Bicycle, in particular an all-terrain bicycle

#The invention relates to a bicycle, in particular an all-terrain bicycle, comprising frame, a front wheel, a rear wheel, a handle bar for steering the front wheel, a pedal unit, the front wheel, the rear wheel, the handle bar and the pedal unit being rotatably mounted on the frame, a transmission connecting the pedal unit to the rear wheel for transmitting a drive thereto, transmission means connecting the rear wheel to the front wheel for transmitting the drive to the front wheel.

#Various bicycles are already known, in which in addition to the drive assembly for the rear wheel, a drive assembly is provided for the front wheel. A known all-wheel drive for the two wheels of a bicycle according to DE-OS 33 19 105 is provided with a multiple stage variable gear for the conversion of a driving Force, applied via a pedal lever or a motor with a reciprocating or revolving movement onto the wheel hub shafts of the wheels.

#Furthermore, a force transmission--according to the DE-OS 38 31 890--is known, in which the rear wheel and if necessary the front wheel can be driven via a continuously adjustable force transmission through utilization of an oscillating swivel movement of a pedal lever.

#For a better understanding of the invention, the latter is explained in further detail with the aid of the embodiments illustrated in the drawings, in which:

#FIG. 1 shows a bicycle according to the invention, with an additional drive arrangement for the front wheel, in side view;

#FIG. 2 shows a transmission device, according to the invention, of the drive device according to FIG. 1, in schematic, diagrammatic representation;

#FIGS. 1 to 4 show bicycle 1 comprising frame 2, in particular of tubular frame parts 3,4, which are welded or soldered to each other at intersections. In mountings of the fork-shaped frame part 4, a rear wheel 5 is rotatably mounted about an axis 8 running horizontally to a standing surface 6 and perpendicularly in relation to a direction of travel--arrow 7.

#In a mounting 9 of a fork-shaped frame part 10 a front wheel 11 is rotatably mounted about an axis 12 arranged parallel to the axis 8. The fork-shaped frame part 10 has in the direction opposed to the standing surface 6 a cylindrical extension 13, which is rotatably mounted in a tubular frame part 14, arranged approximately vertically, for rotating about a swivel axis 15. To carry out a swivel movement about the swivel axis 15, the extension 13 has a handlebar 16, which is fastened on the extension 13 approximately parallel to the standing surface 6.

#The bicycle 1 has a known drive arrangement 17 for the rear wheel 5, which is formed by a pedal unit 18, Transmission 19 and drive elements 20. The Transmission 19 is formed in a preferred manner by a roller chain 21. The pedal unit 18 and the drive element 20 have sprockets engaging the roller chain. In addition, the drive arrangement 17 comprises a switch device to alter the ratio between the pedal unit 18 and the rear wheel 5. Such a switch arrangement, in which a translation-speed change is brought about by placing the roller chain 21 between different pairs of toothed wheels between the pedal unit 18 and the drive elements 20 of the rear wheel 5, is known for example as Shimao-switching type NEW, as used in bicycles, in particular mountain bikes of the firm KTM. A drive arrangement 22 is arranged between the rear wheel 5 and the front wheel 11, for the transmission of a rotational moment component of the rotational moment imparted to the rear wheel 5 via the drive arrangement 17. This comprises a drive element 23, which is affixed to the drive element 20 so as to rotate therewith, a transmission 24, e.g. a roller chain 21 and a transmission device 25, in particular in the region of the handlebar 16, which further transmits the rotational moment to the front wheel 11 via an--in particular endless--transmission 26, e.g. a roller chain 21 engaging a drive element 27 of the front wheel 11.