Patent ID: 7960877

Claim:
An electric vertical-type reciprocating motion toothbrush, comprising: at least a brush head; a handle casing; a power source received in said casing; and a spring motor supported in said casing and powered by said power source, wherein said spring motor comprises: a motor unit; a motor housing receiving said motor unit therein; a rotary shaft coaxially extended from said motor unit to a front end of said motor housing to locate at an exterior side of said motor unit and said motor housing to connect with said brush head outside said handle casing; and a torsion spring which is a spiral spring being disposed around said rotary shaft and having an inner end and an outer end, wherein said inner end of said spiral spring is affixed with said rotary shaft and said outer end of said spiral spring is affixed to said motor housing, wherein a DC pulse power source, having constant voltage, frequency and duty cycle, is constantly inputted to said spring motor, said motor unit generating a pulse output to drive said rotary shaft to rotate to one rotational direction, wherein at a high pulse period, said rotary shaft starts moving from a static state to rotate a predetermined rotational angle and said rotary shaft outputs a mechanical torque at said rotational direction of said rotary shaft and said spiral spring also obtains a torque force at the same time, and at a low pulse period, said rotary shaft stops rotating and said spiral spring applies a spring force against said rotary shaft to drive said rotary shaft to rotate backward in a direction opposite to said rotational direction and be forced to rotate back to said static state by said spring force, and thus said rotary shaft of said spring motor completes a full cycle of reciprocating rotational output, wherein when said pulse power source is continually inputting to said spring motor, said rotary shaft continually keeps completing each reciprocating outputting of mechanical torsion movement and said brush head connected with said rotary shaft is driven to provide a vertically reciprocating motion for brushing teeth up and down within a predetermined swing angle range while said pulse power source is inputted to said spring motor.