Patent attributes
A power tool has a driving shaft driving a working element, a fastening piece fastening the working element to the driving shaft having a projecting shaft insertable into the driving shaft, a locking assembly locking the projecting shaft in the driving shaft having a locking member wherein the locking member has a locking position for locking the projecting shaft with the driving shaft and a loosening position for loosening the projecting shaft with the driving shaft. At the locking position, the fastening piece is pressed towards an end portion of the driving shaft by an elastic component. The locking assembly further includes a movable member arranged outside of the driving shaft, the movable member having a first portion and a second portion which can be directly or indirectly mated with the locking member wherein a radial distance of the first portion relative to a shaft center of the driving shaft is unequal to that of the second portion relative to the shaft center of the driving shaft.
