PCM-22 Rotary Knife Controller
42
© EMERSON Motion Control
Follower Cycles
A
Follower Cycle Length
is the distance between successive Follower zero
positions. The PCM-22 allows the drive to position and maintain a phase
relationship of its motor to an independent axis. The FX drive, with the
PCM-22 acting as the Follower axis, will produce one or more cycles of
motion for every cycle produced by the Master axis.
FX AMPLIFIER WITH PCM-22
1 = MASTER CYCLE LENGTH (5 INCHES)
2 = MASTER PHASE DISTANCE (9 INCHES)
REGISTRATION
MARKS
FOLLOWER
AXIS
FOLLOWER
SENSOR
MASTER AXIS
(SYNC ENCODER)
MASTER SENSOR
1
2
ROTARY KNIFE
CIRCUMFERENCE = 6.28
INCHES
Figure 22
System Example
The system example above shows a flat product (such as paper or plastic)
that moves through a set of pinch rollers which feeds back Master axis
positional information to the PCM-22 using an encoder. The Master
(registration) sensor allows the PCM-22 to reference the registration
marks on the product in relation to the
Cycle Point
. Similarly the
Follower sensor provides reference information for the Follower axis
using a registration mark on the rotary knife and the motor provides
feedback information of the Follower axis’ position. In this example, the
Cycle Point
will be directly on the registration mark and there would be
one Follower cycle completed for every Master cycle.
Note:
Typically, the Zero Follower Cycle sensor would also be used
as a Home Sensor (0 or 1) for the Follower axis. These input
functions (15 or 40 and 45) would be assigned to the same FX
input line (1 or 2).
