Patent ID: 7499256

Claim:
An improvement on an electricity-conducting roller structure, comprising a hub joined to a lower end of a frame of a vehicle; and an electricity-conducting roller module fitted to a bottom of the hub; the electricity-conducting roller module including: (a) a fixed supporting member, the fixed supporting member including a connecting portion securely joined to the bottom of the hub; the fixed supporting member including a pivotal portion adjoining the connecting portion; the pivotal portion having a fastening protrusion on an inner side thereof; the pivotal portion having a pivotal hole thereon; (b) a swinging support member pivoting on the fixed support member; the swinging support member having a pivotal hole thereon; the swinging support member being pivoted to the pivotal portion of the fixed supporting member by means of a pivotal shaft passed through both the pivotal holes; the swinging support member having a through hole on a lower end thereof; (c) an elastic element positioned around the pivotal shaft to bias the swinging support member downwards; the elastic element having first and second terminal portions at two ends thereof; the first terminal portion being fastened to the fastening protrusion of the fixed supporting member; the second terminal portion of the elastic element being pressed against the swinging support member; and (d) an electricity-conducting roller, the electricity-conducting roller having a through hole; the electricity-conducting roller being joined to the swinging support member by means of an axle rod passed through the through hole thereof as well as the through hole of the swinging support member.