Abstract: A mechanical world timepiece having a transmission mechanism which allows the time display, such as, for example, a 12-hour hand and/or a 24-hour hand, to be directly adjusted with a turning ring having 24 time zones. The timepiece serves for the easily manageable adjustment of the time zone and the reading of the time in a different time zone. Operation could not be simpler. After a lever has been opened, the mechanism in FIG. 1 automatically engages. The gear rim (6), which is fixed with the turning ring, drives a vertical drive wheel (5), which is connected by a shaft to a clutch wheel (4). Once the pinion (4) is engaged, it drives one or two minute wheels (8, 9), which move a 12-hour wheel (10) and a 24-hour wheel (11) in a 1 h-cycle. The turning ring is thus easily turned to the desired destination at 12 h and the local time can immediately be read. Either the turning ring is now turned back to its original locality or the lever is simply closed.

Abstract: A mechanical world timepiece having a transmission mechanism which allows the time display, such as, for example, a 12-hour hand and/or a 24-hour hand, to be directly adjusted with a turning ring having 24 time zones. The timepiece serves for the easily manageable adjustment of the time zone and the reading of the time in a different time zone. Operation could not be simpler. After a lever has been opened, the mechanism in FIG. 1 automatically engages. The gear rim (6), which is fixed with the turning ring, drives a vertical drive wheel (5), which is connected by a shaft to a clutch wheel (4). Once the pinion (4) is engaged, it drives one or two minute wheels (8, 9), which move a 12-hour wheel (10) and a 24-hour wheel (11) in a 1 h-cycle. The turning ring is thus easily turned to the desired destination at 12 h and the local time can immediately be read. Either the turning ring is now turned back to its original locality or the lever is simply closed.

Abstract: A watch case with an interchangeable bracelet system includes a back with a neck to which a portion of a bracelet is removably coupled. A closure element closes the neck and pinches the bracelet against the back of the case. Preferably, the closure element is a ring that is attached to the back of the case by means of a bayonet device consisting of a lug that is inserted in a mating hollow. To prevent accidental separation of the closure element from the case, a compression joint may be placed in a seat provided in either the back of the case or in the closure element. The closure element compresses the joint and frictionally prevents accidental opening. The device enables the bracelet to be changed easily without tools.

Abstract: A watch case with an interchangeable bracelet system includes a back with a neck to which a portion of a bracelet is removably coupled. A closure element closes the neck and pinches the bracelet against the back of the case. Preferably, the closure element is a ring that is attached to the back of the case by means of a bayonet device consisting of a lug that is inserted in a mating hollow. To prevent accidental separation of the closure element from the case, a compression joint may be placed in a seat provided in either the back of the case or in the closure element. The closure element compresses the joint and frictionally prevents accidental opening. The device enables the bracelet to be changed easily without tools.

Abstract: The crystal-bezel unit (1, 20) allows dismantling of the timepiece from above and can be moved rotatingly relative to a caseband (4), where a joining gasket (10) including at least one active portion is disposed between the crystal-bezel unit and the caseband. An optional fixing means (20) holds the fixed and rotating units together.

Abstract: The watch case including a back cover, a caseband, a crystal, the peripheral zone of which entirely covers the caseband, a casing ring including at least one packing, a pair of supports facing one another fixed to the caseband and forming therewith a slot in which the crystal may be engaged and means for displacing the casing ring in order to compress the packing against the internal surface of the crystal and block said crystal against the supports. The crystal exhibits at least in its peripheral zone a spherical form of constant thickness. The upper surface of the caseband has the form of a part of a sphere the radius of which is substantially equal to that of the internal surface of the crystal. During assembly the internal surface of the crystal is made to slide over the upper surface of the caseband with a rotational motion resulting from the sliding of a spherical surface over part of a sphere.

Abstract: A watch case is described comprising a middle, a front plate and a back. The middle includes two concentric rings, an outer ring and an inner ring, with both being sandwiched between the front plate and the back. The inner ring provides support for the movement and the dial. The outer ring protects the watch and helps to enhance its appearance. The front plate and the outer ring are best made of hard material.