DETAILED ACTION
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 1-9, 13, 15 & 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Cherney (US 9,148,034) in view of Garety (US Pat.Pub.2023/0198320).
Regarding claim 1, Cherney teaches a stator 14 for an electrical machine, the stator comprising:
a stator yoke (i.e., stator 14 comprising laminations 24);
a plurality of stator teeth 40 extending radially inwards from the stator yoke, the stator teeth defining stator slots 42 for stator windings (coils) 22;
a plurality of auxiliary teeth (not numbered) extending radially inwards from the stator yoke into the stator slots, wherein at least some of the auxiliary teeth comprise cooling channels (flow apertures) 50/52 (Fig.2), and
a conduit (circumferential passageway 54 in input plate 44) arranged to carry coolant circumferentially around the stator, the conduit 54 including a plurality of ports (not numbered, entrance of cooling channels 50/52 to conduit) connected to the cooling channels 50/52 in the auxiliary teeth to introduce coolant into the cooling channels (i.e., circumferential passageway 54 links input aperture 46 to all cooling bores 52; c.3:54-56), the conduit comprising a cooling passage (Figs.1-2 & 5-6).
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Cherney does not further teach the conduit/cooling passage 54 is “in the stator yoke” and comprises “a U-shaped annular trough extending circumferentially around the outside of the stator yoke.”
But, Garety teaches a fluid cooled stator with a conduit/cooling passage (annulus groove) 28 in the stator yoke (i.e., on the outside of stator core 21) that comprises a U-shaped annular trough extending circumferentially around the outside of the stator yoke (¶[0022]-¶[0023]; Fig.3). Cooling fluid flowing in axial grooves from the first and second ends of the stator core is collected in the annulus groove 28 and flows around the circumference of the stator core in the groove, thus providing cooling of the stator (¶[0001]; ¶[0016]; ¶[0023]).
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It would have been obvious before the effective filing date to provide Cherney with a
conduit/cooling passage in the stator yoke and comprising a U-shaped annular trough extending circumferentially around the outside of the stator yoke since Garety teaches this would have provided cooling of the stator.
Regarding claim 2, Cherney’s stator windings comprise a plurality of pre-formed coils; each coil is arranged to be slid onto one of the stator teeth 40; 1 and each auxiliary tooth extends radially inwards from the stator yoke into a stator slot 42 between the coils of two adjacent stator teeth (Fig.2).
Regarding claim 3, Cherney’s auxiliary teeth have a width in a tangential direction which decreases with increasing distance into the stator slot from the stator yoke (Fig.2).
Regarding claim 4, each of Cherney’s auxiliary teeth substantially fills a gap between the stator windings 22 of two adjacent teeth (Fig.2).
Regarding claim 5, Cherney’s stator windings 22 comprise pre-formed coils 2 of rectangular wire (Fig.2).
Regarding claim 6, each of Cherney’s coils 22 comprises a plurality of turns of rectangular wire, and each turn comprises a single width of rectangular wire (Figs.1-2).
Regarding claim 7, Cherney’s auxiliary teeth are arranged to conduct heat from the stator windings 22 to the stator yoke (inherent; Fig.2).
Regarding claim 8, Cherney’s cooling channels 50/52 run axially through the auxiliary teeth (Fig.2).
Regarding claim 9, Cherney’s cooling channels 50/52 are arranged to convey a liquid coolant (abstract), as are Garety’s (abstract).
Regarding claim 13, Garety’s cooling passage (annulus groove) 28 is located at or towards the cent[er], axially, of the stator yoke (Fig.3).
Regarding claim 15, Garety’s stator comprises a plurality of stacked stator laminations 7, and the cooling passage (annulus groove) 28 is formed by providing a group of stator laminations with an outside diameter which is less than that of other stator laminations (Fig.3).
Regarding claim 17, in the combination, Garety’s cooling passage (annulus groove) 28 is arranged to carry coolant circumferentially around the stator yoke (Fig.3) and Cherney’s cooling channels 50/52 are arranged to carry coolant axially through the auxiliary teeth (Figs.5-6).
Regarding claim 18, in Cherney the stator comprises a plurality of stacked laminations 24 and the auxiliary teeth are formed from the same laminations as the stator yoke (Fig.2).
Regarding claim 19, the grounds of rejection are the same as for claim 1 above. It is noted Cherney additionally teaches a rotor 12 and a cooling circuit (Fig.5) arranged to circulate coolant through the cooling channels 50/52 in the auxiliary teeth.
Regarding method claim 20, the grounds of rejection is the same for corresponding apparatus claim 1 above since the method is inherent to the structure of the combination.
Claims 1-9, 13, 15 & 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Sadarangani et al. (EP 2136455) in view of Dlala et al. (US Pat.Pub.2018/0054094).
Regarding claim 1, Sadarangani teaches a stator 1 for an electrical machine, the stator comprising:
a stator yoke 2;
a plurality of stator teeth 4 extending radially inwards from the stator yoke, the stator teeth defining stator slots 8 for stator windings (coils) 6;
a plurality of auxiliary (intermediate) teeth 16 extending radially inwards from the stator yoke into the stator slots, wherein at least some of the auxiliary teeth comprise cooling channels (cooling duct) 20 (¶[0023]; Fig.4); and
a conduit arranged to carry coolant…into the cooling channels [20] in the auxiliary teeth [16] (i.e., cooling medium circulates in cooling ducts; ¶[0022]).
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Sadarangani does not further teach a conduit arranged to carry coolant “circumferentially around the stator, the conduit including a plurality of ports connected to cooling channels [20] in the auxiliary teeth [16] to introduce coolant into the cooling channels, the conduit comprising a cooling passage in the stator yoke, the cooling passage comprising a U-shaped annular trough extending circumferentially around the outside of the stator yoke.”
But, Dlala teaches a stator for an electrical machine, the stator comprising a plurality of stator teeth 103/1301 extending radially inwards from the stator yoke (Figs.1/13); wherein at least some of the teeth comprise cooling channels 1303; and a conduit (manifold) 1309 arranged to carry coolant circumferentially around the stator (i.e., coolant flows about the entire perimeter of manifold; ¶[0066]; Fig.13), the conduit including a plurality of ports (not numbered) connected to the cooling channels 1303 in the teeth to introduce coolant into the cooling channels (i.e., coolant is pumped through intake 1221 and into manifold 1309, the manifold then distributing the coolant to all of the axial cooling channels 1303; ¶[0066]), the conduit 1309 comprising a cooling passage 1309 in the stator yoke (i.e., between left and right stator portions 1305/1307; Fig.13), the cooling passage 1309 comprising a U-shaped annular trough extending circumferentially around the outside of the stator yoke (i.e., between left and right stator portions 1305/1307; Fig.13). Dlala’s conduit/manifold integrated into the stator between first and second stator portions distributes coolant to all of the axial cooling channels and couples the coolant passageways to a suitable coolant pump and heat sink to maintain the temperature of the motor within its specified operating range (¶[0004]; ¶[0011]; ¶[0066]).
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It would have been obvious before the effective filing date to provide Sadarangani with a conduit arranged to carry coolant circumferentially around the stator and into the cooling channels in the auxiliary teeth since Dlala teaches this would have enabled distribution of coolant to all of the axial cooling channels and coupling them to a suitable coolant pump and heat sink to maintain the temperature of the motor within its specified operating range.
Regarding claim 2, Sadarangani’s stator windings (coils) 6 comprise a plurality of pre-formed coils; each coil is arranged to be slid onto one of the stator teeth 4; 3 and each auxiliary tooth 16 extends radially inwards from the stator yoke 2 into a stator slot 8 between the coils of two adjacent stator teeth (Fig.4).
Regarding claim 3, Sadarangani’s auxiliary teeth 18 have a width in a tangential direction which decreases with increasing distance into the stator slot 8 from the stator yoke 2 (Fig.4).
Regarding claim 4, in Sadarangani each auxiliary tooth 18 substantially fills a gap between the stator windings 6 of two adjacent teeth (Fig.4).
Regarding claim 5, in Sadarangani the stator windings (coils) 6 comprise pre-formed coils 4 of rectangular wire (abstract; Fig.4).
Regarding claim 6, in Sadarangani each coil 6 comprises a plurality of turns of rectangular wire, and each turn comprises a single width of rectangular wire (abstract; Fig.4).
Regarding claim 7, in Sadarangani the auxiliary teeth 18 are arranged to conduct heat from the stator windings (coils) 6 to the stator yoke 2 (since intermediate teeth are one piece with yoke; ¶[0022]; Fig.4).
Regarding claim 8, in Sadarangani the cooling channels 20 run axially through the auxiliary teeth 18 (Fig.4).
Regarding claim 9, in Sadarangani the cooling channels 20 are arranged to convey a liquid coolant (¶[0023]). Bradfield’s channels also convey liquid coolant (c.4:3-15).
Regarding claim 13, Dlala’s cooling passages 201 are located at or towards the center, axially, of the stator yoke (Fig.2 embodiment).
Regarding claim 15, Dlala’s stator comprises a plurality of stacked stator laminations (lamination stack; abstract), and the cooling passage is formed by providing a group of stator laminations with an outside diameter which is less than that of other stator laminations (Figs.12-13).
Regarding claim 17, in the combination, Dlala’s cooling passage (conduit/manifold) 1309 is arranged to carry coolant circumferentially around the stator yoke (i.e., coolant flows about the entire perimeter of manifold; ¶[0066]; Fig.13) and Sadarangani’s cooling ducts 20 are arranged to carry coolant axially through the auxiliary teeth (Fig.4).
Regarding claim 18, Dlala teaches the stator comprising a plurality of stacked laminations (i.e, lamination stack; abstract) and Sadarangani teaches the auxiliary teeth 16 are formed from the same laminations as the stator yoke (¶[0022]).
Regarding claim 19, the grounds of rejection are the same as for claim 1 above. It is further noted Sadarangani’s electrical machine comprises a rotor (not numbered; abstract),
and a cooling circuit arranged to circulate coolant through…the cooling channels 20 in the auxiliary teeth 18 (i.e., cooling system circulates cooling medium through ducts; ¶[0023]).
Regarding method claim 20, the grounds of rejection is the same for corresponding apparatus claim 1 above since the method is inherent to the structure of the combination.
Claim 10 is rejected under 35 U.S.C. 103 as being unpatentable over Cherney & Garety or Sadarangani & Dlala as applied to claims 1, further in view of Adra (US Pat.Pub. 2006/0043801).
None of the combinations further teach the U-shaped annular trough comprises a pipe.
But, Adra teaches a liquid cooled electric machine comprising at least one annular pipe (inlet manifold) 70 (or outlet manifold 72) located outside of and axially adjacent to at least one end face of a stator yoke (stator) 38 (Fig.2); and a plurality of ports (not numbered, correspon-ding to tubes 74), each port having a first portion (not numbered) extending radially inwards from the annular pipe 70/72 toward a center of the stator yoke and a second portion (not numbered) extending axially from the first portion toward one of the cooling channels (formed by tubes 74; Figs.2&4). Adra’s annular pipe/inlet manifold 70 with plural ports directs the heat-transferring medium from cooling system 14 through tubes 74 and the outlet manifold 72 directs heat-transferring medium from the tubes 74 to the cooling system 14, to thereby remove heat from the windings and stator (¶[0027]).
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Thus, it would have been obvious before the effective filing date to provide the U-shaped annular trough of Cherney & Garety or Sadarangani & Dlala with at least one annular pipe since Adra teaches this would have been desirable to direct heat-transferring medium to and from a cooling system to the conduits to thereby remove heat from the windings and stator.
Claims 21-22 are rejected Cherney & Garety or Sadarangani & Dlala as applied to claims 1 and 19, further in view of Houle et al. (US 6,819,016).
None of Cherney & Garety or Sadarangani & Dlala further teach the U-shaped annular trough is “fitted with an annular pipe therein, the annular pipe comprising a port configured to receive the coolant and to flow the coolant through the cooling channels.”
But, Houle teaches a liquid cooling arrangement for a stator (embodiments include external stator; c.4:52-57) comprising C-shaped channels 104 in a heat storing element 102 and an annular pipe (cooling tube) 106 therein, the cooling tube comprising a port (inlet) 110 configured to receive the coolant and to flow the coolant through the cooling channels (abstract; c.4:8-40; Figs.6-9). Houle teaches that prior art machines using laminations provided with apertures allowing flow of cooling liquid risked failure caused by leaks should the seal between adjacent laminations fail, whereas use of pipes (tubes) inserted in channels prevents this and allows heat to be extracted (c.1:25-34; c.2:45-50).
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Thus, it would have been obvious to fit the U-shaped trough of Cherney & Garety or Sadarangani & Dlala with an annular pipe therein, the annular pipe comprising a port configured to receive the coolant and to flow the coolant through the cooling channels, since Houle teaches a pipe would have been desirable to extract heat and simultaneously prevent leaks should the seal between adjacent laminations fail.
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over Cherney & Garety or Sadarangani & Dlala, further in view of Adra.
As noted above in the respective rejections of claim 1, the combinations of Cherney & Garety and Sadarangani & Dlala each teach the claimed features except for “at least one annular pipe located outside of and axially adjacent to at least one end face of the stator yoke; and a plurality of ports, each port having a first portion extending radially inwards from the annular pipe toward a center of the stator yoke and a second portion extending axially from the first portion toward one of the cooling channels in the auxiliary teeth.”
But, Adra teaches a liquid cooled electric machine comprising at least one annular pipe (inlet manifold) 70 (or outlet manifold 72) located outside of and axially adjacent to at least one end face of a stator yoke (stator) 38 (Fig.2); and a plurality of ports (not numbered, corresponding to tubes 74), each port having a first portion (not numbered) extending radially inwards from the annular pipe 70/72 toward a center of the stator yoke and a second portion (not numbered) extending axially from the first portion toward one of the cooling channels (formed by tubes 74; Figs.2&4). Adra’s annular inlet manifold 70 with plural ports directs the heat-transferring medium from cooling system 14 through tubes 74 and the outlet manifold 72 directs heat-transferring medium from the tubes 74 to the cooling system 14, to thereby remove heat from the windings and stator (¶[0027]).
Thus, it would have been obvious before the effective filing date to provide Cherney & Garety or Sadarangani & Dlala with at least one annular pipe located outside of and axially adjacent to at least one end face of the stator yoke; and a plurality of ports, each port having a first portion extending radially inwards from the annular pipe toward a center of the stator yoke and a second portion extending axially from the first portion toward one of the cooling channels in the auxiliary teeth, since Adra teaches this would have been desirable to direct heat-transferring medium to and from a cooling system to the conduits to thereby remove heat from the windings and stator.
Response to Arguments
Applicant’s arguments made in the 05 May 2026 response with respect to independent claims 1, 19-20 & 23 have been considered but are not wholly persuasive.
Applicant argues neither Cherney nor Garety discloses “a plurality of ports connected to the cooling channels in the auxiliary teeth to introduce coolant into the cooling channels.” But, Cherney teaches the conduit (circumferential passageway 54 in input plate 44) includes a plurality of ports (not numbered, entrance of cooling channels 50/52 to conduit) connected to the cooling channels 50/52 in the auxiliary teeth to introduce coolant into the cooling channels (i.e., circumferential passageway 54 links input aperture 46 to all cooling bores 52; c.3:54-56), the conduit comprising a cooling passage (Figs.1-2 & 5-6). Regarding Garety’s lack of teaching of cooling channels within auxiliary teeth, these are disclosed in Cherney. Further, one cannot show non-obviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Regarding the argument that neither Garety nor Cherney disclose or teach a mechanism for introducing coolant from an outer periphery of a stator into cooling bores positioned within auxiliary teeth, it is noted that Cherney’s fluid input plate 44 introduces coolant from an outer periphery, i.e., “[a]s illustrated schematically in FIG.5, the cooling fluid travels from source tank S, into input aperture 46 of input plate 44 (via pump 71 and a filter), inward to portion 48, laterally through cooling tube 60 (where present) through lamination stack 20, out of output metering apertures 74, into distribution facets 72, along end windings of coil 22…” (c.4:26-32).
Regarding Sadarangani & Bradfield, Applicant argues neither teaches a conduit having “a plurality of ports connected to the cooling channels in the auxiliary teeth to introduce coolant into the cooling channels”. But, to the extent this applies to the new rejection over Sadarangani & Dlala, it is noted that Dlala’s conduit (manifold) 1309 includes a plurality of ports (not numbered) connected to the cooling channels 1303 in the teeth to introduce coolant into the cooling channels (i.e., coolant is pumped through intake 1221 and into manifold 1309, the manifold then distributing the coolant to all of the axial cooling channels 1303; ¶[0066]). Dlala’s conduit/manifold integrated into the stator between first and second stator portions distributes coolant to all of the axial cooling channels and couples the coolant passageways to a suitable coolant pump and heat sink to maintain the temperature of the motor within its specified operating range (¶[0004]; ¶[0011]; ¶[0066]).
Conclusion
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 at 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 These product-by-process features are not given patentable weight. 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 Ibid.
3 Ibid.
4 Ibid.
Prosecution Insights