Grinder with easily installable/detachable grinding disc

A grinder with easily installable/detachable grinding disc, comprising:

• a main body, a driving unit being disposed in a main body, a rotary shaft being pivotally connected with a bottom end of the driving unit and drivable by the driving unit, an annular toothed section being formed on a circumference of the rotary shaft;
• a bracket having a circular body section formed with a central circular hole, the bracket being disposed at bottom end of the main body and rotatable to change angular position;
• a support tray formed with a central circular hole, at least two rail channels being radially formed on the support tray, the support tray being disposed at the bottom end of the main body and concentric with the bracket;
• and
• detent members the number of which is equal to the number of the rail channels, the detent members being respectively disposed in the rail channels and slidable along the rail channels, the detent members being connected with the bracket, at least one arched toothed section being formed at inner end of at least one detent member, whereby when turning the bracket, the detent members are synchronously driven to displace along the rail channels between an opened position and a closed position;
• the rotary shaft extending through the bracket and the support tray, the toothed section of the rotary shaft and the arched toothed section of the detent member being positioned at the same height;
• whereby when the detent members are positioned in the closed position, the arched toothed section is engaged with the annular toothed section, while when the detent members are positioned in the opened position, the arched toothed section releases the annular toothed section.