IMPROVED MECHANICAL TOOTHBRUSH HAVING OPPOSED DUAL HEADS ANDHAVING OSCILLATORY MOVEMENT

摘要

An electric toothbrush is provided with an electric motor and a driving mechanism. The driving mechanism includes a motion translation means to convert rotary motion to oscillatory movement of a drive shaft adapted to be received on the brush head portion of the electric toothbrush, so as to impart an oscillatory movement of the head portion about its longitudinal axis. A particular driving mechanism includes a flywheel having a drive pin which is received in a cam block secured to the drive shaft. The brush head portion comprises a pair of opposed bristle head portions arranged so as to present two groups of opposed bundles of bristles disposed substantially perpendicularly each to the other. Each of the groups of bundles of bristles comprises a plurality of rows and a plurality of columns of bristle bundles, where the rows aligned parallel to the longitudinal axis of the brush head portion, and the columns are aligned perpendicular to the longitudinal axis of the brush head portion. The bristles in each bundle in each row of bristle bundles are substantially equal in length, and the lengths of the bristles in each row of bristle bundles on each bristle head portion are progressively longer in each successive row of bristle bundles which is further away from the longitudinal axis of the brush head portion than an adjacent row of bristle bundles which is closer to the longitudinal axis of the brush head portion. The outer ends of the respective row of bristle bundles on each bristle head portion which is closest to the longitudinal axis of the brush head portion are spaced less than 0.100 inch from the outer ends of the respective opposed row of bristle bundles on the other bristle head portion.