Patent ID: 8653766

Claim:
A driving system of a linear motor, comprising: a linear motor including a movable member and a plurality of stators, the movable member being provided with a magnet portion and a scale portion, the magnet portion including a plurality of magnets arranged side by side, the plurality of stators each including a coil and a position sensor for detecting, from the scale portion, a position of the movable member in a moving direction along which the magnets are arranged side by side, in which the movable member moves in the moving direction; and a plurality of driving devices each of which controls an electric current flowing the coil of the corresponding stator, wherein the plural stators are arranged in the moving direction of the movable member, a distance between the coils of the adjacent stators is less than a length of the magnet portion in the moving direction of the movable member, and a distance between the position sensors of the adjacent stators is less than a length of the scale portion; and wherein each of the driving devices includes a position controller for performing position controlling by calculating a deviation between a position command value from a controller and a position detected by the position sensor of the corresponding stator and then calculating a speed command to be used for the speed controlling of the movable member based on the deviation and a position gain, and a back-calculating unit for back-calculating the deviation with the moving speed of the movable member being as a speed command and then back-calculating the position of the movable member from the deviation and the position command when the movable member enters a control area in which at least one of the magnets of the magnet portion opposes to the coil of the stator within an area of which a position is detected by the position sensor of the corresponding stator, in which the position controller performs the position controlling by correcting the position detected by the position sensor with the position calculated by the back-calculating unit being as a position of the movable member at a time when the movable member enters the control area.