| The key to smooth , efficient
overhead monorail operation lies in proper selection of the size and
type of drive unit. Two basic styles of drive are offered as standard by
Anchor: Sprocket and Caterpillar. Each has its own advantages and both
can be fitted to suit virtually any conveyor requirement.
The primary
element to a drive unit is the speed reducer. Anchor drives utilize a
high quality worm gear vertical shaft reducer specifically designed for
overhead conveyor applications. Totally enclosed gearing with drop
bearing construction results in a unit which is strong, uncomplicated,
and easily maintained.
Several approaches are commonly taken to complete the power train of
a drive unit. Most economical are the Fixed Ratio "V" Belt Drive for
constant speed application, and the Variable Speed motor Pulley Drive
which allows a nominal 3:1 variation in conveyor speed. For single
drive applications where no requirements for speed changes or exact
speed settings exist, a Fixed Ratio "V" Belt Drive is used. If either of
these characteristics is required, the Variable Speed Motor Pulley is
the logical choice.
|
Other approaches to the
variable speed drive include variable mechanical transmissions,
hydrostatic motors, AC-DC compound wound motors, eddy current clutches,
and variable frequency AC motors. All of these units have the capability
of remote and/or automatic speed control. The electrical and hydrostatic
techniques also readily adapt to balancing drives for multiple drive
applications. When system requirements result in chain pulls greater
than the recommended allowable rating multiple drive units must be
employed. Special consideration should be given these units regarding
location, size, and power train to insure that the units will operate
efficiently together. Since rivetless OHM chain is not exact pitch, and
conveyor loads will vary, each drive will pass a slightly different
length of chain in a given period of time with constantly varying chain
pull. Motors for each unit will also have slightly different
characteristics. The variables can be efficiently handled to synchronize
constant speed drives through the use of hi-slip motors of fluid
couplings. Variable speed drives require selection of on of the power
trains previously mentioned with automatic control.
General data for Anchor standard drive assemblies will be found
in this section of the Anchor Online Product Catalog. The selection charts shown will allow for initial
sizing of most drives. More specific information concerning exact
ratings, individual components, and drive nits for speeds in excess of
60 FPM is available upon inquiry. |
