Device for filling containers of collapsible type

1. A device for filling a container of a collapsible type with a product in the form of powder or liquid, said container having a compartment which is defined by flexible walls and whose volume is dependent on the relative position of the walls and which communicates with the surroundings through a filling duct of the container, comprising

a valve housing with a filling tube, which is insertable into said filling duct of the container to supply a product to the compartment of the container through a product path which is defined by the valve housing and its filling tube,

a piston element arranged in the product path and comprising a valve body and, arranged downstream thereof, an end element,

the piston element being movable between a first position, in which the valve body abuts against a valve seat of the valve housing to block the product path and the end element is arranged in or adjacent to an outlet portion of the filling tube to counteract dripping,

and a second position, in which the valve body is displaced from the valve seat to open the product path and the end element takes a position, in which it defines, together with the outlet portion, a filling passage,

wherein the end element projects from the outlet portion of the filling tube when the piston element is arranged in the second position, and

a squeezing apparatus which is arranged to grip the filling tube and the filling duct when said filling tube is inserted in said filling duct to establish a seal between the filling tube and the filling duct,

said filling tube being made of a rigid material.

2. A device as claimed in claim 1 , in which said piston element further comprises a piston rod, the piston rod supporting the valve body and the end element.

3. A device as claimed in claim 1 , in which the piston element is movable between said first and second positions by axial displacement of said piston element.

4. A device as claimed in claim 2 , wherein the end element is exchangeably arranged in said piston element.

5. A device as claimed in claim 2 , wherein the valve body is exchangeably arranged in said piston element.

6. A device as claimed in claim 1 , wherein the end element is received in the outlet portion of the filling tube when the piston element is arranged in the first position.

7. A device as claimed in claim 1 , in which said filling passage has the form of a circumferential gap.

8. A device as claimed in claim 1 , in which the outer diameter of the end element is smaller than the inner diameter of the filling tube.

9. A device as claimed in claim 1 , in which said valve body supports a seal, which, when the valve body is arranged in said first position, abuts against the valve seat.

10. A device as claimed in claim 1 , in which the end element has the form of a truncated cone.

11. A device as claimed in claim 10 , in which the circumferential surface of the truncated conical shape of the end element is curved.

12. A device as claimed in claim 1 , in which the end element has a flat surface facing away from the filling tube.

13. A device as claimed in claim 12 , in which said flat surface has a profiled surface structure.

14. A device as claimed in claim 1 , in which the end element has a circular base.

15. A device as claimed in claim 1 , in which the end element has a base with the shape of a convex lens.

16. A device as claimed in claim 1 , in which said material is stainless steel.

17. A device as claimed in claim 1 , in which the squeezing apparatus comprises elastic engaging surface which are arranged to grip said filling tube and said filling duct.

18. A device as claimed in claim 1 , in which the valve housing and the filling tube further comprise a gas duct for supplying a gas to the container.

19. A device as claimed in claim 18 , wherein the supply of gas is arranged to be controlled independently of the position of the piston element.