Releasable coupling device for lifting objects

A releasable coupling device, especially for use in lifting devices has one or more couplings that are arranged in the lifting equipment or between the lifting equipment and the load. The coupling is locked or opened directly or indirectly through a positional or rotational change of a locking element, which is brought about directly or indirectly by the buoyancy of a floating element or other external force applied. Structural change of one or more metals may be used directly or indirectly to change the position of a release-blocking/locking element between a locked and an unlocked position. This structural change allows imitation through cableless remote control by the use of auxiliary equipment of a known type. Memory metal(s) can be used to change the position of the release-blocking/locking element between a locked and an unlocked position.