DETAILED ACTION
Claim Interpretation
In claim 1, “the uncured resin applied to form the prepreg fibers using an immersion impregnation processes” [sic] is product-by-process language referring to a process of immersing the prepreg fibers in the uncured resin, e.g., by dip impregnation. See ¶[0045] of the published specification.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 8-10, 12 & 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Jaensch (DE 3133811) in view of Kipple et al. (US 3,710,437) and Ferguson et al. (US 7,119,149).
Regarding claim 1, Jaensch teaches an electrical insulation system for an electric motor, the system comprising:
a conductor with wires 3 wound in a slot 2 of a stator lamination stack 1,
an encapsulation material surrounding the wires in the slot (i.e., foamable or swellable resin coating on fibers 12 which are placed in slots in spaces surrounding wires 3 and heated; p.4:26-30; p.5:28-31; Fig.3);
a carrier including prepreg fibers (coated threads) 12 arranged between neighboring wires 3 (p.4:23-26; p.5:22-31);
the encapsulation material including a cured resin (i.e., coated threads 12 comprise foamable, swellable or self-adhesive substances or synthetic resin; p.5:26-31) mechanically fixing individual wires 3 and prepreg fibers 12 apart from one another (i.e., implied from arrangement of wires 3 and prepreg fibers 12 in Fig.3 and because resin coating creates sufficient bonding of the coil through heat treatment; p.5:28-31);
wherein, before winding, the prepreg fibers 12 carry an uncured resin filled with volume-increasing particles (i.e., resin coating substances include foamable or swellable substance; p.5:26-28, substance is subject to further heat treatment to bond coil assembly, p.5:28-31; i.e., initially resin is not cured)…, “the uncured resin applied to form the prepreg fibers using immersion impregnation processes” 1 [sic] (insofar as the structure implied, Jaensch’s uncured resin coating comprising foamable or swellable resin reads on this product-by-process limitation, independent of “immersion impregnation processes” used to apply the resin; moreover, Jaensch teaches a spool of coated threads, rovings or tapes is impregnated with a hardenable impregnating resin that gels “while still in the impregnating bath”, p.6:5-10, thus further reading on the process); and
after winding, the uncured resin sets into the cured resin during a heating process melting the resin providing homogenous distribution of the encapsulation material throughout the slot, and causing the volume increasing particles to increase a volume of the resin (these features are all inherent to the foamable or swellable resin coating fibers 12 which are placed in slots and heated per p.5:28-31. Per MPEP 2114 (II), “[a] claim containing a “recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus” if the prior art apparatus teaches all the structural limitations of the claim. Ex parte Masham, 2 USPQ2d 1647 (Bd. Pat. App. & Inter. 1987)).
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Jaensch differs in that the uncured resin (e.g., the foamable, swellable or self-adhesive substances or synthetic resin coating, per p.5:28-31) in the fibers 12 (which is subsequently heated and cured) is not “in a B-stage”, does not have a filler, and during the subsequent heating and curing process does not increase in volume “by a factor of at least two.”
But, regarding the first & second differences, Kipple teaches a resinous material used for insulating winding wires 22, 24 of a slotted core comprising B-stage resin only partially cured or advanced to a B-stage so that the resin particles will fuse, flow together and form a bond (c.3:6-11). In particular, Kipple teaches a preferred thermosettable resin comprising DGEBA (Bisphenol A diglycidyl ether) epoxy resins with a silica filler (c.3:17-20).
Thus, it would have been obvious before the effective filing date to provide Jaensch’s uncured resin in the fibers in a B-stage and filled with a filler since Kipple teaches a B-stage resin with a filler would have allowed the resin particles to have fused, flowed together and formed a bond.
Regarding the third difference, Ferguson teaches a thermosettable, high expansion two-component structural foam based on epoxy resin that expands to about twice its original volume using volume-increasing particles in the form of expandable thermoplastic resin microspheres, e.g., EXPANCEL® microspheres, as the blowing agent (abstract; c.5:10-15; c.6:4-42). EXPANCEL® microspheres are the same microspheres disclosed by the specification, p.9. Ferguson’s epoxy resin contains a filler such as a hollow glass microsphere (c.1:21-41) or an organic or inorganic filler (c.10:12-28). The weight range of Ferguson’s expandable microspheres (i.e., combined high-temperature and low-temperature blowing agents) is from 1 to about 15 wt% (c.12:11-12). This encompasses the same range of 1-10 wt% for the volume-increasing particles disclosed in the specification p.9. Ferguson’s foam system fills hollow structural members as an alternative to metal reinforcement, enables designers to reduce weight of structural members while maintaining stiffness and structural strength and provides a cured material having exceptionally good compression strength and modulus essentially free of large voids (abstract; c.1:5-26).
Thus, it would have been obvious before the effective filing date to further modify Jaensch and Kipple and provide a resin increasing in volume by a factor of two without creating open pores since Ferguson’s foam system would have reduced weight while maintaining stiffness and structural strength and provided a cured material having exceptionally good compression strength and modulus essentially free of large voids.
Regarding claim 8, Ferguson’s volume-increasing particles comprise EXPANCEL® microspheres which are gas-filled.
Regarding claim 9, Ferguson teaches additives and optional components (c.10:12-28 & c.10:64-68).
Regarding claim 10, Kipple’s resin comprises an epoxy resin (c.3:17-20). Similarly, Ferguson’s foam comprises epoxy resin (abstract).
Regarding method claim 12, Jaensch teaches a method for producing an electrical insulation system for an electric motor, the method comprising:
winding wires 3 and pre-impregnated fibers (coated threads) 12 (threads coated with synthetic resin including foamable or swellable substance) into a slot of a laminated core of a stator 8 (p.5:22-28; claim 2; Fig.2), wherein the pre-impregnated fibers 12 are arranged between neighboring wires 3 (p.4:23-26; Fig.3);
wherein the pre-impregnated fibers 12 are loaded via an immersion impregnation process (i.e., a spool of coated threads, rovings or tapes is impregnated with a hardenable impregnating resin that gels “while still in the impregnating bath”; p.6:5-10) with an impregnating resin and particles configured to increase in volume during curing (i.e., resin coating substances include foamable or swellable substance; p.5:26-28)…;
wherein there is no dip impregnation of the wound stator core (the only immersion impregnation disclosed in Jaensch is for the spool of coated threads, rovings or tapes per p.6:5-10, not the wound stator core);
heating the laminated core (heat treatment to bond coil assembly, p.5:28-31) such that the particles in the impregnating resin expand with an increase in volume and thereby increase the volume of the not-yet-cured impregnating resin (inherent to foamable or swellable substance coated threads 12; p.5:26-31), melting the impregnating resin providing homogenous distribution of the impregnating resin throughout the slot (the fibers exhibit increased capillary effect, p.8:13, which suggests they homogenously distribute the resin), and thereby curing the impregnated winding wire carrier insulation (i.e., resin is impregnated and cured; p.5:33-35).
Jaensch differs in that the pre-impregnating fibers (threads) 12 comprising the foamable or swellable coating are not loaded in a “B-stage” with “one or more fillers” and do not comprise particles “mak[ing] up between 2% and 6% by weight of the impregnating resin before curing” such that the volume of the not yet cured impregnating resin is increased “by a factor of two without creating open pores” when heated.
But, regarding the first & second differences, Kipple teaches a resinous material used for insulating winding wires 22, 24 of a slotted core comprising B-stage resin only partially cured or advanced to a B-stage so that the resin particles will fuse, flow together and form a bond (c.3:6-11). In particular, Kipple teaches a preferred thermosettable resin comprising DGEBA (Bisphenol A diglycidyl ether) epoxy resins with a silica filler (c.3:17-20).
Thus, it would have been obvious before the effective filing date to modify Jaensch and load the pre-impregnating fibers comprising a foamable and swellable coating in a B-stage with one or more fillers since Kipple teaches a B-stage would have allowed the resin particles to have fused, flowed together and formed a bond.
Regarding the third & fourth differences, Ferguson teaches a thermosettable, high expansion two-component structural foam based on epoxy resin that expands to about twice its original volume using volume-increasing particles in the form of expandable thermoplastic resin microspheres, e.g., EXPANCEL® microspheres, as the blowing agent (abstract; c.5:10-15; c.6:4-42). EXPANCEL® microspheres are the same microspheres disclosed by the specification, p.9. The weight range of Ferguson’s expandable microspheres (i.e., combined high-temperature and low-temperature blowing agents) is from 1 to about 15 wt% (c.12:11-12). This encompasses the claimed range of between 2-6 wt% for the volume-increasing particles. Ferguson’s foam system fills hollow structural members as an alternative to metal reinforcement, enables designers to reduce weight of structural members while maintaining stiffness and structural strength and provides a cured material having exceptionally good compression strength and modulus essentially free of large voids (abstract; c.1:5-26).
Thus, it would have been obvious before the effective filing date to further modify Jaensch and Kipple and provide a resin comprising particles making up between 2% and 6% by weight of the impregnating resin before curing that increases the volume of the not yet cured impregnating resin by a factor of two without creating open pores since Ferguson’s foam system would have reduced weight while maintaining stiffness and structural strength and provided a cured material having exceptionally good compression strength and modulus essentially free of large voids.
Regarding claim 18, Ferguson’s volume-increasing particles comprise EXPANCEL® microspheres which are gas-filled.
Regarding claim 19, Ferguson teaches additives and optional components (c.10:12-28 & c.10:64-68).
Regarding claim 20, Kipple’s encapsulation comprises an epoxy resin (c.3:17-20). Similarly, Ferguson’s foam comprises epoxy resin (abstract).
Claims 4-6 & 14-16 are rejected under 35 U.S.C. 103 as being unpatentable over Jaensch, Kipple & Ferguson as applied to claims 1 & 12 above, further in view of Bruce et al. (US Pat.Pub.2014/0342165).
Jaensch, Kipple & Ferguson substantially teach the invention but do not further teach the one or more fillers comprise mica particles (claims 4 & 14), aluminum oxide particles (claim 5 & 15) or boron nitride particles (claims 6 & 16).
But, Bruce teaches an electrical apparatus nano-hybrid matrix encapsulation comprising a carrier medium including inorganic filler material such as refractory ceramic materials such as mica or alumina suspended therein, to increase thermal conductivity and resistance to mechanical breakdown (¶[0017]-¶[0018]). Bruce also teaches addition of fibers increases the mechanical strength of the resultant composition (¶[0019]). Finally, regarding boron nitride, although Bruce does not explicitly teach boron nitride, Bruce’s broad teaching of refractory ceramic particles (¶[0017]) implicitly includes species such as boron nitride, since boron nitride is a well-known refractory material. For instance, Rickborn et al. (US 4,686,116), c.3:32-44, lists boron nitride as a non-oxide ceramic refractory material.
Thus, it would have been obvious before the effective filing date to further modify the resin of Jaensch Kipple & Ferguson with fillers such as mica particles, aluminum oxide particles or boron nitride particles since Bruce teaches these filler materials would have increased thermal conductivity, resistance to mechanical breakdown and mechanical strength of the carrier medium.
Claims 1, 4, 8-10, 12, 14 & 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Jaensch in view of Walsh et al. (US 5,609,806) and Saito et al. (US 8,519,049).
As noted in the preceding grounds of rejection, Jaensch differs only in that the uncured resin (e.g., the foamable, swellable or self-adhesive substances or synthetic resin coating the fibers 12, per p.5:28-31) in the fibers 12 (which is subsequently heated and cured) is not “in a B-stage”, does not have a filler and the volume does not increase “by a factor of at least two” when heated.
But, regarding the first difference, Walsh teaches pre-impregnated reinforcing fiber (i.e., “prepreg”) in the B-stage which retains chemical reactive sites which provide improved bonding between the prepreg material and other resinous materials (c.2:24-29; c.13:27-36).
Thus, it would have been obvious before the effective filing date to provide Jaensch’s
pre-impregnated resin in a B-stage since Walsh teaches prepreg in the B-stage would have provided improved bonding between the prepreg material and other resinous materials.
Regarding the second & third differences, Saito teaches a curable resin composition usable as a potting material (c.6:23-30) comprising reactive organic polymers and thermally expandable hollow spheres as essential components (c.21:65-c.22:6). Saito’s curable resin composition comprises a filler for reinforcement (c.18:31; c.19:9-10). The curable composition contains 0.01 parts by weight or more to less than 20 parts by weight of the thermally expandable hollow spheres with respect to a total of 100 parts by weight of the reactive organic polymers (c.22:21-33; c.39:62-c.40:35). Further, the volume of Saito’s thermally expandable hollow spheres expands by virtue of heating “to be many times as large as that in an initial state” (c.22:7-17). For context regarding this statement, note that Saito c.23:38-44 incorporates by reference, among others, Melber et al. (US 4,722,943) as an example of the hollow spheres employed. Melber discloses microspheres which expand in diameter by a factor of 5 to 10 times (c.5:46-48), which corresponds to an increase in volume by a factor of 125 to 1000. Melber also teaches EXPANCEL® polyvinylidene chloride microspheres (c.4:61-68). Therefore, since Saito’s teaching that the curable composition contains 0.01-20 parts by weight of thermally expandable hollow spheres encompasses the range of 1-10% by weight described in the specification p.9, and since they comprise the same EXPANCEL® microspheres disclosed in the specification p.9 which furthermore expand in volume by a factor of 125 to 1000 per Melber, this implies Saito’s curable composition increases in volume by a factor of at least two. Saito’s curable composition provides improved weather resistance, durability, excellent sealing and fire resistance (c.3:32-44).
Thus, it would have been further obvious before the effective filing date to configure the resin of Jaensch and Walsh with a filler and to increase volume by a factor of two without creating open pores since Saito teaches a filler would have provide reinforcement to the curable resin and the thermally expandable hollow spheres, e.g., EXPANCEL microspheres, would have provided the curable resin composition with improved weather resistance, durability, excellent sealing and fire resistance.
Regarding claim 4, Saito’s filler comprises mica particles, e.g., mica (c.19:14).
Regarding claim 8, Saito’s thermo-expandable hollow spheres comprise a volatile substance which is in a gas state at a temperature lower than the softening point of the resin (c.22:7-11). Similarly, by way of reference to Melber, Saito teaches EXPANCEL® polyvinylidene chloride microspheres with an inclusion of iso-butane as the blowing agent (Melber c.4:61-68; c.5:16-21).
Regarding claim 9, Saito’s resin potting compound may include additives such as a curing catalyst, an adhesion imparting agent, a physical property adjuster, etc. (c.21:55-64).
Regarding claim 10, Saito’s resin potting compound composition comprises an epoxy group (abstract).
Regarding method claim 12, as noted in the preceding grounds of rejection Jaensch differs in that the pre-impregnating fibers (threads) 12 comprising the foamable or swellable coating are not loaded in a “B-stage”, do have “one or more fillers” and do not comprise particles “mak[ing] up between 2% and 6% by weight of the impregnating resin before curing” which “increase the volume of the not yet cured impregnating resin by a factor of two without creating open pores”.
But, regarding the first difference, Walsh teaches pre-impregnated reinforcing fiber (i.e., “prepreg”) in the B-stage which retains chemical reactive sites which provide improved bonding between the prepreg material and other resinous materials (c.2:24-29; c.13:27-36).
Thus, it would have been obvious before the effective filing date to provide Jaensch’s
pre--impregnated resin in a B-stage since Walsh teaches prepreg in the B-stage would have provided improved bonding between the prepreg material and other resinous materials.
Regarding the second & third differences, Saito teaches a curable resin composition usable as a potting material (c.6:23-30) comprising reactive organic polymers and thermally expandable hollow spheres as essential components (c.21:65-c.22:6). Saito’s curable resin composition comprises a filler for reinforcement (c.18:31; c.19:9-10). The curable composition contains 0.01 parts by weight or more to less than 20 parts by weight of the thermally expandable hollow spheres with respect to a total of 100 parts by weight of the reactive organic polymers (c.22:21-33; c.39:62-c.40:35). Further, the volume of Saito’s thermally expandable hollow spheres expands by virtue of heating “to be many times as large as that in an initial state” (c.22:7-17). For context regarding this statement, note that Saito c.23:38-44 incorporates by reference, among others, Melber et al. (US 4,722,943) as an example of the hollow spheres employed. Melber discloses microspheres which expand in diameter by a factor of 5 to 10 times (c.5:46-48), which corresponds to an increase in volume by a factor of 125 to 1000. Melber also teaches EXPANCEL® polyvinylidene chloride microspheres (c.4:61-68). Therefore, since Saito’s teaching that the curable composition contains 0.01-20 parts by weight of thermally expandable hollow spheres encompasses the range of 2-6% by weight, and since they comprise the same EXPANCEL® microspheres disclosed in the specification p.9 which furthermore expand in volume by a factor of 125 to 1000 per Melber, this implies Saito’s curable composition increases in volume by a factor of at least two. Saito’s curable composition provides improved weather resistance, durability, excellent sealing and fire resistance (c.3:32-44).
Thus, it would have been further obvious before the effective filing date to provide the resin of Jaensch and Walsh with fillers and particles making up between 2% and 6% by weight of the impregnating resin before curing that increase in volume by a factor of two without creating open pores since Saito teaches a filler would have provided reinforcement to the curable resin and the particles comprising thermally expandable hollow spheres, e.g., EXPANCEL microspheres, would have provided the curable resin composition with improved weather resistance, durability, excellent sealing and fire resistance.
Regarding claim 14, Saito’s filler comprises mica particles, e.g., mica (c.19:14).
Regarding claim 18, Saito’s thermo-expandable hollow spheres comprise a volatile substance which is in a gas state at a temperature lower than the softening point of the resin (c.22:7-11). Similarly, by way of reference to Melber, Saito teaches EXPANCEL® polyvinylidene chloride microspheres with an inclusion of iso-butane as the blowing agent (Melber c.4:61-68; c.5:16-21).
Regarding claim 19, Saito’s resin potting compound may include additives such as a curing catalyst, an adhesion imparting agent, a physical property adjuster, etc. (c.21:55-64).
Regarding claim 20, Saito’s resin potting compound composition comprises an epoxy group (abstract).
Claims 1, 4, 8, & 10 are rejected under 35 U.S.C. 103 as being unpatentable over Dedelmahr et al. (DE 10323099) in view of Anderton et al. (US Pat.Pub.2012/0169172) & Saito.
Regarding apparatus claim 1, Dedelmahr teaches an electrical insulation system, the system comprising:
a conductor (winding) 1 with wires (individual conductors) 2 (abstract; ¶[0023]- ¶[0024]);
an encapsulation material surrounding the wires 2 (i.e., resin of prepreg 4 flows in cavities of winding gaps 5 and fills them completely after heating; ¶[0030]);
a carrier (prepreg sheet carrier) 4 including prepreg fibers (e.g., felt or nonwoven; abstract; ¶[0025]; claim 2) arranged between neighboring wires 2;
the encapsulation material including a cured (B-stage) resin (resin of prepreg 4) mechanically fixing individual wires 2 and prepreg fibers (of carrier 4) apart from one another (inherent, since after heating and curing, all the winding gaps 5 are filled so that a material and positive connection between fibers of carrier/prepreg 4 and wire conductors 2 is provided; ¶[0031]; Fig.3),
wherein, before winding, the prepreg fibers (of carrier 4) carry an uncured resin in a B-stage (i.e., prepreg comprises resin initially in the B-stage; ¶[0027]; claim 3), “the uncured resin applied to form the prepreg fibers using immersion impregnation processes” 2 [sic] (insofar as the structure implied, Dedelmahr’s uncured (B-stage) resin coating comprising the prepreg felt or nonwoven fibers reads on this product-by-process limitation, independent of “immersion impregnation processes” used to apply the resin); and
after winding, the uncured (B-stage) resin sets into the cured (C-stage) resin during a heating process melting the B-stage resin providing homogenous distribution of the encapsulation material (inherent to prepreg 4 which becomes liquid and penetrates winding gaps 5 during heating; “[u]pon heating, B-stage resin of prepreg 4 [converts] into the liquid A state…[and] flows into the remaining cavities of the winding gaps 5 and fills them completely after the heating process. Finally, the resin becomes the prepre[g] 4 in the C-state, i.e., the fully cured state in which all joints of the resin are three-dimensionally cross-linked transferred. The resin has good adhesion in the C state”; abstract; ¶[0030]; Fig.4).
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Dedelmahr does not teach the winding 1 is wound “in a slot of a stator lamination stack” or that the cured B-stage resin prepreg is “filled with volume-increasing particles”, has a “filler”
whereby the heating process provides homogenous distribution of the encapsulation material “throughout the slot” and “causes the volume-increasing particles to increase a volume of the resin by a factor of at least two.”
But, regarding the first difference, Anderton teaches a method for manufacturing a stator bar of an electric machine (inclusive of electric motors) comprising wires 3 insulated with insulation between each other (not numbered; ¶[0019]; Figs.1-2) and wound together in a slot 11 of a laminated core 10 of a stator (¶[0003]; claim 1; Figs.3-4). Anderton thus provides stator windings of a stator of the electric machine (abstract; ¶[0002]; claim 1).
Thus, it would have been obvious before the effective filing date to wind Dedelmahr’s winding in a slot of a laminated core of a stator of an electric motor since Anderton teaches this would have provided stator windings of a stator of an electric machine.
Regarding the second & third differences, Saito teaches a curable resin composition usable as a potting material (c.6:23-30) comprising reactive organic polymers and thermally expandable hollow spheres as essential components (c.21:65-c.22:6). Saito’s curable resin composition comprises a filler for reinforcement (c.18:31; c.19:9-10). The curable composition contains 0.01 parts by weight or more to less than 20 parts by weight of the thermally expandable hollow spheres with respect to a total of 100 parts by weight of the reactive organic polymers (c.22:21-33; c.39:62-c.40:35). Further, the volume of Saito’s thermally expandable hollow spheres expands by virtue of heating “to be many times as large as that in an initial state” (c.22:7-17). For context regarding this statement, note that Saito c.23:38-44 incorporates by reference, among others, Melber et al. (US 4,722,943) as an example of the hollow spheres employed. Melber discloses microspheres which expand in diameter by a factor of 5 to 10 times (c.5:46-48), which corresponds to an increase in volume by a factor of 125 to 1000. Melber also teaches EXPANCEL® polyvinylidene chloride microspheres (c.4:61-68). Therefore, since Saito’s teaching that the curable composition contains 0.01-20 parts by weight of thermally expandable hollow spheres encompasses the range of 1-10% by weight described in the specification p.9, and since they comprise the same EXPANCEL® microspheres disclosed in the specification p.9 which furthermore expand in volume by a factor of 125 to 1000 per Melber, this implies Saito’s curable composition increases in volume by a factor of at least two. Saito’s curable composition provides improved weather resistance, durability, excellent sealing and fire resistance (c.3:32-44).
Thus, it would have been further obvious before the effective filing date to configure the resin of Dedelmahr and Anderton with a filler and to increase its volume by a factor of two without creating open pores since Saito teaches a filler would have provided reinforcement to the curable resin and the thermally expandable hollow spheres, e.g., EXPANCEL microspheres, would have provided the curable resin composition with improved weather resistance, durability, excellent sealing and fire resistance.
Regarding claim 4, Saito’s filler comprise mica particles, e.g., mica (c.19:14).
Regarding claim 8, Saito’s thermo-expandable hollow spheres comprise a volatile substance which is in a gas state at a temperature lower than the softening point of the resin (c.22:7-11). Similarly, by way of reference to Melber, Saito teaches EXPANCEL® polyvinylidene chloride microspheres with an inclusion of iso-butane as the blowing agent (Melber c.4:61-68; c.5:16-21).
Regarding claim 10, Dedelmahr teaches the resin comprises epoxy (¶[0011]). Similarly, Saito’s resin potting compound composition comprises an epoxy group (abstract).
Claims 12, 14 & 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over Dedelmahr et al. (DE 10323099) in view of Blum et al. (US 6,455,111), Anderton et al. (US Pat.Pub.2012/0169172) & Saito.
Regarding method claim 12, Dedelmahr teaches a method for producing an electrical insulation system, the method comprising:
winding wires 2 and pre-impregnated fibers (e.g., felt or nonwoven B-stage carrier/prepreg 4; ¶[0025]; claim 2) arranged between neighboring wires (Fig.3);
wherein the pre-impregnated fibers (of carrier/prepreg 4) are loaded…with an impregnating resin in a B-stage (¶[0025]; claim 2)…;
wherein there is no dip impregnation of the wound stator core (this is not taught or suggested); and
heating the laminated core, melting the B-stage impregnating resin providing homogeneous distribution of the impregnating resin (i.e., “[u]pon heating, B-stage resin of prepreg 4 [converts] into the liquid A state…[and] flows into the remaining cavities of the winding gaps 5 and fills them completely after the heating process. Finally, the resin becomes the prepre[g] 4 in the C-state, i.e., the fully cured state in which all joints of the resin are three-dimensionally cross-linked transferred. The resin has good adhesion in the C state”; ¶[0030]; Fig.4), thereby curing the impregnated winding wire carrier insulation” (i.e., B-stage resin is fully cured to C-state; ¶[0030]).
Dedelmahr teaches the pre-impregnated fibers (of carrier/prepreg 4) are impregnated with the liquid (B-stage) resin (¶[0025]) but does not teach they are loaded “via an immersion impregnation process” which is understood per ¶[0045] of applicant’s published specification to mean dip impregnation. 3 Further, Dedelmahr does not teach winding the wires and pre-impregnated fibers “into a slot of a laminated core of a stator [of an electric motor]” such that the laminated core is also heated (in the heating step), or that his B-stage resin has “one or more fillers” and is loaded with “particles configured to increase in volume during curing…[which] make up between 2% and 6% by weight of the impregnating resin before curing using an immersion impregnation process” and which “increase the volume of the not yet cured impregnating resin by a factor of two without creating open pores”.
But, regarding the first difference, Blum teaches dip impregnation is commonly used in electrical engineering to impregnate resin compositions in carrier materials, in particular in the B-stage, in order to obtain curable prepregs (c.1:17-29).
Thus, it would have been obvious before the effective filing date to use an immersion impregnation (i.e., dip) process to load the resin on Dedelmahr’s prepreg since Blum teaches dip impregnation is commonly used in electrical engineering to impregnate resin compositions in carrier materials, in particular in the B-stage, in order to obtain curable prepregs.
Regarding the second difference, Anderton teaches a method for manufacturing a stator bar of an electric machine (inclusive of electric motors) comprising wires 3 insulated with insulation between each other (not numbered; ¶[0019]; Figs.1-2) and wound together in a slot 11 of a laminated core 10 of a stator (¶[0003]; claim 1; Figs.3-4). Anderton thus provides stator windings of a stator of the electric machine (abstract; ¶[0002]; claim 1).
Thus, it would have been obvious before the effective filing date to wind the winding of Dedelmahr & Blum in a slot of a laminated core of a stator of an electric motor since Anderton teaches this would have provided stator windings of a stator of an electric machine.
Regarding the third & fourth differences, Saito teaches a curable resin composition usable as a potting material (c.6:23-30) comprising reactive organic polymers and thermally expandable hollow spheres as essential components (c.21:65-c.22:6). Saito’s curable resin composition comprises a filler for reinforcement (c.18:31; c.19:9-10). The curable composition contains 0.01 parts by weight or more to less than 20 parts by weight of the thermally expandable hollow spheres with respect to a total of 100 parts by weight of the reactive organic polymers (c.22:21-33; c.39:62-c.40:35). Further, the volume of Saito’s thermally expandable hollow spheres expands by virtue of heating “to be many times as large as that in an initial state” (c.22:7-17). For context regarding this statement, note that Saito c.23:38-44 incorporates by reference, among others, Melber et al. (US 4,722,943) as an example of the hollow spheres employed. Melber discloses microspheres which expand in diameter by a factor of 5 to 10 times (c.5:46-48), which corresponds to an increase in volume by a factor of 125 to 1000. Melber also teaches EXPANCEL® polyvinylidene chloride microspheres (c.4:61-68). Therefore, since Saito’s teaching that the curable composition contains 0.01-20 parts by weight of thermally expandable hollow spheres encompasses the range of 2-6% by weight, and since they comprise the same EXPANCEL® microspheres disclosed in the specification p.9 which furthermore expand in volume by a factor of 125 to 1000 per Melber, this implies Saito’s curable composition increases in volume by a factor of at least two. Saito’s curable composition provides improved weather resistance, durability, excellent sealing and fire resistance (c.3:32-44).
Thus, it would have been further obvious before the effective filing date to provide the B-stage resin of Dedelmahr, Blum & Anderton with one or more fillers and with particles making up between 2% and 6% by weight of the impregnating resin before curing that increase in volume by a factor of two without creating open pores since Saito teaches one or more fillers would have provided reinforcement to the curable resin and the thermally expandable hollow spheres, e.g., EXPANCEL microspheres, would have provided the curable resin composition with improved weather resistance, durability, excellent sealing and fire resistance.
Regarding claim 14, Saito teaches one or more mice particle fillers, e.g., mica (c.19:14).
Regarding claim 18, Saito’s thermo-expandable hollow spheres comprise a volatile substance which is in a gas state at a temperature lower than the softening point of the resin (c.22:7-11). Similarly, by way of reference to Melber, Saito teaches EXPANCEL® polyvinylidene chloride microspheres with an inclusion of iso-butane as the blowing agent (Melber c.4:61-68; c.5:16-21).
Regarding claim 19, Saito’s resin potting compound may include additives such as a curing catalyst, an adhesion imparting agent, a physical property adjuster, etc. (c.21:55-64).
Regarding claim 20, Dedelmahr teaches the resin comprises epoxy (¶[0011]). Similarly, Saito’s resin potting compound composition comprises an epoxy group (abstract).
Response to Arguments
Applicant’s arguments filed 23 March 2026 have been fully considered but they are not persuasive.
Regarding Jaensch, Applicant notes Jaensch teaches use of yarns or rovings between the wires to increase the capillary effect on the resin during immersion of the stator in the resin bath, and alleges that “if one is not using an immersion process for the stator, there is no reason to include the yarns or rovings of Jaensch”. Applicant argues Jaensch does not teach or suggest avoiding dip immersion of the stator or volume-increasing particles, and that use of fillers in Jaensch’s resin would reduce the effectiveness of the capillary effect (Response, p.8).
These arguments are not persuasive. Applicant provides no evidence for the assertion that there is no reason to include yarns or rovings if one does not use an immersion process. Moreover, Jaensch teaches the spool of coated threads, rovings or tapes is impregnated with a hardenable impregnating resin that gels “while still in the impregnating bath” (p.6:5-10), thus suggesting use of an immersion process. Applicant provides no evidence for the assertion that use of fillers would reduce effectiveness of the capillary effect. To the contrary, art such as Lehner et al. (US 6,037,043) suggest Applicant’s assertion is groundless. Lehner teaches filler materials in epoxy resins used to seal a gap between a substrate and a chip. Lehner notes that resins “filled in this way yield the inventive good flow properties in the underflowing of the chip by means of capillary action” (c.5:10-24).
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BURTON S MULLINS whose telephone number is (571)272-2029. The examiner can normally be reached 9-5. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tulsidas C 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.
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/BURTON S MULLINS/Primary Examiner, Art Unit 2834
1 Per MPEP 2113 (I), product-by-process claims are not limited to the manipulations of the recited steps, only the structure implied by the steps. "[E]ven though product-by-process claims are limited by and defined by the process,
determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process." In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
2 Per MPEP 2113 (I), product-by-process claims are not limited to the manipulations of the recited steps, only the structure implied by the steps. "[E]ven though product-by-process claims are limited by and defined by the process,
determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process." In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
3 See Office Action Section 1.
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