Liquid distribution unit
A liquid distribution unit, for use in a liquid distribution system designed for saving liquid and thermal energy. It comprises and inlet manifold (FL) with a number of branch connections (CI, C 2 ) for connection, in use, with associated feeding conduits (FC 1 , FC 2 ) and liquid tap units. The inlet manifold device has an inlet end (IE) for joint connection, in use, with a liquid source (LS). Each branch connection has an associated control valve (CV 1 , CV 2 ) for selective communication, in use, between the liquid source and an associated one of the feeding conduits. Each branch connection is also provided with an additional branch connection located downstream in relation to the associated control valve, as seen when the liquid is refilled into the feeding conduit, and having an associated, separate liquid evacuation valve (EV 1 , EV 2 ) and an outlet end (OE 1 , OE 2 ). The outlet ends of the additional branch connections are jointly connectable to an evacuation liquid pump (EP).
1. A liquid distribution system, provided with a liquid distribution unit and having two or more feeding conduits connected to a central liquid source and each being connected at its far end with an associated liquid tap unit, the liquid distribution unit enabling a selective feeding of liquid from said central liquid source to a desired number of the liquid tap units, said liquid distribution unit comprising:
an inlet manifold device having an inlet end connected to said central liquid source and an outlet end with at least two branch connections;
a feeding pipe connection extending from each of the at least two branch connections;
a control valve in each said feeding pipe connection, each control valve being open when feeding liquid from said central liquid source to an associated liquid tap unit;
a junction at a downstream end of each said control valve, said junction being connected to a respective one of said two or more feeding conduits;
said junction also being connected to an additional branch connection adjoining to a respective evacuation valve, each said evacuation valve being open or closed when the associated control valve is closed, and each said evacuation valve being closed when the associated control valve is open,
wherein each said evacuation valve communicates with a branch outlet, each said branch outlet is connected to an outlet manifold device, said outlet manifold device has a single outlet being connected to an evacuation liquid pump, and said evacuation liquid pump has an outlet that is connected to said central liquid source for recirculating liquid backwards from at least one of said two or more feeding conduits after completion of a tapping operation in at least one associated liquid tap unit.
2. The liquid distribution system defined in claim 1 , wherein said control valves and said associated evacuating valves are operable in such a way that at least one of said feeding conduits is connected via an associated control valve to said central liquid source, while at least one other feeding conduit is simultaneously connected, via an associated evacuating valve to said evacuation liquid pump.
3. The liquid distribution system defined in claim 2 , wherein said control valves and said associated evacuation valves are also operable in such a way that at least one of said feeding conduits is disconnected from said central liquid source as well as from said evacuation liquid pump.
4. The liquid distribution system defined in claim 1 , wherein the inlet manifold device and the outlet manifold device are elongated and mutually parallel so as to form a module together with said control valves and said evacuation valves.
5. The liquid distribution system defined in claim 1 , wherein said control valves and said associated evacuation valves are electromagnetic valves configured to be connected to an electronic control unit liquid distribution system.
6. The liquid distribution system defined in claim 5 , wherein each of said evacuation valve is adapted to become activated via said electronic control unit.
7. The liquid distribution system defined in claim 5 , wherein said electronic control unit forms a part of the liquid distribution unit and wherein said electronic control unit is also connected to a level sensor in said feeding conduit adjacent to said associated feeding pipe connection, said level sensor also forming a part of the liquid distribution unit.
8. The liquid distribution system defined in claim 1 , wherein each said feeding conduit is connected via a non-return valve to said liquid tap unit, and
wherein said central liquid source is operative to provide a driving pressure of 2 to 5 bars overpressure in relation to an ambient air pressure prevailing outside said liquid distribution system, when the associated control valve is open, at the downstream side of said control valve and in each associated feeding conduit.
9. The liquid distribution system defined in claim 1 , wherein said feeding conduits are 5 to 30 m long, measured from said associated control valve to said liquid tap unit.
10. The liquid distribution system defined in claim 1 , comprising at least one module including:
a part of said inlet manifold device,
at least two of said branch connections,
at least two of said feeding pipe connections,
at least two of said additional branch connections,
at least two of said associated evacuation valves, and
at least one of said branch outlets being connected via said outlet manifold device to said evacuation liquid pump.
11. The liquid distribution system defined in claim 1 , wherein said evacuation liquid pump is adapted to reduce the pressure, during the backwards recirculation of liquid after a tapping operation, down to a lowermost pressure level of 20-80% of an ambient air pressure prevailing outside the liquid distribution system.
12. A liquid distribution unit for selective feeding of liquid from a central liquid source to a desired number of liquid tap units, the liquid distribution unit comprising:
an inlet manifold device having an inlet end configured to connect to the central liquid source and an outlet end with at least two branch connections;
a feeding pipe connection extending from each of the at least two branch connections;
a control valve in each of the feeding pipe connections, each control valve configured to be open when feeding liquid from the central liquid source to an associated liquid tap unit; and
a junction at a downstream end of each of the control valves, each junction configured to be connected to a feeding conduit and to an additional branch connection adjoining to a respective evacuation valve,
wherein each evacuation valve is open or closed when the associated control valve is closed, and each evacuation valve is closed when the associated control valve is open,
wherein each evacuation valve communicates with a branch outlet that is connected to an outlet manifold device having a single outlet being connected to an evacuation liquid pump, and
wherein the evacuation liquid pump has an outlet that is configured to be connected to the central liquid source for recirculating liquid backwards from at least one of the feeding conduits after completion of a tapping operation in at least one associated liquid tap unit.
13. The liquid distribution system defined in claim 1 , further comprising an electronic control unit that forms a part of the liquid distribution system and is configured to control operation of the liquid distribution unit.
14. The liquid distribution system defined in claim 13 , wherein the electronic control unit forms a part of the liquid distribution unit.