Device for keeping an inaccessible element to be stabilised stationary in a required angular position and use of the device in a machine for processing textile threads

A device designed to maintain stationary, in a required angular position, an item to be stabilized (30), inaccessible by conventional mechanical means, arranged on a device rotating through a bearing, using the attraction force of a multitude of pairs of magnets (31.1, 31.2) placed to face each other, with each pair comprising a magnet (33) integral with the item to be stabilized (30) and a magnet (34) integral with the fixed part,

• characterised in that
• at least two pairs of magnets (31.1, 31.2) are arranged near one another on supports (32, 34) of materials having low reluctance,
• the said pairs of magnets (31.1, 31.2) and the said supports (32, 34) form, when the item to be stabilized (30) is in the required angular position, a closed magnetic circuit (except for the air gap), with magnets (33, 34) placed in such a direction that their north and south poles successively alternate with one another along said magnetic circuit,
• said closed magnetic circuit is generally symmetrical with respect to an axis or a radial plane with respect to the axis of rotation of the rotating device,
• an item (37), sensitive to the magnetic field, is attached to the fixed part and placed inside the closed magnetic circuit which is formed when the item to be stabilized (30) is in the required angular position, and in the axis or the radio plane of symmetry of the said circuit,
• said sensitive item (37) supplies a logic output state corresponding to the “item to be stabilized in the required angular position” when the detected field is less than a predetermined maximum threshold, and a logic state corresponding to the “item to be stabilized being outside the required angular position”, when the detected field is greater than a minimum predetermined threshold.