Forage harvester

A self-propelled forage harvester having a longitudinally extending mobile frame supported by forward and rearward pairs of transversely spaced wheels. A cutterhead unit is mounted on the forward portion of the frame and includes a housing having a rear crop outlet. Within the housing a shear bar is mounted adjacent the path of the knives of a transverse cylindrical cutterhead rotatably mounted in cooperative relationship with the shear bar for cutting crop material fed thereto. Mounted on the frame rearwardly of the cutterhead unit is a blower unit with a housing having a crop inlet aligned with the crop outlet of the cutterhead unit. The blower includes blades rotating within the housing in a generally circular path about an axis inclined forwardly and upwardly to permit the lower limit of the circular path of the blades to be disposed forward of the upper limits of the path.

BACKGROUND OF THE INVENTION 
The present invention relates generally to crop harvesting machines and 
more particularly to a new and improved forage harvester machine. 
The well known agricultural practice of forage harvesting consists of 
cutting either green or mature crop material into discrete particles and 
conveying them from the field to a storage silo where they undergo an acid 
fermentation to give them an agreeable flavor and to prevent spoilage. 
This operation, which is commonly referred to as an ensilage process, 
converts standing crop in the field to livestock feed, commonly referred 
to as silage. An essential piece of farm machinery used for producing 
silage is the forage harvester which is adapted to gather crop material 
from the field, cut it into small particles and then convey the cut crop 
material to a temporary storage bin or wagon. Harvesters of this type are 
either self-propelled or pulled by a tractor. Typically, forage harvesters 
have a rotary cutter of a generally cylindrical configuration with knives 
peripherally mounted to cooperate with a fixed shear bar for cutting 
material as it is passed across the surface of the bar. An optical 
perforated recutter screen is used under some conditions to reduce the 
size of the cut crop even further when desirable. 
Many forage harvesters are provided with a blower to convey the cut crop to 
a wagon towed behind or along side the harvester for receiving the crop. 
In some prior art arrangements, cut crop material is transferred to the 
blower from the cutterhead by intermediate conveyor means such as an auger 
system. Single or side-by-side augers are used at right angles or parallel 
to the axis of the rotary cutter. Problems have been encountered in some 
instances with this type of mechanism when material accumulates unevenly 
along the augers and causes clogging. From a design standpoint, augers 
provide extra moving parts that are subject to wear and thereby reduce 
overall reliability and serviceability characteristics of the harvester. 
Furthermore, use of augers increases the power requirements of the 
harvester especially in crop material having high moisture content. 
To overcome problems of this nature some prior art forage harvesters have 
been designated with cutterhead discharging material directly to the 
blower without intermediate conveying means. In these direct discharge 
machines the blower fan rotates about an axis horizontal to the ground. 
The blower unit receives material fed from the cutterhead directly to the 
fan blades which in turn convey the cut crop material upwardly through a 
spout and thence to a bin or wagon. To properly accommodate direct feed 
type upright blowers the blower spout, the operator's platform or other 
important components are undesirably offset from the path of travel in 
prior art self-propelled harvesters. This offset has been necessitated to 
provide proper clearance for the spout with respect to the many other 
bulky components of the harvester such as the engine, an operator's 
platform positioned to permit proper visibility, power transmission 
mechanisms, a fuel tank of a sufficient size to permit long periods of 
field operation, etc. 
SUMMARY OF THE INVENTION 
Accordingly, it is a principal object of the present invention to provide a 
forage harvester having its operative components uniquely arranged in a 
simple, efficient and economical manner. 
A more particular object, taking into consideration the presence of 
propulsion mechanisms and other required operating components on a 
self-propelled forage harvester, is to provide an improved combination of 
components which cooperatively operate in a manner not heretofore known. 
In pursuance of these and other objects, the present invention contemplates 
new and improved forage harvester apparatus in which the blower unit is 
uniquely positioned in relation to other components to improve the overall 
efficiency and effectiveness of the harvester while permitting various 
other related advantages conducive to significant advances in the practice 
of forage harvesting. 
In one embodiment the forage harvester comprises a longitudinally extending 
mobile frame supported by at least a pair of transversely spaced wheels. A 
cutterhead unit is mounted on the forward portion of the frame and 
includes a housing having an outlet for discharging cut crop rearwardly. 
Disposed within the cutterhead unit is a transverse shear bar in 
cooperative relationship with a generally cylindrical cutterhead for 
cutting crop material fed by a feeder mechanism mounted on the forward 
portion of the frame. Mounted rearwardly of the cutterhead is a blower 
unit including a housing having a crop inlet in communication with the 
outlet in the cutterhead unit. A fan is mounted in the blower housing 
having two or more blades rotatable about a generally longitudinal axis 
for blowing crop material upwardly and away from the forage harvester 
machine. The present invention particularly contemplates a blower mounted 
with its axis inclined upwardly and forwardly whereby the fan blades have 
paths of rotation extending below the cylindrical cutterhead to minimize 
the distance between the forwardly mounted shear bar and the fan to 
enhance the overall performance of the forage harvester. In those 
instances where a recutter screen is included among the components of the 
forage harvester the blower position of the present invention is 
especially advantageous as will become apparent from the following 
description. 
The foregoing and other objects, features and advantages of the invention 
will appear more fully hereinafter from a consideration of the detailed 
description which follows, in conjunction with the accompanying sheets of 
drawings wherein one principal embodiment of the invention is illustrated 
by way of example. It is to be expressly understood, however, that the 
drawings are for illustrative purposes and are not to be construed as 
defining the limits of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
In the following description, right-hand and left-hand references are 
determined by facing the direction of travel of the forage harvester 
machine. 
Referring to the drawings for a detailed description, a self-propelled 
forage harvester, generally designated by reference numeral 10, is shown 
in FIG. 1 to illustrate by way of example one type of equipment in which 
the present invention is embodied. The forage harvester 10 comprises a 
plurality of operative components mounted on a generally longitudinally 
extending frame 11 supported at its forward end by a pair of transversely 
spaced wheels 12 (only one shown, FIG. 1) and supported rearwardly by a 
pair of transversely spaced wheels 13 (only one shown, FIG. 1). 
The frame comprises several integral members including opposing rear 
members 14 having forward ends terminating in a cross member 15. A pair of 
opposing forward members 16, 17 extend from cross member 15 with 
intermediate cross strut 18 and forward cross strut 20 completing the 
basic longitudinally extending frame. Mounted on the forward portion of 
the frame is a cutterhead unit 21 and just rearwardly thereof is a blower 
unit 22, both of which are directly below an operator control unit 23 in 
the form of an enclosed cab extending upwardly from a supporting platform 
24. Operator control unit 23 is supported in a cantilever fashion by a 
pair of opposing support members 25,26 affixed to and extending upwardly 
and forwardly from frame cross member 15. Intermediate support members 27 
are interposed between opposing forward members 16, 17 and cab support 
members 25,26. 
Completely the general arrangement of typical components in forage 
harvesters of the self-propelled type is power unit 28 and associated fuel 
tank 30 (both shown in phantom) mounted within the general enclosure 
configuration rearwardly of the operator control unit 23. The power unit 
is drivingly coupled to the cutterhead unit and the blower unit and 
propels the harvester via means commonly known in the art including but 
not limited to transmission means, clutching means, drive reversing means, 
etc. Power and drive components are only schematically shown and are not 
meant to accurately depict a complete operative system. For example, a 
shaft 31 is simply shown as extending forwardly from power unit 28 to 
drive blower unit 22, whereas in practice it is common to utilize a 
reversing mechanism for the cutterhead and blower drives which would 
necessarily modify this direct connection. 
Also shown in FIG. 1 is a rearwardly and upwardly extending spout 32 for 
conveying material away from the harvester, a spout support arm 33 
extending from the roof of control unit 23, and cutterhead components 
mounted within side walls 35,36 (see FIG. 2) of a housing 34, including 
feeder mechanism 37, a shear bar assembly 38, a transfer chute 40 and a 
cutterhead 41. 
More specifically, blower unit 22 includes a housing 42, transition 43 and 
spout 32. Within the housing a fan 44 is rotatably mounted for rotation 
about a shaft 45 which is inclined upwardly and forwardly. The inclined 
position of the blower unit is the very essence of this invention. Among 
other things, it provides improved operational relationship of the 
components of the harvester while enhancing the physical relationship. For 
example, spout 32 is disposed to clear platform 24 of the operator control 
unit 23 while permitting the lower end of the path of travel of the fan to 
extend below and forward of the rearmost portion of the path of travel of 
the cutterhead. This important relationship will be described in detail 
hereinbelow. 
Now turning to FIGS. 2 and 3 where the components of cutterhead unit 21 are 
shown in detail, a cutterhead 41 of a conventional nature is depicted 
comprising a plurality of knives 46 mounted laterally on a series of 
side-by-side plate members 47. Cutterhead 41 rotates via shaft 48 
journalled in side walls 35,36 of housing 34. Drive for the cutterhead is 
provided by a belt (not shown) in cooperative engagement with sheave 50 
(FIG. 2) keyed to shaft 48. The drive for the cutterhead as mentioned 
above is provided by power unit 28, a detailed description of which is not 
essential for the purposes of the present invention. 
The feeder mechanism 37 comprises upper feed rolls 51,52 and lower feed 
rolls 53,54, all of which are mounted for rotation about transverse axes 
in a standard manner between side wall members 35,36. Completing the 
cutterhead unit is shear bar assembly 38 consisting of a transverse 
bracket 55 (FIG. 3) affixed to forward cross strut 20. Secured to bracket 
55 is a support block 56 on which is mounted shear bar 57 which is 
accessible through an opening in the side wall members permitting 
adjustment for precise positioning with respect to the cutting edges of 
knives 46. Adjustment of the shear bar is accomplished in a well known 
manner the details of which are not an essential part of this description. 
Attached to the shear bar assembly is a scraper member 58 mounted forward 
of the shear bar in cooperative relationship with the smooth surface of 
lower feed roll 54. Drive for the feed roll assembly is provided by input 
shaft 60 (FIG. 2) coupled to the power unit in a conventional manner (not 
shown). Motion is imparted to the feed rolls via a universal joint 61 and 
chain and sprocket assembly 62. 
Mounted on frame 11 rearwardly of cutterhead 41 is blower unit 22, referred 
to above. Blower housing 42, secured to intermediate cross strut 18, 
includes a generally cylindrical chamber in which fan 44 is journalled for 
rotation via shaft 45. Fan blades 63 and 64, attached to fan base plate 
65, are adapted to receive crop material through an access opening 66 and 
convey it upwardly and through transition member 43 interposed between 
blower housing 42 and spout 32. The lower portion of blower housing 42 is 
below and foward of the path of travel of the cutterhead knives 46, the 
outline of which is shown in FIG. 3. Drive for fan 44 is provided via 
shaft 31 which transmits rotational force to shaft 45 via a universal 67 
(FIG. 1) coupled to a gear box 68, shown in phantom. 
Chute 40 is provided to guide crop from the cutterhead to access opening 66 
in blower housing 42. This chute, pivotally attached to brackets 70,71 via 
support arms 73,74 includes a transverse support rib 75, side portions 76 
and a base 77 formed to guide material downwardly and rearwardly to the 
opening in the blower housing. Chute 40 is releasably pivotable to an 
access position (shown in phantom in FIG. 3) for cleaning and service 
purposes. In its operative position chute 40 completes the enclosure 
formed by the cutterhead housing and the blower housing thus controlling 
communication between the cutterhead and blower units. 
In operation, harvested crop material is guided to feeder mechanism 37 via 
a header such as a row crop unit or a windrow pickup unit, both of which 
are common in the art. A unit of the row crop type is shown in phantom in 
FIG. 1 for exemplary purposes. Crop material guided between opposing upper 
and lower feed rolls 51,52 and 53,54, respectively, is fed to shear bar 
assembly 38. Shear bar 56 is mounted to cooperate with knives 46 on 
cutterhead 41 to cut crop material in small particles and propel it 
downwardly and rearwardly within the enclosed cutterhead unit via chute 40 
and thence into access opening 66 of blower unit 22. Cut material is 
thereupon engaged by fan base plate 65 and blades 63,64 which in turn 
propel it along a generally circular path and tangentially out through 
transition member 43, then to spout 32 and rearwardly to a trailing wagon 
which is not shown. In other arrangements the spout directs material to a 
wagon alongside the harvester or to a bin mounted on the harvester. 
In some conditions, a recutter screen 78 is used in a conventional manner 
as an integral part of cutterhead unit 21. The screen 78, shown in phantom 
in FIG. 3, has perforations in varying sizes, the edges of which recut 
crop material as it is passed through the screen from the cutterhead to 
the blower. The velocity of material is diminished due to the interposed 
recutter screen. The recutter is only used under certain conditions, such 
as where corn kernels require cracking, or the particle lengths of the cut 
crop material is critical, etc. 
The unique apparatus and particularly the position and relationship of the 
blower unit in the forage harvester discussed above provides many 
advantages. For example, the lower limit of the path of travel of the fan 
blades is forward of the upper limits of the path and the lower portion of 
the opening is under and forward of the periphery of the cutterhead, thus 
enhancing the effectiveness of the blower in that cut crop material is 
received more directly from the shear bar unit and thereby improving 
overall performance without affecting efficiency. Also, the unique 
positional relationship of the blower opening and fan with respect to the 
cutterhead unit improves material flow via a recutter screen (when used) 
which has a natural tendency to impede material passage, i.e., material 
flow is assisted by gravity and the shorter path enhances average crop 
particle velocity. 
Furthermore, the unique combination discussed above provides advantages in 
that cab placement in the center and over the cutterhead in a more 
rearward position improves visibility of the forage harvester operator. 
The blower unit is inclined from a position below operator control unit 23 
to a position to the rear of the cab, whereby the spout clears the lower 
rear portion of platform 24 of the operator control unit via a slight 
cutaway portion behind the control area. This reduces the exit angle of 
transition member 43 with respect to the frame and thereby permits a more 
gradual curvature in the spout to give more efficient delivery of material 
than heretofore experienced. 
A still further and important advantage of the structure of the forage 
harvester apparatus described above is the ability to position the cab or 
operator control unit over the front axle. This provides important weight 
distribution characteristics which are critical in the design of 
self-propelled farm machinery which must be designed to operate in adverse 
field transport conditions. Also, with respect to weight distribution 
characteristics of the machine described is the ability to position the 
blower unit directly under the cab and thus likewise dispose weight over 
the front axle. 
While the preferred structure in which the principles of the present 
invention have been incorporated is shown and described above, it is to be 
understood that the invention is not to be limited to the particular 
details, as shown and described above, but that, in fact, widely different 
means may be employed in the practice of the broader aspects of the 
invention.