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 .
Election/Restrictions
Claims 18-20 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 02/12/2026.
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 11-15 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 11 recites the limitation: “the main blade angle of one or more of the main blades at the outer diameter of the inducer is smaller than the main blade angle at the outer lateral surface of the hub corresponding to a same axial location.” This limitation is unclear. Firstly it is unclear if more than one main blades are being compared, how they can all have a main blade angle at a single axial location since these main blades do not appear to axially overlap. Secondly, it is unclear how the main blade angle at the outer lateral surface of the hub is compared to more than one main blade angles of multiple main blades. Finally, it is unclear if this rule holds true for the entire length of each main blade from the leading edge to the trailing edge or if it applies to only a specific axial location along each main blade.
For the purposes of examination this limitation will be interpreted as follows: “the main blade angle of each of the main blades at the outer diameter of the inducer is smaller than the main blade angle of the respective main blade at the outer lateral surface of the hub corresponding to a same axial location.”
Claims 12-15 are also rejected by virtue of their dependence on a rejected claim.
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) 1-17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee (US 7,455,497) in view of Ashihara et al. (herein Ashihara) (US 2006/0110245). Regarding Claim 1:In Figures 2-4, Lee discloses an inducer (100) for a cryogenic pump (pump and motor unit 10 for pumping pressurized cryogenic gas which would use the inducer 100, see column 4, lines 42-47), the inducer (100) comprising: a hub (110) having an outer lateral surface (surface to which blades 120 are attached, henceforth referred to as OLS) extending from a leading end (at 116) to a trailing end (at 160), the outer lateral surface (OLS) having a leading surface section (116) having a first cylindrical shape (cylindrical at 114, see Figure 2), an intermediate surface section (section between 116 and approximately close to the trailing ends of the blades as seen in Figures 3-4, henceforth referred to as ISS) having a frustoconical shape (as mentioned in column 5, lines 13-15, the hub increases in diameter between the leading ends of the blades to the trailing ends of the blades thereby forming a frustoconical shape), and a trailing surface section (130) having a second cylindrical shape (as seen in Figure 4); main blades (120a-120c) extending radially from the outer lateral surface of the hub toward an outer diameter of the inducer and extending circumferentially along a first helical path over the leading surface section, the intermediate surface section, and the trailing surface section (as seen in Figure 3 and explained in column 4, line 62 to column 5, line 13), the first helical path having a helix angle from the leading surface section to the trailing surface section defining a main blade angle of the main blades (as seen in Figures 3-4); and splitter blades (150a-150c) extending radially from the outer lateral surface of the hub toward the outer diameter of the inducer and extending circumferentially along a second helical path over at least the intermediate surface section and the trailing surface section of the outer lateral surface of the hub (as seen in Figures 3-4, splitter blades 150a-150c extend over a helical path over the intermediate and trailing surface sections), the second helical path having a helix angle from the leading surface section to the trailing surface section defining a splitter blade angle of the splitter blades (as seen in Figures 3-4), each of the splitter blades located between two of the main blades, respectively (as seen in Figure 3, 150a is between 120a and 120b wherein this arrangement also applies to the other splitter blades as mentioned in column 5, lines 27-29).Lee is silent regarding whether the helix angle of the first helical path is increasing from the leading surface section to the trailing surface section for the main blades and whether the helix angle of the second helical path is increasing from the leading surface section to the trailing surface section for the splitter blades.However, in paragraph [0003] Ashihara states: “A blade angle from the inlet (leading edge) to the outlet (trailing edge) of the tip of the inducer is designed to be constant or to increase stepwise, linearly, or quadratically in order to meet a head required for the inducer. The specific increasing helix angle of the blades in the inducer (3) is shown in Figure 6B from the leading edge (i.e., at inlet) to the trailing edge (i.e., at outlet). Furthermore, as mentioned in paragraph [0014] this rate of increase in the helix angle is designed to ensure that the load can be distributed entirely on the blade along the hub and the required head can be maintained. Hence, based on Ashihara’s teachings, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified Lee’s main blades and splitter blades to have an increasing helix angle from the leading surface section to the trailing surface section as taught by Ashihara, since doing so would ensure that the load would be distributed entirely on the blades along the hub and the required head could be maintained. Regarding Claims 2-3:Lee mentions the following in the abstract: “A hub increases in diameter over the axial extent of the helical blades, thereby resulting in a decreasing depth of the blades between the inlet and outlet of the inducer.” Furthermore, in column 3, lines 11-14, Lee states: “An outer diameter of each primary blade and each secondary blade is generally constant from a leading edge to a trailing edge of such primary and such secondary blades.” Hence, it can be seen that the diameter of the hub increases while the outer diameter of the inducer corresponding to the outer diameter of the blades remains constant. Lee is silent regarding whether a diameter of the trailing surface section of the hub is at least about 75% (or 78% per claim 3) of the outer diameter of the inducer.It would have been an obvious matter of design choice to change the diameter of the trailing section of the hub to be at least about 75% (or about 78% per claim 3) of the outer diameter of the inducer, since such a modification would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. In re Rose, 105 USPQ 237 (CCPA 1955).Regarding Claims 4-5:Lee is silent regarding whether a diameter of the leading surface section (116) of the hub is less than about 33% (or about 30% per claim 5) of the outer diameter of the inducer.It would have been an obvious matter of design choice to change the diameter of the leading section of the hub to be at least about 33% (or about 30% per claim 5) of the outer diameter of the inducer, since such a modification would have involved a mere change in the size of a component. A change in size is generally recognized as being within the level of ordinary skill in the art. In re Rose, 105 USPQ 237 (CCPA 1955).Regarding Claim 6:Lee as modified discloses the inducer (100), wherein each of the main blades (120a-120c) have a swept leading edge defined by a gradually increasing radial blade length over a sweep angle from a leading tip (122a-122c), located at the leading surface section (116) of the hub (see Figures 2-3), to a trailing end (126a-126c), located at the outer diameter of the inducer (as seen in Figure 3). Lee further discloses that these blades have a high twist angle (i.e., sweep angle) to aid in compressing the vapor (see column 5, lines 24-27 and 48-52). Hence, Lee establishes that this sweep angle (twist angle) is a result effective variable to achieve the predictable result of compressing the vapor. It would have been obvious to one having ordinary skill in the art, before the effective filing date of the claimed invention, to have changed the sweep angle to be at least 40 degrees (which would be a high twist angle), 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).Regarding Claim 7:Lee as modified discloses the inducer (100), wherein a leading edge (152a-152c) of each splitter blade (150a-150c) is positioned relatively closer to a circumferentially trailing main blade than a circumferentially leading main blade (as seen in Figure 3 for instance, the leading edge 152a of splitter blade 150a is closer to the trailing main blade 120a than the leading main blade 120b. This configuration would apply to the other splitter blades as well).Regarding Claim 8:Lee as modified discloses the inducer (100), wherein the leading surface section (116) of the hub is greater than 5% of an axial length of the inducer and the trailing surface section (130) of the hub is greater than 5% of the axial length of the inducer (as seen in Figure 3, the leading surface section 116 and the trailing surface section 130 are both substantially greater than 5% of the axial length of the inducer).It is also noted that the boundaries of the trailing surface section (130) can be adjusted since they are arbitrarily assigned such that its length can be arbitrarily assigned.Regarding Claim 9:Lee as modified discloses the inducer (100), wherein each of the main blades (120a-120c) and each of the splitter blades (150a-150c) comprise an arcuate outer lateral surface defining the outer diameter of the inducer (as seen in Figure 3, all the outer lateral surfaces of the blades are arcuate and define the outer diameter of the inducer).Regarding Claim 10:Lee as modified discloses the inducer (100), wherein the arcuate outer lateral surface of one or more of the main blades (120a-120c) has a wrap angle of about 180 degrees (as mentioned in column 5, lines 5-9: “As is perhaps best represented in FIGS. 2 and 3, each blade is identical to the other blades and extends circumferentially approximately 180° from the leading edge 122a-122c to the respective trailing edge 126a-126c.”).Regarding Claim 11:Lee is silent regarding whether the main blade angle of each of the main blades (120a-120c) at the outer diameter of the inducer is smaller than the main blade angle of the respective main blade at the outer lateral surface of the hub corresponding to a same axial location.However, in Figures 6A-6B, Ashihara discloses that the main blade angle of each of the main blades at the outer diameter of the inducer (main blade angle denoted as tip blade angle ß bt in Figure 6A) is smaller than the main blade angle of the respective main blade at the outer lateral surface of the hub (main blade angle denoted as hub blade angle ß bh in Figure 6B) corresponding to a same axial location (as seen in Figures 6A-6B, ß bh is greater than ß bt for all axial positions).Hence, based on Ashihara’s teachings, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified Lee’s main blades such that the main blade angle of each of the main blades at the outer diameter of the inducer would smaller than the main blade angle of the respective main blade at the outer lateral surface of the hub corresponding to a same axial location (as taught by Ashihara), since doing so would yield predictable results such as stable load distribution and enhanced flow through the inducer (since Ashihara teaches both these results based on these blade designs). Regarding Claim 12:Lee as modified by Ashihara is silent regarding the specific main blade angles.However, in Figure 6B Ashihara the main blade angle (main blade angle denoted as hub blade angle ß bh in Figure 6B) of one or more of the main blades at a leading edge location at the outer lateral surface of the hub is less than about 25 degrees (at the inlet i.e., the leading edge location, the main blade angle ß bh is less than about 25 degrees). Ashihara shows that this angle is a controllable result effective variable that yields the predictable results: (as mentioned in paragraph [0046]: “the blade loading can be distributed entirely on the blade along the hub, and a required head can be maintained.”). It would have been obvious to one having ordinary skill in the art, before the effective filing date of the claimed invention, to change the main blade angle of one or more of the main blades at a leading edge location at the outer lateral surface of the hub to be less than about 25 degrees, 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).Regarding Claim 13:Lee as modified by Ashihara is silent regarding the specific main blade angles.However, in Figure 6B Ashihara the main blade angle (main blade angle denoted as hub blade angle ß bh in Figure 6B) of one or more of the main blades at a trailing edge location at the outer lateral surface of the hub is greater than about 27 degrees (at the outlet i.e., the trailing edge location, the main blade angle ß bh is clearly greater than about 27 degrees). Ashihara shows that this angle is a controllable result effective variable that yields the predictable results: (as mentioned in paragraph [0046]: “the blade loading can be distributed entirely on the blade along the hub, and a required head can be maintained.”). It would have been obvious to one having ordinary skill in the art, before the effective filing date of the claimed invention, to change the main blade angle of one or more of the main blades at a trailing edge location at the outer lateral surface of the hub to be greater than about 27 degrees, 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).Regarding Claim 14:Lee as modified by Ashihara is silent regarding whether the main blade angle of one or more of the main blades at the leading edge location at the outer diameter of the inducer is less than about 8.5 degrees.However, in Figure 6A Ashihara the main blade angle (main blade angle denoted as hub blade angle ß bt in Figure 6A) of one or more of the main blades at a leading edge location at the outer diameter of the inducer is less than about 8.5 degrees (at the inlet i.e., the leading edge location, the main blade angle ß bt is about 8.5 degrees as seen in Figure 6A). Ashihara shows that this angle is a controllable result effective variable that yields the predictable results: (as mentioned in paragraph [0046]: “the blade loading can be distributed entirely on the blade along the hub, and a required head can be maintained.”). It would have been obvious to one having ordinary skill in the art, before the effective filing date of the claimed invention, to change the main blade angle of one or more of the main blades at the leading edge location at the outer diameter of the inducer to be less than about 8.5 degrees, 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).Regarding Claim 15:Lee as modified by Ashihara is silent regarding whether the main blade angle of one or more of the main blades at the trailing edge location at the outer diameter of the inducer is greater than about 20 degrees.However, in Figure 6A Ashihara the main blade angle (main blade angle denoted as hub blade angle ß bt in Figure 6A) of one or more of the main blades at a trailing edge location at the outer diameter of the inducer is greater than about 20 degrees (at the outlet i.e., the trailing edge location, the main blade angle ß bt is about 8.5 degrees as seen in Figure 6A). Ashihara shows that this angle is a controllable result effective variable that yields the predictable results: (as mentioned in paragraph [0046]: “the blade loading can be distributed entirely on the blade along the hub, and a required head can be maintained.”). It would have been obvious to one having ordinary skill in the art, before the effective filing date of the claimed invention, to change the main blade angle of one or more of the main blades at the trailing edge location at the outer diameter of the inducer to be greater than about 20 degrees, 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).Regarding Claim 16:In Figures 14, Lee discloses a pump for pumping a cryogenic fluid (pump and motor unit 10 for pumping pressurized cryogenic gas which would use the inducer 100, see column 4, lines 42-47), the pump comprising: a fluid inlet (34) and a fluid outlet (see column 4, lines 39-41); a motor (12); a pump stage (two-stage pump 26 with pump stage 24); an inducer (100, shown as 20 in Figure 1) located between the fluid inlet and the pump stage (as seen in Figure 1), the inducer (100) comprising: a hub (110) having an outer lateral surface (surface to which blades 120 are attached, henceforth referred to as OLS) extending from a leading end (at 116) to a trailing end (at 160), the outer lateral surface (OLS) having a leading surface section (116) having a first cylindrical shape (cylindrical at 114, see Figure 2), an intermediate surface section (section between 116 and approximately close to the trailing ends of the blades as seen in Figures 3-4, henceforth referred to as ISS) having a frustoconical shape (as mentioned in column 5, lines 13-15, the hub increases in diameter between the leading ends of the blades to the trailing ends of the blades thereby forming a frustoconical shape), and a trailing surface section (130) having a second cylindrical shape (as seen in Figure 4); main blades (120a-120c) extending radially from the outer lateral surface of the hub toward an outer diameter of the inducer and extending circumferentially along a first helical path over the leading surface section, the intermediate surface section, and the trailing surface section (as seen in Figure 3 and explained in column 4, line 62 to column 5, line 13), the first helical path having a helix angle from the leading surface section to the trailing surface section (as seen in Figures 3-4); and splitter blades (150a-150c) extending radially from the outer lateral surface of the hub toward the outer diameter of the inducer and extending circumferentially along a second helical path from the intermediate surface section to the trailing surface section of the outer lateral surface of the hub (as seen in Figures 3-4, splitter blades 150a-150c extend over a helical path over the intermediate and trailing surface sections), the second helical path having a helix angle from the leading surface section to the trailing surface section (as seen in Figures 3-4), and a drive shaft (14) coupling the motor (12) to the pump stage (26) and the inducer (as seen in Figure 1, 15 couples 12 to 26 and 20 which would be replaced by 100).Lee is silent regarding whether the helix angle of the first helical path is increasing from the leading surface section to the trailing surface section for the main blades and whether the helix angle of the second helical path is increasing from the leading surface section to the trailing surface section for the splitter blades.However, in paragraph [0003] Ashihara states: “A blade angle from the inlet (leading edge) to the outlet (trailing edge) of the tip of the inducer is designed to be constant or to increase stepwise, linearly, or quadratically in order to meet a head required for the inducer. The specific increasing helix angle of the blades in the inducer (3) is shown in Figure 6B from the leading edge (i.e., at inlet) to the trailing edge (i.e., at outlet). Furthermore, as mentioned in paragraph [0014] this rate of increase in the helix angle is designed to ensure that the load can be distributed entirely on the blade along the hub and the required head can be maintained. Hence, based on Ashihara’s teachings, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have modified Lee’s main blades and splitter blades to have an increasing helix angle from the leading surface section to the trailing surface section as taught by Ashihara, since doing so would ensure that the load would be distributed entirely on the blades along the hub and the required head could be maintained. Regarding Claim 17:Lee as modified by Ashihara further comprising an inducer guide vane (52) located between the inducer and the pump stage (as mentioned in column 4, lines 29-34: “Vanes 52 extend radially across the annular passageway 44 at circumferentially spaced intervals and are effective to convert the velocity head from the impeller vanes 50 to a pressure head. The annular passageway 44 discharges beyond the vanes 52 into a flow passage 54 converging to the inlet end of the secondary impeller 24.” As seen in Figure 1, this guide vane 52 is located between the inducer 100 and the pump stage 24).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. See appended PTO-892 for relevant prior art related to inducers, blade arrangements and other pump structures.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DOMINICK L PLAKKOOTTAM whose telephone number is (571)270-7571. The examiner can normally be reached Monday - Friday 12 pm -8 pm ET.
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/DOMINICK L PLAKKOOTTAM/Primary Examiner, Art Unit 3746