Rotor for a combine

A rotor for an axial flow type combine has a generally cylindrical main body portion with a pair of rasp bars mounted longitudinally thereon. The forward portion of each of the rasp bars is inclined outwardly and rearwardly to provide an infeed spacing between the forward portion of the rotor and associated concave which will accommodate abnormal masses of crop material and function to thin out these masses prior to further axial movement of the crop material rearwardly into the threshing and separating region of the rotor.

BACKGROUND OF THE INVENTION 
The present invention relates to axial flow type harvesting machines and, 
more particularly, is directed to the structure of the rasp bars on the 
rotor of the machine. 
In axial flow combines, the threshing and separating mechanism extends 
generally longitudinally (fore-and-aft) to the direction of travel of the 
combine and generally comprises a rotor rotatably mounted in a casing 
having a threshing concave and an separating grate. Crop material is fed 
to the forward or inlet end of the rotor and is then spirally conveyed 
within the casing as it moves axially rearwardly therethrough whereby the 
grain is separated from the crop material. There is a relatively small 
clearance between the rotor and the casing, thus making it difficult to 
introduce material into the casing. To increase the feeding capacity of 
the combine, it has been found to be effective to provide an auger means 
on the forward end of the rotor which aggressively transfers the crop 
material from the crop elevator to the inlet end of the threshing and 
separating mechanism. However, it has been found that in certain crop 
conditions, the auger type infeed tends to bunch or intermittently feed 
dense quantities of the crop material as it is moved from the crop 
elevator axially into the threshing compartment. 
The bunching of the crop material at the inlet end of the threshing and 
separating mechanism may cause a multitude of problems. The bunching 
causes an uneven feeding of crop material to the threshing and separating 
mechanism which results in an inefficient operation, overloading of the 
grain-cleaning mechanism and power peak requirements. Further, this 
bunching of crop material may cause a vibration of the machine structure 
which is intense and objectionable being characterized by a hammering 
inside the machine. Also, in extreme cases this bunching of crop material 
may cause jamming of the rotor and breakdown of the machine which results 
in costly repairs. Still another disadvantage is the problem of grain 
crackage which is critical to the price the farmer obtains for his crop. 
To summarize, the bunching of abnormal masses of crop material at the inlet 
of the threshing and separating mechanism often results in an uneven 
transport of the crop, noisy operation, high peak loads on the drive 
means, high power requirements, low capacities, costly repairs, etc. These 
disadvantages are well known to those skilled in the art of the axial flow 
type harvesting machine. The main object of the present invention is to 
substantially alleviate these problems. 
SUMMARY OF THE INVENTION 
According to the present invention there is provided an axial flow type 
harvesting machine having a generally fore-and-aft extending axial flow 
type threshing and separating mechanism which includes generally at least 
one fore-and-aft extending casing means being of generally cylindrical 
cross section and rotor means within the casing means. The casing means 
includes a front threshing concave and a rear separating grate that 
cooperate with a main body portion of the rotor means rotatably mounted in 
the casing for the threshing and separating the grain from the crop 
material. 
Preferably, the rotor means has a generally cylindrical main body portion 
with at least one threshing element extending radially outwardly 
therefrom. The forward portion of the threshing element is sloped or 
tapers outwardly and rearwardly from the front of the rotor to provide a 
space between the forward portion of the rotor and the concave for 
thinning the mat of crop material prior to further spiral rearward 
movement of the material through the casing. 
The present invention provides a smooth flow of crop material through the 
threshing and separating mechanism whereby the overall power requirement 
of the machine is reduced. Furthermore, the smooth flow of crop material 
through the threshing and separating mechanism reduces the likelihood of 
material jamming and the burden of costly repairs. Still further, with 
this smooth flow of crop material, a relatively thin and even mat thereof 
is operated on by the threshing and separating mechanism whereby the 
effectiveness of the latter is increased with the result that grain loss 
is decreased without any sacrifice in the power requirement. Also with 
this present invention, less grain kernels are cracked whereby the quality 
of the harvested grain is increased considerably.

DETAILED DESCRIPTION OF THE INVENTION 
In the following description, right hand and left hand references are 
determined by standing at the rear of the machine facing in a direction of 
forward travel. Also, in the following description, it is to be understood 
that such terms as "forward," "rearward," "left," "upwardly," etc., are 
words of convenience and are not to be construed as limiting terms. 
IN GENERAL 
Referring now to the drawings, and particularly to FIG. 1, there is shown 
an axial flow type combine, being indicated generally by the numeral 10, 
which incorporates the preferred embodiment of the present invention. 
While the combine is of the self-propelled type, the improved structure 
incorporated therein may just as readily be incorporated into a pull-type 
machine. 
The combine comprises a mobile frame or housing means 12 supported on front 
drive wheels 14 and smaller rear steerable wheels 16 (only the right 
wheels being shown in FIG. 1). Supported on the main frame 12 is a 
threshing and separating mechanism 18 in the form of right and left 
threshing and separating units 20,22 (only the left threshing and 
separating unit 20 being shown in FIGS. 1 and 2), an operator's platform 
24, a grain tank 26, grain handling and cleaning means 28 and a rotary 
discharge means 30. A conventional header 32 and crop elevator 34 extend 
forwardly of the machine and the header 32 and elevator 34 are pivotally 
secured to the frame 12 for general vertical movement which is controlled 
by extensible hydraulic cylinders 36. 
As the combine 10 is propelled forwardly over a field, the crop material 
which is to be harvested is severed from the stubble by a sickle bar 
cutter 38 on the header, consolidated laterally by two opposed augers 40 
(shown fragmentary in FIG. 1) which feed the cut crop material centrally 
to the crop elevator 34 which in turns conveys the crop material upwardly 
and rearwardly to the threshing and separating mechanism 18. The material 
received by the threshing and separating mechanism 18 will be threshed and 
separated, that is to say, the crop material (which may be wheat, corn, 
rice, soybeans, rye, grass seed, barley, oats, corn or other similar crop 
materials) is rubbed and beaten whereby the grain, seed, etc. is loosened 
and separated from the straw, stalks, cobs or other discardable part of 
the crop material. While the term grain and straw are used principally 
through this application for convenience, it should be understood that the 
terms are not intended to be limiting. The term grain as used herein thus 
refers to the part of the crop material that may be threshed and separated 
from the discardable part of the crop material which will be referred to 
as straw. 
The straw is discharged from the rear of the threshing and separating 
mechanism 18 onto a discharge plate 42 of the rotary discharge means 30 
which finally discharges the straw to the ground. The grain and other 
material which has been separated from the straw falls onto the grain 
cleaning and handling means 28 which includes means to separate clean 
grain and means to separate unthreshed material (known in the art as 
tailings) from the remainder of the material received in the cleaning 
means. A rotary fan 44 is provided to blow the chaff out the rear of the 
machine as the grain falls through the sieves of the cleaning means 28. 
The cleaned grain is then elevated into the grain tank 26 by an elevator 
46 and the tailings are raised by an elevator 48 and delivered to the 
inlet end of the threshing and separating mechanism 18 where it joins the 
unthreshed grain being fed into the mechanism from the crop conveyor 34 to 
repeat the threshing and separating cycle. The cleaned grain is then 
discharged from the grain tank by an unloading auger 50 which forces the 
grain through a discharge spout 52. 
In the preferred embodiment, the threshing and separating mechanism 18 
takes the form of two units 20,22 (FIG. 4) in adjacent side-by-side 
relation and extending generally longitudinally of the combine. Although, 
the invention is described and shown in an embodiment having two threshing 
and separating units, the principles of this invention are equally 
applicable to a single threshing and separating unit. 
The two units 20,22 of the threshing and separating mechanism 18 each have 
a threshing and separating casing 54 of a generally cylindrical 
configuration, the units being disposed in a contiguous and parallel 
side-by-side relation with the parallel axes of the casings 54 lying in a 
fore-and-aft plane. The units 20,22 are mounted in the combine 10 in an 
upwardly and rearwardly disposition. The casings 54 are open at their 
forward ends to receive unthreshed crop material and have rear openings 
for straw discharge. Each unit 20,22 includes a front threshing section 56 
and a rear separating section 58. The top wall of each casing 54 extending 
longitudinally the entire length of the unit is curved and is provided 
with conveying means in the form of vanes 60 disposed at an angle to the 
radial plane which assists in guiding the crop material rearwardly in a 
generally helical movement along the casings 54. The lower portion of the 
casings 54 are provided with front threshing concaves 62 and rear 
separating grates 64. Outer concave extensions 66 (FIG. 4) complete the 
generally cylindrical casings 54. The concaves 62 are formed by a number 
of longitudinally-extending bars 68 secured to a number of transverse 
arcuate supporting beams 70. Cylindrically curved wires 71 extend through 
the bars 68 to form openings through which grain passes. The separator 
grates 64 are disposed rearwardly of the concaves 62 and complete the 
generally cylindrical casings at the location of the separator section. 
The separator grates 64 are similar to the concaves 62 but the apertures 
between the bars and wires are considerably larger so as to better suit 
their specific function of separating the threshed grain. 
Housed within the casings 54 are right and left hand longitudinally 
extending threshing and separating rotors 72 having front and rear stub 
shafts 74,76 journalled for rotation within suitable bearings mounted on 
the mobile frame or housing 12. The rotors 72, which will be referred to 
in detail hereafter, are so arranged such that they rotate in opposite 
directions downwardly at their adjacent sides, as illustrated by the 
respective arrows in FIG. 4. Mounted on the forward end of the front stub 
shaft 74 of each rotor 72 is a feed means 78 which will be discussed later 
in connection with the discussion of the rotor. 
The crop elevator 34, which is attached to the combine frame 12 forwardly 
of the threshing and separating mechanism 18, transfers the unthreshed 
crop material from the header 32 to the inlet end of the threshing and 
separating mechanism 18 and comprises a plurality of endless chains or 
belts 80 entrained around a rear drive cylinder 82 and a front supporting 
cylinder 84, shown in phantom in FIG. 1. The upper end of the crop 
elevator 34 is shown fragmentarily in FIG. 2 and depicts a plurality of 
cross bars 86 supported between the chains 80. The unthreshed crop 
material is conveyed in the directions shown by the arrows in FIGS. 1 and 
2 to a feed ramp 88 on the inlet end of threshing and separating mechanism 
18 under the feed means 78. 
The various components of the combine 10 are driven from a conventional 
internal combustion engine 90 mounted on the mobile frame 12 above the 
threshing and separating mechanism 18 by suitable drive means generally 
well known in the art. 
IMPROVED ROTOR 
As mentioned earlier, the rotors 72 are rotatably and concentrically 
mounted within the respective casings 54. Conventional drive means are 
arranged to transmit rotary motion from the engine 90 to both rotors so as 
to drive the same in opposite directions downwardly at their adjacent 
sides (see FIG. 4). Each of the rotors 72 are substantially identical 
except for adaption to rotating in opposite directions and therefore only 
the details of construction of the left rotor 72, as shown in FIGS. 1, 2 
and 3 will be described. Here, it should be again pointed out that 
although the preferred form of the present invention is incorporated in a 
combine having two side-by-side threshing and separating units, the 
invention is equally applicable to a single threshing and separating unit. 
The rotor 72 has a front threshing section and a rear separating section 
and basically comprises a longitudinally extending main body portion 92 
having front and rear stub shafts 74,76 mounted within the main body 
portion 92 and projecting outwardly of respective opposite ends. The main 
body portion 92 is preferably of a generally cylindrical shape and has a 
generally constant outside diameter throughout its length. The term 
"generally cylindrical" as applied to the rotor main body portion 92 is 
intended to cover a rotor shape approaching cylindrical, such as 
polygonal. 
The threshing section of the rotor 72 preferably comprises two 
diametrically opposed threshing elements 94 mounted on the peripheral 
surface of the main body portion 92 and extending longitudinally 
therealong, generally parallel to the axis of the rotor 72. Each threshing 
element 94 includes a rasp bar 96 having rasps 98 and being bolted to the 
top surface of a generally channel-shaped support member 100 with flanged 
edges which is secured by suitable means to the surface of the main body 
portion 92 of the rotor 72 such that the rasp bars 96 are spaced from the 
periphery of the rotor body portion 92. The rasps 98 are inclined or 
skewed with respect to the longitudinally axes of the rotor 72 in such a 
manner that they impart a rearwardly directed axial movement to the crop 
material during operation. Each of the rasp bars 96 have been shown as a 
one-piece construction; however, they could just as readily be formed of 
multiple parts. 
The forward portion of the threshing elements 94 are inclined outwardly and 
rearwardly from the main body portion 92 of the rotor 72 to thereby 
provide a rearwardly-tapering or thinning space 102 (FIG. 2) adjacent the 
inlet end of the threshing and separating unit 20 between the rotor 72 and 
the respective threshing concave 56. The purpose of the thinning space 102 
will be discussed in more detail further on. The rear portion of the 
threshing elements 94 is generally parallel to the axis of the rotor 72. 
The distance between the front end of the threshing element 94 and the 
front end of the threshing concave 56 is greater than the distance between 
the rear end of the threshing element 94 and the rear end of the threshing 
concave 56. 
As seen in FIG. 2, the thinning space 102 provides a definite thinning of 
abnormal bunches or rope-like masses of crop material at the inlet end of 
the threshing and separating mechanism 18. The crop material is moved 
substantially in an axial direction by the feed means 78 rearwardly to the 
forward end of the thinning space 102 where the latter has its maximum 
height. There, the material is engaged by the rasp bars 96 of the rotor 72 
and moved circumferentially with the casing and progressively rearwardly 
along the forward rasp bar portions which converge toward the casing. Such 
movement of the abnormal masses effectuates gradual thinning out of the 
material into a mat having a generally uniform thickness which results in 
substantial and marked improvement in the operation of the combine 10 by 
minimizing or eliminating the thumping caused by the masses and reduces or 
eliminates the damage to the rasp bars 96 and concaves 56. Further, this 
thinning space 102 allows for a more even and constant layer of crop 
material to be directed through the casing 56, thereby resulting in less 
power consumption to operate the threshing and separating mechanism 18 and 
additionally, in the saving of kernels or grains of crop material from 
becoming cracked as a result of abnormally large bunches of crop material 
being fed to the small clearance between the rotor 72 and associated 
concave 56. 
Now, referring again to FIG. 3, the separating section of the rotor 72 
includes a generally cylindrical main body portion 104, which in the 
preferred embodiment is an extension of body portion 92, extending the 
length of the separating section with preferably two separating elements 
or blades 106 extending radially outwardly and longitudinally along the 
main body portion 104. The separating blades 106 are in alignment with the 
threshing elements 94 and are mounted in a similar fashion such that the 
outer surface of each separating blade 106 is coplanar with the outer 
surface of a respective threshing element. As the crop material moves from 
the threshing section into the separating section, the separating blades 
106 sweep the crop material across the separating grates 64 to separate 
the grain remaining therein. The straw, or discardable material, is then 
discharged through the rear of the mechanism 18 where it is discharged 
rearwardly of the combine 10 by the discharge means 30. 
Mounted on the front stub shaft 74 of each rotor 72 is a feed means or 
auger 78 which rotates therewith. The feed means 78 comprises a base 
portion 108 of generally cylindrical shape conforming to the shape and 
diameter of the main body portion 92 of the rotor 72 and auger flights or 
flighting 110 so arranged to feed crop material rearwardly to the inlet 
end of the threshing and separating mechanism 18 as the rotor 72 is 
rotated. The auger flighting 110 preferably includes double helical 
members having a diameter substantially equal to the diameter of the 
circle described by the rear portion of the threshing elements 94 upon 
rotation of the rotor 72. Although the feed means 78 has been shown and 
described in the present embodiment as an auger of a more or less uniform 
diameter, the feed means 78 could be of the conical auger type wherein the 
flighting is larger in diameter at its forwardmost portion and 
progressively decreases in diameter rearwardly toward the threshing 
section of the rotor 72. 
It will be appreciated from the foregoing that the present invention 
provides a single but highly effective thinning space 102 at the inlet of 
threshing and separating mechanism 18 where any abnormal masses, bunches 
or rope-like formations of crop material may be thinned or somewhat 
smoothed out incident to having the direction of movement thereof abruptly 
changed from generally axial to substantially circumferential prior to the 
material being introduced to the more confined major or principal 
threshing section of the threshing and separating mechanism. Such results 
in the benefits of savings in power consumption, minimal wear upon the 
components of the threshing elements, and otherwise in improved threshing 
operations performed by the combine. 
While the invention has been described and illustrated in its several 
preferred embodiments, it should be understood that the invention is not 
to be limited to the precise details herein illustrated and described 
since the same may be carried out in other ways falling within the scope 
of the invention as illustrated and described.