| 摘要 |
<p>The present invention relates to a hybrid excavator on which is mounted an electro-hydraulic actuator for quickly stopping a working device being operated at high speed during work such as pipe laying. The hybrid excavator on which the electro-hydraulic actuator is mounted according to the present invention is characterized in that it comprises: a first detection sensor for detecting an RCV-manipulated quantity; a second detection sensor for detecting the rotational speed of an electric motor; a hydraulic pump-motor connected to the electric motor; a hydraulic cylinder connected to the hydraulic pump-motor; first and second hydraulic valves installed in first and second passages, respectively, between the hydraulic pump-motor and the hydraulic cylinder; a third hydraulic valve for compensating for or bypassing a flow rate when a difference in the flow rate occurs due to a difference between the cross-sectional areas of a large chamber and a small chamber of the hydraulic cylinder when the hydraulic pump-motor is converted between forward or backward rotation; and a controller for receiving an RCV-manipulation signal from the first detection sensor and the rotational speed of the electric motor from the second detection sensor to compare the received values to data of previously stored working conditions, to output a control signal for switching the first and second hydraulic valves, and to block a working fluid from returning into the hydraulic cylinder, so as to thereby quickly stop the working device.</p> |
