DETAILED ACTION
Response to Amendment
The Amendment filed December 10, 2025 has been entered. Claims 1 – 6 and 8 – 21 are pending in the application with claims 9 – 11, 14, 16 and 18 – 20 being withdrawn, claim 21 being newly added and claim 7 being cancelled.
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.
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.
Claims 1, 3 – 6, 8, 12 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Smith, Jason D. (US 2019/0264683 – herein after Jason; cited by applicant on IDS dated 12/12/2023) in view of Smith, Jason D (US 2016/0108910 – herein after Smith; cited by applicant on IDS dated 08/08/2025).
In reference to claim 1, Jason teaches a closure element (102, see fig. 6B) for a fluid end (200; see figs. 5-7) of a reciprocating pump (see ¶9), the closure element being installable within a bore segment (horizontal bore segment that receives closure element 102, see figs. 6A-6B) of a casing (housing) of the fluid end (200) to substantially close the bore segment (to substantially close the right end of the segment), the closure element comprising:
a closure section (labeled “c.s.” in fig. A below); and
a seating section (labeled “s.s.” in fig. A below) extending radially beyond the closure section to define a shoulder (labeled “S” in fig. A below), wherein the shoulder is configured to engage a surface (surface defined by wall portion labeled “w1” in fig. A below) of the casing facing a pressure chamber (chamber/space within bore of the segment; this space constitutes a pressure chamber since it is within the reciprocating pump that pressurizes fluid and is further labeled “c” in fig. A below for convenience) of the fluid end while the closure section extends away (in → direction) from the pressure chamber into the bore segment.
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Fig. A: Edited fig. 6B of Jason to show claim interpretation.
Jason remains silent on the closure element, wherein the shoulder and at least one of the closure section or the seating section has a non-circular cross-sectional shape.
However, Smith teaches a similar fluid end (see figs. 3A-7) of a reciprocating pump (see ¶34) comprising: a similar segment (segment defining port 238) with a non-circular closure element (202; 202 is considered to be non-circular because of presence of machined flats 234; see fig. 4 and ¶32; also see ¶30: “As shown in FIG. 4 and described above, cover 202 includes a distal end 208 and a proximal end 210. Distal or insertion end 208 of cover 202 is preferably sized and shaped to be sealingly engaged within an access port of an industrial machine (e.g., a mud pump). While distal and proximal ends 208, 210 of cover 202 are shown as generally circular, it should be understood by those having ordinary skill that any shape or profile of access port may be accommodated using a similar or correspondingly shaped cover 202”).
Since applicant in the instant application has not disclosed any criticality associated with “non-circular” shape (for instance, see ¶5-¶8 of filed specification, where applicant use phrase such as “may” while describing advantages related to non-circular/ovular shape), it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the shape of the closure element (which comprises the shoulder and at least one of the closure section or the seating section) in Jason’s fluid end for a non-circular shape as taught by Smith as a matter of design choice since such a modification would have involved a mere change in shape of the components (as recognized by Smith in ¶30). One of ordinary skill in the art, furthermore, would have expected Jason’s pump to perform equally well with claimed non-circular shape for the closure element.
In reference to claim 3, Jason, as modified, teaches the closure element, wherein the seating section (labeled “s.s.” in fig. A above) is proximate an interior surface (surface corresponding to left face of 102, see fig. 6B) and the closure section (labeled “c.s.” in fig. A above) is proximate an exterior surface (surface corresponding to right face of 102, see fig. 6B).
In reference to claim 4, Jason, as modified, teaches the closure element, wherein each of the seating section and the closure section has the non-circular cross-sectional shape (in view of proposed modification discussed above in claim 1).
In reference to claim 5, Jason, as modified, teaches the closure element, wherein the non-circular cross-sectional shape of the seating section is smaller than the non-circular shape of the closure section (see fig. A above: the asserted seating section’s length is smaller (i.e. length in ↔ direction) than the asserted closure section’s length; thus, the claimed feature is present in the modified closure element).
In reference to claim 6, Jason, as modified, teaches the closure element, wherein only one of the seating section or the closure section includes the non-circular cross-sectional shape (in view of proposed modification discussed above in claim 1).
In reference to claim 8, Jason, as modified, teaches the closure element, wherein the closure section (labeled “c.s.” in fig. A above) defines a seal channel (118c; see fig. 4 and ¶36) adjacent or proximate to the shoulder (labeled “S” in fig. A above).
In reference to claim 12, Jason, as modified, teaches a closure assembly (102+126+124, see fig. 6B) formed with the closure element (102) of claim 1, the closure assembly further comprising: a retaining assembly (126+124) that is coupleable to an exterior surface (right surface, see fig. 6B) of the closure element (102).
In reference to claim 13, Jason, as modified, teaches the closure assembly, wherein the retaining assembly (126+124) is configured to be disposed entirely within the bore segment of the casing of the fluid end when the closure element (102) is installed within the bore segment of the casing of the fluid end to substantially close the bore segment.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Jason in view of Smith and evidenced by Bruestle et al. (US 2016/0230729 - herein after Bruestle; cited by applicant on IDS dated 08/08/2025).
Jason, as modified, remains silent on the closure element, wherein the non-circular cross-sectional shape is any shape (in view of Smith’s disclosure in ¶30).
Jason, as modified, remains silent on the closure element, wherein the non-circular cross-sectional shape is an extended ovular shape that lacks corners.
However, Bruestle evidences a non-circular shape of "elongated ovular that lacks corners" provided to a component (43, see fig. 7 and claim 11) of an assembly (42) inserted into its corresponding oval shaped bore (44) in a housing (46).
Since applicant in the instant application has not disclosed any criticality associated with "extended ovular shape that lacks corners” (for instance, see ¶5-¶8 of filed specification, where applicant use phrase such as "may" while describing advantages related to extended ovular shape), it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to have the non-circular shape in the modified Jason’s closure element as an extended ovular shape that lacks corners as a matter of design choice since such a modification would have involved a mere change in shape of the component (as recognized by Smith in ¶30). One of ordinary skill in the art, furthermore, would have expected Jason's pump to perform equally well with claimed extended ovular shape for the closure element.
Claims 15 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Gamboa et al. (US 4,861,241 – herein after Gamboa) in view of Smith, Jason D (US 2016/0108910 – herein after Smith; cited by applicant on IDS dated 08/08/2025).
In reference to claim 15, Gamboa teaches a closure assembly (22+18’+18+16, see fig. 2) for a fluid end (10, see fig. 1) of a reciprocating pump (8, see fig. 1), at least a portion of the closure assembly (portion for instance being component 22) being installable within a segment (horizontal bore segment that receives closure element 22, see fig. 2) of a casing (12) of the fluid end (10) to substantially close the segment, the closure assembly comprising:
a closure element (22) that extends from an interior surface (surface corresponding to left face of 22 in view of fig. 2) to an exterior surface (surface corresponding to right face of 22 in view of fig. 2), wherein the closure element (22) comprises:
a closure section (section/portion defining lip 31, see fig. 3; also, labeled “c.s.” in fig. B below) proximate the exterior surface; and
a seating section (labeled “s.s.” in fig. B below) proximate the interior surface and extending radially beyond the closure section to define a shoulder (labeled “S” in fig. B below), wherein the shoulder is configured to engage a surface (surface in circled region in fig. B below) of the casing (12) facing a pressure chamber (chamber/space within opening/bore in which 22 is received; this space constitutes a pressure chamber since it is within the reciprocating pump that pressurizes fluid) of the fluid end;
a retaining element (18’) that is coupleable to the exterior surface (surface corresponding to right face of 22 in view of fig. 2) of the closure element (22); and
a seal assembly (see fig. B below) that is positionable between the closure element (22) and the retaining element (18’), proximate the closure element, wherein coupling the retaining element to the closure element retains the seal assembly therebetween.
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Fig. B: Edited fig. 2 of Gamboa to show claim interpretation.
Gamboa remains silent on the closure assembly, wherein the shoulder and at least one of the closure section or the seating section have a non-circular cross-sectional shape.
However, Smith teaches a similar fluid end (see figs. 3A-7) of a reciprocating pump (see ¶34) comprising: a similar segment (segment defining port 238) with a non-circular closure element (202; 202 is considered to be non-circular because of presence of machined flats 234; see fig. 4 and ¶32; also see ¶30: “As shown in FIG. 4 and described above, cover 202 includes a distal end 208 and a proximal end 210. Distal or insertion end 208 of cover 202 is preferably sized and shaped to be sealingly engaged within an access port of an industrial machine (e.g., a mud pump). While distal and proximal ends 208, 210 of cover 202 are shown as generally circular, it should be understood by those having ordinary skill that any shape or profile of access port may be accommodated using a similar or correspondingly shaped cover 202”; a PHOSITA would recognize that if the cover 202 is of non-circular shape, the retainer 204 (received in bore 244 and in contact with cover 202), and the entirety of the segment (in which cover 202 and retainer 204 are received/inserted) must also necessarily define a corresponding non-circular cross-section to receive, secure, and engage with the non-circular cover).
Since applicant in the instant application has not disclosed any criticality associated with “non-circular” shape (for instance, see ¶5-¶8 of filed specification, where applicant use phrase such as “may” while describing advantages related to non-circular/ovular shape), it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the shape of the closure assembly (which comprises the shoulder and at least one of the closure section or the seating section) and entirety of its corresponding segment in Gamboa’s fluid end for a non-circular shape as taught by Smith as a matter of design choice since such a modification would have involved a mere change in shape of the components (as recognized by Smith in ¶30). One of ordinary skill in the art, furthermore, would have expected Gamboa’s pump to perform equally well with claimed non-circular shape for the closure assembly.
In reference to claim 21, Gamboa, as modified, teaches the closure assembly, wherein both the closure section and the seating section have the non-circular cross-sectional shape (in view of proposed modification discussed above in claim 15).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Gamboa in view of Smith and Jian et al. (US 2021/0355927 – herein after Jian).
Gamboa teaches the closure assembly, wherein the seal assembly comprises a seal (see fig. B above) and the seal being proximate the closure element (22).
Gamboa remains silent on the closure assembly, wherein the seal assembly comprises a single seal carrier and the single seal carrier being positioned between the seal and the retaining element.
However, Jian teaches a sealing assembly (4, see fig. 1) for a closure element (2, see fig. 1) in a fluid end, wherein the sealing assembly comprises (see fig. 2) a seal (soft packing 19) and a single seal carrier (hard packing 20), (in view of figs. 1-2) the seal (19) being proximate the closure element (2) and the single seal carrier (20) being positioned between the seal (19) and the retaining element (3).
Thus, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify the seal assembly of Gamboa for the seal assembly that comprises a seal and a single seal carrier as taught by Jian for the purpose of having any one or all of the beneficial effects: “the sealing form of O-ring or D-ring in the prior art is replaced by the suction packing seal assembly between the suction gland and the valve housing; there is no need to open grooves for filling the O-ring or D-ring in the processing of the suction gland or the valve housing; good sealability; in view of the current continuous operation with high pressure and large displacement, in the actual use of the hydraulic end assembly, the sealing of the suction gland by the suction packing seal assembly can meet the sealing requirements under the current increasing pressure and fluid flushing more, compared with the O-ring or D-ring; reducing the abrasion of the suction gland or/and the valve housing; further effectively prolonging the service life of the suction gland or/and the valve housing”, as recognized by Jian (see ¶12).
Response to Arguments
Applicant’s arguments, dated 12/10/2025, with respect to the independent claims have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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.
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/CHIRAG JARIWALA/Examiner, Art Unit 3746
/ESSAMA OMGBA/Supervisory Patent Examiner, Art Unit 3746