Three-point fastener
Fasteners are disclosed for reducing mass of the fastener, while being configured for use with standard torque delivery tools. The fasteners include non-torque bearing surfaces disposed between torque bearing surfaces.
1. A fastener comprising:
a threaded portion; and
a bearing portion, wherein the bearing portion comprises:
exactly three bearing surfaces designed to receive torque from a tool and transmit torque to the threaded portion, wherein each bearing surface includes two adjacent sides with an edge disposed therebetween, the two adjacent sides forming an angle of approximately 120 degrees therebetween; and
three non-bearing surfaces, wherein each of the three non-bearing surfaces has a convex curve;
wherein each non-bearing surface is disposed between a respective two of the exactly three bearing surfaces, and
wherein for each of the exactly three bearing surfaces, each side of the two adjacent sides is substantially planar and directly extends from an associated edge disposed between the two adjacent sides to one of the convex curves without forming any corners.
2. The fastener of claim 1 , wherein the bearing surfaces are configured to receive torque from a standard socket tool and transfer torque to the threaded portion.
3. The fastener of claim 1 , wherein each edge of the bearing surface is disposed opposite one of the non-bearing surfaces.
4. The fastener of claim 1 , wherein the adjacent sides of each bearing surface are symmetrically disposed about the edge of the bearing surface.
5. The fastener of claim 1 , wherein one of the sides of each bearing surface is parallel to only one other side of one other bearing surface.
6. The fastener of claim 5 , wherein a distance between the parallel sides of the bearing surfaces is defined by a dimension determined by an industry standard.
7. The fastener of claim 1 , wherein the sides of each bearing surface are flat.
8. The fastener of claim 1 , wherein the edges of the bearing surfaces are equally spaced around a longitudinal axis of the fastener.
9. The fastener of claim 1 , wherein each edge of the bearing surfaces are spaced 120 degrees from each other edge of the bearing surfaces.
10. The fastener of claim 1 , wherein each edge of the bearing surface is disposed in the middle of each bearing surface.
11. The fastener of claim 1 , wherein the threaded portion comprises internal threads.
12. The fastener of claim 1 , wherein the threaded portion comprises external threads.
13. The fastener of claim 1 , further comprising a cap disposed about the bearing portion, wherein the cap comprises:
three cap bearing surfaces designed to receive torque from a tool and transmit torque to the threaded portion, wherein each cap bearing surface includes two adjacent cap sides with a cap edge disposed therebetween; and
three cap non-bearing surfaces;
wherein a cap non-bearing surface is disposed between each of the cap bearing surfaces,
wherein each of the cap bearing surfaces overlies one of the bearing surfaces, and
wherein each of the cap non-bearing surfaces overlies one of the non-bearing surfaces.
14. The fastener of claim 13 , wherein the fastener comprises a flange portion, the cap being pressed around the flange portion to retain the cap onto the bearing portion without welding the cap.
15. The fastener of claim 1 , wherein the fastener comprises approximately 11 percent less mass than a standard fastener sized for the same application.