抄録
This paper shows the transient phenomenon of chip formation and behavior in simulation tests of hobbing by using a high-speed video camera. Scratches occur on tooth surfaces and cutting edges chip when the chip jams between the tooth and the cutting edge. As a result, tooth surfaces degrade and abnormal tool wear occurs in dry hobbing. Chips produced by hobbing are classified roughly into three types; the "U", "J" and "I" types are represented in this paper. This paper presents findings of the "J" and "I" type-chip movements in flytool simulation tests. In the "J" type-chip, a part of end side of the chip produced by the top cutting edge is often jammed into the finished surface being pushed by the chip from the side cutting edge. The "I" type-chip flows from the root to the tip side of the cutting edge, and the pointed end of the chip is jammed into the space in down cut method. In up cut method, the chip flows to the root side on the rake face, and the jam of chips occurs as well as the case of down cut method. Jamming mechanism in hobbing is discussed from the results of flytool tests.
