Lightweight pressing rivet nut for automobile

The invention discloses a lightweight pressing rivet nut for an automobile, relates to the technical field of pressing rivet nuts, and aims to solve the problems that after an existing pressing rivet nut and a thin plate are laminated, the limiting effect is poor, and the overall compactness is high. A nut rod is arranged at one end of a supporting disc; a plurality of supporting face convex straight teeth which are annularly distributed at equal intervals are arranged on the face, close to the nut rod, of the supporting disc; semi-elliptic cylinder grooves are formed in the supporting face convex straight teeth; semi-elliptic cylinder inlets are formed in the ends, close to an outer ring of the supporting disc, of the semi-elliptic cylinder grooves; a limiting groove is formed in the upper end of each semi-elliptic cylinder groove; a plurality of nut rod concave straight teeth are arranged at the end, close to the supporting disc, of the nut rod; a bolt inner blind hole is formed in the nut rod; the opening