Bipolar stepper motor
is known by its open loop feedback system; this characteristic makes the user
know the exact position of the system driven by the bipolar stepper motor
without any sensor and closed loop.
This is why we
find bipolar stepper motor on different fields like lasers fields, optics
fields, printing fields ...etc.
Commercially
bipolar stepper motor are used many devices and machines such as Computer
Numerical Control (CNC), Robotic arms , Scanners, Printers, CD/DVD and Blu-ray
readers ...etc.
As said before
Computer Numerical Control (CNC) are based on two or three Bipolar Stepper
Motor to control the axis’s position and gives to the industries an opportunity
to sculpt some CAD designs into metal and glasses plats.
Their high reliability
makes them favorite by constructors with an excellent response to starting,
stopping, and reversing sense.
Although the
advantage of the precision characteristic that enjoys stepper motors, the speed
is its blame. Synchronous or asynchronous motors often reach 3000 rev/min
easily, but bipolar stepper motor rarely exceeds 3000 rev/min and this with
high quality motors equipped with ball bearings.
Another negative
point of stepper motors is the mass that they load to be driven which it’s
recommended to not to be heavy, usually between 3 Kg to 10 Kg (6.6 lbs to 22
lbs).
That’s why all
devices controlled by stepper motors are use not very heavy. Therefore there is
some technics to control such heavy axes with bipolar stepper motor, like distribute
the weight between two or three motors to load those axes but the constructors
should provide the totally synchronization in this case. The torque converter
technics could also load those heavy axes. This technic may also improve the
speed.
In general to
control a bipolar stepper motor we have to use drivers which connect the
control supply (5 to 24V) with the power supply (24 to 150V), there are different
driver schema to use, here is two examples of control drivers:
Robotic arms
often use bipolar stepper motor to control their motion by a parametric program
user from an API or an industry computer.
Usual scanners,
printers or CD readers are controlled by an integrated circuit to control a
unipolar stepper which its command are simple than bipolar and offer the same
proprieties.
