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 4 us objected to because of the following informalities: claim 4 ends in a double period, one should be eliminated. 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.
Claims 3, 4, 5, and 18 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.
The term “about” in claims 3 and 4, is a relative term which renders the claim indefinite. The term “about” 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 if about were for example, to include +/- 5%, 10%, 15%, etc. .
The term “substantially” in claim 5 is a relative term which renders the claim indefinite. The term “substantially” 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. Examiner is unclear if the term substantially is defining the degree of how planer or perpendicular the surfaces are, or an allusion to the amount of the shroud which is planer or perpendicular, which in particular is critical since some of the front and back shroud are expressly not planer as they are raised per claim 1.
Claim 18 recites, “pumping vanes extending between the inner main face of the back shroud,” Examiner notes, the phrase between requires two points for something to be located between, but applicant has merely provided “the back shroud” and no other element for the vanes to extend between.
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) 1-2, 5-7, 9-10, 12-14, 16-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over US 4,759,690 to Deschamps et al. (D1) in view of US 2019/0316596 to Munts et al. (M1).
In Re Claim 1:
D1 teaches:
A centrifugal slurry pump impeller((Col. 1, ll. 7-12 notes the pump impeller is for mixed fluid/solid i.e. slurry) including:
A back shroud(Fig. 4, 22, 26, 28, 29, 27) and a front shroud(38, 32) each with opposed inner (back 26, 28, 29, 27 and front 32) and outer (back 22, 42, 43 and front 39, 38, 32) faces and a peripheral edge (back, 26, 26.1 and front 34, 32) and a central axis (through nose 27),
The front shroud including an impeller inlet (33) and the back shroud including an impeller nose (27) raised from the inner face of the back shroud facing the impeller inlet and in line with the central axis, [See Figures 2 for inlet, 3 for back face nose and 4 for axis of rotation alignment]
A plurality of pumping vanes(20) extending between the inner main faces of the back and front shroud, the pumping vanes being disposed in spaced apart relation, each pumping vane including opposed main side faces, a leading edge(Fig. 3, 41) in the region of the central axis, and a trailing edge (outermost edges in Fig. 3) in the region of the outer peripheral edges of the back and front shrouds with a passageway(Fig. 3 shows four passages between vanes) between adjacent pumping vanes,
Wherein a surface of the inner face of at least one of the front and back shrouds includes a raised portion(Fig. 3-4, 29) located between the regions of adjacent pumping vanes. [Figures 3 and 4 show the upraised region(29) as compared to blades(45) and the remaining height of the shroud(28, 26) Figure 3 shows this region extends between portions beyond the front most point defining a leading edge of each blade. See D1 Annotated Fig. 3 below.]
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Annotated D1 Fig. 3
D1 does not teach:
Blended regions in each passageway between each of the main side faces of the pumping vanes and the inner faces of the front and back shrouds.
M1 teaches:
It is well-known with slurry impellers (Page 1, ¶1 notes mixed flow impellers), to use a blended region (Fig. 3C, 32) around each blade against the front and back shrouds (Fig. 2, 11, 12). [Page 4, ¶47-49 note the fillets can be applied between blades and front and back shrouds.] Using the Fillet regions and blending with the blades can provide better flow regions less sensitivity to flow angles, and improved wear characteristics. [Page 3, ¶42-44.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of D1 to include a fillet/blended region at the edge of each blade towards the front and back shrouds as taught by M1, with the expectation of successfully providing better flow regions with less sensitivity to flow angles and improved wear characteristics. [Page 3, ¶42-44.] This would yield the limitation of an upraised region between blended regions in each passageway between each of the main side faces of the pumping vanes and the inner faces of the front region.
In Re Claims 2, 5-7, 9-10, 12-14, 16-17:
D1 as modified by M1 teaches:
The centrifugal slurry pump impeller according to claim 1, wherein:
(Claim 2) each passageway extends from an inner region of the passageway beginning adjacent the leading edge of the plurality of pumping vanes to an outer region of the passageway wherein the outer region ends at the outer peripheral edge of the front and back shrouds and wherein the raised portion is located in the inner region of the passage. [It can be seen in Fig. 3 of D1, that the raised portion (29) of each shroud is in the inner region of the passageway. Fig. 3 also shows each passageway extends from an inlet to an outlet portion.]
(Claim 5) the inner surfaces of the front and back shroud in the outer region are substantially planer and are in ap lane that is substantially perpendicular to the central axis. [D1, Fig. 4 d4 shows substantially planer inner and outer surfaces of the front and back shrouds, and that they are perpendicular to a projecting axis extending along the rotation axis.]
(Claim 6) one of the opposed side faces of the adjacent pumping vanes is a pressure side face and the other of the opposed side faces is a suction side face, wherein an apex of the raised portion is located closer to the suction side face than the pressure side face. [It can be seen in Second Annotated D1 Fig. 3 image below, which shows the suction side face is closer to the inner radius edge of section (29) which as can be seen in D1, Fig. 4, is the apex or higher side.]
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Second Annotated D1 Figure 3
(Claim 7) the raised portion includes a convex surface. [D1, Fig. 4 shows the upraised portion is convex and curved outward.]
(Claim 9) the raised portion provides a surface on the inner face of the back and/or front shroud which continues from the blended region associated with one of the opposed side faces to the blended region of the other of the opposed side faces of the adjacent pumping vanes. [It can be seen in D1, Fig. 3, that each section 29 extends entirely from the adjacent main sides of each front vane regions.]
(Claim 10) claim 6, the apex of the raised portion is located adjacent the suction side face to which it is closest so as to modify the flow of slurry through the passageway in use and thereby reduce turbulence and/or inhibit the formation of vortices formed adjacent the inner main face of the back and/or front shroud. [See Claim 6 and Second Annotated D1 Figure 3, note the highest portion of the region between each blade is located closest to the suction side.]
(Claim 12) the raised porting is located on the inner face of the back shroud. [D1 Fig. 4 shows the back face has the upraised region.]
(Claim 13) the raised portion is located in each one of the passageways located between adjacent pumping vanes. [D1, Fig. 3 and 4 show the upraised region is section (29) and that there is a section 29 between each of the blades.]
(Claim 14) claim 6, the apex of the raised portion is spaced from the blended region located between the main side faces of the pumping vanes and the inner face of the back and/or front shroud. [Fig. 3 of D1 shows the apex is the centermost portion of each section which is spaced from the main side faces of the pumping vanes on the front or back shrouds.]
(Claim 16) the impeller has no more than six pumping vanes. [D1 Fig. 3 shows four blades.]
(Claim 17) the impeller has four pumping vanes. [D1 Fig. 3 shows four blades.]
In Re Claim 18:
D1 teaches:
A centrifugal slurry pump impeller((Col. 1, ll. 7-12 notes the pump impeller is for mixed fluid/solid i.e. slurry) including:
A back shroud(Fig. 4, 22, 26, 28, 29, 27) with an inner (back 26, 28, 29, 27) and outer (back 22, 42, 43) face and an outer peripheral edge (back, 26, 26.1) and a central axis (through nose 27),
A plurality of pumping vanes(20) extending between the inner main face of the back shroud, the pumping vanes being disposed in spaced apart relation, each pumping vane including opposed main side faces, a leading edge(Fig. 3, 41) in the region of the central axis, and a trailing edge (outermost edges in Fig. 3) in the region of the outer peripheral edges of the back shroud with a passageway(Fig. 3 shows four passages between vanes) between adjacent pumping vanes,
Wherein a surface of the inner face of at least one of the front and back shrouds includes a raised portion(Fig. 3-4, 29) located between the regions of adjacent pumping vanes. [Figures 3 and 4 show the upraised region(29) as compared to blades(45) and the remaining height of the shroud(28, 26) Figure 3 shows this region extends between portions beyond the front most point defining a leading edge of each blade. See D1 Annotated Fig. 3 above.]
D1 does not teach:
Blended regions in each passageway between each of the main side faces of the pumping vanes and the inner faces of the back shroud.
M1 teaches:
It is well-known with slurry impellers (Page 1, ¶1 notes mixed flow impellers), to use a blended region (Fig. 3C, 32) around each blade against the front and back shrouds (Fig. 2, 11, 12). [Page 4, ¶47-49 note the fillets can be applied between blades and front and back shrouds.] Using the Fillet regions and blending with the blades can provide better flow regions less sensitivity to flow angles, and improved wear characteristics. [Page 3, ¶42-44.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of D1 to include a fillet/blended region at the edge of each blade towards the front and back shrouds as taught by M1, with the expectation of successfully providing better flow regions with less sensitivity to flow angles and improved wear characteristics. [Page 3, ¶42-44.] This would yield the limitation of an upraised region between blended regions in each passageway between each of the main side faces of the pumping vanes and the inner faces of the front region.
Claims 3, 4, and 11 is/are rejected under 35 U.S.C. 103 as being obvious over D1 and M1, in further view of US 2011/0158795 to Burgess et al. (B1).
In Re Claim 3:
D1 as modified by M1 in claim 1 teaches:
The centrifugal slurry pump of claim 1, wherein the raised portion (which the region to adjust from nose height to final shroud height) extends from the inner region adjacent the leading edge of the plurality of pumping vanes.
D1 as modified by M1 in claim 1 does not teach:
The raised portion extends and ends about three quarters along the length of the passageway.
Examiner notes:
The instant Application is silent as to any specific advantage for the raised portion extending to about three quarters along the length of the passage. Further in so far as this claim is definite the office notes it no so clear as to how close to three quarters length is required to be about three quarters.
B1 teaches:
A modification for slurry pump raised regions. [Page 1, ¶4.] The nose region that extends along blade length and sides as a raised portion(Fig. 1, I nose) by using larger nose radius of curvature (Inr and Fr). In particular the radius of curvature of the transition Fr, which begins at the blade leading edge, which extends from the nose to the outer diameter of the impeller can be for example from 0.2 to 0.75, or 0.2 to 0.52, or 0.33, or 0.22, or 0.1. Thus, the radius of curvature would result in a nose raised region transition extending to ¾ of the impeller or about half of the impeller radius since the distance of 0.75 of the diameter is larger than the diameter of just the length of the passages. [Page 2, ¶18-25.] This has the advantage of improving smooth flow patterns, minimizing shock losses at the entrances to the passages, and control the amount of turbulence as long as possible through the passageway by extending the raised region into it. [Page 4, ¶65-67.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the nose transition curvature region of D1(28, 29) to extend further into the blade passage by enlarging the radius of transition curvature as taught by B1, with the expectation of successfully improving the smooth flow patterns, minimizing shock loses at the entrances to the passages, and control the amount of turbulence as long as possible through the passageway by extending the raised region into it. [Page 4, ¶65-67.] This would yield the transition regions (29) of D1 extending further into the blade region.
Before the effective filing date of the invention, it would have been an obvious matter of design choice to a person of ordinary skill in the art to increase the raised region of D1 as modified by B1, to about three quarters the length of the vane passage, because Applicant has not specifically disclosed that the distance of three quarters of the passage extension of the raised region provides an advantage, is used for a particular purpose, or solves a stated problem over the normal raised region extension. One of ordinary skill in the art, furthermore, would have expected Applicant’s invention to perform equally well with the extensions as taught by D1 and B1, which note extending the raised nose transition region into the vane passage to improve flow and reduce turbulence and shock losses. Therefore, it would have been an obvious matter of design choice to modify the extending curvature transition region of D1 and B1, to obtain the three quarters distance as specified in claim 3.
In Re Claim 4:
D1 as modified by M1 in claim 1 teaches:
The centrifugal slurry pump of claim 1, wherein the raised portion (which the region to adjust from nose height to final shroud height) extends from the inner region adjacent the leading edge of the plurality of pumping vanes.
D1 as modified by M1 in claim 1 does not teach:
The raised portion extends and ends about midway along the length of the passageway.
Examiner notes:
The instant Application is silent as to any specific advantage for the raised portion extending to about midway along the length of the passage. Further in so far as this claim is definite the office notes it no so clear as to how close to midway is required to be about midway.
B1 teaches:
A modification for slurry pump raised regions. [Page 1, ¶4.] The nose region that extends along blade length and sides as a raised portion(Fig. 1, I nose) by using larger nose radius of curvature (Inr and Fr). In particular the radius of curvature of the transition Fr, which begins at the blade leading edge, which extends from the nose to the outer diameter of the impeller can be for example from 0.2 to 0.75, or 0.2 to 0.52, or 0.33, or 0.22, or 0.1. Thus, the radius of curvature would result in a nose raised region transition extending to ¾ of the impeller or about half of the impeller radius since the distance of 0.75 of the diameter is larger than the diameter of just the length of the passages. [Page 2, ¶18-25.] This has the advantage of improving smooth flow patterns, minimizing shock losses at the entrances to the passages, and control the amount of turbulence as long as possible through the passageway by extending the raised region into it. [Page 4, ¶65-67.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the nose transition curvature region of D1(28, 29) to extend further into the blade passage by enlarging the radius of transition curvature as taught by B1, with the expectation of successfully improving the smooth flow patterns, minimizing shock loses at the entrances to the passages, and control the amount of turbulence as long as possible through the passageway by extending the raised region into it. [Page 4, ¶65-67.] This would yield the transition regions (29) of D1 extending further into the blade region.
Before the effective filing date of the invention, it would have been an obvious matter of design choice to a person of ordinary skill in the art to increase the raised region of D1 as modified by B1, to about three quarters the length of the vane passage, because Applicant has not specifically disclosed that the distance of three quarters of the passage extension of the raised region provides an advantage, is used for a particular purpose, or solves a stated problem over the normal raised region extension. One of ordinary skill in the art, furthermore, would have expected Applicant’s invention to perform equally well with the extensions as taught by D1 and B1, which note extending the raised nose transition region into the vane passage to improve flow and reduce turbulence and shock losses. Therefore, it would have been an obvious matter of design choice to modify the extending curvature transition region of D1 and B1, to obtain the three quarters distance as specified in claim 3.
In Re Claim 11:
D1 as modified by M1 in claim 1 teaches:
The centrifugal slurry pump of claim 1, wherein there are raised portions on the inner face of the back shroud.
D1 as modified by M1 in claim 1 does not teach:
The Raised portions on the inner face of the front shroud.
B1 teaches:
A modification for slurry pump raised regions. [Page 1, ¶4.] That there are raised portions (Fig. 12, 55) extending between sets of vanes (42) and extend from the front shroud(51). The examiner notes, the inner shroud. These raised regions are discharge guide vanes that project from either face extending between blades. [Page 3, ¶46, and Claim 7.] Discharge guide vanes, are upraised (30-35% of the full vane height). Said vanes are beveled , extend into the passageways at least midway, and provide advantages in that improve pump performance to reduce the potential for high velocity vortex type flows to form at lower flow values, and reduce particles wear into the front and rear shrouds. [Page 5, ¶86-92.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of D1, such that there are raised portions extending from the front side as taught by B1 with the expectation of successfully reducing high velocity vortex type flows and lower flow values, reducing particle wear into the front and rear shrouds. [Page 5, ¶86-92.]
This would yield raised portions extending from the front side in passageways between vanes.
Claim(s) 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over D1 and M1 as applied to claim 1 above, and further in view of US 5,609,468 to Burgess (B2).
In Re Claim 8:
D1 as modified in claim 1 teaches:
The centrifugal slurry pump impeller according to claim 2, wherein the distance between the inner faces of the back and front shroud is equal in the outer region and the inner region of the passageway. [See D1, Fig. 4.]
D1 as modified in claim 1 does not teach:
Wherein the distance between front and back shrouds is greater in the outer region than the inner region.
B2 teaches:
A centrifugal pump (Fig. 1) for slurry materials, (Col. 2, ll. 1-2) which has a wider outer region than the inner region (which is shortened by a nose, and contracts to a WIP before expanding). [This shape can be seen in Fig. 1.] The control of the vane passage width (Wip) allows setting it to a seal chamber width and control vane passage shapes to produce optimum pump impeller performance, without consuming too much power, and ease manufacture. [Col.2, line 39 – Col. 3, line 7.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the outlet and inlet and vane passage heights of D1, to match those as taught by B2, with the expectation of successfully providing improved pump impeller performance, without consuming too much power, and ease manufacture. [Col.2, line 39 – Col. 3, line 7.] This would yield the limitation the distance between front and back shrouds being greater in the outer region than the inner region.
Claim(s) 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over D1 and M1 as applied to claim 1 above, and further in view of EP 1,357,294 to Anderson (A1).
In Re Claim 15:
D1 as modified in claim 1 teaches:
A centrifugal slurry pump impeller according to claim 1, wherein there are pumping vanes. [See rejection of claim 1]
D1 as modified in claim 1, is silent as to:
The blades being backward swept.
A1 teaches:
A rotary pump for sewage water with solids, i.e. slurry, [Col. 1, ¶1-5.] It is noted that backswept blades can improve the performance of slurry pumps with its transport pollutants outward. The backswept can direct pollutants to more desirable locations to be swallowed by useful grooves, improving operation. [Col. 2, ¶15, Col. 3, ¶19, Col. 4, ¶26, claim 1.]
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of D1, to utilize backswept blades and pollutant receiving regions in the slurry pump as taught by A1, with the expectation directing pollutants/solids to more desirable handling locations in the system. [Col. 2, ¶15, Col. 3, ¶19, Col. 4, ¶26, claim 1.] This would yield backswept blades.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. US D 285,111 to Hanson, teaches an impeller with upraised portions extending between passages (Fig. 3.]. US 4,732,541 to Hyll teaches upraised regions (Fig. 12, 44) that extend between blade regions of impellers.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JOSHUA R BEEBE whose telephone number is (571)272-9968. The examiner can normally be reached M-F 10-6.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nathaniel Wiehe can be reached at 571-272-8648. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JOSHUA R BEEBE/Examiner, Art Unit 3745
/NATHANIEL E WIEHE/Supervisory Patent Examiner, Art Unit 3745