Electromagnet design for high-flux applications

Abstract

An electromagnet includes a cylindrical core and a bobbin. The bobbin has a first barrel portion bounded by a first flange and a second flange. The bobbin also includes a second barrel portion bounded by the second flange and a third flange. The first flange has a diameter that is greater than a diameter of the third flange. The bobbin also includes an aperture extending through the first barrel portion and the second barrel portion, wherein the core is disposed within the aperture. A wire is wound around the first barrel portion to define a first portion of a coil and is wound around the second barrel portion to define a second portion of the coil. A power source provides a current through the wire.

Description

Background Technology

[0001] Magnets have wide applications in the modern world, such as in brakes, motors, and generators. They can generally be classified into permanent magnets and electromagnets. Permanent magnets typically retain their magnetic strength after magnetization and serve as a direct source of magnetic fields. In contrast, electromagnets utilize coils typically surrounding a magnetic core and a current source to generate a magnetic field. Because the magnetic field generated by an electromagnet is only effective when current flows through the coil, the electromagnet can selectively switch between "on" and "off" states by controlling the current flowing through the coil.

[0002] For magnetic machines, such as the aforementioned brakes, motors, and generators, the magnetic field strength provided by the magnets is a crucial factor in machine performance. These machines typically utilize magnetic arrays to provide high-power magnetic fields. Magnetic arrays usually consist of a series of permanent magnets, electromagnets, or a combination of both. A common example of a magnet array configuration is the Halbach array, which is a specific arrangement of magnets that enhances the magnetic field on one side of the array. The use of such magnet arrangements varies depending on the application and magnetic flux requirements. Hybrid arrays are magnetic arrays that combine permanent magnets and electromagnets. These arrays offer the flexibility to enhance or limit the magnetic flux output from the machine.

[0003] When a current-carrying conductor is wound around a cylindrical ferromagnetic body, a magnetic field is induced within that ferromagnetic body. The multiple turns of conductor wound around the core are collectively called a solenoid. The magnetic field strength in the ferromagnetic body (also called the core) is the sum of the fields generated in each individual loop of the solenoid. The magnetic flux produced by a current-carrying solenoid depends on the number of turns in the conductor and the magnitude of the current. Therefore, increasing the number of coils increases the maximum magnetic flux density in the core, up to the magnetic saturation limit of the core itself. The generated magnetic flux is guided through the pole shoes at the ends of the core, which are typically effective indicators of the flux output.

[0004] Figure 12 A schematic view of an electromagnetic device 50 is shown. The electromagnetic device 50 includes a housing 52, and a rotor 54 mounted on a shaft 56 to rotate about an axis 58. The rotor is at least partially formed of a conductive material. A corresponding stator 60 is mounted within the housing 52 and is fixed in place to prevent rotation. The stator generates an electromagnetic field. As the rotor moves through the electromagnetic field, eddy currents are generated in the stator, resulting in resistance on the rotor, i.e., braking force. Summary of the Invention

[0005] This disclosure provides examples of electromagnets and electromagnetic field arrays utilizing one or more of these electromagnets. In one embodiment, the electromagnet includes a core and a coil frame. The coil frame has a first cylindrical portion defined by a first flange extending radially from a first end of the first cylindrical portion and a second flange extending radially from a second end of the first cylindrical portion. A second cylindrical portion of the coil frame is defined by a second flange at a first end of the second cylindrical portion and a third flange extending radially from a second end of the second cylindrical portion. The diameter of the first flange is larger than the diameter of the third flange. An orifice extends through the first and second cylindrical portions, and the core is disposed within the orifice. A conductor is wound around the first cylindrical portion to define a first portion of the coil and wound around the second cylindrical portion to define a second portion of the coil. A power source provides current through the conductor.

[0006] In any embodiment, the electromagnet also includes a pole piece disposed at one end of the core.

[0007] In any embodiment, the diameter of the first portion of the coil is greater than the diameter of the second portion of the coil.

[0008] In any embodiment, a groove is formed in the second flange, the groove extending outward from the first cylindrical portion, and a wire extends through the groove between the first coil portion and the second coil portion.

[0009] In any embodiment, the groove is tangent to the first cylindrical portion.

[0010] In any embodiment, the electromagnetic array includes a ring support and a disclosed electromagnet, wherein pole shoes are coupled to the ring support.

[0011] In any embodiment, the electromagnetic array further includes a spacer disposed between the pole shoe and the annular support.

[0012] In any embodiment, the annular support includes an internal spline surface.

[0013] In any embodiment, the annular support also includes an annular base and a plurality of permanent magnets coupled to the base.

[0014] In any embodiment, each permanent magnet includes a recess and / or cutout, and the annular base includes ridges extending radially into the recess and / or cutout of each permanent magnet.

[0015] In any embodiment, the permanent magnet and pole shoe cooperate to define a flat surface.

[0016] In any embodiment, the electromagnetic array includes a ring support and a plurality of disclosed electromagnets, wherein the pole shoes of each electromagnet are coupled to the ring support.

[0017] In any embodiment, the electromagnets of the plurality of electromagnets are evenly spaced around the annular support.

[0018] In any embodiment, a gasket is provided between each pole shoe and the annular support.

[0019] In any embodiment, the electromagnetic brake includes a stator, which includes the disclosed electromagnetic array.

[0020] This summary introduces a selection of concepts in a simplified form, which will be further described in the detailed description below. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to help determine the scope of the claimed subject matter. Attached Figure Description

[0021] The above aspects and many accompanying advantages of this disclosure will become more readily understood when taken in conjunction with the accompanying drawings and the following detailed description, wherein:

[0022] Figure 1 It is a front-view isometric view of an electromagnetic array according to various aspects of this disclosure;

[0023] Figure 2 It is its rear isometric view;

[0024] Figure 3 It is a partially decomposed front isometric view;

[0025] Figure 4 It is a partially decomposed rear isometric view;

[0026] Figure 5 This is its rear front view;

[0027] Figure 6 Is it like this? Figure 5 The partial cross-sectional view indicated in the middle;

[0028] Figure 7 Is it like this? Figure 5 The partial cross-sectional view indicated in the middle;

[0029] Figure 8 yes Figure 1 Rear isometric view of the electromagnet assembly of the electromagnetic array shown.

[0030] Figure 9 yes Figure 8 A side front view of the electromagnet assembly, with the cover removed;

[0031] Figure 10 yes Figure 8 Rear isometric view of the core and pole shoes of the electromagnet assembly;

[0032] Figure 11 yes Figure 8 A front isometric view of the coil frame of the electromagnet assembly; and

[0033] Figure 12 It is a schematic view of an electromagnetic device including a rotor and a stator. Detailed Implementation

[0034] The specific embodiments described below with reference to the accompanying drawings (where like reference numerals refer to like elements) are intended to describe various embodiments of the disclosed subject matter and are not intended to represent only those embodiments. Each embodiment described in this disclosure is provided by way of example or illustration only and should not be construed as superior to or having an advantage over other embodiments. The illustrative examples provided herein are not intended to be exhaustive or to limit the claimed subject matter to the precise forms disclosed.

[0035] The following discussion provides examples of electromagnets and electromagnetic arrays used as stators in various electromagnetic devices, including “eddy currents,” i.e., electromagnetic brakes. Embodiments of electromagnetic brakes can be used in vehicles, and particularly aircraft, where high magnetic flux needs to be generated within a confined space.

[0036] Figures 1 to 7 Representative embodiments of an electromagnetic array 100 (hereinafter referred to as "array 100" or "array") according to various aspects of this disclosure are shown. Figure 1 and Figure 2 As best shown, array 100 includes a generally annular support 110 to which a plurality of electromagnets 200 are mounted. In the illustrated embodiment, array 100 includes four electromagnets 200 arranged in a uniformly spaced circular pattern, i.e., at approximately 90° intervals. In any embodiment, the number and position of the electromagnets 200 can be varied in any suitable manner. In any embodiment, the array may include one, two, three, five, or any other suitable number of electromagnets 200. In any embodiment, the electromagnets 200 may be uniformly or non-uniformly spaced around the support 110. In any embodiment, the radial distance of the electromagnets from the center of the support 110 may vary.

[0037] As will be described below, in addition to providing a mounting structure for the electromagnet 200, the support 110 also provides a locking feature to fix the array 100 in a fixed position so that it cannot be rotated, thereby allowing the array to be used as a stator in an electromagnetic device. Furthermore, in the illustrated embodiment, the support 110 includes a plurality of permanent magnets that cooperate with the electromagnet to provide a “hybrid” array 100.

[0038] like Figure 3 and Figure 4As best shown, support 110 includes an annular base 120. Base 120 has a generally flat annular base plate 122, with an inner spline feature extending through the central portion of the base plate. The spline feature 124 is sized and configured to engage with the complementary outer spline of an electromagnetic device on which the array 100 is used. Engagement of spline feature 124 with the complementary surface of the electromagnetic device secures the array 100 to a non-rotatable state, allowing the array to function as a stator. In some embodiments, the spline feature is an outer spline engaging the inner spline, which is secured to a non-rotatable state. In some embodiments, the support is secured to a non-rotatable state by any suitable mounting construction or locking mechanism.

[0039] Multiple apertures 126 extend through the substrate 122. The size and position of the apertures 126 are set such that for each aperture, a corresponding electromagnet 200 mounted to the support 110 extends through the aperture.

[0040] like Figure 3 As best shown, the annular ridge 128 extends radially outward from the outer portion of the spline feature 124. The ridge 128 is parallel to and offset from the substrate 122. The portion of the ridge 128 adjacent to the aperture 126 extends further in the radial direction to define a mounting feature 130 to which the electromagnet 200 is fixed.

[0041] Still referencing Figure 3 The support member 110 includes a permanent magnet assembly 140 (hereinafter referred to as "magnet assembly 140" or "magnet assembly"). The magnet assembly 140 includes a plurality of tapered permanent magnets 142, each magnet having an arcuate inner surface 144 (having a first diameter) and an arcuate outer surface 146 (having a second diameter greater than the first diameter). Recesses 148 are formed along the inner surface 144 of each magnet, and their dimensions and configuration are set to be part of a ridge 128 of the receiving base 120. The plurality of magnets 142 are arranged sequentially to form part of an annular magnet that extends between adjacent mounting features. When the plurality of magnets 142 are arranged in this manner, the recesses 148 of the magnets are aligned to form a single recess that receives part of the ridge 128 of the base 120. It should be understood that the number, size, and configuration of one or more magnets 142 can vary in any suitable manner.

[0042] The outer ring 160 has a generally cylindrical body 162 with an inner surface sized to engage the outer surface 146 of each magnet 142 of the magnet assembly 140 when the array 100 is assembled. The outer ring also includes a plurality of arcuate retaining features 164 arranged such that each retaining feature engages and provides support for one of the electromagnets 200 mounted to the support 110. Figure 3 and Figure 4As shown, the outer ring 160 is secured to the base 120 by a plurality of fasteners 180.

[0043] Now for reference Figure 7 When the array is assembled, a portion of the ridge 128 extends into the recess 148 of each magnet 142 of the magnet assembly 140, and the face of each magnet 142 contacts the substrate 122. For each magnet 142, this engagement with the ridge 128 and the substrate 122 restricts the movement of the magnet 142 in the axial direction. Simultaneously, for each magnet 142, the engagement of the inner surface 144 with the ridge 128 and / or other portions of the base, and the engagement of the outer surface 146 with the inner surface of the outer ring 160, restrict the movement of the magnet 142 in the radial direction. As a result, the magnet assembly 140 is fixedly positioned relative to the base 120.

[0044] like Figure 3 and Figure 6 As shown, a backplate 150 is mounted to a base 120 on the side opposite to the magnet assembly 140. The backplate 150 includes an annular plate 152 having a flat surface abutting the flat surface of the base plate 122. A plurality of arcuate recesses 154 extend from the inner surface of the annular plate 152. The recesses 154 are sized and configured to align with orifices 126 formed in the base 120. When the support 110 is assembled and the electromagnets 200 are mounted to the support 110, each electromagnet 200 extends through one of the orifices 126 formed in the base 120 and a corresponding recess 154 in the backplate 150. The backplate 150 provides additional strength and structural integrity to the base 120. Furthermore, each recess 154 in the backplate engages a portion of the corresponding electromagnet 200 to further restrict movement of the electromagnet relative to the support 110.

[0045] It should be understood that the disclosed support members are merely exemplary and should not be considered limiting. In some embodiments, portions of the support member may be integrally formed. In some embodiments, the size, number, and shape of the permanent magnets may vary. In some embodiments, the permanent magnets and / or electromagnets are coupled to the support member in different ways. These and other variations are contemplated and should be considered within the scope of this disclosure.

[0046] Now for reference Figures 8 to 11 Example embodiments of the electromagnet 200 according to various aspects of this disclosure will be described. Electromagnet 200. For example... Figure 10As best shown, the electromagnet 200 includes a pole piece 202 disposed at one end of a cylindrical core 204. In some embodiments, the pole piece 202 and the core 204 are formed of the same or different ferromagnetic materials. In some embodiments, the pole piece 202 and / or the core 204 are formed of iron or electrical steel. In some embodiments, the core 204 is not cylindrical. In this respect, the core 204 can have any suitable form, including cross-sections of different shapes, including but not limited to the profile of the pole piece 202. In some embodiments, the core has varying lengths and / or cross-sections. It should be understood that the core 204 can have any suitable construction / shape, and such variations should be considered within the scope of this disclosure.

[0047] The pole shoe 202 has a flat plate structure and is positioned at one end of the core 204, such that the centerline of the core is perpendicular to the pole shoe. For example... Figure 1 As shown, the pole shoe 202 has tapered sides configured to fit between and engage with the sides of adjacent magnets 142 when the electromagnet is mounted on the support 110. The upper and lower sides of the pole shoe 202 each have an arcuate profile, the dimensions and configuration of which are set between the outer ring 160 and the outer portion of the spline feature 124. In some embodiments, a fillet 206 provides a transition between the pole shoe 202 and the core 204, such as... Figure 10 As shown. In some embodiments, the pole shoe 202 is formed separately from the core 204 and is attached to the core using fasteners, welding, adhesives, or any other suitable fastening method or combination of fastening methods. In some embodiments, the pole shoe 202 and the core 204 are formed integrally. In some embodiments, the pole shoe has any suitable shape / profile.

[0048] refer to Figure 8 and Figure 9 The gasket 208 is positioned on the rear surface of the pole shoe 202 (i.e., the side from which the core 204 extends) and along the bottom edge of the pole shoe. Figure 6 As shown, when the pole shoe 202 and thus the electromagnet 200 are mounted to the support 110, the pole shoe 202 is coupled to the corresponding mounting feature 130 of the base 120. In the illustrated embodiment, a gasket 208 is sandwiched between the pole shoe 202 and the mounting feature 130, and a fastener 182 extends through the pole shoe 202 and the gasket 208 to thread-engage the mounting feature 130. It should be understood that the position of the electromagnet 200 relative to the support 110 in the axial direction can be changed by varying the thickness of the gasket 208. In some embodiments, more than one gasket is used for each electromagnet 200, and the position of the electromagnet 200 relative to the support 110 in the axial direction can be adjusted by varying the thickness and / or number of gaskets used. In some embodiments, the pole shoe 202 is secured to the mounting feature 130 using any suitable type, number, and / or combination of fasteners or coupling devices.

[0049] like Figure 6 , Figure 9 and Figure 11 As shown, the electromagnet 200 also includes a coil holder 210 mounted to the core 204. The coil holder 210 has a cylindrical first cylindrical portion 212 and a second cylindrical portion 214. An aperture 228 extends through the coil holder 210 and is sized to slidably receive the core 204.

[0050] The first cylindrical portion 212 is defined by a first flange 216 extending radially from one end of the first cylindrical portion and a second flange 218 extending radially from the other end of the first cylindrical portion. The first flange 216 and the second flange 218 have the same or similar diameters.

[0051] The second cylindrical portion 214 is defined by a second flange 218 extending radially from one end of the second cylindrical portion and a third flange 220 extending from the opposite end of the second cylindrical portion. The third flange 220 has a diameter smaller than that of the first flange 216 and the second flange 218.

[0052] Now for reference Figure 6 and Figure 9 Conductive wire 230 is wound around coil frame 210 to define coil 232. Second flange 218 separates first portion 234 of coil 232 from second portion 236 of coil 232. First portion 234 of coil 232 is disposed between first flange 216 and second flange 218. Second portion 236 of coil 232 is disposed between second flange 218 and third flange 220, and its diameter is smaller than the diameter of first portion 234 of coil 232.

[0053] like Figure 11 As shown, grooves 222 and 224 are formed in the first flange 216 and the second flange 218, respectively. Grooves 222 and 224 extend tangentially from the first cylindrical portion 212. The second flange 218 also includes a cut 226 extending radially inward from the outer edge of the flange.

[0054] refer to Figure 6 , Figure 9 and Figure 11 The wire 230 enters the coil holder 210 through the first slot 222 and is wound in layers around the first bobbin 212 to form a first portion 234 of the coil 232. The wire then passes through the second slot 224 and is wound in layers around the second bobbin 214 to form a second portion 236 of the coil. The tangential directions of the first and second slots limit the bending of the wire as it passes through slots 222 and 224. The wire exits the coil holder 210 through a cut 226.

[0055] like Figure 6 and Figure 8As best shown, a cylindrical first cap 240 extends from a first flange 216 to a second flange 218 and surrounds a first portion 234 of the coil. A cylindrical second cap 242 extends from the second flange 218 to a third flange 220.

[0056] Core 204 extends through aperture 228 of coil holder 210, which is secured to pole shoe 202 and core 204 by end cap 244 coupled to core 204. Pole shoe 202 and end cap 244 are fixedly positioned relative to each other and restrict axial movement of coil holder 210 relative to core 204 in both directions, thus keeping the coil holder mounted on the core. In the illustrated embodiment, end cap 244 is secured to core 204 by threaded fastener 246; however, it should be understood that any suitable construction can be used to secure the end cap to the core, and these variations should be considered within the scope of this disclosure.

[0057] like Figure 8 and Figure 9 As shown, the electromagnet 200 includes a pair of terminals 248 accessible from the outside of the electromagnet. Each terminal 248 is connected to one end of a wire 230 forming a coil 232 of the electromagnet 200, such that one terminal serves as an input and the other as an output. The terminals are configured to be connected to a power source that supplies current to the coil 232 to power the electromagnet.

[0058] Back Figure 1 and Figure 2 The disclosed support 110 and electromagnet 200 cooperate to provide an electromagnetic array 100, wherein permanent magnet 142 and pole shoe 202 cooperate to define a generally flat annular front. The support 110 has a compact profile in the axial direction, and the geometry of the coil frame 210 maximizes the number of turns of the wire 230 within the confined region. These features combine to provide a compact electromagnetic array 100 that generates increased magnetic flux output within a confined envelope.

[0059] Back Figure 12 The disclosed array 100 is suitable for use as a stator 60 for any number of electromagnetic devices 50. In some embodiments, the electromagnetic device 50 is an electromagnetic brake. In some embodiments, the electromagnetic brake is used for aircraft landing gear, and the array 100 is securely fixed to a shaft. In some embodiments, the electromagnetic device 50 is a motor, generator, or any other suitable device. In some embodiments, the surfaces of the array 100 are spaced apart from the corresponding rotors. In some embodiments, a pair of arrays 100 face each other, with rotors disposed between the arrays.

[0060] The specific embodiments described above in conjunction with the accompanying drawings (where like reference numerals refer to like elements) are intended to describe various embodiments of this disclosure and are not intended to represent only those embodiments. Each embodiment described in this disclosure is provided by way of example or illustration only and should not be construed as superior to or having an advantage over other embodiments. The illustrative examples provided herein are not intended to be exhaustive or to limit this disclosure to the precise forms disclosed. Similarly, any step described herein may be interchanged with other steps or combinations thereof to achieve the same or substantially similar results.

[0061] In the foregoing description, specific details have been set forth to provide a thorough understanding of representative embodiments of the present disclosure. However, it will be apparent to those skilled in the art that the embodiments disclosed herein can be practiced without showing all the specific details. In some cases, well-known process steps have not been described in detail to avoid unnecessarily obscuring various aspects of the disclosure. Furthermore, it should be understood that embodiments of the present disclosure may employ any combination of the features described herein. All such combinations or sub-combinations of features are within the scope of this disclosure.

[0062] This application may reference quantities and numbers. Unless otherwise stated, these quantities and numbers should not be considered limiting, but rather exemplary descriptions of possible quantities or numbers associated with this application. Furthermore, in this respect, the application may use the term "multiple" to refer to quantities or numbers. In this respect, the term "multiple" means any number greater than one, such as two, three, four, five, etc. The terms "approximately," "approximately," "close to," etc., mean plus or minus 5% of the stated value. For the purposes of this disclosure, the phrase "at least one of A, B, and C" means, for example, (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C), and includes all further possible permutations when more than three elements are listed.

[0063] It should be noted that, for the purposes of this disclosure, terms such as “upper,” “lower,” “vertical,” “horizontal,” “front,” “back,” “inner,” “outer,” “front,” and “rear” should be interpreted as descriptive rather than limiting the scope of the claimed subject matter. Furthermore, the use of “comprising,” “including,” or “having,” and variations thereof herein is intended to cover the items listed thereafter and their equivalents, as well as additional items. Unless otherwise limited, the terms “connection,” “link,” and “installation,” and variations thereof, as used herein, are used broadly and cover both direct and indirect connections, links, and installations.

[0064] Throughout this specification, terms used in this field may be employed. These terms should have their ordinary meaning in the field of their origin, unless otherwise specifically defined herein or the context in which they are used clearly indicates otherwise.

[0065] The figures in the accompanying drawings are not drawn to scale. Similar elements are generally indicated by similar reference numerals in the drawings. For the purposes of this disclosure, identical or similar elements may bear the same reference numerals. Furthermore, the presence of reference numerals or letters in the drawings should not be considered limiting, even if such numerals or letters are indicated in the claims.

[0066] The principles, representative embodiments, and modes of operation of this disclosure have been described above. However, the aspects of this disclosure intended to be protected should not be construed as limited to the specific embodiments disclosed. Furthermore, the embodiments described herein should be considered illustrative rather than restrictive. It should be understood that variations and modifications, and equivalents, can be made by those skilled in the art without departing from the spirit of this disclosure. Therefore, it is expressly intended that all such variations, modifications, and equivalents fall within the spirit and scope of the claimed disclosure.

Claims

1. An electromagnet, comprising: core; The coil holder has the following features: A first cylindrical portion, the first cylindrical portion being defined by a first flange extending radially from a first end of the first cylindrical portion and a second flange extending radially from a second end of the first cylindrical portion; The second cylindrical portion is defined by a second flange at a first end of the second cylindrical portion and a third flange extending radially from the second end of the second cylindrical portion, wherein the diameter of the first flange is larger than the diameter of the third flange. as well as An orifice extending through the first cylindrical portion and the second cylindrical portion, wherein the core is disposed within the orifice; A wire, the wire being wound around the first cylindrical portion to define a first portion of the coil, and wound around the second cylindrical portion to define a second portion of the coil; as well as A power source that provides current through the wires.

2. The electromagnet according to claim 1 further includes a pole piece disposed at one end of the core.

3. The electromagnet according to claim 1, wherein, The diameter of the first portion of the coil is larger than the diameter of the second portion of the coil.

4. The electromagnet according to claim 1, wherein, A groove is formed in the second flange, the groove extending outward from the first cylindrical portion, wherein the wire extends through the groove between the first coil portion and the second coil portion.

5. The electromagnet according to claim 4, wherein, The groove is tangent to the first cylindrical section.

6. An electromagnetic array, comprising: Annular support component; as well as The electromagnet according to claim 2, wherein the pole shoe is connected to the annular support.

7. The electromagnetic array according to claim 6 further includes a gasket disposed between the pole shoe and the annular support.

8. The electromagnetic array according to claim 6, wherein, The annular support includes an internal spline surface.

9. The electromagnetic array according to claim 8, wherein, The annular support also includes an annular base and a plurality of permanent magnets connected to the base.

10. The electromagnetic array according to claim 9, wherein, Each of the permanent magnets includes a recess and / or a cutout, and the annular base includes a ridge extending radially into the recess and / or the cutout of each permanent magnet.

11. The electromagnetic array according to claim 10, wherein, The permanent magnet and the pole shoe cooperate to define a flat surface.

12. An electromagnetic array, comprising: Annular support component; as well as Multiple electromagnets according to claim 2, wherein the pole piece of each electromagnet is connected to the annular support.

13. The electromagnetic array according to claim 12, wherein, The electromagnets among the plurality of electromagnets are evenly spaced around the annular support.

14. The electromagnetic array according to claim 13, wherein, A gasket is provided between each pole shoe and the annular support.

15. An electromagnetic brake, comprising a stator, said stator comprising the electromagnetic array of claim 12.

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