US Patent 7213289 Battery powered grout brush

A manually operated, handled grout brush has an outer housing which encloses upper and lower contiguous spaces. Electric batteries in the upper space run an electrical motor, which powers gearing to rotate two sets of brushes, a grout brush head with rigid bristles for hard scrubbing and scouring dirty, mildewed, and stained rough grout surfaces, and a tile scrubbing brush head which may include one or two common scrub brushes for cleaning glossy, smooth tile surfaces.