The principle of an unwinding cradle is that the roll is placed in a cradle consisting of several driven rollers so that the roll can be rotated and the tail end positioned at a sewing machine or the like. The driven rollers are synchronised with the following drive roller for exact tension control. An unwinding cradle is most suitable for compressed / tightly wound rolls.
Lifting arm unwinder
The procedure when applying a lifting arm unwinder is to place the roll in front of the unwinder, place a shaft in the core of the roll, and subsequently the roll can be lifted by means of the lifting arms. The lifting arms can be either pneumatic or hydraulic dependent on the roll weights / dimensions. Unwinding takes place when the following drive roller pulls off the carpet from the roll, which is free-running on bearings mounted in the lifting arms.
Driven lifting arm unwinder
A more precise way of unwinding can be carried out by means of a lifting arm unwinder with driven roll. Each lifting arm is equipped with an air chuck which is led into the core of the roll, it expands and rotates the roll. The speed of the roll is synchronised with the following drive roller by means of a tension regulator.
If the cores are not capable of supporting the rolls by themselves, a solution with loose, through-going air expansion shafts can be quoted, which are placed in safety chucks on which a drive motor is mounted.