The present invention relates to a mechanical stop and start system for a function of a timepiece, comprising a mass, mounted so as to be able to move on a frame, between a first and a second end position, these being defined respectively by a first stop and a second stop, said mass moving in a bistable manner, under the effect of gravity, tensioning a spring between the first and second end positions, and relaxing said spring between the second and first end positions.

The invention relates to a timepiece movement comprising at least first and second functions implementing the display of at least first and second pieces of information. According to the invention, the movement has a selection member comprising an actuator, at least one lever configured to take at least first and second positions, respectively corresponding to the first and second functions, and respectively corresponding to the creation of first and second kinematic connections, and a cam cooperating with the actuator and the at least one lever so as to create the first and second kinematic connections.

The timepiece includes a chronograph mechanism with a coupling device including an operating member and a switching member which can be switched alternately between two stable positions coupled state and uncoupled state. This timepiece includes a magnetic system formed of a first bipolar magnet fixed to the switching member, a second bipolar magnet fixed to the support of the switching device in order to continually offer a magnetic interaction with the first bipolar magnet, and at least one highly magnetically permeable element forming the operating member and able to undergo a reciprocating motion between two operating positions. The switching device is arranged so that, when the highly magnetically permeable element is in its first operating position, the two magnets generate between them a force of magnetic repulsion and so that, when the highly magnetically permeable element is in its second operating position, the two magnets generate between them a force of magnetic attraction.

The timepiece includes a chronograph mechanism with a coupling device including an operating member and a switching member which can be switched alternately between two stable positions coupled state and uncoupled state. This timepiece includes a magnetic system formed of a first bipolar magnet fixed to the switching member, a second bipolar magnet fixed to the support of the switching device in order to continually offer a magnetic interaction with the first bipolar magnet, and at least one highly magnetically permeable element forming the operating member and able to undergo a reciprocating motion between two operating positions. The switching device is arranged so that, when the highly magnetically permeable element is in its first operating position, the two magnets generate between them a force of magnetic repulsion and so that, when the highly magnetically permeable element is in its second operating position, the two magnets generate between them a force of magnetic attraction.

A mechanical stop and start system for a function of a timepiece, including a mass, mounted so as to be able to move on a frame, between a first and a second end position, which are defined respectively by a first stop and a second stop. The mass portion moves in a bistable manner, under the effect of gravity, tensioning a spring between the first and second end positions, and relaxing the spring between the second and first end positions.