Device for coupling two shaft, assembly comprising such a device and method for manufacturing such a device

Abstract

The invention relates to a device (10) for coupling two shafts, comprising a first coupling half (12) connectable to one shaft, a second coupling half (13) connectable to the other shaft, the first coupling half (12) and the second coupling half (13) being rotatable together, the device (10) further comprises, in at least one of the coupling halves, a hub (18) rotatable about an axis of rotation (16) and a single ring (20) for coupling the hub to the shaft, the ring being electrically insulated. The invention also relates to an assembly comprising such a device and to a method for producing such a device.

Description

Technical Field

[0001] The invention relates to a device for coupling two shafts, an assembly comprising the device and a method for producing the device. Background Art

[0002] Document EP3655674 describes a coupler comprising at least one coupling half located on the input side and one coupling half located on the output side. The document aims to electrically isolate the axes of these couplers from each other. The coupler comprises at least two stacked hollow cylinders, which are fixed to each other and arranged in the holes of the coupling half. The first cylinder is made of a conductive material and the second cylinder is made of an electrically insulating material. Knurling is provided on the outer surface and inner surface of the first cylinder and on the inner surface of the hole facing the first cylinder. Because knurling allows a form-fitting connection between contact surfaces, knurling of the surface is provided in this document to ensure material blocking between the elements of the coupler.

[0003] In order to manufacture the second barrel, epoxy resin is injected between the first barrel and the inner surface of the hole facing the first barrel. This causes the concentricity problem between the first barrel and the hole. If the epoxy resin is not perfectly distributed around the first barrel (possibly due to the concentricity problem), the injection has the risk of producing imbalance, thereby causing imbalance when the coupler rotates. In addition, the injection molding of the second barrel requires the presence of the first barrel to form an annular space with the hole. In addition, since the second barrel of epoxy resin is fragile, this coupler requires the presence of the first steel ring to ensure coupling with the shaft, and does not allow the second barrel to be easily replaced. Therefore, this coupler is complicated, difficult to achieve, and expensive.

[0004] What is needed is a coupling device and simpler method of manufacture that allows the coupling halves to be electrically isolated from each other. Summary of the invention

[0005] To this end, the present invention proposes a device for coupling two shafts, the device comprising a first coupling half suitable for connection to one shaft, a second coupling half suitable for connection to the other shaft, the first coupling half and the second coupling half suitable for being driven to rotate together, the device also comprises a hub movable in a rotational manner around a rotation axis and a ring for coupling the hub to the shaft in at least one of the coupling halves, the ring being electrically insulating. In particular, the device comprises a single ring for coupling the hub to the shaft, the ring being electrically insulating.

[0006] In a variant, the ring is a torque limiter.

[0007] In one variation, the roughness of the inner surface of the hub is less than 0.8.

[0008] In a variant, the roughness of the inner and outer surfaces of the ring is less than or equal to 3.2.

[0009] In a variant, the ring has an outer surface of cylindrical or conical shape in contact with the hub.

[0010] In one embodiment, the conical shape of the outer surface of the ring flares in either direction along the axis of rotation.

[0011] In a variant, the ring has an outer surface in contact with the hub and of regular cross-section transverse to the axis of rotation.

[0012] In a variant, the ring has an outer surface in contact with the hub having an irregular cross section transverse to the axis of rotation.

[0013] In a variant, the ring has an outer surface in contact with the hub and having an elliptical or polygonal section transverse to the axis of rotation.

[0014] In a variant, the ring has a regular or stepped outer surface along the axis of rotation.

[0015] In one embodiment, the ring has an inner surface that is parallel to the surface of the shaft.

[0016] According to one variant, the ring and / or the hub have a configuration that limits the relative displacement of the other of the ring or the hub along the axis of rotation.

[0017] In a variant, the configuration of the ring and / or the hub comprises a shoulder transverse to the axis of rotation.

[0018] According to a variant, the formation of the ring and / or the hub comprises a groove cooperating with the shoulder.

[0019] In one embodiment, the device further comprises an electrically insulating plate transverse to the axis of rotation, the plate and the ring defining an insulating housing for receiving the shaft.

[0020] In one embodiment, the device further comprises a protection piece made of a material more rigid than the electrically insulating plate, the protection piece being located on the face of the plate facing the outside of the housing.

[0021] In one embodiment, the device is a tooth coupling, a disc coupling, a diaphragm coupling, a universal joint, a rigid coupling or a hollow torque shaft coupling.

[0022] In a variant, the coupling between the ring and the hub is frictional.

[0023] In a variant, the ring is obtained by machining a solid bar or by machining a tube or by moulding.

[0024] In a variant, the ring is located in the coupling half that drives the other coupling half in rotation.

[0025] In a variant, the ring is made of a polymer such as polyamide or polyetheretherketone.

[0026] In a variant, the hub comprises a hole into which the ring is shrunk.

[0027] The invention also relates to an assembly comprising a device as described above, a first shaft coupled to one hub via the ring, a second shaft coupled to the other hub.

[0028] In a variant, the ring is a torque limiter.

[0029] In a variant, the ring is pressed against the hub by the shaft.

[0030] According to a variant, the assembly also comprises an electrically insulating plate transverse to the axis of rotation and attached to the end of the shaft coupled to the hub by the ring.

[0031] In one embodiment, the assembly further comprises a protection member made of a material more rigid than the electrically insulating plate.

[0032] In a variant, a screw attaches the electrically insulating plate and the protector to the end of the shaft coupled to the hub by the ring, the screw comprising a head that abuts against the protector.

[0033] In a variant, the shafts are coupled in the ring and in the hub, respectively, by shrink fitting.

[0034] The invention also relates to a method for manufacturing a coupling device as described above, the method comprising: providing a first coupling half adapted to be connected to one shaft, a second coupling half adapted to be connected to another shaft, the first coupling half and the second coupling half adapted to be driven to rotate together; providing an electrically insulating ring; assembling the ring in a hub of one of the two coupling halves. In particular, the method comprises providing a single ring for coupling the hub to the shaft, the ring being electrically insulating.

[0035] In a variant, the ring is assembled to the hub by a shrink-fitting step.

[0036] Alternatively, the ring is obtained by machining a solid bar or a tube or by moulding.

[0037] In a variant, the inner surface of the hub in contact with the ring is obtained by machining, preferably by turning and / or grinding.

[0038] In a variant, the device is assembled to a shaft and the ring is pressed against the hub by the shaft.

[0039] In this document, the use of the verb "comprise" and its conjugations and variations does not in any way exclude the presence of elements other than those mentioned. The use of "a", "an" or "the" to introduce an element in this document does not exclude the presence of a plurality of such elements.

[0040] The terms “first”, “second”, etc. in the context of this document are only used to distinguish different elements but do not imply any order between these elements.

[0041] All preferred embodiments and all advantages of the coupling device according to the invention apply mutatis mutandis to the assembly and the method of production according to the invention and vice versa.The various embodiments can be considered individually or in combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Other features and advantages of the present invention will become apparent from the following detailed description, which can be understood by referring to the accompanying drawings, in which:

[0043] - Figure 1 A schematic diagram showing an example of an embodiment of a coupling device;

[0044] - Figure 2 Shows Figure 1 A schematic diagram of an example of an embodiment of a detail of a coupling device is shown;

[0045] - Figure 3 Shows Figure 1 A schematic diagram of another example of an embodiment of a detail of a coupling device is shown.

[0046] The drawings in the accompanying drawings are not drawn to scale. In the accompanying drawings, similar elements are generally represented by similar reference numerals. Within the scope of this document, the same or similar elements may have the same reference numerals. In addition, the presence of reference numbers or letters in the accompanying drawings should not be considered as limiting, even if these numbers or letters are pointed out in the claims. DETAILED DESCRIPTION

[0047] The invention relates to a device for coupling two shafts, the device comprising a first coupling half adapted to be connected to one shaft and a second coupling half adapted to be connected to the other shaft. The first coupling half and the second coupling half can be driven to rotate together. The device also comprises, in at least one of the coupling halves, a hub movable in a manner rotating around an axis of rotation and a ring for connecting the hub to the shaft, the ring being electrically insulating. The advantage of the device is that the coupling halves are electrically insulated from each other by a ring of insulating material. In addition, since the ring ensures that the hub is coupled to the shaft, the device is simple and easy to manufacture.

[0048] Figure 1 A schematic diagram of an example of an embodiment of a coupling device 10 is shown. The device 10 can be installed in a drive kinematic chain, such as in a vehicle (such as a car, bus or train) or a rolling mill. The device 10 is a toothed coupling, a disc coupling, a diaphragm coupling, a universal joint, a rigid coupling or a hollow torsion shaft coupling. In this way, the present invention is applicable to a wide variety of coupling devices.

[0049] The device 10 allows two shafts 8 and 9 to be coupled. The device allows rotational movement around an axis of rotation 16 to be transmitted from one shaft (input shaft) to another shaft (output shaft); for example, shaft 8 can be a drive shaft or input shaft, and shaft 9 can be a driven shaft or output shaft. The shafts can move in a manner rotating around the axis of rotation 16, and the axis of rotation 16 can be roughly common to the two shafts. It is conceivable that there is an angle between the axes of rotation of the shafts. The drive shaft is rotated by a driven machine (motor, gearbox, reducer, etc.). The device 10 allows shafts 8 and 9 to be axially offset. The device also allows the shafts to be displaced radially and angularly, or allows the shafts to be displaced angularly. In this way, the device 10 can be applicable to a variety of couplings.

[0050] The device 10 comprises a first coupling half 12 adapted to be connected to one shaft, such as the shaft 8, and a second coupling half 13 adapted to be connected to another shaft, such as the shaft 9. Figure 1 The shafts are connected and coupled to each half 12, 13 along their respective axes of rotation 16, 17. The axes of rotation 16, 17 are Figure 110 is shown as being coaxial, but may not be coaxial (and may be radially or angularly offset as described above). More specifically, the end of a shaft is connected, coupled to each half 12, 13. The first coupling half 12 and the second coupling half 13 can be driven to rotate together. This allows speed and torque to be transmitted from the shaft of one coupling half toward the shaft of the other coupling half. For example, the (first) coupling half 12 is the driving part (or input part) of the device 10, which is connected to the input shaft 8, and the (second) coupling half 13 is the driven part (or output part) of the device 10, which is connected to the output shaft 9. In other words, the driving movement of the shaft coupled to the coupling half 12 is transmitted to the shaft coupled to the coupling half 13. Conversely, the (second) half 13 may be the driving part and the (first) half 12 may be the driven part, so that one coupling half or the other is the driving part and the other coupling half is the driven part.

[0051] In each of the coupling halves 12, 13, the device 10 may also include a hub 18, 19 that can move in rotation about its own axis of rotation 16 and 17, respectively (these axes may or may not be coaxial). Depending on the coupling half in which the hub 18, 19 is located, the hub allows the transmission of rotational movement from the driving shaft to the other coupling half, or from the other coupling half to the driven shaft. Figure 1 , either of the coupling halves 12, 13 can be a driving part (corresponding to the input part of the coupling device) or a driven part (corresponding to the output part of the driving device). Hereinafter, in order to simplify the present description, as an example, the coupling half 12 is the driving part, and the coupling half 13 is the driven part.

[0052] The device 10 may also include one or more sleeves 24, 25 located in the coupling halves 12, 13, respectively. The sleeves 24, 25 for each half 12, 13 are shown in the drawings by way of example, and an example of a toothed coupling is given in the drawings by way of example. The sleeves 24, 25 are attached to each other, or may be made into a single-piece component, and are driven to rotate around a common axis of rotation or around their own axis of rotation, respectively. The sleeve 24 is driven to rotate by the hub 18 via teeth 26. The sleeve 24 driven to rotate by the hub 18 then drives the sleeve 25 of the coupling half 13. Then, the sleeve 25 drives the hub 19 via teeth 27. In the case of a disc coupling, the sleeves 24 and 25 are driven via a disc group. The sleeve 24 can be driven to rotate by a flexible connection (teeth, grouped discs, diaphragms, etc.) or a rigid connection (hollow torsion shaft or rigid coupler) with the hub 18. The sleeve 25 then drives the hub 19 either by a flexible connection (teeth, grouped discs, diaphragms) or a rigid connection.

[0053] The device 10 may also comprise covers 28, 29 respectively located in the coupling halves 12, 13. The covers 28 and 29 are respectively attached to the sleeves 24 and 25. The sleeves 24, 25 and the covers 28, 29 allow the teeth 26, 27 to be isolated from the environment, in particular from dust.

[0054] The device 10 also includes a ring 20 for coupling the hub to the shaft. The ring 20 couples the shaft to the hub in either of the coupling halves 12, 13. The ring 20 couples the shaft directly to the hub in either of the coupling halves 12, 13. As an example, in Figure 1 In the embodiment, the ring 20 couples the hub 18 to the shaft 8 in the coupling half 12, which drives the other coupling half 13 in rotation. Thus, the ring 20 can be located in the driving part of the device 10, but can also be located in the driven part to couple the hub 19 to the shaft 9.

[0055] The ring 20 allows the hub 18 to be connected to the shaft 8. The ring 20 allows the hub 18 to be directly connected to the shaft 8. The ring 20 is in contact with the hub 18 and the shaft 8. The ring 20 is in direct contact with the hub 18 and in direct contact with the shaft 8. The outer surface and the inner surface of the ring 20 are in contact with the hub 18 and the shaft 8, respectively. The outer surface and the inner surface of the ring 20 are in direct contact with the hub 18 and the shaft 8, respectively. The ring 20 allows torque to be transmitted between the shaft 8 and the hub 18 (in either direction, depending on the relevant coupling half). The ring 20 allows torque to be transmitted directly between the shaft 8 and the hub 18 (in either direction, depending on the relevant coupling half). The ring 20 transmits power between the shaft 8 and the hub 18. The ring 20 transmits power directly between the shaft 8 and the hub 18. Therefore, there is no power loss. The device 10 includes only one coupling portion between the hub 18 and the shaft 8, namely the ring 20. The ring 20 is a single coupling ring between the hub and the shaft, which is made of an insulating material. The ring 20 is a single ring between the hub 18 and the shaft 8. The ring 20 is a single intermediate ring between the hub 18 and the shaft 8. In other words, the ring 20 couples the hub 18 directly to the shaft 8. There are no other parts between the hub 18 and the shaft 8 except the ring 20 that allow torque transmission. When assembling the device 10, the ring 20 allows concentricity, which facilitates the assembly of the device 10. This allows to simplify the assembly of the device 10 and makes the device simpler and cheaper. The position of a single part is installed and adjusted between the shaft 8 and the hub 18. The ring 20 can also be easily replaced if it becomes worn.

[0056] The ring 20 is electrically insulating. This allows the two shafts to be electrically isolated by the two coupling halves 12, 13. This allows the electrical contact to be interrupted along the kinematic chain of the assembly device 10. The use of an electrically insulating ring 20 makes it easy to isolate the shafts 8 and 9 from each other by the device 10. The use of a single ring between the hub 18 and the shaft 8 allows the costs of making the coupling and ensuring the electrical insulation to be reduced compared to the solutions in the prior art (in particular the document EP3655674, which involves two additional cylinders).

[0057] The ring 20 is an annular component before manufacturing the device. The ring 20 is provided in the form of a ring. The ring 20 is a component that has an annular structure itself. Regardless of the position of the ring 20 in the device, the ring 20 has its own annular structure. The ring 20 is assembled in the form of a ring in the hub of one of the two coupling halves. The ring 20 exists in the form of a ring in the hub of one of the two coupling halves. The shape of the ring 20 is not obtained by pressing or injecting it into the device. In this way, for example, if the ring is worn, the ring 20 can be easily replaced. It is also possible to provide the device 10 with a ring 20 that is present in the hub independently of the installation on the shaft.

[0058] The material of the ring 20 is chosen to be electrically insulating. Furthermore, since the ring provides the coupling between the ring 20 and the shaft, the material of the ring is chosen to withstand high axial and radial loads and pressures (this is not the case in document EP3655674, where the second cylinder may be fragile). The material of the ring 20 also allows the ring to withstand harsh environments, in particular dust. The material of the ring 20 is also chosen to make the ring easier to manufacture. The material is a polymer, such as polyamide or polyetheretherketone.

[0059] The ring may be a torque limiter. This allows the absorption of torque differences between the drive part and the driven part. For example, in the event of a momentary blockage of an element of the kinematic chain (such as a blockage of the wheels of a train or a failure when introducing a sheet into a rolling mill), the driven coupling half of the device is slowed down by a braking torque rather than by the driving coupling half. The device 10 allows the absorption of excess torque from the drive part, which makes it possible to brake the driven part without damaging the drive part or the drive motor. This may not be possible in the devices of the prior art. In particular, this may not be possible when the contact parts are deeply textured (for example by knurling) in order to increase the clamping between the rotating parts. In particular, this may not be possible by the coupler of document EP3655674, in which there are knurlings on the inner surface of the hole of the second clutch half and on the outer surface of the first cylinder to ensure that the material of the second cylinder is anchored. This anchoring blocks the contact of the materials and therefore prevents torque limitation, in particular torque limitation by sliding. Specifically, the epoxy is injected to form the second cylinder so as to be in rigid contact with the knurling on the first cylinder and with the knurling on the inner surface of the bore of the second clutch half, thereby preventing torque limitation.

[0060] The coupling between the ring 20 and the hub (e.g., 18) is frictional. The ring 20 can rotate freely in the hub 18, and is braked only by the friction generated by the compressive stress between the hub 18 and the ring 20. Installing the shaft 8 allows the ring 20 to be pressed against the hub 18. Pressing the shaft 8 into the ring 20 presses the ring 20 against the hub 18. This allows the coupler to be frictionally locked while allowing sliding to limit torque. The pressure between the shaft 8, the hub 18, and the ring 20 is adjusted so that the friction torque (or force) is at a certain threshold. When the braking torque exceeds the threshold, the friction torque is less than the braking torque, and sliding occurs between the shaft 8 and the hub 18 through the ring 20. As the braking torque decreases and falls below the threshold, the friction torque becomes greater than the braking torque, and the sliding between the shaft 8 and the hub 18 stops through the ring 20; the driving half drives the driven half again. The material of the ring 20 is selected to transmit torque between the shaft and the hub by friction.

[0061] Torque is limited by the slip between the shaft 8 and the hub 18 by the ring 20. Preferably, the torque limiting slip occurs at the interface between the ring and the hub, rather than at the interface between the ring and the shaft, so as not to alter the surface condition of the shaft (a shaft is more complicated and expensive to replace than a hub).

[0062] The roughness of the inner and outer surfaces of the ring 20 may be less than or equal to 3.2 (corresponding to the arithmetic mean deviation along the profile Ra of the ring. The unit is μm). This roughness allows the hub 18 to be frictionally driven by the shaft 8 through the ring 20, while at the same time ensuring the sliding between the shaft 8 and the hub 18 through the ring 20 if an excessive braking torque occurs in the kinematic chain. This roughness ensures the sliding between the shaft 8 and the hub 18 through the ring 20 if an excessive braking torque occurs on the other coupling half 13 without damaging the surface of the ring 20. This roughness also allows preventing the ring 20 from being damaged by assembling the ring 20 during the manufacture (or assembly) of the device. An inner surface roughness of less than or equal to 3.2 corresponds to a smooth surface. Other higher roughness values ​​may also be suitable.

[0063] A hub (eg, Figure 1The hub 18 on the coupling half 12 (corresponding to the driving part) can have an inner surface with a roughness of less than 0.8 (corresponding to the arithmetic mean deviation of the profile Ra. The unit is μm.). The inner surface of the hub 18 corresponds to the surface of the hole 22. This roughness allows the hub 18 to be frictionally driven by the shaft through the ring 20, while at the same time ensuring the sliding between the shaft 8 and the hub 18 through the ring 20 if an excessive braking torque occurs on the other coupling half 13. This roughness ensures the sliding between the shaft 8 and the hub 18 through the ring 20 if an excessive braking torque occurs on the other coupling half 13 without damaging the surface of the ring 20. This roughness also allows preventing the ring 20 from being damaged due to assembling the ring 20 during manufacture (or assembly) of the device. A surface roughness of less than 0.8 corresponds to a smooth surface. Other higher roughness values ​​may also be suitable.

[0064] The ring 20 can be assembled and held in place in the coupling half by shrinking. The hub 18 includes a hole 22 into which the ring 20 shrinks. The ring 20 is held in place in the device 10 by an interference fit. The outer surface of the ring 20 rests against the inner surface of the hole 22.

[0065] The ring 20 may have a cylindrical outer surface that contacts the hub 18. Thus, along the axis of rotation 16, the outer surface is regular and has a constant diameter. This makes it easy to manufacture the ring and to assemble the ring to the device 10. Alternatively, the ring 20 may have a conical outer surface that contacts the hub 18. The conical shape of the outer surface of the ring 20 may expand in either direction along the axis of rotation 16. For example, the conical shape may expand in the direction in which the shaft 8 is inserted into the ring 20; Figure 1 In the embodiment, as an example, the outer surface of the ring can be expanded from left to right. This allows to prevent the hub 18 from moving towards the inside of the device 10. On the contrary, the conical shape can widen in the direction opposite to the direction in which the shaft 8 is inserted into the ring 20; Figure 1 In the embodiment of the invention, the outer surface of the ring can widen from right to left, as an example. This allows preventing the hub 18 from moving outwards from the device 10. In both cases where the outer surface of the ring 20 has a taper, the hole 22 of the hub 18 is also conical, its shape complementing that of the ring 20.

[0066] The outer surface of the ring may be regular or stepped along the axis of rotation 16. A flat surface makes it easier to manufacture the ring 20. A stepped surface makes it easier to insert the ring 20 into the hub. The stepped surface also allows the ring 20 to be more effectively retained in the hub 18 axially in one direction.

[0067] Alternatively or in combination, the outer surface of the ring can have various cross-sectional shapes transverse to the axis of rotation 16. The outer surface of the ring 20 in contact with the hub 18 can have a regular or irregular cross-section transverse to the axis 16. For example, the irregular cross-section is elliptical. This allows improved torque transmission from the ring 20 to the hub 18, and vice versa (for the driven half). For example, the irregular cross-section is polygonal. This allows torque to be transmitted by mechanical blocking. The advantage is that this allows good torque transmission between the shaft and the ring while limiting friction; this allows limiting the stress of the shaft on the ring, and therefore limiting the stress in the ring. For example, the regular cross-section is circular. Regular cross-sections allow easy manufacture of the ring 20, while irregular cross-sections allow torque to be transmitted without the need for friction.

[0068] The ring 20 may have an inner surface that is in contact with and parallel to the surface of the shaft. The ring 20 may also have a conical inner surface that expands outward from the inside, and the shape of the conical inner surface is complementary to the shape of the end of the shaft in the ring 20.

[0069] The ring 20 can be machined from solid bar stock. This provides more freedom in terms of the shape and size of the ring. Alternatively, the ring 20 can be machined from tubular stock. This means that the ring can be produced faster and with less material loss. Alternatively, the ring 20 can be obtained by molding, in particular by thermoforming or injection molding. This allows to ensure the consistency of the shape and size of the ring and also allows a great deal of freedom in terms of the shape of the ring. Furthermore, molding allows the fibers of the molding material to be oriented transversely to the axis of the ring 20 so that the ring has better resistance to expansion. Regardless of how the ring 20 is produced, the ring has its own ring structure. Independently of the presence of the ring in the device, the ring 20 has its own annular structure.

[0070] The inner surface of the hub 18 of the coupling half 12 can be obtained by machining (or mechanical processing), preferably by turning and / or grinding. This allows the hub to be manufactured to close machining tolerances. Machining is performed to obtain a surface finish of the hub 18 with a roughness as described above. The hub 19 can have a different Figure 1 The shape shown. Figure 1 In the embodiment of the present invention, the two halves are symmetrical. This symmetry makes it easier to manage the components, since one coupling half can be mounted on any type of shaft. However, there can be different shaft / hub interfaces between half 12 and half 13. The machining of the hub 19 of part 13 will then be adapted to obtain the desired interface.

[0071] The device 10 may include an electrically insulating plate 30 transverse to the axis of rotation 16. The plate 30 and the ring 20 define an insulating housing for receiving a shaft. The plate 30 is located at the end of the shaft coupled to the ring 20. The outer edge of the plate 30 can be in contact with the ring 20 and the hub 18. In this way, the ring 20 and the plate 30 provide electrical insulation for the drive shaft (or driven shaft, depending on the configuration of the device). The material of the plate 30 can be the same as the material of the ring 20 and have the same features and advantages. In particular, the plate 30 is used to prevent the hub 18 from translating toward the interior of the device 10, especially when the ring 18 has a conical shape that opens outward.

[0072] The device 10 may also include a protective member 32, which is made of a material that is more rigid than the electrically insulating plate 30. The protective member 32 allows the plate 30 to be protected. In particular, the protective member 32 is located on the face of the plate 30 opposite to the shaft. The protective member 32 is located outside the housing defined by the ring 20 and the plate 30. The plate 30 and the protective member 32 together form a safety plate. The plate 30 and the protective member 32 can be attached to the end of the shaft coupled to the hub 18 by the ring 20. In particular, an attachment member (such as a screw) 34 fixes the plate 30 and the protective member 32 to the shaft. If the attachment screw 34 is used, the head of the screw is placed against the protective member 32. Therefore, the protective member 32 prevents the electrically insulating plate 30 from being deformed due to the shaft attachment member. For example, the protective member 32 is made of steel.

[0073] Figure 2 and Figure 3 yes Figure 1 Schematic diagram of an example of an embodiment of a detail of the coupling device 10. In particular, in Figure 2 and Figure 3 In the device 10, the ring 20 and / or the hub 18 has a configuration that limits the relative displacement of the other of the ring 20 or the hub 18 along the rotation axis 16. The configuration hinders the relative movement of the two components. The configuration of the ring 20 and / or the hub 18 extends transversely to the axis 16. The configuration allows the two components to be anchored along the rotation axis 16. The ring 20 and the hub 18 have reduced, limited, or no relative movement.

[0074] The configuration of the ring 20 and / or the hub 18 may include shoulders 36, 38, 40 transverse to the axis of rotation 16. The shoulders form a ring that prevents the components from moving relative to each other. The configuration of the ring 20 and / or the hub 18 may also include grooves 42, 44, 46 that cooperate with the shoulders 36, 38, 40 to limit or even prevent relative movement of the ring 20 and the hub 18 along the axis 16.

[0075] according to Figure 2, the ring 20 includes a shoulder 36 at one end along the axis of rotation 16 and a groove 42 at the other end. The hub 18 includes a groove 44 that cooperates with the shoulder 36 of the ring 20 and a shoulder 38 that cooperates with the groove 42 of the ring. The shoulder 36 extending radially outward into the groove 44 limits the movement of the ring 20 toward the interior of the device 10; the shoulder 38 extending radially inward into the groove 42 limits the movement of the ring 20 toward the exterior of the device 10. In this way, the relative movement of the ring 20 and the hub 18 along the axis of rotation 16 is limited or even prevented.

[0076] according to Figure 3 , the ring 20 or the hub 18 includes a shoulder 40 located between the ends of the ring 20. The shoulder 40 cooperates with a groove 46 on the other component. For example, the ring 20 includes a shoulder 40 located between its ends, which cooperates with a groove 46 on the hub 18. The shoulder 40 can form a grip in the groove 46. The shoulder 40 extending radially outward into the groove 46 limits the movement of the ring 20 along the rotation axis 16 in both directions. In this way, the relative movement of the ring 20 and the hub 18 along the rotation axis 16 is limited or even prevented.

[0077] The invention also relates to an assembly comprising the device 10, a first shaft such as shaft 8 coupled to one hub such as hub 18 via a ring 20, and a second shaft coupled to another hub such as hub 19. All features and benefits described above apply to the assembly and vice versa.

[0078] The present invention also relates to a method for manufacturing (or assembling) a device 10 and an assembly comprising the device 10. The method comprises providing a first coupling half (such as half 12) adapted to be connected to a shaft (such as 8), a second coupling half (such as half 13) adapted to be connected to another shaft (such as 9). The first coupling half and the second coupling half can be driven to rotate together. The method also comprises providing an electrically insulating ring 20. The ring 20 is an annular component before manufacturing the device. The ring 20 is provided in the form of a ring. The ring 20 is provided with its own structure in the form of a ring. The shape of the ring 20 is not obtained by pressing or injecting it into the device. For example, in the event of wear, the ring 20 is easily replaced. The method then comprises assembling the ring in a hub (such as hub 18) of one of the two coupling halves (such as half 12). The ring 20 is assembled as a ring in the hub of one of the two coupling halves during the manufacture of the device 10. The ring 20 can be assembled to the hub independently of the connection of the device to the shaft. In this method, a single electrically insulated coupled ring 20 is provided and assembled between the hub and the shaft to form the device. In addition, the ring 20 will not be damaged during assembly to the hub. The ring 20 can be loosely assembled in the hub, or even without any physical contact between the ring and the hub. Before being assembled on the shaft 8, the ring can rotate and move axially completely freely. Only when it is installed or assembled on the shaft 8 (of the machine), the surfaces are in contact, and the friction connection between the ring and the hub is established. By inserting the shaft 8 into the ring 20, the ring 20 can be pressed against the hub 18. The shaft 8 is inserted into the ring 20 to (directly) contact with the inner surface of the ring 20. The ring 20 contacts the shaft 8 and the hub 18. The ring 20 is in direct contact with the shaft 8 and is in direct contact with the hub 18. The ring 20 can also be assembled to the hub 18 by a shrink fit step. The ring can be obtained by machining a solid bar or machining a tube or by molding (e.g., by thermoforming or injection). Regardless of how the ring 20 is produced, the ring has its own ring structure. Independent of the presence of the ring in the device, the ring 20 has its own annular structure. The inner surface of the hub 18 in contact with the ring 20 can be machined, preferably by turning and / or grinding. All the features and advantages described above apply to this method.

[0079] The invention has been described above in conjunction with specific embodiments, which are illustrative and should not be considered as limiting. In general, it will be apparent to a person skilled in the art that the invention is not limited to the examples shown and / or described above. For example, the ring 20 may perform an electrical insulation function within the device, or a torque limiter function between the shaft and the hub, or both electrical insulation and torque limiter functions between the shaft and the hub.

Claims

1. A device (10) for coupling two shafts, the device comprising: a first coupling half (12) adapted to be connected to a shaft, a second coupling half (13) adapted to be connected to another shaft, The first coupling half (12) and the second coupling half (13) are adapted to be driven to rotate together, The device (10) further comprises, in at least one of the coupling halves: a hub (18) which is movable in rotation about an axis of rotation (16), • A single ring (20) for coupling the hub to the shaft, the ring being electrically insulating.

2. The device according to claim 1, wherein: The ring is a torque limiter.

3. A device according to any one of the preceding claims, wherein: The roughness of the inner surface of the hub (18) is less than 0.

8.

4. A device according to any one of the preceding claims, wherein: The roughness of the inner surface and the outer surface of the ring (20) is less than or equal to 3.

2.

5. A device according to any one of the preceding claims, wherein: The ring (20) has an outer surface in a cylindrical or conical shape that contacts the hub (18).

6. Device according to the preceding claim, wherein The conical shape of the outer surface of the ring (20) flares in either direction along the axis of rotation (16).

7. A device according to any one of the preceding claims, wherein: The ring (20) has an outer surface in contact with the hub (18) and having a regular cross-section transverse to the axis of rotation (16).

8. The device according to any one of claims 1 to 6, wherein: The ring (20) has an outer surface in contact with the hub (18) having an irregular cross-section transverse to the axis of rotation (16).

9. The device according to any one of the preceding claims, wherein: The ring (20) has an outer surface in contact with the hub (18) and having an elliptical or polygonal cross-section transverse to the axis of rotation (16).

10. The device according to any one of the preceding claims, wherein: The ring (20) has a regular or stepped outer surface along the rotation axis (16).

11. The device according to any one of the preceding claims, wherein: The ring (20) has an inner surface parallel to the surface of the shaft (8).

12. The device according to any one of the preceding claims, wherein: The ring (20) and / or the hub (18) have a configuration that limits relative displacement of the other of the ring (20) or the hub (18) along the rotation axis (16).

13. Device according to the preceding claim, wherein The configuration of the ring (20) and / or the hub (18) includes shoulders (36, 38, 40) transverse to the axis of rotation (16).

14. Device according to the preceding claim, wherein The configuration of the ring (20) and / or the hub (18) includes grooves (42, 44, 46) that cooperate with the shoulders (36, 38, 40).

15. Device according to any of the preceding claims, further comprising an electrically insulating plate (30) transverse to the axis of rotation, said plate (30) and said ring (20) defining an insulating housing for receiving a shaft.

16. Device according to the preceding claim, further comprising a protection element (32) made of a more rigid material than the electrically insulating plate (30), the protection element (32) being situated on the face of the plate (30) facing the outside of the housing.

17. A device according to any of the preceding claims, of the type selected from the group consisting of a tooth coupling, a disc coupling, a diaphragm coupling, a universal joint, a rigid coupling, a hollow torsion shaft coupling.

18. A device according to any one of the preceding claims, wherein: The coupling between the ring (20) and the hub (18) is frictional.

19. The device according to any one of the preceding claims, wherein: The ring (20) is obtained by machining a solid bar or by machining a tube or by moulding.

20. The device according to any one of the preceding claims, wherein: The ring (20) is located in a coupling half (12) driving the other coupling half (13) in rotation.

21. The device according to any one of the preceding claims, wherein: The ring (20) is made of a polymer such as polyamide or polyetheretherketone.

22. A device according to any one of the preceding claims, wherein: The hub includes a bore (22) into which the ring (20) is shrunk.

23. A component, comprising: · a device (10) according to any one of the preceding claims, a first shaft (8) coupled to a hub (18) via the ring (20), A second shaft (9) coupled to a further hub (19).

24. Assembly according to the preceding claim, wherein The ring (20) is a torque limiter.

25. An assembly according to any one of claims 23 or 24, wherein The ring (20) is pressed against the hub (18) by the shaft (8).

26. An assembly according to any one of claims 23 to 25, further comprising an electrically insulating plate (30) transverse to the axis of rotation and attached to the end of the shaft coupled to the hub (18) through the ring (20).

27. An assembly according to claim 26, further comprising a protection member (32) made of a more rigid material than the electrically insulating plate.

28. The assembly of claim 27, wherein: A screw (34) attaches the electrically insulating plate (30) and the protector (32) to the end of the shaft coupled to the hub (18) via the ring (20), the screw (34) including a head that abuts against the protector (32).

29. An assembly according to any one of claims 23 to 28, wherein The shafts (8, 9) are coupled in the ring (20) and the hub (19), respectively, by shrink fitting.

30. A method for manufacturing a coupling device (10) according to any one of claims 1 to 22, the method comprising: providing a first coupling half (12) adapted to be connected to one shaft, a second coupling half (13) adapted to be connected to another shaft, the first coupling half and the second coupling half being adapted to be driven to rotate together, providing a single ring (20) for coupling the hub to the shaft, the ring being electrically insulating, Assembling the ring (20) in the hub (18) of one of the two coupling halves.

31. The method according to the preceding claim, wherein: The ring (20) is assembled to the hub by a shrink fitting step.

32. The method according to any one of claims 30 or 31, wherein: The ring (20) is obtained by machining a solid bar or a tube or by moulding.

33. The method according to any one of claims 30 to 32, wherein: The inner surface of the hub (18) in contact with the ring (20) is obtained by machining, preferably by turning and / or grinding.

34. The method according to any one of claims 30 to 33, wherein: The device (10) is assembled to a shaft (8), which presses the ring (20) against the hub (18).

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