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 .
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 (i.e., changing from AIA to pre-AIA ) 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 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.
Claim(s) 12, 16-17, 26-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Tobita US 7,784,267 in view of Renggli US 2006/0016171.
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Regarding claim 12, Regarding claims 12 and 25, Tobita discloses a rotating detonation engine comprising: a radially outer wall, labeled outer wall above, extending along an axis, the dotted line, a radially inner wall, labeled inner wall, extending along the axis, wherein the radially inner wall is positioned within the radially outer wall to define an annular detonation chamber having an inlet, labeled inlet, and an outlet, labeled outlet; the inner wall is within the outer wall and the engine is an annular detonation chamber; see col. 4, lines 17-21; col. 3, lines 53-57. Tobita is not relied upon to disclose wherein the outlet is defined between a static structure and a moveable flow restriction defining a flow area through the outlet, wherein movement of the moveable flow restriction changes the flow area, wherein the static structure comprises a conical section defined on the radially inner wall, and the moveable flow restriction is movable along the axis and along the radially outer wall relative to the conical section. Tobita does teach that the inner wall is a conical structure as shown in the inner wall.
Renggli teaches an exhaust nozzle having a movable section 34 on an outer shroud to define an outlet between a static structure, the exhaust cone 32, and the movable flow restriction 34, 50b defining a flow area through the outlet, wherein movement of the moveable flow restriction changes the flow area, see para. [0027], wherein the static structure comprises a conical section defined on the radially inner wall, and the moveable flow restriction is movable along the axis and along the radially outer wall relative to the conical section. The moveable flow restriction is slidable along the radially outer wall along the axis. Renggli teaches that the exhaust nozzle provides independent control of the throat area and expansion ratio with a simple robust structure. See para. [0007]. Additionally Renggli further teaches the moveable flow restriction is slidable along an inner surface of the radially outer wall section. Element 34 slides along the inner surface 60 of the outer wall.
It would have been obvious to an ordinary skilled worker to provide the exhaust nozzle of Renggli, in the engine of Tobita, in order to provide a means to independently control the throat area and expansion ratio of the engine by a simple robust structure. Id. The Examiner notes that the expansion ratio determines the thrust efficiency of the engine and thus an ordinary skilled worker would understand that the control of the expansion ratio yields control of the efficiency.
Regarding claim 16, Tobita, in view of Renggli, discloses the moveable flow restriction is movably mounted on the inner surface of the radially outer wall. As discussed in claim 12 above, Tobita, in view of Renggli discloses the flow restriction is slidable on the inner surface of the radially outer wall and therefore movably mounted thereto.
Regarding claim 17, Tobita, in view of Renggli, discloses the annular detonation chamber has an annular height H, wherein the annular height increases downstream through the outlet, such that the annular height (H) has a minimum height and increases downstream from the minimum height, the height of the chamber increases from 14 to 15, at least within the section having a centerbody, and wherein the moveable flow restriction extends from the radially outer wall toward the radially inner wall, and has a height that is less than the annular height, the moveable restriction is shown to be less than the height of the chamber as shown in Renggli fig. 2 for example. The annular height has a minimum height where the nozzle outlet is larger than the minimum height and is downstream thereof.
Regarding claim 26, Tobita, in view of Renggli, discloses an actuator 54 functionally connected with the movable flow restriction along axis X.
Regarding claim 27, Tobita, in view of Renggli, discloses a controller communicated with the actuator and operating parameters of the rotating detonation engine and configured to automatically control the position of the movable flow restriction based upon the operating parameters. See Renggli para. [0029] the translation of the shrouds 34, 36 may be controlled by manual inputs to the actuators, the positions for different engine conditions may be scheduled as a function of several engine operating parameters sent to a controller that in turn sends positions commands to the actuators.
Response to Arguments
Applicant's arguments filed 11/07/2025 have been fully considered but they are not persuasive.
The Applicant argues that the prior art Tobita and Renggli are not analogous art because they are not drawn to the same field of endeavor and they are not reasonably pertinent to the problem faced by the inventor. Upon this record, the Examiner disagrees.
In order for a reference to be proper for use in an obviousness rejection under 35 U.S.C. 103, the reference must be analogous art to the claimed invention. In re Bigio, 381 F.3d 1320, 1325, 72 USPQ2d 1209, 1212 (Fed. Cir. 2004). A reference is analogous art to the claimed invention if: (1) the reference is from the same field of endeavor as the claimed invention (even if it addresses a different problem); or (2) the reference is reasonably pertinent to the problem faced by the inventor (even if it is not in the same field of endeavor as the claimed invention). Note that "same field of endeavor" and "reasonably pertinent" are two separate tests for establishing analogous art; it is not necessary for a reference to fulfill both tests in order to qualify as analogous art. See Bigio, 381 F.3d at 1325, 72 USPQ2d at 1212.
The field of endeavor test for analogous art requires the PTO to determine the appropriate field of endeavor by reference to explanations of the invention's subject matter in the patent application, including the embodiments, function, and structure of the claimed invention. See Wood, 599 F.2d at 1036. Here, Tobita is clearly analogous to the claimed invention as both the instant application and Tobita are drawn to rotating detonation wave engines for propulsion. The Applicant however, argues that Renggli is not analogous art since the claimed invention is an RDE which operates on a substantially different combustion process than Renggli which is found to be a deflagration type combustion gas turbine engine. While the Examiner agrees that deflagration combustion and detonation combustion operate on different combustion processes, the relevant structure of Renggli is not related to these differences. Both the claimed invention and the engine of Renglii are air breathing reactionary jet engines, where all three engines, Renglii, Tobita, and the claimed invention, would exhibit similar reactionary thrust at the nozzle. Though Renglii has a turbine 22 aft of the main combustor 18, Renglii also includes an afterburner 28 aft of the turbine and would exhibit pressures and temperatures similar to the engines of Tobita and the claimed invention. Thus, the Examiner finds as a matter of fact that the detonation engine claimed herein and shown by Tobita is in the same field of endeavor as the deflagration combustion engine of Renglii contrary to the Applicant’s assertion. Such a finding of fact is asserted to be supported by substantial evidence on the record. See Koshoffer US 2004/0118104 showing a gas turbine engine similar to Renggli utilizing a deflagration combustor 36 and a pulse detonation engine 12, see para. [0003]; Venkataramani US 2006/0042228 showing a gas turbine engine having a rotating pulse detonation engine having detonation stages 59 with a bladed compressor 42; Dierksmeier US 2014/0260323 teaching a gas turbine engine similar to Renggli where Dierksmeier teaches that the combustor 36 may be a wave rotor combustor, rotary valve combustion system, pulse detonation system, continuous detonation system, sling combustor and may employ deflagration or detonation combustion processes. Thus, contrary to the Applicant’s assertion that the deflagration combustion of Renggli operates differently than the detonation engine of the claimed invention, the prior art appears to support the contention that detonation engines and deflagration engines are in the same field of invention.
The Examiner notes that analogous art test is a two part test where it is incumbent upon the Applicant to show that both prongs are not met. The Examiner asserts that the Applicant has not sufficiently shown that the prior art is not in the same field of endeavor as the claimed invention. Nevertheless, as to the second prong of the test, the Examiner also asserts that the prior art seeks to solve the same or similar problem as the claimed invention. The Applicant’s disclosure states that the actuator 90 is desirable to control the position and flow restriction based on operating parameters to provide the desired wide envelope of operability while maintaining stable rotating detonation. See para. [0050]. Likewise Renggli teaches that a need for an exhaust nozzle to independently control the throat area, i.e. restriction, and expansion ratio using a simple, robust structure. Renggli teaches variable geometry nozzles are required to operate exhaust systems over a wide range of pressure ratios and to adjust the nozzle expansion ratios in order to attain good performance at various operating points. See para. [0002]. Thus, Renggli’s nozzle seeks to alter the restriction of the flow to provide a wider operability envelope. Thus, the Examiner does not agree that the prior art does not seek to solve the same problem.
The Applicant states that Renggli is strikingly different than the claimed invention because: 1) Renggli describes a split shroud while the disclosed invention is drawn to a single sided translating nozzle; 2) Renggli is not specific as to the type of flow, that is supersonic or subsonic; 3) Renggli describes there invention as for a gas turbine; 4) Renggli describes their nozzle is to kinematically optimize nozzle geometry for a wide range of nozzle pressure ratios versus the need to back pressure an RDE for sustained detonation of the claimed invention.
As to the first and fourth issues, though Renggli teaches a split shroud and the Applicant’s is a singled sided translating nozzle, both the invention and Renggli are at least in part directed to providing adjustments to the flow to operate over a wide range of operating conditions. The Examiner notes that the Applicant states that the variable nozzle of the invention is drawn to back pressuring an RDE but the full text of the solution is to provide a desired wide envelope of operability while maintaining stable rotating detonation. See para. [0050] of US 2024/0077028. Thus, both inventions are at least in part drawn to the adjustment of flow to optimize thrust over a wide range of operating conditions.
The Examiner disagrees with the contention that Renggli is silent to the type of flow, subsonic or supersonic. Renggli states that the engine operates in high speed cruise conditions, see para. [0032] and takeoff low noise subsonic cruise conditions, see para. [0033]. Typical supersonic engines operate with afterburners. See para. [0003]. Additionally, the subsonic configurations in figs. 3 and 5 show a converging nozzle whereas the high speed configurations in figs. 2 and 4 show a CD nozzle consistent with supersonic flow. Thus, on the preponderance of the evidence, Renggli does disclose the conditions of the exhaust flow.
As to the third point, as addressed above, the prior art acknowledges the use of detonation combustion with gas turbine engines. Thus, the mere fact that Renggli is a gas turbine is insufficient to shift the burden that the references are not analogous.
The Examiner notes that the Applicant is correct that the nozzle of the disclosed invention differs from the nozzle of the prior art; however, such differences are not claimed and the Applicant may amend the claims to capture such distinction. Absent such amendments, the Examiner disagrees with the arguments and the rejection is maintained.
Conclusion
THIS ACTION IS MADE FINAL. 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 GERALD LUTHER SUNG whose telephone number is (571)270-3765. The examiner can normally be reached 9-5 PST.
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/GERALD L SUNG/Primary Examiner, Art Unit 3741