SMALL-SIZED ELECTRICAL APPLIANCE INDICATING BATTERY CHARGE STATUS Russian patent published in 2012 - IPC B26B19/12 

FIELD: personal use articles.

SUBSTANCE: small-sized electrical appliance, battery powered, driven by an oscillating or linear electric motor controlled by an electronic circuit which is connected with a scheme to identify and indicate the status of the battery charge. When a certain state of charge reached or in case of low charge, the control circuit adjusts the oscillating electric motor or linear electric motor so that the noise of the electric motor changes.

EFFECT: user is provided an opportunity to determine by the noise of electric motor when it can stop because of low battery charge.

6 cl, 1 dwg