轴线偏移特点。轴线偏移导致刀具在导套里倾斜,并引起刀具端部在同工件接触时偏离给定位置产生偏差(图70)。情况Ⅰ是刀具和导套轴线完全重合;情况Ⅱ是钻头与可换导套之间有间隙,而且固定套和可换导套之间偏向一边,钻头仅在导套出口处一面接触;钻头没有弯曲。情况Ⅲ是轴线位移量增加到钻头刃带沿导套母线全长接触; Axis offset characteristics. The axis offset causes the tool to tilt in the guide sleeve and cause the tool tip to deviate from the given position when in contact with the workpiece (Figure 70). Case Ⅰ is completely coincident with the axis of the tool guide; Case Ⅱ is a gap between the drill bit and the guide sleeve, and between the fixed sleeve and the guide sleeve biased side, the drill bit only contacts the exit side of the guide sleeve; bending. Case III is the axial displacement increases to the drill edge along the entire length of the guide bush busbar contact;