High-viscosity volume balancing mixing head

Abstract

A dispensing gun for mixing, then pouring or spraying reactive components, many of which have high viscosity. The gun consists of a material or mixing head or body having a plurality of chambers or canals connecting input ports through passageways and valves in close coupled relationship to a mixing chamber. Valves for purging or flushing the mixer body are also closely coupled to the input parts and mixing chamber. A rotatable mixing grid and mixing sleeve are removably retained in the mixing chamber and can be easily removed for adapting the gun for use with a static or motionless mixer. A high torque pneumatic motor located on the mixer center line drives the mixer grid in the mixing chamber. The mixer body has three or more material inlets, four valves, and a connection for the pneumatic motor all closely coupled to the mixing chamber. The arrangement of valves and pneumatic motor connections permits the device to be easily adapted for completely automatic operation. The trigger for the gun provides built-in lead and lag adjustments for materials having different viscosities and/or pressures. The purging system provides a connection for a coaxial hose, permitting air and/or solvent flushing of the entire mixing gun body. The nozzle is easily replaceable to permit pour or spray configuration.