Sealant spray applicator system and method employing same

A method for applying liquid sealant in holes of a structural member prior to installing fasteners in said holes, which comprises:

• providing a sealant applicator controller and a spray gun having a spray nozzle positioned adjacent to but out of contact with said holes, a first timer activated by said controller to permit high pressure air to blow through the spray gun, and a second timer activated through said controller to permit a flow of liquid sealant under pressure through said spray gun,
• passing said high pressure air to said nozzle for a first predetermined period of time set by said first timer, and passing said liquid sealant to said nozzle for a second predetermined period of time set by said second timer, said first predetermined time period being longer than said second predetermined time period,
• mixing said high pressure air and liquid sealant in said nozzle to atomize same,
• spraying a controlled amount of the resultant atomized air-liquid sealant mixture into the holes and depositing liquid sealant therein, and
• after said second predetermined time period has passed and liquid sealant ceases to flow to said nozzle, impinging the high pressure air stream alone for the remainder of said first predetermined time period from said nozzle onto the deposited liquid sealant to spread the sealant out and produce a thin layer of said sealant in said holes, and prevent dripping.

A system for applying liquid sealant in holes of a structural member, which comprises:

• a spray gun having a spray nozzle,
• means forming separate air and liquid sealant paths to said spray nozzle for mixing said air and sealant to form an air-sealant spray adapted to be directed into said holes,
• a sealant applicator controller,
• a source of high pressure,
• a first timer actuated by said controller,
• a first valve means actuated by said first timer to permit said high pressure air to flow to said spray nozzle,
• a source of liquid sealant,
• a second timer activated by said controller,
• a second valve means actuated by said second timer to permit a flow of liquid sealant to said spray nozzle,
• said first timer being controllable with respect to said second timer to permit continued flow of high pressure air to said nozzle and adapted to be impinged on the sealant deposit in said holes after said second timer has deactivated said second valve means to cease flow of liquid sealant to said spray nozzle.