HOISTING DEVICE

Abstract

The invention relates to a hoisting device (1), in particular for a vehicle, including a substantially vertical column forming a frame (2) and lifting means (6) movable alongside said column (2) under the action of the control, by adequate driving means (12), to cause a threaded rod (9) to rotate and a nut (13) integral with said movable lifting means (6) on which the load to be lifted is designed capable of resting to move along the latter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically shows a hoisting device, such as a column, according to the invention;

FIG. 2 schematically shows the lower end of the threaded rod provided with the extension ferrule designed removable;

FIG. 3 is a schematic cross-sectional view of the extension ferrule inserted onto the lower end of said threaded rod.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in FIG. 1 of the attached drawing, the present invention relates to a hoisting device 1, usually referred to as lifting column because of its frame 2, which is primarily formed by a base plate 3 topped by a vertically arranged guiding rail 4.

On this guiding rail 4 are movably fitted, namely thanks to adapted rolling elements, lifting means 6 in the form of a carriage 7 comprising in the front portion 1 several lifting arms 8 on which the load to be lifted is designed capable of resting.

Inside the guiding rail 4, often having a U-shaped general structure, vertically extends a threaded rod 9, which is shown in FIG. 2. The latter is hung, through its upper end 10, from the column head 11. In particular, this threaded rod 9 is rotationally mounted at the level of this column head 11, which also receives an electric driving motor 12 designed capable of acting on said threaded rod 9 in order to subject it to a rotation from which results the lifting and the lowering of the carriage. In fact, the latter is provided with a nut 13 fitted on said threaded rod 9.

In particular, according to the invention, this threaded rod 9 is provided, at its lower end 14, with an extension ferrule 15. As can be seen in FIG. 3, the latter is retractably inserted on this lower end 14 of the threaded rod 9.

Thus, though this extension ferrule 15 permits to extend this threaded rod 9, substantially over the full height of the column, so as to avoid a too important fall of the lifted load, it can nevertheless, in the event of breaking of said rod 9, be dismantled to allow an easy replacing of the wearing part, which the nut 13 corresponds to. Indeed, after removing this extension ferrule 15, there is sufficient room to authorize the removal of the nut 13 from the lower end 14 of said threaded rod 9.

Finally, though this extension ferrule 15 can be defined of a minimum height in order to allow this operation of removing the nut 13, it can also extend substantially over the full height between the lower end of the useful portion of the threaded rod 9 and the base plate 3, even the floor on which rests the hoisting device 1.

According to an exemplary embodiment, the extension ferrule 15 includes an inner thread 16 for its mounting through screwing onto the lower end 14 of the threaded rod 9. This extension ferrule 15 also includes means for controlling the rotation 17, for example in the form of openings into which can be inserted a tool in order to ensure the screwing and unscrewing operations. Of course, other removable connecting means can be contemplated. In particular, it can be contemplated to make this extension ferrule integral with the end of the threaded rod, after encasing on the latter, by means of pins, snap rings or the like.

As regards the dimensioning of the extension ferrule 15, it should also be noted that the latter is defined of such a length that, after screwing or encasing it onto the lower end 14 of the threaded rod 9, sufficient free space is preserved, under this extension ferrule 15, to allow its unscrewing or its bringing out of encasement with a view to its removal.

It should however be noted that this free space will, in all the cases, be chosen smaller than the maximum drop height laid on by the standards in the field.

As already mentioned above, this extension ferrule 15 will also be dimensioned so as to guarantee a perfect support of the lifted load in the event of an accidental breaking of the threaded rod 9.

Finally, as results from the preceding description, the present invention solves in a clever way the problem raised until now by the replacement of the wearing part corresponding to the nut on this type of hoisting device in the form of a column.

Claims

1. Hoisting device, in particular for a vehicle, including a substantially vertical column forming a frame and lifting means movable alongside said column under the action of the control, by adequate driving means, to cause a threaded rod to rotate and a nut integral with said movable lifting means on which the load to be lifted is designed capable of resting to move along the latter, wherein the threaded rod includes, at its lower end, a removable extension ferrule.

2. Hoisting device according to claim 1, wherein the extension ferrule includes an inner thread for its cooperation with the lower end of the threaded rod.

3. Hoisting device according to claim 1, wherein the extension ferrule includes means for controlling the rotation.

4. Hoisting device according to claim 3, wherein the means for controlling the rotation are formed by openings provided for in the extension ferrule.

5. Hoisting device according to claim 1, wherein the extension ferrule is designed capable of being encased onto the lower end of the threaded rod.

6. Hoisting device according to claim 1, wherein the extension ferrule is defined of such a length that, after screwing or encasing it onto the lower end of the threaded rod, sufficient free space is preserved, under this extension ferrule, to allow its unscrewing or its bringing out of encasement with a view to its removal.

7. Hoisting device according to claim 1, wherein the extension ferrule is defined of such a length that after having been removed, it leaves sufficient space to authorize the removal of the nut from the lower end of said threaded rod.

8. Hoisting device according to claim 2, wherein the extension ferrule includes means for controlling the rotation.

9. Hoisting device according to claim 8, wherein the means for controlling the rotation are formed by openings provided for in the extension ferrule.

10. Hoisting device according to claim 2, wherein the extension ferrule is defined of such a length that, after screwing or encasing it onto the lower end of the threaded rod, sufficient free space is preserved, under this extension ferrule, to allow its unscrewing or its bringing out of encasement with a view to its removal.

11. Hoisting device according to claim 3, wherein the extension ferrule is defined of such a length that, after screwing or encasing it onto the lower end of the threaded rod, sufficient free space is preserved, under this extension ferrule, to allow its unscrewing or its bringing out of encasement with a view to its removal.

12. Hoisting device according to claim 4, wherein the extension ferrule is defined of such a length that, after screwing or encasing it onto the lower end of the threaded rod, sufficient free space is preserved, under this extension ferrule, to allow its unscrewing or its bringing out of encasement with a view to its removal.

13. Hoisting device according to claim 5, wherein the extension ferrule is defined of such a length that, after screwing or encasing it onto the lower end of the threaded rod, sufficient free space is preserved, under this extension ferrule, to allow its unscrewing or its bringing out of encasement with a view to its removal.

14. Hoisting device according to claim 2, wherein the extension ferrule is defined of such a length that after having been removed, it leaves sufficient space to authorize the removal of the nut from the lower end of said threaded rod.

15. Hoisting device according to claim 3, wherein the extension ferrule is defined of such a length that after having been removed, it leaves sufficient space to authorize the removal of the nut from the lower end of said threaded rod.

16. Hoisting device according to claim 4, wherein the extension ferrule is defined of such a length that after having been removed, it leaves sufficient space to authorize the removal of the nut from the lower end of said threaded rod.

17. Hoisting device according to claim 5, wherein the extension ferrule is defined of such a length that after having been removed, it leaves sufficient space to authorize the removal of the nut from the lower end of said threaded rod.

18. Hoisting device according to claim 6, wherein the extension ferrule is defined of such a length that after having been removed, it leaves sufficient space to authorize the removal of the nut from the lower end of said threaded rod.