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In a transmission for a steerable drive wheel (4) of a forklift, which transmission is pivotable around a vertical axle (8) and contains a spur gear stage (24, 26) and a second reduction stage formed by a pinion shaft (28, 30) and a bevel wheel (36), the second reduction stage is designed as hypoid

In a transmission for a steerable drive wheel (4) of a forklift, which transmission is pivotable around a vertical axle (8) and contains a spur gear stage (24, 26) and a second reduction stage formed by a pinion shaft (28, 30) and a bevel wheel (36), the second reduction stage is designed as hypoid wheel set (30, 36) with positive axle offset. Unlike the designs known already, it is hereby possible, by adhering to preset limits of the outer dimensions and a preset reduction ratio, to obtain a toothing of more supporting capacity and a thicker pinion shaft (28) so that the loads of the tooth flanks are canceled and it is possible to use a design of a high loaded pinion bearing (34) having more supporting capacity.

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1. A transmission for a steerable drive wheel of a forklift comprising:a vehicle chassis supporting a transmission housing (12, 14), and the transmission housing (12, 14) being rotatable relative to a vertical drive axle (8); an electric motor (2) connected to a first end of the vertical drive axle

1. A transmission for a steerable drive wheel of a forklift comprising:a vehicle chassis supporting a transmission housing (12, 14), and the transmission housing (12, 14) being rotatable relative to a vertical drive axle (8); an electric motor (2) connected to a first end of the vertical drive axle (8) to supply driving power to the vertical drive axle (8), and a second end of the vertical drive axle (8) supporting a pinion (24); a vertical pinion shaft (28) having a rotational pinion axis (PA), the pinion shaft (28) also having a first end and a second end, the first end of the pinion shaft (28) supporting a spur gear (26), and the spur gear (26) matingly engaging with the pinion (24) of the vertical drive axle (8) to transmit driving power from the electric motor (2) to the pinion shaft (28); the second end of the pinion shaft (28) supporting a bevel hypoid pinion (30); a horizontal output shaft (40) having a rotational output shaft axis (SA) and the horizontal output shaft (40) having a first end and a second end; the first end of the output shaft (40) being coaxially connected to a bevel wheel (36), and the bevel wheel (36) having a bevel wheel surface (35); the second end of the output shaft (40) supporting the steerable drive wheel (4), and the bevel wheel (36) is located between the rotational pinion axis (PA) of the vertical pinion shaft (28) and the steerable drive wheel (4); wherein during operation of the transmission, the electric motor (2) drives the vertical drive axle (8), the pinion (24), the spur gear (26), the vertical pinion shaft (28), the bevel pinion (30), the bevel wheel (36) and the horizontal output shaft (40) to supply driving power to the steerable drive wheel (4); and wherein the bevel wheel (36) matingly engages the bevel-pinion (30) at an engagement point on the bevel wheel surface (35) wherein the engagement point is offset horizontally to and vertically above the output shaft axis (SA) such that the rotational pinion axis (PA) of the vertical pinion shaft (28) is oriented parallel to and spaced apart horizontally from a plane passing through the output shaft axis (SA) of the horizontal output shaft (40) and vertically bisecting the bevel wheel (36) into two quadrants and does not intersect with the output shaft axis (SA) of the horizontal output shaft; wherein a set of teeth of the hypoid pinion gear (30) and a mating set of teeth of the bevel wheel (36) are a hypoid wheel set in which both sets of teeth are helically cut teeth; and the horizontal offset of the rotational pinion axis (PA) of the vertical pinion shaft (28) relative to the output shaft axis (SA) of the horizontal output shaft (40) result in a contact angle between the teeth of the hypoid pinion gear (30) and the mating teeth of the bevel wheel (36) wherein the helically cut teeth of the hypoid pinion gear (30) have a first helix angle which is larger than a second helix angle of the mating helically cut teeth of the bevel wheel (36); whereby the larger first helix angle of the hypoid pinion gear (30) with respect to the second helix angle of the bevel wheel (36) allows a larger diameter of the hypoid pinion gear (30) for a given number of hypoid pinion gear (30) teeth, thereby providing an increased flank length and overlap per tooth of the hypoid pinion gear (30) and the bevel wheel (36) and an increased diameter of the pinion shaft (28), thereby providing increased load bearing capacity of the transmission.