摘要 |
<p>A polygonal frame self-locking bicycle includes a head tube mounting a wheel-containing front fork, a down tube rigidly connected between the head tube and a pedal crank housing, a seat tube mounting a rear fork and wheel and rigidly connected to the crank housing and a top tube locking with and demountable from at least one of the head and seat tubes. Preferably, a top tube end is key-locked to the seat tube and the other end affixed to a clamping cylinder around the head tube. Loosening of the clamping cylinder permits pivoting an unlocked top tube to open a space between the seat and head tubes. The demounted top tube forms a frame opening that can be leaned past a vertical pole and the top tube remounted and relocked locking the frame about the pole.</p> |