DETAILED ACTION
Response to Amendment
The Amendment filed April 8, 2026 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 Claims 1 – 6 and 8 – 21 are pending in the application with claims 9 – 11, 14, 16 and 18 – 20 being withdrawn and claim 7 being cancelled.
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 5 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 5 recites the limitation “wherein the non-circular cross-sectional shape of the seating section is smaller than the non-circular cross-sectional shape of the closure section” in lines 1-3. In view of claim 1, the seating section (438, in fig. 8A) extends in or alongside the pumping chamber (308, see fig. 4). It is unclear as to how this seating section has the claimed non-circular cross-sectional shape “smaller” than that of the closure section (438, in fig. 8A). For examination purposes, it is understood that certain portion/region (for instance, shoulder 436 in view of fig. 8A) of the seating section has the non-circular cross-sectional shape smaller (in axial direction) than that of the closure section.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1, 3, 12 and 13 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by St. Michel et al. (US 2007/0140869 – herein after Michel).
In reference to claim 1, Michel discloses a closure element (shaded component; see fig. A below) for a fluid end (22; see fig. 3) of a reciprocating pump (see abstract), the fluid end comprising a casing (see fig. A below) having a first segment (“S1”) and a second segment (“S2”) that intersect one another to form an edge surface (see fig. A below) and at least partially define a pumping chamber (64) within the casing, the closure element (shaded component; see fig. A below) being installable within the first segment (“S1”) to substantially close the first segment, the closure element comprising:
a closure section (labeled “c.s.” in fig. A below) configured to extend within a portion of the first segment; and
a seating section (labeled “s.s.” in fig. A below) extending radially beyond the closure section to define a shoulder (see fig. A below), wherein the shoulder is configured to engage the edge surface of the casing such that the seating section extends in or alongside the pumping chamber (64).
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Fig. A: Edited fig. 3 of Michel to show claim interpretation.
In reference to claim 3, Michel discloses the closure element, wherein the seating section (“s.s.”; see fig. A above) extends radially beyond the closure section such that the shoulder (see fig. A above) extends radially beyond the first segment to engage the edge surface of the casing and close the first segment.
In reference to claim 12, Michel discloses a closure assembly (see fig. B below) formed with the closure element (“shaded component”) of claim 1, the closure assembly further comprising: a retaining assembly (see fig. B below) that is coupleable to an exterior surface (right surface) of the closure element such that (in view of fig. A above and fig. B below) the closure section extends between the retaining assembly and the seating section, and the seating section extends radially beyond the exterior surface of the closure element.
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Fig. B: Edited fig. 3 of Michel to show claim interpretation.
In reference to claim 13, Michel discloses the closure assembly, wherein the retaining assembly (see fig. B above) is configured to be disposed entirely within the first segment (“S1”; see fig. A above) of the casing of the fluid end when the closure element (“shaded component”) is installed within the first segment of the casing of the fluid end to substantially close the first segment.
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.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Michel in view of Ramos et al. (US 2014/0331856 – herein after Ramos) and evidenced by Smith, Jason D (US 2016/0108910 – herein after Smith).
Michel remains silent on the closure element having an extended ovular shape that lacks corners.
However, Ramos teaches (see fig. C below) a non-circular shape of “extended ovular” provided to a component (“closure element”) inserted into its corresponding oval shaped bore in a pump housing (12). This “extended ovular” shape lacks corners.
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Fig. C: Edited fig. 1 of Ramos to show claim interpretation.
Smith further evidences a similar fluid end (see figs. 3A-7) of a reciprocating pump (see ¶34) comprising: a closure element (200, see fig. 3A) comprising a non-circular cross-sectional shape (shape that is not circular) corresponding to a non-circular shape of corresponding segment (segment defining port 238 and bore 244, see fig. 7) [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 “extended ovular” shape that lacks corners (for instance, see ¶5-¶8 and 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 have the shape for the closure element in Michel’s fluid end as “extended ovular” as taught by Ramos as a matter of design choice since such a modification would have involved a mere change in shape of the components (as further evidenced by Smith above). One of ordinary skill in the art, furthermore, would have expected Michel’s fluid end to perform equally well with this claimed extended ovular shape that lacks corners.
Claims 4 – 6 are rejected under 35 U.S.C. 103 as being unpatentable over Michel in view of Smith, Jason D (US 2016/0108910 – herein after Smith).
Regarding claim 4,
Michel remains silent on the closure element wherein each of the seating section and the closure 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 closure element (200, see fig. 3A) comprising a non-circular cross-sectional shape (shape that is not circular) corresponding to a non-circular shape of corresponding segment (segment defining port 238 and bore 244, see fig. 7) [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” cross-sectional shape for each of the seating section and the closure section (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 Michel’s fluid end to have each of the seating section and the closure section in a non-circular cross-sectional 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 Michel’s fluid end to perform equally well with claimed non-circular cross-sectional shape for each of the seating section and the closure section.
Regarding claim 5,
Michel, as modified, teaches the closure element wherein the non-circular cross-sectional shape of the seating section is smaller than the non-circular cross-sectional shape of the closure section [as evident from fig. A above: the shoulder region in the asserted seating section “s.s.” has the non-circular cross-sectional shape smaller (in ↔ direction) than the non-circular cross-sectional shape of the closure section “c.s.”].
Regarding claim 6,
Michel remains silent on the closure element wherein only one of the seating section or the closure section includes 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 closure element (200, see fig. 3A) comprising a non-circular cross-sectional shape (shape that is not circular) corresponding to a non-circular shape of corresponding segment (segment defining port 238 and bore 244, see fig. 7) [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” cross-sectional shape for only one of the seating section and the closure section (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 Michel’s fluid end for having only one of the seating section and the closure section to include a non-circular cross-sectional 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 Michel’s fluid end to perform equally well with claimed non-circular cross-sectional shape for only one of the seating section and the closure section.
Claims 8, 15 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Michel in view of Jian et al. (US 2021/0355927 – herein after Jian).
Regarding claim 8,
Michel remains silent on the closure element, wherein the closure section defines a seal channel adjacent or proximate to the shoulder.
However, Jian teaches a fluid end, comprising a suction packing seal assembly (4; see figs. 1-2) inserted between a closure element (2) and a wall (wall portion in casing 1) and extending toward (→ in view of fig. 1) an external surface of a casing (1).
It would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify Michel’s closure section for defining a seal channel in order to provide a seal taught by Jian since Jian states (see ¶12) “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”. With respect to the location of the seal channel or seal itself adjacent or proximate to the shoulder, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to define the seal channel for Jian’s seal in the closure section such that the seal channel is adjacent or proximate to the shoulder in the modified fluid end of Michel since it has been held that rearranging parts of an invention involves only routine skill in the art. In re Japikse, 86 USPQ 70. Please note that in the instant application, applicant has not disclosed any criticality of locating or defining the seal channel as claimed.
Thus, Michel, as modified, teaches the closure element, wherein the closure section (“c.s.”; see fig. A above) defines a seal channel (for seal of Jian) adjacent or proximate to the shoulder (see fig. A above).
Regarding claim 15,
Michel teaches a closure assembly (see fig. B above) for a fluid end (22; see fig. 3) of a reciprocating pump (see abstract), the fluid end comprising a casing (see fig. A above) with a first segment (“S1”) and a second segment (“S2”) that intersect to define at least a portion of a pumping chamber (64) within the casing, the closure assembly comprising:
a closure element (shaded component; see fig. A below) that extends from an interior surface (surface corresponding to left face of the closure element in view of fig. A above) to an exterior surface (surface corresponding to right face of the closure element in view of fig. A above), wherein the closure element comprises:
a closure section (labeled “c.s.” in fig. A above) proximate the exterior surface and configured to extend within a portion of the first segment (“S1”); and
a seating section (labeled “s.s.” in fig. A above) proximate the interior surface, extending radially beyond the exterior surface and the closure section, and configured to extend in or alongside the pumping chamber (64);
a retaining element (labeled as “retaining assembly” in fig. B above) that is coupleable to an exterior surface (right surface) of the closure element.
Michel remains silent on the closure assembly, comprising a seal assembly that is positionable between the seating section and the retaining element and against the closure section while the retaining element is coupled to the closure element.
However, Jian teaches a fluid end, comprising a suction packing seal assembly (4; see figs. 1-2) inserted between a closure element (2) and a wall (wall portion in casing 1) and extending toward (→ in view of fig. 1) an external surface of a casing (1).
It would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to modify Michel’s closure section for provision of a seal assembly taught by Jian since Jian states (see ¶12) “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”. With respect to the location of the seal assembly between the seating section and the retaining element and against the closure section, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to position Jian’s seal assembly between the seating section and the retaining element and against the closure section while the retaining element is coupled to the closure element in the modified fluid end of Michel since it has been held that rearranging parts of an invention involves only routine skill in the art. In re Japikse, 86 USPQ 70. Please note that in the instant application, applicant has not disclosed any criticality of locating the seal assembly between the seating section and the retaining element and against the closure section.
Regarding claim 17,
Michel, as modified, teaches the closure assembly, wherein the seal assembly (4, see Jian’s figs. 1-2) comprises a seal (hard packing 20) and a single seal carrier (soft packing 19) and the seal surrounding the closure element and the single seal carrier being positioned between the seal and the seating section of the closure element [in the modified closure assembly: 1) Jian’s seal 20 surrounds the Michel’s closure element (“shaded component” in fig. A above); and 2) Jian’s single seal carrier 19 is positioned between the Jian’s seal 20 and Michels’s seating section (“s.s.” in fig. A above) of the closure element].
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Michel in view of Jian and Smith, Jason D (US 2016/0108910 – herein after Smith).
Michel remains silent on the closure element wherein both the seating section and the closure 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 closure element (200, see fig. 3A) comprising a non-circular cross-sectional shape (shape that is not circular) corresponding to a non-circular shape of corresponding segment (segment defining port 238 and bore 244, see fig. 7) [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” cross-sectional shape for both the seating section and the closure section (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 Michel’s fluid end to have both the seating section and the closure section in a non-circular cross-sectional 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 Michel’s fluid end to perform equally well with claimed non-circular cross-sectional shape for both the seating section and the closure section.
Response to Arguments
Applicant’s arguments, dated 04/08/2026, with respect to independent claims have been considered but they are moot. The amendment to the independent claims changed the scope of the claim. As a result, the prior arts have been re-evaluated and re-applied to these claims, in view of newly found reference of Michel and Ramos.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHIRAG JARIWALA whose telephone number is (571)272-0467. The examiner can normally be reached M-F 8 AM-5 PM.
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/CHIRAG JARIWALA/Examiner, Art Unit 3746
/ESSAMA OMGBA/Supervisory Patent Examiner, Art Unit 3746
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