| 摘要 |
<p>1. Return flow inhibitor, particularly for drinking water pipes, with an essentially cruciform housing (1), which has a lateral supply duct (2), a discharge duct (3) opposite the latter, a flow aperture (6) between the two, an outlet aperture (8) located at a spacing therebelow and connected to the discharge duct (3) by means of a downwardly-directed leakage water duct (9) as well as, above the flow aperture (6), an actuating chamber (12), continuously connected to the supply duct (2), for a closure piston (15) projecting therein with its upper actuating end, which is axially movable against a spring force under the action of the supply water pressure and which thereby causes the flow opening (6) and the outlet aperture (8) selectively to close or open, characterized in that the closure piston (15) is constructed as a stepped piston, in its lower region (15') controlling the flow and outlet apertures (6, 8), and is connected above with an actuating piston (14) sealingly guided in the actuating chamber (12) spatially separated from the supply duct (2) and both piston (14, 15) are traversed longitudinally by a sealing and abutment stem (18) fixed to the housing, which, with the piston (14, 15) surrounding it, defines a narrow bleed duct (22) which extends between the actuating chamber (12) and the leakage water duct (9) and is closable in the two end positions of the closure piston (15).</p> |
