation, see details in the rejection above.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Said (US 20210344255 A1) teaches an electric propulsion
Arkhipov (US 5359258 A) teaches a plasma accelerator
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Thuyhang Nguyen whose telephone number is (571)272-5317. The examiner can normally be reached Monday-Friday 8am-5pm EST.
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, Edward F. Landrum can be reached at (571) 272-5567. 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.
/Thuyhang N Nguyen/Examiner, Art Unit 3761
Prosecution Insights