Lightning protection type mechanical inner capacity indicator for storage tank

The utility model belongs to the technical field of industrial storage tank monitoring and lightning protection safety, and relates to a lightning protection type mechanical internal capacity indicator for a storage tank, which comprises a rotating shaft, a balancing device and a floating device arranged in the storage tank, the height of the floating device moves up and down along with the change of the capacity in the storage tank, and the floating device drives the rotating shaft to rotate through a connecting rope; the balancing device is connected with the rotating shaft and is used for balancing the stress of the rotating shaft; the rotating shaft is provided with a mechanical dial plate, and the angle displacement of the rotating shaft is converted into the storage tank inner capacity to be displayed through the mechanical dial plate. The mechanical internal capacity indicator does not need an external power supply, ensures that an operator can know the capacity of a medium in a storage tank under the