摘要 |
Device for automatically adjusting the tension of a thread (2), said device acting on a thread-braking mechanism (4) and comprising: an oscillating body (11) including a lever (15) responsive to the tension of the thread (2) and adapted to provide a torque for restoring the torque produced by the tension of the thread. The device of the invention also includes an assembly (24) for converting the movement of the oscillating body (11) into a movement for urging the braking mechanism (4), so that an increased or reduced tension of the thread applied to the responsive member results in a reduced or increased braking force of the braking mechanism. According to the invention, the oscillating body (11) includes a counterweight (22) adapted to provide a torque which opposes the restoring torque, so that the responsive member is subjected to a resulting torque varying non-linearly in relation to the angular displacement of the oscillating body.
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