EP1098233A1 - Metallic case element with protusions made of synthetic material - Google Patents

Abstract

The watch casing (9) has a trim of sets of synthetic bosses (23) joined by strips (20) and inserted in a groove and matching slots in the edge (11) of the metal case.

Description

The present invention relates to a metal box element obtained by a process making it possible to have, on all or part of its surface, discontinuous raised areas made of synthetic material, i.e. a bi-material metal / synthetic material object.

Subsequently we will refer by way of example to a watch case, and more particularly to a new design of a rotating bezel adapted to such a watch.

In the construction of watch cases there is always a choice difficult in terms of the materials to be used. Metal, even a metal noble such as gold, used alone gives the finished product solidity and guaranteed quality, but has the disadvantage of weighing down the finished product, being ill-suited to the machining of complex shapes and having the "cold" appearance of metal. The synthetic materials used alone have the advantage that they can be molded or injected with very complex shapes and varied and attractive colors, but cause the consumer to fear not finding in such products the qualities he could claim with the products metal front legs. Some box constructions are however bi-material, in particular to lower the cost of the product. As example the document CH 79 203 describes a noble metal box of very thin, which has an obviously reinforced all-around by an invisible plastic lining. Other constructions also using both metal and plastic to technical reasons can be cited.

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

In the document CH 575 616, which also relates to a box of watch with rotating bezel, a metal outer ring protects a ring plastic interior to hold the bezel in the middle and leave visible on the outside a plastic ring able to create or support various decorative elements.

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

The present invention aims instead to provide a bi-material construction in which the angular sectors of the visible parts of the box or specific areas of said sectors, alternate metal / synthetic material giving the product a less aesthetic appearance cold than metal and / or can provide a technical advantage such as better grip of the object concerned.

To this end, the invention relates to a metal box element having a wall whose outer surface has disjointed bosses formed by a synthetic material, characterized in that a face opposite the outer surface of the element comprises a groove connected to said surface exterior by through passages at locations provided for the bosses and in that said bosses come from a lining in one synthetic material projecting from the exterior surface, being bonded between them through said through passages to a bead, also in a synthetic material, held at the bottom of the groove.

In the case of a watch case, the "elements" to which the invention may apply are obviously the middle and the bezel, that this last either fixed or mobile.

The visible bosses on the wall can, according to the invention, have various aesthetic aspects, as to the form and as to their coloring. The shape depends on the section of the through passages and the coloring varieties of synthetic materials used. In the embodiment the simpler we can use a single synthetic material to form, by known molding or injection processes, the bead and the bosses. he it is also possible to obtain bosses of different colors by performing a sequential forming of the synthetic material, that is to say in using synthetic materials having the same basic composition or compositions capable of binding together, but incorporating pigments different. Similarly it is possible to use synthetic materials different for the bosses and for the cord so as to have a touch soft for bosses and good mechanical resistance for the bead.

So that the bosses, once in place, resist pressure outside, 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 allowing axial immobilization. According to another embodiment, when the cord is made of a material easily deformable synthetic, the groove may include a pinch allowing the strength of the cord. It is also possible that the open groove of the throat 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 edge upper part of the middle if the bosses in synthetic material are provided in the bezel. The "added piece" will be for example the socket circle if said bosses are formed in the middle part. In case the groove is located near the open base of a wall, said groove can, at crossing right 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 characteristics of the invention will appear more clearly on reading the following description of a chronograph watch with a rotating bezel, made with reference to the appended drawings in which:

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

The chronograph watch shown in top view in Figure 1 comprises in a known manner a housing inside which is placed a chronograph movement (not shown), and the middle 1 has a time setting crown 2 and two pushers 3 for start / stop and reset functions, or even timing a time intermediate for the movements provided for this purpose. Dial 4, shaped circular, includes an analog display, for the current time by the hour / minute hands 5 and small seconds 6, and for timing by a second in the center 7 and two counters 8. This watch chronograph also includes a rotating bezel 9, very often useful in this type of timepiece to do a retrograde count of the time, for example to give safety indications on a time of diving.

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

With particular reference to Figures 3 and 5, it can be seen that the annular profile 10 includes an outer surface 11 inclined towards the outside up to an edge 11a, a base 12, and an internal wall 14 formed of a broken surface, a vertical portion 14a of which includes a groove circular 16 intended to subject by known means not shown, the rotating bezel 9 in the middle 1. The base 12 comprises on all its periphery of a groove 15 having for section a rectangular trapezium whose sides are respectively parallel to the outer surface 11, to the base 12 and to the vertical portion 14a of the internal wall 14. The base 12 has also two small annular extensions 17, 18 whose radial spacing is greater than the opening of the groove 15 and the outer edges of which 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 in FIG. 3 and on the sectional representation of Figure 7 the base 12 also has two diametrically opposite zones 19 and reinforced by two small tubes metal 19a inside which will engage the fins of a ratchet spring 19b.

The edge of the profile 10 finally comprises six zones 13 regularly distributed and comprising notches 13a, 13b, 13c whose bottom goes to the less to the groove 15. In the example shown in Figure 3, each zone 13 has five notches.

A central notch 13c, exactly positioned between two marks successive dividing the hour turn from 10 minutes into 10 minutes will allow after placement of the synthetic lining 20 to have a marking of 5 minutes in 5 minutes. Two notches 13b and 13a, deep decreasing are provided on either side of this central notch 13c.

The annular profile 10 which has just been described is that which corresponds to the simplest and most easily automated machining. It is quite 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 middle 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 FIG. 4, it can be seen that the lining 20 in synthetic material actually consists of two half sectors 21a, 21b which are not contiguous and have a small angular offset of the order of 6 ° on either side of the reinforced zones 19 for the ratchet spring 19b.

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

The bosses 23a, 23b, 23c are of course connected by small portions 25a of cord 25 and have different adapted lengths to the length of the notches 13a, 13b, 13c. As seen on sectional representations of FIGS. 6A to 6C, each boss comprises a vertical part 24, an oblique part 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 rounding. We will observe that the spout 29 allows the lining 20 to be immobilized axially. According to a variant of realization this axial immobilization can be obtained by pinching the bead 25 inside the groove 15 whose walls would for example slightly inclined so that the width of the groove 15 is a little less at the width of the cord 25. The different boss lengths are obtained by simply varying the length of the inclined surface 26a, 26b or 26c of each boss. Finally, we will observe, in particular on the Figures 6B and 6C, that the base of each boss and their oriented part against the telescope take into account the necessary technical characteristics when assembling the bezel on the middle. To this end, 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 allowing to have a plurality of imprints.

This configuration of the lining 20 in two parts 21a, 21b, made necessary by the presence of the two zones 19 with ratchets, has the advantage to make assembly easier on profile 10 by sliding the bosses 23a, 23b, 23c of each part 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 produce the lining 20 in having a soft touch synthetic material for bosses and a other material with greater mechanical strength for cord. In such an embodiment it is then possible to carry out the cord in one piece, either by keeping the small ratchet tubes 19a which will then be partially driven out in this second material, either by eliminating and providing a rack structure at the base of the cord.

The bezel which has just been described then has bosses made entirely of synthetic material, firmly bonded together and capable of withstand numerous manipulations without damage, the result is not possible to get with a simple product application synthetic on preformed metal bosses. Without going beyond the scope of the invention, the skilled person can apply the same technique to other part of a box, or even any metallic object, even if it does not correspond to the usual definition of a box.

Claims (9)

Metal box element (9) having a wall whose surface outer (11) has separate bosses (23a, 23b, 23c) formed by a synthetic material, characterized in that a face (12) facing the outer surface (11) of the element (9) comprises a groove (15) connected to said outer surface (11) through through passages (13a, 13b, 13c) at locations provided for the bosses (23a, 23b, 23c) and in that said bosses (23a, 23b, 23c) come from a lining (20) in one synthetic material projecting from the outer surface (11), being bonded between them through said through passages (13a, 13b, 13c) at a cord (25), also made of synthetic material, held at the bottom of the groove (15). Box element according to claim 1 corresponding to the bezel (9) of a watch case with circular dial (4), characterized in that the through passages are formed by notches (13a, 13b, 13c), made in an edge (11a) of the telescope to join the groove (15), through which the bosses (23a, 23b, 23c) protrude. Box element according to claims 1 or 2 characterized in that the bosses (23a, 23b, 23c) are grouped into zones (23) evenly distributed over the surface (11). Box element according to claims 2 and 3, characterized in that the bosses of each zone (13) are symmetrical with respect to a median boss (23c). Box element according to claims 3 or 4, characterized in that the bosses (23a, 23b, 23c) of the same area (23) have different configurations. Box element according to claim 1, characterized in that the bosses (23a, 23b, 23c) form a beak (29) extending over the surface (11) beyond the through passages to axially immobilize the trim (20). Box element according to claim 2, characterized in that the gasket (20) is formed by two half sectors (21a, 21b) corresponding each with an arc less than 180 °. Box element according to claim 1, characterized in that the same synthetic material is used to form the entire lining (20) comprising the cord (25) and the bosses (23a, 23b, 23c). Box element according to claim 1, characterized in that all or part of the bosses (23a, 23b, 23c) are made of materials different synthetics or in the same material incorporating different pigments.

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