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 .
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 1-2, 4-5, 10-11, 13-14 and 17-22 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.
Regarding claim 1, the claim recites that the first and second hydraulic cylinders are elongate. The applicant’s specification provides no guidance on how to interpret this term. Accordingly, those of skill in the art are not apprised of the intended scope of this term and these claims are therefore indefinite. The examiner will interpret this limitation as requiring a cylinder which is longer in at least one dimension than in a second direction.
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) 1-5,9-14,17-23 and 25-26 is/are rejected under 35 U.S.C. 103 as being unpatentable over US Pre-Grant Publication 2018/0030978 to McCarthy (McCarthy hereinafter) in view of U.S. Patent 4,390,322 to Budzich (Budzich) and WO90/08897 to Christiansen et al. (Christiansen).
Regarding claim 1, as best understood by the examiner, McCarthy teaches a fluid compressor (150) operable to compress a working fluid, said multi- cylinder fluid compressor comprising: a first gas compression cylinder (180), divided into first (181a) and second (181b) axially aligned compression chambers by a first reciprocating gas piston (182), each of the first and second compression chambers of the first gas compression cylinder having an inlet (250) and an outlet (251); first (187a) and second (187b) elongate hydraulic cylinders positioned at opposite ends of the multi-cylinder fluid compressor, with the first and second compression cylinders therebetween to axially drive the common piston rod; wherein the first and second hydraulic cylinders are adapted to be actuated by a hydraulic fluid supply system (1160) to reciprocally drive the common piston rod and thereby the first reciprocating gas piston. Furthermore, McCarthy teaches first and second hydraulic pistons (152a, 152b), as well as first and second buffer chambers (195a, 195b).
McCarthy does not teach the limitation of a second gas compression cylinder. Budzich teaches another hydraulically driven gas compressor, and particularly teaches that a multistage compressor (10) may be driven by a hydraulic actuator (23, 24), the compressor including a first (16, 17) and a second (20) chamber for compression in order to provide high pressure ratio (col. 1, ln. 47-55). Budzich further teaches elongate cylinders (11, 13, which are elongated in at least one dimension each). Budzich teaches that these chambers are coaxially aligned, have corresponding inlets and outlets, and are operatively connected via a single common piston rod (between 19 and 21). One of ordinary skill in the art would have found it obvious before the effective filing date of the application to provide another cylinder of either the type taught by Budzich or that taught by McCarthy in order to obtain a multistage compressor capable of higher pressure ratios. In the case of the chamber taught by McCarthy, these cylinders would have third and fourth chambers analogous to the first and second of McCarthy. Alternatively, the arrangement of the first and second cylinders with respect to the hydraulic actuator is considered to constitute the mere rearrangement of known elements with no substantive change in their purpose or operation. See MPEP 2144.04 VI. C.
McCarthy also does not teach that the outlets of the gas cylinders are positioned at a bottom thereof. Christiansen teaches that an outlet is provided at each of a top (13) and a bottom (23) of a cylinder of a multiphase hydrocarbon compression system, and that the bottom is configured to trap sand (page 5, first paragraph). One of ordinary skill in the art would have found it obvious before the effective filing date of the application to use dual outlets, including an outlet at a bottom of the cylinder of McCarthy as taught by Christiansen in order to trap sand in the system of McCarthy.
Regarding claim 2, Budzich teaches seal devices (178, 179) on the piston rod and on the first piston (173, 178), as well as on the second piston (180, 181).
Regarding claim 4, McCarthy teaches first and second hydraulic piston seal devices (196a, 196b).
Regarding claim 5, as discussed above, Budzich teaches a multistage fluid compressor.
Regarding claim 10, McCarthy teaches that the first and second buffer chamber may at least be vented (see paragraph 127: “air within buffer chamber may be exchanged with the external environment”).
Regarding claim 11, the inlets are placed to the tops and bottoms of the corresponding cylinders as illustrated in McCarthy.
Regarding claim 13, Budzich teaches that the inlets and outlets may be at least partially radial (see e.g. Fig. 3).
Regarding claim 14, McCarthy teaches axial inlets (250) and outlets (251).
Regarding claim 17, as best understood by the examiner, the cylinders as taught by McCarthy and Budzich would be substantially adjacent, and would be connected by a connector plate (e.g. 205 in Budzich).
Regarding claim 18, Budzich teaches a variable volume pocket (18) fluidly connected with the third compression chamber.
Regarding claim 19, McCarthy teaches check valves (e.g. 1250, see paragraph 148).
Regarding claim 20, McCarthy teaches the use of wear rings (paragraph 92).
Regarding claim 21, Budzich teaches three compression cylinders, which when implemented in the fashion disclosed by McCarthy would create fifth and sixth axially aligned compression chambers having the recited features discussed above with respect to the first and second chambers and associated elements.
Regarding claim 22, McCarthy teaches the hydraulic fluid supply system (1160).
Claim(s) 23 and 25-26 is/are rejected under 35 U.S.C. 103 as being unpatentable over US Pre-Grant Publication 2018/0030978 to McCarthy (McCarthy hereinafter) in view of U.S. Patent 4,390,322 to Budzich (Budzich), WO90/08897 to Christiansen et al. (Christiansen) and US Pre-Grant Publication 2009/0133674 to Lee et al. (Lee).
Regarding claim 1, McCarthy teaches a fluid compressor (150) operable to compress a working fluid, said multi- cylinder fluid compressor comprising: a first gas compression cylinder (180), divided into first (181a) and second (181b) axially aligned compression chambers by a first reciprocating gas piston (182), each of the first and second compression chambers of the first gas compression cylinder having an inlet (250) and an outlet (251); first (187a) and second (187b) elongate hydraulic cylinders positioned at opposite ends of the multi-cylinder fluid compressor, with the first and second compression cylinders therebetween to axially drive the common piston rod; wherein the first and second hydraulic cylinders are adapted to be actuated by a hydraulic fluid supply system (1160) to reciprocally drive the common piston rod and thereby the first reciprocating gas piston. Furthermore, McCarthy teaches first and second hydraulic pistons (152a, 152b), as well as first and second buffer chambers (195a, 195b).
Regarding claim 23, McCarthy does not teach the limitation of a second gas compression cylinder. Budzich teaches another hydraulically driven gas compressor, and particularly teaches that a multistage compressor (10) may be driven by a hydraulic actuator (23, 24), the compressor including a first (16, 17) and a second (20) chamber for compression in order to provide high pressure ratio (col. 1, ln. 47-55). Budzich further teaches elongate cylinders (11, 13, which are elongated in at least one dimension each). Budzich teaches that these chambers are coaxially aligned, have corresponding inlets and outlets, and are operatively connected via a single common piston rod (between 19 and 21). One of ordinary skill in the art would have found it obvious before the effective filing date of the application to provide another cylinder of either the type taught by Budzich or that taught by McCarthy in order to obtain a multistage compressor capable of higher pressure ratios. In the case of the chamber taught by McCarthy, these cylinders would have third and fourth chambers analogous to the first and second of McCarthy.
McCarthy also does not teach that the outlets of the gas cylinders are positioned at a bottom thereof. Christiansen teaches that an outlet is provided at each of a top (13) and a bottom (23) of a cylinder of a multiphase hydrocarbon compression system, and that the bottom is configured to trap sand (page 5, first paragraph). One of ordinary skill in the art would have found it obvious before the effective filing date of the application to use dual outlets, including an outlet at a bottom of the cylinder of McCarthy as taught by Christiansen in order to trap sand in the system of McCarthy.
Additionally regarding the method in particular, McCarthy teaches delivering a flow of gas or vapor to a first cylinder (180) from a reservoir (204), operating the piston to compress the gas or vapor, Budzich teaches providing the outlet flow of the cylinder to a second cylinder for further compressive operation and delivery. The previously applied references do not explicitly teach pumping from a tank. Lee teaches compressing gas from a tank (1) in a compressor (6) to e.g. provide fuel for a tanker (paragraphs 2, 21). One of ordinary skill in the art would have found it obvious before the effective filing date of the application to use the compressor of McCarthy to compress fuel from a tank as taught by Lee in order to provide power for a tanker.
Regarding claims 25 and 26, McCarthy teaches ceasing operation based on upstream or line pressure (paragraph 143).
Response to Arguments
Applicant's arguments filed 2 February 2026 have been fully considered but they are not persuasive.
With respect to the argument that Budzich allegedly lacks elongate hydraulic cylinders, the examiner is not persuaded. Fundamentally, the applicant has not established any particular meaning for the term in the specification or in the record as a whole. As such, the examiner holds that any cylinder which is longer in one dimension than another qualifies as elongate for the purposes of claim construction under the broadest reasonable interpretation. Since both McCarthy and Budzich teach such cylinders, the examiner cannot agree that this feature distinguishes the claimed invention over the prior art.
More generally, the art, as exemplified by the references relied on herein, is well aware of the components of hydraulically driven compressors. The mere rearrangement or duplication of these components, such as by adding a second cylinder or providing separated hydraulic cylinders instead of an intermediate double acting actuator does not constitute any particular contribution over the prior art. See MPEP 2144.04 VI. B. and VI. C.
Finally, regarding applicant’s arguments directed toward a tank, the examiner holds that this limitation is taught by Lee, and is therefore obvious.
In view of these holdings, the examiner maintains that the claimed invention is obvious.
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 PHILIP E STIMPERT whose telephone number is (571)270-1890. The examiner can normally be reached Monday-Friday, 8a-4p.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Chelsea Stinson can be reached on 571-270-1744. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/PHILIP E STIMPERT/Primary Examiner, Art Unit 3746 22 May 2026
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