Blind rivet fastening device

A blind rivet fastening device for deforming a sleeve of a rivet body so as to expand diametrically by drawing, in the axial direction, a mandrel of a blind rivet including a mandrel and a rivet body, thereby fastening the rivet body to a mounted member via the expanded sleeve portion and a flange of the rivet body, and breaking the mandrel, the blind rivet fastening device characterized in comprising:

• an electric motor provided on one end;
• a power transmitting means for transmitting the rotation of the electric motor;
• a spindle provided in front of the electric motor and rotated by the power transmitted by the power transmitting means;
• a ball screw nut adjacent to the spindle, and connected to and rotated by the spindle;
• a ball screw shaft provided in the central portion of the ball screw nut in the axial direction, and moved in the axial direction by the rotation of the ball screw nut;
• a drawing means connected to the ball screw shaft for gripping and drawing a shaft portion of the mandrel;
• a rotation count detecting element for detecting the rotation count of the electric motor;
• a trigger provided in a handle portion;
• and
• a control means for controlling the forward rotation, reverse rotation, and stopping of the electric motor based on operation of the trigger and the rotation count of the electric motor;
• a first clutch including a spindle clutch and a nut clutch, the first clutch positioned between the spindle and the ball screw nut, and a second clutch which includes a rear clutch and a front clutch is positioned in front of the ball screw shaft, wherein the first and second clutches are provided to keep excessive tongue from moving the pulling head beyond the range defined by the home position HP and the rear position RP.