| 摘要 |
PURPOSE:To improve the environment of working by working an alarm buzzer to be interlocked with the operation of a slewing base only for a fixed period of time from immediately beginning of the startup of the slewing base. CONSTITUTION:An operating lever 11 is connected in an interlocked manner to a valve 10 to normaly or reversely switch and stop an operation motor 3 for driving a slewing base 2. Limit switches 12A and 12B to detect each of normal and reverse operations of the lever 11 from immediately after the beginning of the operation of the lever 11 is provided to the lever 11, and a differential path 13 to send out the signal of working command only for a fixed period of time on the basis of information from the lever 11 is also provided. A solenoid switch 14 to be operated by signals from the circuit 13 is provided in parallel with a manually operating switch 15 in the power source circuit 16 of the alarm buzzer 9. Since the buzzer 9 is operated only for a fixed period of time from immediately before the beginning of startup of the base 2, the continuous sounding of the buzzer 9 can be prevented. |
