| 摘要 |
<p>Cleaning apparatus of the type including a cleaning head for cleaning submerged surfaces and a flapper valve for moving the head relative to the surface by oscillation thereof. An annular flexible disc located at the inlet end of the suction head surrounds a central opening below the flexible disc and at least one transverse inlet opening to the passage through the suction head is located above and adjacent the flexible disc. The transverse inlet opening is substantially symmetrical about the direction of movement of the head and faces in the general direction towards which the head moves in operation. An upper member held in spaced relationship relative to the disc may be provided to define a flow path between it and the disc towards the transverse inlet opening.</p> |
