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 .
This is in response to the correspondence filed on 10/10/2025.
Drawings
The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the “a gravity center of the double-ball bearing is axially positioned between a first plane that intersects a forwardmost point of a leading edge of the unducted fan and a second plane that intersects a downwardmost point of a trailing edge of the unducted fan” (inter alia, claim 2) must be shown or the feature(s) canceled from the claim(s). No new matter should be entered. It is noted that Fig. 2a appears to show double-ball bearings within P1 and P2, but they are associated with ducted fan 40.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 2, 4, 5, 7, 9, 11, and dependent claims, are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 2: in “the double-ball bearing is positioned radially inwardly of the ducted fan”, it is unclear how a position “radially inwardly” is defined, it is not clear what a radial direction is, in relation to what references.
Claim 4: in “a downwardmost point of a trailing edge of the unducted fan” it is unclear what downwardmost refers to. It is unclear how up and down are defined, and how downward and downwardmost are defined, and in relation to what point(s) or components, etc.
Claim 5 recites the limitation “gravity center. It is unclear if the claim refers to the gravity center of the forward ball bearing and the forward ball bearing as a whole, or to the same gravity center, or something else.
Claim 7; in “the double-ball bearing is downward of the ducted fan” it is unclear what downward refers to. It is unclear how up and down are defined, and in reference to what point(s).
Claim 9: recites the limitation “gravity centerIt is unclear if the claim refers to the gravity center of the forward ball bearing and the forward ball bearing as a whole, or to the same gravity center, or something else.
Claim 11: recites the limitation “only comprise” in “the bearings only comprise the double-ball bearing between a first plane that intersects a forwardmost point of a leading edge of the unducted fan and a fourth plane that intersects a downwardmost point of a trailing edge of a downwardmost rotor blade of the low-pressure compressor”, but it is unclear what “only comprises” is intended to mean. It is unclear how up and down are defined, and how downward and downwardmost are defined, and in relation to what point(s) or components, etc.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1-9, 11-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Mondal 20230417152 in view of Silvester 20250163854.
Regarding claim 1, Mondal teaches:
An open rotor propulsion system (inter alia, Figs. 5, 13, both show unducted gas turbine engines that are the same, or appear to be the same, but show the drawings highlight different components) comprising:
a fan section including an unducted rotating element (550, Fig. 5)(554, Fig. 5) and a non-rotating stationary element (562);
a forward frame (570) housing an inlet duct (580) including an inlet (582) located between the unducted rotating element and the non-rotating stationary element (Fig. 5)
a ducted fan (mid-fan 586 [0135], Fig. 5) positioned aft the unducted rotating element (Fig. 5) within the inlet duct (Fig. 5), wherein the ducted fan comprises a second array of fan airfoil blades (588);
a fan duct (572) and a core duct (542) extending aft the ducted fan (Fig. 5);
an engine (520) positioned within the core duct (Fig. 5) and comprising a low-pressure compressor (526), a high-pressure compressor (528), an intermediate case (Image below) located between the low- pressure compressor and the high-pressure compressor (Fig. 5, Image below), a fan drive turbine (534) and a shaft (538) connected to the fan drive turbine and configured to drive the ducted fan (Fig. 5); and
bearings (inter alia, “The low-pressure shaft 1322 is supported by two bearings on the forward side of the core (e.g., a first bearing 1323a and a six bearing 1315 forward of the first bearing 1323a) and two bearings on the aft side of the core (e.g., the fourth bearing 1323b and the fifth bearing 1329)” [0213-0214]) configured to support the shaft (1322) with respect to an engine case (Figs. 13, 5, “The low-pressure shaft 1322 is rotationally supported in the gas turbine engine 1300 with one or more bearings” [0214]), wherein the bearings comprise a double-ball bearing connected to one of the forward frame and the intermediate case (see 1315 and 1323a, Fig. 13).
Mondal teaches the use of “pair of ball bearings” [0173-0175], teaching “bearing comprise double-ball bearings”, “[0168] Bearings may be ball-type bearings […] Different types of bearings may be mixed in various bearing layouts. According to additional embodiments, different bearing layouts were considered […] in order to determine which combination would work best for a given architecture and need, as well as taking into account competing engineering requirements. […] It was found that these variations can improve the critical speed and/or be more suitable to accommodate space limitations, lubrication resources or other architecture-imposed limitations [0168-0170].” And Mondal also teaches: “Duplex bearing arrangements may also be referred to as double-row bearings, or overturning moment (OTM) bearings, since they provide moment stiffness to the shaft, i.e., provide resistance to rotation across the bearing locations [0173].” But Mondal does not explicitly state the double ball bearings at the locations as claimed.
However, Silvester teaches “The front engine structure 42 is substantially conical in shape in the arrangement shown in FIGS. 1 and 14, extending rearwardly and outwardly from the forward bearing, a, towards the engine section stator 24. It is rigidly mounted on the engine stationary structure 24” [0155], and:
double-ball bearing (bearings a and c, see Fig. 14)
bearings (Fig. 14, a and c) configured to support the shaft (fan shaft 36 [0151]) with respect to an engine case (inter alia, via 24), wherein the bearings comprise a double-ball bearing (Silvester teaches double bearings, Fig. 14, Mondal teaches double-ball bearings as discussed above) connected to one of the forward frame (inter alia, via 24)
It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Mondal with Silvester's teachings discussed above in order to provide an extra set of bearings to add safety to the system, as taught by Silvester [0153].
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Regarding claim 2, Mondal in view of Silvester teaches the invention as discussed for claim 1. Mondal further teaches:
The open rotor propulsion system of claim 1, wherein the double-ball bearing (1315, Fig. 13; double-ball bearing as already discussed) is positioned radially inwardly of the ducted fan (Image below).
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Regarding claim 3, Mondal in view of Silvester teaches the invention as discussed for claim 2. Mondal further teaches:
The open rotor propulsion system of claim 2, wherein the double-ball (as already discussed) bearing is connected to the forward frame (In some embodiments the first bearing 1323a and the second bearing 1324 may be located so as to provide direct support for both a center frame (supporting the core) and a forward frame (supporting, e.g., the booster)) [0217]
Regarding claim 4, Mondal in view of Silvester teaches the invention as discussed for claim 2. Mondal further teaches:
wherein a gravity center (image below, center of gravity found between the bearings) of the double-ball bearing (double-ball bearing as already discussed) is axially positioned between a first plane (P1, image below) that intersects a forwardmost point of a leading edge (image below) of the unducted fan (see P1) and a second plane (P2, Image below) that intersects a downward most point of a trailing edge (image below) of the unducted fan (23).
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Regarding claim 5, Mondal in view of Silvester teaches the invention as discussed for claim 4.
Mondal in view of Silvester, as discussed so far, teaches the double ball bearings as already discussed, but is silent about:
wherein the double-ball bearing
Silvester teaches:
The open rotor propulsion system(double ball bearing as already discussed) (location of “a”, Fig. 14) and a downward ball bearing (location of “c”, Fig. 14), gravity centers of the forward ball bearing and the forward ball bearing (gravity center of the forward ball bearing and the same forward ball bearing, is the gravity center of the forward ball bearing; image below) being both axially positioned between the first plan (gravity center is between the planes, see image below).
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Regarding claim 6, Mondal in view of Silvester teaches the invention as discussed for claim 1.
Mondal further teaches:
wherein the double-ball bearing (double ball bearing already discussed) is connected to the intermediate cas(Image below).
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Regarding claim 7, Mondal in view of Silvester teaches the invention as discussed for claim 6. Mondal teaches:
The open rotor propulsion system of claim 6, wherein the double-ball bearing (as already discussed) is downward of the ducted fan (see location of 1323a in Fig. 13, location of 1323a, where the double ball bearing is located is downward of 1321 on the page of Fig. 13, and it is also aft of 1321).
Regarding claim 8, Mondal in view of Silvester teaches the invention as discussed for claim 6.
Mondal further teaches:
The open rotor propulsion system of claim 6, wherein a gravity center of the double-ball bearing (indicated in the image below, found between “first pair of ball bearings 925a, 926a” [0174], Fig. 9c) is axially positioned between a third plane that intersects a forwardmost point of a leading edge of a forwardmost rotor blade (P3, Image below, where 921 represents the booster, implying the existence of rotor blade with leading edge and trailing edge that would be located within the area marked by 921 in fig. 9c. It is further noted that Figs. 9A-9E show various bearing configurations with respect to the booster 921, emphasizing the point that 9C shows a specific design where the ball bearings are found at a central location, substantially axially aligned with the center of the compressor section) of the low-pressure compressor (921) and a fourth plane that intersects a downward most point of a trailing edge of a downwardmost rotor blade (P4, Image below) of the low-pressure compressor (921).
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Regarding claim 9, Mondal in view of Silvester teaches the invention as discussed for claim 8.
Mondal further teaches:
The open rotor propulsion system of claim 8, wherein the double-ball bearing comprises a forward ball bearing and a downward ball bearing (indicated in the image below, found between “first pair of ball bearings 925a, 926a” [0174], Fig. 9c), gravity centers of the forward ball bearing and the forward ball bearing (gravity center of the forward ball bearing and the same forward ball bearing, is the gravity center of the forward ball bearing; image below) being both axially positioned between the third plane and the fourth plane (image below).
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Regarding claim 11, Mondal in view of Silvester teaches the invention as discussed for claim 1.
Mondal further teaches:
The open rotor propulsion system of claim 1, wherein the bearings only comprise the double-ball bearing (double-ball bearing as already discussed; location in image below) between a first plane (P1, image below) that intersects a forwardmost point of a leading edge of the unducted fan (P1 intersects the forwardmost point of a leading edge of the blade shown Fig. 13) and a fourth plane (P4, Image below) that intersects a downwardmost point of a trailing edge of a downwardmost rotor blade (Image below) of the low-pressure compressor (booster 1321).
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Regarding claim 12, Mondal in view of Silvester teaches the invention as discussed for claim 1.
Mondal further teaches:
An aircraft (“an aircraft” [0126]) comprising at least one open rotor propulsion system (an unducted, three-stream, gas turbine engine 510 for an aircraft [0126]) according to claim 1,
Mondal in view of Silvester, as discussed so far, is silent about:
wherein the open rotor propulsion system is connected to the aircraft via a pylon
However, Silvester teaches:
wherein the open rotor propulsion system is connected to the aircraft via a pylon (The engine 10 is arranged to be mounted on a wing of an aircraft for use, by means of one or more mounts 41 [0147], where the mount reads on pylons).
Claim(s) 10, 13, is/are rejected under 35 U.S.C. 103 as being unpatentable over Mondal 20230417152 in view of Silvester 20250163854 and Richards 20060201160.
Regarding claim 10, Mondal in view of Silvester teaches the invention as discussed for claim 1.
Mondal in view of Silvester is silent about:
The open rotor propulsion system of claim 1, wherein the double-ball bearing comprises two ball bearings axially offset by at most 300 mm.
However, Richards teaches “shaft 200 is associated with a low pressure turbine 204” [0022] and Richards teaches: “the shaft 200 can be tuned to acceptable frequency characteristics. Such tuning is achieved by essentially creating an encastered support at the end of the shaft 200. This encastered support is created by use of the cradle 221. In such circumstances the shaft 200 is as indicated encastered rather than simply supported such that there is a raising in the normal shaft frequency. Fine tuning of the fundamental frequencies is achieved by varying the distance between the two bearings 222, 223 in the cradle 221 in addition to alterations in the stiffness of the support cradle 221 and the resilient spring in the bearing races for the bearings 222, 223” [0022]
It is therefore desirable to reduce fine tune the fundamental frequencies between the two bearings, as taught by Richards. It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Mondal in view of Silvester with Richard’s teachings discussed above in order to fine tune fundamental frequencies to acceptable frequency characteristics, as taught by Richards and discussed above.
The distance between the bearings was thus recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case tuning shaft frequencies such that fundamentally detrimental shaft frequencies can be configured to occur at rotational speed ranges which are less harmful” inlet length to diameter (Richards, [0027]), such that the determination of the optimum or workable ranges of said variable, in this case the distance between bearings, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Mondal in view of Silvester the inlet length, it has been held that the discovery of optimum or workable ranges, in this case two ball bearings axially offset by at most 100 mm, by experimentation requiring only routine skill in the art, in this case the ability to adjust the distance between bearings, as taught by Richards, would have been an extension of prior art teachings to tune the shaft frequencies as desirable. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A); In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980); MPEP 2144.05(II)(B).
Regarding claim 13, Mondal in view of Silvester teaches the invention as discussed for claim 1.
Mondal in view of Silvester is silent about:
wherein the double-ball bearing comprises two ball bearings axially offset by at most 100 mm.
However, Richards teaches “shaft 200 is associated with a low pressure turbine 204” [0022] and “the shaft 200 can be tuned to acceptable frequency characteristics. Such tuning is achieved by essentially creating an encastered support at the end of the shaft 200. This encastered support is created by use of the cradle 221. In such circumstances the shaft 200 is as indicated encastered rather than simply supported such that there is a raising in the normal shaft frequency. Fine tuning of the fundamental frequencies is achieved by varying the distance between the two bearings 222, 223 in the cradle 221 in addition to alterations in the stiffness of the support cradle 221 and the resilient spring in the bearing races for the bearings 222, 223” [0022].
It is therefore desirable to reduce fine tune the fundamental frequencies between the two bearings, as taught by Richards. It would have been obvious to a person having ordinary skills in the art before the effective filing date of the claimed invention to provide Mondal in view of Silvester with Richard’s teachings discussed above in order to fine tune fundamental frequencies to acceptable frequency characteristics, as taught by Richards and discussed above.
The distance between the bearings was thus recognized as a result-effective variable, i.e., a variable which achieves a recognized result, in the prior art, in this case tuning shaft frequencies such that fundamentally detrimental shaft frequencies can be configured to occur at rotational speed ranges which are less harmful” inlet length to diameter (Richards, [0027]), such that the determination of the optimum or workable ranges of said variable, in this case the distance between bearings, may have been characterized as routine experimentation. In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977); MPEP 2144.05(II)(B). Where the general conditions of a claim are disclosed in the prior art, in this case Mondal in view of Silvester the inlet length, it has been held that the discovery of optimum or workable ranges, in this case two ball bearings axially offset by at most 100 mm, by experimentation requiring only routine skill in the art, in this case the ability to adjust the distance between bearings, as taught by Richards, would have been an extension of prior art teachings to tune the shaft frequencies as desirable. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP 2144.05(II)(A); In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980); MPEP 2144.05(II)(B).
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Roberto T. Igue whose telephone number is (303)297-4389. The examiner can normally be reached Monday-Friday 7:30-4:30 PT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Phutthiwat Wongwian can be reached at (571) 270-5426. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ROBERTO TOSHIHARU IGUE/Examiner, Art Unit 3741
/PHUTTHIWAT WONGWIAN/Supervisory Patent Examiner, Art Unit 3741
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