| 摘要 |
An extension piece with a housing 12 for drain hoppers (24, fig 6), the housing comprises an upper connector 16, for connecting to a drain outlet, a lower connector 20, for installing above a drainage hopper, and a passage 22 extending between the connectors. The passage has a vertically extending conduit section, which is provided with a circumferential annular shoulder 28, which defines a plane whose surface normal is tilted with respect to the longitudinal axis of the vertical extending conduit section. The extension piece is provided with a bore hole (40, 42, fig 3) at the level of the lowest part 38 of the annular shoulder. Preferably, two separate electrodes (44, 46, fig 5) pass through the bore hole, where the ends outside the hole are connected with opposite poles of a voltage source. The electrodes may sense the flow of water and may be short circuited in a flow of water, generating acoustic, visual or digital warning signals. |
