Blast aerator

A blast aerator comprising:

• a generally cylindrical, rigid tank having an axis, and a front end fitted with a blast discharge opening coaxially aligned with respect to said axis;
• a rigid, elongated, tubular, blast discharge pipe adapted to be coaxially secured and aligned within said tank, said pipe having a front output end, a rear end positioned interiorly of said tank, a counterbored, internal front shoulder seat, and a predetermined intermediate internal diameter;
• a piston seat assembly coaxially positioned within said blast discharge pipe in abutting relation with respect to said internal shoulder, said seat assembly including a rear, chamfered seat;
• a resilient, generally cylindrical, dual diameter piston coaxially disposed within said blast discharge pipe and axially displaceable between an aerator tank fill position and an aerator tank exhaust position;
• an intermediate portion of said piston having a diameter substantially equal to said blast output pipe predetermined intermediate diameter, and a front portion of said piston having a diameter less than said piston intermediate diameter portion and terminating in a front, chamfered portion adapted to matingly engage said piston seat assembly chamfered seat when said piston assumes aid aerator fill position;
• said piston including a shoulder defined between said intermediate diameter portion thereof and said reduced diameter portion thereof, said shoulder forming a working surface against which tank pressure may urge said piston toward said rear end of said blast discharge pipe in response to venting of said cavity;
• vent means defined in said blast discharge pipe for outputting air temporarily stored within said tank through said blast discharge pipe front ouptut end in response to movement of said piston to said aerator tank exhaust position;
• end cap means adapted to be coaxially, sealingly coupled to said blast discharge pipe rear end for limiting rearward axial displacement of said piston, the end cap means operable to define a sealed cavity between it and said piston at the rear of said blast discharge pipe;
• and,
• valve control means in fluid flow communiation with said cavity for filling said cavity and thus said tank and for subsequently initiating an output blast by venting said cavity, said valve control means comprising:
• first air injection fitting means coupled to said end cap means for injecting air into said cavity rearwardly of said piston whereby to pressurize said cavity and move said piston into sealing engagement with said chamfered seat;
• check valve means coupled to said end cap in fluid flow communciation with said cavity for pressurizing the interior of said tank in response to pressurization of said cavity;
• and,
• solenoid valve means for first actuating said air injection fitting means whereby to fill said tank through said check valve means and then depressurizing said cavity at a preselected time whereby to suddenly exhaust said tank through said output pipe in response to resultant rearward displacement of said dual diameter piston.