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 .
This is responsive to the amendment filed on September 10, 2025. Claims 1-11, 13, 26-27, 29-32, and 34-41 are pending with claims 3-6 and 26 being previously withdrawn. The objection to claim 1 is withdrawn due to the amendment. The indefiniteness rejection is maintained as claims 1 and 10-11 still recite indefiniteness language.
Response to Arguments
Applicant's arguments filed September 10, 2025 have been fully considered but they are not persuasive. Applicant argues the KSR based obvious to try rejection of claim 39 is faulty because it fails to articulate a motivation (page 8). As set forth in MPEP 2144, obviousness can be supported by legal precedent. KSR establishes rationales to support obviousness including obvious to try (see MPEP 2143 (E)). The rationale to support a conclusion that the claim would have been obvious is that "a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely that product [was] not of innovation but of ordinary skill and common sense. In that instance the fact that a combination was obvious to try might show that it was obvious under § 103." KSR, 550 U.S. at 421, 82 USPQ2d at 1397. If any of these findings (see MPEP 2143(E)) cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.
Applicant’s arguments, see page 7, filed September 10, 2025, with respect to the combination of Myer and Mukherjee failing to disclose “the fixed ring and rotatable ring arranged concentrically” 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 Therefore, the rejection has been withdrawn.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 further view of Madison (US 2012/0248786).
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 10-11 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 10 recites “the stator vanes are slidably coupled via a slot and a pin retained within the slot”. There is not support for multiple vanes being coupled a single slot and a pin. Note that each stator vane has a slot 212 (see elected species of Fig. 2B) and there is not support for a single slot for slidably coupling the stator vanes. The lack of support for this limitation consequently raise doubt as to possession of the claimed invention at the time of filing.
Claim 11 fails to comply with written description requirement based on its dependence on claim 10.
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 1-2, 7-11, 13, 27, and 29-41 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 1 recites the limitation "the vane" in line 17. There is insufficient antecedent basis for this limitation in the claim.
Claim 10 recites “the stator vanes are slidably coupled via a slot and a pin retained within the slot”. It is unclear whether the claims are directed to a single slot or multiple discrete slots for each vane.
Claims 2, 7-11, 13, 27, and 29-41 are indefinite based on their dependence on the above claims.
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, 8-11, 13, 27, 29-32, 34 and 41 is/are rejected under 35 U.S.C. 103 as being unpatentable over Myers (US 2008/0252077) in view of Madison (US 2012/0248786) and Mukherjee (US 2007/0071595).
Regarding claim 1, Myers discloses a turbo expander (100, par. 18) comprising:
a hermetically sealed housing (par. 39) defining an inlet (105) and an outlet (109);
an impeller (120) configured to be rotated by a flowing fluid flowing from the inlet to the outlet;
a fluid stator (118, par. 26) between the inlet and the impeller, positioned at the periphery of the impeller and encircling the impeller (par. 26, Figs. 2-3);
an actuator (par. 26);
an electric rotor (150) between the fluid stator and the outlet, the electric rotor coupled to the impeller (Fig. 2) and configured to rotate in unison with the impeller;
an electric stator (162) encircling the electric rotor, the electric stator comprising coil windings (see “coils”, par. 22); and
the hermetically sealed housing encompassing the fixed ring, the rotatable ring, the plurality of stator vanes, the electric rotor, and the electric stator (par. 39, Fig. 2).
Myer does not disclose the fluid stator comprising:
a fixed ring parallel to a plane of rotation of the impeller, the fixed ring having a center in-line with a center of rotation of the impeller;
a rotatable ring rotatable relative to, and parallel to, the fixed ring, the rotatable ring having a center in-line with a center of rotation of the impeller, the fixed ring and rotatable ring arranged concentrically; and
a plurality of stator vanes extending between the fixed ring and the rotatable ring, the plurality of stator vanes defining an inlet cross sectional area upstream of the impeller, the cross sectional area being dependent upon a relative position of the fixed ring and the rotatable ring, the plurality of stator vanes comprising a perimeter sidewall surface defined by a curved leading surface spanning from a planar sidewall surface to a curved sidewall surface on an opposing side of the vane from the planar sidewall surface, the curved leading surface defining a leading surface at one end of the vane and the curved sidewall surface and planar sidewall surface converging to a trailing surface at an opposing end of the vane, the curved sidewall surface curving from the curved leading surface to the trailing surface, and where the curved sidewall surface of one of the plurality of vanes is adjacent to the planar sidewall surface of an adjacent vane when the vanes are in a fully closed configuration; and
the actuator configured to rotate the rotatable ring.
Madison disclose the fluid stator (Figs. 2-6) comprising:
a fixed ring (201 including non-movable base 211) parallel to a plane of rotation of the impeller, the fixed ring having a center in-line with a center of rotation of the impeller (Fig. 3A);
a rotatable ring (209) rotatable relative to, and parallel to, the fixed ring, the rotatable ring having a center in-line with a center of rotation of the impeller, the fixed ring and rotatable ring arranged concentrically (Figs. 2, 3A); and
a plurality of stator vanes (203) extending between the fixed ring (201) and the rotatable ring (209), the plurality of stator vanes defining an inlet cross sectional area upstream of the impeller, the cross sectional area being dependent upon a relative position of the fixed ring and the rotatable ring.
Myer discloses a turbo expander with a fluid stator (see inlet nozzle device with adjustable inlet nozzle geometry, par. 26), however does not disclose the particular claimed arrangement. Madison, which is also directed to a turbo expander, discloses a fluid stator with the claimed arrangement which enables changes to flow rates and differential pressures without shutting the turboexpander down (Madison par. 9). Thus, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the turbo expander of Myer by providing the fluid stator comprising: a fixed ring parallel to a plane of rotation of the impeller, the fixed ring having a center in-line with a center of rotation of the impeller the fixed ring and rotatable ring arranged concentrically; a rotatable ring rotatable relative to, and parallel to, the fixed ring, the rotatable ring having a center in-line with a center of rotation of the impeller; and a plurality of stator vanes extending between the fixed ring and the rotatable ring, the plurality of stator vanes defining an inlet cross sectional area upstream of the impeller, the cross sectional area being dependent upon a relative position of the fixed ring and the rotatable ring, as taught by Madison, to change to flow rates and differential pressures without shutting the turboexpander down (Madison par. 9).
Furthermore, Mukherjee discloses a plurality of stator vanes (7) comprising a perimeter sidewall surface defined by a curved leading surface (unlabeled, adjacent to 13 in Fig. 3) spanning from a planar sidewall surface (unlabeled on radially inner side of 7 in Fig. 3) to a curved sidewall surface (unlabeled on radially outer side of 7 in Fig. 3) on an opposing side of the vane from the planar sidewall surface, the curved leading surface defining a leading surface at one end of the vane and the curved sidewall surface and planar sidewall surface converging to a trailing surface at an opposing end of the vane (Fig. 3), the curved sidewall surface curving from the curved leading surface to the trailing surface (Fig. 3), and where the curved sidewall surface of one of the plurality of vanes is adjacent to the planar sidewall surface of an adjacent vane when the vanes are in a fully closed configuration (top of Fig. 3) and an actuator (16) configured to rotate a rotatable ring.
Myer discloses a turbo expander with a fluid stator (see inlet nozzle device with adjustable inlet nozzle geometry, Myer par. 26), however does not disclose the particular stator vanes shape and actuator arrangement. Mukherjee, which is analogous art, discloses a fluid stator which adjusts the vane position in the stator (Mukherjee par. 27) controlling the flow into the turbine in the various positions (Fig. 3). Thus, it would have been obvious to one having ordinary skill in the art before the effective filing date to modify the turbo expander of Myer by providing the fluid stator comprising the stator vanes comprising a perimeter sidewall surface defined by curved leading surface spanning from a planar sidewall surface to a curved sidewall surface on an opposing side of the vane from the planar sidewall surface, the curved leading surface defining a leading surface at one end of the vane and the curved sidewall surface and planar sidewall surface converging to a trailing surface at an opposing end of the vane, the curved sidewall surface curving from the curved leading surface to the trailing surface, and where the curved sidewall surface of one vane is adjacent to the planar sidewall surface of the adjacent vane when the vanes are in a fully closed configuration; and the actuator configured to rotate the rotatable ring, as taught by Mukherjee, to utilize a known vane shape and actuator arrangement that controls flow into the turbine.
Regarding claim 8, the modified turbo expander of Myers comprises each and every of the plurality of stator vanes is rotatably fixed (via pin Madison 322) to the fixed ring (Madison Fig. 3B).
Regarding claim 9, the modified turbo expander of Myers comprises each and every of the plurality of stator vanes are rotatable and slidably coupled to the rotatable ring (Madison 209, via pin Madison 324 and slot Madison 206, Madison Fig. 3B).
Regarding claim 10, the modified turbo expander of Myers comprises being slidably coupled comprises slot (Madison 206) and a pin (Madison 324) retained within the slot (Madison Fig. 3B).
Regarding claim 11, the modified turbo expander of Myers comprises the slot is defined by the each of the plurality of stator vanes (Madison Fig. 3B).
Regarding claim 13, the modified turbo expander of Myers comprises an active magnetic bearing (Myers 115, 145) supporting the impeller or the electric rotor (Myers par. 20).
Regarding claim 27, the modified turbo expander of Myers comprises the electric rotor is a permanent magnet rotor (Myers par. 22).
Regarding claim 29, the modified turbo expander of Myers comprises the electric rotor (Myers 150) and the electric stator (Myers 162) define an annulus therebetween (Myers Fig. 1), and where the turbo expander is configured to flow at least a portion of the fluid flowing from the inlet to the outlet through the annulus (Myers par. 23, see “the working fluid is directed to flow …between the stator 162 and rotor 140”).
Regarding claim 30, the modified turbo expander of Myers comprises the electric stator (Myers 162) and the hermetically sealed housing (Myers 107) define a second annulus therebetween (Myers Fig. 1), and where the turbo expander is configured flow at least a portion of the fluid flowing from the inlet to the outlet through the second annulus (Myers par. 23).
Regarding claim 31, the modified turbo expander of Myers comprises the electric stator and electric rotor are exposed to the fluid flowing from the inlet to the outlet (Myers Fig. 1, par. 23).
Regarding claim 32, the modified turbo expander of Myers comprises the fluid stator (Myers 118, Fig. 3) resides immediately adjacent the impeller (Myers 120, Fig. 3; also see Madison Fig. 2).
Regarding claim 34, the modified turbo expander of Myers comprises the electric rotor and the electric stator are downstream of the impeller in the fluid flowing from the inlet to the outlet (Myers Fig. 3).
Regarding claim 41, the modified turbo expander of Myers comprises the plurality of stator vanes reside entirely within the outer diameter of the rotatable ring (Mukherjee Fig. 3, Madison Figs. 6-7).
Claims 2 and 40 is/are rejected under 35 U.S.C. 103 as being unpatentable over Myers (US 2008/0252077) in view of Madison (US 2012/0248786) and Mukherjee (US 2007/0071595), and in further view of DiBenedetto (US 2019/0101061).
The modified turbo expander of Myers contains all of the claimed elements as set forth in the rejection of claim 1, except a gear train that comprises a rack and a pinion, wherein the rotatable ring comprises gear teeth to define the pinion, the actuator being coupled to the rack and configured to move the rack, and where the actuator comprises a linear actuator coupled to the rack and configured to linearly move the rack.
DiBenedetto discloses a gear train that comprises a rack and a pinion (232, 234, Figs. 5-6), wherein a rotatable ring (214) comprises gear teeth (234) to define the pinion, an actuator (230) being coupled to the rack and configured to move the rack (Figs. 5-6, par. 47) and where the actuator (230) comprises a linear actuator coupled to the rack and configured to linearly move the rack (Figs. 5-6, par. 47).
Myers, as modified by Mukherjee, contains an actuator to move the rotatable ring, however lacks a rack and pinion configuration. DiBenedetto, which is also directed to a control system for a turbine, discloses a rack and pinion configuration with a rotatable ring which induces rotation of the sleeve about the axis (par. 47). Thus, it would have been obvious to one having ordinary skill in the art before the effective filing of the claimed invention to further modify the turbo expander of Myers by providing a gear train that comprises a rack and a pinion, wherein the rotatable ring comprises gear teeth to define the pinion, the actuator being coupled to the rack and configured to move the rack, and where the actuator comprises a linear actuator coupled to the rack and configured to linearly move the rack, as taught by DiBenedetto, to utilize a known actuator assembly that induces rotation of a rotatable member about the axis (DiBenedetto par. 47).
Claims 7, 35 and 39 is/are rejected under 35 U.S.C. 103 as being unpatentable over Myers (US 2008/0252077) in view of Madison (US 2012/0248786) and Mukherjee (US 2007/0071595), and in further view of King (US 2016/0230586).
Regarding claims 7 and 35, the modified turbo expander of Myers contains all of the claimed elements as set forth in the rejection of claim 1, except the actuator is a linear actuator or a rotary motor.
King discloses an actuator for adjusting the position of a rotatable ring is a linear actuator (par. 50) or a rotary motor (par. 49).
Myers discloses a turbo expander with an actuator for the variable fluid stator, however does not disclose a linear actuator or a rotary motor. King, which is also directed to a control system for a radial turbine, discloses an actuator is a linear actuator or a rotary motor which enables adjustment of the vanes based on a control unit with precision and reduced hysteresis (par. 8). Thus, it would have been obvious to one having ordinary skill in the art before the effective filing of the claimed invention to further modify the turbo expander of Myers by providing a linear actuator or a rotary motor, as taught by King, to drive the rotary ring based on a control unit with precision and reduced hysteresis (par. 8).
Regarding claim 39, the modified turbo expander of Myers comprises a second actuator (Myers par. 26 “one or more actuators’) coupled to the rotatable ring and configured to rotate the rotatable ring (Mukherjee Figs. 1-3).
The modified turbo expander of Myers lacks the first actuator is coupled to the rotatable ring differently than the second actuator.
Although, none of the prior art references disclose different actuator types together such that the first actuator is coupled to the rotatable ring differently than the second actuator, it would have been obvious to try. See MPEP 2143(E). The MPEP states there must be findings of: (1) a recognized problem or need in the art; (2) a finite number of identified, predictable solutions to the recognized need to problem; and (3) one of ordinary skill in the art could have pursued the known potential solution with a reasonable expectation of success. In this case, there is a recognized problem of needing to transfer actuator movement into a rotary movement to drive a rotating ring. Specifically, Mukherjee discloses a crank mechanism engaging a slot for adjusting the pivotal position of the vanes (Mukherjee par. 27), and King further disclose rotary actuators at various gear ratios and, alternatively, linear actuators with linkages which engage gearing on the rotating ring (King pars. 49-50). There are a finite number of different types of mechanical couplings (cam/slots, teeth and/or linkages) which convert the energy from the actuator to drive the rotation ring. A person having ordinary skill in the art could have pursued the known potential solution with reasonable expectation of success and predictability to determine the types of actuators and corresponding couplings to appropriately drive the rotating ring. There would have been a reasonable expectation of success since the different types of couplings function in similar manner to transmit motion into rotary motion of the rotation ring. Accordingly, it would have obvious to try different couplings for actuators to pursue the known options within their technical grasp.
Claim(s) 36-38 is/are rejected under 35 U.S.C. 103 as being unpatentable over Myers (US 2008/0252077) in view of Madison (US 2012/0248786) and Mukherjee (US 2007/0071595) as applied to claim 1 above, and further in view of Mitsubori (US 5,028,208).
Regarding claim 36, the modified turbo expander of Myers contains all of the claimed elements as set forth in the rejection of claim 1 above, except the rotatable ring comprises a tab extending outwardly form an outer circumferential surface of the ring, wherein the actuator is coupled to the tab to rotate the rotatable ring.
Mitsubori discloses a rotatable ring (segmented ring 37) comprises a tab (42) extending outwardly form an outer circumferential surface of the ring (defined on 38’ in Fig. 4), wherein an actuator (43) is coupled to the tab to rotate the rotatable ring (Fig. 4).
Myer discloses a turbo expander with a fluid stator with an actuator, however does not disclose the rotatable ring with a tab. Mitsubori, which is analogous art, discloses a tab which forms a drive lever connecting at its outer end to the actuator to enhance torque transmission. Thus, it would have been obvious to one having ordinary skill in the art before the effective filing of the claimed invention to further modify the turbo expander of Myer by providing the rotatable ring comprises a tab extending outwardly form an outer circumferential surface of the ring, wherein the actuator is coupled to the tab to rotate the rotatable ring, as taught by Mitsubori, to form a drive lever which enhances torque transmission to the drive assembly.
Regarding claim 37, the modified turbo expander of Myers comprises the actuator is coupled to the tab without a linkage (Mitsubori Fig. 4).
Regarding claim 38, the modified turbo expander of Myers comprises the actuator is a linear actuator (Mitsubori 43, Mitsubori Fig. 4).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 JESSE M PRAGER whose telephone number is (571)270-1412. The examiner can normally be reached M-F 9-5 EST.
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/JESSE M PRAGER/Examiner, Art Unit 3745
10/6/2025
/COURTNEY D HEINLE/Supervisory Patent Examiner, Art Unit 3745