Improvement of magnetic system of the speed sensor in the devices of the impact parameters control

摘要

In this paper the task of optimization of the magnetic system velocity sensor devices for controlling the parameters of impact and machinery percussion is solved. The most widespread optimization criteria are the following: weight, size, and cost on a temporary basis, which respectively correspond to minimum response time, minimum winding time constant, maximum operational reliability, energy performance according to the maximum kinetic energy of the working body, maximum induced EMF in the coil, maximum traction, minimum energy consumption, and maximum efficiency. The reasoning of choosing optimality maximum sensitivity of the sensor, as well as minimum mass of active material as criteria is connected with using induction sensors for detecting impact energy at the impaction moment. The graph of the demagnetization-vs-return-line curve is presented. The position of the operating point of permanent magnet is determined by the intersection of the beam corresponding to the relative conductivity of the air gap and the return lines. The analytical solution for the flux measurement coil speed sensor, the electromotive force in the coil by opening the magnetic circuit, as well as the sensitivity of the inductive speed sensor are given in the paper. It is shown that the sensitivity of the sensor depends on the working gap, while the gap enlarging leads to its desensitization increase.