Effect of lateral oscillations of a conveyer bed on the tension in the traction unit

Abstract

During operation of a main conveyer with movable or stationary support rollers, for various reasons oscillations arise and are sustained for a long time in the traction-carriage unit. The intensity of these vibrations depends to a great extent on the initial tractive force, and in some cases they become so marked that there is a real danger that they may break the support structure of the conveyer. The traction-carriage unit executes transverse vibrations relative to its equilibrium position, which is that of free hanging between the supports under the distributed load. Its longitudinal compliancy is characterized by elastic deformation and changes in the sag. The spacing of the track rollers of the load-carrying bed is determined by the tensile force of the traction unit. But the initial length of the bed in the span between the movable rollers remains unaltered. In conveyers with stationary supports the initial length of the traction unit in the span does not remain constant; according to the magnitude of the tension, it can be increased at the expense of neighboring sections, or decreased with transfer of part of it to the adjacent span. In transverse vibrations of the bed,an important part is played by themore » critical tension in the traction unit. Under the influence of this force the traction unit acquires an elongation such that its initial length in the span is equal to the distance between rollers. Both on stationary and on movable supports, in this case the bed sags only owing to elongation of the tractive unit. If the tensioning force is greater than the critical value, then the initial length of the bed in the span is less than the spacing between rollers. If the tension is less than the critical value, the length of the bed is greater than the distancebetween supports.« less