Connection fitting

Abstract

The present invention relates to a connection fitting for the connection of a ring with at least one consumer to a storey or rising main branch with inlet and outlet openings ( 2, 4 ) which can be connected to the branch and an intervening merge opening ( 34 ) for the ring main which is preceded in the flow direction (S) by a cross-section constriction ( 16 ). The present invention also relates to a water pipe system with at least one storey or rising main branch to which several ring mains are connected via separation and merge openings and a cross-section constriction provided between the separation and merge openings of the assigned ring main in the branch. The object of the present invention is to specify a connection fitting which leads to improved flow characteristics in the region of the ring main assigned to the connection fitting and to provide a water pipe system which fulfils the practical requirements in an improved manner. With this invention the object is solved by suggesting a connection fitting and a water pipe system of the prior known type, which are characterised in that they comprise means ( 12, 28 ) for varying the passage area of the cross-section constriction (V).

1 . Connection fitting for a water pipe system for the connection of a ring main with at least one consumer to a storey or rising main branch with inlet and outlet openings which can be connected to the branch, an intervening merge opening for the ring main which is preceded in the flow direction by a cross-section constriction acting as a Venturi nozzle, and means for varying a passage area of the cross-section constriction in response of a pressure difference generated by the Venturi effect from the cross-section constriction. 
     
     
         2 . The connection fitting of  claim 1 , wherein the means for varying comprises a movable throttle element, which can move relative to the cross-section constriction (V). 
     
     
         3 . The connection fitting of  claim 1 , wherein when the means for varying a passage area contacts the cross-section constriction, a leakage flow (L) through the cross-section constriction is possible. 
     
     
         4 . The connection fitting of  claim 1 , wherein the cross-section constriction forms a conical surface and the means form a conical counter surface that interacts with the conical surface. 
     
     
         5 . The connection fitting of  claim 1 , wherein the means is held by a spring element against the cross-section constriction. 
     
     
         6 . The connection fitting of  claim 1 , wherein the means for varying further comprises a guide element which movably holds the throttle element. 
     
     
         7 . The connection fitting of  claim 6 , wherein the guide element and the means are coaxial and are aligned along a longitudinal axis of the branch. 
     
     
         8 . The connection fitting of  claim 7 , wherein the guide element is formed as part of an insertion part which forms the cross-section constriction. 
     
     
         9 . The connection fitting of  claim 8 , wherein an external circumference of the insertion part comprises locking means for holding the insertion part in the housing of the connection fitting. 
     
     
         10 . The connection fitting of  claim 9 , wherein the locking means is formed by a plurality of latching lugs, form one another in a circumferential direction of the insertion part, and wherein latching grooves are formed on an internal circumferential surface of the housing to engage the latching lugs. 
     
     
         11 . The connection fitting of  claim 6 , wherein the guide element covers the merge opening, and wherein an outer wall of the guide element has at least one ring main flow outlet. 
     
     
         12 . The connection fitting of  claim 1 , wherein the means have a through hole running in a longitudinal direction, through which an inner pipe can be passed. 
     
     
         13 . The connection fitting of  claim 12 , further comprising an inner pipe that movably guides the means. 
     
     
         14 . The connection fitting of  claim 12 , wherein the insertion part comprises a plurality of supporting ridges on a face-side end, the ridges defining an external circumferential surface of the insertion part and extending in the axial direction, and the ridges forming a funnel shape. 
     
     
         15 . The connection fitting of  claim 1 , wherein when there is a pressure difference (Δp) between the inlet and outlet separation and merge openings of (i) about 20 millibar or less or (ii) of about 30 millibar or more, the pressure difference (Δp) has the following relationship:
   Δ p˜Q   2 ,
 
 where Q is the flow rate in the ring main. 
 
     
     
         16 . The connection fitting of  claim 1 , wherein when there is a pressure difference (Δp) between the inlet and outlet openings of about 30 mbar or less or of about 20 mbar and more, the pressure difference (Δp) has the following relationship:
   Δ p˜Q   n ,
 
 where 0.6≦n≦1, and Q is the flow rate in the ring main. 
 
     
     
         17 . The connection fitting of  claim 16 , wherein n=⅔. 
     
     
         18 . A water pipe system having a main branch to which a ring main is connected via a separation opening and a merge opening, wherein a cross-section constriction is provided between the separation opening and the merge opening, and comprising means for varying a passage area of the cross-section constriction.