PCT
`peT
`WORLD INTELLEcruAL PROPERTY ORGANIZATION
`WORLD INTELLECfUAL PROPERTY ORGANIZATION
`
`International Bureau International Bureau
`
`INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)
`WO 95/12912
`WO 95/12912
`(51) International Patent Classification 6 :
`(51) International Patent Classification 6 :
`H02K 1116, 3/46
`H02K 1116, 3/46
`
`(11) International Publication Number:
`(11) International Publication Number:
`
`
`
`( 43) International Publication Date: (43) International Publication Date:
`
`
`
`11 May 1995 (11.05.95) 11 May 1995 (11.05.95)
`
`
`
`(21) International Application Number: (21) International Application Number:
`
`
`
`PCT/SE94/0 1 026 PCT/SE9410 1 026
`
`
`
`(22) International Filing Date: (22) International Filing Date:
`
`
`
`1 November 1994 (01.11.94) 1 November 1994 (01.11.94)
`
`
`(30) Priority Data: (30) Priority Data:
`
`9303602-8 9303602-8
`
`9400076-7 9400076-7
`
`9401524-5 9401524-5
`
`1 November 1993 (01.11.93)
`1 November 1993 (01.11.93)
`10 January 1994 (10.01.94)
`10 January 1994 (10.01.94)
`3 May 1994 (03.05.94)
`3 May 1994 (03.05.94)
`
`
`SE SE
`
`SE SE
`
`SE SE
`
`
`(71) Applicant (for all designated States except US): STRIDSBERG (71) Applicant (for all designated States except US): STRIDSBERG
`
`INNOVATION AB [SE/SE]; Tanneforsv!lgen 14, S-122 47 INNOVATION AB [SElSE]; Tanneforsv!lgen 14, S-122 47
`
`Enskede (SE). Enskede (SE).
`
`
`(72) Inventor; and (72) Inventor; and
`
`(75) Inventor/Applicant (for US only): STRIDSBERG, Lennart (75) Inventor/Applicant (for US only): STRIDSBERG, Lennart
`[SE/SE]; Tanneforsvagen 14, S-122 47 Enskede (SE).
`[SElSE]; Tanneforsvagen 14, S-122 47 Enskede (SE).
`
`
`(74) Agents: LINDEN, Stefan et al.; Bergenstri!hle & Lindvall AB, (74) Agents: LINDEN, Stefan et a1.; Bergenstr1!hle & Lindvall AB,
`P. O. Box 17704, S-118 93 Stockholm (SE).
`P. 0. Box 17704, S-118 93 Stockholm (SE).
`
`
`(81) Designated States: AM, AT, AU, BB, BG, BR, BY, CA, CH, (81) Designated States: AM, AT, AU, BB, BG, BR, BY, CA, CH,
`
`CN, CZ, DE, DK, ES, Fl, GB, GE, HU, JP, KE, KG, KP, CN, CZ, DE, DK, ES, FI, GB, GE, BU, JP, KE, KG, KP,
`
`KR, KZ, LK, LT, LU, LV, MD, MG, MN, MW, NL, NO, KR, KZ, LK, LT, LU, LV, MD, MG, MN, MW, NL, NO,
`NZ, PL, PT, RO, RU, SD, SE, SI, SK, TJ, TT, UA, US, NZ, PL, PT, RO, RU, SD, SE, SI, SK, TJ, TT, UA, US,
`
`
`UZ, VN, European pat~nt (AT, BE, CH, DE, DK, ES, FR, UZ, VN, European pat~nt (AT, BE, CH, DE, DK, ES, FR,
`GB, GR, IE, IT, LU, MC, NL, PT, SE), OAPI patent (BF, GB, GR, IE, IT, LU, MC, NL, PT, SE), OAPI patent (BF,
`
`BJ, CF, CG, CI, CM, GA, GN, ML, MR, NE, SN, TD, TG),
`BJ, CF, CG, CI, CM, GA, GN, ML, MR, NE, SN, TD, TG),
`ARIPO patent (KE, MW, SD, SZ).
`ARIPO patent (KE, MW, SD, SZ).
`
`
`Published Published
`
`With international search report. With international search report.
`
`Before the expiration of the time limit for amending the Before the expiration of the time limit for amending the
`
`claims and to be republished in the event of the receipt of claims and to be republished in the event of the receipt of
`
`amendments. amendments.
`
`
`
`I I
`
`Al
`A1
`
`
`
`(54) Title: AN ELECTRIC MOTOR AND ITS FABRICATION (54) Title: AN ELECTRIC MOTOR AND ITS FABRICATION
`
`
`
`(57) Abstract (57) Abstract
`
`
`In a brushless electric motor/generator there are In a brushless electric motor/generator there are
`
`poles (30 I, 401) which are separate mechanical parts poles (30 I, 40 1) which are separate mechanical parts
`and are assembled to form a stator. The poles (301, and are assembled to form a stator. The poles (301,
`
`401) comprises outer portions (304, 404) projecting
`401) comprises outer portions (304, 404) projecting
`
`in a circumferential direction from the main leg of in a circumferential direction from the main leg of
`
`the poles. the poles.
`
`These outer portions (304, 404) are These outer portions (304, 404) are
`
`engaged with each other, thus forming a magnetic engaged with each other, thus forming a magnetic
`
`yoke carrying magnetic flux between the poles. This yoke carrying magnetic flux between the poles. This
`
`permits an easy winding of the separate poles and a permits an easy winding of the separate poles and a
`
`good support thereof by an outer ring. good support thereof by an outer ring.
`
`5021
`502 1
`
`I I
`
`
`
`-----+----------+-----
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`
`I I
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`Page 1 of 36
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`PETITIONERS' EXHIBIT 1017
`
`

`

`
`
`FOR THE PURPOSES OF INFORMATION ONLY FOR THE PURPOSES OF INFORMATION ONLY
`
`
`Codes used to identify States party to the PCT on the front pages of pamphlets publishing international Codes used to identify States party to the PCT on the front pages of pamphlets publishing international
`applications under the PCT.
`applications under the PCT.
`
`AT
`AT
`AU
`AU
`BB
`BB
`BE
`BE
`BF
`BF
`BG
`BG
`
`BJ BJ
`BR
`BR
`BY
`BY
`
`CA CA
`CF
`CF
`
`CG CG
`
`CH CH
`CI
`CI
`CM
`CM
`CN
`CN
`cs
`CS
`cz
`CZ
`DE
`DE
`
`DK DK
`ES
`ES
`
`FI FI
`
`FR FR
`
`GA GA
`
`Austria
`Austria
`Australia
`Australia
`Barbados
`Barbados
`Belgium
`Belgium
`
`Burkina Faso Burkina Faso
`
`Bulgaria Bulgaria
`
`Benin Benin
`BrdZil
`BrdZil
`
`Belarus Belarus
`
`Canada Canada
`Central African Republic
`Central African Republic
`
`Congo Congo
`
`Switzerland Switzerland
`Cote d'Ivoire
`Cote d'Ivoire
`
`Cameroon Cameroon
`China
`China
`
`Czechoslovakia Czechoslovakia
`
`Czech Republic Czech Republic
`Germany
`Germany
`
`Denmark Denmark
`Spain
`Spain
`
`Finland Finland
`France
`France
`
`Gabon Gabon
`
`GB
`GB
`GE
`GE
`GN
`GN
`GR
`GR
`HV
`HU
`IE
`IE
`
`IT IT
`JP
`JP
`KE
`KE
`
`KG KG
`
`KP KP
`
`
`KR KR
`KZ
`KZ
`
`LI LI
`LK
`LK
`
`LU LU
`
`LV LV
`MC
`MC
`MD
`MD
`MG
`MG
`ML
`ML
`
`MN MN
`
`United Kingdom
`United Kingdom
`Georgia
`Georgia
`Guinea
`Guinea
`Greece
`Greece
`
`Hungary Hungary
`Ireland
`Ireland
`Italy
`Italy
`
`Japan Japan
`
`Kenya Kenya
`Kyrgystan
`Kyrgystan
`
`Democratic People's Republic Democratic People's Republic
`of Korea
`of Korea
`
`Republic of Korea Republic of Korea
`Kazakhstan
`Kazakhstan
`
`Liechtenstein Liechtenstein
`Sri Lanka
`Sri Lanka
`
`Luxembourg Luxembourg
`Latvia
`Latvia
`Monaco
`Monaco
`Republic of Moldova
`Republic of Moldova
`
`Madagascar Madagascar
`Mali
`Mali
`
`Mongolia Mongolia
`
`
`MR MR
`MW
`MW
`NE
`NE
`NL
`NL
`
`NO NO
`NZ
`NZ
`PL
`PL
`
`PT PT
`
`RO RO
`RU
`RU
`
`SD SD
`SE
`SE
`SI
`SI
`SK
`SK
`
`SN SN
`TD
`TD
`
`TG TG
`
`TJ TJ
`IT
`TI
`UA
`VA
`us
`US
`uz
`UZ
`
`VN VN
`
`
`Mauritania Mauritania
`Malawi
`Malawi
`Niger
`Niger
`Netherlands
`Netherlands
`
`Norway Norway
`New Zealand
`New Zealand
`Poland
`Poland
`
`Portugal Portugal
`
`Romania Romania
`Russian Federation
`Russian Federation
`Sudan
`Sudan
`Sweden
`Sweden
`Slovenia
`Slovenia
`Slovakia
`Slovakia
`
`Senegal Senegal
`Chad
`Chad
`
`Togo Togo
`
`Tajikistan Tajikistan
`Trinidad and Tobago
`Trinidad and Tobago
`Ukraine
`Ukraine
`
`United States of America United States of America
`Uzbekistan
`Uzbekistan
`
`VietNam Viet Nam
`
`Page 2 of 36
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`

`

`..
`..
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`wo 95/12912
`WO 95/12912
`
`PCT/SE94/01026
`PCT/SE94/01026
`
`1
`1
`
`AN ELECTRIC MOTOR AND ITp FABRICATION
`AN ELECTRIC MOTOR AND ITp FABRICATION
`Technical Field
`Technical Field
`
`The invention is concerned with methods of designing and The invention is concerned with methods of designing and
`producing stators for in particular brushless motors/generators
`producing stators for in particular brushless motors/generators
`and the motorjgenerator stators and motors/generators thus
`and the motor/generator stators and motors/generators thus
`produced.
`produced.
`
`Background of the invention and prior art Background of the invention and prior art
`
`To obtain highly efficient electrical motors some To obtain highly efficient electrical motors some
`requirements are commonly understood. The design should give
`requirements are commonly understood. The design should give
`short amounts of current conducting winding material that is
`short amounts of current conducting winding material that is
`outside the stator parts that are highly permeable for magnetic
`outside the stator parts that are highly permeable for magnetic
`flux. The design should also permit much current conducting
`flux. The design should also permit much current conducting
`winding material in the winding slots. Further, the thermal path
`winding material in the winding slots. Further, the thermal path
`
`between the current conducting winding material and the between the current conducting winding material and the
`
`intermediate heat sink like the outer housing of the motor should intermediate heat sink like the outer housing of the motor should
`be good enough to keep the winding temperature at an acceptable
`be good enough to keep the winding temperature at an acceptable
`level at power losses that the outer casing can dissipate at
`level at power losses that the outer casing can dissipate at
`acceptable surface temperatures. The design should also give
`acceptable surface temperatures. The design should also give
`stators that are mechanically robust.
`stators that are mechanically robust.
`
`Brushless DC motors have their windings in the stator. Most Brushless DC motors have their windings in the stator. Most
`
`stators are three-phase and have stator windings similar to that stators are three-phase and have stator windings similar to that
`of a three phase induction motor.
`of a three phase induction motor.
`Almost all electric motors with alternating current stator
`Almost all electric motors with alternating current stator
`
`windings (including brushless DC motors and induction motors) in windings (including brushless DC motors and induction motors) in
`sizes up to some 10 kW have their stators made of lamination
`sizes up to some 10 kW have their stators made of lamination
`sheets that cover the whole circumference of the motor. These
`sheets that cover the whole circumference of the motor. These
`
`punched laminations are assembled together by welding or other punched laminations are assembled together by welding or other
`means to form a rigid hollow cylinder. Thereafter the winding
`means to form a rigid hollow cylinder. Thereafter the winding
`slots are insulated. The windings are wound outside the stator
`slots are insulated. The windings are wound outside the stator
`
`and thereafter inserted in the slots. This method does give two and thereafter inserted in the slots. This method does give two
`
`disadvantages. disadvantages.
`
`The first disadvantage is that it does not permit a very The first disadvantage is that it does not permit a very
`
`orderly arrangement of the winding wires in the winding slots. In orderly arrangement of the winding wires in the winding slots. In
`
`order to obtain a very high utilization of a winding slot in a order to obtain a very high utilization of a winding slot in a
`
`stator, the wires should run parallel to each other. For wires of stator, the wires should run parallel to each other. For wires of
`circular cross-section, a hexagonal arrangement where each wire
`circular cross-section, a hexagonal arrangement where each wire
`is surrounded by six other wires is normally the most efficient
`is surrounded by six other wires is normally the most efficient
`
`arrangement. arrangement.
`
`The second disadvantage is that a prewound winding coil must The second disadvantage is that a prewound winding coil must
`
`CONFIRMATION
`CONFIRMATION
`COpy
`COPY
`
`Page 3 of 36
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`

`

`wo 95/12912
`WO 95/12912
`
`PCT/SE94/01026
`PCT/SE94/01026
`
`
`
`2 2
`
`
`have a considerable surplus length to permit insertion in a have a considerable surplus length to permit insertion in a
`
`stator winding slot. In the case of overlapping polyphase stator winding slot. In the case of overlapping polyphase
`
`windings, a certain excess length is required to permit insertion windings, a certain excess length is required to permit insertion
`
`of a winding without being locked by the other phases. In the of a winding without being locked by the other phases. In the
`
`case of salient poles, a certain excess length is required to as case of salient poles, a certain excess length is required to as
`
`the winding must be heeled over the pole tooth head portions. the winding must be heeled over the pole tooth head portions.
`
`This results in unnecessary current conducting winding material This results in unnecessary current conducting winding material
`
`that is outside the stator parts that are highly permeable for that is outside the stator parts that are highly permeable for
`
`magnetic flux. magnetic flux.
`
`Figure 1 illustrates a rolled-out view of a conventional Figure 1 illustrates a rolled-out view of a conventional
`
`stator with overlapping phases as seen from the rotor. stator with overlapping phases as seen from the rotor.
`
`The arc 101 shows one part of the current conducting winding The arc 101 shows one part of the current conducting winding
`
`104 that is not inserted inside the flux permeable part of the 104 that is not inserted inside the flux permeable part of the
`
`stator, while 103 shows a part that is inserted inside the flux stator, while 103 shows a part that is inserted inside the flux
`
`permeable part of the stator. 102 shows the stator pole as seen permeable part of the stator. 102 shows the stator pole as seen
`
`from the rotor. from the rotor.
`
`Figure 2 illustrates a rolled-out view of a conventional Figure 2 illustrates a rolled-out view of a conventional
`
`stator as seen from the rotor of a brushless motor as disclosed stator as seen from the rotor of a brushless motor as disclosed
`
`in the published International patent application WO-A1 92/06530. in the published International patent application WO-A1 92/06530.
`
`These motors, and motors as disclosed in the published These motors, and motors as disclosed in the published
`
`International patent application WO-A1 93/15547, have windings International patent application WO-A1 93/15547, have windings
`
`consisting of groups of stator poles 201, each having a simple consisting of groups of stator poles 201, each having a simple
`
`coils 202 around it. In the case of motors as disclosed in the coils 202 around it. In the case of motors as disclosed in the
`
`cited International patent application WO-A1 92/06530, the gaps cited International patent application WO-A1 92/06530, the gaps
`
`between different pole groups are bridged by balancing poles 203. between different pole groups are bridged by balancing poles 203.
`
`A common problem in the winding of motor stators is to reduce A common problem in the winding of motor stators is to reduce
`
`the amounts of current conducting winding material that is the amounts of current conducting winding material that is
`
`outside the flux high permeable stator parts. This material is outside the flux high permeable stator parts. This material is
`
`shown separately as 101 and 204 in figures 1 and 2 respectively. shown separately as 101 and 204 in figures 1 and 2 respectively.
`
`The US patent 3,792,299 discloses a stator for an electric The US patent 3,792,299 discloses a stator for an electric
`
`motor comprising an outer annual yoke and a plurality of radially motor comprising an outer annual yoke and a plurality of radially
`
`directed stator teeth. In another embodiment (figure 7) in the directed stator teeth. In another embodiment (figure 7) in the
`
`same patent, the yoke is assembled of a plurality of yoke parts. same patent, the yoke is assembled of a plurality of yoke parts.
`
`In both cases, the flux carrying parts of the stator consists of In both cases, the flux carrying parts of the stator consists of
`
`separately punched stator teeth. The winding of the stator is separately punched stator teeth. The winding of the stator is
`
`made by first arranging the stator teeth so that during the made by first arranging the stator teeth so that during the
`
`winding procedure, the slot spaces for the stator winding will be winding procedure, the slot spaces for the stator winding will be
`
`open radially outwards. This permits a winding with far less open radially outwards. This permits a winding with far less
`
`surplus length as there is more freedom in adjusting the coils of surplus length as there is more freedom in adjusting the coils of
`
`Page 4 of 36
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`

`

`wo 95/12912
`WO 95/12912
`
`
`
`PCT/SE94/0 1026 PCT/SE94/0 1026
`
`3
`3
`
`
`the different phases of the winding to each other during the different phases of the winding to each other during
`
`assembly. After the winding procedure these openings are closed assembly. After the winding procedure these openings are closed
`by a stator ring or yoke, whereafter moulding together of
`by a stator ring or yoke, whereafter moulding together of
`
`winding, stator teeth and stator yoke is carried out by means of winding, stator teeth and stator yoke is carried out by means of
`
`lacquer or moulding compound to a rigidly assembled stator unit. lacquer or moulding compound to a rigidly assembled stator unit.
`The US patent 3,353,046 discloses a stator produced from a
`The US patent 3,353,046 discloses a stator produced from a
`
`cog-wheel shaped stator teeth set. After winding, impregnation cog-wheel shaped stator teeth set. After winding, impregnation
`with a thermosetting resin and baking, the resulting solid body
`with a thermosetting resin and baking, the resulting solid body
`is ground down to an outer diameter that fits an outer, cylinder
`is ground down to an outer diameter that fits an outer, cylinder
`shaped yoke ring. After that the yoke cylinder is assembled and
`shaped yoke ring. After that the yoke cylinder is assembled and
`
`fixed by another impregnation and baking process, the common base fixed by another impregnation and baking process, the common base
`
`of all the stator teeth is ground down from the inside so that of all the stator teeth is ground down from the inside so that
`
`the base disappears and the required gaps between each stator the base disappears and the required gaps between each stator
`tooth appears.
`tooth appears.
`The us patents 2,459,673, 2,517,105, 2,654,037, 2,655,613,
`The US patents 2,459,673, 2,517,105, 2,654,037, 2,655,613,
`
`2,687,483, 2,691,113, 2,745,031, 3,449,607, 3,549,926, 3,612,930, 2,687,483, 2,691,113, 2,745,031, 3,449,607, 3,549,926, 3,612,930,
`
`3,740,600, 4,246,505, 4,433,262 and 4,816,710 and the published 3,740,600, 4,246,505, 4,433,262 and 4,816,710 and the published
`
`International patent application WO-A1 92/10021 disclose various International patent application WO-A1 92/10021 disclose various
`ways to design electrical machines with yokeless separate salient
`ways to design electrical machines with yokeless separate salient
`poles which are assembled on a stator or rotor yoke. Most or all
`poles which are assembled on a stator or rotor yoke. Most or all
`of these designs have solid (not laminated) poles andjor yokes
`of these designs have solid (not laminated) poles and/or yokes
`and seem to be designed exclusively for poles with DC current
`and seem to be designed exclusively for poles with DC current
`
`coils to be used as stator field magnets (interacting with coils to be used as stator field magnets (interacting with
`
`laminated rotors in mechanically commutated DC machines) or rotor laminated rotors in mechanically commutated DC machines) or rotor
`poles for synchronous machines (interacting with laminated three(cid:173)
`poles for synchronous machines (interacting with laminated three(cid:173)
`phase stators).
`phase stators) .
`The published International patent application WO-A1 92/03870
`The published International patent application WO-A1 92/03870
`
`discloses a design where laminated salient poles can be assembled discloses a design where laminated salient poles can be assembled
`
`into a laminated stator yoke. The assembled stator shape into a laminated stator yoke. The assembled stator shape
`
`corresponds to stators commonly as field in a mechanically corresponds to stators commonly as field in a mechanically
`
`commutated DC machine). commutated DC machine).
`
`Summary Summary
`A purpose of the invention is to provide a brushless motor
`A purpose of the invention is to provide a brushless motor
`stator that permits much current conducting winding material in
`stator that permits much current conducting winding material in
`the winding slots.
`the winding slots.
`
`Another purpose of the invention is to provide a brushless Another purpose of the invention is to provide a brushless
`
`motor stator that give short amounts of current conducting motor stator that give short amounts of current conducting
`winding material that is outside the stator parts that are highly
`winding material that is outside the stator parts that are highly
`
`permeable for magnetic flux. permeable for magnetic flux.
`
`Page 5 of 36
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`

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`wo 95/12912
`WO 95/12912
`
`PCT/SE94/01026
`PCT/SE94101026
`
`4
`4
`
`
`Another purpose of the i~vention is to provide a brushless Another purpose of the i~vention is to provide a brushless
`
`motor stator that permits a low thermal impedance to the motor stator that permits a low thermal impedance to the
`
`intermediate heat sink. intermediate heat sink.
`Another purpose of the invention is to provide a brushless
`Another purpose of the invention is to provide a brushless
`
`motor stator that permits automated, space efficient winding of motor stator that permits automated, space efficient winding of
`
`the winding wire. the winding wire.
`Another purpose of the invention is to provide a brushless
`Another purpose of the invention is to provide a brushless
`
`motor stator that permits the use of oriented stator material. motor stator that permits the use of oriented stator material.
`
`Another purpose of the invention is to provide a brushless Another purpose of the invention is to provide a brushless
`
`motor stator that permits efficient use of the rolled material motor stator that permits efficient use of the rolled material
`
`used for the laminated stator, thus permitting the use of higher used for the laminated stator, thus permitting the use of higher
`
`cost high quality rolled material. cost high quality rolled material.
`
`Another purpose of the invention is to provide a brushless Another purpose of the invention is to provide a brushless
`motor stator that permits small interpole airgaps between the
`motor stator that permits small interpole airgaps between the
`stator teeth close to the stator to rotor air gap, and that
`stator teeth close to the stator to rotor air gap, and that
`
`permits this also in case of large diameter winding wire. permits this also in case of large diameter winding wire.
`
`Another purpose of the invention is to provide a brushless Another purpose of the invention is to provide a brushless
`
`motor stator that has a low weight. motor stator that has a low weight.
`
`Another purpose of the invention is to provide a brushless Another purpose of the invention is to provide a brushless
`
`motor stator where little axial space is required in front etch motor stator where little axial space is required in front etch
`
`and rear of the magnetically permeable part of the stator. and rear of the magnetically permeable part of the stator.
`Another purpose of the invention is to provide a brushless
`Another purpose of the invention is to provide a brushless
`motor stator that efficiently can be cooled by forced air
`motor stator that efficiently can be cooled by forced air
`ventilation.
`ventilation.
`
`The problems discussed above are solved by and the above The problems discussed above are solved by and the above
`mentioned purposes are achieved by the invention, the
`mentioned purposes are achieved by the invention, the
`
`characteristics of which appear from the appended claims. characteristics of which appear from the appended claims.
`
`The invention thus permits the design and production of The invention thus permits the design and production of
`
`stators for electrical machines with alternating current salient stators for electrical machines with alternating current salient
`stator poles that have very short amounts of current conducting
`stator poles that have very short amounts of current conducting
`
`winding material that is outside the flux high permeable stator winding material that is outside the flux high permeable stator
`
`parts, that permits much current conducting winding material in parts, that permits much current conducting winding material in
`
`the winding slots, that have an excellent thermal path between the winding slots, that have an excellent thermal path between
`the current conducting winding material and the intermediate heat
`the current conducting winding material and the intermediate heat
`
`sink like the outer housing of the motor. It also gives very high sink like the outer housing of the motor. It also gives very high
`
`utilization of the rolled sheet material used for the stator utilization of the rolled sheet material used for the stator
`laminations and permits the use of anisotropic magnetic
`laminations and permits the use of anisotropic magnetic
`
`materials. materials.
`
`The stator is thus built of separate parts that acts as The stator is thus built of separate parts that acts as
`
`Page 6 of 36
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`

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`wo 95/12912
`WO 95/12912
`
`PCT/SE94/0 1026
`PCT/SE94/0 1026
`
`
`
`5 5
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`combined single poles and yo~e arch segments. Each of these
`combined single poles and yo~e arch segments. Each of these
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`segments constitutes a part of the whole circumference of the segments constitutes a part of the whole circumference of the
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`yoke. Generally there thus in an electric motor/generator poles yoke. Generally there thus in an electric motor/generator poles
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`which are separate parts and are assembled to form a stator. The which are separate parts and are assembled to form a stator. The
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`poles comprise outer portions projecting in a circumferential poles comprise outer portions projecting in a circumferential
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`direction from the main leg of the poles. These outer portions direction from the main leg of the poles. These outer portions
`are engaged with each other, thus forming a magnetic yoke
`are engaged with each other, thus forming a magnetic yoke
`carrying magnetic flux between the poles.
`carrying magnetic flux between the poles.
`
`Brief description of the drawings Brief description of the drawings
`The invention may be better understood from the following
`The invention may be better understood from the following
`
`detailed description when read with reference to the drawings in detailed description when read with reference to the drawings in
`which:
`which:
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`Figure 1 schematically shows a common stator winding with Figure 1 schematically shows a common stator winding with
`overlapping phases as seen from the rotor.
`overlapping phases as seen from the rotor.
`Figure 2 schematically shows a prior stator winding without
`Figure 2 schematically shows a prior stator winding without
`overlapping phases as seen from the rotor.
`overlapping phases as seen from the rotor.
`Figure 3 shows a side view of a stator pole that constitutes
`Figure 3 shows a side view of a stator pole that constitutes
`a coil carrying stator arch segment in an electric motor.
`a coil carrying stator arch segment in an electric motor.
`Figure 4 shows a side view a stator pole of the electric
`Figure 4 shows a side view a stator pole of the electric
`motor that acts as an unwound flux balancing stator arch segment.
`motor that acts as an unwound flux balancing stator arch segment.
`Figure 5 shows an axial view of the flux carrying parts of a
`Figure 5 shows an axial view of the flux carrying parts of a
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`complete stator. complete stator.
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`Figures 6a and 6b show an assembled stator in cross-sectional Figures 6a and 6b show an assembled stator in cross-sectional
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`views in an axial plane and a radial plane respectively. views in an axial plane and a radial plane respectively.
`Figure 7 shows a punch layout of the stator parts according
`Figure 7 shows a punch layout of the stator parts according
`to figure 3.
`to figure 3.
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`Figure 8 shows a perspective view, as seen obliquely from the Figure 8 shows a perspective view, as seen obliquely from the
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`rotor, of three stator poles according to figure 3 and one pole rotor, of three stator poles according to figure 3 and one pole
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`according to figure 4 together with six devices acting as coil according to figure 4 together with six devices acting as coil
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`end winding supports and pole gap fixtures. end winding supports and pole gap fixtures.
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`Figure 9 shows a section along a radial plan of a winded Figure 9 shows a section along a radial plan of a winded
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`stator pole illustrating how devices according to figure 8 acts stator pole illustrating how devices according to figure 8 acts
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`as a coil winding support and pole gap fixture. as a coil winding support and pole gap fixture.
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`Figures lOa and lOb show an assembled stator using coil end Figures lOa and lOb show an assembled stator using coil end
`winding support and pole gap fixtures according to figure 8 in
`winding support and pole gap fixtures according to figure 8 in
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`axial and radial cross-sectional views respectively. axial and radial cross-sectional views respectively.
`Figure 11 shows a side view of a portion of the stator of a
`Figure 11 shows a side view of a portion of the stator of a
`linear motor using anisotropic materials.
`linear motor using anisotropic materials.
`Figures 12a and 12 show an assembled stator in axial and
`Figures l2a and 12 show an assembled stator in axial and
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`Page 7 of 36
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`

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`wo 95/12912
`WO 95/12912
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`PCT/SE94/01026
`PCT/SE94/01026
`
`6
`6
`
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`radial sections respectively~ radial sections respectively~
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`Figure 13 shows a section along a tangential plane through a Figure 13 shows a section along a tangential plane through a
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`wound stator pole with winding support fixtures according to wound stator pole with winding support fixtures according to
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`figure 8. figure 8.
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`Figure 14 shows an axial view of a coil end winding support Figure 14 shows an axial view of a coil end winding support
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`and pole gap fixtures according to figure 8 designed to permit an and pole gap fixtures according to figure 8 designed to permit an
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`odd number of winding layers. odd number of winding layers.
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`Figure 15 shows an axial view of a stator having interlocking Figure 15 shows an axial view of a stator having interlocking
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`surfaces on the stator parts. surfaces on the stator parts.
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`Detailed description Detailed description
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`The invention will now be described using exemplary The invention will now be described using exemplary
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`embodiments suited to electrical machines like those disclosed in embodiments suited to electrical machines like those disclosed in
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`the cited WO-A1 92/06530 and WO-A1 93/15547. The description is the cited WO-A1 92/06530 and WO-A1 93/15547. The description is
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`only given in explanatory and clarifying purposes and is not only given in explanatory and clarifying purposes and is not
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`intended to limit the invention. intended to limit the invention.
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`Figure 3 shows an axial view of a stator pole that Figure 3 shows an axial view of a stator pole that
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`constitutes an arch segment of a stator of an electric motor. The constitutes an arch segment of a stator of an electric motor. The
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`pole 301 has an outer, basically circular-cylindrical segment pole 301 has an outer, basically circular-cylindrical segment
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`side or surface 302 that in the assembled motor faces the motor side or surface 302 that in the assembled motor faces the motor
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`casing, an opposite and concentric, inner, basically circular(cid:173)casing, an opposite and concentric, inner, basically circular(cid:173)
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`cylindrical segment side or surface 303 that in the assembled cylindrical segment side or surface 303 that in the assembled
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`motor faces the rotor, two basically radially oriented sides 304 motor faces the rotor, two basically radially oriented sides 304
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`and 305 that in the assembled motor faces the adjoining stator and 305 that in the assembled motor faces the adjoining stator
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`parts, and a centre pole leg 306 intended to carry a winding. It parts, and a centre pole leg 306 intended to carry a winding. It
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`is obvious that the pole can be very easily wound with a very is obvious that the pole can be very easily wound with a very
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`efficient winding with much current conducting winding material efficient winding with much current conducting winding material
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`in the winding slots. As the pole leg 306 being a separate part in the winding slots. As the pole leg 306 being a separate part
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`is freely accessible from all sides, automatic winding machines is freely accessible from all sides, automatic winding machines
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`can wind a winding thereon with optimal stacking of the wire can wind a winding thereon with opt