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 Objections
Claim 9, 17 are objected to because of the following informalities:
Claim 9 appears to contain a scrivener’s error, the claim includes the limitation “cylindrical bore section has having a generally consistent.”
Claim 17 appears to contain a scrivener’s error, the claim includes the limitation “The downhole check valve of clam 16 wherein…”
Appropriate correction is required.
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.
Claim 4-6, 9-15 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.
Claims 4, 13 include, or depend from claims that include, the limitation(s): "the ring member” There is insufficient antecedent basis for the limitation “the ring member” in the claim. It is unclear if claim 4, 13 was intended to introduce a ring member or if claim 4, 13 was intended to depend from claim 2, 12 which introduced “a ring member” and further limit the ring member of claim 2, 12 as claim 4, 13 introduces additional limitations related to the ring member.
Claim 5 includes the limitation(s): "a seventh point” and “an eighth point”. Claim 5 depends from claim 1. Claim 1 introduces first through fourth points. It is unclear what the fifth and sixth points in claim 5 are. It is unclear if claim 5 was intended to depend from claim 2, which introduced fifth and sixth points.
Claims 5-6, 9-15 include, or depend from claims that include, the limitation(s): "generally”. The term “generally” is a relative term which renders the claim indefinite. The term “generally” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. It is unclear how much deviation from the claimed shapes modified by the term “generally” would still be considered to read on the claim.
Clarification and/or correction are required. No new matter may be entered. The claims will be read and examined as best understood.
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 is/are, as best understood, rejected under 35 U.S.C. 103 as being unpatentable over Kritzler (US 20110203805) in view of Haines (US 20210062926).
Regarding claim 1, Kritzler teaches: A downhole check valve for controlling flow of gas through a flowline of a gas lift system, the downhole check valve comprising:
(a) a valve housing having an inlet (Kritzler near 46), an outlet (Kritzler near 66), and an internal flow path (Kritzler near 50/22) extending from the inlet to the outlet, the valve housing comprising:
i) a dart sub (Kritzler 54), the dart sub having a bore passing axially therethrough;
ii) an inlet sub (Kritzler near 54/46) coupled the dart sub, the inlet sub having a bore (Kritzler 50) passing axially therethrough and an end surface (Kritzler near 62), the inlet sub bore having at least one cross-sectional diameter;
(b) a valve seat (Kritzler 62) located within the valve housing, and held (Kritzler see Fig. 2/3) between the first end surface of the inlet sub and another surface (Kritzler 54 near 62), the valve seat defining a valve seat expanding opening (Kritzler tapered portion 62) including a section having an internal cross-sectional diameter (Kritzler tapered portion 62) that increases axially from a first point (Kritzler 62 near 50) along the axis of the valve housing to a second point (Kritzler 62 near 22) along the valve housing axis, wherein the first point is closer to the inlet than is the second point;
(c) a dart (Kritzler comprising 58) located within valve housing, the dart including:
i) a dart seating surface (Kritzler [0011]), the dart seating surface including a section having a cross-section that increases axially from a third point (Kritzler upper portion of 58, near 62) along the axis of the valve housing to a fourth point (Kritzler 58 near 60), wherein the third point is closer to the inlet than is the fourth point; wherein, the dart is movable (Kritzler [0011]) between an open position permitting fluid flow through the valve housing and a closed position blocking fluid flow through the valve, and wherein, when the dart is in its open position,
the smallest cross-sectional diameter of the valve seat expanding opening is less (Kritzler see Fig. 2-4) than the smallest cross-sectional diameter of the inlet sub.
But does not describe the material of the seat or expressly state:
the valve seat being formed from a resilient material
Haines teaches a downhole check valve for controlling gas comprising: a dart sub (Haines comprising 25), an inlet sub (Haines 22), and a valve seat (Haines 22) comprising a resilient material (Haines [0022]).
It would have been considered obvious to one of ordinary skill in the art, before the effective filing date (AIA ) or at the time the invention was made (Pre-AIA ), to have modified Kritzler to include forming the seat from a resilient material as Kritzler teaches a generic seat material and using the known resilient material of Haines yields the predictable result of allowing the operator form a seal at a desired location within the borehole. All the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded predictable results to one of ordinary skill in the art, before the effective filing date (AIA ) or at the time the invention was made (Pre-AIA ).
Regarding claim 5, the combination of Kritzler and Haines teaches: The downhole check valve of claim 1 wherein the dart further comprises:
(a) an intermediate, generally cylindrical outer surface section (Kritzler below reference character 60 above 50, Fig. 3); and
(b) a tail surface (Kritzler near 60) including a section having a cross-section that decreases (Kritzler decrease from max OD near reference character 60) from a seventh point along the axis of the valve housing to an eighth point, wherein the seventh point is closer to the inlet than is the eighth point.
Claim(s) 3, 16-18 is/are, as best understood, rejected under 35 U.S.C. 103 as being unpatentable over the combination of Kritzler and Haines in view of Messick (US 20100108326).
Regarding claim 3, the combination of Kritzler and Haines teaches: The downhole check valve of claim 1 including using a spring (Kritzler [0011]) but does not provide the structural details of the biasing member or expressly state:
wherein, the dart further comprises a dart post, wherein the dart post extends from the dart at a location further from the inlet than is the dart seating surface, and wherein the check valve further comprises a spring at least partially surrounding the dart post.
Messick teaches a gas lift valve assembly comprising a dart (Messick 521) wherein, the dart further comprises a dart post (Messick near 526), wherein the dart post extends (Messick Fig. 10) from the dart at a location further from the inlet than is the dart seating surface, and wherein the check valve further comprises a spring (Messick 526) at least partially surrounding the dart post.
It would have been considered obvious to one of ordinary skill in the art, before the effective filing date (AIA ) or at the time the invention was made (Pre-AIA ), to have modified the combination to include a spring disposed inside a recessed portion of the stem for purposes of exerting an upward force on the valve element to bias the valve closed.
Regarding claim 16, Kritzler teaches: A downhole check valve for controlling flow of gas through a flowline of a gas lift system, the downhole check valve comprising:
a. a valve housing having an inlet (Kritzler near 46), an outlet (Kritzler near 66), and an internal fluid flow path (Kritzler near 50/22) extending from the inlet to the outlet, the valve housing comprising an inlet housing (Kritzler near 54/46), the inlet housing defining a first opening (Kritzler near 46) comprising the valve housing inlet and second opening (Kritzler near 66), the second opening being located at an end of the inlet housing opposite the first opening;
b. a valve seat (Kritzler 62) located within the valve housing, the valve seat defining a valve seat expanding opening (Kritzler tapered portion 62) including a section having a cross-sectional diameter (Kritzler tapered portion 62) that increases axially from a first point along the axis of the valve housing to a second point along the valve housing axis, wherein the first point is closer (Kritzler see Fig. 2/3) to the inlet than is the second point;
c. a dart (Kritzler comprising 58) located within valve housing, the dart including:
i. a dart seating surface (Kritzler [0011]) having a cross-section that increases axially from a third point (Kritzler upper portion of 58, near 62) along the axis of the valve housing to a fourth point Kritzler 58 near 60), wherein the third point is closer to the inlet than is the fourth point; the smallest cross-sectional diameter of the valve seat opening is less (Kritzler see Fig. 2-4) than the cross sectional diameter of the inlet housing second opening
But does not describe the material of the seat or expressly state:
the valve seat being formed from a resilient material
Haines teaches a downhole check valve for controlling gas comprising: a dart sub (Haines comprising 25), an inlet sub (Haines 22), and a valve seat (Haines 22) comprising a resilient material (Haines [0022]).
It would have been considered obvious to one of ordinary skill in the art, before the effective filing date (AIA ) or at the time the invention was made (Pre-AIA ), to have modified Kritzler to include forming the seat from a resilient material as Kritzler teaches a generic seat material and using the known resilient material of Haines yields the predictable result of allowing the operator form a seal at a desired location within the borehole. All the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would have yielded predictable results to one of ordinary skill in the art, before the effective filing date (AIA ) or at the time the invention was made (Pre-AIA ).
The combination does include using a spring (Kritzler [0011]) but does not provide the structural details of the dart / biasing member or expressly state:
ii. an internal cylindrical cavity having a closed end, a closed end surface, an open end, and an open end ledge surface;
d. a valve stem member at least partially positioned within the second housing, the valve stem member including a post that extends into the dart internal cylindrical cavity, the valve stem member further including a ledge surface, and
e. a resilient member positioned entirely within the dart internal cylindrical cavity and between the dart closed end surface and a surface of the post; wherein, when the downhole check valve is in its open position, the smallest cross-sectional diameter of the valve seat opening is less than the cross sectional diameter of the inlet housing second opening and the dart open end ledge surface at least substantially abuts the ledge surface of the valve stem member.
Messick teaches a gas lift valve assembly comprising a dart (Messick 521) wherein, ii. an internal cylindrical cavity (Messick near 526) having a closed end (Messick near 521/526), a closed end surface (Messick near 521/526), an open end (Messick near 530), and an open end ledge surface (Messick near 530);
d. a valve stem member at least partially positioned within the second housing, the valve stem member including a post (Messick inside 526) that extends (Messick Fig. 10) into the dart internal cylindrical cavity, the valve stem member further including a ledge surface, and
e. a resilient member (Messick 526) positioned entirely within the dart internal cylindrical cavity and between the dart closed end surface and a surface (Messick near 526) of the post; and the dart open end ledge surface at least substantially abuts (Messick near 530) the ledge surface of the valve stem member.
It would have been considered obvious to one of ordinary skill in the art, before the effective filing date (AIA ) or at the time the invention was made (Pre-AIA ), to have modified the combination to include a spring disposed inside a recessed portion of the stem for purposes of exerting an upward force on the valve element to bias the valve closed.
Regarding claim 17, the combination of Kritzler, Haines, and Messick and teaches: The downhole check valve of claim 16 wherein the valve housing further comprises a dart sub (Kritzler 54) coupled the inlet housing, the dart sub having a bore passing axially therethrough, and wherein the dart is located (Kritzler Fig. 2-3) within the dart sub in its open position.
Regarding claim 18, the combination of Kritzler, Haines, and Messick teaches: The downhole check valve of claim 17 wherein the valve housing further comprises an outlet sub (Kritzler near threads 54 / near 66) coupled to the dart sub.
Allowable Subject Matter
Claim 2, 7-8, 19-20 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim 9 would be allowable if rewritten or amended to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action.
Claim 4, 6, 10-15 would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
Prior Art
The following prior art made of record and not relied upon is considered pertinent to Applicant's disclosure.
Carlisle (US 2931385) teaches a downhole check valve for controlling flow of gas through a flowline of a gas lift system, the downhole check valve comprising: an inlet housing, a valve housing, a dart, a seat, and a biasing element.
Mahmoud (US 20100319924) teaches a downhole check valve comprising: an inlet housing, a valve housing, a dart, a valve seat, and a biasing element.
Salihbegovic (US 20130032226) teaches a downhole check valve for controlling flow of gas through a flowline of a gas lift system, the downhole check valve comprising: a valve housing, a dart sub, an inlet sub, a valve seat, a valve ring, wherein the dart comprises an internal flow path.
McVay (US 20050189107) teaches a downhole check valve for controlling flow of gas through a flowline of a gas lift system, the downhole check valve comprising: (a) a valve housing having an inlet, an outlet, and an internal flow path extending from the inlet to the outlet, the valve housing comprising: i) a dart sub, the dart sub having a bore passing axially therethrough; ii) an inlet sub coupled the dart sub, the inlet sub having a bore passing axially therethrough and an end surface, the inlet sub bore having at least one cross-sectional diameter; (b) a valve seat located within the valve housing, the valve seat being formed from a resilient material and held between the first end surface of the inlet sub and another surface, the valve seat defining a valve seat expanding opening including a section having an internal cross-sectional diameter that increases axially from a first point along the axis of the valve housing to a second point along the valve housing axis, wherein the first point is closer to the inlet than is the second point; (c) a dart located within valve housing, the dart including: i) a dart seating surface, the dart seating surface including a section having a cross-section that increases axially from a third point along the axis of the valve housing to a fourth point, wherein the third point is closer to the inlet than is the fourth point; wherein, the dart is movable between an open position permitting fluid flow through the valve housing and a closed position blocking fluid flow through the valve.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to David Carroll whose telephone number is (571)272-4808. The examiner can normally be reached M-F 2:00-10:00 PM EDT.
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/David Carroll/ Primary Examiner, Art Unit 3674