At present, most of the cling film rewinder used in China use conical top chucks to clamp the unrolled cling film rolls. When clamping in this way, the unwinding shaft does not rotate, so the film roll is usually braked by friction between the belt and the film roll surface.
In this type of device, by adjusting the lead screw, the conical top central head can be moved axially along with its support to clamp the cling film roll from the left and right sides. This structure does not require the operator to load and unload the unwinding shaft when changing the cling film roll, thus greatly reducing the labor intensity.
There are many specific structure types of the air expansion mandrel, but the principle is the same, that is, the tube is used as the mandrel and the plastic film roll is clamped on the main tube. Long hole, the hole is equipped with a correspondingly shaped tension block, the bottom surface of the tension block is fixed with a spring supporting plate, and there is an elastic air cavity in the inner hole of the tube. When compressed air is filled in the gas amine, the air cavity expansion fertilizer will The tension block is pushed out to form a convex surface, which can clamp the core of the plastic wrap.
