DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on April 1, 2026 has been entered.
Response to Amendment
The Amendment filed April 1, 2026 has been entered. Claims 1, 2, 4 – 7 and 9 – 19 are pending in the application with claims 3 and 8 being cancelled.
Claim Objections
Claims 1, 2, 4 – 7 and 9 – 19 are objected to because of the following informalities:
In each of claims 1 and 18, last line: “the hydraulic pressure chambers” should read --the at least one hydraulic pressure chamber
Claim 1, last line: “the hydraulic fluid” should read --
Claim 9: The status identifier “(Currently Amended)” should read --(Previously Presented)--.
Claim 9, lines 2-3: “hydraulic fluid into at least one hydraulic pressure chamber” should read --the hydraulic fluid into the at least one hydraulic pressure chamber--.
Claims 16 and 17: The status identifier “(Currently Amended)” should read --(Previously Presented)--.
Claim 18, line 24: “is screwable by an elongate tool” should read --is screwable by the elongate tool--.
Claim 18: The limitations “wherein the drive shaft coupling comprises a radially expandable and/or radially compressible fastening element being at least partly arranged between the radial outer surface of the pump drive shaft and the radial inner surface of the hollow motor drive shaft, wherein the fastening element defines at least one hydraulic pressure chamber arranged between the radial inner surface of the hollow motor drive shaft and the radial outer surface of the pump drive shaft, wherein the fastening element is expandable upon pressurizing the at least one hydraulic pressure chamber,” in lines 29-35 should be deleted because they are similar to the limitations recited in lines 16-28 of the claim.
Claim 19: The status identifier “(New)” should read --(Previously Presented)--.
Claims 2, 4 – 7 and 9 – 17 are objected to for being dependent on claim 1.
Claim 19 is objected to for being dependent on claim 18.
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 5, 6, 10 and 11 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 “the fastening element is axially slotted from one or both axial ends of the fastening element”. The originally filed specification (see ¶57 of pg. pub of the instant application) identifies this “axially slotted” feature (slots 99) specifically with the first embodiment (mechanical slotted sleeve 95), noting that the slots allow the sleeve to “radially expand when it is pushed axially downward”. However, independent claim 1 has been amended to require the fastening element of the second embodiment, which is a hydraulic structure. The specification describes (see ¶61 of pg. pub of the instant application) the hydraulic fastening element as a structure defining at least one “hydraulic pressure chamber” between an “outer sleeve wall” and an “inner sleeve wall”. Unlike the mechanical embodiment, the hydraulic fastening element achieves expansion through the radial bulging of these walls upon pressurization, rather than through axial translation of a slotted sleeve. Thus, claim 5 is indefinite for being inconsistent since it not clear as to how the claimed “slotted” feature is present or compatible in the claimed coupling operated on hydraulic principle.
Claim 10 recites the limitation “wherein the fastener is directly or indirectly coupled to the fastening element for selectively pushing the fastening element towards the first axial motor drive shaft end and pulling the fastening element towards the second axial motor drive shaft end”. The filed specification (see ¶58 of pg. pub of the instant application) clarifies that this axial movement of the fastening element itself is the mechanism for the mechanical embodiment, where the fastener (101) pushes the slotted sleeve (95) onto a tapered shaft to expand it. Independent claim 1, as amended, now requires a “piston element” to pressurize hydraulic fluid within the coupling. In this hydraulic embodiment, the specification teaches (see ¶61 of pg. pub of the instant application) that the fastener (101) is screwed into the fastening element to “press a piston element 125 downward”. Since claim 10 recites an axial “pushing and pulling” of the fastening element that is functionally inconsistent with the piston-driven, stationary hydraulic structure required by claim 1, claim 10 is indefinite.
Claim 11 recites the limitation “a releasing sleeve axially clasping a head of the fastener and being coupled to the fastening element by a form fit”. The originally filed specification (see ¶59 of pg. pub of the instant application) explicitly identifies the “releasing sleeve” (107) as a component of the first embodiment (mechanical/slotted sleeve coupling), where it is used to pull the fastening element (95) upward when the fastener is unscrewed. In contrast, amended claim 1 now mandatorily requires a “hydraulic pressure chamber” and a “piston element”. According to the filed specification’s description (see ¶60 of pg. pub of the instant application) of the second embodiment (hydraulic), the piston element (125) is what pressurized the fluid within the chambers. This embodiment does not include – nor does it structurally provide for – the “releasing sleeve” described in the mechanical version. By reciting a feature that is physically and functionally associated with a mutually exclusive embodiment from the one now required by the independent claim 1, claim 11 is indefinite for being inconsistent since it not clear as to how the “releasing sleeve” is present in the claimed coupling operated on hydraulic principle.
Claim 6 is rejected for being dependent on claim 5.
Claim 11 is rejected for being dependent on claim 10.
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, 5 – 7, 9 – 15, 18 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Li, Long (CN 209671223U – herein after Li) in view of Peterson et al. (US 4,341,484 – herein after Peterson).
In reference to claim 1, Li teaches a pump assembly (see fig. 1) comprising:
an electric drive motor (3) comprising at least a motor drive shaft (21, see fig. 3) and a rotor (9 or 7+9, see figs. 1 and 3), wherein the motor drive shaft extends along a rotor axis (rotor axis being in ↨ direction in view of fig. 1/3) and the rotor is mechanically coupled to the motor drive shaft (inherent feature); and
a pump housing (as seen in fig. 1) enclosing an impeller (12) that is mechanically coupled to a pump drive shaft (13, see fig. 3),
wherein the pump drive shaft extends along the rotor axis (in ↨ direction in view of fig. 1/3),
wherein the motor drive shaft (21) is releasably coupled to the pump drive shaft (13) [the disclosure in ¶32 of translation does not disclose any permanent means to join both the shafts] for transferring torque from the motor drive shaft to the pump drive shaft (transfer of torque being an inherent feature),
wherein the motor drive shaft (21) is hollow (as seen in fig. 1/3) from a first axial motor drive shaft end (bottom end in view of fig. 1/3) to a second axial motor drive shaft end (top end in view of fig. 1/3) and defines a plurality of freely selectable drive shaft coupling axial positions (positions along the axial length of the hole within the motor drive shaft 21 that receives the pump drive shaft 13; for instance, the embodiment shown in fig. 1 shows the pump drive shaft having a first length such that its top end defines a first position for receiving a drive shaft coupling; however, for instance, if the pump drive shaft having a second length less than the first length is provided, then it defines a second position for receiving the drive shaft coupling; thus, the motor drive shaft defines “a plurality of freely selectable drive shaft coupling axial position”), extending along an axial length (in ↨ direction in view of fig. 1) between the first axial motor drive shaft end (bottom end) and the second axial motor drive shaft end (top end) and the motor drive shaft (21) is configured for different lengths of pump drive shafts to be coupled to the motor drive shaft at one of the drive shaft coupling axial positions along the axial length without changing the motor drive shaft (the motor drive shaft in Li is capable of having the claimed feature; it is to be noted while Li illustrates one specific insertion depth, the structure is inherently capable of receiving a shorter pump shaft at a different axial depth; the “freely selectable” nature of the position is defined by the existing physical depth of the hole),
wherein the pump drive shaft (13) protrudes into the hollow motor drive shaft at the first axial motor drive shaft end (as evident from fig. 3).
Li remains silent on the pump assembly wherein the motor drive shaft is releasably coupled to the pump drive shaft “by a drive shaft coupling” for transferring torque from the motor drive shaft to the pump drive shaft; “wherein the drive shaft coupling is arranged at least partly within the hollow motor drive shaft for transferring torque from the motor drive shaft to the pump drive shaft by frictional connection with a radial inner surface of the hollow motor drive shaft and/or a radial outer surface of the pump drive shaft”; “wherein the drive shaft coupling is accessible by an elongate tool through the second axial hollow motor drive shaft drive end for selectively tightening and releasing the drive shaft coupling”; “wherein the drive shaft coupling comprises a radially expandable and/or radially compressible fastening element being at least partly arranged between the radial outer surface of the pump drive shaft and the radial inner surface of the hollow motor drive shaft”; and “wherein the fastening element defines at least one hydraulic pressure chamber arranged between the radial inner surface of the hollow motor drive shaft and the radial outer surface of the pump drive shaft, wherein the fastening element is expandable upon pressurizing the at least one hydraulic pressure chamber, wherein the fastening element is configured to press hydraulic fluid by means of a piston element into the at least one hydraulic pressure chamber”.
However, Peterson teaches a device for joining components together, comprising:
a motor drive shaft (5, see fig. 1; hub 5 being equivalent to claimed hollow motor shaft); and
a pump drive shaft (4, see fig. 1; shaft 4 being equivalent to claimed pump drive shaft),
wherein the motor drive shaft (5) is releasably coupled to the pump drive shaft (4) by a drive shaft coupling (1+2+6+7+9, see fig. 1) for transferring torque from the motor drive shaft to the pump drive shaft (inherent feature),
wherein the motor drive shaft (5) is hollow (as evident from fig. 1) from a first axial motor drive shaft end (right end in view of fig. 1) to a second axial motor drive shaft end (left end in view of fig. 1),
wherein the pump drive shaft (4) protrudes into the hollow motor drive shaft (5),
wherein the drive shaft coupling (1+2+6+7+9) is arranged at least partly (see fig. 1) within the hollow motor drive shaft (5) for transferring torque from the motor drive shaft to the pump drive shaft by frictional connection (inherent feature in this coupling in view of disclosure in col. 1, lines 48-68 and col. 2, lines 1-2) with a radial inner surface of the hollow motor drive shaft and/or a radial outer surface of the pump drive shaft,
wherein the drive shaft coupling (1+2+6+7+9) is accessible by an elongate tool (tool for tightening or loosening of screws 7) for selectively tightening and releasing the drive shaft coupling;
wherein the drive shaft coupling (1+2+6+7+9) comprises a radially expandable and/or radially compressible fastening element (element made up of components 1+2+6) being at least partly arranged between the radial outer surface of the pump drive shaft (4) and the radial inner surface of the hollow motor drive shaft (5);
wherein the fastening element (1+2+6) defines at least one hydraulic pressure chamber (chamber with pressure medium 3) arranged between the radial inner surface of the hollow motor drive shaft and the radial outer surface of the pump drive shaft,
wherein the fastening element is expandable upon pressurizing the at least one hydraulic pressure chamber (see col. 1, lines 48-68 and col. 2, lines 1-2), and
wherein the fastening element (1+2+6) is configured to press hydraulic fluid (3) by means of a piston element (9) into the at least one hydraulic pressure chamber.
Therefore, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to couple the motor shaft and pump shaft in the pump assembly of Li using a drive shaft coupling as taught by Peterson in order to ensure slipping between the shafts when overloading occurs, as recognized by Peterson (see col. 1, lines 24-28).
Thus, Li, as modified, teaches the pump assembly, wherein the drive shaft coupling (1+2+6+7+9; of Peterson) is accessible by an elongate tool (tool for tightening or loosening of screws 7) through the second axial hollow motor drive shaft drive end (top end of Li’s hollow motor shaft 21) for selectively tightening and releasing the drive shaft coupling (of Peterson).
In reference to claim 5, Li, as modified, teaches the pump assembly, wherein the fastening element (1+2+6; of Peterson) is axially slotted (see axially slotted holes in flange 8 for receiving screws 7 in Peterson’s fig. 1) from one or both axial ends of the fastening element.
In reference to claim 6, Li, as modified, teaches the pump assembly, wherein the fastening element (1+2+6; of Peterson) comprises n≥2 axial slots distributed in an n-fold rotational symmetry (two axially slotted recesses, arranged in circumferential direction, in flange 8 for receiving screws 7 are evident from Peterson’s fig. 1) with respect to the rotor axis (of Li).
In reference to claim 7, Li, as modified, teaches the pump assembly, wherein the drive shaft coupling (1+2+6+7+9; of Peterson) comprises an axially screwable fastener (7; see Peterson’s fig. 1) being directly or indirectly coupled to the fastening element (1+2+6; of Peterson) by a form fit and/or a thread (see fig. 1 of Peterson; thread(s) being present in flange 8), wherein the fastener (7; see Peterson’s fig. 1) is screwable by an elongate tool being inserted through the second axial hollow motor drive shaft drive end (top end) into the hollow motor drive shaft (of Li).
In reference to claim 9, Li, as modified, teaches the pump assembly, wherein the fastener (7; see Peterson’s fig. 1) is configured to directly or indirectly press the hydraulic fluid (3; see Peterson’s fig. 1) into the at least one hydraulic pressure chamber (chamber between 1 and 2 in which the hydraulic fluid is present; see Peterson’s fig. 1) upon being screwed for tightening the drive shaft coupling.
In reference to claim 10, Li, as modified, teaches the pump assembly, wherein the fastener (7; see Peterson’s fig. 1) is directly or indirectly coupled to the fastening element (1+2+6; of Peterson) for selectively pushing the fastening element (pushing Peterson’s component 6 when fastener 7 is tightened) towards the first axial motor drive shaft (towards the bottom end of Li’s motor shaft) end and pulling (in radial direction) the fastening element (pulling Peterson’s component 6 when fastener 7 is loosened) towards the second axial motor drive shaft end (towards the top end of Li’s motor shaft).
In reference to claim 11, Li, as modified, teaches the pump assembly, further comprising a releasing sleeve (6; see Peterson’s fig. 1) axially clasping a head of the fastener (7; see Peterson’s fig. 1) and being coupled to the fastening element (1+2+6; of Peterson) by a form fit (“form fit” = mechanical connected in a way that the relative movement is prevented).
In reference to claim 12, Li, as modified, teaches the pump assembly, wherein the electric drive motor (of Li) comprises a motor housing (3; of Li), wherein the motor housing comprises an access opening (opening that is closed by cover 18 in fig. 1 of Li) arranged coaxially with the rotor axis (rotor axis being in ↨ direction in view of Li’s fig. 1) for accessing the drive shaft coupling (of Peterson) by an elongate tool through the second axial motor drive shaft end (top end of the motor shaft).
In reference to claim 13, Li, as modified, teaches the pump assembly, wherein the pump drive shaft (of Li) and/or the motor drive shaft (of Li) comprises engaging surfaces for a form fit coupling with a tool applied to prevent rotation upon tightening or releasing the drive shaft coupling (see fig. A below: engaging surface labeled “e1” corresponds to Li’s motor shaft 8 and engaging surface labeled “e2” corresponds to Li’s pump shaft 13; both of these surfaces can be hold by a tool such as wrench to prevent rotation of the shafts while tightening set screw in the coupling of Peterson).
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Fig. A: Edited fig. 3 of Lin to show claim interpretation.
In reference to claim 14, Li, as modified, teaches the pump assembly, wherein the pump assembly is a dry runner centrifugal pump assembly (the modified pump assembly of Li is viewed as “dry runner” centrifugal assembly; the phrase “dry runner” implies that electric motor is protected from pumped fluid; this is achieved by use of mechanical seal 17 in Li). Further, the specific type of pump is immaterial to the invention being claimed as this type of mechanical connection between two rotating shafts is not exclusive to dry runner centrifugal pump assemblies.
In reference to claim 15, Li, as modified, teaches the pump assembly, further comprising a pump drive shaft seal element (mechanical seal 17; in fig. 1 of Li) for sealing the pump housing around the pump drive shaft (13; of Li), wherein the pump drive shaft seal (17; of Li) is arranged axially between the impeller (12; of Li) and the drive shaft coupling (of Peterson).
In reference to claim 18, Li teaches a pump assembly (see fig. 1) comprising:
an electric drive motor (3) comprising at least a motor drive shaft (21, see fig. 3) and a rotor (9 or 7+9, see figs. 1 and 3), wherein the motor drive shaft extends along a rotor axis (rotor axis being in ↨ direction in view of fig. 1/3) and the rotor is mechanically coupled to the motor drive shaft (inherent feature); and
a pump housing (as seen in fig. 1) enclosing an impeller (12) that is mechanically coupled to a pump drive shaft (13, see fig. 3),
wherein the pump drive shaft extends along the rotor axis (in ↨ direction in view of fig. 1/3),
wherein the motor drive shaft (21) is releasably coupled to the pump drive shaft (13) [the disclosure in ¶32 of translation does not disclose any permanent means to join both the shafts] for transferring torque from the motor drive shaft to the pump drive shaft (transfer of torque being an inherent feature),
wherein the motor drive shaft (21) is hollow (as seen in fig. 1/3) from a first axial motor drive shaft end (bottom end in view of fig. 1/3) to a second axial motor drive shaft end (top end in view of fig. 1/3),
wherein the pump drive shaft (13 protrudes into the hollow motor drive shaft at the first axial motor drive shaft end (as evident from fig. 3).
Li remains silent on the pump assembly wherein the motor drive shaft is releasably coupled to the pump drive shaft “by a drive shaft coupling” for transferring torque from the motor drive shaft to the pump drive shaft; “wherein the drive shaft coupling is arranged at least partly within the hollow motor drive shaft for transferring torque from the motor drive shaft to the pump drive shaft by frictional connection with a radial inner surface of the hollow motor drive shaft and/or a radial outer surface of the pump drive shaft”; “wherein the drive shaft coupling is accessible by an elongate tool through the second axial hollow motor drive shaft drive end for selectively tightening and releasing the drive shaft coupling”; “wherein the drive shaft coupling comprises a radially expandable and/or radially compressible fastening element being that is at least partly arranged between the radial outer surface of the pump drive shaft and the radial inner surface of the hollow motor drive shaft”; and “wherein the fastening element defines at least one hydraulic pressure chamber arranged between the radial inner surface of the hollow motor drive shaft and the radial outer surface of the pump drive shaft, wherein the fastening element is expandable upon pressurizing the at least one hydraulic pressure chamber, wherein the drive shaft coupling comprises an axially screwable fastener that is directly or indirectly coupled to the fastening element by a form fit and/or a thread, wherein the fastener is screwable by an elongate tool that is inserted through the second axial hollow motor drive shaft drive end into the hollow motor drive shaft, wherein the fastener is configured to directly or indirectly press hydraulic fluid into the at least one hydraulic pressure chamber upon being screwed for tightening the drive shaft coupling”; and “wherein the fastening element is configured to press the hydraulic fluid by means of a piston element into the at least one hydraulic pressure chamber”.
However, Peterson teaches a device for joining components together, comprising:
a motor drive shaft (5, see fig. 1; hub 5 being equivalent to claimed hollow motor shaft); and
a pump drive shaft (4, see fig. 1; shaft 4 being equivalent to claimed pump drive shaft),
wherein the motor drive shaft (5) is releasably coupled to the pump drive shaft (4) by a drive shaft coupling (1+2+6+7+9, see fig. 1) for transferring torque from the motor drive shaft to the pump drive shaft (inherent feature),
wherein the motor drive shaft (5) is hollow (as evident from fig. 1) from a first axial motor drive shaft end (right end in view of fig. 1) to a second axial motor drive shaft end (left end in view of fig. 1),
wherein the pump drive shaft (4) protrudes into the hollow motor drive shaft (5),
wherein the drive shaft coupling (1+2+6+7+9) is arranged at least partly (see fig. 1) within the hollow motor drive shaft (5) for transferring torque from the motor drive shaft to the pump drive shaft by frictional connection (inherent feature in this coupling in view of disclosure in col. 1, lines 48-68 and col. 2, lines 1-2) with a radial inner surface of the hollow motor drive shaft and/or a radial outer surface of the pump drive shaft,
wherein the drive shaft coupling (1+2+6+7+9) is accessible by an elongate tool (tool for tightening or loosening of screws 7) for selectively tightening and releasing the drive shaft coupling;
wherein the drive shaft coupling (1+2+6+7+9) comprises a radially expandable and/or radially compressible fastening element (element made up of components 1+2+6) that is at least partly arranged between the radial outer surface of the pump drive shaft (4) and the radial inner surface of the hollow motor drive shaft (5);
wherein the fastening element (1+2+6) defines at least one hydraulic pressure chamber (chamber with pressure medium 3) arranged between the radial inner surface of the hollow motor drive shaft and the radial outer surface of the pump drive shaft,
wherein the fastening element is expandable upon pressurizing the at least one hydraulic pressure chamber (see col. 1, lines 48-68 and col. 2, lines 1-2),
wherein the drive shaft coupling (1+2+6+7+9) comprises an axially screwable fastener (7) being directly or indirectly coupled to the fastening element (1+2+6) by a form fit and/or a thread (see fig. 1 of Peterson; thread(s) being present in flange 8),
wherein the fastener (7) is screwable by the elongate tool,
wherein the fastener (7) is configured to directly or indirectly press hydraulic fluid (3) into the at least one hydraulic pressure chamber upon being screwed for tightening the drive shaft coupling, and
wherein the fastening element (1+2+6) is configured to press the hydraulic fluid (3) by means of a piston element (9) into the at least one hydraulic pressure chamber.
Therefore, it would have been obvious to the person of ordinary skill in the art before the effective filing date of the invention to couple the motor shaft and pump shaft in the pump assembly of Li using a drive shaft coupling as taught by Peterson in order to ensure slipping between the shafts when overloading occurs, as recognized by Peterson (see col. 1, lines 24-28).
Thus, Li, as modified, teaches the pump assembly, wherein the drive shaft coupling (1+2+6+7+9; of Peterson) is screwable by an elongate tool (tool for tightening or loosening of screws 7) that is inserted through the second axial hollow motor drive shaft drive end (top end of Li’s hollow motor shaft 21) into the hollow motor drive shaft (of Li); and wherein the fastener (7; of Peterson) is screwable by the elongate tool being inserted through the second axial hollow motor drive shaft drive end (top end) into the hollow motor drive shaft (of Li).
In reference to claim 19, Li, as modified, teaches the pump assembly, wherein the hollow motor drive shaft (21; of Li) defines drive shaft coupling axial positions (positions along the axial length of the hole within the motor drive shaft 21 that receives the pump drive shaft 13; for instance, the embodiment shown in fig. 1 shows the pump drive shaft having a first length such that its top end defines a first position for receiving a drive shaft coupling; however, for instance, if the pump drive shaft having a second length less than the first length is provided, then it defines a second position for receiving the drive shaft coupling; thus, the motor drive shaft defines “drive shaft coupling axial position”), along an axial length between the first axial motor drive shaft end (bottom end) and the second axial motor drive shaft end (top end), wherein the pump drive shaft protrudes into the hollow motor drive shaft at the first axial motor driveshaft end (as evident from Li’s fig. 3) based on a length of the pump drive shaft so as to occupy one of the drive shaft coupling axial positions depending on the length of the pump drive shaft [while Li illustrates one specific insertion depth, the structure is inherently capable of receiving a shorter pump shaft at a different axial depth; the nature of the position is defined by the existing physical depth of the hole].
Claims 2 and 4 are rejected under 35 U.S.C. 103 as being unpatentable over Li in view of Peterson and further in view of Elektra Beckum AG (DE 9416348U1 – herein after Elektra).
Regarding claim 2,
Li, as modified, remains silent on the pump assembly, wherein the radial outer surface of the pump drive shaft and/or the radial inner surface of the hollow motor drive shaft have a frusto-conical shape.
However, Elektra teaches (see fig. 1/5) a drive shaft (6) coupled to a driven shaft (5) using a coupling (15), wherein a radial inner surface (17) of the drive shaft has a frusto-conical shape that mates with corresponding frusto-conical shaped radial outer surface (18) of the coupling.
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 radial inner surface of the hollow motor drive shaft and its corresponding mating outer surface of the coupling in the modified pump of Li to have a frusto-conical shape as taught by Elektra for the purpose of enhancing the frictional connection between the motor shaft and its corresponding coupling element, as recognized by Elektra (see ¶39 of translation).
Regarding claim 4,
Li, as modified, remains silent on the pump assembly, wherein the fastening element has a wedged shape corresponding to a frusto-conical shape of the radial outer surface of the pump drive shaft and/or to a frusto-conical shape of the radial inner surface of the hollow motor drive shaft.
However, Elektra teaches (see fig. 1/4) a drive shaft (6) coupled to a driven shaft (5) using a coupling (15+19), wherein the coupling comprises a fastening element (for instance, 15) and wherein the fastening element (15) has a wedged shape corresponding to a frusto-conical shape of a radial inner surface (17) of the drive shaft (6).
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 radial inner surface of the hollow motor drive shaft and its corresponding mating outer surface on the fastening element of the drive shaft coupling in the modified pump of Li to have a frusto-conical shape as taught by Elektra for the purpose of enhancing the frictional connection between the motor shaft and its corresponding coupling element, as recognized by Elektra (see ¶39 of translation).
Claims 16 and 17 are rejected under 35 U.S.C. 103 as being unpatentable over Li in view of Peterson and evidenced by Van Steenburg et al. (US 2019/0128267 – herein after Van).
Li, as modified, remains silent on the pump assembly, wherein the electric drive motor (of Li) is configured to run at speeds of at least 500 rpm, as in claim 16; and wherein the electric drive motor (of Li) is configured to run at speeds of at least 6000 rpm.
As evidenced by Van (see ¶6), “Presently in the industry, pumps are typically operated at the synchronous speeds of the AC induction motor that is driving the pump. The specific speed of those pumps depends on the number of poles in the AC induction motor, with those typically being 2, 4, 6, 8, 10 and 12 pole motors. The speeds for these number of pole motors, utilizing a 60 Hz electrical frequency, are 3600, 1800, 1200, 900, 720, and 600 RPM, respectively. The speed of the electrical induction motor is determined by the power supply frequency and the number of poles in the motor winding,…”. Thus, “speed” is a result effective variable since it is determined by power supply frequency and number of poles in the motor winding.
Thus, 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 electric drive motor configured “to run at speeds of at least 500 rpm or of at least 6000 rpm” in the modified pump assembly of Li since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Further, applicant places no criticality on the claimed speed values, indicating simply (see ¶26 of pg. pub of the instant application) “Optionally, the electric drive motor may be configured to run at speeds above 500 rpm, preferably above 6000 rpm”.
Response to Arguments
Applicant's arguments, filed April 1, 2026, with respect to Jin have been fully considered but they are moot. The new grounds of rejection do not rely upon this reference in view of change in scope to amended claim 1.
Applicant's arguments, filed April 1, 2026, with respect to “a plurality of freely selectable axial coupling positions” being inherent in Li have been fully considered but they are not found to be persuasive. Li explicitly describes the motor shaft (21) as having “hollow shaft sleeve structure” with an axial “through hole (20)”. The physical depth of this hollow bore inherently provides a continuous range of axial positions. The “freely selectable” nature of the coupling is a result of the frictional connection taught by Peterson (used in this Office action instead of previously relied upon reference of Jin), which relied on smooth radial surfaces rather than per-machined stops or holes. A person having ordinary skill in the art would understand that a frictional coupling can be tightened at any point along the axial length of the pump shaft (13) that resides within the hollow bore of the motor shaft (21). Therefore, the ability to accommodate different shaft lengths is an inherent capability of the combined structure of Li and Peterson.
Conclusion
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/CHIRAG JARIWALA/Examiner, Art Unit 3746
/BRYAN M LETTMAN/Primary Examiner, Art Unit 3746
Prosecution Insights