Proportional flow control dispensing gun

Proportional flow fluid dispensing apparatus comprising:

• a piston;
• a flow control valve means having a valve stem operably connected to said piston for controlling the flow of the fluid;
• a passageway for pressurized air opening to one side of the piston;
• an air valve means for controlling the flow of pressurized air into said passageway;
• a direct mechanical spring feedback means;
• a linear effort electric torquemotor means operably disposed in a position between said mechanical spring feedback means and said air valve means for directly stroking said air valve means, said direct mechanical spring feedback means being operably disposed between said piston and said linear torquemotor means for positioning said air valve means to block said passageway after said valve stem has been moved to a position linearly corresponding to the force exerted by said torquemotor,
• wherein said air valve means comprises a valve body and a balanced, three land spool reciprocally mounted in said valve body, said valve body having an exhaust port, a supply port and a load port, the outermost of such lands being directly exposed on outwardly facing sides to atmospheric pressure, and the innermost of such lands adjacent said load port, said innermost land selectively sealing such load port and wherein one face of said innermost land is directly exposed to said supply port and one face of said innermost land is directly exposed to said exhaust port.