EP0400449B1 - Time-piece with a simplified exterior - Google Patents

Abstract

The time-piece comprises a ring (6) which performs a fourfold function: that of leaktight seal between the glass (1) and the ring, that of fastening the middle part (3) to the ring, that of caging circle for the movement (5) and, finally, that of fastening the back (2) to the ring. To this end, the middle part has a cylindrical inner wall (4) entirely covered by the ring, the said ring having a first housing (8) in which the glass is engaged, a second housing (10) in which the movement is engaged and a lower zone (11) comprising means (18, 19) for fastening the back. <IMAGE>

Description

The present invention relates to a timepiece comprising a crystal, a bottom and a middle part having a cylindrical internal wall, the crystal, the bottom and the middle part together defining a box intended to receive a movement provided with display means.

To simplify the assembly and disassembly of a timepiece comprising a box enclosing a movement, the document CH-A-554 560 (GB-A-1.370.528) has already proposed a construction where the glass and the bottom constituting constituent parts of the box are assembled in a single middle in which they are driven with interposition, between the edge of each of them and said middle, of a lining ensuring, on the one hand, the sealing and, on the other hand, keeping them in place, the inner surface of the middle part in which the crystal and the bottom are engaged being cylindrical and therefore having no bearing shoulder.

To achieve this result, the construction cited uses, apart from the fittings mentioned, two additional rings and a spacer forming a casing circle and separating said fittings, therefore to a plurality of parts manufactured independently of one another, which 'then stack one on top of the other when mounting the box. This leads to a multiplicity of relatively expensive tools which increase the final cost of the box as is also increased the time spent on assembly. Mention will also be made of the use, for this assembly, of two relatively complicated layouts which must be specifically adapted to the box to be assembled.

Document DE-A-34 21 168 describes a tubular lining comprising a projection reducing its internal diameter. However, in this construction, the middle part does not have a continuous cylindrical internal wall since a shoulder is provided in the bottom of the middle part, shoulder on which the lining comes to bear. This arrangement complicates the rapid assembly or disassembly of the watch and especially the way of making the middle whose internal wall is not continuous.

To avoid the drawbacks listed above while retaining the advantage of using a middle part with a cylindrical internal wall therefore having no bearing shoulder, the timepiece of the present invention is characterized in that a ring is disposed between, on the one hand, the internal wall of the middle part which it completely covers and, on the other hand, the crystal and the movement, said ring comprising an upper zone having a first housing in which at least the glass is engaged, said glass compressing against the middle part the material from which the ring is made to ensure both a tight closure between the glass and said ring and the fixing of said ring on the middle, a central zone having a second housing in which the movement is engaged, said ring serving as a casing circle for said movement, and a lower zone emerging from the middle part, said lower zone comprising means for fixing the bottom to said ring.

• les figures 1 à 7 sont des vues en perspective éclatée de la pièce d'horlogerie selon l'invention présentant toutes les parties constitutives de ladite pièce et montrant leur ordre d'assemblage. En particulier,
  • la figure 1 est une bague d'assemblage,
  • la figure 2 est une garniture d'étanchéité,
  • la figure 3 est un fond,
  • la figure 4 est un mouvement muni de ses moyens d'affichage,
  • la figure 5 est un réhaut,
  • la figure 6 est une carrure pourvue de cornes pour l'attache d'un bracelet,
  • la figure 7 est une glace,
  • la figure 8 est une coupe selon la ligne VIII-VIII montrée en figure 1, en supposant la pièce d'horlogerie complétement montée,
  • la figure 9 est une coupe selon la ligne IX-IX montrée en figure 1, en supposant la pièce d'horlogerie complétement montée et,
  • la figure 10 est une coupe d'un autre mode d'exécution que celui montré en figure 9.

The invention will now be explained by means of the following description, illustrated by way of example in the drawing in which:

• Figures 1 to 7 are exploded perspective views of the timepiece according to the invention showing all the constituent parts of said part and showing their order of assembly. In particular,
  • FIG. 1 is an assembly ring,
  • FIG. 2 is a seal,
  • Figure 3 is a background,
  • FIG. 4 is a movement provided with its display means,
  • FIG. 5 is a flange,
  • FIG. 6 is a middle part provided with horns for attaching a bracelet,
  • FIG. 7 is a mirror,
  • FIG. 8 is a section along the line VIII-VIII shown in FIG. 1, assuming the timepiece completely assembled,
  • FIG. 9 is a section along the line IX-IX shown in FIG. 1, assuming the timepiece completely assembled and,
  • FIG. 10 is a section through another embodiment than that shown in FIG. 9.

If we now refer to FIG. 9, and to the perspective figures, we see that the timepiece comprises a crystal 1 (FIG. 7), a base 2 (FIG. 3) and a middle part 3 (FIG. 6) , the crystal, the bottom and the middle part together defining a box intended to receive a movement 5 (FIG. 4) provided with display means illustrated by a dial 13 and hands 25. More particularly, the middle part 3 has a cylindrical internal wall 4, which means that this wall has no recess or support shoulder. This feature is very interesting, because it makes it possible to manufacture the middle part in a single operation and without subsequent recovery.

According to an essential characteristic of the invention, a ring 6 (Figure 1) is disposed between, on the one hand, the internal wall 4 of the middle part 3 and, on the other hand, the crystal 1 and the movement 5. The wall internal 4 of the middle part is entirely covered by this ring. As can be seen in Figures 1 and 9, the ring 6 has an upper area 7 having a first housing 8 in which at least the glass 1 is engaged. When the glass is engaged in its housing, the material from which the ring is made is compressed against the middle part 3. Thanks to this, a tight seal is ensured between the glass and the ring as well as the fixing of the ring to the middle. The ring 6 also has a central zone 9 having a second housing 10 in which the movement 5 is engaged, the ring thus serving as a casing circle for the movement. The ring 6 finally comprises a lower zone 11 which emerges from the middle part 9. In this lower zone 11 are made means for fixing the base 2 to the ring 6, as will be explained in more detail below.

Thus, according to the explanations which have just been given, the ring 6 has a quadruple function: that of first ensuring the tight closure of the top of the case, as well as that of securing the middle part on the box, that then to serve as a casing circle for the movement and finally that to have means for securing the bottom to the box. It thus combines functions which, in the prior art, were fulfilled by several separate parts from each other, which simplifies considerably assembling the timepiece. This ring, made in one piece, is easy to make even within tight tolerances; it is simple and inexpensive. A plastic material which is sufficiently compressible to ensure a good seal between the crystal and the case will be chosen to make it, this material however remaining hard enough to ensure good hold of the middle as well as good movement guidance.

In the embodiment appearing in the figures, the first housing 8 receives, in addition to the glass 1, a flange 12 (FIG. 5) which provides a well-defined space between the glass and the dial 13 surmounting the movement 5. The outside diameter of the flange is arranged so that said flange can be freely introduced into the housing 8. As can be seen in FIG. 8, the flange presses on a shoulder 34 whose thickness corresponds substantially to the thickness of the dial 13. The rotation of the dial is prevented by practicing, in extension of the shoulder 34, two projections 33 (Figures 1 and 9) which are introduced into two cutouts 32 made in the dial (Figure 4).

Still in the embodiment shown in the figures, the second housing 10 is adapted to the movement 5 which is introduced. In particular, as can be seen in FIG. 9, the movement 5 is provided with a flange 35 resting on a battue 36 made in the second housing 10.

If the movement with its display means are mounted as described above, one can refrain from using the means generally used for such mounting. This is how we can avoid the use of dial feet and movement fixing flanges to the ring as is commonly the case.

In the construction shown in FIGS. 8 to 10, it can be seen that the lower zone 11 of the ring 6 has a third housing 14 in which a lining 15 is housed (FIG. 2). When the base 2 is applied under the ring, the lining 15 is compressed and thus ensures a tight closure between the base 9 and the ring 6.

Comments will now be made on how to fix the bottom 2 on the ring 6. Two non-limiting embodiments are shown respectively in Figures 9 and 10. In Figure 9 the bottom 2 has a flange 19 which is hooked on a notch 18 presented by the ring 6. In FIG. 10 the bottom 2 is screwed by means of screws 22 into the ring 6. The attachment by notch or the fixing by screw of the bottom on the ring could be done on a ring made entirely of material. plastic. However, such a solution would be mechanically insecure, because the plastic material can be subject to creep, and above all unreliable if we consider that the bottom, itself made of metal, must be removed several times, would as for the replacement of the battery, if movement 5 is a quartz movement.

Thus, to improve the construction, Figures 9 and 10 show that the ring 6 comprises the combination of a first circle 16 made of plastic with a second circle 17 made of metal, these two circles being integral with one of the other and forming only a ring 6. The first circle 16 of plastic material is arranged to form the housings 8 and 10 respectively receiving the glass 1 and the movement 5 as described above. Incidentally, the figures thus show that in the first circle is formed the housing 14 receiving the lining 15. The second circle 17, made of metal, at least partially occupies the lower zone 11 of the ring 6 emerging from the middle part 3. The means for fixing the bottom 2 to the ring 6 are made in the second circle 17.

In the embodiment of FIG. 9, the means for fixing the bottom comprise a notch 18 formed in the periphery of the second circle, notch in which a flange 19 lifted is raised in the bottom 2. This same figure also shows that the underside 20 of the middle rests on the rim 19 of the bottom 2. This arrangement will make it possible to precisely position the middle 3 with respect to the ring 6 and thus avoid the use of a special fitting as was the case in the document cited above.

In the embodiment of FIG. 10, the means for fixing the bottom comprises tappings 21 (generally four) made in the second circle 17, tappings in which screws 22 are screwed through holes 23 made in the bottom 2. This same figure also shows that the underside 20 of the middle rests on a projection 24 presented by the periphery of the second circle, this provision having the same advantages as those discussed in the paragraph above.

For each of the two embodiments discussed above, it will be understood that the combination of the circles 16 and 17 can be obtained by molding the first plastic circle on the second metal circle to then obtain a ring 6 made in one piece. To do this, we see that the metal circle 17 has a shoulder 37 extending towards the movement, shoulder intended to ensure the anchoring of the circles on one another.

Whatever the embodiment adopted, FIGS. 1 and 8 show that a passage 27 is made in the circle 16 of plastic material, passage having a tube 26 emerging from the ring 6. In this passage 27 is introduced a rod 28 time reset once the timepiece is assembled. The middle part at this location (see also FIG. 6) has a housing 31 into which the crown 38 of the rod 28 can penetrate, when the rod is in the normal depressed position.

Figures 1 to 7 have been numbered according to a preferred order of assembly of the parts relative to each other. To carry out this mounting, the ring 6 of FIG. 1 is grasped, a ring produced for example according to the section shown in FIG. 9. The gasket 15 of FIG. 2 is introduced into the housing 14 of the ring 6. Apply the bottom 2 of Figure 3 under the ring until the flange 19 of the bottom are hooked on the notch 18 of the ring. We engage the top of the ring movement 5 of Figure 4 in the housing 10. On the movement we apply the dial 13, then we put the hands 25. On the dial 13 we put the flange 12 of Figure 5 which takes place in the bottom of the housing 8 of the ring 6. The middle 3 of figure 6 is slid along the peripheral wall of the ring until said middle comes to abut against the edge 19 of the bottom 2. Finally , by means of a press, the glass 1 of FIG. 7 is driven into the housing 8 of the ring 6 until said glass comes to bear on the flange 12.

From the description which has just been given, it can be seen that the timepiece of the invention is very simple to assemble and does not require any special tools or fitting. This system allows the manufacturer of parts making up the box to deliver to the assembler of the timepiece a pre-assembled assembly uniting the ring 6, the lining 15 and the base 2, which considerably reduces the number of parts present.

The assembly order indicated above could however be different, the lining 15 and the bottom 2 being able, for example, to be fitted last. In this case, however, at least one special fitting should be provided to position the middle part relative to the ring when the ice is expelled in said ring.

The timepiece produced according to FIG. 10 is assembled in the same way as that exposed above and no special fitting is to be expected whatever the assembly order chosen, since the ring has a projection 24 on which the middle 3 rests.

Claims (9)

1. Timepiece including a crystal (1), a back cover (2) and a caseband (3) exhibiting a cylindrical internal wall (4) without any support shoulder, the crystal, the back cover and the caseband together defining a case intended to receive a movement (5) provided with display means, characterized by the fact that a ring (6) is arranged between, on the one hand, the internal wall of the caseband which it overlays entirely, and on the other hand, the crystal and the movement, said ring including an upper zone (7) exhibiting a first accommodation (8) in which at least the crystal is engaged, said crystal compressing the material forming the ring against the caseband in order to assure at the same time a moisture tight closure between the crystal and said ring and the securing of said ring onto the caseband, a middle zone (9) exhibiting a second accommodation (10) in which the movement is engaged, said ring serving as a casing ring for said movement, and a lower zone (11) emerging from the caseband, said lower zone including means for securing the back cover to said ring.

2. Timepiece according to claim 1, characterized by the fact that a flange (12) is additionally engaged in the first accommodation in order to assure a predetermined space between the crystal and a dial (13) forming part of said display means.

3. Timepiece according to claim 1, characterized by the fact that the lower zone further includes a third accommodation (14) in which a packing (15) is housed in order to assure a moisture tight closure between the back cover and said ring.

4. Timepiece according to claim 1, characterized by the fact that the ring includes the combination of first (16) and second (17) circles bound to one another, the first circle being formed of plastic material and arranged to provide said first and second accommodations, the second circle being formed of metal and at least partially occupying said lower zone, said means for securing the back cover to said ring being arranged in said second circle.

5. Timepiece according to claim 4, characterized by the fact that the combination of said first and second circles is obtained by overmoulding of said first circle onto said second circle.

6. Timepiece according to claim 4, characterized by the fact that said means for securing the back cover include a snap (18) formed in the periphery of the second circle and an edge (19) on said back cover arranged and adapted to fasten onto said snap.

7. Timepiece according to claim 6, characterized by the fact that the bottom (20) of the caseband rests on the edge provided on the back cover.

8. Timepiece according to claim 4, characterized by the fact that said means for securing the back cover include threadings (21) arranged in the second circle in which are engaged screws (22) passing through holes (23) provided in the back cover.

9. Timepiece according to claim 8, characterized by the fact that the bottom (20) of the caseband rests on a projection (24) provided in the periphery of the second circle.

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