Mechanism for braking the unwinding of a bundle of metallic wire housed in a drum

Abstract

A circular crown shaped pressure disk (1), furnished with, on its external rim, jutting stirrup shaped, flexible elements (2) whose size makes them press on the internal surface of the drum (7) within which the disk is housed. The internal rim of the disk is equipped with winglets (3) and with flexible tabs (5) directed nearly tangentially in respect to the tubular trunk (8), placed at the center of the drum (7). The flexible tabs are for stopping the rise of the bundle of coils so as to impede their knotting and to help guiding the wire, as it is pulled to the outside of the drum and unwound from the bundle.

Description

AA 2-2 section line of FIG. 1;

FIG. 3 is the partial view along the BB 3-3 section line of FIG. 1;

FIG. 4 is the view on a different scale of a section of the drum with the invention inserted on it, sectioned with an axial plane.

However, it must be clear that the drawings and the corresponding described parts are given exclusively as the illustration of the object of the invention, without in any way constituting a limitation of it.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the drawings we have indicated with 1 the circular shaped crown structure, with 2 the stirrup shaped flexible elements, with 3 the shaped winglets, with 4 their external profile, with 5 the flexible tabs, with 6 the thin skeletons that connect the winglets 3 with the tabs 5, with 7 the drum, with 8 its central tubular trunk. In substance, the invention consists in a device capable of carrying out a braking and containing action in the unwinding of the metal wire wound into a bundle and placed inside a containing drum 7, having a tubular center 8. The wire being used to feed welding machines and in particular those operating non stop (welding robots).

Said device operates a braking action on the movement of the coils at the top of the bundle that is being unwound. It consists in an element which can carry out a slight pushing action on the coils and is formed by a circular crown 1 having on its outer edge distributed stirrup shaped flexible elements 2, with a dimension that allows their adherence—bending inwards if necessary—to the internal surface of the drum 7 in which the invention is positioned. In this way it can stop the external parts of the coils from rising along the internal surface of the drum 7 and to go over the level of the pressure disk itself and as a consequence of the pulling action, the wire could move close to the tubular trunk 8 and create a knot on the disk 1 with the effect of stopping its normal flow.

On its inner edge the disk 1 is equipped with distributed guiding winglets 3 and flexible tabs 5. The former having the profile 4 of the side oriented towards the axis of the drum 7, connected to the thin skeleton 6 curved into a spiral towards the center of the same drum, so that the wire of the bundle, when pulled, is evenly sustained and guided towards the center of the drum 7 to emerge from it staying adherent to the tubular trunk 8 against which it is pushed by the sequence of flexible tabs 5 that follow it as it unwinds.

The invention therefore carries out two actions, the first one consisting in a braking action that also regulates the movement of the coils at the top of the bundle, in fact said movement would be turbulent and disorganized without it. The second action is that of convoying the wire that unwinds making it emerge from the drum 7 in an almost axial direction as well as a rotary one to follow the coils that unwind from the bundle.

Claims

1. A device for braking the unwinding of bundled metal wire placed in a drum, for the feeding of welding machines having an automatic advancing movement of the wire, the device having a circular crown with jutting flexible elements on its outer edge for pressing on an inner surface of the drum, and further comprising guiding winglets and flexible tabs on an inner edge of the crown.

2. The device as claimed in claim 1, wherein said jutting flexible elements are stirrup-shaped.

3. The device as claimed in claim 1, wherein the winglets have a circular inner periphery, the inner periphery including a skeleton curved into a spiral towards a center of the crown.

4. The device as claimed in claim 1, wherein the flexible tabs are oriented in an almost tangential direction toward a circle interior to the inner edge of the crown and are for suppressing inadvertent release of the wire in the drum.

5. A device for braking the unwinding of bundled metal wire placed in a drum, for the feeding of welding machines having an automatic advancing movement of the wire, the drum having an internal surface, said device comprising a circular crown having an outer peripheral edge which is spaced from the internal surface of the drum which allows said device to descend with the unwinding of the wire, said device includes inwardly extending flexible tabs on an inner edge of said crown having a front edge facing the wire during the unwinding, said flexible tabs on said inner edge being at an angle less than 90 degrees from said inner edge, and the wire traveling along said front edge during the unwinding.

6. The device as described in claim 5, wherein said angle is less than 75°.

7. The device as described in claim 5, wherein the drum further includes a central cylindrical tubular trunk generally centered in the drum, said inner edge of said crown surrounding said tubular trunk and said inwardly extending flexible tabs having a length to engage said tubular trunk.

8. The device as described in claim 5, wherein said device further includes flexible elements on an outer edge of said crown, said flexible elements engaging the internal surface the drum.

9. A device for braking the unwinding of bundled metal wire placed in a drum, for the feeding of welding machines having an automatic advancing movement of the wire, the drum having an internal surface, said device comprising a circular crown having an outer peripheral edge which is spaced from the internal surface of the drum which allows said device to descend with the unwinding of the wire and includes flexible tabs on an inner edge of said crown and non-flexible guide winglets on said inner edge of said crown.

10. A device for braking the unwinding of bundled metal wire placed in a drum, for the feeding of welding machines having an automatic advancing movement of the wire, comprising a circular crown with flexible tabs on an inner edge of said crown and flexible elements on an outer edge of said crown, said flexible tabs on said inner edge being at an angle less than 90 degrees from said inner edge and said flexible tabs guiding the wire as it is unwound.

11. The device as described in claim 10, wherein said angle is less than 75°.

12. A device for braking the unwinding of bundled wire placed in a drum, for feeding of welding machines having an automatic advancing movement of the wire, the drum having a central cylindrical tubular trunk generally centered therein, said device comprising a circular crown with an opening substantially smaller than said tubular trunk and having an inner circular periphery whereby said crown surrounds said tubular trunk so said periphery defines an annular space around said tubular trunk with a given width and a plurality of flexible tabs extending at an angle less than 90 degrees from said periphery at circumferentially spaced positions, said tabs having a length to engage said tubular trunk at said angle when said crown is in said drum and as said wire is pulled from said drum between said tubular trunk and said flexible tabs.

13. The device as described in claim 12, wherein said angle is less than 75°.