Slaving and blocking device

A hand power tool, comprising a tool bit;

• a spindle that carries said tool bit;
• an electric motor rotary drive for rotationally driving said spindle that carries said tool bit;
• and a slaving and a blocking device located between said rotary drive and said spindle, said slaving and blocking device including a slaving means fixable on the driving part in a manner fixed against relative rotation and having slaving claws, offset from one another in a circumferential direction, with slaving faces provided on sides facing away from each other and pointing in the circumferential direction;
• a roller star wheel connectable to the driven part in a manner fixed against relative rotation and having points of a star, offset from one another in the circumferential direction, with contact and clamping faces embodied on sides facing away from one another;
• clamping rollers located in freewheeling fashion in the circumferential direction between said slaving claws and said points of said star;
• a stationary clamping ring located concentrically with said slaving means and said roller star wheel and having an inner annular face forming a counterpart clamping face for said clamping rollers, said contact face on said points of said star being configured so that said clamping rollers, which when said slaving means is driven are pressed by said slaving claws against said contact faces of said points of said star, are thrust inwards, and said slaving faces on said slaving claws are configured such that when said slaving means is driven, they load said clamping rollers with a pressure force such that a tangential force component of the pressure force is substantially greater than a radial force component of the pressure force.