Molding tool

1. A molding tool ( 1 ) for producing molded parts from expandable plastic beads, the molding tool ( 1 ) having an inner wall ( 10 ) facing the molded part and an outer wall ( 12 ) facing away from the molded part between which a hollow space ( 11 ) is configured to convey a heating/cooling medium (K), the inner and outer walls ( 10 , 12 ) are connected to each other in areas by spacers ( 13 ), inside the spacers ( 13 ) through bores ( 130 ) are formed and convey steam, wherein the through bores ( 130 ) pass through the outer and inner walls ( 10 , 12 ) and are sealed relative to the hollow space ( 11 ), wherein the molding tool is produced integrally in one piece out of sintered metal and the inner wall ( 10 ) comprises an inner surface facing the molded part and a multiplicity of capillary tubes extending through the inner wall connecting the inner surface to the hollow space ( 11 ), the capillary tubes configured to divert condensate from the inner surface into the hollow space ( 11 ).

2. The molding tool ( 1 ) according to claim 1 , wherein the spacers ( 13 ) are positioned at regular intervals from one another in the form of a grid.

3. The molding tool ( 1 ) according to claim 2 , wherein the spacers ( 13 ) function as flow dividers for the heating/cooling medium (K) that can be conveyed through the hollow space ( 11 ).

4. The molding tool ( 1 ) according to claim 3 , wherein the inner and outer walls ( 10 , 12 ) are oriented approximately parallel to each other and spaced a constant distance apart from each other and the spacers ( 13 ) extend perpendicular to the inner and outer walls ( 10 , 12 ).

5. The molding tool ( 1 ) according to claim 4 , wherein between adjacent spacers ( 13 ) and the surfaces of the inner and outer walls ( 10 , 12 ) facing the hollow space ( 11 ), circular through flow openings ( 14 ) are provided for the heating/cooling medium (K).

6. The molding tool ( 1 ) according to claim 5 , wherein the through bores ( 130 ) inside the spacers ( 13 ) taper conically starting from the outer wall ( 12 ) in a direction of the inner wall ( 10 ).

7. The molding tool ( 1 ) according to claim 6 , wherein the through bores ( 130 ) inside the spacers ( 13 ) conically taper from a starting diameter (OD) of approximately 1.5 to 2 mm down to an inner diameter (ID) of 0.3 to 0.5 mm.

8. The molding tool ( 1 ) according to claim 7 , wherein the inner and outer walls ( 10 , 12 ) each has a wall thickness (WT) of 0.3 to 3 mm.

9. The molding tool ( 1 ) according to claim 8 , wherein the hollow space ( 11 ) between the outer wall ( 12 ) and the inner wall ( 10 ) has an inner height (IH) of 3 to 6 mm.

10. The molding tool ( 1 ) according to claim 9 , wherein the spacers ( 13 ) are columnar and have a diameter (SD) of 4 to 6 mm.

11. The molding tool ( 1 ) according to claim 10 , wherein on the outside of the outer wall ( 12 ) facing away from the hollow space ( 11 ), a steam chamber ( 15 ) is formed and communicates with the through bores ( 130 ).

12. The molding tool ( 1 ) according to claim 11 , wherein the steam chamber ( 15 ) has an inner height (HD) of 2 to 4 mm.

13. The molding tool ( 1 ) according to claim 1 , wherein the spacers ( 13 ) function as flow dividers for the heating/cooling medium (K) that can be conveyed through the hollow space ( 11 ).

14. The molding tool ( 1 ) according to claim 1 , wherein the inner and outer walls ( 10 , 12 ) are oriented approximately parallel to each other and spaced a constant distance apart from each other and the spacers ( 13 ) extend perpendicular to the inner and outer walls ( 10 , 12 ).

15. The molding tool ( 1 ) according to claim 1 , wherein between adjacent spacers ( 13 ) and the surfaces of the inner and outer walls ( 10 , 12 ) facing the hollow space ( 11 ), circular through flow openings ( 14 ) are provided for the heating/cooling medium (K).

16. The molding tool ( 1 ) according to claim 1 , wherein the through bores ( 130 ) inside the spacers ( 13 ) taper conically starting from the outer wall ( 12 ) in a direction of the inner wall ( 10 ).

17. The molding tool ( 1 ) according to claim 1 , wherein the inner and outer walls ( 10 , 12 ) each has a wall thickness (WT) of 0.3 to 3 mm.

18. The molding tool ( 1 ) according to claim 1 , wherein the hollow space ( 11 ) between the outer wall ( 12 ) and the inner wall ( 10 ) has an inner height (IH) of 3 to 6 mm.

19. The molding tool ( 1 ) according to claim 1 , wherein the spacers ( 13 ) are columnar and have a diameter (SD) of 4 to 6 mm.

20. The molding tool ( 1 ) according to claim 1 , wherein on the outside of the outer wall ( 12 ) facing away from the hollow space ( 11 ), a steam chamber ( 15 ) is formed and communicates with the through bores ( 130 ).

21. The molding tool ( 1 ) according to claim 1 , wherein the inner wall ( 10 ), the outer wall ( 12 ), and the spacers ( 13 ) are all connected integrally in one piece, formed of the sintered metal.

22. The molding tool ( 1 ) according to claim 1 , wherein the inner wall ( 10 ) is integrally connected to the outer wall ( 12 ) to enclose the hollow space ( 11 ), and the spacers ( 13 ) are integrally connected to and between the inner wall ( 10 ) and the outer wall ( 12 ), extending across the hollow space ( 11 ).

23. The molding tool ( 1 ) according to claim 22 , wherein each of the spacers ( 13 ) includes a tapered through bore ( 130 ) extending through and from the outer wall ( 12 ) toward and through the inner wall ( 10 ).

24. The molding tool ( 1 ) according to claim 1 , wherein the condensate from the inner surface combines with the heating/cooling medium (K) within the hollow space ( 11 ).