摘要 |
<p>In a non-drip valve for a fluid flow line having a vacuum unit comprising supply chamber, a discharge chamber and a vacuum chamber connected to the dischargbe chamber to withdraw fluid therefrom when the forward flow is arrested, and improved control valve controlling the flow of fluid from a source to the supply chamber comprising a ball element operable between alternate positions, one of which admits fluid from the source of supply to the supply chamber and blocks the flow of fluid from the supply chamber to a return line, and the other of which blocks flow of fluids from the supply source to the supply chamber and simultaneously affords flow of fluid from the supply chamber to the return line, the position of said ball element being controlled by the armature of a solenoid.</p> |