geoff said:
No. CD motors spin continuously.
Stepper motors action is to , surprising, step, one distinct step for every
driving pulse. Would not give a very nice clan smooth spin, even at high
speed.
geoff
WRONG !!!!
What makes you think a 'brushless DC motor' is any smoother than a
'stepper motor' ? How many poles does a 'brushless DC motor' have ?
What is the size of the 'step' for a 'brushless DC motor' (they don't
actually work with just DC, do they ?)
How many poles does a' stepper motor' have ?
Neither type has commutators, so any 'smoothness' is entirely due to the
design of the drive electronics, and is ultimately limited only by the number
of poles, isn't it ?
You clearly do not understand the construction of these types of motor.
There is really ****-all difference between what is called a 'stepper motor'
and what is called a 'brushless DC motor'.
Mechanically, they are virtually identical. The differences lie mostly in the
drive electronics (for the application), and the way the stator coils are terminated.
A 'brushless DC motor' usually (but not always) has Hall-effect devices
mounted to sense the rotor position and control the phase of the (typically)
3-phase coil drivers, while 'Stepper motors' usually don't have rotor sensors,
but have more poles in the rotor.. ...
Have a look at the May 2008 issue of Silicon Chip, page 16.
Leo Simpson argues that 'In reality, there is no such thing as a brushless
DC motor', and I totally agree that the terminology is misleading.