| 摘要 |
<p>A rotary shaft of a hydraulic machine has a collar projecting radially outwardly therefrom. The rotary shaft and the collar are encased by a casing which carries a seal ring to be pressed against an axial end surface of the collar to form a fluid-tight seal therebetween. The axial end surface of the collar slidingly contacting with the seal ring is provided with a plurality of radial grooves extending from the central portion of the collar to the outer peripheral edge thereof. As the rotary shaft rotates at a high speed, a centrifugal force is generated to separate sand and soil particles from the water within the radial grooves.</p> |
