1987 年 53 巻 12 号 p. 1887-1892
This paper describes a new device which can automatically measure the lead error at the cutting edge of threaded cutting tools such as gear-hobs and taps. Firstly, a new precise main spindle with a precise rotary scale, a new-type photoelectric feeler, and an angular position detector for cutting edge are developed. Secondly, the non-contact-type automatic measuring machine is produced, combining them with a tool makers' microscope, laser length measuring system and a microcomputer. Thirdly, the program for the control of the machine and for the measurement are developed, and the cumulative lead error and the cumulative dividing error of the cutting edge are computed from the detected values by the microcomputer and recorded by a printer or a plotter. Finally, in order to investigate the accuracy of measurement in this machine, the experiments are carried out. The main results are as follows: (1) The precision of measurement for the lead error in the gear-hob is 0.16μm for repeatability in standard deviation. (2) The detective precision for the angular position of the cutting edge is about 10'' for repeatability in standard deviation.