Abstract: A main CPU unit and a plurality of CNC units provided on a one-to-one correspondence with machine tools, and the main CPU unit is connected with an external storage device and an input device. To modify the mode of machine tool control or machining data of work, a new system program is down-loaded through the RAM of the main CPU unit into the CPU for the CNC unit, and according to this new system program, the part program including machining data normally stored in the CPU for the CNC unit.

Abstract: Ratios between a distance between an upper wire guide and the upper surface of a workpiece to be machined, a thickness of the workpiece and a distance between a lower wire guide and the lower surface of the workpiece are given to the inlet and outlet positions of a wire electrode at the upper and lower surfaces of the workpiece which have been interpolated so as to directly obtain displacement positions of the upper and lower wire guides, along which the upper and lower wire guides are moved successively, thereby obtaining an articles which is accurately machined with a relatively simple machining procedure.

Abstract: A cleaner comprising a rotary drum, radial rubber blades attached to the outer surface of the drum, and abrasion-resistant ceramic members each secured to the outer edge portion of each of the blades.

Abstract: The method for controlling the withdrawal of the electrode in an NC electric-discharge machine permits a linear withdrawal of the electrode to a forward position at least two blocks preceding the present forward position from the workpiece according to a withdrawal command received by the NC unit and with a high efficiency while a workpiece is being machined with electric discharges made between the electrode and the workpiece with the former being forwarded in relation to the latter according to a control information including positioning commands given to the NC unit for each block.

Abstract: In a coordinates detecting device comprising: a cursor; a tablet in which conductors are arranged in a predetermined periodic pattern; and arithmetic means for calculating the position of the cursor according to the outputs of the tablet, correction values for correcting the errors which are caused in common with all the periods of the pattern and in correspondence to the positions in each of the periods have been stored in memory, and the position of the cursor calculated by the arithmetic means is corrected by using the respective correction value.