MECHANICAL KINEMATIC CIRCUIT WITH ECCENTRIC MOTOR FOR RESONANCE ELECTRIC TOOTHBRUSH Russian patent published in 2015 - IPC A61C17/32 

FIELD: personal use articles.

SUBSTANCE: invention relates to the field of medical equipment, in particular, hygiene, is intended for tooth cleaning and characterises a toothbrush. The electric toothbrush comprises a drive unit, an eccentric element, a spring unit, a toothbrush head with bristles and a toothbrush head shaft. The drive unit contains a battery and a DC electric motor having a motor housing with the motor rotary output shaft branching off its rear butt end surface. The eccentric element is mounted on the motor output shaft or connected to the latter with the help of another element and rotates together with it. The spring unit contains a spring element characterised by torsional rigidity which results in occurrence of a rotary system resonance frequency lower than the rotary system resonance frequency determining the torsional rigidity. The front butt end surface of the motor housing is attached to the proximal end of the spring unit designed with the possibility of free movement while the other end of the spring unit is in a fixed position so that the motor oscillates together with the spring element. The toothbrush head shaft is attached the spring unit, branching off distally from it. The toothbrush head is attached to the toothbrush head shaft; in the process of the eccentric rotation at the selected frequency an oscillatory movement of the spring element is created which results in the toothbrush head shaft and the toothbrush head oscillating together with it.

EFFECT: invention enables extension of the available range of technical means ensuring usage of a DC electric motor for mechanical excitation of the spring unit in its resonance mode and having no problems related to application of an electromagnetic clutch such as insufficient starting torque and re-adjustment.

10 cl, 4 dwg