Nozzle assembly with suck-back action

Claim 1

A unit for dispensing syrup or the like comprising an elongated manifold having a plurality of nozzle heads carried thereby at spaced intervals therealong and depending therefrom, a supply conduit connected to said manifold for feeding syrup under pressure thereto, said manifold having a common supply passage extending horizontally therealong with an inlet to which said supply conduit is connected, branch passages leading from said common supply passage at spaced intervals along its length to the respective nozzle heads, each of said branch passages comprising an upwardly-directed outlet passage leading from the common passage and having a ball-receiving valve seat at its upper end, a cylindrical ball-receiving chamber with which said upwardlydirected outlet passage connects, a ball mounted in said chamber with close tolerance but free to move vertically therein, said chamber being of a vertical extent substantially greater than the diameter of the ball and being of uniform diameter throughout its vertical extent to permit upward movement under pressure and downward movement by gravity with the ball acting substantially as a piston, and a restricted passageway leading from the upper end of said chamber to its respective nozzle head, whereby when syrup under pressure is supplied to said common passage, there is a build-up in pressure uniformly along its length until it acts simultaneously through all of said outlet passages to unseat all of the identical balls simultaneously to permit flow of syrup into the chambers and past the balls, as they rise into contact with the upper ends of said chambers, and through the restricted passages to the nozzle heads, and when the pressure in said common passage is reduced, the balls will drop downwardly simultaneously through said chambers onto said seats creating a negative pressure through said connected restricted passages to produce a suck-back of syrup at said nozzle heads.