Self-adjusting thread braking device for weft feeder units

摘要

The breaking device has a single truncated-cone braking body, supported by an elastic member coaxially and frontally with respect to a drum of a feed unit and is actuated by the elastic member so that it engages, with an elastic contact, against the drum along a circumference thereof which is smaller than the maximum circumference of the drum. The thread slides between the drum and the braking body and extends from a point of contact with the drum and braking body along a path which is inclined with respect to the axis of the drum, so that the tension produced by the braking body has at least one axial component which is discharged onto the braking body and is balanced by the elastic member. Increase in the tension on the thread produces, or tends to produce, by virtue of the corresponding increase in axial component, separation of the braking body from the drum with a corresponding self-adjusting braking action.