To provide an oil hole structure of a crankshaft capable of securely removing burrs at the connection part of two linearly extending oil holes and a method of manufacturing the crankshaft.
The oil hole 3 drilled from a crank pin 5 toward the oil hole 2 drilled in a crank journal 4 is formed to cross the oil hole 2 at a predetermined included angle. A pocket 11 with the same outer diameter dimension as the oil hole 3 and a predetermined depth P is formed at the extension part of the oil hole 3. When a flushing fluid 12 is fed from one end 3a of the oil hole 3 with a nozzle in a burr removal step, the flushing fluid 12 (flushing fluid flow) advances straight through the oil hole 3 toward a crossing part 10 with the oil hole 2 and is rushed into the pocket 11 formed at the extension part of the oil hole 3. Then, the flushing fluid rushed into the pocket 11 is diffused at the crossing part 10 between the oil hole 2 and the oil hole 3, and the burrs 7 formed at the crossing part 10 between the oil hole 2 and the oil hole 3 can be efficiently removed with the flushing fluid 12 diffused in the pocket 11.
Miyazaki Yoshio
Kaoru Onozuka
Akio Tagami
High Masahiro
Toshio Nakamura
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