To uniformly chamfer an edge of an inclined hole formed in a direction inclined to a normal line of the surface of a workpiece.
A pair of blades 16, 17, which is vertically movably provided to a body 13 rotating around an axial line Lt, is biased upwardly with coil springs 19, 20 respectively having different resilient forces so as to be brought into contact with both end parts of an oscillation link 15 whose central part is freely oscillatingly pivoted to the body 13. One blade 16 is thereby protruded further downwardly than the other blade 17 due to a difference between resilient forces. Accordingly, when a chamfering tool T is brought close to the inclined hole H inclined to the normal line N of the surface of the workpiece W, the other blade 17 is pushed down while the one blade 16 is pushed up by being brought into contact first with the edge of the inclined hole H so as to bring a pair of the blades 16, 17 into contact with the edge of the inclined hole H with equal pressure. The edge is uniformly chamfered while preventing chamfering blades 16a, 17a formed at the lower end of the blades 16, 17 from cutting into the edge.
IKEDA SHINYA
ONO SHINKO
ARAHORI KATSUHIRO
HAYASHI TETSUYA
OTANI TOMOYA
Kazuaki Niki
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