| 摘要 |
PROBLEM TO BE SOLVED: To provide a driver bit capable of removing M3, M4 screws of a different type by one driver bit without replacing, and capable of smoothly removing the loosened screws from the driver bit with the reduced risk of a fitting part on the tip fixed to the cross recess of the screws.SOLUTION: The driver bit comprises a fitting part 2 fitted to a cross recess formed in a head part of a screw of a separation object on the tip. The fitting part comprises blades 3 each extending in a radial shape from an axis and formed every 90 degrees in the circumferential direction, and guide grooves each formed between the blades 3, to have a cross shape in a front view. An distance between apices on the tip of the blades arranged in an opposed position is set in a range of 1.45 mm-1.75 mm. A distance between bottoms on the tip of the guide grooves arranged in the opposed position is set in a range of 1.15 mm-1.35 mm. |
