BICYCLE Russian patent published in 1996 - IPC

FIELD: mechanical engineering; tandem bicycles with front-upper drive and reciprocating angular movement cranks. SUBSTANCE: tandem bicycle has frame with lower tube, rear wheel, front driving wheel, drive on forked bracket of upper tube, handlebars and saddles. Saddle is installed on rear bushing. Hinge-connected with bushing is rear end of upper tube; front part is hinge connected with front bushing on fork which is also hinge-connected with end pieces of tube. Parts of upper tube are connected by telescopic members with clamp-shaped bracket for sheaves of drive cable whose ends are secured on sliders of drive cranks. Handlebars are connected by control cable with fork or with post of wheel. Drive has two semi-shafts with pin-and-slot joint or one shaft with driving sprocket with conditional number of teeth on shaft or on supports of semi-shafts and rigidly connected with semi-shafts of cranks. Conditional number of teeth of driving sprocket is 70 or more, and than of driven sprocket, 13 or less. EFFECT: enlarged operating capabilities. 3 cl, 10 dwg