Image Description -  0893-table4

A table is captioned “Table 4. Application of BLDC Motors”.  Several
applications have been listed in the first column.  The requirements
for each group of application are given in the second column.  Remarks,
mainly pertaining to the usage of the motor, are given in the third
column.  The first application is centrifuges that have the requirements
of direct control of acceleration, deceleration and speed, unidirectional
rotation, high speed (5000 to 100,000 RPM), as well as design that can
withstand extreme centrifugal forces.  The remarks related to this
application indicate that they are used in industry, science, medicine,
and space experiments as a cost-effective way to separate, by density,
components in liquids.  The next application is fans and blowers that
have requirements of precise speed control, variable speed, constant load,
inertia, long life, and quiet operation.  The remarks indicate that they
are used in space applications such as air conditioning and life support
systems.  Pumps are the next application and they have the requirements
of precise speed control, low maintenance, high starting torque, current
limiting circuits, and variable speed.  The remarks indicate that they
are used in space applications such as environmental control systems,
fluid systems, and thrust vector control systems.  The next application
is servo robotic positioning actuators that have the requirements of
accuracy, stability, four quadrant drive, low torque ripple, bi-directional
rotation, and camping and settling time.  Further they operate in a harsh
environment.  The remark indicate they are used in space robotic arms,
manipulators, and actuators.  The next application is constant speed
controlled capstone drive, timing applications, laser scanners and
precision optics.  The requirements in these applications are speed
greater than 1000 RPM, that a 4 pole motor is adequate, low torque ripple,
toothless stator and accurate speed control.  The remarks indicate that
the designer should discuss the nature of the load with the motor vendor
when considering anything but the basic rotor inertia in precise, accurate
speed applications.  Traction and torquing screw drives and net runners are
the next applications with the requirements of high peak torque, short
acceleration times, large stall torque circuits, and dynamic braking.  The
remarks indicate that choice of motor and drive for torquing applications
involves special consideration of current, heat rise, control type, and
feedback methods.  Additionally these are used for astronaut tools for
extra-vehicular activity.  The final applications are tape transports and
VCR head drives that have the requirements of high starting torque and
smooth motion.  The remarks indicate that to obtain low speeds (less than
100 RPM) usually requires 12 or more poles and flat conditions.  These can
be used for recording the results of space experiments.