| 摘要 |
PURPOSE:To enhance accuracy for parallelism by a method wherein a control system which memorizes such fluid pressures of static pressure beargins as deviations from values of parallelism between a guide axis and movable racks at respective locations along the guide axis have been adjusted to be zero, carries out control in a way to cause deteted values of fluid pressures to become identical with the stored pressure values respectively. CONSTITUTION:Distances between a reference plane X-X and a side of each movable rack which is in parallel with the reference plane at points X1, X2, X3 and X4 along the guide axis 3 are referred to as 1AX1, 1AX2, 1AX3 and 1AX4 respectively. Fluid pressure supplied to respective static pressure bearings 11 on one side are properly adjusted to make differences among the distances 1AX1, 1AX2, 1AX3 and 1AX4 zero and each of the adjusted values of fluid pressures at respective points is stored in a memory unit 20. As signals indicating location of a movable rack 1 are sent to the memory unit 20 from a pulse motor 5, the memory unit transmits a value of fluid pressure at that specific location as form of a signal to a comparison circuit 21 where comparison is made between the received signal and a signal from a detector 9. Then, the comparison circuit transmits signals to a drive unit 22 of a control valve 10 so as to cause resultant difference from the comparison to become zero. |
