Method and device for correcting backlash

Abstract

A method and apparatus for correcting backlash are disclosed. The backlash width which may occur in the driving device is predetermined and one of the movable directions is selected as a reference moving direction. Further, the state where a movement is made in the reference direction, i.e. the state where the driving device and the driven member come into contact with each other and the positional relationship is unambiguously determined, is made to be a reference state. In this state, a position setting is made that a position detected by a position detector of an absolute position detector secured to the side of the driving means and a position of the driven member coincide with each other. When the operation is performed, a moving direction of an action carried out in response to a movement command immediately after power up is compared with the preset reference moving direction and if both directions do not coincide with each other an excessive movement by the value of the backlash width is made. Accordingly, the actual position of the driven member after the movement and the position detected by the output position detector always coincide with one another irrespective of the state before the power up.

Dependencies are inferred from the claim text.