It is said that the automatic case sealer was invented in 1940 by the ABC Company of Quincy, IL. ABC has been a leading producer of these machines ever since. For years, most case sealers used hotmelt glue to seal the cases because hot melt seals quickly. Nordson Corporation of Ohio has been one of the main producers of hot melt glue and glue heating and dispensing equipment.
In an automatic case sealer, the cartons come to the plant folded flat and stacked. A vacuum mechanism pulls a carton off the stack and opens it. The bottom flaps get hotmelt glue applied to them and then they are pressed shut by plow-shaped arms as they pass through the machine on a chain conveyor. That is the case erection part of the operation. Sometime the case is filled in the section of the same machine or sometimes it is removed and sent a separate case packing machine. When the case is filled, the top flaps are closed by essentially the same method as the bottom flaps.
In recent years, these has been increasing use of adhesive tape rather than hot melt to seal the case. This allows the use of a simpler, less expensive machine, as well as less mess and less clean up. The 3M company has been a leader in this technology. Loveshaw is another firm that is active in this area. Case tapers are more easily adjustable than hotmelt sealers and they can be built to accept random cases. One case can be a different size and shape from the one that preceded it.
A standard cardboard box is known in the industry as an RSC case. Most cases are of this type. Some packaging operations, however, use special die cut cases. These are more espensive but they allow the use of more efficient closing equipment. Some cases have an extended to flap. These are called wraparound cases and they are used in a machine called a wraparound case sealer which opens, packs and seals the case in easy operation.