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
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 and 9-17 is/are rejected under 35 U.S.C 103 as being unpatentable over CUNNINGHAM(US20110052432A1) in view of DANNER(US6309188B1).
Regarding claim 1, Cunningham teaches a magnetic thrust bearing(Figs. 2-5) comprising: a rotor assembly(319/307) configured to rotate, wherein the rotor assembly comprises a thrust disk(rotating axial load-receiving element surface with magnetic bearing 318 equivalent to thrust disk) having a first side and a second side, a stator assembly(323), wherein the stator assembly comprises a magnet assembly(318, 319) acting on the thrust disk, wherein the magnetic thrust bearing(318) is configured to be cooled by a fluid(Cooling fluid circulation via impeller 504)(Para[0048-0071]),
wherein at least the first side of the thrust disk is configured to receive the fluid(Para[0069], cooling fluid introduced into rotor cavity 330 adjacent axial magnetic bearing 318) and an outer periphery of the thrust disk is configured to discharge the fluid(Para[0071-0073], fluid exits rotor/stator cavity via circulations paths and exhaust regions).
Cunningham is silent wherein the thrust disk comprises a plurality of blades at said outer periphery, wherein the plurality of blades is configured to pump the fluid as a result of rotation of the rotor assembly.
However, Danner teaches thrust bearings(106,108) wherein the thrust disk(204) comprises a plurality of blades(blades of 204) at said outer periphery, wherein the plurality of blades(blades of 204) is configured to pump the fluid as a result of rotation of the rotor assembly(Figs. 2-5; Col. 3-Col. 4).
Danner is considered to be analogous to the claimed invention of Cunningham because they are in the same field of magnetic drive systems. Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have further modified Cunningham wherein the thrust disk comprises a plurality of blades at said outer periphery, wherein the plurality of blades is configured to pump the fluid as a result of rotation of the rotor assembly, as taught by Danner. One would be motivated to do this in order to improve thermal management and system reliability to increase efficiency.
Regarding claim 9/1, Cunningham in view of Danner teaches the magnetic thrust bearing of claim 1.
Danner further teaches wherein the blades (blades of 204) are smaller than the thrust disk(204)(Fig. 3, shows the blades do not exceed the disk diameter and are clearly smaller than the disk itself).
Danner is silent in particular a height of the blades (blades of 204) is 5-15% of a diameter of the thrust disk. But, it would have been obvious to one having ordinary skill in the art at the time the invention was made to have the height of blades be 5-15% of the diameter of the thrust disk, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art . In re Aller, 105 USPQ 233. One would be motivated to do this in order to increase structural integrity.
Regarding claim 10/1, Cunningham in view of Danner teaches the magnetic thrust bearing of claim 1.
The combination does not explicitly teach wherein a width of the blades is 70-100% of a thickness of the thrust disk. But, it would have been obvious to one having ordinary skill in the art at the time the invention was made to have the width of blades be 70-100% of the thickness of the thrust disk, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art . In re Aller, 105 USPQ 233. One would be motivated to do this in order to increase structural integrity.
Regarding claim 11/1, Cunningham in view of Danner teaches the magnetic thrust bearing of claim 1.
Danner further teaches wherein the blades (blades of 204) have a blade profile with a first concavity and a second concavity(Fig. 3, pressure and suction side to each blade is inherent in vaned structure for moving fluid), the first concavity being oriented toward a first side of the thrust disk(204) and the second concavity being oriented toward a second side of the thrust disk (204)(Fig. 3, inherent that blades are exposed to fluid on both sides and they have to orient towards one axial side of the thrust disk).
Regarding claim 12/1, Cunningham in view of Danner teaches the magnetic thrust bearing of claim 1.
Danner further teaches wherein the blades (blades of 204) are mounted on the thrust disk (204), in particular by dovetail coupling(Fig. 3, blades are mounted on thrust disk). The use of “in particular” in the claim renders it non-limiting exemplary language, so other mounting techniques are not excluded. Therefore, the blade-mounting limitation of claim 12 is taught, and claim 12 is rendered obvious).
Regarding claim 13/1, Cunningham in view of Danner teaches a rotary machine comprising a magnetic thrust bearing according to claim 1.
Danner teaches wherein the rotor assembly (202, 204) of the magnetic thrust bearing is coupled with a shaft(202) of the rotary machine(Fig. 3).
Regarding claim 14/13, Cunningham in view of Danner teaches the rotary machine of claim 13.
Cunningham further teaches wherein the rotary machine is an expander-compressor system(Para[0003], compressors, turbines, and generators are all expander-compressor systems).
Regarding claim 15/14, Cunningham in view of Danner teaches the rotary machine of claim 14.
Cunningham further teaches wherein the rotor assembly (319) of the magnetic thrust bearing (318) is mounted to a shaft (307) mechanically coupling an expander (Para[0003]; turbine = gas expander) of the expander-compressor system and a compressor (Para[0003]), compressor ) of the expander- compressor system.
Regarding claim 16/13, Cunningham in view of Danner teaches the rotary machine of claim 13.
Cunningham further teaches wherein the magnetic thrust bearing (318) is positioned inside a casing (Fig. 3, machine housing shown housing all rotating machine assembly) of the machine and the fluid outlet (515-517) of the magnetic thrust bearing (319) is fluidly coupled with an inner chamber (335, 330;internal cavities) of the casing (machine housing).
Regarding claim 17/13, Cunningham in view of Danner teaches the rotary machine of claim 13.
Cunningham further teaches comprising a cooling system(Fig. 5) wherein a fluid is recirculated in a closed loop configuration only by means of the magnetic thrust bearing (319)(Para[0067-0072, shows the closed loop of the cooling fluid).
Claim(s) 2-8 is/are rejected under 35 U.S.C 103 as being unpatentable over CUNNINGHAM(US20110052432A1) in view of DANNER(US6309188B1) and further in view of EMERSON(US5529464A).
Regarding claim 2/1, Cunningham in view of Danner teaches the magnetic thrust bearing of claim 1.
Neither Cunningham or Danner expressly discloses grooves on the thrust disk.
However, Emerson teaches wherein the thrust disk(88) comprises further a plurality of grooves (154) at said first side, wherein the plurality of grooves (154) is configured to pump the fluid as a result of rotation of the rotor assembly(Fig. 4a).
Emerson is considered to be analogous to the claimed invention of Cunningham in view of Danner because they are in the same field of magnetic drive systems. Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have further modified Cunningham in view of Danner wherein the thrust disk comprises further a plurality of grooves at said first side, wherein the plurality of grooves is configured to pump the fluid as a result of rotation of the rotor assembly, as taught by Emerson. One would be motivated to include grooves on the thrust disk to enhance fluid pumping as a predictable design choice which increase cooling efficiency.
Regarding claim 3/2, Cunningham in view of Danner and Emerson teaches the magnetic thrust bearing of claim 1.
Cunningham further teaches wherein the stator assembly(323) comprises preferably at least two magnet assemblies(318), a first magnet assembly(318) facing the first side, a second magnet assembly(318) facing the second side(Fig. 3);
wherein the magnetic thrust bearing has at least one fluid inlet and a fluid outlet(515-517 define fluid inlets and outlets), and is configured to be cooled by the fluid entering into the at least one fluid inlet, flowing from the fluid inlet to the fluid outlet, and exiting from the fluid outlet; wherein at least the first side of the thrust disk is configured to receive the fluid at an inner periphery of the thrust disk, and discharge the fluid at the outer periphery of the thrust disk(Figs. 5a-5d, Para[0069-0071]).
Regarding claim 4/3, Cunningham in view of Danner and Emerson teaches the magnetic thrust bearing of claim 3.
Cunninghame in view of Danner and Emerson teaches wherein the magnetic thrust bearing (Cunningham, 318) has a first fluid inlet (Cunningham, 515-517) for the fluid at the first side of the thrust disk (Cunningham, 319) and a second fluid inlet (Cunningham, 515-517) for the fluid at the second side of the thrust disk (Cunningham, 319), and wherein the thrust disk (Emerson, 88) comprises a first plurality of grooves (Emerson, 154) on the first side and a second plurality of grooves (Emerson, 154) on the second side, wherein the first plurality of grooves (Emerson, 154) and the second plurality of grooves (Emerson, 154) are configured to pump the fluid as a result of rotation of the rotor assembly.
Regarding claim 5/2, Cunningham in view of Danner and Emerson teaches the magnetic thrust bearing of claim 2.
Emerson further teaches wherein the grooves(154) extend: from an area around an inner periphery(near fluid feed holes 158) of the thrust disk (88) to an area around the outer periphery (near annular channel 160) of the thrust disk (88)(Fig. 4a), or from an area around an inner periphery (near fluid feed holes 158) of the thrust disk (88) to an area around an intermediate region (region between fluid feed holes and annular channel 160) of the thrust disk (88)), or from an area around an intermediate region (region between fluid feed holes and annular channel 160) of the thrust disk (88)) of the thrust disk (88) to an area around the outer periphery (near annular channel 160) of the thrust disk (88)(Fig. 4a).
Regarding claim 6/2, Cunningham in view of Danner and Emerson teaches the magnetic thrust bearing of claim 2.
Emerson further teaches wherein the thrust disk (88) comprises a first plurality of grooves(154) and a second plurality of grooves(154) on a first side of the thrust disk (88) and/or on a second side of the thrust disk (88), the first plurality being at an inner area of the side(near holes 158) and the second plurality being at an outer area of the side(near outer channel 160)(Fig. 4a).
Regarding claim 7/2, Cunningham in view of Danner and Emerson teaches the magnetic thrust bearing of claim 2.
Emerson further teaches wherein the grooves (154) are curved-shaped(Fig. 4a, spiral grooves are inherently curved).
Regarding claim 8/2, Cunningham in view of Danner and Emerson teaches the magnetic thrust bearing of claim 2.
Emerson further teaches wherein the grooves (154) are configured so that at least part of the fluid flows in a preferential direction defined by the grooves (154)(Fig. 4a, spiral grooves inherently impose a directional flow component).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MOHAMMED QURESHI whose telephone number is (571)-272-8310. The examiner can normally be reached on 8:30 AM - 6:00 PM.
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/MOHAMMED AHMED QURESHI/Examiner, Art Unit 2834
/TULSIDAS C PATEL/Supervisory Patent Examiner, Art Unit 2834