Monthly Archives: março 2021

Position and speed of electric motors

Electric motors used in automation systems usually require some control. Note a robot that pulls a machined part from a CNC lathe and places it on the tray of a transport vehicle. Their movements would be: coming out of a known position, starting and accelerating; when approaching a favorable position of attack to the piece, to decelerate until stop; approach the part at low speed; stop and grab the piece; start back and accelerate; decelerate to a favorable position to release the part in the vehicle; release the part.

The electric motors find here vm3538 involved in this movement must have acceleration and deceleration and positioning. They are critical controls because if the robot approaches the part in a wrong trajectory, depending on the approaching speed, it may collide with some accessory or break the part. The same could happen at the time of releasing the piece. In other situations, these controls are decisive for the quality and reliability of the work produced by the machines. For milling a part in a CNC machine, we usually use three electric motors, one for horizontal movements, another for vertical movements and a third for deep movements.

Rotors – Introduction

The proper rotation of electric motors is the basis of many current appliances and sometimes this rotation is evident, as in fans or cakes, but sometimes remains somewhat hidden, as in the washing machine agitators or in the windows electric machines of some automobiles. To understand the operation of the motor we need some basic knowledge about electromagnetism, such as magnets, magnetic forces between magnets, magnetic fields acting on currents. The motor rotor requires a torque to start its rotation. This torque is usually produced by magnetic forces developed between the magnetic rotor poles and those of the stator (fixed part).

Attraction or repulsion forces produced between stator and rotor “pull” enerpac hpt-1500 or “push” the movable rotor poles producing torques, which cause the rotor to rotate rapidly, until the frictions or loads attached to the shaft decrease the resulting torque to the value ‘zero’. After this point, the rotor rotates with a stable angular velocity. Both the rotor and the stator of the motor must be ‘magnetic’ because they are precisely those forces between poles that produce the torque needed to make the rotor rotate.