Anti-siphon device for a flush valve

摘要

An anti-siphon device for a flush valve having an air-inlet sealing diaphragm, a diaphragm bracket with an air inlet, a flex sleeve, a venting bracket, and an offsetting spring. The deformation power of the air-inlet sealing diaphragm is comparatively small. When compared with existing anti-siphon reflux devices, this anti-siphon device has a very low current pressure loss and can prevent leaking. When the anti-siphon device is applied in heating and plumbing devices, such as a flush valve, the current pressure can be retained and thus satisfactory flush effect is achieved.

主权项

1. An anti-siphon device comprising:
a fluid passageway having a fluid inlet and a fluid outlet; at least one air inlet; a venting bracket fixedly located within the fluid passageway, the venting bracket providing a first portion of an air passage which is in fluid communication with the at least one air inlet; a diaphragm bracket in sliding engagement with the venting bracket which provides a second portion of the air passage which is in fluid communication with the at least one air inlet through the first portion of the air passage; a resiliently deformable diaphragm biasedly mounted on the diaphragm bracket; at least one air opening provided in the diaphragm bracket adjacent to the diaphragm; and a flex sleeve disposed between the venting bracket and the diaphragm bracket; wherein in a sealed position, no fluid flows through the fluid inlet, the diaphragm is disposed against a fluid inlet seal surface, and fluid communication is open through at least one air opening in the diaphragm bracket between the fluid outlet and the at least one air inlet; wherein in a unsealed position, the diaphragm is disposed away from the fluid inlet seal surface and fluid flows through the fluid inlet, and the diaphragm is deformed to restrict fluid communication through at least one air opening in the diaphragm bracket between the fluid outlet and the at least one air inlet.