Bore drilling tool has connection section with specific portion whose taper diameter is smaller than drill bit diameter of drill bit portion whose deflection is enabled with respect to central axis of clamping portion

摘要

The tool has clamping portion (1) that is provided with central axis (M). The clamping portion is provided towards the connection section (2) that is provided towards the drill bit portion (3) with specific drill bit diameter. The taper diameter (D2) of the specific portion (4) of connection section is smaller than drill bit diameter of the drill bit portion. The deflection of drill bit portion is enabled with respect to central axis of clamping portion.