Variable sweep helical infeed element

A variable sweep infeed element for a rotary combine is bolted to the infeed section of the rotor drum and extends radially outward therefrom. The element is provided with a forward portion and a rearward portion. The forward portion is the location where the infeed element first contacts the crop mat. The forward portion has a radial section that extending radially outward from the rotor drum and an outermost section is forward swept in the direction of rotor rotation. This forward sweep is most aggressive at the initial feeding point and becomes less aggressive as the forward portion extends longitudinally downstream towards the transition point between the forward portion and the rearward portion. The rearward portion is provided with a radial section extending radially outward from the rotor drum and an outermost.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention is directed to a variable sweep infeed element for a rotary 
combine having a forward portion that is provided with a forward swept 
section and a rearward portion that is provided with a rearward swept 
section. 
2. Description of the Prior Art 
Agricultural combines are large machines that harvest, thresh, separate and 
clean an agricultural crop. The resulting clean grain is stored in a grain 
tank located on the combine. The clean grain can then be transported from 
the grain tank to a truck, grain cart or other receiving bin by an 
unloading auger. 
Rotary combines have one or two large rotors arranged along the 
longitudinal axis of the machine for threshing and separating the 
harvested crop material. These rotors are provided with an infeed section 
for receiving harvested crop material, a threshing section for threshing 
the harvested crop material received from the infeed section and a 
separating section for freeing grain trapped in the threshed crop material 
received from the threshing section. 
The harvested crop is delivered to the infeed section by the feederhouse. 
The crop is arranged in a crop mat which the infeed elements of the rotor 
need to take up and rotate into a helical flow. Previously, feeding 
elements have been arranged with a continuous sweep angle along the length 
of the element, or these infeed elements are rearward swept at the initial 
point of contact with the crop mat and proceed to forward swept as the 
element extends downstream in the longitudinal direction. 
These basic designs are used on all axially arranged rotary combines 
currently being marketed. A common problem for these machines is their 
difficulty in feeding tough, damp or green crop material as well as short, 
dry or slick crop material with the same infeed element geometry. This 
difficulty limits machine throughput and causes the operator to 
significantly reduce the amount of material that is fed to the rotary crop 
processing assemblies. 
SUMMARY 
It is an object of the present invention to provide a variable sweep infeed 
element for a rotary combine which improves material feeding and flow into 
the rotary crop processing assemblies. 
The helical infeed element of the present invention is a helical element 
bolted to the infeed section of the rotor drum and extends radially 
outward therefrom. The element is provided with a forward portion and a 
rearward portion. The forward portion is the location where the infeed 
element first contacts the crop mat. The forward portion has a radial 
section that extending radially outward from the rotor drum and an 
outermost section is forward swept in the direction of rotor rotation. 
This forward sweep is most aggressive at the initial feeding point and 
becomes less aggressive as the forward portion extends longitudinally 
downstream towards the transition point between the forward portion and 
the rearward portion. The rearward portion is provided with a radial 
section extending radially outward from the rotor drum and an outermost 
section which is backswept away from the direction of rotor rotation.

DETAILED DESCRIPTION 
FIG. 1 shows an agricultural combine 10 comprising a supporting structure 
12 having ground engaging wheels 14 extending from the supporting 
structure. A harvesting platform 16 is used for harvesting a crop and 
directing it to a feederhouse 18. The harvested crop is directed by the 
feederhouse 18 to a beater 20. The beater directs the crop upwardly 
through an inlet transition section 22 to the axial crop processing unit 
24. 
The crop processing unit threshes and separates the harvested crop 
material. Grain and chaff fall through grates on the bottom of the unit 24 
to cleaning system 26. The cleaning system 26 removes the chaff and 
directs the clean grain to a clean grain elevator (not shown). The clean 
grain elevator deposits the clean grain in grain tank 28. The clean grain 
in the tank can be unloaded into a grain cart or truck by unloading auger 
30. 
Threshed and separated straw is discharged from the axial crop processing 
unit through outlet 32 to discharge beater 34. The discharge beater in 
turn propels the straw out the rear of the combine. The operation of the 
combine is controlled from operator's cab 35. 
The axial crop processing unit comprises a cylindrical rotor housing 36 and 
a rotor 37 located inside the housing 36. The front part of the rotor and 
the rotor housing define the infeed section 38 of the crop processing 
unit. Longitudinally downstream from the infeed section 38 are threshing 
section 39 and separating section 40. The rotor in the infeed section is 
provided with a conical rotor drum 41 having helical infeed elements 42 
for engaging harvested crop material received from the beater 20 and inlet 
transition section 22. Immediately downstream from the infeed section is 
the threshing section 39 of the crop processing unit 24. In the threshing 
section 39 the rotor comprises a cylindrical rotor drum 49 having a number 
of threshing elements 50 for threshing the harvested crop material 
received from the infeed section 38. Downstream from the threshing section 
39 is the separating section 40 wherein the grain trapped in the crop 
material is released and falls through the grate to the cleaning system 
28. 
The infeed elements are best illustrated in FIG. 2. The infeed elements 42 
are bolted to conical rotor drum 41 by mounting assemblies 52. The infeed 
elements 42 are provided with a forward portion 54 and a rearward portion 
58. The forward portion is provided with a radially extending section 60 
and an outermost section 62 that is forwardly swept in the direction of 
rotation. Similarly the rearward section 58 is provided with an outwardly 
extending radial section 66 and an outermost rearward swept section 68. 
The outermost section 62 of the forward portion 54 initially engages the 
crop mat in a very aggressive manner cupping and engaging the crop 
material to quickly transition it into a helical flow. The forward swept 
portion extends longitudinally downstream to a lessening degree until the 
helical flow of the crop material is fully established. As the infeed 
element transitions inwardly in a radial direction the forward portion 54 
transitions into the radially extending section 60. In this way the 
forward portion provides a means of aggressively engaging the crop mat but 
not allowing the crop mat to penetrate to deeply towards the rotating drum 
and accumulating non-uniformly between the infeed elements 42. 
The outermost portion 68 of the rearward portion 58 is back swept away from 
the direction of rotation to release the crop material and smear it 
outward towards the rotor casing thereby evenly distributing the crop 
material between the infeed elements. This provides a means of allowing 
the radial inner crop material to continue flowing in a helical path 
driven by the infeed element 42. The crop material can easily transition 
outward over the back swept outermost portion to provide a uniform helical 
distribution of crop material flow between the infeed element 42 and the 
rotor housing 36. 
The invention should not be limited by the above described embodiments, but 
should be limited solely by the claims that follow: