US Patent 8074321 Dual-tank vacuum cleaner

The disclosed vacuum cleaner has a smaller, separable vacuum unit that is releasably attached to a larger, base unit tank assembly. It provides a combination vacuum cleaner that has small- and large-capacity configurations suited for vacuum applications having different volumes, locations, or other features. The vacuum cleaner includes a single vacuum source sized for use with the larger tank structure, yet coupled to and removable integrally with the smaller vacuum unit. The smaller vacuum unit can be quickly and easily attached to and removed from the larger tank assembly to facilitate use of the vacuum cleaner in the desired configuration.