Container for propelling cosmetic pencils, process for assembling such container and propelling cosmetic pencil

1. A container for propelling cosmetic pencils, comprising:

a tubular holding body ( 4 ) having a first opening ( 4 a ) and a second opening ( 4 b ) opposite to the first one ( 4 a ) and presenting an inner surface;

a lead-holder ( 7 ) axially movable in the holding body ( 4 ) and having a seat ( 9 ) facing the first opening ( 4 a ) and designed to receive a lead ( 3 ) of cosmetic material;

a driving element ( 13 ) movable in rotation in the holding body ( 4 ) and having an operating portion ( 14 ) protruding from the second opening ( 4 b );

means for converting the rotation motion of the operating portion ( 14 ) into the axial motion of the lead-holder ( 7 );

wherein said converting means comprises a threaded body ( 12 ) being part of the lead-holder ( 7 ), and tabs ( 16 ) that are radially flexible in an elastic manner and integral with the driving element ( 13 ) and having threaded portions ( 17 ) in engagement with the threaded body ( 12 );

characterized in that the inner surface of the holding body ( 4 ) has an axial portion (C) of reduced inner diameter placed close to the tabs ( 16 ) to keep the threaded portions ( 17 ) of said tabs ( 16 ) against said threaded body ( 12 ) and ensure mutual engagement of the threads; said axial portion (C) having a conical shape diverging towards the second opening ( 4 b ).

2. A container as claimed in claim 1 , wherein the driving element ( 13 ) is of tubular shape, and the threaded body ( 12 ) is an externally threaded rod and inserted in the driving element ( 13 ).

3. A container as claimed in claim 1 , comprising axial ribs ( 5 ) internal to the holding body ( 4 ) and engaged in grooves ( 11 ) formed in the lead-holder ( 7 ) to prevent rotation of the lead-holder ( 7 ) in the holding body ( 4 ).

4. A container as claimed in claim 3 , wherein the axial ribs ( 5 ) substantially extend as far as the first opening ( 4 a ) to axially guide the lead ( 3 ) and prevent radial displacements of same.

5. A container as claimed in claim 4 , wherein the seat ( 9 ) for the lead ( 3 ) is delimited by a cylindrical wall ( 8 ); the grooves ( 11 ) being axial cuts formed in said cylindrical wall ( 8 ) and the axial ribs ( 5 ) being inserted in said axial cuts ( 11 ) and facing the inside of the seat ( 9 ).

6. A container as claimed in claim 1 , comprising snap-engagement means interposed between the driving element ( 13 ) and the holding body ( 4 ) and positioned close to the second opening ( 4 b ), to axially lock said driving element ( 13 ) relative to said holding body ( 4 ).

7. A container as claimed in claim 6 , wherein the snap-engagement means comprises first annular ridges ( 6 ) disposed on an inner surface of the holding body ( 4 ) and second annular ridges ( 19 ) disposed on an outer surface of the driving element ( 13 ).

8. A container as claimed in claim 1 , comprising an annular seal ( 21 ) interposed between the driving element ( 13 ) and the holding body ( 4 ) and positioned at the second end ( 4 b ).

9. A propelling cosmetic pencil comprising a container ( 2 ) as claimed in claim 1 and a lead ( 3 ) of cosmetic material mounted in the lead-holder ( 7 ).

10. A process for assembling a container for propelling cosmetic pencils comprising the following steps:

i) providing a holding body ( 4 ) having a first opening ( 4 a ) and a second opening ( 4 b ) opposite to the first one ( 4 a ) and presenting an inner surface;

ii) providing a lead-holder ( 7 ) having a seat ( 9 ) designed to receive a lead ( 3 ) of cosmetic material;

iii) providing a driving element ( 13 ) having an operating portion ( 14 );

iv) causing axial sliding of a threaded body ( 12 ) integral with the lead-holder ( 7 ) or the driving element ( 13 ), on threaded portions ( 17 ) of radially flexible tabs ( 16 ) integral with the driving element ( 13 ) or the lead-holder ( 7 );

v) axially inserting the driving element ( 13 ) and the lead-holder ( 7 ) through the second opening ( 4 b ) of the holding body ( 4 ), the seat ( 9 ) of the lead-holder ( 7 ) facing the first opening ( 4 a ) and the operating portion ( 14 ) of the driving element ( 13 ) being maintained in a position protruding from the second opening ( 4 b );

v′) bringing said tabs ( 16 ) close to an axial portion (C) of the inner surface of the holding body ( 4 ) having a reduced inner diameter, where the tabs ( 16 ) enter into contact with the inner surface which radially forces said tabs ( 16 ) towards the threaded body ( 12 ), thus ensuring mutual engagement of the threads; said axial portion (C) having a conical shape diverging towards the second opening ( 4 b );

vi) locking rotation of the lead-holder ( 7 ) in the holding body ( 4 );

vii) axially locking the driving element ( 13 ) on the holding body ( 4 ).

11. A process as claimed in claim 10 , wherein step vi) is carried out through engagement, by axial movement, of axial ribs ( 5 ) internal to the holding body ( 4 ) in axial grooves ( 11 ) formed in the lead-holder ( 7 ).

12. A process as claimed in claim 10 , wherein step vii) is carried out through snap-engagement, by axial movement, of first annular ridges ( 6 ) internal to the holding body ( 4 ) with second annular ridges ( 19 ) of the driving element ( 13 ).