Patent ID: 8967933
Filing Date: 2015-03-03
Classification: F16B

Abstract:
1. A fast extraction threaded nut intended to be used on a threaded bolt or male member wherein at least in two of its outer faces comprises notches of variable cross-section wherein the maximum cross-section of the notches is positioned in an outer area and the minimum cross-section is positioned prior to the axial bore wherein the notches allow weakening of the threaded nut or female member only when the threaded bolt or male member is pulled out and the threaded nut is kept intact when the threaded nut is subject to high operational loads and installed in high tonnage, continuous operation machinery, including grinding mills for mineral, such that when compressing said fast extraction threaded nut and said male member with tightening means of common geometry comprising threads or fillet nut means, the notches are formed by a radial depth cut (B) on the outer faces of the threaded nut or female member according to the axial direction along the threaded nut or female member in which the radial depth cut (B) is between 5% to 25% of the nominal diameter of the threaded nut or female member, each of the notches having a width (A), formed by at least two walls, in which the width (A) is between 0.1% to 20% of the nominal diameter of the threaded nut or female member, each of the notches having a bottom end angle (C) which has a sharp projected end, in which the bottom end angle (C) is between 10° to 45° in order to obtain the highest level of stress wherein into each notch are inserted two wedging elements whose angle is between 10° to 35° which are moved in a synchronized manner and facing each other, thus creating a seam and producing an area where the level of stress increases, thereby producing a crack that grows until reaching the inner surface of the central bore.