Leak detection apparatus for aerosol containers

Claim 1

An apparatus by which leaks in filled pressurized containers may be detected at production line speeds using an ultrasonic leak detection method, said apparatus comprising: a base; a table rotatably connected to said base, said table being peripherally adjacent to a conveyor line for filled pressurized containers and having a peripheral portion adapted to carry containers; shield means connected to said base and defining a tunnel above and along a portion of said peripheral portion, said shield means including extension portions extending from the base of either wall of said tunnel and closely adjacent to surfaces of said table, said shield means comprising an acoustic barrier material, said extension portions and the adjacent table surfaces having at least one facing surface of an acousticabsorbing material affixed therebetween; blocks peripherally spaced on said peripheral portion of said table defining spaces therebetween for containers, said blocks having peripherally spaced end walls comprising acoustic barrier material, and having adjacent side walls spaced radially with respect to the axis of rotation of said table, said side walls and the inner surfaces of said tunnel having at least one facing surface of an acoustic-absorbing material; at least one detection chamber defined by said shield means and adjacent end walls of adjacent blocks; an ultrasonic noise detector located in said at least one detection chamber; means to feed cans seriatim from said conveyor line onto said spaces of said table at a first location off an end of said tunnel; means to rotate said table to locate said successive containers seriatim in said at least one detection chamber; means downstream of said tunnel to reject defective containers; means to activate said reject means in response to a signal from said ultrasonic noise detector; and means to remove containers from said table.

Claim 2

An apparatus by which leaks in filled pressurized containers may be detected at production line speeds using an ultrasonic leak detection method, said apparatus comprising: a base; a table rotatably connected to said base, said table being peripherally adjacent to a conveyor line for filled pressurized containers and having a peripheral portion adapted to carry containers; shield means connected to said base and defining a tunnel above and along a portion of said peripheral portion, said shield means including extension portions extending from the base of either wall of said tunnel and closely adjacent to surfaces of said table, said shield means comprising an acoustic barrier material, said extension portions and the adjacent table surfaces having at least one facing surface of an acousticabsorbing material affixed therebetween; blocks peripherally spaced on said peripheral portion of said table defining spaces therebetween for containers, said blocks having peripherally spaced end walls comprising acoustic barrier material, and having adjacent side walls spaced radially with respect to the axis of rotation of said table, said side walls and the inner surfaces of said tunnel having at least one facing surface of an acoustic-absorbing material; at least one detection chamber defined by said shield means and adjacent end walls of adjacent blocks; an ultrasonic noise detector located in said at least one detection chamber; means to feed cans seriatim from said conveyor line onto said spaces of said table at a first location off an end of said tunnel; means to rotate said table to locate said successive containers seriatim in said at least one detection chamber; means downstream of said tunnel to reject defective containers; means to activate said reject means in response to a signal from said ultrasonic noise detector; and means to remove containers from said table.