Abstract: A scanner drive system is disclosed. The scanner drive system has a drive motor. The drive motor has a worm gear attached to the motor spindle. The worm gear has multiple leads. The worm gear is meshed with a helical gear. The helical gear is coupled to a drive train that moves a scanning module.

Abstract: An infinitely variable-speed mechanic drive apparatus is capable of providing a positive non-slip drive and includes a support; a driving shaft mounted rotatably on the support; a driven gear mounted axially and rotatably on the driving shaft; an intermediate transmission member disposed in a transverse direction to and mounted rotatably on the driving shaft. The intermediate transmission member includes an intermediate shaft, a driving wheel mounted rotatably on and shiftable in an axial direction of the intermediate shaft, the driving wheel being in frictional contact with the support, a biasing member biasing the driving wheel towards the axis of the driving shaft, and a driven transmission shaft rotatable around an axis parallel to the longitudinal direction of the intermediate shaft. The driven transmission shaft has a worm member which meshes with the driven gear, and a first drive member transmitting the rotating force of the driving wheel to the driven transmission shaft.