TANDEM BICYCLE Russian patent published in 2004 - IPC

FIELD: transport engineering.

SUBSTANCE: invention relates to frame of tandem bicycle. Each wheel of bicycle is provided with pedal drive built into hub 4,5. Frame consists of front part and rear part 2 hinge-coupled by axle 3. Front part is made in form of seat for first rider being provided with U-shaped backrest 15 and two L-shaped arm-rests. It has also two pairs of posts 9, 10 orientated radially relative to axle of wheel and rigidly coupled with brackets connecting hub 4 and front part. Second rider can use as handlebar said L-shaped armrests and/or U-shaped backrest 15. rear part 2 consists of five rigidly connected tubes in form of tetrahedron flattened along line of sixth absent rib, geometric axis of rear wheel being said sixth rib. Two vertices of tetrahedron from both sides of wheel are rigidly secured on brackets of hub 5, and handlebar axle 3 is located in third vertex of tetrahedron. Post of saddle 16 is located in fourth vertex of tetrahedron.

EFFECT: provision of compact design of tandem bicycle.

2 cl, 3 dwg