Deformation measuring device

Abstract

Strain Measurement Device This description relates to a strain measurement device (100), comprising at least: - a strain sensor (102) comprising at least one portion of piezoelectric material less than 50 µm thick, attached to a first portion (104) of a flexible support (106); - a housing (114) to which a second portion (108) of the flexible support (106) is mechanically attached; - a connecting cable (120) comprising a first end electrically coupled to a connector (122) and a second end (124) mechanically attached to the housing (114); and wherein the second end (124) of the connecting cable (120) is electrically coupled to the strain sensor (102) by at least one connection disposed in the housing (114). Figure for the abbreviation: Fig. 1

Description

Title of the invention: Deformation measuring device technical field

[0001] This description relates generally to the field of deformation measurement, for example vibration measurement to assess, for example, stresses, or fatigue of a part or part of a system, or the vibration of a system, particularly in an industrial environment, such as vibration measurement on industrial machines. Previous technique

[0002] Monitoring industrial machines such as machine tools can be carried out by measuring deformations, for example vibrations, produced by these machines. The sensors used for this type of monitoring must meet several constraints, such as having connectors adapted to industrial standards, being robust, having good sealing, offering sufficient protection against electromagnetic interference, etc.

[0003] Piezoelectric crystal accelerometers can be used as strain sensors for this type of monitoring. However, these accelerometers are bulky and difficult to integrate. They cannot be placed close to potential sources of vibration and therefore do not provide a very precise measurement. Furthermore, these accelerometers do not provide direct access to the physical measurement of strain but measure an acceleration that must be integrated twice successively to first obtain a displacement, and then a model of the monitored part must be used to determine the strain. This results in significant inaccuracy in the strain measurement. These accelerometers are not very effective at measuring low-frequency events, which are critical for assessing the stresses and fatigue of the parts in a system.

[0004] Another solution involves using strain gauges. These gauges are housed in rigid casings or mounted on rigid brackets that are screwed onto the machines whose vibrations are being measured. However, such casings or brackets must be fixed to flat surfaces, which precludes taking these measurements on non-planar surfaces. Furthermore, the measurements obtained are not very precise.

[0005] Similar problems also arise when piezoelectric gauges are used in bulky rigid housings.

[0006] These disadvantages are also found in areas other than that of monitoring deformations, for example vibrations, of industrial machines. Summary of the invention

[0007] There is a need to propose a deformation measurement device that does not present the problems posed by existing devices.

[0008] One embodiment overcomes all or part of the drawbacks of known devices and provides a deformation measurement device, comprising at least:

[0009] - a strain sensor comprising at least a portion of material piezoelectric whose thickness is less than 50 pm and which is attached to a first part of a flexible support;

[0010] - a housing to which a second part of the support is mechanically attached flexible ;

[0011] - a connecting cable comprising a first end electrically coupled to a connector and a second end mechanically attached to the housing;

[0012] and wherein the second end of the connecting cable is electrically coupled to the deformation sensor by at least one connection disposed in the housing.

[0013] According to a particular embodiment, the deformation measurement device further comprises at least one electronic measurement acquisition circuit configured to receive and process a measurement signal intended to be delivered by the deformation sensor, disposed in the housing and electrically coupled to the deformation sensor and to the second end of the connection cable.

[0014] According to a particular embodiment, the electronic circuit is secured to the second part of the flexible support.

[0015] According to a particular embodiment, the second part of the flexible support is mechanically attached to the housing, and the device includes at least one resin covering the second part of the flexible support and hermetically sealing the housing by filling at least one cavity of the housing in which at least the second part of the flexible support is disposed.

[0016] According to a particular embodiment, said at least one connection comprises at least one weld between at least one conductor wire of the connecting cable and at least one connection pad disposed on the second part of the flexible support.

[0017] According to a particular embodiment, the housing is rigid and metallic.

[0018] According to a particular embodiment, the connecting cable comprises a shielding braid arranged between at least one conductor wire and a sheath of the connecting cable and electrically coupled to the housing.

[0019] According to a particular embodiment, the second end of the connecting cable is mechanically secured to the housing by at least one fixing screw disposed in a hole formed in the housing, the hole comprising an open side opening into an opening through a wall of the housing and into which the second end of the connecting cable is inserted, an axis of the hole being perpendicular to an axis of the opening, at least one threaded part of the fixing screw being screwed laterally into a sheath of the connecting cable at an intersection between a volume of the hole and a volume of the opening.

[0020] According to a particular embodiment, the fixing screw is electrically conductive and ensures electrical contact between the shielding braid and the housing.

[0021] According to a particular embodiment, the flexible support forms a ribbon extending from its first part to its second part.

[0022] According to a particular embodiment, the portion of piezoelectric material comprises a piezoceramic material.

[0023] A method for implementing a deformation measurement device is also proposed, comprising at least:

[0024] - realization of a strain sensor comprising at least a portion of piezoelectric material whose thickness is less than 50 pm and which is bonded to a first part of a flexible support;

[0025] - mechanical fastening of a second end of a connection cable to a case;

[0026] - mechanical fastening of a second part of the flexible support to the housing;

[0027] - making at least one connection between the second end of the cable connection and strain sensor in the housing, the connection cable also including a first end to which a connector is electrically coupled.

[0028] According to a particular embodiment, the mechanical fastening of the second part of the flexible support to the housing comprises a dispensing of at least one resin in at least one cavity of the housing in which at least the second part of the flexible support is disposed, hermetically sealing the housing.

[0029] According to a particular embodiment, the mechanical fastening of the second end of the connecting cable to the housing comprises screwing at least one fixing screw into a hole formed in the housing and comprising an open side leading into an opening through a wall of the housing and into which the second end of the connecting cable is inserted, an axis of the hole being perpendicular to an axis of the opening, such that at least one threaded part of the fixing screw is screwed into a sheath of the connecting cable at the level of an intersection between a volume of the hole and a volume of the opening. Brief description of the drawings

[0030] These features and advantages, as well as others, will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the accompanying figures, among which:

[0031] - Fig. 1 schematically represents an exploded perspective view of a deformation measurement device according to a particular embodiment;

[0032] - Figure 2 schematically represents a perspective view of a device measurement of deformation according to a particular embodiment;

[0033] - Figure 3 schematically represents a perspective view of part of a deformation measurement device according to a particular embodiment;

[0034] - Figure 4 schematically represents a cross-sectional view of part of a device deformation measurement according to a particular embodiment;

[0035] - Figure 5 schematically represents a cross-sectional view of part of a device deformation measurement according to a particular embodiment. Description of the implementation methods

[0036] The same elements have been designated by the same reference numerals in the different figures. In particular, the structural and / or functional elements common to the different embodiments may have the same reference numerals and may have identical structural, dimensional and material properties.

[0037] For the sake of clarity, only the steps and elements useful for understanding the described embodiments have been represented and are detailed.

[0038] Unless otherwise specified, when referring to two elements connected together, this means directly connected without intermediate elements other than conductors, and when referring to two elements linked or coupled together, this means that these two elements can be connected or linked through one or more other elements.

[0039] In the following description, when reference is made to absolute position qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative position qualifiers, such as the terms "above", "below", "superior", "inferior", etc., or to orientation qualifiers, such as the terms "horizontal", "vertical", etc., reference is made, unless otherwise specified, to the orientation of the figures in a normal position of use.

[0040] Unless otherwise specified, the expressions "approximately", "roughly", and "in the order of" mean within 10%, preferably within 5%.

[0041] An example of a deformation measuring device 100 is described below with reference to Figures 1 and 2, each representing the entire device 100, in the form of unassembled elements in [Fig. 1] and in the form of elements assembled together on [Fig.2]. In addition, figures 3 to 5 represent in more detail certain elements of device 100.

[0042] The device 100 includes a strain sensor 102 comprising at least one portion of piezoelectric material with a thickness of less than 50 pm, preferably less than 25 pm, and even more preferably less than 10 pm. For example, the value of the ratio between the thickness (dimension parallel to the Z-axis in the figures) and the width (dimension parallel to the Y-axis in the figures), and / or between the thickness and the length (dimension parallel to the Z-axis in the figures), of this portion of piezoelectric material is, for example, less than 0.1, preferably less than 0.05, and even more preferably less than 0.01.

[0043] According to a particular embodiment, the portion of piezoelectric material of the sensor 102 comprises at least one piezoceramic material, for example PZT (lead zirconate titano), or LiNbO3 (lithium niobate), or LiTaO3 (lithium tantalate). Other piezoelectric materials are also conceivable for the production of the piezoelectric material portion of sensor 102, such as BaTiO3 (barium titanate), PbTiO3 (lead titanate), KNbO3 (potassium niobate), NBT (NaO3Bi()3TiO3 or sodium bismuth titanate), BiFeO3 (bismuth ferrite), ZnO (zinc oxide), PAIN (aluminum nitride) or BNT (BiO25NaO25TiO3 or sodium bismuth titanate) or a crystal such as quartz, or even a polymer piezoelectric material such as PVDF.

[0044] Other details of the realization of such a sensor 102 are described for example in the document by T.Dufay et al., “Flexible PZT thin film transferred on polymer substrate”, Surface and Coatings Technology, Elsevier, 2018, 343, pp. 148-152.

[0045] The portion of piezoelectric material of the sensor 102 can be arranged between a first electrode intended to receive a reference electrical potential, and a second electrode on which a measurement signal is intended to be delivered by the sensor 102. These electrodes are not shown in the figures.

[0046] The sensor 102 is disposed on, and secured to, a first part 104 of a flexible support 106, or flexible support, which, in the example described, forms a first end part of the flexible support 106. The flexible support 106 also includes a second part 108 which, in the example described, forms a second end part of the flexible support 106 opposite to the first end part.

[0047] In the described example, the flexible support 106 forms a ribbon extending from its first part 104 to its second part 108. In the described example, the flexible support 106 includes, between the first and second parts 104, 108, a third part 110 in the form of meanders, providing additional freedom to the support 106. Regarding its positioning, particularly in the (X,Y) plane in which the ribbon formed by the flexible support 106 extends, this third portion 110 allows the flexible support 106 to withstand radii of curvature, for example, greater than or equal to 2 mm, without damage to the flexible support 106. In the example described, the flexible support 106 also includes, between the second and third portions 108 and 110, a fourth portion 111 that is straight and extends parallel to the X-axis.

[0048] Alternatively, the flexible support 106 may not include at least one of the third and fourth parts 110, 111, and thus be shorter than in the example shown in the figures, the first part 104 being in this case directly adjacent to the second part 108 of the flexible support 106. Other embodiments of the flexible support 106 are possible.

[0049] By way of example, the flexural stiffness D of the flexible support 106, which can form a composite multilayer, can be expressed by the equation:

[0050] D ~ (Eeq*htot3) / 12, neglecting Poisson's coefficients.

[0051] with Eeq corresponding to the equivalent modulus of elasticity of the flexible support 106, and htot corresponding to the total thickness of the flexible support 106.

[0052] Considering that the flexible support 106 comprises polyimide with a modulus of elasticity Epoiyimide of approximately 2.5 GPa, and copper with a modulus of elasticity ECu of approximately 110 GPa, the equivalent modulus of elasticity of the flexible support 106 Eeq is approximately 27.3 GPa. Furthermore, considering that the thickness of the polyimide hpoiyimide is approximately 0.120 mm and that the thickness of the copper layers hCu is approximately 2*0.018 mm, the total thickness of the flexible support 106 htot is approximately 0.156 mm. Thus, the flexural stiffness D of the flexible support 106 is, in this example, approximately 8.64 MPa.mm3.

[0053] More generally, the flexural stiffness D of the flexible support 106 can be less than 50 MPa-mm3, or even advantageously less than 30 MPa-mm3, and more advantageously less than 10 MPa-mm3.

[0054] In the described example, the device 100 further comprises at least one electronic measurement acquisition circuit 112 configured to receive and process a measurement signal intended to be delivered by the sensor 102. In the figures, the electronic circuit 112 is attached to the second part 108 of the flexible support 106. Moreover, in the example shown in Figures 1 to 3, the sensor 102 is arranged on one face of the flexible support 106, while the electronic circuit 112 is arranged on a second face of the flexible support 106, which is opposite the first face. In this embodiment, the electronic circuit 112 corresponds to an IEPE (“Integrated Electronics Processing Element”) circuit. Piezo-Electric Electronics (in English). The electronic circuit 112 includes electronic components implementing various signal processing functions for the measurement signals delivered by the sensor 102, for example amplification, filtering, analog-to-digital conversion, etc.

[0055] The device 100 also includes a housing 114 to which the flexible support 106 is mechanically attached. In the example described, the housing 114 forms a cover and has a cavity 116 in which, among other things, the second part 108 of the flexible support 106 and the electronic circuit 112 are arranged in order to protect them mechanically. In the example described, the housing 114 is rigid and metallic, for example, made of stainless steel. Alternatively, the housing 114 may be made of other types of materials. Furthermore, in the example described, the housing 114 has a general rectangular prism shape. Other shapes are, however, possible. By way of example, the dimensions of the housing 114 (length parallel to the X-axis, width parallel to the Y-axis, thickness parallel to the Z-axis) are each between 1 mm and 10 cm.In the example described, holes 113 are made in two corners of the housing 114 to allow the housing 114 to be screwed against a mounting surface.

[0056] In the described example, the flexible support 106 is mechanically attached to the housing 114. A resin 118 covers the second part 108 of the flexible support 106 and hermetically seals the cavity 116 of the housing 114 by filling the space in the cavity 116 not occupied, in particular, by the electronic circuit 112 and the second part 108 of the flexible support 106. The resin 118 thus contributes, together with the housing 114, to the protection of the electronic circuit 112. The resin 118 may, for example, contain epoxy. The level of protection obtained thanks to the housing 114 and the resin 118 can comply with the IP68 level as defined by the EN 60529 standard. In [Fig.2], the second part 108 of the flexible support 106 is symbolically represented by transparency through the resin 118 although this second part 108 is actually embedded in the resin 118.

[0057] The device 100 also includes a connecting cable 120 comprising a first end to which a connector 122 is electrically coupled and a second end 124 mechanically attached to the housing 114. For example, the cable 120 and the connector 122 may be of industrial grade, i.e., conforming to industrial standards. For example, the connector 122 may be type M12 as defined by IEC 61076-2-101 or IEC 61076-2-010. The cable 120 may have a diameter of, for example, 5 mm and a length of, for example, a few tens of centimeters.

[0058] Although not visible in Figures 1 and 2, the second end 124 of the cable 120 is electrically coupled to the sensor 102 by one or more electrical connections arranged in the cavity 116 and protected by the resin 118, which fills the free space of the cavity 116 and thus encapsulates this or these electrical connections. According to one embodiment, this or these electrical connections may include solder joints between one or more conductive wires 121 of the cable 120, for example, four conductive wires 121 as shown in [Fig. 4], and one or more connection pads (not shown in the figures) arranged on the second part 108 of the flexible support 106. In the example described, this or these connection pads are electrically coupled to the electronic circuit 112.Alternatively, this electrical connection between the conductor wire(s) 121 of the cable 120 and the electronic circuit 112 could be made via male-female connectors, one of these connectors being coupled to the second end 124 of the cable 120 and the other connector being disposed on the second part 108 of the flexible support 106 and electrically coupled to the electronic circuit 112.

[0059] In the described example, the electronic circuit 112 is electrically coupled to the sensor 102 and to the second end 124 of the cable 120. Thus, the electronic circuit 112 ensures the reception or reading of the measurement signals from the sensor 102, the processing of these measurement signals (for example amplification, filtering, analog-to-digital conversion, etc.), and then their transmission on the conductive wires 121 of the cable 120.

[0060] Alternatively, the electronic circuit 112 may not be arranged on the second part 108 of the flexible support 106, but may be arranged directly in the cavity 116 of the housing 114. In this case, one or more additional electrical connections may be formed between the electronic circuit 112 and conductive elements present on the second part 108 of the flexible support 106, this or these additional electrical connections being arranged in the cavity 116 of the housing 114 and protected by the resin 118.

[0061] In the example described, the cable 120 also includes a shielding braid 123 arranged between the conductor wire(s) 121 and a sheath 125 of the cable 120. The use of a metallic housing 114 allows the shielding braid 123 to be electrically coupled to the housing 114. The housing 114 thus contributes to the electromagnetic protection of the elements present in the cavity 116 as well as of the signals transmitted by the electronic circuit 112 to the cable 120.

[0062] In the described example, the second end 124 of the connecting cable 120 is mechanically secured to the housing 114 by a fixing screw 126 disposed in a hole 128 formed in the housing 114, corresponding, for example, to a tapped hole. The hole 128 has an open side leading into a through opening 130 a wall of the housing 114 into which the second end 124 of the cable 120 is inserted. The hole 128 has an axis perpendicular to an axis of the opening 130. The mechanical retention of the cable 120 to the housing 114 is achieved by the fact that a threaded portion of the fixing screw 126 is screwed laterally into the sheath 125 of the cable 120 at an intersection between the volume of the hole 128 and the volume of the opening 130. Details of these elements and this fixing are visible in Figures 3 to 5, which show these elements in perspective and in section.

[0063] Furthermore, in the described example, the fixing screw 126 also ensures, in addition to the mechanical retention of the cable 120 to the housing 114, an electrical contact between the shielding braid 123 of the cable 120 and the housing 114. This electrical contact is achieved because the depth to which the fixing screw 126 is inserted laterally into the sheath 125 of the cable 120 allows the screw 126 to be in electrical contact with the shielding braid 123. Since the screw 126 is in contact with the walls of the hole 128, which are electrically conductive when the housing 114 is metallic, the shielding braid 123 becomes electrically coupled to the housing 114. Thus, when the housing 114 is fixed against an electrically conductive surface, the housing 114 forms the electrical ground for the electronic circuit 112 as well as electromagnetic protection for the components arranged in cavity 116 of housing 114.

[0064] In the example described, the shapes, positions, and dimensions of the hole 128 and the opening 130, as well as the shape and dimensions of the screw 126, are chosen so that the screw 126 is driven laterally into the sheath 125 of the cable 120 and makes electrical contact with the shielding braid 123 without, however, reaching the conductor wire(s) 121 of the cable 120 and without creating a short circuit with this or these wire(s) 121. The characteristics of the hole 128, the opening 130, and the screw 126 can therefore be chosen according to the characteristics of the cable 120 used, in particular the thickness of the cable sheath 120 and the depths at which the shielding braid 123 and the conductor wire(s) 121 are located in the cable 120.

[0065] To construct the device 100 according to the example described above, the sensor 102 and the electronic circuit 112 can first be mounted on the flexible support 106. The second end 124 of the cable 120 is inserted into the opening 130 and mechanically secured to the housing 114 by screwing the screw 126 into the hole 128, also ensuring electrical contact between the housing 114 and the shielding braid 123 of the cable 120. The electrical connections between the conductor wires of the cable 120 and the electronic circuit 112 are made, with the second part 108 of the flexible support 106, on which the electronic circuit 112 is mounted, being placed in the cavity 116 of the housing 114. The cavity 116 is then closed by filling it with the resin 118.

[0066] The device 100 is fixed to the surface of the element for which deformations are to be measured, for example by gluing and / or screwing. For example, The housing 114 can be glued and / or screwed onto this surface, and the flexible support 106 can be glued onto this surface such that the sensor 102 is positioned precisely at the desired location for measuring deformations. The flexibility of the flexible support 106 allows the sensor 102 to be precisely glued to the desired location, even if the surface on which the deformations are to be measured is not flat.

[0067] The device 100 can be advantageously used for vibration monitoring of industrial machines such as numerically controlled (CNC) machine tools, for example, precision machining tools. In the described embodiment, the device 100 can be connected, via cable 120, to a network to which one or more industrial machines are connected by a programmable logic controller (PLC).Device 100 can be used to measure deformations continuously or at regular or irregular intervals. The device can also be used to detect deformations such that an output signal is generated when the measured deformations exceed a certain threshold value. Alternatively, device 100 can be used to detect or measure a deformation, such as vibrations, of an element other than a machine, such as a structure, infrastructure, etc.

[0068] The device 100 is well suited to detect different types of deformations or vibrations, from small deformations changing rapidly to large slow deformations.

[0069] Thanks to the thin portion of piezoelectric material used, the sensor 102 of the device 100 exhibits a uniform frequency response, good sensitivity, and good measurement accuracy. Furthermore, the portion of piezoelectric material in the sensor 102 is thin enough to allow the sensor 102 to be flexible and conform to the surface and contours of the element to which it is attached.

[0070] The piezoelectric material sensor 102 also has the advantage of having a lower electrical consumption than a resistive gauge.

[0071] The cable 120 fastening system in the opening 130 of the housing 114 could be applied to devices other than the device 100 described above. Thus, this fastening system can be applied to any type of mechanical part to which a cable is intended to be mechanically fastened by a fastening screw disposed in a hole, for example a tapped hole, formed in the mechanical part. The hole comprises an open end leading into an opening through a wall of the mechanical part and into which the cable is intended to be inserted. The axis of the hole is perpendicular to the axis of the opening. A threaded portion of the fastening screw is intended to be screwed laterally into a sheath of the cable at an intersection between a volume of the hole and a volume of the opening.

[0072] Various embodiments and variations have been described. A person skilled in the art will understand that certain features of these various embodiments and variations could be combined, and other variations will become apparent to a person skilled in the art.

[0073] Finally, the practical implementation of the embodiments and variants described is within the reach of a person skilled in the art, based on the functional indications given above.

Claims

Demands

1. A strain measurement device (100), comprising at least: - a strain sensor (102) comprising at least one portion of piezoelectric material having a thickness of less than 50 pm and which is attached to a first part (104) of a flexible support (106); - a housing (114) to which a second part (108) of the flexible support (106) is mechanically attached; - a connecting cable (120) comprising a first end electrically coupled to a connector (122) and a second end (124) mechanically attached to the housing (114); and wherein the second end (124) of the connecting cable (120) is electrically coupled to the strain sensor (102) by at least one connection disposed in the housing (114).

2. Strain measurement device (100) according to claim 1, further comprising at least one electronic measurement acquisition circuit (112) configured to receive and process a measurement signal intended to be delivered by the strain sensor (102), disposed in the housing (114) and electrically coupled to the strain sensor (102) and to the second end (124) of the connecting cable (120).

3. Strain measuring device (100) according to claim 2, wherein the electronic circuit (112) is secured to the second part (108) of the flexible support (106).

4. A strain measuring device (100) according to any one of the preceding claims, wherein the second part (108) of the flexible support (106) is mechanically attached to the housing (114) and comprising at least one resin (118) covering the second part (108) of the flexible support (106) and hermetically sealing the housing (114) by filling at least one cavity (116) of the housing (114) in which at least the second part (108) of the flexible support (106) is disposed.

5. A strain measuring device (100) according to any one of the preceding claims, wherein said at least one connection comprises at least one weld between at least one wire conductor (121) of the connecting cable (120) and at least one connecting pad arranged on the second part (108) of the flexible support (106).

6. Strain measuring device (100) according to any one of the preceding claims, wherein the housing (114) is rigid and metallic.

7. Strain measuring device (100) according to claim 6, wherein the connecting cable (120) has a shielding braid (123) disposed between at least one conductor wire (121) and a sheath (125) of the connecting cable (120) and electrically coupled to the housing (114).

8. A strain measuring device (100) according to any one of the preceding claims, wherein the second end (124) of the connecting cable (120) is mechanically secured to the housing (114) by at least one fixing screw (126) disposed in a hole (128) formed in the housing (114), the hole (128) comprising an open side leading into an opening (130) through a wall of the housing (114) and into which the second end (124) of the connecting cable (120) is inserted, an axis of the hole (128) being perpendicular to an axis of the opening (130), at least one threaded portion of the fixing screw (126) being screwed laterally into a sheath (125) of the connecting cable (120) at an intersection between a volume of the hole (128) and a volume of the opening (130).

9. Strain measuring device (100) according to claims 7 and 8, wherein the fixing screw (126) is electrically conductive and ensures electrical contact between the shielding braid (123) and the housing (114).

10. A strain measuring device (100) according to any one of the preceding claims, wherein the flexible support (106) forms a ribbon extending from its first part (104) to its second part (108).

11. Strain measuring device (100) according to any one of the preceding claims, wherein the portion of piezoelectric material comprises a piezoceramic material.

12. Method for making a deformation measuring device (100), comprising at least: - fabrication of a strain sensor (102) comprising at least one portion of piezoelectric material whose thickness is less than 50 pm and which is attached to a first part (104) of a flexible support (106); - mechanical attachment of a second end (124) of a connecting cable (120) to a housing (114); - mechanical attachment of a second part (108) of the flexible support (106) to the housing (114); - fabrication of at least one connection between the second end (124) of the connecting cable (120) and the strain sensor (102) in the housing (114), the connecting cable (120) also comprising a first end to which a connector (122) is electrically coupled.

13. A method of embodiment according to claim 12, wherein the mechanical bonding of the second part (108) of the flexible support (106) to the housing (114) comprises a dispensing of at least one resin (118) in at least one cavity (116) of the housing (114) in which at least the second part (108) of the flexible support (106) is disposed, hermetically sealing the housing (114).

14. A method of embodiment according to any one of claims 12 or 13, wherein the mechanical attachment of the second end (124) of the connecting cable (120) to the housing (114) comprises screwing at least one fixing screw (126) into a hole (128) formed in the housing (114) and comprising an open side leading into an opening (130) through a wall of the housing (114) and into which the second end (124) of the connecting cable (120) is inserted, an axis of the hole (128) being perpendicular to an axis of the opening (130), such that at least one threaded portion of the fixing screw (126) is screwed into a sheath (125) of the connecting cable (120) at an intersection between a volume of the hole (128) and a volume of the opening (130).