Article deals with the field of machinery, namely with the protecting of devices for mechanical driving systems. New construction of safety-overrunning clutch, operating on gearing principle, where safety and overrunning parts are mutually integrated, has been proposed and studied in the article. It has practical importance for building, based on modular principles, machines. As the result of the theoretic studies, the expressions to calculate the following specific clutch torques have been obtained: rating torque, torques of beginning and ending of operation. On the basis of the mentioned studies, the expressions to estimate the clutch main operation characteristics have been obtained - nominal torque exceeding coefficient, accuracy and sensitivity coefficients. These expressions are practically important for proposed clutch calculations. The analysis performed demonstrates that in order to increase the clutch load capacity, the grooves must be made with less inclination angles to clutch axis. Obtained results indicate the advisability of installing the clutch on low-speed shafts. It is shown that the clutch overload sensitivity could be increased by the reduction of the spring rigidity. It is shown that in terms of the accuracy of operation, the studied coupling fully corresponds to the level of common and investigated designs of safety clutches.