A water-level control unit with a downwardly hanging hinged lower flap portion of a valve element and a floating body connected thereto

Abstract

A water-level control unit includes a housing with a flow channel. A valve element is positioned rotatable around a hinge axis inside the flow channel to close off a lower section of the flow channel while dividing it in a first upstream side and a second downstream side. The hinge axis is provided at a height above a bottom of the flow channel. The valve element includes a lower flap portion that in a closed position hangs down from the hinge axis. A floating body is provided at and connected to a side of the lower flap portion for moving the valve element from its closed towards an open position in dependence of a rising level of water at the first upstream side in the flow channel.

1 . A water-level control unit configured for installation inside or onto a culvert, ditch or outlet of a drainage pipe and/or system of a water collecting surface area, the unit comprising:
 a housing that delimits a flow channel that has a lower section and an upper section;   a valve element that is positioned rotatable around a hinge axis inside the flow channel between a closed and an open position, wherein the valve element is configured to in its closed position close off the lower section of the flow channel while dividing the flow channel in a first upstream side and a second downstream side, and to in its open position open the lower section; and   a floating body for moving the valve element in dependence of a rising level of water,   wherein the hinge axis of the valve element is provided at a height spaced above a bottom of the flow channel,   wherein the valve element comprises a lower flap portion that in its closed position hangs down from the hinge axis,   wherein the floating body is provided at and connected to a side of the lower flap portion at a height position in between the hinge axis and the bottom of the flow channel,   wherein the lower flap portion, that in its closed position hangs down from the hinge axis, is rotatable around the hinge axis towards the first upstream side to rotate open from its closed position into its open position, and   wherein the floating body is configured for moving the valve element from its closed position towards its open position in dependence of a rising level of water at the first upstream side in the flow channel.   
     
     
         2 . The water-level control unit according to  claim 1 , wherein the floating body is configured for starting to pull the lower flap portion towards the first upstream side from its closed position into its open position due to buoyancy forces starting to act on the floating body when a level of water is reached at the first upstream side that corresponds to the height position at which the floating body is provided, while rotating the lower flap portion through the level of water at the first upstream side and opening up the lower section of the flow channel for the water to flow away towards the second downstream side. 
     
     
         3 . The water-level control unit according to  claim 1 , wherein the floating body is provided at and connected to the first upstream side of the lower flap portion at the height position in between the hinge axis and the bottom of the flow channel. 
     
     
         4 . The water-level control unit according to  claim 1 , wherein a primary height-adjustable connection system is provided between the floating body and the lower flap portion, which primary height-adjustable connection system is configured for varying the level of water to be reached at the first upstream side for the floating body to start pulling the lower flap portion towards the first upstream side from its closed position into its open position. 
     
     
         5 . The water-level control unit according to  claim 4 , wherein the primary height-adjustable connection system comprises complementary mounting means that are fixedly mountable against the lower flap portion while extending perpendicular to the hinge axis, and that are configured to mount the floating body at different height positions against the lower flap portion in between the hinge axis and the bottom of the flow channel. 
     
     
         6 . The water-level control unit according to  claim 1 , wherein
 the valve element is configured to leave open at least part of the upper section of the flow channel in its closed position.   
     
     
         7 . The water-level control unit according to  claim 1 , wherein a partition wall is provided between the lower and upper section, which partition wall projects towards the first upstream side, and wherein the partition wall is configured for the floating body and/or lower flap portion to abut against in the open position. 
     
     
         8 . The water-level control unit according to  claim 1 , wherein the hinge axis extends between the lower section and upper section. 
     
     
         9 . The water-level control unit according to  claim 8 , wherein the valve element further comprises an upper flap portion that in its closed position projects upwardly from the hinge axis. 
     
     
         10 . The water-level control unit according to  claim 1 , wherein a secondary height-adjustable connection system is provided between the valve element and the hinge axis. 
     
     
         11 . The water-level control unit according to  claim 1 , wherein the housing comprises a holding/blocking arrangement, in particular an inwardly projecting abutment, more in particular forming a valve seat, at the lower section of the flow channel and configured for the lower flap portion to be held by and/or lie against in its closed position. 
     
     
         12 . The water-level control unit according to  claim 11 , wherein the holding/blocking arrangement, in particular said inwardly projecting abutment, is positioned at such a distance from the hinge axis that the lower flap portion in its closed position hangs down obliquely angled towards the first upstream side. 
     
     
         13 . The water-level control unit according to  claim 1 , wherein the housing comprises an outer blocking or sealing arrangement that is configured to fit blocking or sealing inside a culvert, ditch or outlet of a pipe. 
     
     
         14 . The water-level control unit according to  claim 1 , wherein the housing comprises an inner blocking or sealing arrangement that is configured to fit sealing onto a culvert, ditch or outlet of a pipe. 
     
     
         15 . The water-level control unit according to  claim 1 , wherein the flow channel at the first and/or second downstream side is covered by a filter and/or grating. 
     
     
         16 . An assembly of a water-level control unit according to  claim 1  and a culvert, ditch or outlet of a drainage pipe and/or system of a water collecting surface area. 
     
     
         17 . A method for controlling a water-level by means of a water-level control unit according to  claim 1 , comprising the steps:
 installing the unit inside or onto a culvert, ditch or outlet of a drainage pipe and/or system of a water collecting surface area;   positioning the floating body at a height position in between the hinge axis and the bottom of the flow channel that corresponds to an aimed level of water that needs to be reached at the first upstream side before starting to pull the lower flap portion through the level of water towards the first upstream side from its closed position into its open position due to buoyancy forces starting to act on the floating body; and   passively and automatically controlling the water-level by means of:   each time the level of water at the first upstream side of the lower flap portion reaches the height position of the floating body, have the floating body pull the lower flap portion through the level of water towards the first upstream side from its closed position into its open position due to buoyancy forces acting on the floating body, while opening up at least the lower section of the flow channel for the water to flow away towards the second downstream side; and   each time the level of water at the first upstream side of the lower flap portion has dropped again to underneath the height position of the floating body, have the lower flap portion move back again from its open position into its closed position due to the buoyancy forces on the floating body dropping again, while closing off at least the lower section of the flow channel for the water to be blocked again at the first upstream side draining away towards the second downstream side.