| 摘要 |
PROBLEM TO BE SOLVED: To improve the precision of a drilling state in drilling at an optional angle even without using other members such as a guide, etc. SOLUTION: An angle detection means 61 to detect an angle of a main body 1, a computing means 64 to compare and compute a detection angle of the angle detection means 61 and a previously set angle with each other and an angular difference showing means 65 to show difference of the detection angle and the set angle by output of the computing means 64 are provided on the main body 1.
|
