The invention relates to the field of
machining devices, in particular to an inverted type drilling
machine and an operating method for
machining fine
drill holes. The inverted type drilling
machine comprises a base, a stand column, a feed supporting plate, a guide sleeve, a
drill rod box and a drilling tool. A cooling hole of the drilling tool is a through hole. The cooling hole of the drilling tool and an inner hole of the
drill rod box are located on the same center line during installation. A motor used for driving the drill rod box to rotate is arranged in the base. The inverted type drilling
machine and the operating method for
machining fine drill holes have the beneficial effects that the drilling tool is perpendicularly installed on the drill rod box, the direction of the gravity of the drilling tool coincides with the direction of a
drill hole, the situation that deflection of the
drill hole is caused under the effect of the gravity of a
drill bit is avoided, and the machining precision can be improved easily; and the drilling tool is perpendicularly installed on the drill rod box,
scrap iron generated in the drilling process can automatically fall to be discharged from a V-shaped groove of the
drill bit under the effect of
self weight, the requirements for the
oil supply pressure and flow of a cooling
system are lowered correspondingly, heat dissipation in the drilling process is facilitated, and energy can be saved easily.