Vacuum die-casting system, and method for operating a vacuum die-cast system

1. A vacuum die-casting system comprising

a casting chamber having a filling opening and an inner wall,

a casting piston able to be moved in the casting chamber and having an outer mantle, and

a piston rod connecting the casting piston with a casting drive,

wherein a ring gap is configured between the outer mantle of the casting piston and the inner wall of the casting chamber, and

wherein the casting piston has at least one depression or hollow standing in a flow connection with the ring gap and able to be evacuated, and

further comprising an evacuator able to evacuate the at least one depression or hollow, and

further comprising at least one collection depression standing in a flow connection with the ring gap and with the at least one depression or hollow,

wherein the at least one collection depression is disposed in front of the at least one depression or hollow.

2. The vacuum die-casting system according to claim 1 , wherein the at least one depression or hollow is configured in the casting piston itself.

3. The vacuum die-casting system according to claim 1 , further comprising at least one work piece placed behind the casting piston,

wherein the at least one depression or hollow is configured directly or indirectly behind the casting piston via the placement of the at least one work piece behind the casting piston, and

wherein due to the placement of the at least one depression or hollow the at least one depression or hollow can be brought into a region of the casting chamber via moving the casting piston into the casting chamber, before the at least one depression or hollow is evacuated and when the region of the casting chamber is not filled with casting melt.

4. The vacuum die-casting system according to claim 3 , further comprising a second work piece spaced apart from the casting piston in a manner so that the at least one depression or hollow is formed between the casting piston and the second work piece or between the second work piece and the at least one work piece.

5. The vacuum die-casting system according to claim 3 , wherein the at least one work piece is a ring.

6. The vacuum die-casting system according to claim 1 , wherein the casting piston is:

configured in multiple parts, or

configured in multiple parts and is solid, or

configured in one part, or

configured in one part and is solid, or

is solid.

7. The vacuum die-casting system according to claim 1 , wherein at least one of

the at least one collection depression and

the depression or hollow is configured as a depression surrounding at least one outer mantle selected from a group consisting of

the outer mantle of the casting piston,

an outer mantle of the piston rod, and

an outer mantle of the work piece.

8. The vacuum die-casting system according to claim 1 , further comprising at least one work piece placed behind the casting piston,

wherein the at least one depression or hollow is provided only in an upper outer mantle region of at least one of the outer mantle of the casting piston and an outer mantle of the at least one work piece.

9. The vacuum die-casting system according to claim 1 , further comprising at least one work piece placed behind the casting piston,

wherein the at least one depression or hollow comprises multiple depressions or hollows spaced apart from one another in a circumferential direction of at least one of the casting piston, the piston rod, and the at least one work piece.

10. The vacuum die-casting system according to claim 1 , wherein the at least one depression or hollow is dimensioned and can be evacuated in a manner so that during evacuation of a casting mold cavity connected to the casting chamber or during evacuation of the casting chamber, less to no gases or air flow(s) into the casting chamber through the ring gap.

11. The vacuum die-casting system according to claim 1 , wherein the evacuator comprises a vacuum, and

wherein the vacuum can be applied to the at least one depression or hollow so that during evacuation of a casting mold cavity connected to the casting chamber or during evacuation of the casting chamber, less to no gases or air flow(s) into the casting chamber through the ring gap.

12. The vacuum die-casting system according to claim 1 , wherein the evacuator comprises a vacuum system and at least one longitudinal recess within the piston rod and having a first end and a second end,

wherein the first end of the at least one longitudinal recess is connected, in terms of flow technology, with the at least one depression or hollow, and

wherein the second end of the at least one longitudinal recess is connected with the vacuum system, in terms of flow technology.

13. The vacuum die-casting system according to claim 1 , wherein the evacuator comprises at least one coolant line or bore contained in the piston rod.

14. The vacuum die-casting system according to claim 1 , wherein the evacuator comprises a vacuum system and at least one suction pipe having a first end and a second end,

wherein the first end of the at least one suction pipe is connected with the at least one depression or hollow in terms of flow technology, and

wherein the second end of the at least one suction pipe is connected with the vacuum system, in terms of flow technology.

15. The vacuum die-casting system according to claim 14 , wherein the at least one suction pipe runs along the piston rod,

wherein the first end of the at least one suction pipe makes a transition into the at least one depression or hollow via a piston region or a work piece region facing the piston rod, and

wherein the at least one suction pipe is connected with the at least one depression or hollow in terms of flow technology.

16. The vacuum die-casting system according to claim 10 , wherein the evacuator comprises a vacuum system and at least one longitudinal recess in the piston rod,

wherein the evacuation occurs as the vacuum system forms a vacuum in the at least one depression or hollow via the at least one longitudinal recess,

wherein the vacuum formed in the at least one depression or hollow can be adjusted,

wherein a cross-section of the at least one longitudinal recess is selected to be so great that the vacuum is maintained over a predetermined period of time and during the predetermined period of time the casting chamber and the casting mold cavity are evacuated and a partial vacuum is maintained in the casting mold cavity, despite an existing leak between the at least one depression or hollow and a region disposed behind the at least one depression or hollow,

wherein a further ring gap proceeding from the at least one depression or hollow and leading to the piston rod is connected with the at least one depression or hollow via the region.

17. The vacuum die-casting system according to claim 1 , further comprising at least one suction pipe within the piston rod,

wherein the at least one suction pipe has an end making a transition into the at least one depression or hollow, and

wherein the at least one suction pipe is connected with the at least one depression or hollow in terms of flow technology.

18. The vacuum die-casting system according to claim 1 , wherein the vacuum die-casting system is a cold chamber vacuum die-casting system.

19. The vacuum die-casting system according to claim 1 , further comprising a first control and a vacuum system having a second control,

wherein the first control is connected with the second control, and

wherein via the connection between the first control and the second control a start signal is transmitted to the vacuum system for evacuation of the at least one depression or hollow.