Abstract: In a belt conveyor, when an input lever is rotated in a fixed direction, an input shaft is rotated and a fourth gear fixed on the input shaft is rotated integrally in the same direction. Then, second and third gears are rotated in fixed directions and a first gear and a drive shaft are rotated in fixed directions. Thereby, a spiral spring connected to the drive shaft is wound up stronger little by little so as to store an elastic energy. If a rotating angle in the given direction comes to about 150 degrees, an end of a toothless portion of the fourth gear arrives a meshing part with the third gear so as to disengage from the third gear. Thus, a rotary shaft and the drive shaft are respectively rotated in reverse directions to the give directions by the releasing energy of the spiral spring. Consequently, the drive roller is rotated in a counterclockwise direction so as to drive a conveyor belt in a given direction.

Abstract: The present invention can provide a method and an apparatus for bending a pipe whose bending cross section has reduced compressed ratio, reduced reduction ratio of area and reduced reduction in thickness and in which bending can be conducted at the desired curvature. In the present invention, both edges of the pipe bending portion are arrested and grasped, a center of one bending edge is set to be the axis and a revolution axis is amounted on it, a rotation axis is mounted at a center of the other bending edge and gears are installed on the revolution axis and the rotation axis so as to engage each other so that the driving is driven to the gear on the rotation axis. The rotation axis revolves having the radius to be the distance from the rotation axis to the revolution axis and at the same time the rotation axis rotates on its axis having the radius of the gear in response to the revolution angle.