| 摘要 |
An electric drill is provided to allow a worker to recognize easily the depth of a hole in a real time basis during drilling. An electric drill(100) includes a drill body(110) and a drill(120). The drill body includes a head(111) equipped with an electric motor, a handle(112) equipped with a switch(112a) for controlling operation of the electric motor, and a drill chuck(113) connected to an output shaft of the electric motor and exposed outwardly from the head. The drill is fixed at the drill chuck such that the drill is detachable. The head has a circumference with a connection portion(111a), and is equipped with a drilled depth measuring unit(130) including a first pipe(131), a second pipe(132), and a spring. The first pipe has one end detachably fixed at the connection portion of the head, and surrounds the drill chuck and the drill engaged with the drill chuck. The second pipe is fitted to the other end of the first pipe. The spring is arranged in the first pipe, and supports elastically the second pipe in one direction. The first pipe or the second pipe has a scale mark for marking a drilled depth. |
