Papers by Author: T. Fujiwara

Abstract: In order to establish a high performance grinding method of cemented carbide, the grinding force distribution on the working surface of the cup type electroplated diamond grinding wheel is experimentally analyzed with the grinding force variation of face grinding, which is carried out on the narrow workpiece. The grinding force distribution is obtained by the successive difference of the grinding force variation. The grinding state becomes steady as soon as beginning of the interference of grinding wheel in workpiece, because the edge profile of workpiece is formed as same as the envelope of the grinding wheel. Main conclusions obtained in this study are as follows. In the region of the front edge of the grinding wheel, relatively large grinding force occurs, then in the region of the rear edge of the grinding wheel, the grinding force becomes smaller. In the left right-side end of the wheel, the grinding forces are larger than the center of the wheel. It is made clear that the grinding force distribution shows the peak value near the outer part of the wheel, and the peak value is larger in the center part of the wheel, on the contrary, the peak width become broad in both the left and right-side end of the wheel.

Abstract: In this study, the crankshaft pin grinding mechanism, which is carried out with wheel head oscillating type CNC crankshaft pin grinder, is theoretically analyzed. In order to maintain grinding process, the pin rotates and also rocks along wheel working surface, because the wheel head oscillates with journal rotation. Then, it is made clear that cylindrical plunge grinding process progresses in the pin grinding process for the first time. Therefore, grinding speed ratio, which is defined as ratio of substantial pin surface speed to wheel surface speed, is firstly formulated. Secondly, undeformed chip size generated by a grain is estimated with the grinding velocity ratio. Finally, the grinding performance is predicted with experimental equations, which obtained previous study. By this simulation, it is made clear that dimensional accuracy and also surface roughness vary on whole of the pin surface with constant journal rotation grinding method. On the contrary, deviations of both the dimensional accuracy and the surface roughness are reduced with controlled speed ratio grinding method, in which journal rotation speed is adequately controlled.