Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: A tool holder includes a drawing screw and a stopper member. The drawing screw is positioned in an intermediate hole. A rear end face of a head of the drawing screw faces a boundary wall surface, and a top end of a shaft of the drawing screw is screwed in a rear end of a collet. The stopper member is positioned in an annular space between an outer peripheral surface of the shaft of the drawing screw and an inner peripheral surface of the intermediate hole. The stopper member faces a front end face of the head of the drawing screw, and limits movement of the head toward a top end of the tool holder. The drawing screw and the stopper member are inserted and assembled from a top end opening of a collet holding hole.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: A tool holder, which is inserted into a center-through-coolant spindle and employs a side-lock type chuck structure, can reliably prevent leakage of cutting liquid from a bolt hole for a side-lock bolt. The tool holder includes a side-lock bolt and an annular seal member. The side-lock bolt is inserted into a through hole extending from an outer peripheral surface to an inner peripheral surface of a tool attachment portion, threadedly engaged with an internal thread formed in the through hole, and secures a shank of a tool to a tool-holding bore. The seal member seals between the through hole and side-lock bolt.

Abstract: A tool holder includes a drawing screw and a stopper member. The drawing screw is positioned in an intermediate hole. A rear end face of a head of the drawing screw faces a boundary wall surface, and a top end of a shaft of the drawing screw is screwed in a rear end of a collet. The stopper member is positioned in an annular space between an outer peripheral surface of the shaft of the drawing screw and an inner peripheral surface of the intermediate hole. The stopper member faces a front end face of the head of the drawing screw, and limits movement of the head toward a top end of the tool holder. The drawing screw and the stopper member are inserted and assembled from a top end opening of a collet holding hole.

Abstract: In order to provide a tool holder which greatly reduces frictional resistance between a locknut and a taper collet, and eliminates a twisting of the taper collet during tightening of the locknut, in a tool holder comprising a locknut 13 which pushes a taper collet 12 into a tapered hole 115 of a collet chuck body 11 to chuck a cutting tool 15, between a reference end 123 of the tape collet 12 and a collet supporting portion 131 opposed thereto, interposed is a bearing washer 14 to reduce frictional resistance between both contact surfaces. To both surfaces of this bearing washer 14, namely, to the respective surfaces which come into contact with the reference end 123 and collet supporting portion 131, surface treatment by any of ion nitriding, DLC (Diamond-Like Carbon) coating, and TiN coating is applied.

Abstract: In order to provide a tool holder which greatly reduces frictional resistance between a locknut and a taper collet, and eliminates a twisting of the taper collet during tightening of the locknut, in a tool holder comprising a locknut 13 which pushes a taper collet 12 into a tapered hole 115 of a collet chuck body 11 to chuck a cutting tool 15, between a reference end 123 of the tape collet 12 and a collet supporting portion 131 opposed thereto, interposed is a bearing washer 14 to reduce frictional resistance between both contact surfaces. To both surfaces of this bearing washer 14, namely, to the respective surfaces which come into contact with the reference end 123 and collet supporting portion 131, surface treatment by any of ion nitriding, DLC (Diamond-Like Carbon) coating, and TiN coating is applied.