Mains pressure flusher valve

Abstract

In one embodiment, a mains pressure valve has a body ( 10 ) and a main valve component ( 17 ) which is movable to effect opening and closing of the mains pressure valve. A flow controller ( 36 ) is disposed downstream of the main valve component and has a downstream end. At least one air vent ( 38 ) is provided downstream of the downstream end of the flow controller ( 36 ) and the vent is shielded from the downstream end of the flow controller ( 36 ). In another embodiment, there is a main chamber ( 12 ) within which the main valve component ( 17 ) moves, the main chamber having a control portion ( 40 ). A bypass passageway ( 13 ) has an upstream end ( 35 ) from the control portion ( 40 ) of the main chamber and a downstream end ( 46 ). A control valve ( 42 ) controls the flow through the by-pass passageway ( 13 ) to control the operation of the mains pressure valve. The downstream end ( 46 ) of the bypass passageway ( 13 ) is downstream of the flow controller ( 36 ). In a further embodiment, an upstream portion of the bypass passageway ( 13 ) is defined within a manifold ( 25 ).

1 . A mains pressure valve having a body; a main valve component which is movable to effect opening and closing of the mains pressure valve; a flow controller downstream of the main valve component, the flow controller having a downstream end; and at least one air vent downstream of the flow controller wherein the at least one vent is shielded from the downstream end of the flow controller.  
   
   
       2 . The mains pressure valve as claimed in  claim 1  further comprising an adapter nut surrounding the flow controller wherein the adapter nut incorporates a dependent annular rim to shield the at least one vent from the downstream end of the flow controller.  
   
   
       3 . The mains pressure valve as claimed in  claim 2  wherein the at least one vent is provided in a further nut threadingly engageable with the adapter nut.  
   
   
       4 . The mains pressure valve as claimed in  claim 3  wherein the further nut is in the form of a flush pipe nut adapted to connect to a flush pipe.  
   
   
       5 . The mains pressure valve as claimed in  claim 1  wherein the at least one vent is disposed level with the downstream end of the flow controller.  
   
   
       6 . The mains pressure valve as claimed in  claim 1  wherein the flow controller comprises an elastomeric duckbill valve.  
   
   
       7 . The mains pressure valve as claimed in any one of the preceding claims  claim 2  wherein the flow controller has an open mouth at an upstream end leading to converging walls which meet at the downstream end, the open mouth surrounded by a flange and the adapter nut operating to clamp the flange to the body of the mains pressure valve.  
   
   
       8 . A mains pressure valve including: 
 (a) a body defining a main chamber having an inlet for fluid, an outlet for fluid and a control portion;    (b) a main valve component located in the main chamber which is movable into and out of sealing engagement with the outlet of the main chamber and defining a passageway which provides fluid communication between the inlet and the control portion of the main chamber;    (c) a flow controller located downstream of and communicating with the outlet, the flow controller having at least one sidewall and a downstream outlet;    (d) a bypass passageway having an upstream end from the control portion of the main chamber and a downstream end;    (e) a control valve to control the flow through the by-pass passageway to control the operation of the mains pressure valve, wherein the downstream end of the bypass passageway is directed towards the at least one sidewall of the flow controller, on the downstream side of the flow controller.    
   
   
       9 . The mains pressure valve as claimed in  claim 8  wherein the flow controller is an elastomeric duckbill valve.  
   
   
       10 . The mains pressure valve as claimed in  claim 8  wherein an adapter nut surrounds the non-return valve and the adapter nut is provided with openings extending therethrough which comprise the downstream end of the bypass passageway.  
   
   
       11 . The mains pressure valve as claimed in  claim 10  wherein a recessed portion is provided in the external periphery of the adapter nut and the openings are disposed in the recessed portion.  
   
   
       12 . The mains pressure valve as claimed in  claim 10  wherein the flow controller has an open mouth at its upstream end with the at least one sidewall converging to meet at its downstream end, the open mouth surrounded by a flange and the adapter nut operating to clamp the flange to the body of the mains pressure valve.  
   
   
       13 . The mains pressure valve as claimed in  claim 10  wherein at least one vent is provided, downstream of the flow controller.  
   
   
       14 . The mains pressure valve as claimed in  claim 13  wherein the at least one vent is shielded from the downstream end of the flow controller.  
   
   
       15 . The mains pressure valve as claimed in  claim 14  wherein the adapter nut incorporates a dependent annular rim to shield the at least one vent from the downstream end of the flow controller.  
   
   
       16 . The mains pressure valve as claimed in  claim 13  wherein the at least one vent is disposed level with the downstream end of the flow controller.  
   
   
       17 . The mains pressure valve as claimed in  claim 13  wherein the at least one vent is provided in a further nut threadingly engageable with the adapter nut.  
   
   
       18 . The mains pressure valve as claimed in  claim 17  wherein the further nut is in the form of a flush pipe nut adapted to connect to a pipe.  
   
   
       19 . The mains pressure valve as claimed in  claim 8  wherein the main valve component is a piston and the passageway providing fluid communication between the inlet and the control portion of the main chamber is an internal passageway of the piston.  
   
   
       20 . The mains pressure valve as claimed in  claim 8  wherein the bypass passageway includes an upstream portion and a downstream portion, the downstream portion being incorporated into the body, there being further provided, a manifold connected to the body, the manifold defining the upstream portion of the bypass passageway including a first port fluidly connected with the control portion and a second port fluidly connected with the downstream portion of the bypass passageway.  
   
   
       21 . The mains pressure valve as claimed in  claim 20  wherein the manifold further comprises a control valve inlet and a control valve outlet.  
   
   
       22 . The mains pressure valve as claimed in  claim 21  wherein the control valve inlet and a control valve outlet are disposed on a same side of the manifold.  
   
   
       23 . The mains pressure valve as claimed in  claim 22  wherein the control valve is connected to said side of the manifold.  
   
   
       24 . The mains pressure valve as claimed in  claim 20  wherein the manifold comprises a moulded plastics body.  
   
   
       25 . A mains pressure valve including: 
 (a) a body defining a main chamber having an inlet for fluid, an outlet for fluid and a control portion;    (b) a main valve component located in the main chamber which is movable into and out of sealing engagement with the outlet of the main chamber and defining a passageway which provides fluid communication between the inlet and the control portion of the main chamber;    (c) a bypass passageway having an upstream end from the control portion of the main chamber and a downstream end which is downstream of the outlet of the main chamber, the bypass passageway having a downstream portion which is incorporated into the main body and an upstream portion;    (d) a control valve to control the flow through the by-pass passageway to control the operation of the mains pressure valve;    (e) a manifold connectable to the body, the manifold defining the upstream portion of the bypass passageway including a first port fluidly connected with the control portion and a second port fluidly connected with the downstream portion of the bypass passageway.    
   
   
       26 . The mains pressure valve as claimed in  claim 25  wherein the manifold further comprises a control valve inlet and a control valve outlet.  
   
   
       27 . The mains pressure valve as claimed in  claim 26  wherein the control valve inlet and a control valve outlet are disposed on a same side of the manifold.  
   
   
       28 . The mains pressure valve as claimed in  claim 27  wherein the control valve is connectable to said side of the manifold.  
   
   
       29 . The mains pressure valve as claimed in  claim 25  wherein the manifold comprises a moulded plastics body.  
   
   
       30 . The mains pressure valve as claimed in  claim 25  wherein the mains pressure valve is provided