United States Patent: 5544382, Giuliani, et al.

Pacing toothbrush
Issued: August 13, 1996
A vibrating toothbrush, which includes a handle member, an elongated arm which has a brush head at the distal end thereof, and a drive assembly for moving the brush head at a selected velocity. Responsive to an on/off switch on the toothbrush is an on/off variable, which enables a master clock to produce a drive signal, the on/off variable being reset by a 120-second timer. A quadtimer variable, when in the enabled state, is responsive to the on/off switch to produce an audible signal and a difference in brush velocity at 30-second intervals within the 120-second period.

Inventors: Giuliani; David (Mercer Island, WA), McMahon; Ryan W. (Seattle, WA), Engel; David (Seattle, WA)
Assignee: Optiva Corporation (Bellevue, WA)
Appl. No.: 08/306,132
Filed: September 14, 1994
View full patent here.


One of my most innovative accomplishments is creating the timer in the Sonicare electric toothbrush which improved peoples’ dental health. This timer provided feedback in 30-second increments for two minutes encouraging users to brush longer and evenly throughout the mouth.

It is widely understood that people don’t brush for long enough. Dental professionals also know that people brush teeth unevenly with right-handers brushing more on the left side of their mouth and left-handers on the right. Helping people brush an equal amount on the left and right helps reduce gingivitis and periodontal pockets, improving overall dental health.

It sounds obvious now, but adding a timer to an electric toothbrush had never been done. Existing competitive products used rotational electrical motors and had no need for circuitry that could be used as a timer. Sonicare’s use of a microcontroller to control the toothbrush was novel and presented opportunities to add new functionality.  Adding a two-minute timer that beeped every 30 seconds to the code running on the microcontroller was simple. The timer represented a novel and innovative capability, improving peoples’ dental health, creating a differentiated product and improving company profitability.