Rotary Knife application

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Description

Application: Cutting of material without stopping the supply of the material. For this the blade must accelerate or decelerate if the blade is not in contact with the material to be cut.

Application areas: The rotary knife is used in various production processes and in the printing industry.

Function: Rotary knives consist of a rotating cylinder with a blade mounted lengthwise. The speed of rotation of the cylinder determines the length of the material to be cut. The greater the speed, the shorter the pieces cut. In order to ensure an optimum cut, the speed of rotation of the blade and the supply speed of the material must be absolutely identical at the moment when the material is cut.

Solution

The system was implemented with BSH servo motors. These servo motors are compact, have a low moment of inertia, reach high speeds and can rapidly accelerate and decelerate. The motor parameters are automatically loaded by the Lexium 05 servo drives via the integrated SinCos encoders. The multi-turn absolute encoder allows the machine to retain its current positions in the case of under voltage so that additional homing is not required.
The first servo drive keeps the roll with the material under constant tension with the set torque.
The second servo drive controls the supply speed of the material.
The third servo drive controls the speed of the rotary knife.
The Lexium Motion Controller (LMC) and the application function block rotary knife considerably reduce the programming time and improve the machine performance.
The operator can monitor and change the production parameters via a Magelis HMI terminal.

Products used:

• Lexium Motion Controller (LMC),
• Lexium 05 Servo Drives,
• Linear Motion.