Force balanced two-way control valve.

摘要

A flapper nozzle two-way control valve for controlling large flows of fluid under pressure from a source to a load by displacement of the flapper (20) with respect to the outlet orifice (24) of a nozzle (22). The forces developed by the fluid impinging upon the flapper are balanced by counterforces applied to the opposite side (42) of the flapper. Such counterforces are developed by fluid of substantially identical area impinging the flapper or by utilization of a mechanical apparatus such as a ball (48) which engages the surface of the flapper in response to application of fluid under pressure thereto.