The Specifications of Phillips Screws
- In the early 1930s when original slot screws became too weak or difficult to turn in some manufacturing applications, the cruciform design was created by J.P. Thompson. Though Thompson received the patent in 1933, it took more than a year of trying to convince people that his new design was feasible to produce. Eventually an engineer named Henry Phillips was convinced of the superiority of Thompson's design. In 1934 he purchased the patent. Today the Phillips Screw Company owns the rights to more than 10 unique screw designs used the world over in industrial and military and aerospace applications.
- Phillips' Pozidriv screw design is a modification of the traditional Phillips cruciform design. It is an industrial, self-centering screw with recessed edges that helps to reduce operator fatigue. According to Phillips, the Pozidriv screw provides greater driving surface and reduces "fall away" -- the erosion or stripping of the screw's edges.
- Phillips' Tri-wing screw was designed for aerospace applications. The Tri-wing was designed to allow easier driving and removal of screws. The unique shape of the screw head was designed to prevent tampering and removal by anyone not possessing the unique Tri-wing screwdriver.
History
Pozidriv
Tri-Wing
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