Support for e.g. temperature sensor of e.g. wristwatch, has integrated electric connection tracks, first rigid connection interface toward sensor, and second flexible connection interface formed by wire springs assembled to support

[0001] la there is a holder for a sensor to be mounted in a watch electromechanical. for a watch bracelet provided with sensor modules, of sensors such as temperature or pressure, it is necessary to ensure, on the one hand, a robust attachment of the sensor relative to the housing, and providing, on the other hand, electrical connection interfaces to a control IC.

[0003] for this purpose, when the geometric shape allows the sensors, they may be arranged in housings of corresponding shape formed in the middle part; otherwise they are generally attached to a sidewall of the middle through an intermediate piece mounting and a fastener. The sensor module further includes generally a printed circuit board (PCBs), upon which are formed electrical connection tracks by galvanic deposition. The plate contains electrical connectors for the sensor, to which it is physically attached, and manages the electrical connections to the integrated circuit main control, which is disposed elsewhere within the housing, most often on another PCBs, especially via a zebra connector.

[0004] en due to the different parts required for the installation and connection of the different interfaces, assembling such sensor modules is relatively complex and expensive.

[0005] il therefore there is a need for sensor modules free of these limitations.

[0006] en particular, an object of the present invention is to provide a holder for a sensor clockwork which allows easier mounting and involves a number of parts and interfaces more restricted.

[0007] these aims are achieved by a holder for a sensor of a timepiece, characterized in that it is designed 3D/PWM with tracks integrated electrical connection.

[0008] un advantage of the proposed solution is that it incorporate into a single component mechanical and electronic functionalities for mounting the sensor in the housing clockwise and its interconnection with a control IC, which significantly simplifies the assembly process and reducing congestion in the housing.

[0009] un further advantage of solution of the present invention is that it eliminates the need to PCB pattern, rigid or flexible, and zebra connectors typically used in watchmaking, at the sensor holder, thereby of suppressing sockets and minimize the ohmic resistance of the module. Thus the Joule losses are also reduced.

[0010] yet another advantage of the solution of the present invention is that it provides a greater flexibility for assembly within a watch casing, the sensor module can now be mounted on the dial side and bottom side while a solution using zebra connectors cannot be mounted from the side face of a clock. Further, the sensor module can be assembled integrally autonomously and thus more easily delocalized in the housing, or positioned at different locations in separate cases.

[0011] according to a preferred embodiment, the sensor support of a timepiece according to the invention comprises a first rigid connection interface to the sensor, and a second flexible connection interface for connection to a control IC. This solution has the advantage of requiring a lower precision for positioning the module in the box, the flexible connectors capable of retrieving the operating play important, unlike a PCB.

[0012] d'other characteristics and advantages of the invention more clearly [...] the detailed description and drawings, in which:

the fig.. 1a shows a view of a first face of a sensor holder for timepiece according to a first preferred embodiment, which is arranged on a housing for the sensor and interface with the sensor;

the fig.. 1b shows the sensor holder of the fig.. 1a, with the sensor assembled in its housing;

the fig.. 2a shows a view of the opposite side of the sensor holder according to the preferred embodiment illustrated in fig.. 1a, on which is arranged the connection interface to an external integrated circuit;

the fig.. 2b shows a view of the face of the sensor holder according to the preferred embodiment as illustrated in the Figure. 2a, evidencing the shape and positioning of spring wires;

the fig.. 2c shows the sensor holder according to the preferred embodiment illustrated in fig.. 2b, with all springs and wires assembled mounting feet inserted into side notches;

figure 3 represents a sensor holder for timepiece according to a second embodiment [...] -

[...], including flexible fingers on which are arranged tracks of electrical connections

structured laser.

[0013] la 3D/PWM, which is an acronym for "conveying Interconnect Device-[...]" in three dimensions, includes fabricating a plastic part injected containing connecting tracks embedded therein, formed in particular by developing a technique called laser structuring [...] - acronym for "direct laser [...]". In a first step, the geometric shape of the part is determined by the form of a mold, comprises injecting a first non-conductive material but specifically optimized for the [...] method. And then laser patterning surfaces that will become the connecting tracks on the injected part. Finally the shaped workpiece undergoes a chemical plating treatment, during which only the surfaces previously laser exposed will be able to hang the metalization. This technique allows increased flexibility for the design of parts for integration in apparatuses of given shape, as e.g. antennas for mobile telephones, for which the constraints are increasingly pointed in terms of volume. It also enables an optimization of the production process of electronic components with better yields for mass production. Alternatively to the [...] technology described above, the PWM/3D parts may also be produced by other methods, and in particular by a bi-material injection technique, also called "injection molding two component". This method uses two plastic materials, one of which may be metalized to create the electrical interconnection tracks, while another material remains passive. This two-component method (2c) needs investment higher than the technique [...], but still possible reduction in costs per piece for large volumes of production. Other techniques are also conceivable, such as for example a direct bonding to silver by aerosol spray, followed by a sintering process.

[0014] l'use of a sensor holder fabricated in an 3D/PWM in the context of the invention for a timepiece will help the need for a dedicated sensor support, resulting in a space saving and simplification of assembly, and a connector zebra usually used for the connection to the driver IC, thereby minimizing the sockets and offers more flexibility for the positioning of the sensor module in the housing.

[0015] the Figure. 1a and 1b and 2a and 2c show a sensor holder 1 according to a first preferred embodiment of the invention, and fig. 3 shows a sensor holder 1 according to a second preferred embodiment of the invention.

[0016] according to each of the two preferred embodiments, the support 1 comprises a first rigid connection interface to the sensor 2, and a second connection interface flexible toward an integrated circuit, in order to allow recovery of the running clearances often critical in the manufacturing timepieces and thus ensuring contact with the driver IC.

[0017] in Figure. 1a, the sensor holder 1 is shown when viewed from the side of a first face 11 on which is arranged the connection interface with the sensor 2, for which a housing 21 is provided at the center. At the housing 21, and first through holes 16 are provided for forming fixing clips 18 on the opposite side in molding the sensor holder 1, visible on the Figure. 2a and 2c following, whereas second through holes 17 are arranged below to provide double security of attachment and connection, as is explained further on the basis of the same Figure. 2A AND 2C. On one end of the electrical connection tracks 10, which are herein preferably patterned laser, there are connectors 102 squares arranged at the periphery of the housing 21 for connecting the sensor 2, while on the upper edge of the support 1 there are enlarged portions of electrical connecting tracks 101 10 arranged in clearances 15 arranged symmetrically about a central projection 150. These enlarged portions are directed to facilitate the implementation of tests electrical carriers and facilitating proper interconnection of tracks across the structuring process tracks by laser, while the arrangement of these enlarged tracks 101 in clearances 15 at an edge of the support aims to protect them from accidental damage, preferably by grinding, during transportation and/or handling of the carrier 1. thus requiring a technique for conveying bulk carriers 1 optimizing efficiencies without risking infringing on the electrical conduction properties of the support 1.

[0018] on the left side of the support is arranged a first locator the laser 110 for proper location during the laser structuring tracks. Has left the cavity 21 is a round which serves to periodic visual for the correct assembly of the carrier. This second polarizing key mounting 19 here has the form of a hollow. In the middle and on either side of the first face 11 of the support 1 there are fastening elements 14 for mounting the holder 1 on the watch case; according to the first preferred embodiment describes those fasteners 14 to the housing takes the form of indentations 140 which are adapted to cooperate with the mounting feet 4 described below and visible on the Figure. 2B AND 2C.

[0019] la Figure. 1b shows the sensor carrier shown in fig. 1. 1a, i.e. when viewed from the side of the first face 11, which is now mounted on the sensor 2 in its central portion. All references of fig. 1 b., except the sensor 2, are already illustrated in Figure. 1a (fastening elements 14 in the form of indentations 140, second through holes 17, connection tracks 10 and enlarged portions 101, clearances 15 and central projection 150) and have already been described.

[0020] the Figure. 2a to 2c show the sensor holder 1 seen from a second side 12, which is the face opposite the first face 11 shown in the Figure. 1a and 1b. In Figure. 2a, on which there are always the first locator the laser 110, electrical connection tracks 10 structured laser as well as clearances 15 and the central projection 150, it may be seen that the notches 140 are provided with fixing, on the other side, a shoulder 141 which has a hand a bearing surface 1411 for mounting the mounting feet visible in Figure 4. 2c and a locking surface rotationally 1412, [...] to say the vertical walls and straight which eliminate any fastener received in the notch 140 and on the shoulder to rotate, for example during a screwing operation.

[0021] in Figure. 2a, distinguished further, the center of the sensor 1, and recesses are provided for receiving springs 3 wires, one of which is visible in Figure. 2b and all, in the mounted position, in Figure. 2C. Each of these grooves is bordered by a series of clips 18, for assembling the spring wire support 3 1 sensor. The springs wire 3 are first sandwiched between two clips 18 adjacent bordering [...], thereafter they are forced inwardly, the clips 18 plated for then holding them in their housings. At each of the 4 second through holes 17 are arranged eyelets 103 connection to be electrically connected to each of the springs 3 wires.

[0022] la Figure. 2b illustrates the same second side 12 of the sensor carrier shown in fig. 1. 2a, in mounting a spring wire 3 inside a second through hole 17. All references are identical to those already been described based on the Figure. 2a, except the spring wire 3 form the interface provided for flexible connection to a driver IC positioned elsewhere within the housing. The spring wire 3 has a particular shape bent, at almost 180 degrees, 31 being a first portion for attachment to the sensor holder 1 by being confined in the recesses and retained not clips 18, while a second portion 32, the end of which is free and flexible, is that which will be connected to the driver IC and will be able to recover running clearances. Schematically, the first portion 31 of the spring wire constitutes the part can disconnect the sensor holder constructed 3d PWM/1, while the second part 32 of the spring wire 3 is that which constitutes the connecting portion to the integrated circuit. Although other geometric shapes are possible, the particular form hairpin according to the preferred embodiment illustrated provides a maximum contact surface at each of the connection interfaces, [...] to say to the integrated circuit and to the sensor, while exhibiting sufficient strength at the joint between each of the connecting parts to recover running clearances if necessary, and parallel to exert a bias force of sufficient magnitude to press the second portion 32 in contact to a contact piece with the integrated circuit when the first and second parts 31.32 are moved towards each other.

[0023] to further improve both fixing the springs support wires 3 1 sensor and also provide redundancy of electrical contacts, for example of cases of violent shock tending to move slightly the first portion 31 of the springs 3 wires attached to the support, there is provided, according to the preferred embodiment described, welding the lower end of the spring wire 3, bent 90 degrees to here down the first portion 31 attached to the support 1 and which is brought into contact with the eyelets 103 connecting, at the upper end of the second through holes 17. Alternatively, the end of the spring wire 3 could also be glued into the second through hole 17 by means of an electrically conductive adhesive, such as silicone-based conductive adhesives, thixotropic properties, which are unlikely to be cast, including during the polymerization process, unlike a conventional alloy of tin used for welding and which liquefies completely during this operation, so that it is more difficult to control quality and long term reliability of the welded area. An additional benefit of a conductive adhesive silicone is its mechanical compliance, that can make the assembly more robust mechanical stresses, shock or vibration, instead of solder which remains very rigid and may for example cracking upon mechanical stresses. Finally the use of a conductive adhesive has the advantage of curing at temperatures lower than the melting point of tin (clade. 130 °c against 250 °c), so that the risk of damage to the plastic of the shaped support part is, unlike during a welding operation.

[0024] on can also imagine, in a subsequent use of the sensor holder 1 according to the invention, replace the springs wires 3 by versions that would have a portion 32 longer or shorter, so as to be more flexible with regard to the connection position by PCB.

[0025] in Figure. 2c, we can see all springs wire 3 in the assembled position the support 1 sensor 2, as well as fixing legs 4, which comprise a truncated cylindrical flange 41 which fits on the shoulder of the notch 141 140 once the part cylindrical legs Y have been engaged and clipped by the outside. The flange 41 comprises truncated cylindrical, as the shoulder of the notch 141 140 attachment, an axial abutment surface 141 which may be held in contact against the axial stop surface 1411 of the shoulder, and a locking surface rotationally 412, which is formed by the straight vertical wall of the truncated portion of the flange 41. The fastening foot 4 left is shown in an assembled position to the carrier, while the fastening foot 4 right is shown when in the notch clip fastening. This attachment structure with legs 4 and indentations 140 of particular shape advantageously allows fastening the holder 1 sensor for example from outside the housing, screws that can be inserted into the central openings 42 of each foot 4. such an attachment by the exterior of the housing - with a bore in the wall of the housing - is obviously advantageous over one fixing by the interior of the housing, where the lack of space and size is possible by various parts makes any screwing operation troublesome relatively quickly. Further, this mode of assembly with mounting feet 4 thus permits an increased freedom of positioning of the support 1 in the direction perpendicular to the plane of the second side 12, thereby making the entire assembly to the offsets robust mounting of the sensor in the radial direction perpendicular to a wall of the housing. Indeed, there is never of overstress side on the fastening screws and the corresponding seals, thereby sealing the watch in any case.

[0026] Fig. 3 illustrates another preferred embodiment for the sensor 1 according to the invention, wherein the flexible connection interface to the integrated circuit is not formed by springs wires, but by flexible fingers 13 formed integrally with the rest of the 3D sensor/PWM, and upon which is directly arranged connecting tracks 10 electrical, laser or structured e.g. obtained by bi-material injection. In this embodiment, the manufacturing process of the sensor holder is thereby further simplified; however such an manufacture has drawbacks, in the long run, in terms of connection quality because the bond fingers 13 are susceptible to wear at the joint with the body of the sensor, the electrical connection tracks 10 that can be damaged at that level, or even interrupted. Another difference between this second preferred embodiment and that shown in Figures preceding concerns the manner of fixing the housing, since it is appreciated that the support is not provided with indentations 140 side but through holes 140', whose cylindrical shape allows the introduction of a screw head by therein for securement to the housing. As discussed previously, the variant in the attachment has the drawback of being more delicate, but however the advantage of requiring a piece less and therefore saving unit cost, mis-an improvement of production efficiency. As for the embodiment shown in the Figure. 1a-b and 2a-C., the prevalence of noted that the widened sections 101 10 electrical connection tracks of their arrangement in clearances 15 symmetrically arranged around a central projection 150 have been preserved to facilitate an electrical test and protect the tracks during treatment in the optional bulk carriers 1.