AUTOMATIC VIBRATION METHOD OF HYDRAULIC EXCAVATOR AND AUTOMATIC VIBRATOR

PURPOSE:To improve work efficiency by using an electric - hydraulic control circuit for making an automatic repeating control and making it possible to vary amplitude and frequency of a working actuator according to a working form. CONSTITUTION:An automatic vibration mode switch 6 is turned ON, and repeating control signals (ja) and (ib) selected by a vibration mode switch 4 and a wording mode switch 5 are inputted to a controller 3. Voltage signals KBO, KBU and KA of an output pulse from the controller 3 are inputted to a controller 7, and finally current signals 7e and 7f are outputted to solenoids 8 and 9 to open electric control hydraulic valves 10-13. In addition, a moving direction and speed of a piston rod of a working machine cylinder 15 such as a working actuator is controlled on a designated amplitude and frequency by the vibration mode switch 4. Accordingly to the constitution, work efficiency can be improved.