Floor polisher

A floor polisher having a pad and means for causing, while the floor polisher is travelling, said pad to rotate at a high speed to polish a floor, said floor polisher comprising:

• a vertically moving mechanism adapted to move said pad in the vertical direction with respect to the floor;
• a ground pressure adjusting mechanism connected to said vertically moving mechanism for maintaining a ground pressure of the pad at a set pressure by controlling said vertically moving mechanism;
• and
• a floor protecting mechanism connected to said vertically moving mechanism for controlling said vertically moving mechanism to lift the pad immediately when the travel of the floor polisher is stopped.