Mechanical switch structure

A mechanical switch structure, comprising:

• a keycap;
• a base plate, disposed under the keycap, having a guiding opening;
• a scissor unit, arranged between the keycap and the base plate, to guide the keycap upward or downward along a pressing direction;
• a receiving housing, connected to a bottom of the base plate, the receiving housing having a first accommodation corresponding to the guiding opening, and a second accommodation formed at one side of the first accommodation;
• a guiding unit, movably received in the first accommodation along a pressing direction of the keycap, and disposed in the guiding opening;
• wherein the guiding unit is formed with a hillside portion on a periphery thereof;
• a first elastic element, having two ends respectively attached to the guiding unit and the first accommodation, to provide the guiding unit an elastic force parallel to the pressing direction;
• and
• a resistance module, having an abutting unit and a second elastic unit, the abutting unit being abutted against the hillside portion of the guiding unit, and in which the hillside portion has an undulation surface facing the abutting unit;
• wherein the second elastic unit is received in the second accommodation and provides the abutting unit with an elastic force toward the guiding unit;
• wherein the abutting unit is abutted against the undulation surface of the hillside portion to provide different resistive forces during a pressing stroke of the keycap.