## Position and Speed of Electric Motors

Electric motors used in automation systems need some control. We will give you an example of a robot that removes a machined piece and places it on the tray, so that it is possible we will describe its movements:

• leaving an initial position, starting and accelerating;
• when approaching a favorable attack position, decelerate to a stop;
• approaching the part at low speed;
• stop and grab the part;

Start back and accelerate;

The electric motors that are required for this operation must have speed control, for acceleration and deceleration and positioning. They are critical and meticulous controls because if the robot makes a wrong trajectory, with higher speed, it may collide with some accessory or break the part.

The speed and positioning control is done in cycles where the position and the speed of displacement has certain importance for the control of the motor. These electric motors usually already come with sensing coupled to their axis and then receive the designation of “servomotor”.

There are direct and alternating current servo motors.

## Electromagnet Connection – CC

Electric motors of the brakes type are supplied with an initial air gap. In this case the separation between the plateau and the flange is set at the factory in its minimum value. When the brake linings wear out normally, the working air gap gradually increases, and this does not affect the proper functioning of the brake until it reaches the maximum value.

To readjust the air gap to its initial values, we must follow some procedures, as described below:

1) Remove the securing screws of the protective cap;

2) Remove the screws of the protective strap;

where to find ac motors

3) Measure the air gap at three points, close to the stud bolts, with a set of standard blades (spy);

4) If the readings are different from each other, continue adjusting as follows:

– Unscrew the nut securing the flange of the electromagnet, approaching or moving away if necessary, until the recommended initial measurement is reached;

– Tighten the three adjusting nuts equally, leaving the same length on the three springs;

– The size of the air gap must be uniform at the three measurement points, close to the captive screws.