US 4,138,837 A · Variable speed reversible drive for a harvesting apparatus

Abstract

An agricultural crop harvester's feeding and gathering units are driven by a power source on the harvester through a sheave assembly journaled on a countershaft mounted towards the rear of the feeding unit. Power is then transmitted by a variable ratio V-belt drive to a speed reducing and direction reversing planetary gear unit mounted forwardly on the feeding unit and finally to the gathering and feeding mechanisms by drives of conventional design. In the variable ratio V-belt drive, the effective diameter of a split sheave output portion of the countershaft sheave assembly is selectively adjusted hydraulically while, in inverse response, the effective diameter of a spring loaded variable driven split sheave, integral with the planetary gear unit, adjusts automatically. In addition, the driven sheave is provided with a coaxial cam arrangement responsive to changes in torque transmitted so that its effective diameter also adjusts automatically to provide appropriate belt tension. Interposing a speed reducing planetary gear unit in the drive system following the V-belt drive makes possible the use of comparatively higher belt speeds and smaller sheave diameters and facilitates provision of a selectively reversible drive to the gathering and feeding units. The reversed speed of rotation of the output of the planetary unit is substantially lower than its forward speed.

Claims17

Dependent claims

In a header for a mobile harvesting machine, the header including gathering and feeding units and a power input shaft, the harvesting machine carrying a power source, an improved drive for the header comprising:

a drive sheave connected to and driven by the power source;
a driven sheave, coaxial with and driving the input shaft, including a first sheave half, a second sheave half coaxial with and axially shiftable relative to the first sheave half and cooperating with it so as to define a variable effective diameter V-belt groove, at least one of the sheave halves being rotationally deflectible relative to the input shaft, and automatic means coaxial with the driven sheave for axially biasing the second sheave half towards the first sheave half for adjusting the effective diameter in response to rotational deflection between the driven sheave and the input shaft caused by changes in the torque transmitted through the input shaft to the header;
and
a V-belt trained around the drive and driven sheaves, engaging the driven sheave at its effective diameter, for transmitting power from the drive sheave to the driven sheave, the automatic adjustment of the driven sheave serving to maintain appropriate tension in the V-belt.

1 more element

In a mobile harvesting machine having a crop gathering unit, a crop processing unit, a feeding unit for transferring the gathered crop to the processing unit and a power source, an improved drive system for driving said gathering and feeding units comprising:

a countershaft carried on the machine;
a rotatable input unit journaled on the countershaft, drivingly connected to the power source and including a drive sheave having a V groove;
a transmission unit mounted on the machine including a torque responsive driven sheave having an adjustable V groove and automatic means for adjusting the effective diameter of the groove in response to changes in torque transmitted by the sheave, an output shaft drivingly connected to the gathering and feeding unit, a speed reducing planetary gear set drivingly connected with the driven sheave and means for drivingly connecting the planetary gear set with the output shaft;
and
a V-belt engaging the V grooves of the drive and driven sheaves and drivingly connecting the input unit with the transmission unit.

2 more elements

Dependencies are inferred from the claim text.

Variable speed reversible drive for a harvesting apparatus

Life of this patent

Variable speed reversible drive for a harvesting apparatus

Life of this patent

Abstract

Claims17