Patent ID: 11060634

Abstract:
There is described a media metering valve (18) comprising a main body (21) having a media inlet (26), a central bore (24) extending through the main body (21), said media inlet (26) being in communication with the central bore (24) and a chamber (28) formed in communication with the central bore (24). A base member (23) attachable to the main body (21), the base member (23) having a central passage (27) extending therethrough, said central passage (27) extending orthogonal to the central bore (24) of the main body and being in fluid communication with said central bore (24). A cap member (22) is mounted to the main body (21) so as to substantially enclose the chamber (28). A piston (30) is movably mounted within the chamber (28). The piston (30) having a plunger member (31) rigidly connected thereto, the plunger member (31) being positioned within the central bore (24) to move in a reciprocal manner therein under action of the piston (30). A bypass member (40) is sealingly mounted about said plunger (31) member to provide a seal between the chamber (28) and the central bore (24). Pressurised air is delivered to said central passage (27) of the base member (23) to receive media delivered from the media inlet (26) when the plunger member (31) is in an open position. Wherein, upon the seal between the chamber (28) and the central bore (24) becoming compromised the bypass member (40) functions to equalise air pressure between the chamber (28) and the central bore (24) to minimise the egress of air and media from the central bore (24) to the chamber (28).