Progressive rear suspension for bicycles with a deformable double loop quadrilateral configuration

摘要

The invention relates to a rear wheel suspension for a bicycle, which is based on a four pivot system. The compression-extension of the suspension element shock-absorber spring is caused by deformation of a hinged double loop quadrilateral formed by the frame, a fork that pivots relative to the frame above the axis of the bottom bracket, and an upper arm and an articulated rod on each side of the bicycle. The articulated rods pivot on the frame behind the tube of the saddle. The top arms form two triangles having pivots at their back vertex where they are attached to the fork and at the front-upper vertex where they are attached to the articulated rods. The suspension element connects the front-lower vertex of said arms to the frame in front of the tube of the saddle. Said configuration provides great rigidity and high progressiveness in hardening.