Screw connecting electrical conductors with a shearable screw

1. A shearable screw for connecting electrical leads, comprising:

a shearable screw body with a longitudinal axis; and

a threaded section on said screw body threadable into a bore of a terminal body for retaining electrical leads, said threaded section having an asymmetrical thread profile and including a buttress thread, said thread profile having first and second roundings radially on an outside thereof between first and second flanks of said thread profile and a planar section between said first and second roundings.

2. A shearable screw according to claim 1 wherein

said first flank is a pressure loaded flank when threaded in the terminal body;

said pressure loaded flank and said longitudinal axis enclose a pressure flank angle of greater than 60 degrees and less than 87 degrees.

3. A shearable screw according to claim 2 wherein

said pressure flank angle is greater than 70 degrees and less than 87 degrees.

4. A shearable screw according to claim 3 wherein

said pressure flank is greater than 80 degrees and less than 87 degrees.

5. A shearable screw according to claim 1 wherein

said first and second flanks enclose a flank angle of greater than 30 degrees and less than 60 degrees.

6. A shearable screw according to claim 5 wherein

said flank angle is greater than 40 degrees and less than 55 degrees.

7. A shearable screw according to claim 6 wherein

said flank angle is greater than 45 degrees and less than 55 degrees.

8. A system, comprising

a terminal body having an internally threaded terminal bore and being configured to and capable of receiving electrical conductors therein;

a shearable screw having a threaded region extending between opposite first and second ends of said screw in a longitudinal direction thereof, said threaded region including an outer thread over at least a portion of an axial extent thereof threadable in said terminal bore to secure the electrical conductors in said terminal body, said screw including a screw bore opening toward said first end;

a thrust element being insertable and introduced into said screw bore in a region between a support in said screw bore and said first end of a said screw bore, and applying a compression force applied on said shearable screw at said support by threading said thrust element to a thread of a fastener of said shearable screw, while simultaneously applying a tensile force in said shearable screw in a region of said thread of said fastener causing a shearing; and

a coating on said shearable screw improving frictional characteristics thereof between said thrust element and said shearable screw.

9. A system according to claim 8 wherein

said coating comprises at least one of zinc lamellas or aluminum lamellas.

10. A system according to claim 8 wherein

said shearable screw has a longitudinal axis; and

said threaded region is threadable into said bore of a terminal body for retaining the electrical conductors, said threaded section having an asymmetrical thread profile and including a buttress thread, said thread profile having first and second roundings radially on an outside thereof between first and second flanks of said thread profile and a planar section between said first and second roundings.

11. A device for connecting electrical conductors, comprising:

a terminal body having at least one internally threaded bore;

a shearable screw for connecting electrical leads in said terminal body;

a shearable screw body with a longitudinal axis; and

a threaded section on said screw body threadable into said bore of said terminal body for retaining the electrical leads, said threaded section having an asymmetrical thread profile and including a buttress thread, said thread profile having first and second roundings radially on an outside thereof between first and second flanks of said thread profile and a planar section between said first and second roundings.

12. A device according to claim 11 wherein

said terminal body is formed of aluminum having a copper content of more than 0.1 percent.

13. A device according to claim 12 wherein

said copper content is more than 0.2 percent.

14. A device according to claim 13 wherein

said copper content is more than 0.4 percent.

15. A device according to claim 11 wherein

a lubricant is between said terminal body and said shearable screw, said lubricant including a solid lubricant mixed with a mineral oil.

16. A device according to claim 11 wherein

said terminal body comprises at least one opening receiving and clamping an electrical conductor therein; and

a hollow centering sleeve being received in said opening and having an inner diameter matched to an outer diameter of said electrical conductor.

17. A device according to claim 11 wherein

said terminal body comprises at least one opening receiving and clamping an electrical conductor therein; and

a plurality of hollow centering sleeves having different inner diameters are integrally arranged on a holding strip being receivable in said opening, at least one of said inner diameters matching an outer diameter of said electrical conductor.

18. A device according to claim 11 wherein

an opening is in said terminal body outside of said shearable screw after being threaded in said terminal body; and

a cover covers and is clampingly fixed in at least one of said opening in said terminal body or an opening of said shearable screw.

19. A device according to claim 18 wherein

additional covers are integrally arranged together on a holding strip.