Gear motors
- the ingenious combination of motors and gearboxes
The gear motors combine a motor and at least one
gearbox to form a fixed assembly. This assembly usually has a common article
number and can be viewed as one product. In the case of gear motors with an
electric motor, the assembly often includes a rotary or incremental encoder
that is mounted at the end of the electric motor. We are primarily looking at
the gear motors, which are coupled with an electric motor. This is also the
main part of the gear motors.
In exceptional cases, there are also internal
combustion engines that are designed as gear motors. These can be found in
aircraft construction and in compact drives for the motorcycle industry.
The gear
motor and the physics
The physics of the electric motor has been dealt
with in detail in the electric motors category. The gearbox connected to the
electric motor subsequently changes the speed of the armature shaft towards the
output of the gearbox. As a rule, the speed change is slow. This increases the
output torque of the geared motor at each gear stage. Each gear stage has an
efficiency of approx. 98%.
Gear motors with spur or bevel gears can also be
operated as a generator, i.e. mechanical movement can be converted into
electrical energy. This does not work with geared motors with a worm gear. Worm
gear sets are self-locking.
The gear
motors, its types, sizes and designs
Gear motors are available in different types and
designs. A distinguishing feature is the type of motor, alternating current
electric motor (AC motor) or direct current motor (DC motor).
In addition to the motors, geared motors also
differ from one another in their design. We know the following types of gear
motors:
· Flat gear motors, input and output axes are offset parallel to each other
· Planetary gear motors, input and output axes are coaxial with each other
· Bevel gear motors, input and output axes have an angular offset of 90°
· Worm gear motors, input and output axes have an angular offset of 90°
Of course, the gearbox itself also exists without
an electric motor being installed. Then one speaks only of a gearbox instead of
a gear motor. These gears can then be connected to a motor in the construction
by means of a coupling to form a "gear motor unit".
As with electric motors, gear motors are also
available in a wide variety of designs. Two of the best-known variants are the
flange gear motor and the foot gear motor. There is also a combination in which
the gear unit has a foot and an additional flange on the output shaft. The
electric motor is usually attached to the gearbox as a flange motor.
Another distinguishing feature is the hollow shaft
or the output shaft (pin) at the output of the gearbox. On request, a gearbox
can also be designed with an output shaft on both sides.
Many manufacturers also offer electric motors
directly as individual motors. This is why you will find electric motors as a
separate category on tramao in addition to gear motors.
There are hardly any limits to the size and thus
also the performance of geared motors. Small gear motors with 0.1 watt (micro
gear motors) exist as well as large gear motors with 10 MW and more.
In the case of combinations of gearboxes with
stepper motors or servomotors, we also speak of gear motors, which require the
highest level of precision. Integrated incremental encoders complete the
"geared motor" drive unit.
Special gear motors are also available as belt gear
motors or elliptical spline gear motors.
Where can
gear motors be used?
The question has to be, as with the pure electric
motors, where can they not be used. Small gear motors are used in hand tools,
garden tools and kitchen tools in the form of special gears. Further uses are
known from the areas of machine tools, special machine construction, process
lines, construction machinery and conveyor technology.
How can you
get electric motors?
At tramao you will find many different designs of
gear motors. There are new parts as well as used machines or completely
overhauled gear motors.
There are offers from many well-known manufacturers
such as Siemens, SEW Eurodrive, Flender, Stöber, Atlanta, Bauer, Motovario and
Electro Adda.
Here, too, tramao is the right marketplace for gear
motors.