Infranor

Cut-to-length

CUT-TO-LENGTH IN AN INCREASED SAFETY ENVIRONMENT

For the feed and cut of a sensitive material, the application requires highly dynamic response in the intermittent double feeding mechanism, as well as a synchronisation with the vertical cutting eccentric lever driven non stop rotating movement.

Challenge

The special material is fed intermittently in two parallel lines to the cutting station and, because of his characteristics, ATEX servomotors must be used. The drives are mounted in a special electrical enclosure.
The vertical cutter is moving constantly, and depending on the part reference to be produced, the feeding length is adjusted accordingly.
The feeding time must be accomplished within 150 ms in the machine's secondary shaft. The feeder is dual, and the two motors running at the same speed must enhance the movement in a fraction of this time due to the pinions transmission ratio.

Needs and requirements
It is necessary to synchronise the movement of the two mechanisms in a non-stop operation, and a different program must be performed depending on the feeding length.

Solution

The complete equipment mounts #3 AC brushless XA-30 servomotors in resolver feedback with #3 Drives INFRANOR CD1a-400/45 type.
The connection between encoder output from the master drive to the encoder input of the slave drive, in addition to the encoder signals must carry the +5V and GND.

Technical Concept

This is a P. L. C. based system with Profibus interface protocol module. The ‘bus' is used to call the sequence number, and after a ‘Homing' sequence, both drives start running the next sequence at the same time, with one feeding servodrive as Master of the second feeder motor, which in-turn is Master to the eccentric cutter servodrive running as Slave.

Electronic gearing value settings must be established at the start up in the CD1-pm drive using the Visual SetUp software.
The master-slave operation requires resolver feedback in all the motors.

The mechanical assembly for the cutter is filled with oil that reaches a temperature above 50ºC because of the constant operation. Such value must be considered in the motor selection as it might cause a lower motor dissipation, this producing a de-rating of the available output torque.

Even if the two feeding systems start exactly at the same time, the same voltage applied to two motors of the same reference does not guarantee an exact speed, because of the +/-5% tolerance in their EMF constant values.

Used Infranor products

Customer‘‘s benefit / Why Infranor

The wide product range including ATEX servomotors enhances more opportunities to the OEMs to participate in new projects. The local support in the country permitted the development of the application from the initial steps.

Further Information

E-Mail: mavilor@mavilor.es