Step engines are most common in digital control schemes, technological process control circuits and machines. They are electromechanical devices that convert electrical impulses into discrete mechanical movements. As electric pulses come from the engine, the rotor rotates with discrete steps. The speed of rotation is directly proportional to the frequency at which impulses are accepted.
The step engine is popular in digital control schemes, such as robotics, because it is well suited for taking digital impulses for stepped regulation. Each step causes a certain amount of degrees to turn the shaft. The rotation of the output shaft caused by each pulse is measured in degrees.
Since walking engines can be excited by square waves, they are easily controlled using inexpensive digital schemes. Nevertheless, through the use of power modulation methods for converting quadrature square waves into sinuses and mowers virtually infinite resolution, a step is possible. This is called “micro-drocaming”, where each separate change in levels of the sinus and cosine is one micro-shag.
Advantages:
Accurate and repeated positioning. Quick Start / Stop. No brushes or switch. The possibility of a very low rotation speed.
Flaws:
Not easy to work at high speeds. Resonances may occur if it is not controlled properly.
There are three main types of step engines:
1. With variable resistance (VR)
Steping engines with variable resistance do not use a rotor with constant magnets. Instead, the rotor is made of black material, which is trying to align himself with an applied magnetic field (just like a nail or iron sawdust will rotate in order to leve himself with magnetic lines). Variable resistance engines are used for the area with a relatively low torque and much less often than hybrid step engines described below.
2. Permanent Magnet (PM)
Stepmane engines with a permanent magnet use a rotor with constant magnets. The rotor usually has two poles that join the appropriate poles that are energized at the stature. These engines are relatively inexpensive, but, as a rule, have large sizes than hybrid step engines.
3. Hybrid (HB)
Step engine
Hybrid step engines combine the best characteristics of step engines with alternating resistance and engines with constant magnets. They are built with several gear poles of the stator and a rotor with constant magnets with several teeth at each pole. Hybrid engines have teeth on the rotor, which are slightly resolved with teeth at the stature at successive positions of the poles. When the voltage is supplied to one position on the status, the rotor rotates one step to level the teeth in this position. The next pole at the stature makes the rotor rotate an additional step to level the teeth in a new position. This method allows you to take more steps than the number of poles on the stature.
A hybrid step engine
Standard hybrid engines have 200 rotor teeth and rotate with an angle of 1, 8 degrees (2 phases), 0, 9 degrees (3 phases), or 0, 72 degrees (5 phases). Since they have a high static and dynamic moment and can work at very high step speeds, hybrid step engines are used in a wide variety of industrial areas.
Manufacturers: Advanced Micro Systems, Astrosyn, Continental, Electrocraft, Hansen, Haydon, JVL, Kollmorgen, Micromo, Mitsumi, Parker, NMB, NPM, Phytron, Portescap, Rebek, Sanyo Desenki Saehan, shinano Kenshi
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