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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on July 13, 2026 has been entered.
The July 13, 2026 request included a preliminary amendment of July 13, 2026 which amended claims 1, 10 and 11.
Claim Objections
Claims 1, 10 and 11 are objected to because of the following informalities: each of the noted claims have been amended to set forth “wherein the first axial compressor unit and the second axial compressor unit are both overhung on opposing ends of the same first pinion shaft”. This limitation has already been set forth (see for example cl. 1 lines 9-13, claim 10 lines 7 and 8, and claim 11 lines 9 and 11) so this limitation should be deleted as redundant. Appropriate correction is required.
Claim 10 is objected to because of the following informalities: in line 9 “second compressor unit” should be “second centrifugal compressor unit” (see line 19). Appropriate correction is required.
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 1-4, 10 and 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.
Claims 1, 10 and 12 have been amended to set forth: “wherein the first pinion shaft only supports axial compressor units and the second pinion shaft only supports centrifugal compressor units”. The applicant references paragraph [0038] of USPAP 2024/0309878 which sets forth:
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Nothing in this teaching limits that first pinion shaft to “only” supporting “axial compressor units and the second pinion shaft only supports centrifugal compressor units.” Therefore, this newly added limitation represents new matter.
Claims not specifically mentioned are rejected since they depend from one of the above claims.
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.
Claim 10 is 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 10 is vague and indefinite because in lines 12 and 13 it is unclear which of the previous first axial compressor unit (line 7), the first centrifugal compressor unit (line 9), the second axial compressor unit (line 7) and the second centrifugal compressor unit (lines 9 & 19) are being referenced by “the first compressor unit” and “the second compressor unit” in lines 12 and 13.
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, 4, 10 and 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over Schierl (USPN 3,001,692) in view of Bauermeister et al (DE 1959754, cited by Applicant), as evidenced by Shin et al (USPN 9,745,986), and further in view of Fujino et al (USPN 4,219,306)
With regards to claims 1 and 11, Schierl discloses an integrally geared compressor (see Fig. 1), comprising: a gear casing (10); a bull gear (4) supported for rotation in the gear casing; a plurality of pinion (5,7) shafts (6- first pinion shaft, 8-second pinion shaft) supported for rotation in the gear casing and coupled to the bull gear; a first (and only) compressor unit (11,13) and a second (and only) compressor unit (12,14) overhung (clearly shown in Fig. 1) on opposing ends of one (6-the first pinion shaft) of the pinon shafts, the first compressor and the second compressor each comprising a gas inlet and a gas outlet; a first (and only) centrifugal compressor unit (15,17) overhung on another of pinion shafts (8-the second pinion shaft); a line (line is given its broadest reasonable interpretation and in the Schierl reference is the flow pathway including the nozzle 25, see Fig. 1 & 2, the intercooler 26 and the nozzle 28) connecting the gas outlet of the first compressor unit directly to the gas inlet of the second compressor unit (the inlet and the outlets of all the compressors in Schierl are clearly shown in Fig. 1); and, Schierl discloses a first centrifugal compressor unit (15, 17) drivingly coupled to a first end of the second pinion shaft (7, 8) in an overhung fashion; and a second (and only) centrifugal compressor unit (16, 18) drivingly coupled to a second end of the second pinion shaft in an overhung fashion, wherein the respective pinion on the first pinion shaft and the second pinion shaft are configured to cause a first rotational speed (inherent) for the first axial compressor unit and the second compressor unit (12,14) and a second rotational speed (inherent) for the first centrifugal compressor unit (15,17) and the second centrifugal compressor unit (16,18). Schierl also discloses that the compressor units coupled to the pinion shafts are arranged in sequence to stepwise compress fluid. Schierl further discloses that the first and second pinion shafts have bodies extending from the first (right) side of the gear casing to a second (left) side of the gear casing, as set forth in claim 11.
Schierl does not disclose that the first compressor unit overhung on the first end of the first pinion shaft is an axial compressor unit or that the first rotational speed is different than the second rotational speed, that the second compressor is an axial compressor and that the first axial compressor unit has a volumetric flow rate that is higher than the other compressor units.
Bauermeister et al discloses a similar four stage compressor including a bull gear driving two pinion shafts having compressor units mounted in overhung fashion on the ends of the pinion shafts, further the first compressor stage is an axial compressor unit (11, 12, 13) mounted in an overhung fashion at a first end of a pinion shaft (7, 4, 10) and is the only compressor mounted at the end of the pinion shaft; and, as made clear by the different sizes/diameters of the pinion gears 3 and 4, the first rotational speed of pinion shaft 7 is different than the second rotational speed of pinion shaft 8 (the figure of Bauermeister et al clearly shows the diameter of pinion 4 being larger than the diameter of pinion 3). Fujino et al discloses a similar sequential compression system driven by a gearbox; and at col. 6 lines 7-10 teaches that the flow rate at the entrance or succeeding stages is approximately 50% of the preceding stage, see also col. 1 lines 33-43. Therefore the first compressor would have a volumetric flow rate that is higher than the other compressor units.
At the time of the effective filing date of the application it would have been obvious to one of ordinary skill in the art to substitute an axial compressor unit, as taught by Bauermeister et al, for the first (11,13) compressor unit, as taught by Schierl, as the first compressor stage and similarly substitute an axial compressor for the second (12,14) compressor unit of Schierl, since axial compressors and centrifugal compressors are recognized as equivalence for their use in the rotary non-positive displacement compression art (as evidence of this see Shin et al at col. 4 lines 4-9 which discloses that in a gear driven multi-stage compressor both axial compressors and centrifugal compressors maybe utilized as the compression stages) and selection of either of these known equivalents to provide the first and the second compression stages would be within the level of ordinary skill in the art (Note MPEP 2144.06) dependent upon the desired flow rates, pressures attained and the parts available for a particular application. Further, at the time of the effective filing date of the application it would have been obvious to one of ordinary skill in the art to select a gear ratio for the pinions in the Schierl geared multi-stage compressor which would result in the speeds of pinion shafts being different, such as was done in the Bauermeister et al integrally geared multi-stage compressor, in order to obtain the predictable result of attaining the correct driving speed for a particular axial compressor or centrifugal compressor design, see KSR Int' l Co. V. Teleflex Inc. 550 U.S.__, 82 USPQ 2d 1385 (Supreme Court 2007) (KSR). Further, it would have been obvious to make the volumetric flow rate of the first compressor be the highest flow rate so that continuous compression is maintained through the stages.
With regards to claim 4, Bauermeister et al discloses wherein the first axial compressor unit (11, 12, 13) is a multi-stage axial compressor unit (the drawing clearly discloses the axial compressor being a multi-stage unit).
With regards to claim 10, Schierl discloses an integrally geared compressor (see Fig. 1), comprising: a gear casing (10); a bull gear (4) supported for rotation in the gear casing; a plurality of pinion (5,7) shafts (6- first pinion shaft, 8-second pinion shaft) supported for rotation in the gear casing and coupled to the bull gear; a first compressor unit (11,13) and a second compressor unit (12,14) overhung (clearly shown in Fig. 1) on opposing ends of one (6) of the pinon shafts, the first compressor and the second compressor each comprising a gas inlet and a gas outlet; a first centrifugal compressor unit (15,17) and a second centrifugal compressor unit (16, 18) overhung on another of pinion shafts (8); a line (line is given its broadest reasonable interpretation and in the Schierl reference is the flow pathway including the nozzle 25, see Fig. 1 & 2, the intercooler 26 and the nozzle 28) connecting the gas outlet of the first compressor unit directly to the gas inlet of the second compressor unit (the inlet and the outlets of all the compressors in Schierl are clearly shown in Fig. 1); wherein the respective pinion on the first pinion shaft and the second pinion shaft are configured to cause a first rotational speed (inherent) for the first compressor unit (11,13) and the second compressor unit (12,14) and a second rotational speed (inherent) for the first centrifugal compressor unit and the second centrifugal compressor unit. Schierl also discloses that the compressor units coupled to the pinion shafts are arranged in sequence to stepwise compress fluid.
Schierl does not disclose that the first rotational speed is different than the second rotational speed, that the first and second compressor units on pinion shaft 6 are axial compressor units, or that the first axial compressor unit has a volumetric flow rate that is higher than the other compressor units.
Bauermeister et al discloses a similar four stage compressor including a bull gear driving two pinion shafts having compressor units mounted in overhung fashion on the ends of the pinion shafts, further the first rotational speed of pinion shaft 7 is different than the second rotational speed of pinion shaft 8 (the figure of Bauermeister et al clearly shows the diameter of pinion 4 being larger than the diameter of pinion 3 and thus teaches of the different speeds). Bauermeister et al discloses a similar four stage compressor where the first compressor stage is an axial compressor unit (11, 12, 13) mounted in an overhung fashion at a first end of a pinion shaft (7, 4, 10) and is the only compressor mounted at the end of the pinion shaft.
Fujino et al discloses a similar sequential compression system driven by a gearbox; and at col. 6 lines 7-10 teaches that the flow rate at the entrance or succeeding stages is approximately 50% of the preceding stage, see also col. 1 lines 33-43. Therefore the first compressor would have a volumetric flow rate that is higher than the other compressor units.
At the time of the effective filing date of the application it would have been obvious to one of ordinary skill in the art to select a gear ratio for the pinions in the Schierl integrally geared compressor which would result in the speeds of pinion shafts being different, such as was done in the Bauermeister et al integrally geared multi-stage compressor, in order to obtain the predictable result of attaining the correct driving speed for a particular axial impeller or centrifugal compressor design, see KSR Int' l Co. V. Teleflex Inc. 550 U.S.__, 82 USPQ 2d 1385 (Supreme Court 2007) (KSR). Further, it would have been obvious to make the volumetric flow rate of the first compressor be the highest flow rate so that continuous compression is maintained through the stages. Also, at the time of the effective filing date of the application it would have been obvious to one of ordinary skill in the art to substitute an axial compressor unit, as taught by Bauermeister et al, for the first (11,13) compressor unit of Schierl and to similarly substitute and axial compressor for the second (12,14) compressor unit of Schierl, since axial compressors and centrifugal compressors are recognized as equivalence for their use in the rotary non-positive displacement compression art (as evidence of this see Shin et al at col. 4 lines 4-9 which discloses that in a gear driven multi-stage compressor both axial compressors and centrifugal compressors maybe utilized as the compression stages) and selection of either of these known equivalents to provide the first and the second compression stages would be within the level of ordinary skill in the art (Note MPEP 2144.06) dependent upon the desired flow rates, pressures attained and the parts available for a particular application.
Claim(s) 2 and 3 is/are rejected under 35 U.S.C. 103 as being unpatentable over Schierl in view of Bauermeister et al, as evidenced by Shin et al, and Fujino et al as applied to claim 1 above, and further in view of Nab et al (USPN 9,512,849).
With regards to claim 2, as set forth above Schierl in view of Bauermeister et al, evidenced by Shin et al, and Fujino et al discloses the invention of claim 1 substantially as claimed and additionally discloses that the gas outlet (in Schierl Fig. 1 the connection from casing 14 to duct 29) of the first axial compressor unit is a radial gas outlet. Bauermeister et al do not disclose that the gas inlet of the first axial compressor unit is an axial gas inlet.
Nab et al discloses a series of axial compressors driven via a gear train with a first of the axial compressor stages 6 having an axial inlet 26.
At the time of the effective filing date of the application it would have been obvious to one having ordinary skill in the art to move the radial inlet of Bauermeister et al axial compressor to be an axial inlet, as taught by Nab et al, since this is a well-known arrangement for such a compressor and because it has been held that rearranging parts of an invention involves only routine skill in the art. In re Japinske, 86 USPQ 70. Please note that in the instant application the applicant has not disclosed any criticality for the claimed limitations.
With regards to claim 3, the Examiner previously gave official notice that axial compressors having a radial outlet with a vaned diffuser are well known, which was not challenged. This is taken as an admission that this material is prior art. At the time of the effective filing date of the application it would have been obvious to include a diffuser in order to further compress the fluid.
Response to Arguments
Applicant's arguments filed July 13, 2026 have been fully considered but they are not persuasive. The applicant argues that there is no reason to combine, that none of the cited art teaches a first axial compressor and a second axal compressor overhung on opposite ends of a pinion shaft, the applicant argues that for some reason in the instant application centrifugal and axial compressors are not interchangeable and that the substitution of one for the other would fundamentally alter the principle of operation of the device; that Bauermeister teaches away from the second end of the first pinion shaft having an axial compressor because:
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And lastly the applicant argues that the cited references do not teach any arrangement "wherein the first pinion shaft only supports axial compressor units and the second pinion shaft only supports centrifugal compressor units".
In response to applicant’s argument that there is no teaching, suggestion, or motivation to combine the references, the examiner recognizes that obviousness may be established by combining or modifying the teachings of the prior art to produce the claimed invention where there is some teaching, suggestion, or motivation to do so found either in the references themselves or in the knowledge generally available to one of ordinary skill in the art. See In re Fine, 837 F.2d 1071, 5 USPQ2d 1596 (Fed. Cir. 1988), In re Jones, 958 F.2d 347, 21 USPQ2d 1941 (Fed. Cir. 1992), and KSR International Co. v. Teleflex, Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007). In this case, EVERY reference applied teaches multiple rotary non-positive displacement compressors driven by gear trains where the individual non-positive displacement pumps are overhung on opposite ends of pinion shafts; the proposed modification is a mere substitution of one equivalent compressor type for another is well within the skill level of one of ordinary art and would have been done to achieve the required conditions of a particular application with available equipment.
With regards to the argument that none of the cited art teaches a first axial compressor and a second axal compressor overhung on opposite ends of a pinion shaft the applicant is correct, which is why no anticipation rejections were made. Further, In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
With regards to the arguments that in the instant application centrifugal and axial compressors are not interchangeable and that the substitution of one for the other would fundamentally alter the principle of operation of the device; and that Bauermeister teaches away from the second end of the first pinion shaft having an axial compressor, these arguments are merely assertions by the applicant. There is no reason or showing by the applicant why in the instant application centrifugal and axial compressors cannot be substituted for one another despite that fact that these types of non-positive displacement pumps are routinely substituted for one another and operate under similar well-known principles, note Shin et al. It is this well-known equivalence which the applicant relies on to even be able to claim an axial compressor at each end of the pinion shaft. It is noted that the original drawings do not shown this feature and that paragraph [0038] provides two sentences that essentially stated that axial compressors may be substituted for the shown centrifugal compressor and that this was considered enough to enable a person in the art to make the now claimed invention and to show that applicant had possession of the now claimed invention. There are no “fundamental conditions” in the applicant’s disclosure that would make centrifugal and axial compressors incompatible as the applicant asserts. If there were some fundamental condition then it would raise a question of whether the applicant has possession of the claimed invention since no particular teaching of how an axial compressor would be designed or adjusted to overcome these asserted fundamental conditions. Similarly, the Bauermeister reference and the cited text does not teach away. The cited text is a recitation of the benefits of multi-stage compression which each of the cited references are. The cited text does not make any statements about the requirement, or set forth limitations, that the second compressor of Bauermeister et al must be a centrifugal compressor as opposed to an axial compressor (Examiner’s Note: in the remarks section at the last paragraph of page 10 the applicant makes reference to “Bauermeister at 4”, it is unclear what 4 represents; page 4, line 4, claim 4?).
Lastly, with regards to the argument that the cited references do not teach any arrangement "wherein the first pinion shaft only supports axial compressor units and the second pinion shaft only supports centrifugal compressor units" this material represents new matter as set forth in the rejections under 35 USC 112(a) and, as set forth in the above rejections, the references teach or make obvious this limitation.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHARLES G FREAY whose telephone number is (571)272-4827. The examiner can normally be reached Mon - Fri: 8:00 - 5:00.
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/CHARLES G FREAY/ Primary Examiner, Art Unit 3746
CGF
August 13, 2026
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