Study Of Logarithmic Spiral Surface Wedge Block Backstopdesignparameters

The Backstop is mainly installed in the high-speed reducer shaft or intermediate shaft,which role is to quickly and effectively prevent abnormal operation of the device,avoid the accidents and ensure the safety of equipment and personnel.The Backstop with wedge of eccentric-arc profile is the most common one of them.Aiming at the shortcoming of the current non-contact backstop with wedge of eccentric-arc profile,based on logarithmic spiral which has the fixed Angle characteristics.Non-contact work of the Backstop with wedge of logarithmic spiral profile,which outstanding advantage is the wedge force is more uniform,the wear degree of wedge is relatively uniform,non-return process is more stable,higher safety,longer service life.Therefore,non-contact work of the Backstop with wedge of logarithmic spiral has a great application prospect,but for its design parameters is still blank.This paper studies initial diameter and coefficient to the stress conditions of the wedges in the Backstop process of the backstop.Firstly,select a set of logarithmic spiral line design parameters.The model of non-contact work of the Backstop with wedge of logarithmic spiral profile is built by Solid Works.After the completion of the modeling,Verify effection of the design parameters(initial diameter and coefficient of involute)to meet the wedge realize backstop work conditions and the wedge Block to generate a non-contacting running conditions and analysis the non-contact working process of kinematics.Secondly, the stress conditions at different times can be gained through dynamic simulation of backstop process of the Backstop applied by ANSYS/LS-DYNA.It is concluded that the shape of the inner side of the wedge Block is smaller stress than that of the outer surface in backstop process of the Backstop.Finally, the design parameters of Logarithmic Spiral of the inner side of the wedge are studied.It is found that the contact stress of the wedge decreases with the increase of the initial diameter of Logarithmic Spiral of the inner side of the wedge when the involute coefficience of the Logarithmic Spira is constant,and the contact stress of the wedge decreases with the increase of theinvolute coefficience of Logarithmic Spiral of the inner side of the wedge when the initial diameter of the Logarithmic Spira is constant.The research has an important reference value for the development of non-contact Backstop with wedge logarithmic spiral profile.