Abstract: If an instruction indicating advance is input, first and second motors are driven to rotate first and second torque wires. A rotary body is circulated by the rotation of the first and second torque wires, and a propelling unit advances. The first and second TGs detect the rotating speeds of the first and second torque wires. If disconnection of the first torque wire is detected by a disconnection detecting section, a motor control section stops driving of the first motor coupled to the disconnected first torque wire, and rotates the second motor coupled to the second torque wire that is not disconnected at a low speed to rotate the second torque wire at a low speed. Through the low-speed rotation of the second torque wire, the propelling unit advances at a low speed or retreats at a low speed.

Abstract: An insertion and extraction assisting device of an endoscope has a promotion unit attached on the front end side of the endoscope and a transmission section whose one end is connected to a promotion unit, and the other end is drawn along the endoscope, and an outside unit. The other end of the transmission section is connected to the outside unit, and rotational force or a turn signal from the outside unit is transmitted to the promotion unit, so that driving force is generated by the promotion unit. When the other end of the transmission section is connected to, the outside unit reads an ID code expressing a kind of the promotion unit and controls the rotational force or the turn signal to send to the promotion unit.