TWO STAGE TORQUE LIMITER

A torque limiting tool (10) is described. The tool comprises a two stage torque limiting mechanism (16) that resides within a housing (18). The torque limiting mechanism comprises a shank (32) positioned through a gear (34), a plate (38), and a bias member (36). The plate is constructed having at least one post (156) and at least one tooth (160) providing a ramp surface (170) that extends outwardly from a plate surface (62). The gear is constructed having at least one throughbore (158), and at least one recess (162) providing at least one inclined surface (192, 194) that resides part-way within the thickness of the gear. The gear and plate are positioned in opposition so that the at least one tooth and extending post are received within or detachably mated to the opposing recess and through-bore. Torque is transferred between the plate and gear when the ramped teeth and extending posts mate with the respective recess and through-bore. A first torque limit is exceeded when the post breaks free from the through-bore. A second, lesser torque limit is exceeded when the ramped teeth release from their mated recess.