Patent ID: 6267028
Filing Date: 2001-07-31
Classification: B25B

Abstract:
A one piece, open end wrench head for a fastener having at least two substantially parallel outer engaging surfaces creating an across-width dimension; said open end wrench head having an orifice comprising four principle internal engaging surfaces being arranged about an imaginary central axis with the first and second internal engaging surfaces being positioned on a first jaw and the third and fourth internal engaging surfaces being positioned on a second opposing jaw, said first internal engaging surface being substantially flat and substantially parallel to said imaginary central axis and positioned closer to the open end of said wrench head than said second internal engaging surface, said second internal engaging surface diverging outward from said first internal engaging surface, said third internal engaging surface being substantially flat and substantially parallel to said imaginary central axis and positioned asymmetrically opposing said second internal engaging surface and farther away from the open end of said wrench head than said fourth internal engaging surface, said fourth internal engaging surface asymmetrically opposing said first internal engaging surface and diverging outward from said third internal engaging surface, and, said first and third internal engaging surfaces being spaced apart by a predetermined dimension, said second and fourth internal engaging surfaces being spaced apart by a dimension less than the predetermined dimension by which said first and third internal engaging surfaces are spaced apart, thereby providing for a pinching effect to said fastener under torque.