Pneumatic pressure control valve

A signal responsive fluid pressure control valve for providing a controllable output pressure from first and second input pressure sources proportional to an electrical control signal with minimum fluid mass flow comprising

• a valve housing including a controlled pressure chamber,
• a first nozzle connected with said first pressure source and extending into said chamber,
• a second nozzle connected with said second pressure source and extending into said chamber,
• first and second flapper means adjacent said first and second nozzles respectively and defining first and second gaps therebetween, said flapper means being adapted to be moved relative to said nozzles to increase and decrease said gaps and thereby control the resultant pressure within said chamber in accordance with the relative positions of said flapper means,
• electric torque motor and armature means adapted to move said flapper means in accordance with said electrical control signal, and
• resilient means coupling each of said flapper means with said housing and with said armature means, said resilient means providing simultaneous movement of both of said flapper means by said armature means to simultaneously increase one of said gaps and decrease the other, and providing independent movement of one of said flapper means by said armature means when the gap defined by the other thereof is decreased to zero.