Check valve

摘要

A check valve in a spray nozzle assembly includes a body adapted at one end to receive a liquid source and at the other end to engage with a spray nozzle and having a bore therethrough, the bore having a first section adjacent the upstream end of the body, the first section having a smaller diameter than a second downstream section such that a valve seat is provided at the junction of these components. A valve assembly is located generally in the second section and has a valve member with a generally curved end directed towards the seat and bias means to normally hold the member against the seat until the pressure at the inlet reaches a pre-determined minimum. A releasable retaining means retains the check valve assembly within its body such that a unitary check valve is provided whereby in use of the check valve in a spray nozzle assembly, the check valve can be removed from the spray nozzle without disrupting the check valve.