| 摘要 |
PURPOSE:To provide possibility of driving either of the drive mechanisms selectively without particular operation for changing-over by furnishing a drive mechanism, which retracts when a drive nut in meshing with a feed screw part on the actuator shaft is rotated, and a drive mechanism to rotate this actuator shaft. CONSTITUTION:If motor 7 of No.1 drive mechanism 3 is rotated while NO.2 drive mechanism 11 is at a standstill, the torque is transmitted to a drive nut 4, which is thus put in rotation. At this time, the actuator shaft 2 is hindered from rotating by the worm 14 part of No.2 drive mechanism 11, and makes a reciprocative motion in the vertical direction without revolutions. If, on the other hand, the manual handle 13 of No.2 drive mechanism 11 is rotated while No.1 drive mechanism 3 is at a standstill, the torque is transmitted to the actuator shaft 2, which is thus put in rotation. |
