| 摘要 |
PURPOSE:To prevent vibration of an object chucked due to out of centering alignment and provide possibility of judging that the object is chucked properly by furnishing a receiver part of hard material which receives the end face of a rotary cylinder when the object is fastened and by arranging a plurality of elastic rollers which can retract till the position to allow pressure contact of the rotary cylinder with said receiver part. CONSTITUTION:When a cutting tool 32 is set in an insert hole 4 and a rotary cylinder 17 is turned clockwise, a number of rollers 24 are pressed by guide edges into rotation in such a location relation with the center axis 31 as twisted, so that the rollers 24 advance spirally toward a receiver part 8 if the rotary cylinder 17 is rotated while rolling between the external surface 7 and internal surface 18. Thus the rotary cylinder 17 is pressed and contracted by the receiver part 8 so as to reduce the dia. of a fastener cylinder 3, so that the fastening surface 5 is put in close contact with the outside surface of the cutting edge 32 to yield tight fastening. Here elastic rollers 12 deform elastically one after another, and when rotation is stopped where an interpositional part 14 is in pressure contact with a receiving surface 9, the contacting surface 20 is put in pressure contact with the receiving surface 9. Eventual application of any force to the tip of the tool 32 will not cause vibration of the fastener cylinder 3 due to out of centering alignment because it is as in a single piece with the rotary cylinder 17 and also its contacting surface 20 with the body 1. |
