SU634209A1 - Rpm transmitter - Google Patents

Description

(54) BPAilEHHH SPEED SENSOR

The invention is relative. Measure the power equipment and can be used for non-contact measurement of the speed of Erasche 1 and from near-normal values to the maximum under harsh operating conditions.

Induction speed sensors are known that have contained a permanent magnet or magnetic circuit with a signal coil wound around it, in which an electromotive force (EMF) is induced when passing through a ferromagnetic insert or tooth of a ferromagnetic wheel; In the outer homogeneous fields, the second coil is usually applied opposite the signal,

The closest in technical essence to the proposed m. Is a speed sensor of a vishni, which has a gear wheel made of ferromagnetic material, a magnet, the first system formed by a ferromagnetic core and winding - and a second system identical to its characteristics formed also by the core and winding 2J . The windings are connected to each other in a counter so that if

is in a uniform external field, identical windings are induced in the 3 windings,. and the voltage at the output of the sensor will be zero.

 this sensor cannot detect near-circumference values of rotational speed 5, because of the emf, cavodi; and in the winding, the right of the gyroporoneal rate of change of the magnetic dip, and the CPsPs turns, i.e.

af

dt

EMF induced in the winding e ke;

F dt

rate of change of flux;

4V number of turns.

If speed

change magnetic lf

approaching zero then

The hfED, induced in the winding, becomes commensurate with the level of interference. Therefore, in order to extend the measurement range in the direction of small values of the rotational speeds in the sensor, the number of turns W or the size of the magnet and the magnetic core increases, which increases the overall dimensions of the sensor,

The purpose of the invention is to expand the measurement range.