Electric motor
Electric motor, some of a class of devices that convert electricity to mechanical energy, usually by using electromagnetic phenomena.

What is a power motor?
How can you bring things in motion and keep them moving without moving a muscle mass? While steam engines create mechanical energy using incredibly hot steam or, more specifically, steam pressure, electric motors use electrical energy as their source. For this reason, electrical motors are also called electromechanical transducers.

The counter piece to the electric electric motor is the generator, that includes a similar structure. Generators transform mechanic motion into electric power. The physical basis of both processes may be the electromagnetic induction. In a generator, current can be induced and electricity is created whenever a conductor is at a moving magnetic field. Meanwhile, in an electric engine a current-carrying conductor induces magnetic areas. Their alternating forces of attraction and repulsion generate the foundation for generating motion.
How does a power motor work?
Motor housing with stator
Motor housing with stator
Generally, the heart of an electric motor includes a stator and a rotor. The term “stator” comes from the Latin verb “stare” = “to stand still”. The stator may be the immobile component of a power motor. It really is firmly mounted on the equally immobile casing. The rotor on the contrary is installed to the electric motor shaft and may move (rotate).
In case of AC motors, the stator includes the so-called laminated core, which is wrapped in copper wires. The winding works as a coil and generates a rotating magnetic field when current is flowing through the wires. This magnetic field developed by the stator induces a current in the rotor. This current then generates an electromagnetic field around the rotor. Consequently, the rotor (and the attached engine shaft) rotate to follow the rotating magnetic field of the stator.

The electric electric motor serves to use the created rotary movement to be able to drive a equipment unit (as torque converter and speed variator) or even to directly drive an application as line motor.
What forms of electric motors are available?
All inventions began with the DC motor. Nowadays however, AC motors of varied designs are the mostly used electric motors in the industry. They all possess a common result: The rotary movement of the engine axis. The function of AC motors is based on the electromagnetic operating basic principle of the DC motor.

DC motors
As with most electrical motors, DC motors consist of an immobile part, the stator, and a moving element, the rotor. The stator consists either of a power magnet utilized to induce the magnetic field, or of long lasting magnets that continuously generate a magnetic field. Within the stator is where in fact the rotor can be located, also called armature, that is covered by a coil. If the coil is linked to a way to obtain direct current (a electric battery, accumulator, or DC voltage Ac Induction Motor supply unit), it creates a magnetic field and the ferromagnetic core of the rotor becomes an electromagnet. The rotor is definitely movable mounted via bearings and will rotate to ensure that it aligns with the attracting, i.e. opposing poles of the magnetic field – with the north pole of the armature opposing of the southern pole of the stator, and the other way round.

In order to arranged the rotor in a continuing rotary motion, the magnetic alignment should be reversed over and over. This is achieved by changing the current direction in the coil. The engine has a so-called commutator for this function. Both supply contacts are linked to the commutator and it assumes the duty of polarity reversal. The changing attraction and repulsion forces ensure that the armature/rotor proceeds to rotate.

DC motors are mainly used in applications with low power rankings. These include smaller tools, hoists, elevators or electric vehicles.

Asynchronous AC motors
Instead of immediate current, an AC motor requires three-phase alternating current. In asynchronous motors, the rotor is definitely a so-called squirrel cage rotor. Turning results from electromagnetic induction of the rotor. The stator includes windings (coils) offset by 120° (triangular) for each stage of the three-phase current. When connected to the three-stage current, these coils each build-up a magnetic field which rotates in the rhythm of the temporally offset collection frequency. The electromagnetically induced rotor is definitely carried along by these magnetic fields and rotates. A commutator as with the DC engine is not needed in this way.

Asynchronous motors are also called induction motors, as they function only via the electromagnetically induced voltage. They run asynchronously because the circumferential rate of the electromagnetically induced rotor by no means reaches the rotational quickness of the magnetic field (rotating field). Due to this slip, the effectiveness of asynchronous AC motors is leaner than that of DC motors.

More on the framework of AC motors / asynchronous motors and on what we offer

AC synchronous motors
In synchronous motors, the rotor is equipped with permanent magnets instead of windings or conductor rods. In this way the electromagnetic induction of the rotor could be omitted and the rotor rotates synchronously without slide at the same circumferential swiftness as that of the stator magnetic field. Effectiveness, power density and the possible speeds are thus significantly higher with synchronous motors than with asynchronous motors. However, the look of synchronous motors is also much more complex and time-consuming.

More details about synchronous motors and our portfolio

Linear motors
In addition to the rotating machines that are mainly used on the market, drives for actions on straight or curved tracks are also required. Such movement profiles occur mainly in machine tools and also positioning and managing systems.

Rotating electric motors can also convert their rotary movement into a linear motion using a gear unit, i.e. they can cause it indirectly. Often, however, they don’t have the necessary dynamics to realize especially demanding and fast “translational” movements or positioning.

That’s where linear motors enter into play that generate the translational motion directly (direct drives). Their function could be produced from the rotating electric motors. To do this, imagine a rotating engine “exposed”: The previously circular stator becomes a flat travel distance (track or rail) which can be protected. The magnetic field then forms along this route. In the linear electric motor, the rotor, which corresponds to the rotor in the three-phase motor and rotates in a circle there, is stopped the travel distance in a straight collection or in curves by the longitudinally moving magnetic field of the stator as a so-called carriage or translator.

More details about linear motors and our drive solutions