Nauka i Obrazovanie (Jan 2017)
Calculation of Stress and Strain on Outer Shell of Roller One-Way Clutches
Abstract
The increased load capacity and durability of the one-way clutches with simultaneous reduction of mass-dimensional characteristics is largely governed by improving the calculation procedures of the stress-strain state of their basic elements.Best operating practices of roller one-way clutches in drive machines show that the outer shell is one of the most loaded elements that has an impact on the working capacity of clutches as a whole.Although, when working in the drive machine, the outer shell destruction may occur quite often, its stress-strain state is, usually, calculated by the approximate and simplified formulas to calculate the rings of the simple shape with the uniform stress distribution over the cross-sections.To study and define the impact nature of the geometrical parameters of the outer shell on its arising stress and strain, solid-state computer simulation and calculation has been performed in the national T-FLEX CAD software complex by the finite element method. The article proposes to use the influence coefficients to estimate an extent of the impact of different geometrical parameters.During the computational experiment, the geometric parameters were varied in ranges corresponding to the main dimension types of the clutches used in drive machines: the inner diameter of the shell – =40-240 мм; the number of block rollers - =3-5; the relative thickness of the shell – =0,06-0,14; the relative thickness of the plate – =0,04-0,12; relative to the length of the shell =0,20-0,50.It has been found that with changing shell thickness the values of arising stresses and strains decrease, respectively, 2.05 and 2.19 times more than with changing plate thickness.Processing of results of computational experiments allowed us to obtain the empirical formulas to calculate a stress-strain state in any combination and in a wide range of changing geometrical parameters of the outer shell.The proposed procedure allows us to raise the reliability and computational accuracy of the stress-strain state of the outer shell of the one-way clutches.
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