Coupling for connecting the ends of two rotating shafts

Abstract

Coupling for connecting the ends (2A, 3A) of two rotating shafts (2, 3), comprising at least one surface which is at least partially covered with a friction coating (6) and is intended to come into contact at least partially with at least one of the ends (2A, 3A) of the two shafts (2, 3) to be connected, wherein the friction coating (6) comprises irregularities projecting from the at least one surface and pores. Furthermore, all or part of the friction coating (6) includes a sealant (7) that fills the pores formed between the irregularities of the friction coating (6).

Description

Technological field

[0001] The present invention relates generally to a shaft connection, in particular in drive systems and drive shafts, and more particularly to the sealing of the shaft connection.

[0002] In particular, the invention relates to a coupling for connecting the ends of two rotating shafts, a drive system comprising such a coupling, and a method for manufacturing such a coupling. background

[0003] Drive systems usually include multiple shafts, some of which need to be rotationally coupled.

[0004] Couplings are used to connect the ends of two adjacent shafts and transfer torque from one shaft to the other.

[0005] In particular, a certain group of couplings includes a friction coating that comes into contact with the ends of the two shafts to be connected. This friction coating significantly increases friction and provides greater torque capacity.

[0006] If the drive system includes a hollow shaft and a device containing oil or other fluid, a sealing function is required to prevent leakage between the shafts and the rest of the drive system.

[0007] A well-known solution is to attach sealing rings to the coupling ends.

[0008] However, this solution requires additional parts outside the clutch, which add additional complexity to the drive system.

[0009] The present invention therefore aims to overcome these disadvantages by providing a simple and lightweight sealing solution between the ends of the two shafts to be rotatably connected and a friction-coated coupling, which does not require the installation of additional components. Summary

[0010] The object of the invention is to provide a coupling for connecting the ends of two shafts, which coupling has at least one surface which is at least partially covered with a friction coating and is intended to come into contact at least partially with at least one of the ends of the two shafts to be connected, wherein the friction coating comprises asperities projecting from the at least one surface and pores.

[0011] In addition, all or part of the friction coating includes a sealant that fills the pores formed between the irregularities of the friction coating.

[0012] The sealant prevents oil or other fluids from leaking between the shafts and the coupling, and vice versa, and from escaping from the drive system. The coupling now incorporates a sealing function, eliminating the need for external or additional components such as sealing rings.

[0013] Preferably, the size of the pores is between 0 and 0.2 mm.

[0014] Preferably, the size of the unevenness is between 0 and 0.1 mm.

[0015] In this description, the limits of a range of values ​​are included in this range, in particular in the phrase “lies between ... and ...”.

[0016] Preferably, the sealant fills the pores of the friction coating at a height that extends from the lowest to the highest unevenness.

[0017] In a first embodiment, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the friction coating at least partially covering the inner surface of the inner sleeve.

[0018] According to a general feature, the sealant is located on two spaced regions, each located at one end of the inner sleeve, the sealant covering each region in the circumferential direction.

[0019] In a second embodiment, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with one of the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the inner sleeve comprising a flange having a radial surface intended to come into radial contact with a flange of the other of the ends of the two shafts to be connected, the friction coating at least partially covering the inner surface of the inner sleeve and the radial surface of the inner sleeve.

[0020] Alternatively, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with one of the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the inner sleeve comprising a flange having a radial surface intended to come into radial contact with a flange of the other of the ends of the two shafts to be connected, the friction coating at least partially covering the inner surface of the inner sleeve.

[0021] As a further alternative, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with one of the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the inner sleeve comprising a flange having a radial surface intended to come into radial contact with a flange of the other of the ends of the two shafts to be connected, the friction coating at least partially covering the radial surface of the inner sleeve.

[0022] Alternatively, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with one of the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the outer sleeve comprising a flange having a radial surface intended to come into radial contact with a flange of the other of the ends of the two shafts to be connected, the friction coating at least partially covering the inner surface of the inner sleeve and the radial surface of the outer sleeve.

[0023] As a further alternative, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with one of the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the outer sleeve comprising a flange having a radial surface intended to come into radial contact with a flange of the other of the ends of the two shafts to be connected, the friction coating at least partially covering the radial surface of the outer sleeve.

[0024] As a further alternative, the coupling may comprise an inner sleeve having an inner surface intended to come into axial contact with one of the ends of the two shafts to be connected, and an outer sleeve fixed around the inner sleeve, the outer sleeve comprising a flange having a radial surface intended to come into radial contact with a flange of the other of the ends of the two shafts to be connected, the friction coating at least partially covering the inner surface of the inner sleeve.

[0025] Preferably, the sealant comprises at least one polymer.

[0026] Advantageously, the sealant can be applied to the friction coating as a liquid polymer.

[0027] Another object of the invention is to provide a drive system comprising two rotating shafts and at least one clutch as described above, wherein the friction coating is frictionally connected to at least one of the ends of the two rotating shafts.

[0028] Another object of the invention is to provide a method for manufacturing a coupling as described above, which comprises applying a sealant to all or part of the friction coating on at least one surface of the coupling intended to come into contact with the ends of the two shafts.

[0029] Advantageously, the sealant can be applied by brushing, spraying or bathing.

[0030] Advantageously, the method for manufacturing a clutch may comprise a preparatory step of applying the friction coating to the at least one surface of the clutch by thermal spraying.

[0031] Advantageously, the method for manufacturing a coupling may comprise a step of smoothing at least one surface of the coupling intended to come into contact with the ends of the two shafts after the application of the sealing agent. Short description of the drawings

[0032] Further advantages and features of the invention will become apparent from the detailed description of embodiments of the invention, which are non-limiting examples, illustrated in the accompanying drawings, of which: Fig. Figure 1 is a sectional view through the longitudinal axis of a coupling connecting the ends of two shafts of a drive system according to a first embodiment of the invention; Fig. 2 a detailed view through a friction coating of the Fig. 1 shown coupling; and Fig. Figure 3 is a sectional view through the longitudinal axis of a coupling connecting the ends of two shafts of a drive system according to a second embodiment of the invention. Detailed description

[0033] Fig. 1 shows the ends 2A, 3A of a first and a second rotating shaft 2, 3 of a drive system and a coupling 1 attached to both shafts 2, 3 for connecting the two shafts to each other according to a first embodiment of the invention.

[0034] The two first and second shafts 2, 3 shown are hollow cylindrical shafts and extend along a common axis X.

[0035] The first and second shafts 2 and 3 comprise an outer surface 2a and 3a, respectively.

[0036] The coupling 1 comprises an inner sleeve 4 and an outer sleeve 5 which is fastened around the inner sleeve 4.

[0037] The inner sleeve 4 comprises an inner surface 4a which comes into axial contact with the outer surfaces 2a, 3a of the first and second shafts 2, 3.

[0038] In addition, the inner surface 4a of the inner sleeve 4 is covered with a friction coating 6, which is shown in a detailed view in Fig. 2, which comes into contact with the ends 2A, 3A of the first and second shafts 2, 3 to be connected. The entire inner surface 4a of the inner sleeve 4 can be covered with the friction coating 6. Alternatively, only a portion of the inner surface 4a of the inner sleeve 4 can be covered with the friction coating 6.

[0039] The friction coating 6 includes asperities projecting from the inner surface 4a of the inner sleeve 4, as well as pores. The pores extend inward from the inner surface 4a.

[0040] In addition, the friction coating 6 comprises a sealant 7.

[0041] The sealant 7 advantageously fills the pores formed between the irregularities of the friction coating 6. The sealant 7 is located on the inner surface 4a of the inner sleeve 4 and is thus positioned between the clutch 1 and the ends 2A, 3A of the first and second shafts 2, 3.

[0042] The sealant prevents oil or other fluids from leaking between shafts 2, 3 and coupling 1 and escaping from the drive system. Coupling 1 now also includes a sealing function.

[0043] The sealing function is contained in the coupling 1 and no external or additional components such as sealing rings are required.

[0044] Preferably, the sealant 7 fills the pores of the friction coating 6 at a height ranging from the lowest to the highest unevennesses, so that a sealing function is provided while the friction function is still fulfilled.

[0045] The sealant 7 may comprise at least one polymer.

[0046] In the example shown, the sealant 7 covers the entire inner surface 4a of the inner sleeve 4.

[0047] Alternatively, the sealant 7 may only partially cover the inner surface 4a of the inner sleeve 4.

[0048] For example, the sealant 7 may be located at two spaced regions, each located at one end of the inner sleeve 4, with the sealant 7 covering each region in the circumferential direction.

[0049] In the example shown, the coupling 1 comprises an inner and an outer sleeve 4, 5.

[0050] Alternatively, the clutch 1 may comprise a single sleeve mounted around at least one of the two shafts 2, 3 and comprising the friction coating 6 and the sealing means 7.

[0051] Fig. Figure 3 shows the ends 2A, 3A of the first and second rotating shafts 2, 3 connected by a coupling 8 according to a second embodiment of the invention.

[0052] The Fig. The embodiment shown in Figure 3, in which identical parts are provided with identical reference numerals, differs from the first embodiment of the Fig. 1 in that the ends 2A of the first shaft 2 comprise a flange 9 having a radial surface 2b.

[0053] The first shaft 2 can, for example, be part of a motor shaft or a gearbox.

[0054] The coupling 8 comprises an inner sleeve 10 and an outer sleeve 11 which is fastened around the inner sleeve 10.

[0055] The inner sleeve 10 includes an inner surface 10a which comes into axial contact with the end 3a of the second shaft 3.

[0056] At one of its ends, the inner sleeve 10 also comprises a flange 12 comprising a radial surface 10b which comes into contact with the radial surface 2b of the first shaft 2.

[0057] In addition, the inner surface 10a and the radial surface 10b of the inner sleeve 10 are covered with the friction coating 6, as previously described and shown in the detailed view of the Fig. 2. The friction coating 6 comes into contact with the radial surface 2b of the first shaft 2 and the outer surface 3a of the second shaft 3.

[0058] Furthermore, the friction coating 6 comprises the previously described sealant 7 filling its pores, the sealant 7 being arranged between the coupling 8 and the ends 2A, 3A of the first and second shafts 2, 3.

[0059] The sealing means 7 is located on the inner surface 10a and the radial surface 10b of the inner sleeve 10 and is thus positioned between the coupling 8 and the ends 2A, 3A of the first and second shafts 2, 3.

[0060] The sealant prevents oil or other fluids from leaking between the shafts 2, 3 and the coupling 8 and escaping from the drive system.

[0061] In the example shown, the coupling 8 comprises an inner and an outer sleeve 10, 11.

[0062] Alternatively, the clutch 8 may comprise a single sleeve secured around at least one of the first and second shafts 2, 3 and including the friction coating 6 and the sealant 7.

[0063] The invention also relates to a method for producing a clutch 1, 8 as described above, which comprises applying a sealing agent to the friction coating 6.

[0064] The sealant 7 can be applied by brushing, spraying or bathing.

[0065] Preferably, after applying the sealant 7 to the friction coating 6, the sealant 7 is smoothed so that the sealant 7 fills the pores of the friction coating 6 to a height that extends from the lowest to the highest unevennesses.

[0066] Advantageously, the method for manufacturing a clutch may comprise a preparatory step of applying the friction coating 6 by thermal spraying.

[0067] Preferably, the friction coating 6 is formed by plasma technology and may comprise carbide compounds.

Claims

[1] Coupling for connecting the ends (2A, 3A) of two shafts (2, 3), the coupling comprising at least one surface at least partially covered with a friction coating (6) and intended to come into contact at least partially with at least one of the ends (2A, 3A) of the two shafts (2, 3) to be connected, the friction coating (6) comprising asperities projecting from the at least one surface and pores, all or part of the friction coating (6) comprising a sealant (7) filling the pores formed between the asperities of the friction coating (6). [2] Clutch according to claim 1, wherein the sealing means (7) fills the pores of the friction coating (6) at a height extending from the lowest to the highest unevennesses. [3] Coupling according to one of the preceding claims, comprising an inner sleeve (4) having an inner surface (4a) intended to come into axial contact with the ends (2A, 3A) of the two shafts (2, 3) to be connected, and an outer sleeve (5) fixed around the inner sleeve (4), the friction coating (6) at least partially covering the inner surface (4a) of the inner sleeve (4). [4] A coupling according to claim 3, wherein the sealing means (7) is arranged at two spaced regions each positioned at one end of the inner sleeve (4), the sealing means covering each region in the circumferential direction. [5] Coupling according to claim 1 or 2, comprising an inner sleeve (10) with an inner surface (10a) intended to come into axial contact with one of the ends (2A, 3A) of the two shafts (2, 3) to be connected, and an outer sleeve (11) fixed around the inner sleeve (10), wherein the inner sleeve (10) or the outer sleeve (11) comprises a flange (12) having a radial surface (10b) intended to come into radial contact with a flange (9) of the other of the ends of the two shafts (2, 3) to be connected, wherein the friction coating (6) at least partially covers the inner surface (10a) of the inner sleeve (10) and / or the radial surface (10b) of the inner sleeve (10) or the outer sleeve (11). [6] Drive system comprising two rotating shafts and at least one clutch (1; 8) according to one of the preceding claims, wherein the friction coating (6) is in frictional engagement with at least one of the ends (2A, 3A) of the two rotating shafts (2, 3). [7] Method for manufacturing a clutch according to one of claims 1 to 5, comprising applying a sealant (7) to all or part of the friction coating (6) on at least one surface of the clutch intended to come into contact with the ends (2A, 3A) of the two shafts (2, 3). [8] Method according to claim 7, wherein the sealant (7) is applied by brushing, spraying or bathing. [9] Method according to claim 7 or 8, comprising a preparatory step of applying the friction coating (6) to the at least one surface of the clutch (1; 8) by thermal spraying.

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