FLUID CONTROL VALVES Russian patent published in 2013 - IPC B65D47/20 B29C45/00 

FIELD: transport.

SUBSTANCE: fluid control valve comprises valve plate 26 made of elastic polymer material with, at least, one elongated fracture made therein. Said fracture makes, at least, one valve flap 28 made integral with valve plate. Note that flap edge confined by fracture is not jointed with adjacent material of valve plate. Valve flap 28 may be driven by pressure from closed position whereat adjacent edge areas of fracture make dense seal into open position whereat said areas are spaced apart to allow fluid flow through valve element. Polymer material represents polyolefin. Proposed method comprises feeding hot fluid material into casting cavity. Said cavity is confined on one side by mould first part and, on the other side, by mould second moving part. Said moving part comprises relatively movable split element. Forming one or several first elongated recesses on valve element surface to confine one or several first lines of decreased thickness, cooling and hardening the material, extending split element relative to valve element for its stretching and decreasing its thickness, and subsequent fracture along said first lines of decreased thickness to form valve flap and withdrawal of valve element from casting cavity.

EFFECT: fast and low-cost process.

7 cl, 9 dwg