Looseness detecting method of screw tightening part

Abstract

Abstract PURPOSE: To detect the looseness at the screw tightening part from the position of the inflection point of the characteristic curve between the relative rotational angle and the tightening torque in case the screw tightening is increased. CONSTITUTION: The tightening is increased to the screw 1 by means of the torque wrench 2 possessing the rotational angle detector 3 and the torque detector 4, and the characteristic curve at that moment is obtained. With the characteristic curve in which the rotational angle Ψ and the torque T are set as the horizontal and vertical axes respectively, no looseness of the screw is decided if a coincidence is obtained between the torque point (a) from the initial tightening Ψ a and the point (d) where the nut starts rotation (curve A). And some looseness of the screw is decided in case the point (d) is lower than the point (a) (curve B). COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Masaaki Kikuchi
• 👤 Atsuro Itagaki
• 👤 Tamotsu Sato

Bibliographic Details