Classifications

• • G—PHYSICS
  • G04—HOROLOGY
  • G04G—ELECTRONIC TIME-PIECES
  • G04G21/00—Input or output devices integrated in time-pieces
  • G04G21/04—Input or output devices integrated in time-pieces using radio waves
• • G—PHYSICS
  • G04—HOROLOGY
  • G04B—MECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS
  • G04B37/00—Cases
  • G04B37/0008—Cases for pocket watches and wrist watches
  • G04B37/0016—Cases for pocket watches and wrist watches with folding cover or folding bottom (hinge without spring)

Definitions

• the present invention relates to a watch case back and a method of manufacturing a watch case back.
• the present invention relates in particular to a watch case back, the internal face of which is provided with a decoration.
• the watch cases have a middle and a back which can be screwed or clipped onto the middle.
• the back must be able to be opened to access the movement of the watch, for example to replace the battery or for repairs or maintenance of the movement.
• Many luxury watch cases are fitted with a case-back, the aesthetic appearance of the internal face of which is neat.
• Watch case funds are known, for example, the internal face of which is provided with a decoration, for example a pattern marked by engraving or by guilloche in the thickness of the metal.
• Watch case backs are most often produced by stamping.
• the internal face of the watch case backs is generally concave and has recesses or threads for fixing to the middle part and for maintaining the seal. It is therefore difficult to automate the decoration of this face. For this reason, the decoration of the internal face of the bottom is most often carried out manually.
• the highly appreciated guilloche background patterns are generally made using a special chisel and a small hammer in order to mark more or less regular circles in the thickness of the background. These operations are very expensive.
• An object of the present invention is to provide a watch case back and a method of manufacturing watch case back which has the same aesthetic qualities as known decorated watch case bottoms but which can be manufactured at a lower cost.
• watches are already known which contain an identification element, for example a transponder, interrogable by means of an inductive reading device.
• Transponders are used in particular to store information giving access to protected areas, for example as an element of identification in a company or as a cinema entrance ticket or for ski lifts.
• the identification element therefore makes it possible to replace or supplement the serial number traditionally engraved on the bottom of watch cases.
• the antenna of the transponder is generally mounted just on or under the dial or sometimes in the bezel; these provisions, however, cause significant constraints, given the small volume available in a watch, and do not allow the marking of watches comprising a metal case. Furthermore, the antenna is generally visible, which is unattractive, and is exposed to shocks or vibrations. For these reasons, an arrangement of the transponder against the internal face of the watch back would be preferable. This provision is however incompatible with decorated watch case backs. Furthermore, the transponder and in particular its antenna may be damaged when the bottom of the box is opened without care.
• Another object of the present invention is therefore to propose a watch case back which makes it possible to incorporate a transponder or another identification element.
• aims are achieved by means of a watch case back and a manufacturing process having the claimed characteristics.
• these aims are achieved by means of a watch case back comprising a cover defining the external face of the back, and a false back mounted against the internal face of said cover.
• This solution has the advantage of separating the manufacture of the cover, which frequently requires stamping operations, tapping, etc., from the manufacture of the false bottom which requires other simpler stamping operations (cutting) and operations. decoration. It is thus possible to optimize the processes used for the manufacture of these two elements.
• the false bottom by cutting from a plate of regular thickness previously decorated.
• the decoration of a plate of regular thickness can be automated and carried out using a machine
• the decoration can for example be carried out by etching in the thickness of the plate.
• This solution also has the advantage of allowing an electronic identification element to be placed between the cover and the false bottom.
• This identification element can be completely hidden between the cover and the false bottom. It does not harm the internal or external aesthetics of the watch and is perfectly protected from any damage, even if the case is opened.
• the false bottom contributes to increasing the solidity and the rigidity of the bottom; it is thus possible to reduce the thickness of the cover, which offers the advantage of facilitating inductive reading through the bottom. This advantage is particularly important in the case of a metal watch case back which significantly attenuates the radio waves transmitted to and from the transponder.
• CH 335610 describes a watch having a back, that is to say an element closing the middle part in a removable manner, on the external face of which is added a synthetic lining, intended mainly to protect the watch from marks in the event of contact with bodies foreigners.
• This trim is however not comparable to the false bottom of the present invention.
• this lining is located on the external face of the back of the watch and not on its internal face. It can thus in no way contribute to the reduction of the costs generated by the decoration of the internal face of the back of the watch.
• US 1404656 describes a watch whose box consists of an outer precious metal box reinforced, among other things, by an inner box made of a less expensive material.
• the case of this watch does not, however, have a back allowing easy access to the movement without removing it from the case.
• the internal box is completely hidden by the external box and does not fulfill any aesthetic function.
• Figure 1 is a sectional view of a raw plate for the manufacture of several false bottoms according to the invention.
• Figure 2 is a sectional view of the same plate during the decoration operation by engraving the upper face.
• Figure 3 is a top view of the plate after decoration, showing a guilloche pattern.
• Figure 4 is a sectional view of the plate during the stamping cutting operation.
• Figure 5 is a top view of a false bottom of a watch decorated and cut according to the invention.
• Figure 6 is a partial sectional view of a watch case provided with a first variant of the watch case according to the invention.
• Figure 7 is a partial sectional view of a watch case provided with a second variant of the watch case according to the invention.
• Figure 1 shows a plate 1 of regular thickness intended to manufacture in a reduced number of operations a plurality of decorated watch case false bottoms.
• the plate is preferably made of metal, preferably in the same metal as that used for the back of the watch.
• the visible upper face of the plate is decorated in a single operation, for example by means of a stamp 2 supported on the entire surface of the plate 1 and provided with a punch 20 (FIG. 2).
• the size of the stamp 2 can correspond to that of the plate 1, as illustrated in FIG. 2, or be smaller and applied in several times. It is also possible to engrave the upper surface of the plate 1 by passing it between two rollers, one of which is provided with a relief pattern, or to apply a decoration to the plate 1 by another method, for example by screen printing, plating, eloxidation, etc. However, it is preferable to choose a surface treatment of the plate identical to that used for the other parts of the bottom, so as to make the use of a false bottom as little visible as possible.
• FIG. 3 illustrates the upper face of the decorated plate 1.
• the pattern 10 affixed by stamping resembles the known guilloche patterns.
• the plate 1 is then cut, preferably by means of a punch 3 as illustrated in FIG. 4. It is naturally also possible to cut several false bottoms simultaneously in the same plate, and / or to cut and decorate the plate 1 in one operation and at using the same stamp. It is also possible to carry out several separate decoration operations on the same plate 1.
• machining operations not shown can be performed on the false bottom 11, for example in order to mill a recess (visible in FIGS. 6 and 7) intended to house an electronic component, for example an element of identification 5 and a coil 6.
• This recess can also be obtained by stamping. It is also possible to deform the underside of the false bottom by stamping in order to adapt it to the internal shape of the cover.
• FIG. 5 illustrates a top view of a false back 11 of a watch decorated with a guilloche pattern 10.
• FIG. 6 illustrates a partial section of a watch case comprising a middle part 7 and a back 11, 4 according to a first variant of the invention.
• the bottom comprises a cover 4 and a false bottom 11 manufactured according to the method described above.
• the cover and the false bottom are provided with holes for screws 40 for fixing to the middle part 7.
• a seal 70 makes it possible to prevent water infiltration between the middle part and the bottom.
• an identification element constituted here by a transponder 5 provided with an antenna 6 is housed in a recess between the false bottom 11 and the cover 4.
• the thickness of the cover 4 is preferably reduced in order to limit the attenuation of the electromagnetic field through this wall.
• the antenna 6 is constituted by a coil formed by winding a copper wire and connected by bonding directly on the legs of the circuit 5.
• the circuit 5 can be fixed in the recess by means of a double-sided adhesive film stamped to the size of the adhesive housing.
• the circuit 5 placed on the self-adhesive film is transported by suction to be deposited at the bottom of the housing. We will watch everything particularly during this operation to avoid breaking the antenna wire and we can if necessary verify the proper functioning of the identification element 5 by reading its content after installation.
• the circuit 5 can also be coated with resin. Conclusive tests have been carried out by delivering by means of a metering device a precise quantity of very pure epoxy resin. In order to ensure that the resin spreads out perfectly by filling the entire recess, it is possible to use a centrifuge or a vibrating machine during the polymerization of the resin.
• the identification element 5 is preferably supplied electrically only by the inductive writing and / or reading-writing device used to access the stored data, without requiring the watch battery. It includes a not shown modulator-demodulator for receiving and demodulating the signals from the inductive read-write device, and for modulating and transmitting the responses.
• the circuit 5 preferably uses a frequency significantly lower than those usually used for standard RFID elements, preferably a frequency less than 50 KHz, in order to allow transmission through the metal.
• An encryption and / or electronic signature module can also be provided in circuit 5 in the case where confidential data, for example medical data or monetary amounts must be stored in one or more fields of the memory area.
• the circuit 5 preferably includes a memory area, not shown, including a program area and a data area.
• the watch back can thus be personalized by writing in the data area of the manufacturer and / or retailer data (serial number, date of manufacture, batch number, etc.). Personalization can be carried out by the watch manufacturer after mounting the case back on the watch or more simply by the case manufacturer before assembling the watch, based on the data and serial numbers provided by the watch manufacturer for example on diskette or via e-mail.
• the memory area can also be modified by application providers after the sale of the watch, for example to write access codes to protected areas.
• the serial number of the watch is also engraved on the external face of the caseback. This feature allows you to check the serial number of the watch without a special reading device.
• Figure 7 illustrates a second variant of the watch case back provided with a false back 1 1 according to the invention.
• the cover is provided with a peripheral thread 41 allowing it to be screwed directly into the middle part 7.
• a seal 42 taken between the middle part 7 and a projection 42 of the cover makes it possible to avoid water infiltration.
• the false bottom 1 1 is placed on the cover 4 and fixed for example by gluing.
• An identification element 5, 6 can be placed between the cover 4 and the false bottom 11.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Electric Clocks (AREA)

Applications Claiming Priority (3)

Publications (3)

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Family Applications (1)

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Family Cites Families (22)

• 2002
  • 2002-07-17 EP EP02740191A patent/EP1470453B8/de not_active Expired - Lifetime
  • 2002-07-17 WO PCT/CH2002/000397 patent/WO2003052526A1/fr active IP Right Grant
  • 2002-07-17 AU AU2002315622A patent/AU2002315622A1/en not_active Abandoned
  • 2002-07-17 US US10/527,817 patent/US20060104161A1/en not_active Abandoned
  • 2002-07-17 DE DE60223723T patent/DE60223723T2/de not_active Expired - Fee Related

Non-Patent Citations (1)

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