HANEVENTIL MED HAEVERTMODVIRKENDE INDRETNING TIL FORHINDRING AF TILBAGELOEB

摘要

A cock valve 10 comprises a ball valve 28 which is arranged in a valve chamber 18. The ball valve 28 has a number of openings 46 which are arranged with a mutual spacing around an adjusting spindle 32 which extends through an opening 60 in a cap assembly 48 belonging to the valve housing 16. A non-return valve 66 is formed in the hollow interior 62 of the ball valve and comprises a plate section 70 which is provided with a flap valve 78. A shield, which is formed by a cylindrical wall 80 which extends downwards from the plate section 70, and a snap ring 84, which is fitted at the lower end of the cylindrical wall, protect the flap valve against powerful turbulence in the water. In the event of negative pressure in the delivery inlet, the flap valve 78 opens, in which way air is forced through a passage 64 formed by the openings 46 and the auxiliary opening 60 and the hollow interior 62 of the ball valve located in the valve chamber 18.