Wenderoth, Lind & Ponack
Throw-away insert and face milling cutter
 A throw-away insert has four sets of cutting edges with high edge strength and which does not limit the amount which can be cut. An upper half portion of the insert has a set of cutting edges provided at each of two acute-angled corners of a parallelogram. The set of cutting edges includes a major cutting edge defined on one side of the parallelogram and a minor cutting edge defined on the other side and forming an angle of about 90.degree. with the major cutting edge. The lower half portion of the insert has the same structure and dimensions as the upper half portion but is configured as if the upper portion were turned over and further rotated 3.degree.-7.degree. clockwise with respect to the upper half portion. The two sets of cutting edges on the upper half portion and the two on the lower half portion constitute four sets of cutting edges in all. 
Sumitomo Electric Industries, Ltd.
Y B B B B B Y B Y B
Y10T B23C B23C B23C B23C B23C Y10T B23C Y10T B23C
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Mitsuaki Yoshiki Yoshikatsu Naruhito
Noda Maeda Mori Yauchi