Mathematical Model of the Dynamic Process in the System "Brake Disc - Rotating Brake Cabin"
A mathematical model of the dynamic processes occurring in the area of mutual contact of the working elements of the disc brake of railway vehicles has been developed. The mathematical model is based on the equations of velocities, forces and moments of relative motion of the working elements of the disk brake. The mathematical model includes: the components of the linear velocity vectors of the elements of the contact surface of the brake disc and the brake pad; components of relative velocity vectors of the elements of the contact surface of the brake disc and brake shoe; components and moments of frictional forces applied to the brake disc and the brake shoe. Disc brakes with friction elements "brake disk - fixed brake shoe" and "brake disk - rotating brake shoe" are considered, realizing, respectively, a simple and complex relative motion of the contact of the working elements of the disk brake. The adequacy of the obtained mathematical model is estimated by comparing the results of mathematical modeling with the results of bench tests carried out on a full-scale bench installation based on an asynchronous traction motor, a car gear box and a tram brake disc. The results of a comparative analysis of disc brakes realizing a simple and complex relative motion in the process of contact of working elements are given. It is established that disc brake with rotating brake pads has a less deforming and distorting effect on the construction of the tick mechanism, as a result of which a better uniformity in the distribution of the pressing force over the surface of the rotating shoe is achieved than in the case of a stationary brake shoe. The disc brake with rotating brake pads has a better distribution of energy release and wear compared to the disc brake standard design, which determines the practical value of the developed mathematical model and the results of modeling and experiments.