METHOD OF DETERMINING DYNAMIC COEFFICIENT OF EXTERNAL FRICTION BETWEEN TWO MOVING SAMPLES Russian patent published in 2015 - IPC G01N19/02 

FIELD: testing technology.

SUBSTANCE: lower sample is tilted relative to the horizontal with a certain angle φ, the upper sample is mounted on the working surface of the lower, is held by the hinge connection having the ability of free rotation relative to the suspension point in a plane parallel to the surface of the lower sample, relative movement of the samples in the horizontal direction is arranged, the angle α of turning of hinge connection, established in it, is measured, and the dynamic external coefficient of friction is determined by the formula $$m=\frac{tg\phi }{tg\alpha }.$$ The lower sample is made in the form of a disk driven to rotation about an axis perpendicular to its flat working surface. By moving the suspension point of hinge connection or changing its length, the upper sample is brought in a position where the gravitational vector passing through its centre of mass crosses the line of the greatest slope on the surface of the lower sample, passing through the axis of its rotation.

EFFECT: possibility of continuous and accurate determining of the dynamic coefficient of external friction, as well as evaluation of its variation in change of speed of relative movement of the samples, with the measurement of only the geometric parameters of the system, without determining the friction force.

2 cl, 2 dwg