Manually operated screwdriver, comprising transmission gear unit integrated in handle

摘要

The tool is assembled of a shaft (D) with a tip appropriately shaped for the type of screw to be driven at its lower end and a handle (A), accommodating a transmission gear unit. When the handle is rotated the torque is transmitted to the inner teeth acting on two planetary wheels (C) meshing with an outer toothed area (B) arranged around the upper end of the shaft. The gear ratio can be selected according to the type of screw to be moved.