Siemens simovert masterdrives

08.2012 Technology Option F01
Siemens AG 6SE7087-6QX70 (Version AN)
SIMOVERT MASTERDRIVES Compendium Motion Control 9-11
The printing index controller (position correction) acts in combination
with suitable reading devices to control the orientation of the master
and slave drive in relation to each other. The synchronization signal is
evaluated by a high-speed interrupt-capable digital input with a
resolution of several µs. The velocity at which the orientation or
correction movement is performed is adjustable.
An example of printing index evaluation is a packaging machine in
which a continuous stream of products has to be packaged in film, such
that the printed image on the packaging film always appears in the
same position. By detecting the printing index on the film, the film
expansion (or film contraction) can be measured and automatically
corrected. Drift effects, which would be apparent without a printing
index controller, are thus eliminated reliably.
The figure below illustrates the principle of printing index
synchronization
Printing indices, e.g. on film
360 °
v
Slave
Actual position
master
Printing
index
too early
slave decelerates
Printing index too late
slave accelerates
360 ° 360 ° 360 ° 360 °
Position setpoint - printing index
Actual position - printing index
Fig. 9-8 Principle of printing index synchronization
The referencing "on the fly" function enables synchronization to a
reference index (e.g. BERO proximity switch) to take place "on the fly"
in synchronization mode.
It is no longer necessary to first approach the reference index in
positioning mode and then change over to synchronization mode from
standstill.
The "Synchronization to master value" function enables the position of
the slave axis to be matched to the position of the master axis during
synchronization. The speed and acceleration of the compensation
movement required for this are adjustable.
Printing index
controller [843]
Referencing "on the
fly" [843]
Synchronization to
master value [841]