Interface between two casings comprising a metal seal and a silicone seal

Abstract

The invention relates to an arrangement (2) comprising a first casing (10) which comprises a first opening (13) and a second casing (20) which comprises a second opening (23), an interface (30) comprising a first portion (31) which extends around the first opening (13) and around the second opening (23), the first opening (13) and the second opening (23) creating a tube (40) that passes through the first portion (31) of the interface (30), the tube (40) being intended to allow a pressurised liquid to flow, the first portion (31) of the interface (30) comprising a metal strip seal (50) so as to ensure sealing around the tube (40), the interface (30) comprising a second portion (32) joined to the first portion (31) of the interface (30), the second portion (32) of the interface (30) comprising a silicone seal (60) so as to ensure sealing of the second portion (32) of the interface (30).

Description

Description Title of the invention: Interface between two housings comprising a metal seal and a silicone seal.

[0001] The invention relates to an arrangement comprising a first housing and a second housing, and an interface extending between the two housings, the interface comprising a strip-type gasket and a silicone gasket. The invention further relates to a powertrain comprising such an arrangement. The invention also relates to a vehicle comprising such an arrangement or such a powertrain.

[0002] A hybrid or electric vehicle, particularly a motor vehicle, includes at least one electric motor. Such an electric motor typically comprises a shaft mounted to pivot relative to two housings joined together. This type of electric motor generally includes a liquid cooling system to optimize its cooling and / or warm-up. Consequently, the two joined housings of such a motor typically include at least one internal tube for the flow of coolant from one housing to the other, thus cooling each housing. These internal tubes are bulky and result in at least one radial protrusion on each of the two joined housings. This leads to a significant radial obstruction relative to the shaft axis of the electric motor at the location of this protrusion.

[0003] However, the engine compartment and / or the space for such an electric motor within such a vehicle, particularly a car, is generally cramped. Installing an electric motor in a car is therefore complex, given the other equipment that also needs to be accommodated. Thus, the radial protrusions on the casings, resulting from the installation of the cooling system for such an electric motor and / or an adjacent gearbox, increase its overall size and complicate the installation of the electric motor.

[0004] This situation is unsatisfactory. The radial dimensions of such an electric motor should be limited to facilitate its installation.

[0005] The objective of the present invention is to overcome the above-mentioned drawbacks. Furthermore, the invention ensures optimal sealing within a tube extending between two housings, even though this tube carries pressurized coolant. Summary of the invention

[0006] To achieve this objective, the invention relates to an arrangement comprising: - a first casing comprising a first opening and a second casing comprising a second opening, in particular a first casing intended to be arranged on the side of a gearbox and a second closing casing for an electric motor, - an interface comprising a first part extending around the first orifice and around the second orifice, the first orifice and the second orifice creating a tube passing through the first part of the interface, the tube being intended to allow the flow of a liquid under pressure, the first part of the interface comprising a metal strip type seal so as to ensure sealing around the tube, the interface comprising a second part attached to the first part of the interface, the second part of the interface comprising a silicone seal so as to ensure sealing of the second part of the interface.

[0007] The first housing may include a groove formed in a joint plane of the first housing and / or the second housing may include a groove formed in a joint plane of the second housing so as to accommodate the metal strip type gasket.

[0008] The thickness of the groove(s) and the thickness of the band-type joint can be equal or substantially equal, in particular being between 0.7 mm and 1.5 mm.

[0009] The metal strip type joint may include an extra thickness of compressible material, in particular a material having properties similar to those of rubber.

[0010] The extra thickness of the seal may include at least one bead extending around the first and second orifices in order to optimize the sealing of the tubing.

[0011] The arrangement may include at least one junction between the metal strip type joint and the silicone joint, the at least one junction being able to include an excess of silicone and / or the joint being able to include at least one non-straight edge so as to promote continuity of sealing between the metal strip type joint and the silicone joint.

[0012] At least one groove may include a clearance at the level of at least one junction between the two joints.

[0013] The first housing may include a centering pin within the first part of the interface and the second housing may include a bore within the first part of the interface cooperating with the centering pin, and / or the second housing may include a centering pin within the first part of the interface and the first housing may include a bore within the first part of the interface cooperating with the centering pin.

[0014] The invention further relates to a powertrain, in particular for a vehicle, in particular for a motor vehicle, comprising an arrangement as defined above.

[0015] The invention further relates to a vehicle, in particular a motor vehicle, comprising a powertrain as defined above, or an arrangement as defined above. Presentation of the figures

[0016] These objects, features and advantages of the present invention will be described in detail in the following non-limiting description of the embodiment, with reference to the accompanying figures, among which:

[0017] Figure [Fig. 1] is a schematic view of a vehicle according to one embodiment of the invention.

[0018] Figure 2 is a perspective view of an arrangement according to one embodiment of the invention.

[0019] Fig. 3 is a cross-sectional view along a plane passing through the axis of a shaft extending at least within a first housing and a second housing of the arrangement according to the embodiment of the invention.

[0020] Figure 4 is a front view of the second housing of the arrangement according to the embodiment of the invention.

[0021] Figure 5 is a detailed perspective view of the first housing of the arrangement according to the embodiment of the invention.

[0022] Figure 6 is a detailed front view of the second housing of the arrangement according to the embodiment of the invention.

[0023] Fig. 7 is a partial detail view at the level of an interface between the first housing and the second housing of the arrangement according to the embodiment of the invention.

[0024] Figure 8 is a detailed cross-sectional view of a metal strip type joint of the arrangement according to the embodiment of the invention. Detailed description

[0025] As schematically illustrated in [Fig. 1], a vehicle 1, preferably a motor vehicle, comprises a powertrain 5. The vehicle 1 or the powertrain 5 preferably comprises a gearbox 3. Preferably, the powertrain 5 comprises at least one electric motor 4. The powertrain 5 is, for example, hybrid or electric. The powertrain 5 or the vehicle 1 comprises an arrangement 2.

[0026] Arrangement 2 includes a first housing 10, illustrated in particular in Figures 2 and 3. The first housing 10 is, for example, intended to be arranged on the side of the box 3. The arrangement 2 includes a second housing 20. The second housing 20 is, for example, intended for closing the electric motor 4. The first housing 10 includes a joint surface 11. The second housing 20 includes a joint surface 21. Optionally, the arrangement 2 includes a shaft or axis 6 having an axis AP. The shaft 6 passes through the first housing 10 within a bore 7. The shaft 6 passes through the second housing 20 within a bore 8. Preferably, a bearing is provided at each bore 7, 8 so as to ensure a pivot connection between the shaft 6 and the housings 10, 20.

[0027] As illustrated in particular in [Fig.5], the first housing 10 includes a first orifice or hole or conduit 13. As illustrated in particular in Figures 4 and 6, the second housing 20 includes a second orifice or hole or conduit 23. The first orifice 13 and the second orifice 23 extend opposite each other, facing each other so that the first orifice 13 and the second orifice 23 together create a tube, a conduit 40 extending into the first and second housings 10, 20, as illustrated in [Fig.7].

[0028] Arrangement 2 still includes an interface 30 illustrated in particular on [Fig.3]. Interface 30 extends between the first housing 10 and the second housing 20. Interface 30 comprises a first portion 31 extending around the first orifice 13 and around the second orifice 23. The tube 40 passes through the first portion 31 of interface 30. The tube is designed to allow the passage, the flow, of a fluid, preferably a pressurized liquid. For example, the pressurized liquid flowing in the tube 40 is coolant.

[0029] Preferably, the first housing 10 includes a third orifice, hole, or conduit 18. As illustrated in particular in Figures 4 and 6, the second housing 20 includes a fourth orifice, hole, or conduit 28. The third orifice 18 and the fourth orifice 28 extend opposite each other, so that the third orifice 18 and the fourth orifice 28 together form a tube, a conduit 48 extending into the first and second housings 10 and 20. The tube 48 also passes through the first part 31 of the interface 30. The tube 48 is preferably also designed to allow the passage, the flow, of a fluid, preferably a pressurized liquid. For example, the pressurized liquid flowing in the tube 48 is also coolant.

[0030] In addition, other holes or conduits provided both in the first casing and in the second casing so as to create a tube passing through the first part 31 of the interface 30 may be provided.

[0031] As illustrated in Figures 4, 5, 6, and 7, the first part 31 of the interface 30 includes a metal strip-type gasket 50. This type of gasket ensures a seal around the pipe 40, and where applicable, around the pipe 48. By For example, gasket 50 has a composition similar to that of an internal combustion engine cylinder head gasket or dimple gasket. Preferably, gasket 50 is a steel strip gasket with or without an elastomer coating.

[0032] The interface 30 includes a second portion 32 attached to, bonded to, or in contact with the first portion 31 of the interface 30. Preferably, as illustrated in [Fig. 4] at the level of the second housing 20, the second portion 32 of the interface 30 extends over the remaining contact surface between the first housing and the second housing 20. The second portion 32 of the interface 30 includes a silicone seal 60. The seal 60 is silicone-based, contains silicone, or comprises a material having properties close to or identical to those of silicone. The seal 60 ensures the sealing of the second portion 32 of the interface 30, that is, the sealing between the mating surface 21 of the second housing 20 and the mating surface 11 of the first housing 10, outside the area whose sealing is ensured by the seal 50.

[0033] As illustrated in [Fig.5], the first housing 10 preferably includes a groove 15 formed in the joint plane 11 of the first housing 10. The groove 15 or groove or clearance includes a flat face 17 extending preferably parallel to the joint plane 11.

[0034] In addition or alternatively, as illustrated in [Fig.6], the second housing 20 includes a groove 25 formed in the joint plane 21 of the second housing 20. The groove 25 or groove or clearance includes a flat face 27 extending preferably parallel to the joint plane 21.

[0035] Advantageously, as illustrated in cross-section in [Fig. 8], the strip-type seal 50 includes an additional thickness 51 of compressible material. For example, the compressible material has properties similar to those of rubber, while also being heat-resistant. Preferably, as illustrated in Figures 5, 6, and 8, the additional thickness 51 of the joint 50 comprises at least one bead 52, preferably two bead 52, as illustrated, extends around the first orifice 13, and two beads 52 extend around the second orifice 23. In the case of a third orifice 18 provided in the first housing 10 and a fourth orifice 28 provided in the second housing 20, a bead, preferably two beads 52 as illustrated, extend around the third orifice 18, and two beads 52 extend around the fourth orifice 28. Note that a bead 52 surrounds, encircles, and surrounds the adjacent orifice, where it reinforces the seal. Note that a bead adjacent to another bead surrounding the same orifice extends at a distance from that bead without crossing that other bead. In other words, in the case of two beads 52 around the same orifice as illustrated, each bead constitutes a barrier preventing leakage between the seal 50 and the orifice that the bead surrounds.

[0036] The groove 15, or groove 25, or both grooves 15 and 25 as applicable, allows the strip-type gasket 50 to be housed, received, positioned, or accommodated between the two housings 10 and 20 at the first part 31 of the interface 30. For example, if only groove 15 is provided in the first housing 10, the thickness of groove 15 is equal to or substantially equal to the thickness of the gasket 50 in its mounted state between the two housings, i.e., compressed. For example, if only groove 25 is provided in the second housing 20, the thickness of groove 25 is equal to or substantially equal to the thickness of the gasket 50 in its mounted state between the two housings, i.e., compressed.

[0037] However, preferably, as illustrated in particular on [Fig.7], two grooves 15, 25 are provided respectively in the first housing 10 and in the second housing 20. The sum of the thicknesses or depths E15, E25 of the grooves 15, 25 is then equal, or substantially equal, to the thickness E50 of the seal 50 in the mounted state, assembled between the two housings, the two housings being clamped against each other by sandwiching the seal 50.

[0038] For example, the thickness of the metal strip type joint 50 is between 0.7 mm and 1.5 mm, or even between 0.9 mm and 1.2 mm, in the assembled, compressed state, that is to say when the ridges 52, or even part of the compressible overthickness 51, are compressed.

[0039] As illustrated in particular in [Fig. 6], the arrangement 2 includes at least one junction 55 between the strip-type gasket 50 and the silicone gasket 60. In the illustrated case, two junctions 55 are provided, one junction 55 extending from one side of the gasket 50 and the other junction 55 extending from the other side of the gasket 50. Indeed, the gasket 60 runs along the mating plane 11 of the first housing 10 or the mating plane 21 of the second housing 20, extending over the circumference of the mating plane to which it is applied, as illustrated in [Fig. 4]. Figures 4 and 6 illustrate the seal 60 after its application on the housing 20. Thus, the seal 60 "starts" from the seal 50 at the level of a junction 55 and "returns" to the seal 50 at the level of another junction 55, extending between the two joint planes 11, 21 on the second part 32 of the interface 30.

[0040] Preferably, each joint 55 includes an excess volume, a bulge, an excess 61 of silicone. The joint 50 then preferably includes a non-straight edge 53, for example, an edge 53 forming waves or ripples as illustrated in particular in [Fig. 6]. Thus, in the case of a joint 60 applied automatically by a machine, the machine takes a longer time at this point to create this excess 61 of material. In the case of manual application, similarly, more joint material is used to create these excesses near each edge 53.

[0041] Advantageously, each groove 15, 25 includes respectively a clearance, a cavity, a retention zone 16, 26 at each junction 55 between the two joints 50, 60. Note that each clearance 16 extends from an edge 151 of the groove 15 outwards from the groove 15 and that each clearance 26 extends from an edge 251 of the groove 25 outwards from the groove 25. Preferably, as illustrated in Figures 5 and 6, each edge 151, 251 of each groove 15, 25 is straight or substantially straight, and the clearances 16, 26 are convex, curved, and enlarge the corresponding groove. The clearances 16, 26 preferably extend to the boundary, to the limit, between the first part 31 of the interface 30 and the second part 32 of the interface 30, or even create the boundary between the first part and the second part of the interface 30.

[0042] Advantageously, a gap is provided between the two edges 151 of the groove 15 of the housing 10 and the seal 50. Similarly, where applicable, a gap is provided between the two edges 251 of the groove 25 of the housing 20 and the seal 50.

[0043] Thus each additional thickness or volume 61 of joint 60 is housed within each clearance 16, 26.

[0044] Preferably, as illustrated in figures 5 and 6, the first housing 10 includes at least one centering or positioning pin 12. The second housing 20 then includes at least one bore 22 cooperating with at least one centering pin 12.

[0045] Alternatively, or in addition, the second housing 20 includes at least one centering pin and the first housing 10 includes at least one bore cooperating with at least one centering pin.

[0046] For example, the distance D measured radially with respect to the main axis AP of the housings, between the tube 40 and the inside 19 of the first housing 10 and / or the inside 29 of the second housing 20, is between 3 mm and 10 mm, preferably on the order of 5 mm (see Figures 3 and 6). For example, the length L50 shown in [Fig. 8] is then equal to or approximately equal to the distance D. The length L50 is determined to minimize the gasket surface area, making the gasket 50 around each tube to obtain optimal sealing while limiting the radial size of the gasket 50.

[0047] In summary, the solution provides a static seal between the first and second housings along the entire interface 30 extending between the two housings 10, 20. The solution therefore involves an interface between two housings comprising a metal gasket and a silicone gasket. On the one hand, the gasket 50, made of metal strip covered with a compressible overlayer, provides sealing near the tube(s) 40, 48 passing through the first part 31 of the interface 30. On the other hand, the silicone gasket 60 provides sealing over the remainder of the interface 30, i.e., the second part 32. The junctions 55 between the two gaskets 50, 60 each have a geometry that allows for a reserve of silicone gasket material. In other words, the solution aims to implement a rigid, physical gasket 50 within a silicone gasket 60 between two parallel parts. As seen previously, the gasket 50 includes a The shape of the seal 50 is adapted to the path of the silicone seal that it cuts and intersects. Indeed, as illustrated in particular in Figures 5 and 6, the seal 50 preferably comprises two portions of non-straight edges 53, which may have wavy edges. These portions of non-straight edges promote, reinforce, and facilitate contact and adhesion of the silicone seal 60 to the seal 50 on its portions 53, and vice versa. The two recesses 16 provided at the end of the groove 15 and the two recesses 26 provided at the end of the groove 25, intended to be opposite the wavy edges 53 of the joint 50, offer space to accommodate more silicone sealant, namely the excess volumes or quantities 61 of the joint 60. These excesses 61 of silicone sealant combined with the wavy edges 53 and the receiving spaces for these excesses 61 provided by the notches 16, 26 in the grooves ensure the adhesion between the joints 50, 60.Thus, the solution ensures continuity, Injunction, of the seal between the strip type joint and the silicone joint.

[0048] The bead(s) 52 present in the compressible thickness 51 of the seal 50 and surrounding each tube 40, 48 at their connection between the two housings 10, 20 optimize and reinforce the sealing of each tube. Indeed, during assembly, the two housings 10, 20 are clamped together, which creates pressure on the entire interface 30 and therefore on the first part 31 of the interface 30, which includes the seal 50. As a result, at least the bead(s) 52, or even part of the thickness 51 of the seal 50, are compressed and flattened, thus strengthening the seal. Therefore, thanks to this solution, a high-pressure zone between the two housings is sealed. Preferably, the tubes 40, 48 carry pressurized coolant.

[0049] Above all, thanks to the compatibility created between seal 50 and seal 60, it becomes possible to create tubing with an oblong, flattened, or at least non-circular cross-section. This results in a radial space saving G, schematically illustrated in [Fig. 6], compared to tubing with a circular internal cross-section (shown in dotted lines). This radial gain within the tubing is reflected in the external dimensions of each housing, and ultimately, in the external dimensions of the assembly comprising the two housings. This results in space savings, for example, for the electric motor 4 and / or the gearbox 3, or even for the powertrain 5. All of this is made possible by the solution without reducing the internal cross-section of each tube 40, 48, and without affecting the coolant flow rate within these tubes.In other words, the cooling performance of the electric motor and / or gearbox is not affected. Furthermore, the solution improves sealing around the high-pressure lines by reducing the size of the housings containing these lines. This improves sealing reliability. allows increasing the lifespan of electric motors, for example so-called axial flux motors, by eliminating a risk of failure due to a sealing failure.

[0050] Thanks to the fact that the seal 50 is preferably housed in the two grooves 15, 25, its thickness is compensated for, specifically, only its compressible excess thickness 51 (in particular its ridges 52) protrudes from the grooves before the assembly and tightening of the two housings 10, 20 against each other. Advantageously, the silicone seal 60 has a very small, negligible thickness once the assembly is mounted and tightened.

[0051] Thus, thanks to this solution, it becomes possible to assemble the first housing 10 with the second housing 20 by interposing only the metal strip gasket 50 prior to machining the bores 7 and 8, in particular. In other words, the need for silicone sealant is eliminated for the machining operation(s). To guarantee the optimal coaxiality required for the installation of the shaft 6, the two bores 7 and 8 are generally machined in a single operation. For this purpose, the seal 50 is placed on the face 17 of the groove 15 of the first housing 10 so that the seal cooperates substantially with the pin 12 and / or with the straight edges 151 of the groove 15. Obviously, the seal 50 includes a hole 54 to allow the passage of the pin 12. Preferably, the hole 54 provided in the seal has a diameter just larger than the diameter of the pin so as to contribute to holding the seal in place.Similarly, preferably, the seal 50 comes into contact, or is nearly in contact, with each edge 151 of the groove 15 so as to hold the seal in position. Thus, the assembly of the housings 10, 20 with only the seal 50 interposed is facilitated by simultaneously positioning the seal against the pin and, where applicable, the edges of the groove 15. The housing(s) are then machined, and the two housings are subsequently separated. During final assembly, once elements such as the shaft 6 and any bearing means are arranged in the housing(s), the seal 50 is replaced, and the silicone sealant 60 is injected onto the second part 32 of the interface, for example, onto the second housing 20 only, as illustrated in [Fig. 4].

[0052] The solution saves time by eliminating the need to apply the silicone sealant during the machining stage. This would require removing the silicone sealant after machining before applying a new silicone sealant for the final assembly. However, silicone is pasty, sticky, slippery, and viscous, making it difficult to remove completely and properly, resulting in a long and tedious task.

[0053] The solution therefore makes it possible to achieve optimal sealing around orifices through which a high-pressure liquid passes between two joined housings which are machined together to limit the play related to the machining of the common shaft line.

[0054] The excess silicone sealant 60, provided at each junction 55 of the two seals, compresses and fills the recesses 16, 26, and grips the corrugations 53 of the seal 50 to create an optimal seal. High-pressure sealing around the ports 13, 23; 18, 28 is ensured by the seal 50, and low-pressure sealing at the second part 32 of the interface 30 between the two housings is ensured by the silicone.

[0055] The solution offers a radial space saving for both housings, making them easier to integrate within the engine compartment and / or the space designated for the electric motor in a vehicle, particularly a passenger car, despite limited available space. The sealing solution effectively reduces the size of the radial protrusions on the housings associated with the installation of the electric motor's cooling circuit and / or the adjacent gearbox.

[0056] Although two tubes were shown in the illustrated embodiment, more pressure tubes, or a single pressure tube, crossing the interface between two housings are possible.

[0057] Although only one metal strip type gasket is provided in the illustrated embodiment, several metal strip type gaskets can be arranged on the same interface between two housings, with silicone gaskets being arranged between the metal strip type gaskets.

[0058] As a point of note, the solution therefore achieves the desired objective of limiting the size of an electric motor while improving the sealing of tubes through which a high-pressure liquid flows, and has the advantage of being able to be used for other housing assemblies requiring a high-pressure seal adjacent to a low-pressure seal.

Claims

Demands

1. Arrangement (2) comprising: - a first housing (10) comprising a first opening (13) and a second housing (20) comprising a second opening (23), in particular a first housing (10) intended to be arranged on the side of a gearbox (3) and a second closing housing (20) for an electric motor (4), - an interface (30) comprising a first part (31) extending around the first orifice (13) and around the second orifice (23), the first orifice (13) and the second orifice (23) creating a tube (40) passing through the first part (31) of the interface (30), the tube (40) being intended to allow the flow of a liquid under pressure, the first part (31) of the interface (30) comprising a metal strip type seal (50) so as to ensure sealing around the tube (40), the interface (30) comprising a second part (32) attached to the first part (31) of the interface (30), the second part (32) of the interface (30) comprising a silicone seal (60) so as to ensure sealing of the second part (32) of the interface (30).

2. Arrangement (2) according to the preceding claim, characterized in that the first housing (10) includes a groove (15) formed in a joint plane (11) of the first housing (10) and / or the second housing (20) includes a groove (25) formed in a joint plane (21) of the second housing (20) so as to accommodate the metal strip type gasket (50).

3. Arrangement (2) according to the preceding claim, characterized in that the thickness (E15; E25) of the groove(s) (15; 25) and the thickness (E50) of the strip-type joint (50) are equal or substantially equal, in particular being between 0.7 mm and 1.5 mm.

4. Arrangement (2) according to any one of the preceding claims, characterized in that the metal strip type joint (50) comprises an overthickness (51) of compressible material, in particular of a material having properties similar to those of rubber.

5. Arrangement (2) according to the preceding claim, characterized in that the extra thickness (51) of the seal (50) includes at least one bead (52) extending around the first and second orifice (13, 23) so as to optimize the sealing of the tubing (40).

6. Arrangement (2) according to any one of claims 2 to 5, characterized in that the arrangement (2) comprises at least one junction (55) between the metal strip type gasket (50) and the silicone gasket (60), the at least one junction (55) comprising an excess volume (61) of silicone and / or the gasket (50) comprising at least one non-straight edge (53) so as to promote continuity of sealing between the strip type gasket and the silicone gasket.

7. Arrangement (2) according to the preceding claim in combination with claim 2, characterized in that at least one groove (15;25) includes a clearance (16;26) at the level of at least one junction (55) between the two joints (50, 60).

8. Arrangement (2) according to any one of the preceding claims, characterized in that the first housing (10) comprises a centering pin (12) within the first part (31) of the interface (30) and in that the second housing (20) comprises a bore (22) within the first part (31) of the interface (30) cooperating with the centering pin (12), and / or in that the second housing (20) comprises a centering pin within the first part (31) of the interface (30) and in that the first housing (10) comprises a bore within the first part (31) of the interface (30) cooperating with the centering pin.

9. Powertrain (5), in particular for a vehicle, in particular for a motor vehicle, comprising an arrangement (2) according to any one of the preceding claims.

10. Vehicle, in particular motor vehicle (1), comprising a powertrain (5) according to the preceding claim, or an arrangement (2) according to any one of claims 1 to 8.

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