Grounding ring, rolling bearing comprising such a ring, and method for manufacturing such a ring

Abstract

The invention relates to a grounding ring (10) intended to be mounted between a stationary element (11) and a rotary element (12), comprising a first armature (20), a plurality of strips (30) and a fastening member (40) for fastening the strips to the first armature, the first armature and the strips being capable of conducting an electric current between the stationary element and the rotary element.

Description

[0001] Electrical balancing ring, rolling bearing comprising such a ring, and method of manufacturing such a ring

[0002] TECHNICAL FIELD

[0003] The present invention relates to an electrical balancing ring or grounding ring, used to transmit electrical charges or an electric current between a fixed element and a rotating element mobile in rotation relative to the fixed element around an axis of rotation.

[0004] Typically, the ring is used to conduct electrical charges between a casing and a shaft of a machine, or more particularly between a stator and a rotor of an electrical machine.

[0005] STATE OF PRIOR ART

[0006] The invention thus relates to an electrical balancing ring comprising a first, annular, rigid armature, mounted integrally on one of the fixed element and the rotating element.

[0007] Document EP1872463 shows such an electrical balancing ring comprising a brush consisting of electrically conductive filaments arranged radially towards the internal rotating shaft and clamped by annular plates.

[0008] However, positioning and maintaining these filaments is complex and costly. There is a risk of filaments becoming detached, particularly during shaft rotation or when changing the direction of rotation of the shaft.

[0009] Document US 2020 / 0295634 shows such an electrical balancing ring which comprises an annular disc-shaped discharge element, made of an electrically conductive material. The discharge element has an annular body of large external diameter for its fixation between two armatures and the centering of this disc-shaped discharge element. Furthermore, the discharge element comprises radial slots to improve the flexibility of this discharge element and the contact thereof with the rotating shaft.

[0010] However, this discharge element is expensive to manufacture due to the large amount of material at its external diameter required to center it in the ring for correct electrical contact around its circumference.

[0011] STATEMENT OF THE INVENTION

[0012] A first object of the present invention is to provide an electrical balancing ring which is less expensive to produce and with better electrical contact with the rotating element.

[0013] For this purpose, the electrical balancing ring comprises: a plurality of lamellae positioned on the first armature around the axis of rotation, made of an elastic material, each lamella extending between a first end in contact with the first armature, and a second end in contact with the other element among the fixed element and the rotating element, a fixing member adapted to fix the lamellae to the first armature, and in which the first armature and the lamellae are capable of conducting an electric current between the fixed element and the rotating element, and the lamellae are separated from each other by intermediate spaces.

[0014] Thanks to these arrangements, the lamellae of the electric ring are independent and separate elements from each other, without an annular part connecting the lamellae to an external diameter.

[0015] The ring then comprises less material and is less expensive to produce. In addition, these lamellae are substantially flat and reliably fixed and held to the first frame. These lamellae are not at risk of detaching from the first frame.

[0016] In various embodiments of this product, one and / or the other of the following provisions may optionally be used in addition.

[0017] In one aspect, the slats have a rectangular, trapezoidal, or angular sector shape.

[0018] In one aspect, the plurality of slats have shapes or lengths in a radial direction that are different.

[0019] In one aspect, the lamellae are formed from a PTFE material containing at least one electrically conductive filler, such as carbon and / or graphite.

[0020] In one aspect, the lamellae have at least one contact surface covered with a coating capable of conducting an electric current, and made of a material containing silver, copper, aluminum, carbon, graphene or graphite.

[0021] In one aspect, the slats have a wear reserve or embossing.

[0022] According to one aspect, the fixing member comprises at least one second, annular, rigid frame, mounted integral with the first frame so as to fix the strips between the first frame and the second frame by pinching.

[0023] According to one aspect, the second armature is capable of conducting an electric current.

[0024] According to one aspect, the fixing member comprises at least one overmolding of the slats on the first frame.

[0025] In one aspect, the fastener is made of a material suitable for overmolding, such as an elastomer, an NBR elastomer, an HNBR elastomer, a silicone, a thermoplastic, a polymer or a resin.

[0026] According to one aspect, the fixing member is made of a material containing at least one electrically conductive filler, such as carbon and / or graphite.

[0027] According to one aspect of the ring: the first frame comprises recesses, and the overmolding material of the fixing member passes through said recesses to fix the lamellae to the first frame.

[0028] According to one aspect of the ring: the first armature is curved in a direction of the axis of rotation to tilt the lamellae by contact in said direction.

[0029] According to one aspect of the ring: the lamellae are formed from an annular membrane in the shape of an annular disc with radially extending tabs, and the membrane being fixed to the first frame by the fixing member, and the membrane is cut over an annular portion of its internal diameter to separate tabs from the membrane and form the lamellae separated from each other by intermediate spaces.

[0030] A second object of the present invention is to provide a rolling bearing comprising an electrical balancing ring according to the preceding characteristics, and rolling bodies arranged in a rolling space to allow relative rotation of the rotating element with respect to the fixed element around the axis of rotation.

[0031] A third object of the present invention is to provide a method of manufacturing an electrical balancing ring, said ring being intended to be mounted between a fixed element and a rotating element movable in rotation relative to the fixed element around an axis of rotation, said method comprising the steps of:

[0032] - a first rigid annular armature is provided, intended to be mounted securely on one of the fixed element and the rotating element, the first armature being capable of conducting an electric current,

[0033] - an annular membrane in the form of an annular disc with radially extending tabs is provided, the membrane being made of an elastic material, and capable of conducting an electric current,

[0034] - the membrane is fixed to the first frame by a fixing member, and

[0035] - an annular portion of the internal diameter of the membrane is cut to separate the tabs and form strips separated from each other by intermediate spaces.

[0036] In various embodiments of this method, one and / or the other of the following arrangements may optionally be used in addition.

[0037] According to one aspect, the membrane is formed from an annular disc in which radial slots are cut extending from an outer diameter to an inner diameter, without opening onto the inner diameter to maintain a continuous annular portion at the inner diameter, said slots forming the tabs.

[0038] According to one aspect, the membrane is positioned relative to the first frame before fixing this membrane, by an internal diameter of said membrane.

[0039] According to one aspect, the cut of the annular portion of the internal diameter of the membrane is a cut coaxial with the first frame. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Other characteristics and advantages of the product will appear during the following description of at least one of its embodiments, given as a non-limiting example, with reference to the attached drawings.

[0041] On the drawings:

[0042] - Figure 1 is a sectional view of a first embodiment of an electrical balancing ring according to the present disclosure;

[0043] - figure 2 is a sectional and perspective view of the ring of figure 1, the first frame being shown transparent;

[0044] - Figure 3 is a sectional view of a second embodiment of an electrical balancing ring according to the present disclosure;

[0045] - figure 4 is a sectional and perspective view of the ring of figure 3, the first frame being shown transparent;

[0046] - Figure 5 is a sectional view of a rolling bearing incorporating an electrical balancing ring of the type of Figure 1 or Figure 3;

[0047] - Figure 6A is a view of a membrane blank;

[0048] - Figure 6B is a membrane made from the blank of Figure 6A and used in a method of manufacturing an electrical balancing ring;

[0049] - Figure 7 shows steps A, B, C, D and E of a method of manufacturing the ring of the first embodiment of Figure 1 and Figure 2; and

[0050] - Figure 8 shows steps A, B, C, and D of a method of manufacturing the ring of the first embodiment of Figure 3 and Figure 4.

[0051] In the various figures, the same numerical references designate identical or similar elements. DETAILED DESCRIPTION

[0052] Figures 1 to 4 show two embodiments of an electrical balancing ring 10 which is intended to be mounted between a fixed element 11 and a rotating element 12 movable in rotation relative to the fixed element around an axis of rotation AX.

[0053] Ring 10 includes:

[0054] - a first frame 20, of annular type around the axis of rotation, which is rigid and which is mounted integral with one of the fixed element 11 and the rotating element 12,

[0055] - a plurality of slats 30 positioned on the first frame around the axis of rotation, made of an elastic material, and a fixing member 40 adapted to fix the slats 30 to the first frame.

[0056] The first armature 20 and the strips 30 are capable of conducting an electric current, in particular so that an electric current can flow between the fixed element 11 and the rotating element 12, or vice versa.

[0057] The slats 30 extend between a first end 31 in contact with the first frame 20, and a second end 32 in contact with the other element among the fixed element and the rotating element.

[0058] The slats 30 comprise a body 33 between the first end 31 and the second end 32.

[0059] In particular, the fixed element 11 may be an external element, i.e. the furthest from the axis of rotation AX, i.e. located around the rotating element 12 which is then an internal element. This is the case of using a rotating element 12 which is a rotating shaft (figure 1).

[0060] Conversely, the fixed element 11 can be an internal element, i.e. closest to the axis of rotation AX, i.e. located inside the rotating element which is then an external element.

[0061] For the sake of simplification of the present description, it will now be considered that the first armature 20 is connected to the external fixed element 11, and that the second end 32 is in contact with the other element, i.e. the internal rotating element 12, but of course the other use is also suitable for the present disclosure.

[0062] The slats 30 have a contact surface 34 configured to slide in contact on a sliding surface 14 of the other element, i.e. the rotating element 12.

[0063] The electrical balancing ring 10 can therefore conduct an electric current from the rotating element 12 to the lamellae 30 by the contact of the contact surface 34 at the second end 32 of the lamellae 30, then by the body 33 of the lamellae 30 to the first armature 20 in contact with the first end 31 of the lamellae 30, then by the first armature 20 to the fixed element 11 thanks to the contact between this first armature 20 and the fixed element 11. The electrical conduction can also take the reverse path. The electrical conductivity of the electrical balancing ring 10 is thus high, and makes it possible to efficiently evacuate electrical charges.

[0064] The first frame 20 is called “rigid” because it is formed from a material of much greater rigidity (more than 10 times more) than the strips made of “elastic” material.

[0065] For example, the first frame is made of a metallic material, such as steel. For example, the slats are made of a rubber, elastomer, thermoplastic (TP) or polytetrafluoroethylene (PTFE) type material.

[0066] The slats 30 may have a rectangular shape, a trapezoidal shape, or an angular sector shape.

[0067] The slats 30 are elements independent of each other. These slats are fixed to the first frame 20 by the fixing member 40. They are thus fixed to each other by means of the first frame 20 and the fixing member 40, but they are all separated from each other. In other words, there is a gap or intermediate space between said slats 30: A gap or intermediate space 37 separates two successive slats in a direction of the circumference of the ring 10.

[0068] The structure of the lamellae 30 of the ring 10 is different from a brush in which the filaments touch each other and for which their relative positions are not easily determined, which causes difficulties in fixing and which can cause risks of detachment of the filaments, in particular during rotation of the shaft or during a change in the direction of rotation of the shaft.

[0069] The structure of the lamellae 30 of the ring 10 is also different from an annular disc which has at least one continuous annular portion over an outer diameter allowing said annular disc to be positioned relative to the first armature. However, such an annular disc contains more material, which is expensive.

[0070] The structure of the lamellae 30 of the ring 10 according to the present disclosure is more complex to produce. However, it allows for better fixing of the lamellae 30 than for fixing the filaments of the brushes. It also allows for reducing the cost of the conductive annular discs. In addition, this structure of independent lamellae 30 offers advantages in terms of modularity and construction.

[0071] The slats 30 are separated from each other by intermediate spaces 37 between said slats. The slats 30 can therefore form angular sectors distributed over the circumference of the ring 10. These intermediate spaces 37 thus extend from the first end 31 to the second end 32 of the slats 30.

[0072] Thanks to these independent lamellas 30, the lamellas 30 are more flexible than an annular disc. The radial force is reduced. In addition, a smaller variation in the radial force is obtained in cases of circularity defect of the rotating element 12 and / or coaxiality defect between the fixed element 11 and the rotating element 12. The lamellas 30 more easily maintain electrical contact with the sliding surface 14 of the rotating element 12. The electrical conductivity is increased and this electrical conductivity is more stable in operation.

[0073] The lamellae 30 of the plurality of lamellae may have shapes that are different from one another. Indeed, thanks to their independence, it is possible to have lamellae 30 of different shapes depending on the direction of the circumference of the ring 10.

[0074] The slats 30 of the plurality of slats may have lengths that are different from one another. Thus, the slats 30 may adapt more easily to the rotating element 12. In particular, if the rotating element 12 has radial positions that vary during its rotation, the slats 30 are less likely to lose contact with the rotating element 12 during rotation. At least one or more slats remain in electrical contact with the rotating element 12.

[0075] The slats 30 are for example formed from a material of the polytetrafluoroethylene (PTFE) type.

[0076] The material of the lamellae 30 may contain at least one electrically conductive filler (capable of conducting electricity). This electrically conductive filler is, for example, based on carbon or graphite.

[0077] The slats 30 have a contact surface 34 which is for example covered with a coating capable of conducting an electric current. The coating is for example made of a material containing silver, copper, aluminum, carbon, graphene or graphite.

[0078] The contact surface 34 is on a first face 35 of the slats 30, which comes into contact with the sliding surface 14 of the rotating element 12.

[0079] The slats 30 may have a wear reserve. This wear reserve may be on the first face 35 of the slats 30, and in particular at the contact surface 34 in contact with the rotating element 12. The wear reserve is thus located at the second end 32 of the slats 30.

[0080] This wear reserve has a thickness greater than the thickness of the body 33 of the slats 30. For example, this thickness of the wear reserve is twice the thickness of the body 33 of the slats 30.

[0081] The body 33 of the slats 30 may comprise undulations (embossing) configured to adjust a desired value of the rigidity or flexibility of said body of the slats. These undulations are for example located at one or more positions between the first end and the second end.

[0082] The body 33 of the slats 30 may comprise one or more thickness restrictions, for example located at one or more positions between the first end and the second end. This or these restrictions are for example a reduction in thickness on a circumference or a portion of circumference of the slats. This or these thickness restrictions may also be used to adjust a desired value of the rigidity or flexibility of the slats 30.

[0083] According to a variant, the first armature 20 may have an internal end 23 curved in the direction X of the axis of rotation AX. Thus, the slats 30 more easily take a desired curved shape, and determined by calculation and / or tests. Indeed, this curved shape, the thickness, and the material of the slats 30 determine a radial force that the slats 30 exert concentrically towards the axis of rotation and on the rotating element 12. This radial force determines the good contact of the slats 30 on the rotating element 12, and therefore the electrical conductivity of the ring 10 and its capacity to maintain this conductivity in operation, i.e. during the rotation of the rotating element 12 and during the operating period.

[0084] According to a first embodiment of the ring 10, as presented in FIG. 1 and FIG. 2, the fixing member 40 of the slats 30 comprises a second annular-type frame 40i around the axis of rotation, which is rigid and which is mounted integral with the first frame 20.

[0085] The second frame 40i is adapted to pinch and fix the slats 30 between the first frame 20 and the second frame 40i. In other words, the slats 30 are fixed by pinching between the first frame and the second frame, for example at the time of fixing the second frame 40i on the first frame 20.

[0086] The second frame 40i is for example mounted securely inside the first frame 20, possibly by fitting or by crimping.

[0087] According to the embodiment shown, the first frame 20 and the second frame 40i have an L shape nested within each other. Each of these frames 20, 40i is formed of a cylindrical sleeve 21, 41 which extends in the direction of the axis of rotation AX, extended by a lateral annular flange 22, 42 perpendicular to the axis of rotation AX and inwards in the direction of this axis of rotation.

[0088] The cylindrical sleeve 21 of the first frame 20 is then adapted to be mounted by fitting into a hollow cylindrical housing 13 of the fixed element 11.

[0089] The annular strips 30 have an external diameter adapted to be housed in the cylindrical sleeve 21 of the first frame 20, a first face 35 of the first end 31 of the strips 30 being positioned against the lateral annular flange 22 of the first frame 20.

[0090] The cylindrical sleeve 41 of the second armature 40i is then adapted to be mounted by fitting into the internal surface of the cylindrical sleeve 21 of the first armature 20, until it presses the lateral annular flange 42 of the second armature 40i against a second face 36 of the strips 30 (at its first end 31), and therefore until it clamps by pinching the first end 31 of the strips 30 between the first armature 20 and the second armature 40i.

[0091] According to a variant, the lateral annular flange 22 of the first frame 20 and / or the lateral annular flange 42 of the second frame 40i may have surfaces adapted for holding, fixing the strips 30. For example, at least one of the surfaces has a surface condition, a roughness or a graining adapted to this fixing. In particular, the roughness of at least one of these surfaces may be increased compared to an average roughness of the corresponding frame. For example, at least one of these surfaces is worked to produce studs or projections, or grooves or furrows forming attachment shapes adapted to the fixing of the strips 30.

[0092] According to a variant, the second armature 40i has a radial height of the lateral flange less than a radial height of the lateral flange 22 of the first armature 20, so that the blades 30 are free to extend in the direction of the axis of rotation AX in a curved manner up to their second end 32, in the mounting position on the rotating element 12 of FIG. 1.

[0093] According to a variant, the second armature 40i is also capable of conducting an electric current. In this case, the path of the electric current can pass between the strips 30 and the first armature 20 as previously, but also between the strips 30 and the second armature 40i. The second armature 40i being mounted integral with the first armature 20, another branch of the path of the electric current can pass through the second armature 40i and then join the first armature 20. This arrangement makes it possible to increase the electrically conductive area of ​​the strips 30 towards the first armature 20, this electrically conductive area being substantially the sum of a first direct contact area between the strips 30 and the first armature 20 (or area of ​​a portion of the flange 22 of the first armature 20) and a second contact area between the strips 30 and the second armature 40i (or area of ​​a portion of the flange 42 of the second armature 40i).

[0094] Since the contact between the second armature 40i and the first armature 20 is a metal-metal contact, it has only a very low resistance to electrical conduction. Thus, thanks to the electrical conduction of the second armature 40i, the electrical conductivity of the ring 10 can be increased.

[0095] According to a second embodiment of the ring 10, as shown in FIG. 3 and FIG. 4, the fixing member 40 of the strips 30 comprises an overmolding 402 of the strips 30 on the first frame 20.

[0096] This overmolding 4Û2 has the effect of fixing the slats 30 on the first frame 20.

[0097] The overmolding 402 of the fixing member 40 is for example made of a material suitable for overmolding, such as an elastomer, a rubber, a nitrile rubber (NBR), a hydrogenated nitrile rubber (HNBR), a silicone, a thermoplastic, a polymer or a resin.

[0098] This overmolding 402 is possibly made of a material containing at least one electrically conductive filler, such as carbon or graphite. Thus, the electrical conductivity between the strips 30 and the first frame 20 is increased.

[0099] According to variants, the first frame 20 of this second embodiment may have arrangements similar or identical to the first frame 20 of the first embodiment; in particular, for example, with regard to the shape of this frame for mounting the ring, and / or for example with regard to the surface of the lateral annular flange 22 of the first frame (surface condition, roughness, attachment shapes).

[0100] According to a variant, the first frame 20 comprises recesses 24 (directly visible in FIG. 8A), and the overmolding material of the fixing member 40 passes through said recesses 24. Thanks to this arrangement, the fixing of the strips 30 to the first frame 20 is improved.

[0101] In particular, as can be seen in FIG. 4, the recesses 24 can be located in the intermediate spaces 37 between the slats 30. The overmolding 402 then advantageously extends in the circumferential direction on the first face 35 of the slats 30 and on the second face 36 of the slats 30.

[0102] This overmolding 402 can extend over one face of the slats 30 either discontinuously or continuously.

[0103] In the example shown in Figure 4, the overmolding 402 extends discontinuously on the first face 35 (on the first frame 20) and continuously on the second face 36 (on the slats 30). The slats 30 are thus effectively fixed to the first frame 20 by the overmolding 402 which passes through the first frame 20 and which extends in the circumferential direction of the ring 10. The slats 30 are held between an extension of the overmolding 402 in the circumferential direction and the first frame 20. The discontinuous overmolding 402 on the first face 35 forms a plurality of fixing studs 45. Figure 4 shows three fixing pads 45i, 452, 45s, each pad extending through a recess 24 and in a circumferential direction on one side on a first lamella 30 and on the other side on another adjacent lamella 30.

[0104] Figure 5 shows a particular example of application of the electrical balancing ring 10 according to any one of the embodiments previously described.

[0105] This figure shows a rolling bearing 1 comprising on at least one side an electrical balancing ring 10 as described above in order to ensure the transfer of electrical charges. The rolling bearing is for example a rolling bearing of a motor vehicle, and more particularly for example a rolling bearing of a motor vehicle wheel, as shown in Figure 5.

[0106] This rolling bearing 1 includes in particular:

[0107] - a fixed organ 2,

[0108] - a rotating member 3 driven in rotation by a shaft 5 and on which is fixed, for example, a vehicle wheel, and

[0109] - rolling bodies 4 arranged in the rolling space 4e formed between the fixed member 2 and the rotating member 3 to allow the relative rotation of the rotating member 3 with respect to the fixed member 2 around the axis of rotation X, while absorbing significant forces between the fixed member and the rotating member.

[0110] The fixed element 11 of the ring 10 is either directly the fixed member 2, or fixed to said fixed member 2 of the rolling bearing 1. The rotating element 12 of the ring 10 is either directly the rotating member 3, or fixed to said rotating member 3 of the rolling bearing 1.

[0111] The rolling bodies 4 may be balls or rollers or any other known type.

[0112] Thanks to the electrical balancing ring 10 according to the present disclosure, the rolling bearing 1 is able to transfer electrical charges to the fixed member and the rotating member, without passing through the rolling bodies, which can damage them. A vehicle equipped with such devices will thus be more reliable.

[0113] We will now explain a method of manufacturing an electrical balancing ring 10 according to the characteristics described previously, said manufacturing method being particularly advantageous. The electrical balancing ring 10 is intended to be mounted between a fixed element 11 and a rotating element 12 movable in rotation relative to the fixed element around an axis of rotation AX.

[0114] As shown in Figure 6A and Figure 6B, the method can begin by producing an annular type membrane 39. This membrane is for example produced from an annular disc of Figure 6A, substantially flat and which extends between an external diameter 39a and an internal diameter 39b.

[0115] The annular disc of Figure 6A is then cut by any method to form radial slots 39c distributed along the direction of the circumference of the membrane 39. These radial slots 39c extend from the outer diameter 39a to the inner diameter 39b of the membrane 39, without opening onto the inner diameter to maintain a continuous annular portion at the inner diameter 39b. The radial slots 39c thus form spaces in the membrane between tabs 39d. These radial slots 39c and spaces may be of the same shape or of different shapes or widths. The method for forming the radial slots 39c is for example a die-casting, punching, stamping, cutting, laser cutting, or water jet cutting method.

[0116] The membrane 39 then has the general shape of an annular disc with tabs 39d which extend radially outwards, said tabs 39d being separated from each other by slots 39c. The internal diameter 39b of this membrane 39 is kept annular and continuous in material. This internal diameter 39b can be used for positioning, which facilitates for example the assembly and / or cutting of this membrane, and reduces the cost thereof, as we will see below.

[0117] The method of manufacturing the electrical balancing ring 10 then generally comprises the following steps:

[0118] - a first annular, rigid armature 20 is provided, intended to be mounted securely on one of the fixed element and the rotating element, the first armature being capable of conducting an electric current,

[0119] - an annular membrane 39 is provided in the form of an annular disc with tabs which extend radially, as shown in FIG. 6B, the membrane 39 being made of an elastic material, and capable of conducting an electric current,

[0120] - the membrane 39 is fixed to the first frame 20 by a fixing member 40, and

[0121] - an annular portion of the membrane 39 is cut out to separate the tabs and form strips 30 separated from each other by intermediate spaces 37.

[0122] This produces one of the independent slats fixed to the first frame 20 by the fixing member 40.

[0123] According to a variant, the membrane 39 is positioned relative to the first frame 20 before its attachment. For example, the membrane 39 is positioned coaxially with the first frame 20. In particular, the internal diameter 39b of the membrane 39 can be used to carry out this positioning of the membrane 39. A centering tool is for example used to center the internal diameter 39b relative to the first frame 20 (for example, relative to the cylindrical sleeve 21 or relative to the lateral annular flange 22). This tool then comprises complementary surfaces to ensure coaxial centering.

[0124] Thanks to this positioning before fixing the membrane 39, it is possible to have a membrane with an external diameter 39a smaller than the diameter of the cylindrical sleeve 21, which makes it possible to save material on this external diameter. Thus, an inexpensive membrane is produced while ensuring precise positioning.

[0125] Furthermore, the cutting of the annular portion of the membrane 39 is a cutting around the internal diameter 39b of the membrane. Thus, the independent tabs 39d are formed.

[0126] This cutting of the annular portion of the membrane 39 is advantageously carried out coaxially with the first frame 20. This cutting is thus, for example, a circular cutting coaxial with the first frame 20, for example by reusing the previous centering tool.

[0127] This cutting can be carried out by any method, such as previously mentioned for the production of the radial slots 39c in the membrane 39. For example, this cutting is carried out by a die-cutting, punching, stamping, laser cutting, or water cutting process.

[0128] Figure 7 represents an example of a manufacturing method corresponding to the first embodiment of the electrical balancing ring 10 of Figure 1 and Figure 2.

[0129] In this first variant of the process:

[0130] - a first frame 20, of figure 7A, is provided,

[0131] - a membrane 39 is provided, from figure 6B,

[0132] - the membrane 39 is placed in the first frame 20,

[0133] - a fixing member 40 is provided in the form of a second frame 40i, of FIG. 7B,

[0134] - the membrane 39 is fixed to the first frame 20 by a fixing member 40, by fitting the second frame 40i into the first frame 20 until the membrane 39 is pinched between the first frame 20 and the second frame 40i, as shown in figure 7C,

[0135] - an annular portion of the membrane 39 is cut along the circumference Cl, separating the tabs and forming strips 30 separated from each other by intermediate spaces 37, as shown in figure 7D (the material of the membrane 39 between the circumference Cl and the internal diameter 39b of the membrane 39 is removed).

[0136] Optionally, an additional step of forming the first armature 20 can be carried out to bend an annular inner end 23 of the first armature 20, as shown in FIG. 7E. The independent strips 30 then bend in the direction given by the inner end 23, that is to say in the direction of the axis AX of the mounting of the electrical balancing ring 10 on the rotating element 12.

[0137] Figure 8 represents an example of a manufacturing method corresponding to the first embodiment of the electrical balancing ring 10 of Figure 3 and Figure 4.

[0138] In this second variant of the process:

[0139] - a first frame 20 is provided, of figure 8A, this first frame 20 possibly comprising recesses 24,

[0140] - a membrane 39 is provided, from figure 6B,

[0141] - the membrane 39 is placed in the first frame 20,

[0142] - a fixing member 40 is provided in the form of an overmolding 402, of figure 8B, this overmolding 402 fixes the tabs 39d of the membrane 39 to the first frame 20, as shown in figure 8B,

[0143] - an annular portion of the membrane 39 is cut along the circumference Cl, separating the tabs and forming strips 30 separated from each other by intermediate spaces 37, as shown in figure 8C (the material of the membrane 39 between the circumference Cl and the internal diameter 39b of the membrane 39 is removed).

[0144] Optionally, an additional step of forming the first armature 20 can be carried out to bend an annular inner end 23 of the first armature 20, as shown in FIG. 8D. The independent strips 30 then bend in the direction given by the inner end 23, that is to say in the direction of the axis AX of the mounting of the electrical balancing ring 10 on the rotating element 12.

[0145] At the stage of producing the overmolding 402, of FIG. 8B, this overmolding 402 forms the fixing member 40.

[0146] The overmolding 402 can pass through recesses 24 of the first frame 20 to form pads 45 (45i, 452, 45s), as shown in the figures.

[0147] Thus, the material of the overmolding 402 extends on a first side over the tabs 30, passes through the recesses 24 of the first frame 20 to then extend on a second side over the first frame 20. The tabs 30 are thus firmly fixed between the overmolding 402 of the first side and the first frame 20.

[0148] The overmolding 402 extends continuously around the entire circumference or discontinuously in patches as shown in the figures. Partial nomenclature of the elements of the figures

Claims

CLAIMS 1. Electrical balancing ring (10) intended to be mounted between a fixed element (11) and a rotating element (12) movable in rotation relative to the fixed element around an axis of rotation (AX), the ring comprising: a first, annular, rigid armature (20), mounted integrally on one of the fixed element and the rotating element, a plurality of lamellae (30) positioned on the first armature around the axis of rotation, made of an elastic material, each lamella extending between a first end (31) in contact with the first armature, and a second end (32) in contact with the other of the fixed element and the rotating element, a fixing member (40) adapted to fix the lamellae to the first armature, in which the first armature (20) and the lamellae (30) are capable of conducting an electric current between the fixed element and the rotating element, and the lamellae (30) are separated from each other by intermediate spaces (37).

2. Ring according to claim 1, in which the slats (30) have a rectangular, trapezoidal or angular sector shape.

3. A ring according to claim 1 or claim 2, wherein the plurality of lamellae (30) have shapes or lengths in a radial direction which are different.

4. Ring according to one of claims 1 to 3, in which the lamellae (30) are formed from a PTFE material containing at least one electrically conductive filler, such as carbon and / or graphite.

5. Ring according to one of claims 1 to 4, in which the lamellae (30) have at least one contact surface (34) covered with a coating capable of conducting an electric current, and made of a material containing silver, copper, aluminum, carbon, graphene or graphite.

6. Ring according to one of claims 1 to 5, in which the slats (30) have a wear reserve or embossing.

7. Ring according to one of claims 1 to 6, in which the fixing member (40) comprises at least one second, annular, rigid frame (40i), mounted integrally with the first frame (20) so as to fix by pinching the strips (30) between the first frame and the second frame.

8. Ring according to claim 7, in which the second armature (40i) is capable of conducting an electric current.

9. Ring according to one of claims 1 to 6, in which the fixing member (40) comprises at least one overmolding (402) of the strips (30) on the first frame (20).

10. Ring according to claim 9, in which the fixing member (40) is made of a material suitable for overmolding, such as an elastomer, an NBR elastomer, an HNBR elastomer, a silicone, a thermoplastic, a polymer or a resin.

11. Ring according to one of claims 9 to 10, in which the fixing member (40) is made of a material containing at least one electrically conductive charge, such as carbon and / or graphite.

12. Ring according to one of claims 9 to 11, in which the first frame (20) comprises recesses (24), and the overmolding material of the fixing member (40) passes through said recesses (24) to fix the strips (30) to the first frame (20).

13. Ring according to one of the preceding claims, in which the first armature (20) is curved in a direction of the axis of rotation to tilt the lamellae by contact in said direction.

14. Ring according to one of the preceding claims, in which the lamellae (30) are formed from an annular membrane (39) in the form of an annular disc with tabs (39d) which extend radially, and the membrane (39) being fixed to the first frame (20) by the fixing member (40), and the membrane (39) is cut over an annular portion of its internal diameter to separate tabs from the membrane and form the lamellae (30) separated from each other by intermediate spaces (37).

15. Rolling bearing (1) comprising an electrical balancing ring (10) according to one of claims 1 to 14, and rolling bodies (4) arranged in a rolling space to allow relative rotation of the rotating element with respect to the fixed element around the axis of rotation.

16. Method for manufacturing an electrical balancing ring (10), said ring being intended to be mounted between a fixed element (11) and a rotating element (12) movable in rotation relative to the fixed element around an axis of rotation (AX), said method comprising the steps of: - a first annular, rigid armature (20) is provided, intended to be mounted securely on one of the fixed element and the rotating element, the first armature being capable of conducting an electric current, - an annular membrane (39) is provided in the form of an annular disc with tabs (39d) which extend radially, the membrane being made of an elastic material, and capable of conducting an electric current, - the membrane (39) is fixed to the first frame (20) by a fixing member (40), and - an annular portion of the internal diameter of the membrane (39) is cut out to separate the tabs and form strips (30) separated from each other by intermediate spaces (37).

17. Method according to claim 16, in which the membrane (39) is formed from an annular disc in which radial slots (39c) are cut extending from an external diameter (39a) towards an internal diameter (39b), without opening onto the internal diameter in order to maintain a continuous annular portion at the level of the internal diameter (39b), said slots forming the tabs (39d).

18. Method according to claim 16 or claim 17, in which the membrane (39) is positioned relative to the first frame (20) before fixing this membrane, by an internal diameter (39b) of said membrane.

19. Method according to one of claims 16 to 18, in which the cutting of the annular portion of the internal diameter of the membrane is a cutting coaxial with the first reinforcement (20).

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