HISTORY OF THE LOCKING PLIERS
APRIL 8, 1924 LOCKING PLIERS PATENT
Petersen won a patent for the locking pliers in 1924. In 1934, he formed the Petersen Manufacturing Company which opened its first manufacturing plant in 1938.
After the U.S. entered the war, the “Great Arsenal of Democracy” started manufacturing “Liberty Ships”, to transport men and material to allies and the various fighting theaters over the entire world. The ship builders quickly realized that the Petersen locking pliers was the ideal tool to help them build their boats. To save time welders simply welded Petersen’s locking pliers into the hulls rather than taking the time to remove them from the bulkheads they were holding and welding together.
THE CONSTRUCTION OF A LIBERTY SHIP
Thirty-nine years after he died, Petersen’s original concept was finished by engineers who found his conceptional plans in a shoe box and his dream of an automatic locking pliers was finally realized!
Today, the AUTO-GRIP® Locking Pliers, which is the great-great-great grandson of William Petersen’s original locking pliers, is the tradesman’s choice because it combines the convenience of the locking pliers automatically clamping on thick or thin material with the efficiency of no manual adjustment.