Sliding variable resistor

A sliding variable resistor, comprising:

• a sliding base, including a manipulating handle, at least one first through hole, and at least one variable resistor sheet, wherein the manipulating handle is provided with a fastening hole;
• a first supporting pole, inserted into the at least one first through hole;
• two buffering members, each including a first buffering seat and at least one first protrusion, wherein the first supporting pole has its two ends abut against the first buffering seats, respectively;
• a substrate, including at least two holes, wherein the at least one first protrusion is engaged with the at least two holes, respectively;
• a casing assembly, wherein the two buffering members are arranged in the casing assembly;
• an anchoring plate, fixedly arranged on the casing assembly, and including a long window and an axle hole;
• a driving member, fixedly arranged at an end of the anchoring plate, and including a motor and a driving wheel, wherein the motor includes a rotating shaft passing through the axle hole, and the driving wheel is fixed to the rotating shaft and rotates together therewith;
• a driven member, fixedly arranged at another other end of the anchoring plate, and including a threaded pillar and a driven wheel, wherein the driven wheel is pivotally arranged on the threaded pillar;
• a belt, engaged with the driving wheel and the driven wheel, respectively;
• and
• a belt guard, including at least one fastening portion and an engaging portion such that the at least one fastening portion is fastened to the fastening hole, wherein the engaging portion is engaged with the belt.