| 摘要 |
<p>A mining machine includes a boom, a cutter head, a valve, and an actuator. The boom defines an internal chamber and includes a first end coupled to a frame, a second end, and an opening in fluid communication with the internal chamber. The cutter head includes a plurality of cutting bits and is supported on the second end of the boom. The valve is coupled to the boom and is movable between a closed position in which the opening is covered and an open position in which the opening is at least partially uncovered. The actuator is coupled to the valve to selectively move the valve between the closed position and the opened position.</p> |
