Mouse roller module

A mouse roller module, comprising:

• a roller comprising a recess, wherein the recess has a toothed surface;
• a swinging arm comprising a contacting part, a linking part and an adjusting part, wherein the contacting part is connected with a first elastic element, and the first elastic element provides an elastic force to the contacting part, so that the contacting part provides a pressing force to the toothed surface;
• a movable block, wherein when the adjusting part is pushed by the movable block, the swinging arm performs a swinging motion by using the linking part as a fulcrum;
• and
• an adjusting device for adjusting a position of a piston, wherein the movable block is pushed by the piston,
• wherein while the position of the piston is adjusted by the adjusting device, the movable block is moved and the swinging arm performs the swinging motion, wherein the pressing force of the contacting part provided to the toothed surface is adjusted in response to the swinging motion.