The Origin of Torque
The word "torque" generally means the "twisting or turning moment" and is widely used as an engineering term. However, torque originally referred to a type of necklace worn in ancient times. The Celts who fought against the Roman Empire wore a kind of twisted jewelry around their necks as symbol of being a nobleman and as a good luck charm. The name "torque" was given by the Romans who in Latin described these Celtic necklaces as "torquere" or twisted. The spiral pattern was a sacred symbol of the soul for the Celtic people and came to represent the enemies of Rome.
In recent times, torque is no longer thought of as a twisted piece of jewelery but rather refers to the amount of tightening for bolts and screws. The purpose is no longer that of a good luck symbol for battle, but torque still carries with it the charms of safety and power.
~Mayaumi Tsurouko, Professor at Ritsumeikan University
Translated from original Japanese text
Birth of Japan's First Torque Wrench
In May 1949, Tohnichi Manufacturing was established through a partnership between Shu Tsuji, who had led the technical team at the Hitachi Aircraft Company and Shigetaka Nanbu of Tokyo Koki Seizosho Ltd. Tohnichi developed Japan's first torque wrench in 1951 a major development for the new company. In 1956, Tohnichi developed a torque wrench that used a toggle mechanism (QL), followed by a torque screwdriver ( LTD) and a torque meter (OT) in 1957.
For Tohnichi which started out as a subcontractor of Hitachi, the development of its own original products was a major accomplishment since its founding. Around this time the use of impact wrenches by automobile manufacturers was common and many difficulties had to be overcome for the introduction and adoption of the use of torque wrenches. The advantages of Tohnichi's torque products including torque accuracy and durability were recognized confirming Tohnichi's course towards expanding its torque product offerings.