Abstract: A case middle/horn connection device for a watch, a method for attaching an attachment piece including at least one horn to a case middle and a case middle/horn assembly. The connection device includes an attachment piece including at least one horn having a first connector and a case middle having a second connector, the first connector being configured to cooperate with the second connector to attach the attachment piece to the case middle. The first connector includes a tongue with a recess. The second connector includes a groove with an undercut portion. The undercut portion is configured to lodge inside the recess of the tongue; and the case middle and the attachment are made integral when the undercut portion of the second connector is lodged in the recess of the tongue of the first connector.

Abstract: A method for attaching a horn to a watch case middle, a case middle/horn connection device and a case middle/horn assembly, the horn comprising a first connector and the case middle comprising a second connector having an undercut groove, the first connector cooperating with the second connector in order to attach the horn to the case middle. The method includes: a placing the first connector of the horn in contact with the second connector of the case middle such that one or more intermediate cavities are formed between the undercut groove and the first connector; a melting one portion of the horn so as to create a molten material; a filling, at least partially, the one or more intermediate cavities by displacement of the molten material; and solidifying the molten material in order to make the horn integral with the case middle.

Abstract: A case middle/horn connection device for a watch, a method for attaching an attachment piece including at least one horn to a case middle and a case middle/horn assembly. The connection device includes an attachment piece including at least one horn having a first connector and a case middle having a second connector, the first connector being configured to cooperate with the second connector to attach the attachment piece to the case middle. The first connector includes a tongue with a recess. The second connector includes a groove with an undercut portion. The undercut portion is configured to lodge inside the recess of the tongue; and the case middle and the attachment are made integral when the undercut portion of the second connector is lodged in the recess of the tongue of the first connector.

Abstract: A watch and a method of ultrasonic welding a bezel to the watch at a middle part. The watch includes: a middle part which, with a crystal, delimits a watch case, the crystal being bonded to a shoulder arranged in the watch middle part; and a bezel ultrasonically welded both to the crystal and to the watch middle part.

Abstract: Method of ultrasonic welding a watch crystal, the watch including a middle part which, with the crystal, delimits a watch case, the crystal including a top face oriented towards the user and an opposite bottom face oriented towards the watch cases, a digital display device being fixed to the bottom face of the crystal, a printed circuit board being disposed inside the watch case, underneath and remote from the digital display device, the digital display device being electrically connected to the printed circuit board by means of a zebra electrical connector, wherein, as the crystal is abutting on a shoulder arranged in the middle part, the ultrasounds are directed onto the shoulder to melt the shoulder and to lower the level of the crystal in the direction of the printed circuit board, so that the zebra connector is compressed between the digital display device and the printed circuit board.

Abstract: Watch comprising a middle part (2), which, with a crystal (4), delimits a watch case (1), the crystal (4) being bonded to a shoulder (10) arranged in the watch middle part (2), the watch being characterized in that it comprises a bezel (14) ultrasonic welded both to the crystal (4) and to the watch middle part (2). The invention also concerns method of ultrasonic welding a bezel (14) to the watch middle part (2).

Abstract: Method of ultrasonic welding a watch crystal (4), wherein the watch comprises a middle part (2) which, with the crystal (4), delimits a watch case (1), the crystal comprising a top face oriented towards the user and an opposite bottom face oriented towards the watch case, a digital display device (12) being fixed to the bottom face (10) of the crystal (4), a printed circuit board (26) being disposed inside the watch case (1), underneath and remote from the digital display device (12), the digital display device (12) being electrically connected to the printed circuit board (26) by means of a zebra-type electrical connector (30), the method being characterized in that as the crystal (4) is abutting on a shoulder (6) arranged in the middle part (2), the ultrasounds are directed onto the shoulder (6) to melt said shoulder (6) and to lower the level of the crystal (4) in the direction of the printed circuit board (26), so that the zebra connector (30) is compressed between the digital display device (12) and the