Fastener having recess useable with multiple drivers and method of manufacture
A fastener is described having a head formed with a recess which accommodates a square head driver, symmetrical drivers, such as PHILLIPS™ style drivers, asymmetrical style cross head drivers, such as POZIDRIV® style drivers, and combination square and cross drivers without compromising performance of the drivers.
1. A method of forming a recess in the head of a fastener comprising the steps of:
forming a cross slotted recess portion into said fastener head extending a first depth from a top and a bottom, and having an overall cross slot geometry, said slots being formed by opposing walls, wherein said opposing walls converge symmetrically, from said top to said bottom, at a symmetrically formed included angle having an overall size that is substantially equivalent to an included angle of an asymmetrical cruciform fastener manufactured in conformity with the standard for type Ia fasteners, and
forming a square recess portion into said fastener head extending a second depth from said top, and having an overall square geometry, wherein said second depth is less than said first depth, whereby said overall square geometry is within said overall cross slot geometry.
2. A method of forming a recess in the head of a fastener, as described in claim 1 , wherein said included angle is 2.5 degrees.
3. A method of forming a recess in the head of a fastener, as described in claim 1 , wherein said opposing walls are each inclined at an angle of 1.25 degrees to the vertical to cause said convergence.