Self-attaching nut

1. A self-attaching nut for attachment to a panel, comprising:

a body portion including side faces, end faces, a top face and a bottom face;

a central pilot portion projecting from said top face of said body portion including a top face of said central pilot portion and a threaded bore extending through said top face of said pilot portion and through said bottom face of said body portion;

flange portions on opposed sides of said central pilot portion, each of said flange portions having a top face;

parallel grooves on opposed sides of said pilot portion; and

said bottom face of said body portion including parallel projecting rails extending between opposed sides of said threaded bore and said parallel grooves and having coplanar bottom faces, a recess between said rails, and said threaded bore extending through said recess.

2. The self-attaching nut as defined in claim 1 , wherein said recess has a planar bottom face.

3. The self-attaching nut as defined in claim 1 , wherein said parallel projecting rails each have an inclined face extending from said co-planar bottom faces to a bottom face of said recess.

4. The self-attaching nut as defined in claim 1 , wherein said rails are spaced from said threaded bore at least 0.020 inches.

5. The self-attaching nut as defined in claim 1 , wherein said rails are spaced from said threaded bore at least 0.030 inches.

6. The self-attaching nut as defined in claim 1 , wherein said co-planar bottom faces of said rails include parallel grooves extending parallel to said rails spaced from said side faces of said body portion.

7. The self-attaching nut as defined in claim 6 , wherein said parallel grooves in said bottom faces of said rails each include a frangible wire interconnecting adjacent self-attaching nuts.

8. The self-attaching nut as defined in claim 1 , wherein said parallel grooves on opposed sides of said pilot portion are in said top face of said flange portions adjacent said pilot portion.

9. The self-attaching nut as defined in claim 1 , wherein said recess has a depth of between 0.005 to 0.020 measured between said co-planar bottom faces of said rails and a bottom face of said recess.

10. The self-attaching nut as defined in claim 1 , wherein said coplanar bottom faces of said rails extend from generally adjacent said recess to said side faces of said body portion.

11. The self-attaching nut as defined in claim 1 , wherein said coplanar bottom faces of said rails extend a full length of said bottom face of said body portion between said end faces.

12. A rolled self-attaching nut for installation in a panel by a plunger, comprising:

a generally rectangular body portion including parallel side faces, end faces, a top face and a bottom face;

a central pilot portion projecting from said top face of said body portion, including a planar top face of said central pilot portion and a threaded bore extending through said top face of said central pilot portion and said bottom face of said body portion;

parallel flange portions on opposed sides of said central pilot portion, each having a rectangular top face; and

said bottom face of said body portion including parallel projecting rails on opposed sides of said threaded bore having coplanar bottom faces spaced from said threaded bore, a channeled recess between said rails and said threaded bore extending through said recess, wherein a plunger is driven against said coplanar bottom faces of said rails during installation of said self-attaching nut in a panel.

13. The rolled self-attaching nut as defined in claim 12 , wherein said coplanar bottom faces of said rails extend a full length of said bottom face of said body portion between said end faces.

14. The rolled self-attaching nut as defined in claim 12 , wherein said parallel projecting rails each include an inclined face extending inwardly from said coplanar bottom faces to a bottom face of said recess.

15. The rolled metal self-attaching nut as defined in claim 12 , wherein said rails are spaced from said threaded bore at least 0.020 inches.

16. The rolled metal self-attaching nut as defined in claim 12 , wherein said coplanar bottom faces of said rails each include parallel grooves extending parallel to said rails generally in a midportion of said rails.

17. The rolled metal self-attaching nut as defined in claim 16 , wherein said parallel grooves in said bottom faces of said rails each include a frangible wire interconnecting adjacent self-attaching nuts.

18. A self-attaching nut for attachment to a panel, comprising:

a generally rectangular body portion including parallel side faces, end faces, a top face and a bottom face;

a central pilot portion projecting from said top face of said body portion including a planar rectangular top face of said central pilot portion and a threaded bore extending through said top face of said pilot portion and said bottom face of said body portion;

flange portions on opposed sides of said pilot portion each having a top face; and

said bottom face of said body portion including parallel projecting rails on opposed sides of said threaded bore spaced from said threaded bore having coplanar bottom faces, a recess between said rails having a bottom face with said threaded bore extending through said bottom face of said recess, and said top face of said pilot portion and said coplanar bottom faces of said rails each including a groove extending parallel to said parallel projecting rails.

19. The self-attaching nut as defined in claim 18 , wherein each of said parallel grooves in said co-planar bottom faces of said rails include a frangible wire interconnecting adjacent self-attaching nuts.

20. The self-attaching nut as defined in claim 18 , wherein said parallel projecting rails each have an inclined face extending inwardly from said coplanar bottom faces of said rails to said bottom face of said recess.