| 摘要 |
PURPOSE:To enable exchange of a rotary grinding stone without suspending a cutting work by a method wherein rotary grinding stones are respectively mounted to a pair of rockable arms, and a switching transmission means adapt ed to switch the rotation power of a motor to the one grinding stone for trans mission is provided. CONSTITUTION:With the one cylinder 58a expanded, an arm 11a is hung down, and the one rotary grinding stone 37a is set in a steel cutting position. With a motor 7 run, a drive force thereof is transmitted through a clutch gear to a rotary output shaft to rotate the one rotary grinding stone 37a, and a steel 3 is cut by means of the rotary grinding stone 37a. In this case, the other arm 11b is lifted up through contraction of a cylinder 58b, and the other rotary grinding stone 37b is exchanged where necessary. When the one rotary grinding stone 37a is worn, the one arm 11a is lifted up, the other arm 11b is hung down, and the other rotary grinding stone 37b is set in a cutting position. With this state, the drive force of the motor 7 is transmitted through the clutch gear to the rotary output shaft to rotate the rotary grindings tone 37b. |
