Electrical sheath for a vehicle steering wheel

Abstract

Flexible electrical sheath (20) for vehicle steering wheel (10), comprising at least: - a first electrical conductor (21B), - a first flexible substrate (21A), - a second electrical conductor (22B), - a second flexible substrate (22A), and superimposed at least in part on the first flexible substrate (21A), wherein the first flexible substrate (21A) comprises at least a first folding notch (211) and the second flexible substrate (22A) comprises at least a second folding notch (221), characterized in that the first folding notch (211) is offset from the second folding notch (221), such that a first free edge (211L), of the first folding notch (211), is clear of the second flexible substrate (22A) and a second free edge (221L), of the second folding notch (221), is clear of the first flexible substrate (21A). Figure for the abridged version: Fig. 1

Description

Title of the invention: Electrical sheath for a vehicle steering wheel Technical field of the invention

[0001] The present invention relates generally to an electrical and / or composite sheath for a vehicle steering wheel, comprising a heating device and a device for detecting a human presence near or in contact with the steering wheel of a vehicle. The detection of contact with the steering wheel and the heating of the steering wheel can be carried out by the heating and detection devices of the electrical and / or composite sheath. State of the art

[0002] Detection devices are known in the prior art, such as that described in document EP3573349A1, comprising grooves to limit the compression zones and improve its assembly on a rigid support, and in particular its sheathing. In return, although this system does not include a heating device, making the adjustment even more sensitive by increasing the thickness to be sheathed, it does not systematically prevent the formation of folding defects. It can therefore be improved and adapted to thicker sheaths and / or steering wheel shapes that are more difficult to sheath without defects. Statement of the invention

[0003] An aim of the present invention is to address the drawbacks of the prior art mentioned above and in particular, first of all, to propose an electrical sheath, for example equipped with a heating device and a detection device, facilitating its assembly on the vehicle steering wheel, so as to avoid folds and / or allow regular and / or uniform closing of an external finishing sheath.

[0004] For this purpose, a first aspect of the invention may relate to a flexible electrical sheath for a vehicle steering wheel, comprising at least: - a first electrical conductor, - a first flexible substrate supporting the first electrical conductor, - a second electrical conductor, - a second flexible substrate supporting the second electrical conductor, and superimposed at least in part on the first flexible substrate, wherein the first flexible substrate may comprise at least one first folding notch and the second flexible substrate may comprise at least one second folding notch arranged at least partly opposite the first folding notch, characterized in that the first folding notch is offset from the second folding notch, such that a first free edge of the first folding notch is clear of the second flexible substrate and a second free edge of the second folding notch is clear of the first flexible substrate. According to the above implementation, the offsetting of the folding notches makes it possible to maximize the overlap of the second flexible substrate on the first, and to reduce the size of possible sheathing irregularities. Indeed, during sheathing on the rim of the vehicle steering wheel, at least one of the first free edge and / or the second free edge may cover a space between the edges respectively of the second folding notch or the first folding notch.

[0005] According to one embodiment, the first folding notch and / or the second folding notch may have a substantially triangular shape in top view.

[0006] According to one embodiment, in a state after assembly on the steering wheel, the first free edge of the first flexible substrate may be arranged at least partially opposite the second free edge of the second flexible substrate. There may then be an overlap which may avoid a hollow over the entire height (and / or thickness) of the electrical sheath.

[0007] According to one embodiment, the first flexible substrate may be attached to the second flexible substrate, preferably by an adhesive, the flexible electrical sheath comprising at least one free covering portion, adjacent to the first folding notch and / or to the second folding notch, in which the first flexible substrate is free relative to the second flexible substrate, and preferably the free covering portion may be free of adhesive between the first flexible substrate and the second flexible substrate. This free covering portion may make it possible to reduce the stress state in sheath portions that are particularly stressed during assembly, such that a manufacturing operator can adapt the shape of one of the substrates independently of the other substrate. Thus, the risks of creases in one or other of the substrates may be reduced.

[0008] According to one embodiment, the free overlap portion may cover an area along the first free edge, and / or the second free edge, which are the areas where folds are most likely to form. In other words, the free overlap portion may be an area where the first flexible substrate is opposite the second flexible substrate and may be an area delimited by a projection of the first free edge in a direction of the second free edge and by a projection of the second free edge in a direction of the first free edge.

[0009] According to one embodiment, the free covering portion may be an area in which a portion of the first flexible substrate faces the second flexible substrate.

[0010] According to one embodiment, the free covering portion may be a portion located less than 5 mm, preferably less than 4 mm, from an edge of the first folding notch and / or the second folding notch. The applicant noticed that the folds formed mainly in this area of ​​the sheath.

[0011] According to one embodiment, one of the first free edge of the first folding notch and the second free edge of the second folding notch may comprise an adhesive for attaching to the other of the first free edge of the first folding notch and the second free edge of the second folding notch when the flexible electrical sheath is in the state after assembly on the steering wheel. According to one embodiment, the other of the first free edge of the first folding notch and the second free edge of the second folding notch may be free of adhesive.

[0012] According to one embodiment, - the first free edge of the first folding notch can be released from the second flexible substrate over a first free area which extends up to at least 1 mm, preferably up to at least 2 mm, from the edge of the first folding notch and / or - the second free edge of the second folding notch can be released from the first flexible substrate over a second free area which extends up to at least 1 mm, preferably up to at least 2 mm, from the edge of the second folding notch.

[0013] According to one embodiment, - the first flexible substrate may be electrically insulating and is formed by a fabric, and / or by non-woven entangled fibers, and / or a foam, - the second flexible substrate may be electrically insulating and is formed by a fabric, and / or by non-woven entangled fibers, and / or a foam. Thus, electrical insulation between the electrical devices is guaranteed, which can ensure good detection accuracy and the absence of risks of short circuits.

[0014] According to one embodiment, the flexible electrical sheath may comprise a second secondary electrical conductor, wherein the second flexible substrate is arranged between the second electrical conductor and the second secondary electrical conductor. The detection device may therefore comprise a screen electrode and a detection electrode, which ensures good detection accuracy.

[0015] According to one embodiment, the flexible electrical sheath may comprise an adhesive, preferably a double-sided adhesive composite substrate (such as Scotch tape or double-sided tape), arranged at least partially: - between the first flexible substrate and the first electrical conductor, and / or - between the second flexible substrate and the second electrical conductor, and / or - between the first flexible substrate and the second flexible substrate, and / or - between the second flexible substrate and the first electrical conductor, and / or - on the first electrical conductor, and / or - on the second electrical conductor. This implementation can make it easy to assemble different layers of the sheath.

[0016] According to one embodiment, - the first flexible substrate and the first electrical conductor can form a vehicle steering wheel heating device, and - the second flexible substrate and the second electrical conductor can form a contact or proximity sensor for a user.

[0017] According to one embodiment, - the first electrical conductor can be glued and / or printed and / or sewn onto the first flexible substrate, and - the second electrical conductor can be glued and / or printed and / or sewn onto the second flexible substrate.

[0018] According to one embodiment, the first folding notch and the second folding notch may overlap to define a through notch of the flexible decorative sheath.

[0019] According to one embodiment, the through notch may have a first side adjacent to one of the first flexible substrate and the second flexible substrate and a second side adjacent to the other of the first flexible substrate and the second flexible substrate, and the first free edge may be arranged on the first side of the free notch, and the second free edge is arranged on the second side of the free notch. In other words, the first free edge and the second free edge may be arranged on either side of the through notch.

[0020] A second aspect of the invention may relate to a vehicle steering wheel, comprising: - a flexible electrical sheath according to the first aspect, - a decorative sheath, for example in leather, covering the flexible electrical sheath and visible to a user of the vehicle steering wheel.

[0021] According to one embodiment, the steering wheel may comprise a rim, a hub and at least one branch connecting the rim to the hub, in which the flexible electrical sheath covers at least part of the rim.

[0022] A third aspect of the invention may relate to a motor vehicle which may comprise a steering wheel according to the second aspect of the invention. In other words, this vehicle may comprise a steering wheel and in particular a flexible electrical sheath according to the first aspect of the present invention.

[0023] A fourth aspect of the invention may relate to a method of manufacturing a vehicle steering wheel according to the second aspect of the invention, comprising the steps following: - obtain a blank steering wheel, - provide a flexible electrical sheath according to the first aspect, - position the flexible electrical sheath on the steering wheel blank, - position the first free edge of the first flexible substrate at least partially opposite the second free edge of the second flexible substrate, - position the decorative sheath, for example in leather, and visible to a user of the vehicle steering wheel by covering the flexible electrical sheath.

[0024] According to one embodiment, the positioning of the first free edge of the first flexible substrate at least partially opposite the second free edge of the second flexible substrate may comprise the following steps: - adjusting a first edge of the first folding notch close to a second edge of the first folding notch, - adjusting the second free edge of the second folding notch above at least a portion of the first edge of the first folding notch and the second edge of the first folding notch. Description of figures

[0025] Other characteristics and advantages of the present invention will appear more clearly on reading the following detailed description of an embodiment of the invention given by way of non-limiting example and illustrated by the appended drawings, in which:

[0026] [Fig-1] schematically represents a front view of a vehicle steering wheel equipped with a flexible electrical sheath according to the present invention;

[0027] [Fig.2] shows a top view of the flexible electrical sheath for the steering wheel of vehicle of [Fig.l], before assembly and having folding notches according to the prior art and a folding notch according to the present invention;

[0028] [Fig.3] represents a detailed schematic sectional view of the electrical sheath flexible of an embodiment of the present invention;

[0029] [Fig.4] represents a schematic view of a folding notch according to the prior art;

[0030] [Fig.5] represents a schematic view of a folding notch according to the present invention;

[0031] [Fig.6] represents a schematic sectional view of the flexible electrical sheath after sheathing on the steering wheel of [Fig.l], along axis II of [Fig.4];

[0032] [Fig.7] represents a schematic sectional view of the flexible electrical sheath after sheathing on the steering wheel of [Fig.l], along axis II-II of [Fig.5].

[0033] Detailed description of embodiment(s)

[0034] [Fig.l] represents a steering wheel 10 of a vehicle, comprising a rim 11, spokes 12 and a hub 13. The rim 11 is typically equipped with a decorative external sheath covering a flexible electrical sheath 20 comprising a vehicle steering wheel heating device and a user contact or proximity sensor.

[0035] [Fig. 2] shows an overall view of the flexible electrical sheath 20 before assembly on the rim 11. Notches (otherwise called recesses) provided on the periphery of the flexible electrical sheath 20 allow a manufacturing operator to place the flexible electrical sheath 20 on the rim 11 to match the circular and rounded shape of the rim 11 without forming folds. The flexible electrical sheath 20 is connected to two connectors which supply it with the electricity necessary for the operation of the vehicle steering wheel heating device and the contact or proximity sensor of a user.

[0036] The folding notches formed on the periphery of the flexible electrical sheath 20 therefore make it possible to limit the formation of folds in the portions of the flexible electrical sheath 20 which must be compressed. Zone A represents a folding notch according to the prior art and zone B represents a folding notch according to the invention, as will be explained below.

[0037] [Fig. 3] represents a sectional view of the composite flexible electrical sheath 20 according to one embodiment: a heating device 21 and a contact or proximity sensor 22 are superimposed on each other.

[0038] In detail, the heating device 21 comprises a first electrical conductor 21B and a first flexible substrate 21A supporting the first electrical conductor 21B, and can make it possible to heat the steering wheel 10, thanks to the passage of an electric current in the first electrical conductor 21B.

[0039] The contact or proximity sensor 22 can make it possible to detect the presence of the user's hands on the steering wheel 10 using a capacitive device which detects capacitance variations induced by the human body. The contact or proximity sensor 22 can comprise a second electrical conductor 22B, a second secondary electrical conductor 22C, a second flexible substrate 22A supporting the second electrical conductor 22B and the second secondary electrical conductor 22C. It can be noted that the second secondary electrical conductor 22C (and therefore the adhesive 22D) is optional and can be omitted.

[0040] In this embodiment, the first electrical conductor 21B is deposited directly on the first flexible substrate 21A, for example by printing or sewing. However, it is possible to envisage fixing by double-sided adhesive. The second flexible substrate 22A can be attached to the second electrical conductor 22B and / or to the second secondary electrical conductor 22C, by a double-sided adhesive of reference 22E and 22D respectively. A final layer of adhesive 22F is attached to the second electrical conductor 22B to attach a decorative sheath thereto. It may be noted that the adhesive 22F is optional depending on the method chosen for attaching the decorative outer sheath. Similarly, the adhesive 22E may be omitted depending on the method chosen for bonding the second electrical conductor 22B to the second flexible substrate 22A.

[0041] It may be noted that the contact or proximity sensor 22 of the present invention is in no way limited to capacitive sensors but could refer to sensors of a different type such as thermal sensors, pressure sensors or silicon sensors producing for example a piezoelectric or thermoelectric effect.

[0042] The heating device 21 and the contact or proximity sensor 22 are positioned on top of each other also by a double-sided adhesive 21C. In the remainder of the description and the figures, only two layers will schematize the contact or proximity sensor 22 and the heating device 21.

[0043] [Fig.4] shows area A of [Fig.2] to represent a bending notch arranged in the superposition of the heating device 21 (white background) and the contact or proximity sensor 22 (hatched background) according to the prior art: a first folding notch (or a first indentation) 210 of the heating device 21 is superimposed on a second folding notch (or a second indentation) 220 of the contact or proximity sensor 22. For reasons of geometric manufacturing dispersions, the second folding notch 220 is larger than the first folding notch 210.

[0044] When assembling the flexible electrical sheath 20 on the rim 11, at the bending notch of zone A, the manufacturing operator can sheath the flexible electrical sheath 20 to make the lateral edges join together, in order to obtain an “edge-to-edge” sheathing. During this operation, the edges of the first bending notch 210 are practically joined, but can still remain distant from each other, as shown in [Fig. 6]. It can be noted [Fig. 6] that the edges of the contact or proximity sensor 22 are distant from each other, a consequence of the size of the second bending notch 220 being greater than the size of the first bending notch 210.Consequently, if the edges of the first folding notch 210 are significantly distant from each other, a hollow over the entire height or thickness Hd of the flexible electrical sheath 20 may be present and a decorative external sheath (made of leather for example) covering the rim 11 may have a hollow shape opposite this area, which may lead to a visual defect and the vehicle steering wheel being discarded.

[0045] [Fig.5] shows area B of [Fig.2] to represent a bending notch arranged in the superposition of the heating device 21 (white background) and the contact or proximity sensor 22 (hatched background) according to the invention: a first folding notch (or a first notch) 211 of the heating device 21 is superimposed on a second folding notch (or a second offset) 221 of the contact or proximity sensor 22. However, unlike [Fig. 4], the second folding notch 221 is offset from the first folding notch 211 so that a first free edge 21 IL of the first folding notch 211 is clear of the contact or proximity sensor 22 and a second free edge 22 IL of the second folding notch 221 is clear of the heating device 21. In the example shown here, the second folding notch 221 is offset from the first folding notch 211 in a direction tangential to the edge of the flexible electrical sheath 20.

[0046] The second folding notch 221 is shown larger than the first folding notch 211, but a similar or smaller size could be considered since the invention allows each folding notch edge to be adjusted when sheathing on the steering wheel as described below.

[0047] [Fig. 5] also shows an optional free overlap portion 23, delimited by straight lines originating from the first free edge 21 IL, from the second free edge 22 IL, and their parallels passing through the top of the second folding notch 221. In particular, this portion does not include adhesive: the heating device 21 and the contact or proximity sensor 22 can deform independently of each other in this free overlap zone 23.

[0048] When assembling the flexible electrical sheath 20 on the rim 11, at the bending notch of zone B, the manufacturing operator can sheath the flexible electrical sheath 20 to make the lateral edges join, in order to obtain an “edge-to-edge” sheathing. During this operation, the edges of the first bending notch 211 are practically joined, but can still remain distant from each other, as shown in [Fig. 7]. However, it can be noted [Fig. 7] that although the edges of the contact or proximity sensor 22 are distant from each other, the first free edge 21 IL and the second free edge 221L are opposite each other, so that the free space between two edges has only a height or a thickness of the contact or proximity sensor 22 at most.

[0049] Consequently, during subsequent sheathing with the outer sheath, the latter cannot deform over the entire height of the flexible electrical sheath 20, but only over the height of one of the layers of the flexible electrical sheath 20, i.e. according to the height (i.e. the thickness) of the contact or proximity sensor 22 or of the heating device 21 (depending on the mounting direction). Preferably, the thinnest element is arranged under the outer sheath to minimize the risk of appearance defects. Generally, the contact or proximity sensor 22 is arranged between the outer sheath and the heating device 21. The maximum height or thickness of the defect Hd of [Fig. 7] is much lower than the maximum height or thickness of the defect Hd of [Fig. 6].

[0050] It will be understood that various modifications and / or improvements obvious to those skilled in the art can be made to the different embodiments of the invention described in the present description without departing from the scope of the invention. In particular, it can be noted that the folding notches have a triangular shape (with an angular or rounded apex), but other cutting shapes can be envisaged to avoid compression folds.

[0051] In the example given, the flexible electrical sheath 20 comprises two layers formed by two electrical devices (one for heating and one for contact detection), but it is possible to envisage that each layer comprises several distinct electrical devices, of the same nature or different. It is possible to envisage overlaps, it is possible to envisage more than two layers, locally or over the entire flexible electrical sheath 20.

[0052] It is possible to envisage that the flexible electrical sheath covers other parts of the steering wheel, such as for example the branches 12.

[0053] It is possible to envisage that the free face of the first free edge 21 IL and / or of the second free edge 22IL is covered with an adhesive with a protective layer or sheet to be removed at the last moment during the sheathing or after the latter, to properly secure the configuration of [Fig.7]. Indeed, during installation on the steering wheel, the operator could remove the protective layer or sheet from the first free edge 21 IL and / or from the second free edge 22IL to stick the first free edge 21 IL on the second free edge 22IL. Industrial application

[0054] A flexible electrical sheath according to the present invention, and its manufacture, are capable of industrial application.

Claims

Claims

1. Flexible electrical sheath (20) for a vehicle steering wheel (10), comprising at least: - a first electrical conductor (21B), - a first flexible substrate (21A) supporting the first electrical conductor (21B), - a second electrical conductor (22B), - a second flexible substrate (22A) supporting the second electrical conductor (22B), and superimposed at least in part on the first flexible substrate (21A), in which the first flexible substrate (21A) comprises at least a first folding notch (211) and the second flexible substrate (22A) comprises at least a second folding notch (221) arranged at least in part opposite the first folding notch (211), characterized in that the first folding notch (211) is offset from the second folding notch (221), so that a first free edge (211L), of the first folding notch (211), is clear of the second flexible substrate (22A) and a second free border (221L),of the second folding notch (221), is released from the first flexible substrate (21A).,

2. Flexible electrical sheath (20) according to claim 1, wherein, in a state after assembly on the steering wheel (10), the first free edge (21 IL) of the first flexible substrate (21A) is arranged at least partially opposite the second free edge (22IL) of the second flexible substrate (22A).

3. A flexible electrical sheath (20) according to claim 1 or 2, wherein the first flexible substrate (21A) is attached to the second flexible substrate (22A), preferably by an adhesive (21C), the flexible electrical sheath (20) comprising at least one free covering portion (23), adjacent to the first folding notch (211) and / or the second folding notch (221), wherein the first flexible substrate (21A) is free relative to the second flexible substrate (22A), and preferably the free covering portion (23) is free of adhesive (21C) between the first flexible substrate (21A) and the second flexible substrate (22A).

4. Flexible electrical sheath (20) according to claim 3 in which the free covering portion (23) covers an area along the first free edge (21 IL), and / or the second free edge (221L).

5. Flexible electrical sheath (20) according to claim 3 or 4 in which the free covering portion (23) is an area in which a portion of the first flexible substrate (21A) faces the second flexible substrate (22A).

6. Flexible electrical sheath (20) according to one of claims 3 to 5, in which the free covering portion (23) is a portion located less than 5 mm, preferably less than 4 mm, from an edge of the first folding notch (211) and / or the second folding notch (221).

7. The flexible electrical sheath (20) according to one of claims 1 to 6, wherein one of the first free edge (21 IL) of the first folding notch (211) and the second free edge (22IL) of the second folding notch (221) comprises an adhesive (21C) for attaching to the other of the first free edge (21 IL) of the first folding notch (211) and the second free edge (22IL) of the second folding notch (221) when the flexible electrical sheath (20) is in the state after assembly on the steering wheel (10).

8. Flexible electrical sheath (20) according to one of claims 1 to 7, wherein: - the first free edge (21 IL) of the first folding notch (211) is clear of the second flexible substrate (22A) over a first free area which extends up to at least 1 mm, preferably up to at least 2 mm, from the edge of the first folding notch (211) and / or - the second free edge (22IL) of the second folding notch (221) is clear of the first flexible substrate (21A) over a second free area which extends up to at least 1 mm, preferably up to at least 2 mm, from the edge of the second folding notch (221).

9. Flexible electrical sheath (20) according to one of claims 1 to 8, in which: - the first flexible substrate (21A) is electrically insulating and is formed by a fabric, and / or by non-woven entangled fibers, and / or a foam, - the second flexible substrate (22A) is electrically insulating and is formed by a fabric, and / or by non-woven entangled fibers, and / or a foam.

10. Flexible electrical sheath (20) according to one of claims 1 to 9, comprising a second secondary electrical conductor (22C), in wherein the second flexible substrate (22A) is arranged between the second electrical conductor (22B) and the second secondary electrical conductor (22C).

11. Flexible electrical sheath (20) according to one of claims 1 to 10, comprising an adhesive (21C, 22D, 22E), preferably a double-sided adhesive composite substrate, arranged at least partially: - between the first flexible substrate (21A) and the first electrical conductor (21B), and / or - between the second flexible substrate (22A) and the second electrical conductor (22B), and / or - between the first flexible substrate (21A) and the second flexible substrate (22A), and / or - between the second flexible substrate (22A) and the first electrical conductor (21B), and / or - on the first electrical conductor (21B), and / or - on the second electrical conductor (22B).

12. Flexible electrical sheath (20) according to one of claims 1 to 11, in which: - the first flexible substrate (21A) and the first electrical conductor (21B) form a heating device (21) for the vehicle steering wheel (10), and - the second flexible substrate (22A) and the second electrical conductor (22B) form a contact or proximity sensor (22) for a user.

13. Flexible electrical sheath (20) according to one of claims 1 to 12, in which: - the first electrical conductor (21B) is glued and / or printed and / or sewn onto the first flexible substrate (21A), and - the second electrical conductor (22B) is glued and / or printed and / or sewn onto the second flexible substrate (22A).

14. Vehicle steering wheel (10), comprising: - a flexible electrical sheath (20) according to one of claims 1 to 13, - a decorative sheath, for example made of leather, covering the flexible electrical sheath (20) and visible to a user of the vehicle steering wheel (10).

15. A vehicle steering wheel (10) according to claim 14, comprising a rim (11), a hub (13) and at least one branch (12) connecting the rim (11) to the hub (13), wherein the flexible electrical sheath (20) covers at least less part of the rim (11).

16. Motor vehicle comprising a vehicle steering wheel (10) according to one of claims 14 or 15.

17. Method for manufacturing a vehicle steering wheel (10) according to one of claims 14 or 15, comprising the following steps: - providing a steering wheel blank (10), - providing a flexible electrical sheath (20) according to one of claims 1 to 13, - positioning the flexible electrical sheath (20) on the steering wheel blank (10), - positioning the first free edge (21 IL) of the first flexible substrate (21 A) at least partially opposite the second free edge (221L) of the second flexible substrate (22A), - positioning the decorative sheath, for example made of leather, and visible to a user of the vehicle steering wheel (10) by covering the flexible electrical sheath (20).

18. Manufacturing method according to claim 17, wherein the positioning of the first free edge (21 IL) of the first flexible substrate (21 A) at least partially opposite the second free edge (221L) of the second flexible substrate (22A) comprises the following steps: - adjusting a first edge of the first folding notch (211) close to a second edge of the first folding notch (211), - adjusting the second free edge (22IL) of the second folding notch (221) above at least a portion of the first edge of the first folding notch (211) and the second edge of the first folding notch (211).

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