| 摘要 |
A closure element with a pipe housing which can be incorporated in a pipeline and a butterfly flap, for which are provided a drive shaft passing through the housing and a seating in the housing whereby, arranged on the drive shaft (10), is an annular disc (4) with loose bearings (9), and the valve flap (3) is guided in the annular disc (4), and is linked with the drive shaft by a gear unit (22, 23) which is restricted when the valve flap (3) pivots, and serves to apply the valve flap (3) against its seating (32). The closure element is characterized by the fact that the gear unit (22, 23) raises the valve flap (3) axially from the seating (32) when the drive shaft (10) turns back, until the flap is supported on the annular disc (4), and by the fact that the gear unit (22, 23) forms the connection between the valve flap (3) and the drive shaft, whereby the valve flap (3) bears on the annular disc (4). |
