Abstract: A cylindrical cam is obliquely mounted on a drive shaft to be shiftable in the axial direction. The cam and the drive shaft are concentric at the axial center and the eccentricity of the cam increases gradually towards the opposite ends and in opposite phases. A pair of contact members carried by a follower member engage the opposite sides of the cam. As the drive shaft is rotated a reciprocating motion is imparted to the follower member and by shifting the cam in the axial direction the amplitude of the reciprocating motion can be varied.

Abstract: In the apparatus for creating a swinging motion, one ends of two opposed sides of a flexible link are secured to a stationary member and the opposite ends of the sides are connected to a driven shaft. A cam member is slidably mounted on a drive shaft and arranged between the two sides so as to continuously engage them when the cam member is rotated by the drive shaft. The cam has gradually varying configuration and when it is shifted along the drive shaft, the swinging angle is varied. By suitably constructing the cam member it is possible to stop the swinging motion and reverse the phase thereof.

Abstract: In apparatus for imparting a swinging motion to a driven shaft from a drive shaft through a pair of eccentric discs or crank pins mounted on the drive shaft and link mechanisms, the link mechanisms comprise a pair of flexible links. Each link has a loop at one end thereof which encircles the eccentric disc or crank pin. The other ends of the links are connected to the driven shaft such that the other ends are wrapped about the driven shaft in the opposite direction and over an angle larger than the swinging angle of the driven shaft.