Disc for an agricultural implement
The invention refers to a disc ( 8 ) for an agricultural implement ( 1 ) comprising an annular, outside a predetermined center diameter (D) defined, soil-cultivating portion ( 44 ), a central, inside a predetermined center diameter (d) defined, dish-shaped portion ( 43 ), with a boss-receiving, inner side and between these portions an existing, annular connection portion ( 45 ) with fastening screw holes ( 46 ). The connection portion ( 45 ) is a truncated conical portion, the inner mantle surface of which is mainly straight or double-bowed with the convex side facing said inner side and a line through the opening plane in the hole opening of each fastening screw hole on said inner side forms an angle α with a plane that is perpendicular to the center line of the disc, wherein the angle α is 5°-10°.
1. Disc for an agricultural implement comprising an annular, outside a predetermined centre diameter (D) defined, soil-cultivating portion, a central, inside a predetermined centre diameter (d) defined, dish-shaped portion, with a boss-receiving, inner side and between these portions an existing, a connection portion with fastening screw holes, which are designed to accept fastening screws parallel with a disc centre line of said disc and parallel to each fastening screw, wherein said connection portion is a truncated conical portion and that a line parallelly through the opening plane in the hole opening of each fastening screw hole on said inner side forms an angle (α) with a plane that is perpendicular to the disc centre line, wherein said angle (α) is 5°-10°, and
whereby transitions between said soil-cultivating portion and said connection portion and between said connection portion and said central dish-shaped portion are arranged without edges and are comprised of obtuse external angles,
each fastening screw hole in the connection portion of the disc has a sunken part,
the truncated conical portion has an angled opening relative to the sunken part to accept a head of each fastening screw,
said angled opening is flush with an outer surface of the truncated conical portion,
the truncated conical portion has a surface,
the connection portion is angled inward towards the dish-shaped portion by said angle (α) where an inner surface of the truncated conical portion abuts against a boss, and
an outer end surface of the dish-shaped portion forms an additional angle (β) in relation to the surface of the truncated conical portion.
2. Disc according to claim 1 , wherein said angle (α) is 6°-8°, preferably 7°.
3. Disc according to claim 1 , wherein each fastening screw hole in the connection portion of the disc has the sunken part and a mainly circular cylindrical part and that the interface between these parts lies within the periphery of the disc.
4. Disc according to claim 1 , wherein said line through the opening plane on the inner side of the disc forms the additional angle (β) with a mainly planar end section of said dish-shaped portion, wherein said additional angle (β) is 130°-140°.
5. Disc according to claim 4 , wherein said additional angle (β) is 132°-135°, preferably 133°.
6. Disc according to claim 1 , wherein the transitions between said soil cultivating portion and said connection portion and also between the connection portion and said dish-shaped portion are bowed and have a radius.
7. Disc according to claim 1 , wherein the disc has a mainly similar thickness along its entire extension.
8. Disc aggregate comprising a tool arm with the boss, which is adapted to shape-constrainedly accept a disc according to claim 1 .
9. Agricultural implement with a predetermined number of disc aggregates, which each comprise a tool arm with the boss, which is adapted to shape-constrainedly accept a disc according to claim 1 .
10. Disc according to claim 2 , wherein each fastening screw hole in the connection portion of the disc has the sunken part and a mainly circular cylindrical part and that the interface between these parts lies within the periphery of the disc.
11. Disc according to claim 2 , wherein said line through the opening plane on the inner side of the disc forms the additional angle (β) with a mainly planar end section of said dish-shaped portion, wherein said additional angle (β) is 130°-140°.
12. Disc according to claim 3 , wherein said line through the opening plane on the inner side of the disc forms the additional angle (β) with a mainly planar end section of said dish-shaped portion, wherein said additional angle (β) is 130°-140°.
13. Disc according to claim 2 , wherein the transitions between said soil cultivating portion and said connection portion and also between the connection portion and said dish-shaped portion are bowed and have a radius.
14. Disc according to claim 3 , wherein the transitions between said soil cultivating portion and said connection portion and also between the connection portion and said dish-shaped portion are bowed and have a radius.
15. Disc according to claim 4 , wherein the transitions between said soil cultivating portion and said connection portion and also between the connection portion and said dish-shaped portion are bowed and have a radius.
16. Disc according to claim 5 , wherein the transitions between said soil cultivating portion and said connection portion and also between the connection portion and said dish-shaped portion are bowed and have a radius.
17. Disc according to claim 2 , wherein the disc has a mainly similar thickness along its entire extension.
18. Disc according to claim 3 , wherein the disc has a mainly similar thickness along its entire extension.
19. Disc according to claim 4 , wherein the disc has a mainly similar thickness along its entire extension.
20. Disc according to claim 5 , wherein the disc has a mainly similar thickness along its entire extension.