EP1098233B1 - Metallic case element with protusions made of synthetic material - Google Patents

Abstract

The element (9) has a wall whose outer surface (11) comprises disjointed knobs (23a-23c) formed by synthetic material. A face of the element opposite to the outer surface of the wall has a groove connected to the outer surface by through passages at locations provided for the knobs. The knobs originate from a synthetic material filler (20) projecting from the outer surface. The knobs are connected to each other and to a synthetic material strand via the passages. The strand is held on bottom of the groove. The knobs are regrouped in zones regularly distributed over the outer surface.

Description

The present invention relates to a metal box element obtained by a method for having, on all or part of its surface, discontinuous zones in relief made of a synthetic material, that is to say a bi-material metal object. / synthetic material.

Thereafter reference will be made by way of example to a watch case, and more particularly to a new design of rotating bezel adapted to such a watch.

In the construction of watch cases there is always a difficult choice in terms of the materials to be used. The metal, even a noble metal such as gold, used alone gives the finished product solidity and quality guarantee, but has the disadvantage of weighing down the finished product, of not being able to lend itself to the machining of complex shapes and to have the "cold" appearance of the metal. Synthetic materials used alone have the advantage of being molded or injected with very complex shapes and varied and attractive colors, but cause the consumer the fear of not finding in such products the qualities that he could claim with them. previous products completely made of metal. Some box constructions are however bi-material, especially to lower the cost of the product. For example, the document CH 79 203 describes a noble metal box of very small thickness which comprises all around its periphery an evident reinforced by a non-apparent lining of plastic material. Other constructions that also use both metal and plastic for technical reasons can be cited.

In the document EP 0 370 947 describing a rotating bezel watch, said metal bezel is provided with a plastic toothed ring fixed notch between the middle and an annular housing of the rotating bezel to cooperate with at least one pawl; the ring of synthetic material is not visible and the watch has a completely metallic appearance.

In the document CH 575 616 , which also relates to a rotating bezel watch case, a metal outer ring protects a plastic inner ring intended to retain the bezel in the middle and to leave a ring of plastic material visible to the outside, capable of creating or support various decorative elements.

The document US 5,631,880 also relates to a rotating ring watch case having a first rigid ring rotatably mounted on the bezel for supporting decorative elements and a second elastic ring for facilitating rotation and protection against shock of the first ring.

As seen in the examples above, the plastic used in combination with the metal always has a continuous annular shape, either fully visible or completely hidden.

As seen in the examples above, the plastic used in combination with the metal always has a continuous annular shape, either fully visible or completely hidden.

The present invention aims on the contrary to provide a bi-material construction in which the angular sectors of the visible parts of the box or of the determined zones of said sectors, have an alternation of metal / synthetic material giving the product an aesthetic appearance less cold than the metal and / or may provide a technical advantage such as better grip of the object concerned.

To this end, the subject of the invention is a metal box element having a wall whose outer surface comprises disjointed bosses formed by a synthetic material, characterized in that a face facing the outer surface of the element comprises a groove connected to said outer surface by through-passages at locations provided for the bosses and in that said bosses originate from a lining of a synthetic material projecting from the outer surface, being interconnected through said passages through a bead, also of a synthetic material, held at the bottom of the groove.

In the case of a watch case, the "elements" to which the invention can be applied are obviously the middle and the bezel, the latter is fixed or mobile.

The bosses apparent on the wall may, according to the invention, have various aesthetic aspects, as to the shape and color. The shape depends on the section of the through passages and the coloring of the varieties of synthetic materials used. In the simplest embodiment, a single synthetic material can be used to form, by known molding or injection methods, the cord and the bosses. It is also possible to obtain bosses of different colors by performing a sequential forming of the synthetic material, that is to say by using synthetic materials having the same base composition or compositions that can bind to each other, but incorporating different pigments. Similarly it is possible to use different synthetic materials for the bosses and for the cord so as to have a soft touch for the bosses and good mechanical resistance for the cord.

So that the bosses, once set up, withstand external pressure, it is necessary that the cord to which they are connected is firmly held in the groove. According to a first embodiment each boss may extend on the outer surface slightly beyond the through passage to form a spout for axial immobilization. According to another embodiment, when the bead is made of an easily deformable synthetic material, the groove may comprise a nip allowing the cord to be forced into force. It is also possible that the open groove of the groove is closed by another element of the box or by an insert therein, such as a rigid ring. In the case of a wristwatch "the other element of the box" will be for example the upper edge of the middle part if the bosses of synthetic material are formed in the bezel. The "insert" will for example be the casing circle if said bosses are formed in the middle part. In the case where the groove is located near the open base of a wall, said groove may, in the right of through passages be open in the base to communicate with the outer surface of the wall.

• la figure 1 est une vue de dessus d'une montre chronographe à lunette tournante bi-matière,
• la figure 2 est une vue de dessus de la lunette seule avant montage sur la carrure,
• les figures 3 et 4 représentent, en vue de dessous respectivement la partie en métal et la partie en matériau synthétique de la lunette,
• la figure 5 est une coupe agrandie selon la ligne V-V de la figure 2,
• les figures 6A, 6B, 6C sont des représentations agrandies en coupe selon les lignes A-A, B-B et C-C de la figure 2, et
• la figure 7 est une coupe agrandie selon la ligne VII-VII de la figure 3.

Other advantages and features of the invention will appear more clearly on reading the following description of a rotating bezel chronograph watch, made with reference to the appended drawings in which:

• the figure 1 is a top view of a bi-material rotating bezel chronograph watch,
• the figure 2 is a top view of the bezel alone before mounting on the middle part,
• the Figures 3 and 4 represent, in bottom view respectively the metal part and the synthetic material part of the bezel,
• the figure 5 is an enlarged section along line VV of the figure 2 ,
• the Figures 6A, 6B, 6C are enlarged representations in section along the lines AA, BB and CC of the figure 2 , and
• the figure 7 is an enlarged section along line VII-VII of the figure 3 .

The chronograph watch represented in top view at the figure 1 comprises in a known manner a housing inside which is placed a chronograph movement (not shown), and whose middle part 1 comprises a time-setting ring 2 and two push-buttons 3 for start / stop functions and delivery to zero or even timing of an intermediate time for the movements provided for this purpose. The dial 4, of circular shape, comprises an analog display, for the current hour by the hour / minute hands 5 and the small second 6, and for the timing by a second in the center 7 and two counters 8. This watch Chronograph further comprises a rotating bezel 9, very often useful in this type of timepiece to make a retrograde count of time, for example to give safety indications on a dive time.

This rotating bezel 9, shown separately at the figure 2 , is an illustrative example of a bi-material construction according to the invention. It comprises an annular profile 10 of metal, viewed from below to figure 3 , and a trim 20 of synthetic material shown in FIG. figure 4 . The lining 20 forms on the surface 11 of the profile 10 six zones 23 regularly distributed and composed of boss 23a, 23b, 23c, these bosses not being represented on the figure 2 at the 9 o'clock position. for a better understanding of the shape of the profile 10. Between each zone 23 of bosses, the surface comprises markings 22 for splitting the hour turn of 10 minutes in 10 minutes.

With particular reference to figures 3 and 5 it can be seen that the annular profile 10 comprises an outer surface 11 inclined outwards to an edge 11a, a base 12, and an inner wall 14 formed of a broken surface of which a vertical portion 14a comprises a circular groove 16 intended to secure by means known not shown, the rotating bezel 9 to the middle 1. The base 12 comprises all around its perimeter groove 15 having a rectangular trapezoidal section whose sides are respectively parallel to the outer surface 11, the 12 and the vertical portion 14a of the inner wall 14. The base 12 also has two small annular extensions 17, 18 whose radial spacing is greater than the opening of the groove 15 and whose outer edges are guided by the walls of an annular rotation path 31 formed in the upper edge of the middle part 1. As can be seen on the figure 3 and on the sectional representation of the figure 7 the base 12 also has two zones 19 diametrically opposed and reinforced by two small metal tubes 19a within which will engage the vanes of a ratchet spring 19b.

The edge of the profile 10 finally comprises six zones 13 regularly distributed and having notches 13a, 13b, 13c whose bottom goes at least to the groove 15. In the example shown in FIG. figure 3 each zone 13 comprises five notches.

A central notch 13c, exactly positioned between two successive marks dividing the 10-minute time lapse in 10 minutes will allow after placement of the synthetic liner 20 to have a registration of 5 minutes in 5 minutes. Two notches 13b and 13a, decreasing depths are formed on either side of this central notch 13c.

The annular profile 10 which has just been described is that which corresponds to the simplest machining and the most easily automated. It is obvious that, equivalently, the notches 13a and 13b could have, as the central notch 13c a radial orientation, and / or the same depth as said central notch 13c. Similarly the notches 13a, 13b, 13c could be replaced by through passages joining the surface 11 and the groove 15, without extending to the edge 11a of the profile 10.

Referring now to the figure 4 it can be seen that the lining 20 made of synthetic material consists in fact of two half-sectors 21a, 21b which are not contiguous and which have a small angular offset of the order of 6 ° on either side of the zones 19 reinforced for the ratchet spring 19b.

Each half sector is formed of a bead 25, of the same section as the groove 15 joining the zones 23 of bosses 23a, 23b, 23c which have the same arrangement as the notches 13a, 13b, 13c. These zones of bosses are distributed over the bead 25 so that, after placement in the profile 10, the six middle bosses 23c have an angular offset of 60 °.

The bosses 23a, 23b, 23c are of course connected by small portions 25a of cord 25 and have different lengths adapted to the length of the notches 13a, 13b, 13c. As can be seen in sectional representations of Figures 6A to 6C each boss comprises a vertical portion 24, an oblique portion 26a, 26b, 26c substantially parallel to the surface 11 of the profile 10 and a return 28 against the surface 11 extending slightly beyond a notch 13a, 13b or 13c to form a beak 29, these different surfaces being connected by roundings. It will be observed that the spout 29 makes it possible to immobilize the lining 20 axially. According to an alternative embodiment, this axial immobilization can be obtained by gripping the bead 25 inside the groove 15, the walls of which for example are slightly inclined so that the width of the groove 15 is a little less than the width of the cord 25. The various lengths of boss are obtained by simply varying the length of the inclined surface 26a, 26b or 26c of each boss. Finally, we will observe, especially on Figures 6B and 6C , that the base of each boss and their oriented part against the telescope take into account the technical characteristics necessary for the assembly of the telescope on the caseband. For this purpose, there is provided a clearance 27 corresponding to the groove 16 of the profile 10.

The lining 20 is for example made of Pebax® by injection into a mold for having a plurality of cavities.

This configuration of the two-part packing 21a, 21b, made necessary by the presence of the two ratchet zones 19, has the advantage of making the assembly easier on the profile 10 by sliding the bosses 23a, 23b, 23c each portion 21a, 21b in the notches 13a, 13b, 13c until the cord portions 25 snap into the groove 15.

As indicated at the beginning, it is possible to make the lining 20 by having a soft-touch synthetic material for the bosses and another material having a greater mechanical strength for the cord. In such an embodiment it is then possible to make the cord in one piece, or by keeping the small tubes 19a with ratchets which will then be partially driven into this second material, either by removing them and providing a rack structure at the base of the cord.

The bezel that has just been described then has bosses made entirely of synthetic material, firmly bonded to one another and capable of withstanding a great deal of handling without damage, a result that can not be obtained with a simple synthetic product application. On preformed metal bosses, within the scope of the invention, one skilled in the art can apply the same technique to other parts of a box.

Claims (9)

1. Metal case part (9) having a wall whose outer surface (11) includes disjointed knobs (23a, 23b, 23c) formed by a synthetic material, characterised in that one face (12) opposite to the outer surface (11) of the part (9) includes a groove (15) connected to said outer surface (11) by through passages (13a, 13b, 13c) at locations provided for the knobs (23a, 23b, 23c) and in that said knobs (23a, 23b, 23c) originate from a filler (20) made of synthetic material projecting from the outer surface (11), while being connected to each other through said through passages (13a, 13b, 13c) to a strand (25), also made of synthetic material, held on the bottom of the groove (15).
2. Case part according to claim 1 corresponding to the bezel (9) of a watch case with a circular dial (4), characterised in that the through passages are formed by notches (13a, 13b, 13c), made in an edge (11 a) of the bezel to join the groove (15) through which the knobs (23a, 23b, 23c) project.
3. Case part according to claim 1 or 2, characterised in that the knobs (23a, 23b, 23c) are regrouped in zones (23) regularly distributed over the surface (11).
4. Case part according to claims 2 and 3, characterised in that the knobs of each zone (13) are symmetrical with respect to a median knob (23c).
5. Case part according to claim 3 or 4, characterised in that the knobs (23a, 23b, 23c) of a same zone (23) have different configurations.
6. Case part according to claim 1, characterised in that the knobs (23a, 23b, 23c) form a tip (29) extending over the surface (11) beyond the through passages to immobilise the filler (20) axially.
7. Case part according to claim 2, characterised in that the filler (20) is formed of two half sectors (21 a, 21 b) each corresponding to an arc less than 180°.
8. Case part according to claim 1, characterised in that the same synthetic material is used to form the totality of the filler (20) including the strand (25) and the knobs (23a, 23b, 23c).
9. Case part according to claim 1, characterised in that all or part of the knobs (23a, 23b, 23c) are made of different synthetic materials or a same material incorporating different pigments.

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