Radial actuator for magnetic radial bearing module

Abstract

[Radial actuator for magnetic radial bearing module] This radial actuator 1 comprises an arrangement of coils 2 disposed around a central axis XX' and each formed by bundles of laminations 3 and by winding wire electrically insulated from said bundles of laminations 3. The radial actuator 1 further comprises two separate opposing flanges 5 comprising an electrically insulating material and disposed on either side of the bundles of laminations 3 of at least one of said coils 2, the winding wire of said coil 2 being wound around the two flanges 5 and in contact with said flanges. Figure for the abbreviation: [Fig 4]

Description

Title of the invention: Radial actuator for magnetic radial bearing module Technical field of the invention

[0001] The present invention relates to magnetic actuator modules, in particular for magnetic radial bearings, and in particular to solutions enabling different configurations of radial actuator modules to be made, whether in terms of diameter or active face length.

[0002] The present invention aims to constitute a modular radial actuator module in which each quadrant of coils can be made independently of the others, and capable of adapting to several coil geometries: number of horns, height and insulation of the coil lamination pack, the cross-section of the wires and cables used, type of interconnection, etc. Prior art

[0003] A magnetic actuator module of a system, such as an industrial machine, classically comprises a position sensor and one or more magnetic actuators.

[0004] Two methods are known for manufacturing and mounting the coils on the sheet metal bundle to form a radial actuator that integrates into a magnetic bearing module: rolling the coils upstream on a tool, followed by mounting it by insulating the sheet metal bundle with an insulating material; or rolling the coils on frames specific to a horn size and then mounting the assembly on the sheet metal bundle.

[0005] The upstream coil rolling method has the disadvantage of requiring a tool specific to a sheet pack size, which imposes a standardization of sheet pack dimensions or a costly multiplication of tools.

[0006] In addition, the additional insulation and assembly are particularly time-consuming operations.

[0007] The coil rolling method also poses the disadvantage of standardizing dimensions since the carcass is specific to a size of sheet metal bundle.

[0008] In both cases, the shape of the sheet metal bundle is constrained by these manufacturing operations, its limits being in particular in its size to ensure the insertion of the wire windings of the coils onto the sheet metal bundle. Summary of the invention

[0009] The invention aims to overcome at least some of the aforementioned drawbacks.

[0010] In view of the foregoing, the invention relates to a radial actuator for a module of a magnetic radial bearing, comprising an arrangement of coils disposed around a central axis and each formed by bundles of laminations and by winding wire electrically insulated from said bundles of laminations, the radial actuator further comprising two separate opposing flanges which comprise an electrically insulating material and which are disposed on either side of the bundles of laminations of at least one of said coils, the winding wire of said coil being wound around the two flanges and coming into contact with said flanges.

[0011] With this flange design, it is possible to easily adjust the height of the sheet metal bundle on the associated coil to the desired dimension. Furthermore, the wire winding operations can be easily carried out directly on the flanges.

[0012] Preferably, the two flanges are radially open on the side of the central axis of the position sensor and the sheet metal bundles protrude towards said central axis relative to the flanges.

[0013] This allows the length of the sheet metal bundle to be modulated according to the need, depending on the load capacity requirement of the associated magnetic bearing module.

[0014] For example, the flanges axially clamp the sheet metal bundles of said coil. Alternatively, the flanges can clamp the sheet metal bundles of said coil circumferentially.

[0015] According to a first embodiment, the two flanges are axially spaced apart from each other, the radial actuator further comprising two insulating elements comprising an electrically insulating material, interposed axially between the flanges, i.e. parallel to the central axis, and arranged circumferentially on either side of the sheet metal bundles of said coil.

[0016] Each insulating element may comprise an electrically insulating paper, an electrically insulating resin, and / or a sprayed powder agglomerated in the gap.

[0017] According to a second embodiment, the flanges come axially in contact with each other.

[0018] The flanges can then each further include a notch on the side of the sheet metal bundles of said coil to locally increase the circumferential distance between said sheet metal bundle and the winding wire.

[0019] Advantageously, at least one of said coils has a trapezoidal or pyramidal shape.

[0020] The radial actuator may further provide that the arrangement of coils forms quadrants of two or more coils, and two flanges are arranged on either side of all the coils of the same quadrant.

[0021] The invention also relates to a magnetic bearing module comprising a magnetic bearing as described above. Brief description of the figures

[0022] The invention will be better understood upon detailed examination of several embodiments taken by way of non-limiting example and illustrated by the accompanying drawings, in which:

[0023] [Fig. 1] represents a partial perspective view of a modular radial actuator according to a first embodiment of the invention having two-coil quadrants with independent coils wound on single-horn flanges.

[0024] [Fig.2] represents a partial perspective view of a modular radial actuator according to a second embodiment of the invention, featuring quadrants with two coils with a single flange comprising two horns.

[0025] [Fig.3] represents another perspective view of a modular radial actuator according to a third embodiment of the invention with modulation of the inner diameter of the sheet metal bundle.

[0026] [Fig.4] represents another perspective view of a modular radial actuator according to a fourth embodiment of the invention with modulation of the height of the sheet metal bundle.

[0027] [Fig.5] represents another perspective view of a modular radial actuator according to a fifth embodiment of the invention with modulation of the inner diameter and height of the sheet metal bundle.

[0028] [Fig.6] represents a cross-sectional view at the level of a coil of the modular radial bearing of [Fig.3].

[0029] [Fig.7] represents another cross-sectional view at the level of a coil of the modular radial bearing of [Fig.4].

[0030] [Fig.8] represents a cross-sectional view of [Fig.5]. Detailed description of the invention

[0031] Fig. 1 illustrates the radial actuator for magnetic radial bearing module 1 according to a first embodiment of the invention.

[0032] The radial actuator 1 comprises an arrangement of coils 2 arranged around a central axis XX' and each formed by bundles of sheets 3 and by winding wire (not shown) which is electrically insulated from said bundles of sheets 3.

[0033] The arrangement of coils 2 forms a concentric ring of coils 2 around the central axis XX', dedicated to accommodate a mechanical shaft in its center along said central axis XX', for a rotating machine, in particular an industrial one.

[0034] The radial actuator 1 further comprises, for each coil 2, two flanges 5 distinct opposites which are arranged on either side of the bundles of sheets 3 of said coil 2, the winding wire surrounding the two flanges 5.

[0035] The flanges 5 comprise an electrically insulating material.

[0036] The flanges 5 are intended to receive winding wire on their outer surface, particularly in copper, surrounding the two opposing flanges 5 to form a coil 2. The winding wire is wound around the two flanges 5 and comes into contact with said flanges. The winding wire is not wound directly around the bundles of laminations 3.

[0037] In the illustrated embodiment, the flanges 5 are identical to each other and have a U-shaped cross-section.

[0038] The flanges 5 are symmetrical with respect to a median radial plane of the coil.

[0039] In the illustrated embodiment, the flanges 5 are axially supported against each other and define a channel within which the bundle of sheets 3 of the associated coil extends.

[0040] In the illustrated embodiment, the two flanges 5 are radially open on the inner side, i.e. towards the central axis XX', and the sheet metal bundles 3 extend in projection on the side of said central axis XX' relative to the flanges 2.

[0041] For example, the flanges 5 axially enclose the bundles of sheets 3 of the associated coil.

[0042] The open shape of the flanges 5 does not fully encompass the radial length of the horns of the sheet metal pack 3 of the associated coil, which allows the length of the horn formed by the sheet metal pack 3 to be modulated according to the need, which will allow the number of coil carcass references 2 to be reduced and the internal diameter of the radial actuator 1 to be modulated.

[0043] It is also possible to modulate the height of the sheet metal bundle 3 of the associated coil taking into account the realization of the flanges 5 in the form of two separate pieces.

[0044] In [Fig. 1], the radial actuator 1 is such that each coil 2 belongs to a unit quadrant, i.e. comprising a single coil 2.

[0045] In the second embodiment illustrated by [Fig.2], the radial actuator 1 can alternatively be such that the arrangement of coils 2 forms quadrants 4 of several coils 2, for example two or more coils 2, for example three coils 2, and in this case two coils 2 on [Fig.2], and that the two flanges 5 are arranged on either side of all the coils 2 of the same quadrant 4.

[0046] This allows the flanges 5 to be shared, and further increases the modularity of the design of the radial actuator 1.

[0047] In this design, each flange 5 is adapted to the shape of several successive packs of sheets 3, and connects all the coils 2 of the same quadrant 4.

[0048] The two opposite flanges 5 are always arranged on each side of the corresponding sheet metal bundles 3 of the quadrant 4 and allow the sheet metal bundles 3 to be isolated from the winding wires during their automatic in situ winding.

[0049] The advantage of working in quadrant 4 is that it is not dependent on the expansion global radial actuator 1 and to produce a part made of electrically insulating material, for example plastic, which is smaller, therefore more economical to manufacture.

[0050] The presence of two opposing flanges 5 instead of a single one encompassing the entire sheet metal package also allows that the thermal expansion stresses are reduced in the two flanges 5 because they are not propagated from and towards the two flanges 5.

[0051] Figure 3 illustrates a third embodiment in which the sheet metal bundles 3 can be designed with a longer shape towards the center of the radial actuator 1 for a given pair of flanges 5, insofar as the flanges are radially open on the inner side. It is thus possible to modulate the length of the horn of the sheet metal bundle 3 and the diameter of the active area, particularly according to the load-carrying capacity requirements of the magnetic bearing module.

[0052] Fig. 4 illustrates a fourth embodiment in which the bundles of sheets 3 of each coil have a greater height, which is possible for the same shape of flanges 5, since they are formed by two separate pieces, i.e. can be separated and placed independently of each other.

[0053] Thus, as illustrated by Figures 1, 2 and 3, the two flanges 5 can be joined and pressed against each other, which avoids having a gap separating the flanges 5, and therefore the need to add electrical insulation between the winding wire in the contact area of ​​the two flanges 5.

[0054] In the first, second and third embodiments, the two flanges 5 enclosing the bundle of sheets 3 are for example fitted together to perform this overlap and ensure the continuity of insulation.

[0055] This solution involves a different set or parts depending on the height of the sheet metal bundle 3.

[0056] Alternatively, in the first, second and third embodiments, when the two flanges 5 are mounted without being supported against each other or sealed tightly, the flanges 5 are separated by ambient gas, for example air, which is a relatively weak electrical insulator.

[0057] In the case of the use of ambient air between the two flanges 5, the continuity of electrical insulation between the winding wires covering the flanges 5 and the lamination packs 3 can be ensured by means of a design in which the flanges 5 each have a notch 8 visible in Figures 3, 6 and 7, which is adapted to sufficiently increase the distance between the lamination pack 3 and its winding wire, in particular the air distance.

[0058] Indeed, industrial machine standards impose electrical insulation distances between wound elements and metallic faces, in this case the sheet metal of the sheet metal packs 3.

[0059] With a classic one-piece flange, i.e. extending circumferentially all around the sheet metal bundle 3, the continuity of insulation is guaranteed continuously all around the sheet metal bundle 3.

[0060] Conversely, in the case of an open part or one separated into two flanges 5, the continuity of electrical insulation can be guaranteed by an insulating foreign body or by respecting an imposed distance in the air.

[0061] This solution avoids covering the electrically exposed surfaces of the sheet metal pack 3, and the addition of external components as insulating elements 7, by creating air insulation by moving the external surfaces of the flanges 5 supporting the passage of the winding wire sufficiently far from the metallic surfaces of the sheet metal pack 3 to comply with the distances according to the standards used.

[0062] For example, it is recommended to make a slot 8 such that the air distance between the pack of sheets 3 and its winding wire is at least two and a half millimeters, to ensure electrical insulation thanks to said ambient gas.

[0063] Thus, it can be foreseen that the ambient gas includes air and that the distance between the pack of sheets 3 and its winding wire is greater than or substantially equal to two and a half millimeters, to achieve sufficient electrical insulation for the operation of the radial actuator 1.

[0064] In the fourth and fifth embodiments illustrated by Figures 4, 5 and 7, the two flanges 5 are axially spaced from each other, the radial actuator 1 further comprising two insulating elements 7 comprising an electrically insulating material interposed axially between the flanges 5 and arranged circumferentially on either side of the sheet metal bundles 3 of said coil 2.

[0065] With the two flanges 5 separated, a gap 6 separates said flanges 5 and may include said insulating elements 7, as illustrated in Figures 4 to 5 and 7. The winding wire is wound around the two flanges 5 and the insulating elements 7, and comes into contact with said flanges and said insulating elements. The winding wire is not wound directly around the bundles of laminations 3.

[0066] The insulating elements 7 are chosen to have a particularly high dielectric coefficient.

[0067] Advantageously, the insulating elements 7 comprise an electrically insulating paper 9, an electrically insulating resin, and / or a sprayed powder agglomerated in the gap 6.

[0068] As detailed in Figures 6 and 7, illustrating the fifth embodiment, the slot 8 of the first, second and third embodiments can also be used in the fourth and fifth embodiments since it can serve as a notch to hold the insulating elements 9 in position, in particular when it is an electrically insulating paper in the form of a strip.

[0069] Thanks to such a notch function of the slot 8, there is no need to mechanically constrain the insulating elements 7 to maintain their own shape throughout the life of the radial actuator 1, because the insulating elements 7 are inserted on both sides in the notch 8 of each flange 5, and can move freely between the two from one to the other, which allows a lighter design compared to a design with attached retaining means which result in excessively constrained and / or hyperstatic retention.

[0070] The slotted notch 8 therefore makes it possible to offer greater durability of the insulating elements 7 and of the radial actuator 1.

[0071] Moreover, this unconstrained design of the insulating elements 7 facilitates their placement on either side of one of the sheet metal bundles 3, since it is enough to insert them into the notches 8, which facilitates the manufacture of the radial actuator 1.

[0072] The addition of insulating elements 7, in particular thin ones, combined with an overlap of the flanges 5 to guarantee the insulation distance, is a solution suitable for all heights of sheet metal bundles 3, even if its implementation requires a specific length of insulation for each version of sheet metal bundle 3.

[0073] As illustrated by [Fig.8], the fifth embodiment may further provide spaces 10 formed by a spacer 11 attached to or formed by a flange 5, which allow this flange 5 to be spaced apart from the stack of sheets 3, to ensure that the winding wires are arranged at a distance allowing electrical insulation by the ambient gas, in particular the air around said stack of sheets 3.

[0074] The spacer then linked a toothed shape to allow a gap including a maximum of air.

[0075] One of the most economical alternatives is to substitute the addition of thin insulating elements 9 with prior protection of the sheet metal bundle 3 on the relevant faces of the sheet metal bundle 3, namely those electrically exposed, by depositing a resin in the form of a thermally agglomerated powder.

[0076] Advantageously, in any embodiment, at least one coil 2 has a trapezoidal or pyramidal shape.

[0077] These shapes, formed by bundles of sheet metal 3 in the shape of blocks with non-parallel faces directed towards the center of the radial actuator 1, are made possible by the manufacturing process integrating the two distinct flanges 5 around the bundles of sheet metal 3.

[0078] The substantially pyramidal or trapezoidal shape optimizes the bottom filling of a coil 2, which is impossible in conventional manufacturing techniques due to mechanical interference between the coils 2 during their insertions.

[0079] The invention also relates to a magnetic bearing module comprising a magnetic bearing and a radial actuator 1 as described above in which the coils 2 have winding wire wrapped around flanges 5.

[0080] The invention also relates to a method of manufacturing such a magnetic bearing module, in which the two flanges 5 are placed on either side of one of the stacks of sheets 3, then an electrically insulating resin and / or agglomerated sprayed powder is added in the gap 6, then a so-called needle rolling is carried out allowing the winding of winding wire around the two flanges 5 and of said resin and / or powder so as to form a coil 2 of which said winding wire is both wound around the two flanges 5 and electrically insulated from any stack of sheets 3 by said flanges 5 and by said electrically insulating resin, and / or agglomerated sprayed powder.

Claims

Demands

1. Radial actuator for magnetic radial bearing module (1), comprising an arrangement of coils (2) disposed around a central axis (XX') and each formed by bundles of laminations (3) and by winding wire and electrically insulated from said bundles of laminations (3), characterized in that the radial actuator (1) further comprises two distinct opposing flanges (5) which comprise an electrically insulating material and which are disposed on either side of the bundles of laminations (3) of at least one of said coils (2), the winding wire of said coil (2) being wound around the two flanges (5) and coming into contact with said flanges.

2. Radial actuator (1) according to claim 1, wherein the two flanges (5) are radially open on the side of the central axis (XX') and the sheet metal bundles (3) project outwards towards said central axis (XX') relative to the flanges (5).

3. Radial actuator (1) according to claim 1 or 2, wherein the flanges (5) axially enclose the sheet metal bundles (3) of said coil (2).

4. Radial actuator (1) according to any one of claims 1 to 3, wherein the two flanges (5) are axially spaced apart from each other, the radial actuator (1) further comprising two insulating elements (7) comprising an electrically insulating material, interposed axially between the flanges (5) and arranged circumferentially on either side of the sheet metal bundles (3) of said coil (2).

5. Radial actuator (1) according to claim 4, wherein the insulating elements (7) comprise an electrically insulating paper (9), an electrically insulating resin, and / or a sprayed powder agglomerated in the gap (6).

6. Radial actuator (1) according to any one of claims 1 to 3, wherein the flanges (5) axially bear against each other.

7. Radial actuator (1) according to claim 6, wherein the flanges (5) each have a slot (8) on the side of the sheet metal bundles (3) of said coil (2) to locally increase the circumferential distance between said sheet metal bundle (3) and the winding wire.

8. Radial actuator (1) according to any one of claims 1 to 7, wherein at least one of said coils (2) has a trapezoidal shape or pyramidal.

9. Radial actuator (1) according to any one of claims 1 to 8, wherein the arrangement of coils (2) forms quadrants (4) of two or more coils (2), and two flanges (5) are arranged on either side of all the coils (2) of the same quadrant (4).

10. Magnetic bearing module comprising a magnetic bearing and a radial actuator (1) according to any one of claims 1 to 9.

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