| 摘要 |
A dental cleaning appliance such as an electric toothbrush with a nozzle 36 for delivering bursts of working fluid to the teeth of a user includes a fluid delivery system which is moveable relative to a handle as the appliance is moved along the teeth of the user. When movement of the nozzle 36 is sensed entering an interproximal gap, delivery of working fluid is actuated to dislodge matter therein. To prevent undesired ejection of bursts of fluid, a control circuit detects the magnitude of current drawn by a motor which drives a bristle carrier 30, and only permits manual or automatic delivery of spray when the current is above a threshold value, indicating that brush head 29 is being pressed against a users teeth. When current drawn by the motor exceeds a second, higher threshold value an alert may be generated to warn that the brush is being pressed too firmly against the users teeth. |
