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 .
Specification
The disclosure is objected to because of the following informalities:
in paragraph [0042], “a third winding 325 and a fourth winding 325” should apparently read “a fourth winding 326”;
in paragraph [0046], “the third frame 324, and the fourth frame 324” should apparently read “the third frame 323”;
in paragraph [0065], “A magnetizing direction of the third magnet 9” should apparently read “the third magnet 10,” since reference numeral 9 designates the third driving unit;
in paragraph [0060], “the turbine loss” should apparently read “the eddy current loss”;
and in paragraph [0066], “a fourth magnet unit” should apparently read “a fourth driving unit.” 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 1-13 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 1 recites an axial direction of the rotor assembly and thereafter recites the axial direction of the rotor shaft (two occurrences). There is insufficient antecedent basis for “the axial direction of the rotor shaft” in the claim, and it is unclear whether the recited axial directions are the same direction. For purposes of examination, the axial direction of the rotor shaft is interpreted as coaxial with, and the same as, the axial direction of the rotor assembly, consistent with FIGS. 1-3 of the instant application.
Claims 2-13 are rejected for depending from claim 1 and thereby inheriting the indefiniteness thereof. See MPEP § 2173.05(g).
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 1 is rejected under 35 U.S.C. 103 as being unpatentable over LEE(US 2015/0077033 A1) in view of AOSHIMA(US 5,384,506).
Regarding claim 1, Lee teaches a stepper motor(stepping motor 1; ¶[0042], FIG. 1),
comprising: a housing(housing 10 comprising housing body 11 and housing cover 12; ¶[0043]-[0044], FIG. 1);
a stator assembly fixed to the housing(stator assembly 20 disposed inside housing body 11 and remaining stationary during rotor rotation; ¶[0045], [0050]-[0051], FIG. 2A);
and a rotor assembly supported in the housing and rotatably connected to the housing, the stator assembly being provided around the rotor assembly and spaced apart from the rotor assembly(rotor 50 rotatably disposed inside stator assembly 20 with opposite ends of rotation shaft 51 supported by the housing 10 via lower bearing 15 and upper bearing 14, the rotor freely rotatable within rotor holes 33, 43 of the stator assembly; ¶[0044], [0048], [0050], FIGS. 1, 2A);
wherein the stator assembly comprises at least a first driving unit and a second driving unit distributed along an axial direction of the rotor assembly, wherein the first driving unit and the second driving unit are spaced apart from the rotor assembly and fixed to the housing(upper stator 30 and lower stator 40 disposed one below the other along the shaft axis within housing body 11, each an electromagnet formed of a bobbin, yokes, and a wound coil, and each spaced from the rotor by its rotor hole 33, 43; ¶[0045]-[0047], [0050], FIG. 2A);
the rotor assembly comprises a rotor shaft, a first magnet and a second magnet fixedly sleeved on the rotor shaft, wherein the first magnet and the second magnet are spaced along the axial direction of the rotor shaft, and two ends of the rotor shaft are rotatably connected to the housing(rotation shaft 51 carrying an upper rotor 52 and a lower rotor 53, each formed of a permanent magnet, disposed coaxially with the shaft and spaced a predetermined distance apart from each other; a first end of shaft 51 rotatably supported by lower bearing 15 and a second end rotatably supported by upper bearing 14; ¶[0044], [0048]-[0050], FIGS. 1, 2A);
the first driving unit is provided around the first magnet, and the second driving unit is provided around the second magnet(upper rotor 52 rotates facing the pole pieces 31a, 32a within rotor hole 33 of upper stator 30, and lower rotor 53 rotates facing the pole pieces 41a, 42a within rotor hole 43 of lower stator 40; ¶[0050], FIG. 2A);
a magnetizing direction of the first magnet and a magnetizing direction of the second magnet are both perpendicular to the axial direction of the rotor shaft(each of upper rotor 52 and lower rotor 53 is magnetized such that a plurality of N-poles and S-poles is formed alternately, the pole directions extending radially of, and thus perpendicular to, the shaft axis; ¶[0049], FIG. 2B).
Lee does not explicitly teach the magnetizing direction of the first magnet and the magnetizing direction of the second magnet are perpendicular to each other.
However, in the analogous art of compact permanent magnet stepper motors, Aoshima teaches a magnetizing direction of a first magnet and a magnetizing direction of a second magnet perpendicular to each other(first rotor member 30 and second rotor member 31, each a permanent magnet whose magnetized portions are divided into n = 2 poles each extending over 180° in the circumferential direction, fixed to a common shaft 32 and each driven by its own stator 28, 29 energized by coils 25, 26; the phase difference in magnetization between the first and second rotor members is α = 180° − 180°/n, which for n = 2 is α = 90°, whereby the pole axes of the two magnets are perpendicular to each other; col. 14 – col. 15, FIGS. 22-27).
Lee and Aoshima are in the same field of miniature permanent magnet stepping motors and address the same problem of effecting stepwise rotation of a shaft carrying axially arranged permanent magnets by selectively energizing stator units associated with the respective magnets. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify Lee by configuring each of the upper rotor (first magnet) and the lower rotor (second magnet) as a two-pole permanent magnet in accordance with Aoshima’s n = 2 rotor members, with the magnetizing direction of the first magnet and the magnetizing direction of the second magnet perpendicular to each other (α = 90°), as taught by Aoshima. One would be motivated to set the two magnetizing directions 90° apart because Aoshima teaches that this phase difference between the two rotor members establishes the quadrature detent positions that permit the rotor to be advanced in defined angular steps by switching over the energization of the coils of the two stator units (col. 14 – col. 15), providing the predictable benefit of defined two-phase stepping operation of the two-unit motor. The proposed combination is no more than the application of a known two-magnet, 90°-offset rotor configuration to a known stepping motor having two axially distributed driving units, yielding predictable results. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007).
8. Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over LEE in view of AOSHIMA and further in view of KUDO(US 2004/0170423 A1).
Regarding claim 2/1, Lee in view of Aoshima teaches the stepper motor of claim 1.
Lee further teaches each driving unit comprising a wound coil and yokes having pole pieces facing the respective magnet (¶[0046]-[0047]), and teaches the lower stator 40 configured in the same way as the upper stator 30 (¶[0047]).
Lee in view of Aoshima does not explicitly teach wherein the first driving unit comprises a first iron core and a second iron core provided opposite to each other on opposite sides of the first magnet, a first frame and a second frame respectively fixed to the first iron core and/or the second iron core, and a first winding and a second winding respectively sleeved on the first frame and the second frame; wherein the first iron core and the second iron core are fixed to the housing; the first magnet is provided within an accommodating space jointly enclosed by the first iron core, the second iron core, the first winding, and the second winding, nor the second driving unit comprises a third iron core and a fourth iron core provided opposite to each other on opposite sides of the second magnet, a third frame and a fourth frame respectively fixed to the third iron core and/or the fourth iron core, and a third winding and a fourth winding sleeved on the third frame and the fourth frame; wherein the third iron core and the fourth iron core are fixed to the housing, and the second magnet is provided within an accommodating space jointly enclosed by the third iron core, the fourth iron core, the third winding, and the fourth winding
However, in the analogous art of electromagnetic actuating devices for driving a two-pole permanent magnet rotor, Kudo teaches a first iron core and a second iron core provided opposite to each other on opposite sides of the first magnet(yokes 8 and 9 of identical shape, yoke 9 arranged in a state turned over relative to yoke 8 on the opposite side of two-pole permanent magnet rotor 7, with each arc-shaped magnetic pole surface faced to the surface of the rotor; ¶[0032]-[0033], FIGS. 1, 3);
a first frame and a second frame respectively fixed to the first iron core and/or the second iron core, and a first winding and a second winding respectively sleeved on the first frame and the second frame(coils 10 and 11 wound on bobbins, with portions of yokes 8 and 9 inserted into the bobbins from both sides of the hollow parts of the bobbins, whereby each bobbin carrying its winding is fixed on its yoke; ¶[0033]);
wherein the first iron core and the second iron core are fixed to the housing(yokes 8 and 9 each engaged at two portions with shafts 1c standing on base plate 1 and secured by attachment plate 3 and screws 4; ¶[0033]-[0034]);
and the first magnet is provided within an accommodating space jointly enclosed by the first iron core, the second iron core, the first winding, and the second winding(rotor 7 accommodated centrally between the arc-shaped pole surfaces of yokes 8, 9 and the bobbin-wound coils 10, 11 arranged on either side thereof; ¶[0033], FIG. 3).
Kudo further teaches that a step motor may be used in place of the current control type motor of its embodiments (¶[0063]).
Lee, Aoshima, and Kudo are in the same field of compact electromagnetic drive units for two-pole permanent magnet rotors. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to construct each of the first and second driving units of Lee as modified by Aoshima with the opposed-yoke, bobbin-wound construction taught by Kudo — the first driving unit with first and second iron cores, frames, and windings about the first magnet, and, per Lee’s teaching that the second stator is configured in the same way as the first (¶[0047]), the second driving unit likewise with third and fourth iron cores, frames, and windings about the second magnet. One would be motivated to do so because Kudo teaches that the windings can be pre-wound on the bobbins and the yoke portions then inserted into the bobbins from both sides (¶[0033]), providing the predictable benefit of simplified winding and assembly of each driving unit, the coils being windable on the bobbins before attachment of the yokes, as compared with winding a coil on a bobbin captured between the interleaved sawtooth pole pieces of Lee’s construction (Lee, ¶[0046]). The combination applies a known drive-unit construction to each unit of a known two-unit stepper motor with predictable results. KSR, 550 U.S. at 416.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over LEE in view of AOSHIME and KUDO, and further in view of KAVANAUGH(US 4,754,178).
Regarding claim 13/2, Lee in view of Aoshima and Kudo teaches the stepper motor of claim 2.
Lee in view of Aoshima and Kudo does not explicitly teach wherein the first iron core, the second iron core, the third iron core, and the fourth iron core are each formed by stacking multiple layers of iron cores.
However, in the analogous art of two-phase permanent magnet stepper motors, Kavanaugh teaches iron cores each formed by stacking multiple layers of iron cores(stator assembly 44 comprising a plurality of sequentially stacked laminations 46; col. 3, ll. 59-62; FIGS. 6-7; the arms 52 and poles 50 of the laminations 46 having electrical windings of the two phases of wires 55, 57 wound therearound; col. 3, l. 66 – col. 4, l. 5), and expressly teaches that the stator laminations 46 are made from a thin electrical grade magnetic steel to minimize eddy current losses (col. 4, ll. 41-43).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form each of the first, second, third, and fourth iron cores of Lee in view of Aoshima and Kudo by stacking multiple layers of iron cores as taught by Kavanaugh. One would be motivated to do so in order to minimize eddy current losses in the cores of the driving units, the predictable benefit expressly identified by Kavanaugh for the stacked-lamination construction (col. 4, ll. 41-43).
Allowable Subject Matter
Claims 3-12 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims, and if amended to overcome the rejection under 35 U.S.C. 112(b) set forth in this Office action.
Regarding claims 3 and 4, the prior art of record does not teach or fairly suggest the additional outboard fifth through eighth frames and windings spaced apart from the first through fourth frames and fixed to the iron cores (claim 3), or the frames integrally structured with the respective iron cores (claim 4), in combination with the remaining limitations of claims 1 and 2: Lee and Aoshima each employ a single coil per driving unit and Kudo employs a single coil per yoke (claim 3), and Kudo’s bobbins are separate members receiving inserted yoke portions rather than being integral with the yokes (claim 4).
Regarding claims 5-8, the prior art of record does not teach or fairly suggest the first and second spacers sleeved on the rotor shaft and fixed to the outer ends of the magnets (claim 5), the third spacer sandwiched between the first and second magnets (claim 6), or the first magnetic spacer sleeved on the rotor assembly and sandwiched between the first and second driving units (claim 7, and claim 8 depending therefrom): none of Lee, Aoshima, and Kudo discloses any spacer member on the rotor shaft, whether at the outer ends of the magnets or between them, Lee disclosing only an open middle space 17 between the upper and lower rotors (¶[0052]) without a spacer member between the magnets or between the driving units.
Regarding claims 9-11, the prior art of record does not teach or fairly suggest the housing comprising first and second cover plates with the first driving unit fixed to the first cover plate and the second driving unit fixed to the second cover plate (claim 9), together with the first and second bearings having outer peripheral sides fixed in the respective cover plates (claim 10) and the bearing bodies having tabs whose outer peripheral sides are fixed in the respective cover plates (claim 11): Lee’s stators are received in the housing body 11 rather than fixed to respective cover plates, and Kudo’s single drive unit is mounted between a base plate and an attachment plate.
Regarding claim 12, the prior art of record does not teach or fairly suggest the iron cores recessed on mutually opposite sides to form countersunk holes spaced along the radial direction of the rotor shaft with the frames assembled within the countersunk holes.
Conclusion
The prior art made of record and not relied upon is considered pertinent to the applicant’s disclosure.
SATO(US 2002/0089249 A1) teaches a rotor for a permanent magnet motor formed of cylindrical unit permanent magnets, each having magnetic anisotropy in a single diametrical direction perpendicular to the cylinder axis, coaxially stacked with adjacent unit magnets rotationally displaced by 180° divided by the number of unit magnets (90° for two unit magnets) to uniformize the magnetic flux density distribution (¶[0016]-[0017], [0048]-[0050]).
OGIHARA (US 4,696,560) teaches a bidirectional two-phase camera shutter stepping motor having a permanent magnet rotor whose shaft is rotatably mounted to an upper plate and a lower plate, and two U-shaped stators having leg portions surrounded by exciting coils L1 and L2, with one step set at 90° (col. 2 – col. 3, FIG. 4).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MOHAMMED QURESHI whose telephone number is (571)-272-8310. The examiner can normally be reached on 8:30 AM - 6:00 PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tulsidas Patel can be reached on 571-272-2098. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pairdirect. uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free).
/MOHAMMED AHMED QURESHI/Examiner, Art Unit 2834
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