US Patent 7784603 Gripping device for containers

A gripper for containers, in particular for bottles, with at least first and second gripper arms (1, 2) which are mounted such that they can pivot and are acted on in the gripping pivoting direction by magnetically interacting permanent magnets such as, permanent magnets which simultaneously repel one another and attract one another are arranged in such a way that the sum of the repelling and attracting forces which act in the gripping pivoting direction on the gripper arms is substantially constant within a predetermined gripping range (d1 to d2) of the gripper which covers different container gripping sizes.