Structure of assembling a plastic locking device with a surface material

An assembled structure of a plastic locking device and a surface material, which comprises a plastic locking device, a rivet fastener, and a surface material in the form of a flexible sheet, characterized in that:

• the plastic locking device has a peripheral that forms a through-hole;
• the surface material forms a hole;
• and
• the rivet fastener element comprises a female button and a male button, the male button having a plate body that is provided with a protruded pillar having a smooth cylindrical circumferential surface, the female button comprising a plate body and a hollow tube that has an inner circumferential wall extending in an axial direction from the plate body of the female button toward the protruded pillar of the male button and forming locking blocks projecting toward a center, the hollow tube of the female button having a free end that is distant from the plate body of the female button and forms an opening that receives insertion of the protruded pillar of the male button into the hollow tube, the locking blocks being in the form of ribs that extend axially and are distributed circumferentially on the inner circumferential wall of the hollow tube to establish force interference between the ribs of the hollow tube and the smooth cylindrical circumferential surface of the protruded pillar;
• wherein the plastic locking device is positionable on the surface material with the through-hole of the plastic locking device overlapping the hole of the surface material and the female button is positionable on the surface material to have the hollow tube transfixed into the through-hole of the plastic locking device and the hole of the surface material, the male button being arranged to have the protruded pillar align with the opening of the hollow tube of the female button and adapted to receive a punch pin to apply a force thereto such that the protruded pillar of the male button is forced into the hollow tube of the female button to have the rivet fastener element riveted to connect the plastic locking device with the surface material thereby making the plastic locking device tightly set and coupled to the surface material;
• wherein the rivet fastener element is made of zinc;
• and
• wherein the plastic locking device and the rivet fastener are free of threading so that operation of assembling the plastic locking device with a surface material is done without threading coupling.