Transmission device between an input drive shaft and an output shaft, such as the shaft for driving the wheels of a travelling machine

Transmission device between an input drive shaft (1) and an output shaft (2), such as the shaft for driving the wheels of a travelling machine, the said device comprising a housing (3) inside which are placed at least partially a reduction gear mechanism and a progressive cone clutch mechanism (6), the said reduction gear mechanism comprising a driving member (4) engaged with a driven member (5), the driven member (5) of the reduction gear mechanism being formed by a gearwheel (5) mounted so as to rotate freely on the output shaft (2) and able to be coupled to/uncoupled from the said output shaft (2) by means of the two friction cones (6) of the clutch mechanism, the said cones being placed coaxial to the axial bore (7) of the gearwheel (5) and capable of coming, under the action of a control device (17), into bearing contact with a conical bearing surface (8) of the gearwheel (5), characterized in that the conical bearing surfaces (8) of the gearwheel (5) are, relative to the axis of rotation of the gearwheel (5), offset axially from the gear teeth (9) of the gearwheel (5) and are placed on the same side of the said gear teeth (9).