Polygonal driving means with inbuilt collar
It has become apparent that the dimensions of inbuilt-collar driving means of the same nominal size may vary according to the method of manufacture. The dimensions of the collar must therefore be adapted to suit the mode of manufacture, at the expense of its strength or mass. Moreover, the transmissible torque for tightening and loosening operations varies according to a useful wrenching height. In order to have a useful height identical to the height of the shank, the idea underlying the invention involves pushing the frustoconical collar of a driving means in towards its center along the extension of the sides of the shank. The inbuilt-collar driving means of the invention is suited to all modes of manufacture, and can be manufactured without adversely affecting the dimensions of the driving means or its installation.
1. A monolithic nut comprising a polygonal shank with lateral sides and an inner wall on the polygonal shank having cylindrical threads along the inner wall of the polygonal shank, the monolithic nut having a frustoconical collar having a flat bottom surface wherein the threads and the bottom surface are configured such that a threading movement of the nut along a mating threaded surface puts the bottom surface into contact with a surface facing the bottom surface of the collar, such that the contact places an axial load on the bottom surface of the collar, an upper-most collar surface opposite the bottom surface and a frustoconical curved surface between the bottom surface and the upper-most collar surface, wherein the frustoconical collar comprises a plurality of socket faces hollowed out from and relative to the frustoconical curved surface in an area between the bottom surface and the upper-most collar surface and wherein the socket faces extend to a plane defined by the respective polygonal shank lateral side, each lateral side of the polygonal shank being aligned with a respective hollowed-out socket face, and each lateral side of the polygonal shank terminates at a substantially transverse surface between the lateral side and a respective hollowed-out socket face at the intersection of the upper-most collar surface and the polygonal shank.
2. The nut of claim 1 wherein the socket faces are planar or concave.
3. The nut of claim 1 wherein the nut is obtained by forging via a die, machining, casting, sintering or plastic injection molding.
4. The nut of claim 1 , wherein the shank is hexagonal or bi-hexagonal.
5. The nut of claim 1 , further comprising fillets fitted between the socket faces of the frustoconical collar and the lateral sides of the polygonal shank.
6. The nut of claim 1 wherein the nut is made out of titanium alloy, stainless steel, nickel alloy or aluminium alloy.
7. The nut of claim 4 , wherein the frustoconical curved surface of the frustoconical collar forms an angle of at least forty-five degrees with a circular base of the collar.
8. The nut of claim 1 , wherein the socket faces are marked or colored.
9. The nut of claim 1 , wherein the socket faces form respective concave surfaces in the frustoconical curved surface.