| 摘要 |
A closure apparatus ( 1 ) for covering an opening ( 2 ) in a storage tank comprising: (a) a connector to connect the apparatus to the silo in the proximity of the opening ( 2 ); (b) a cover ( 10 ) to cover the opening ( 2 ), said cover having a projection ( 11 ) forming a leading edge of the cover ( 10 ), (c) an elongate guide member having a guide surface ( 13 a, 14 a), the cover ( 10 ) being slidingly engaged with the guide member and movable along the guide surface ( 13 a, 14 a) from a first position adjacent the opening ( 2 ) to a second position covering the opening ( 2 ); and (d) an actuator ( 4,5 ) to move the cover between the first position and the second position; wherein the projection ( 11 ) removes debris on the guide surface ( 13 a, 14 a) during movement between the first position and the second position. |
