Tool of machine tool

A tool of a machine tool comprising:

• a tool body, the tool body comprising:
• a shaft portion attachably/detachably loaded to a spindle of the machine tool via a tool holder;
• a holding portion provided with a plurality of cutting edges;
• and a suction hole serving as a suction passage of chips during suction of the chips by a chip suction device,
• wherein the plurality of cutting edges are disposed along a peripheral edge of the holding portion of the tool body and are fixed to the holding portion by bolts inserted from underneath;
• in the holding portion, a plurality of concave portions are formed along the peripheral edge of the holding portion so as to be situated on a front side of the cutting edges, in terms of a cutting direction, the concave portions are open downward and covers are provided so as to cover the openings of the concave portions from underneath, the covers are formed as separate bodies, and gaps between the covers and the cutting edges which communicates with the concave portions,
• wherein the suction hole includes:
• a plurality of first suction passageways communicating with the concave portions and extending obliquely upward toward an axis of the shaft portion;
• and a second suction passageway which is partially formed in an axial core of the tool body so as to extend in a direction of the axis of the shaft portion and to which the plurality of first suction passageways join, and
• wherein each of the plurality of first suction passageways includes an end abutting corresponding one of the concave portions, and
• wherein the end is arranged to overlap at least partially with corresponding one of the gaps, when viewed from a bottom of the tool.