EP1065576A1 - Chronograph watch made of precious metal and with a hollow bezel middle - Google Patents

Abstract

Watch casing has guide sockets, for push buttons, with a threaded tube on the outside terminated by a collar. The case is made of at least two disjointed segments (30) defining a central opening for the watch assembly. The casing has threaded holes (35) that align with the push button guide sockets to enable a tight screw fastening of the segments (30) and sealing of the guide sockets. The guide sockets are sealed as a metal annulus of the watch case around is squashed to form a seal.

Description

The present invention relates to a chronograph watch box having a noble metal bezel comprising a recess in which are placed from place to place segments of base material for the purpose functional to allow the assembly of the other constituent parts of said chronograph watch and to ensure watertightness at the winding stem passages.

When a middle or a middle-bezel is made of noble metal, such as gold or platinum it is economically advantageous to have an envelope the thinnest possible, which has the disadvantage of being easily deformable by impact or pressure. Through "envelope", within the meaning of the present invention means a structure rigid enough to be handled, not just a deposit of metal of a few tens of microns on a matrix of base material constituting already the middle or a middle-bezel. Such an "envelope" within the meaning of the present invention is for example obtained in a known manner by the technique electroforming which allows to obtain complex shapes having thicknesses which can vary from a few tens of microns to a few hundreds of microns.

When the thickness of the envelope is too small, for example on the order of 150 to 200 µm, it is necessary to provide means for reinforcement arranged throughout the recess to protect the external wall against shock or pressure.

In document CH-A-79203, such reinforcement is obtained at by means of several segments having the same profile as the internal wall of the middle, said segments being pressed against mounting against said wall at by means of a frustoconical nesting circle. In a more recent document US 5,363,350, four segments covering at least 85% of the periphery of the recess are held in place, either by elastic means arranged in a groove all around or from place to place, either by screwing flanges at the passage of the winding stem. In either case these segments, which are made of metal or vile alloy such as brass, have no virtually no mechanical function other than strengthening and especially contribute to weigh down the timepiece, which has the disadvantage to make believe that it is in noble metal, gold or solid platinum.

In document US 4,995,023 the reinforcement of a 150 μm wall is obtained by stiffening elements coming from material with the wall and locally carrying the thickness of 650 μm, thus conferring on the recess an alveolar structure. Such a structure, also called "honeycomb" is also described in document EP 0 762 240. Such a construction has the disadvantage of unnecessarily consuming noble metal, while giving the timepiece an aspect of lightness which can make one doubt that it is in noble metal.

In document US Pat. No. 4,970,708, it will be observed that the three inserts fixed by gluing or welding in the recess of the arch-shaped middle part no longer have a reinforcement function, but an assembly function consisting in axially positioning the other constituent parts of the watch. It appears however that an assembly by gluing or welding is not not completely satisfactory, especially for timepieces deserving the goldsmith's mark.

We will finally observe that all the timepieces to which it is refers in the aforementioned documents are watches whose middle has only one opening or hole for the passage of the rod winder.

The present invention relates, on the contrary, to a chronograph watch noble metal, that is to say a timepiece comprising not only a stem, but also at least two pushers and whose hollowed-out bezel has sufficient thickness to withstand pressure or impact external, but still insufficient to allow mechanical assembly of all the components necessary for the construction of said watch chronograph. The invention therefore relates in particular to an arrangement allowing to economically produce such an assembly with a reduced number of rooms.

To this end, the invention relates to a chronograph watch in noble metal including a box, closed by a glass and a bottom in support on a rigid bezel having a recess open towards the center of the box and in which are provided through passages for a rod time setting and for guide bushings of at least two pushers, and a chronograph movement with its display device positioned in said box by a casing circle disposed between said movement and said middle-bezel. This chronograph watch is characterized by the fact that the guide bushings include a threaded tube on the outside and finished by a collar and in that at least two disjointed shaped segments substantially like the recess and drilled with a threaded hole are arranged at the straight pusher sockets to allow by screwing from the outside to ensure both a firm positioning of said segments and a sealing at said sockets by crushing a metal ring of the middle-bezel around the passing passages.

These segments held in place by the pusher bushings have also other functional aspects in particular at the level of positioning and fixing the socket circle in which will be introduces from the bottom a preassembled movement also comprising the dial and hands.

One of the segments, in its upper part, on the ice side, is provided with a pin, the head of which protrudes from the face oriented towards the center of the box to cooperate with a notch practiced in the part upper of the nesting circle to allow indexing the position of said nesting circle, that is to say to perfectly align its passages crossing with those provided in the middle and in the segments for the passage of the time-setting rod and the segments respectively. Of so as not to weaken the segment concerned, this pin is preferably placed next to the threaded hole for the plunger socket and not above of it. Equivalently, the pin could be replaced by a tenon coming from material with the segment.

In addition, each segment has, in the lower part of its face oriented towards the center and in an area not located at the level of the threaded hole, a groove parallel to the bottom, into which the screw engages head of an eccentric head screw previously screwed into a housing of the wall of the casing circle which then becomes integral with the segments and the middle-bezel.

As indicated at the beginning, the number of these disjoint segments multifunctional depends on the number of pushers. According to a mode of preferred embodiment, the chronograph watch includes four pushers arranged at 2h, 4h, 8h and 10h and therefore four segments which will occupy 50 to 60% of the recess of the middle-bezel, or even less.

• la figure 1 est une vue de dessus de la montre chronographe;
• la figure 2 est une vue en perspective d'un segment;
• la figure 3 est une vue en coupe au niveau d'un poussoir partiellement démonté, selon la ligne III-III de la figure 1;
• la figure 4 est une vue en coupe au niveau de la goupille d'indexage, selon la ligne IV-IV de la figure 1;
• la figure 5 est une vue en coupe au niveau de la tige de mise à l'heure, selon la ligne V-V de la figure 1, et
• la figure 6 est une vue en coupe au niveau de l'attache de bracelet, selon la ligne VI-VI de la figure 1.

Other characteristics and advantages of the present invention will appear more clearly on reading the detailed description of an embodiment of a chronograph watch with analog display and also comprising two small windows for a digital display, this description being made in reference to the accompanying drawings in which

• Figure 1 is a top view of the chronograph watch;
• Figure 2 is a perspective view of a segment;
• Figure 3 is a sectional view at a partially disassembled pusher, according to line III-III of Figure 1;
• Figure 4 is a sectional view at the level of the indexing pin, along the line IV-IV of Figure 1;
• FIG. 5 is a sectional view at the level of the time-setting rod, along the line VV in FIG. 1, and
• FIG. 6 is a sectional view at the level of the strap fastener, along line VI-VI of FIG. 1.

It is first indicated that the following description is made by describing the parts useful for the invention in the order in which they are used to arrive until the finished product.

With particular reference to Figures 1 and 3, it can be seen that the chronograph watch includes a case 1 with a monobloc middle-bezel 20 of noble metal such as gold is closed by a crystal 12 and a bottom 13. This box is intended to receive a chronograph movement 5 and its display device comprising a dial 6 conventionally having hands 7 and counters 8a, as well as two small windows 8b for a digital display. External control elements comprising four pushers 2, arranged in the positions 2h, 4h, 8h, 10h and a setting rod hour 4.

The middle-bezel 20 has a recess 19 over its entire periphery oriented towards the center of the box 1 and delimited by a wall 18 having in all substantially the same thickness of the order of 400 μm, which gives it already sufficient rigidity to withstand shock and pressure without it it is necessary to provide reinforcement ribs. This bezel 20 is advantageously obtained by the electroforming technique which easily makes it possible to produce hollow deformations in the wall 18 23, 24 respectively intended to partially house the pusher heads 2 (Figure 3) and the crown of the winding stem 4 (Figure 5) and a recessed conformation 28 provided with a through passage 29 for the attachment of a strap (figure 6).

The hollow deformations 23 have a circular opening 25 for the passage of the pusher mechanism 2 comprising a socket 50 to inside which slides a rod 51 extended outside by a head.

As can be seen in FIG. 5, the hollow deformation 24 comprises a circular opening 3, extended by a sleeve 3a coming from material with the wall 18 and having the same thickness as this to allow the guiding the winding stem 4 and sealing at this level.

The upper part of the middle-bezel 20 constitutes the bezel 21 proper and includes a curved edge 22 which ensures sealing at the level of the glass 12 as will be explained later. The lower part comprises at least one ring 17 parallel to the bottom 13 which ensures sealing at this level.

With particular reference to Figures 1 to 4, the following is described how segments 30, arranged in line with the pushers 2, constitute an essential connecting element for mounting the various components of the chronograph watch. In Figure 1 we see that 4 segments 30 are placed in the recess 19, in line with the pushers 2, that they are not joined and that they each occupy an angular sector about 50 °, or approximately 55% of the recess 19, that is to say that they have a very incidental role in the rigidity of the middle or the artificial increase in the weight of the timepiece as a whole. These segments 30 are made of a bright metal, nevertheless having good mechanical properties, such as brass, to allow machining in the substantially median part a threaded through passage 35 provided for coincide with the opening 25 of the middle-bezel 20. The positioning of these segments, which is the first step in assembly, is made easier by a depression 33 formed in the outer face 32 of the segment and shaped to perfectly fit the contour of the hollow deformation 23 of the wall 18 of the middle-bezel 20. This pre-positioning of the segments 30 then makes it possible to engage a casing circle 40 comprising non-threaded through holes 43 and 45, respectively for the passage of the time setting rod 4 and for the pusher mechanisms 2. This circle socket 40 also includes in its lower part (bottom side 13) notches at the bottom of which are drilled 47 for the implementation eccentric head screw position 48.

These eccentric head screws 48 are distributed in the socket circle in the same way as through holes 45, but have an offset angular with respect to these.

The eccentric part of these eccentric screws is designed to come to bear against the bottom of a groove 38 formed in a segment 30 in its face 34 oriented towards the inside of the box 1. For mass production of segments, for example by cutting machined segments from the same brass ring, it is advantageous that the groove 38 extends from one end to the other of the segment. It is also possible that this groove is blind in being machined only at the eccentric head screw 48 with which is cooperates. In its upper part on the glass side, the casing circle 40 has an angular recess 42 which allows said upper part to follow the contour of the internal face of the telescope 21 and of its edge curved 22. By unscrewing, the eccentric head screw 48 will bear on the bottom of the groove 38 and will lock the socket circle 40 against the face internal of the telescope 21. To facilitate the alignment of the openings 3 and 25 in the middle part of the bezel 20, threaded through passages 35 in the segments 30 and holes 43 and 45 in the socket circle, the circle socket includes a notch 41 in which engages a indexing pin 31 inserted in the face 34 of one of the segments 30 in its upper part and substantially above the groove 38. So equivalent the function of pin 31 could be fulfilled by a tenon coming from material with segment 30, in particular in the case where the blank brass is obtained by molding. Figure 2 shows segment 30 having an indexing pin 31 which is, in the example chosen the segment positioned at 2 o'clock. The other three segments have exactly the same shape, but does not have an indexing pin.

In the next stage of assembly, more particularly illustrated in Figure 3, we screw sockets 50 from the outside in the passages threaded through 35 segments 30. These sockets have a tube part smooth 54, having for length substantially the thickness of the casing circle 40, a portion of threaded tube 55 having a length substantially the thickness a segment 30 at the threaded through hole 35, a first shoulder 56 and a second shoulder 57 used to guide so known the pusher head, the sealing of which is ensured at this level by a seal 58 housed in a groove formed inside the socket. We will observe also that, in a known manner for mounting a pusher, the passage through the bushing to a larger inside diameter on the side of the head push button so as to be able to accommodate a return spring 59.

When we screw a socket 50, we not only position with precision a segment 30 to allow the assembly of the other parts, but still the shoulder 56 compresses a ring 26 on the periphery of the opening 26. Given the ductility of the noble metal, such as gold, forming the middle, this screwing operation deforms the middle according to a ring 26 and provides a satisfactory seal, without the need to provide for the interposition of a joint.

It is therefore clear that the segments 30 and the sockets 50 which come to block them are essential for the construction of the watch chronograph according to the invention, not only in terms of water resistance, but also at the level of the assembly of the other components, starting with the casing ring 40. In the above, it is obvious that we can by example reverse two assembly steps: first block the segments 30 with the sockets 50, then set up the socket ring 40.

Whatever the assembly order followed so far, it suffices to engage in the casing circle the movement 5 preassembled with its dial 6 and its display 7, 8. This assembly is blocked by a flange 9 engaged in a recess 49 of the socket circle and fixed by a screw 10. The stages of dial 6 and movement 5 are positioned by annular shoulders 46a, 46b, of the socket circle 40. It then suffices to engage the rod pusher 2 in the sockets 50, this operation having been anticipated in the representation of Figure 3. This assembly being conventional and not in itself part of the invention will not be described further. Similarly, we put in place the time setting rod 4, being observed, referring to the Figure 5 that it is guided only by a guide tube 3a having the same thickness as the wall 18 of the middle part and extending the opening 3, and that there is therefore no need to reinforce the recess of the middle there. This time-setting rod passes through the passage crossing 43 of the casing circle 40 and has a groove inside which is disposed a seal 58 bearing against the internal surface of the guide tube 3a.

The assembly continues with the installation of an ice seal 11 which is compressed radially by placing the glass 12 against the edge curved 22 of the middle-bezel 20, that is to say indirectly against the casing ring 40.

In a last step, the bottom is screwed, which includes a ring 14 having a thread towards the outside corresponds to the thread 44 of the nesting circle, said ring being extended by a ring 17 provided near its periphery of a groove 15 to receive a seal which is compressed axially against an annular part 27 of the bottom of the middle part-bezel 20, this which ensures sufficient tightness even when the recess 19 does not includes no segment, as shown in Figures 5 and 6.

Claims (7)

Noble metal chronograph watch including a box (1), closed by a crystal (12) and a bottom (13) resting on a middle-bezel (20) rigid having a recess (19) open towards the center of the box and in which are provided with through passages (3, 25) for a setting rod time (4) and for bushings (50) for guiding at least two pushers (2), and a chronograph movement (5) with its display device (6, 7, 8) positioned in said box by a casing circle (40) disposed between said movement (5) and said middle-bezel (20), characterized in that that the guide bushings (50) comprise a threaded tube (55) on the outside and terminated by a flange (56) and in that at least two segments (30) disjoint, shaped substantially like the recess (19) and pierced with a hole threaded (35) are arranged in line with the bushings (50) of the plunger (2) for allow by screwing from the outside to ensure both a firm positioning of said segments (30) and sealing at said level bushings (50) by crushing a metal ring (26) of the middle part (20) around the through passages (25). Chronograph watch according to claim 1, characterized in that one of the segments (20) has in its upper part on the glass side (12) a pin (31) whose head (39) protrudes from the face (34) of said segment oriented towards the center of the box (1) to cooperate with a notch (41) formed in the upper part of the socket circle (40) to index its position relative to the openings (3, 25, 35) made in the middle-bezel 20 in the segments (30). Chronograph watch according to claim 1, characterized in that each segment (30) further comprises, in its face facing the center of the box and along a plane parallel to the bottom, a groove (38) in which engages by unscrewing the head of an eccentric head screw (48) previously screwed into a housing in the wall of the socket circle (40) by making said nesting circle (40) integral with the segments (30) and of the middle part (20). Chronograph watch according to claim 1, characterized in that the casing ring (40) comprises in its part facing the center of the box a thread (44) which cooperates with the thread (14) outside of a ring secured to the bottom (13), said bottom (13) being extended radially by a ring (17) extending under an annular portion (37) of the lower part of the middle part (20). Chronograph watch according to any one of claims 1 to 4, characterized in that it comprises four pushers (2) and four segments (20) arranged in time positions 2, 4, 8 and 10 occupying 50 at 60% of the recess of the middle-bezel. Chronograph watch according to claim 1, characterized in that the segments (20) are made of brass. Chronograph watch according to claim 1, characterized in that the middle-bezel (20) and the back (13) are in gold and that they have a thickness between 300µm and 600µm, preferably 400µm.

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