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 .
Response to Amendment
Claims 1-19 remain pending in the application.
The drawing objection is withdrawn in response to the amendment.
The previous claim objection is withdrawn in response to the amendment.
The previous rejections under 35 USC 102 and 103 are withdrawn in response to Applicant’s persuasive arguments. Nakaniwa fails to teach the first row of blades are circumferentially spaced.
Claim Objections
The claims are objected to because of the following informalities:
In claim 10, line 2, “the trailing edge of the second row of blades” should read “the leading edge of the second row of blades”.
In claim 15, “the gap has a length that at least equal” should read “the gap has a length that is at least equal”.
Appropriate correction is required.
Claim Rejections - 35 USC § 102
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 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.
Claims 6-10, 14 and 17-18 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Scheri et al. (US2015/0292333).
PNG
media_image1.png
612
509
media_image1.png
Greyscale
Regarding claim 6, Scheri teaches a method of compressing a fluid, comprising: in a compressor, providing a rotor (1) having a first row of blades (9) spaced circumferentially apart from one another and a second row of blades (10) spaced circumferentially apart from one another, the second row of blades spaced axially apart from the first set of blades to create a gap (D); directing the fluid through the first row of blades; directing the fluid from the first row of blades across the gap; and directing the fluid from the gap through the second row of blades after the gap.
Regarding claim 7, Scheri teaches the first row of blades is at a different circumferential position than the second row of blades.
Regarding claim 8, Scheri teaches the trailing edge of the first row of blades is circumferentially offset from the leading edge of the second row of blades.
Regarding claim 9, Scheri teaches the trailing edge of the first row of blades and the leading edge of the second row of blades are not axially aligned (the blades are considered “not axially aligned” because of a diagonal relationship where a line drawn axially parallel with the rotor shaft from the trailing edge of the first row of blades would not intersect the leading edge of the second row of blades).
Regarding claim 10, Scheri teaches the gap resides between the trailing edge of the first row of blades and the leading edge of the second row of blades.
Regarding claim 14, Scheri teaches a method, comprising: compressing a fluid by, directing a flow of fluid across a first set of inducer type blades (9) spaced circumferentially apart from one another on a rotor in a compressor; and then, directing the flow of fluid across exducer type blades (10) spaced circumferentially apart from one another on the rotor downstream of the set of inducer type blades, wherein the flow of fluid transits a gap (D) after exiting the first set of inducer type blades and before entering the second set of exducer type blades.
Regarding claim 17, Scheri teaches the inducer type blades and the exducer type blades are circumferentially offset from one another.
Regarding claim 18, Scheri teaches the inducer type of blades have a trailing edge that is circumferentially offset from a leading edge of the exducer type of blades.
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 of this title, 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 1-4 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Nakaniwa (US2017/0248154) in view of Amos et al. (US10787963) and Scheri.
Regarding claim 1, Nakaniwa teaches a method for compressing a flow using a compressor, comprising: a first compression step performed by a first impeller (30A) for compressing the flow to a supercritical condition through a first compressor stage so to generate a supercritical flow; a second compression step performed by a second impeller (20A) comprising blades spaced circumferentially apart from one another for compressing the supercritical flow through a second compressor stage; wherein the first compression step is such that, at the end of compression, the fluid is close to critical point (see Fig. 6); wherein between the first compression step and the second compression step there is an isoenthalpic step that maintains substantially constant both total pressure and static pressure (Fig. 6 shows that each section of the compressor has substantially vertical lines on the temperature vs. entropy graph, indicating an isentropic step).
Nakaniwa fails to explicitly teach the flow is CO2.
In an analogous art, Amos teaches a multistage compressor. Amos teaches the working fluid is supercritical CO2 that is a common byproduct of fossil fuel combustion (Col. 1 lines 21-42).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify the method of Nakaniwa and change the supercritical flow to be CO2 as taught by Amos because CO2 is well known in the art as a common byproduct of fossil fuel combustion.
Nakaniwa fails to teach the first impeller comprising blades spaced circumferentially apart from one another.
Cheri teaches a compressor wheel with first and second stages (9, 10) separated by a gap (D). Cheri teaches the first impeller stage has circumferentially spaced blades (see Fig. 2) for providing inflow to the second stage (see paragraph [0018]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify the method of Nakaniwa and change it so that the first impeller comprises blades spaced circumferentially apart from one another as taught by Cheri to provide inflow to the second stage.
Regarding claim 2, Nakaniwa as modified teaches the first compression step is such that, at the end of compression, thermodynamic state point of CO2, on a T-s diagram, is located outside the saturation dome, approximately near CO2 critical point (see Fig. 6, where the saturation dome is represented by line 52, and all compression steps are outside the dome).
Regarding claim 3, Nakaniwa as modified teaches at the end of the first compression step, the pressure is equal or higher than saturation pressure plus a predetermined pressure margin, the pressure margin being related to pressure drop inside the second rotary compressor stage (see paragraph [0014]).
Regarding claim 4, Nakaniwa as modified teaches the first compression step is followed by one or more compressing steps of compressing CO2 flow (see Fig. 4 showing 6 compression sections).
Regarding claim 19, Nakaniwa teaches the method of claim 14, but fails to teach directing the flow of fluid through inlet guide vanes found upstream of the inducer type of blades.
In an analogous art, Amos teaches a multistage compressor utilizing inlet guide vanes (46) to orient the flow direction upstream of an inducer (53).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify the method of Nakaniwa and add a step of directing the flow of fluid through inlet guide vanes found upstream of the inducer type of blades as taught by Amos to orient the flow direction upstream of the inducer.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Nakaniwa in view of Amos, Scheri and Anderson (US2010/0232953).
Regarding claim 5, Nakaniwa as modified teaches the method of claim 1, but fails to teach the first compression step has a pressure ratio smaller than the second compression step.
In an analogous art, Anderson teaches a hybrid axial radial compressor rotor. Anderson teaches it is known in the art that axial compression stages (such as the first compression step in Nakaniwa) have smaller pressure ratios than centrifugal stages (such as the second compression step in Nakaniwa) (see paragraph [0023]).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify the method of Nakaniwa as modified and change it so that the first compression step has a pressure ratio smaller than the second compression step as taught by Anderson because Nakaniwa teaches the first compression step is axial and the second compression step is radial.
Claims 11-13 and 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Scheri in view of Nikpour (US2013/0189094).
Regarding claims 11-12 and 15-16, Scheri teaches the methods of claims 6 and 14, but fails to explicitly teach the gap has a length that is at least equal to a height of a leading edge of the first row of blades, and the gap has a length that is less than two times a height of a leading edge of the first row of blades.
In an analogous art, Nikpour teaches a compressor having first and second stages. Nikpour teaches a gap (generally 45) between the first axial stage (10) and radial stage (11) is at least equal to the leading edge height of the first stage (see Fig. 3). Nikpour teaches the gap accommodates stationary vanes (45) to affect the swirl of flow leading from first to second stage (see paragraph [0080).
It would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify the method of Scheri and change it so that the gap has a length that is at least equal to a height of a leading edge of the first row of blades, and the gap has a length that is less than two times a height of a leading edge of the first row of blades as taught by Nikpour to accommodate stationary vanes to improve flow swirl between the stages.
Regarding claim 13, Scheri teaches the method of claim 6, but fails to teach the rotor has twice as many blades in the second row as the first row.
Nikpour further teaches teaches in order to avoid vibration induced fatigue in the radial compressor (Second stage), it should have a different number of blades compared to the local stator. Similarly, the axial compressor (first stage) should have a different number of blades to that of the stator.
When the general ranges of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. See MPEP 2144.05(II)(A). In the present case, Nikpour teaches the number of blades in the first and second compressor stages are a result effective variable to affect loading of the compressor stage and avoid vibration reduced fatigue. One of ordinary skill in the art could by routine optimization find the optimal number of blades for each stage for the compressor.
It would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify the method of Scheri and change it so that the rotor has twice as many blades in the second row as the first row to optimize a result effective variable to affect loading of the compressor stage and avoid vibration reduced fatigue.
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 CAMERON A CORDAY whose telephone number is (571)272-0383. The examiner can normally be reached M-F 8-4 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, Courtney Heinle can be reached at (571) 270-3508. 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.
/CAMERON A CORDAY/Examiner, Art Unit 3745
/COURTNEY D HEINLE/Supervisory Patent Examiner, Art Unit 3745
Prosecution Insights