Header for harvesting machine

A header for a harvesting machine having a frame, a cutterbar operable to a cut standing crop and mounted on the front of the frame, and a reel also mounted on the frame and operable to sweep crop material towards and over the cutterbar, the cutterbar being adjustable relative to the frame in a fore-and-aft direction, is disclosed wherein the header includes an interlock mechanism extending between the reel and the cutterbar such that the position of the reel relative to the cutterbar is automatically adjusted upon the fore-and-aft movement of the cutterbar to maintain a substantially constant reel-cutterbar spacing.

BACKGROUND OF THE INVENTION 
This invention relates generally to crop harvesting headers attachable to 
combines and, more particularly, to an interlock mechanism interconnecting 
the reel and a fore-and-aft adjustable cutterbar. 
Typically, a header for a harvesting machine includes a cutterbar which is 
operable to cut standing crop as the machine moves forward and a rotatable 
reel which carries tines to engage the standing crop and sweep it towards 
the cutterbar for cutting and then carry the cut material towards an auger 
before releasing it. The auger usually consolidates the cut crop material 
centrally of the header before it is passed to the body of the machine for 
processing. The relationship between the cutterbar and the auger is 
critical and in general depends on the type and condition of the crop to 
be harvested. When harvesting down crops, i.e., crops that are not 
standing in a normal upright position, the relationships between the reel, 
the cutterbar and the auger is equally critical and, in general, the reel 
should be disposed so that the path described by the outer ends of the 
tines first enters below the level of the cutterbar forwardly thereof for 
lifting down crop, then sweeps closely over the cutterbar and finally 
passes in close proximity along the auger. 
Headers are known in which the cutterbar is vertically flexible along its 
length so that it can follow local irregularities in the ground. With such 
headers, it is necessary to be able to adjust the height of the reel 
relative to the highest point of the cutterbar at any given instant, 
otherwise the cutterbar is likely to foul the reel on flexing with 
consequential damage to one or both components. To this end, headers 
having flexible cutterbars have been fitted with means for automatically 
adjusting the position of the reel on vertical flexure of the cutterbar. 
Headers, such as shown in U.S. Pat. No. 4,011,709, have been provided to 
render the cutterbar adjustable in a generally fore-and-aft direction so 
that the spatial relationship between the auger and the cutterbar can be 
selectively chosen dependent on the type and condition of the crop to be 
harvested. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a header with a 
fore-and-aft adjustable cutterbar to suit various crops and crop 
conditions and which is not afflicted with the risk of reel/cutterbar 
interference upon adjustment of the cutterbar. 
It is a feature of the instant invention to maintain at least the minimum 
clearance between the reel and the cutterbar substantially constant in 
response to the fore-and-aft movement of the cutterbar. 
It is another object of the present invention to provide a header for a 
harvesting machine having an interlock mechanism extending between the 
reel and the cutterbar for automatically adjusting at least the minimum 
reel/cutterbar spacing upon fore-and-aft adjustment movement of the 
cutterbar whereby interference between the reel and the cutterbar during 
said adjustment movement is avoided. 
It is an advantage of this invention that the interlock mechanism 
automatically adjusts at least the minimum reel height relative to the 
cutterbar upon generally fore-and-aft adjustment of the cutterbar. 
It is another feature of this invention that the interlock mechanism may 
comprise a linkage mechanism at each side of the header and extending 
between the cutterbar and a hydraulic actuator which is operable to effect 
general adjustment of the reel via an arm, two such arms rotatably 
carrying the reel therebetween. 
It is another advantage of this invention that each linkage may comprise a 
series of links, including a bell crank lever. 
It is still another advantage of this invention that the interlock 
mechanism may comprise a hydraulic slave cylinder acting between the 
cutterbar and the header frame so that, as the cutterbar is adjusted, the 
length of the slave cylinder changes and the resulting oil displacement is 
used to control main hydraulic actuators operable to adjust the position 
of the reel. 
It is another feature of this invention that adjustment of the position of 
the reel will normally be generally vertically, but may nevertheless 
include a fore-and-aft (i.e., generally horizontal) component to this reel 
movement.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring first to FIG. 1, the header of the first embodiment is basically 
conventional in that it comprises a frame 1, a cutterbar 2 mounted on the 
frame, an auger 3 mounted in an auger trough 4, and a reel 5 mounted for 
rotation between the forward ends of a pair of reel arms 6, the other ends 
of which are pivotally attached at 7 to the frame 1 in order that the reel 
can be raised and lowered by hydraulic actuators 10 (FIG. 7) which act 
between the arms and the frame. The reel 5 carries tine bars 8 fitted with 
tines 9 which are arranged to maintain a fixed orientation as the reel 
rotates, in a conventional manner. The outer tips of the tines 9 describe 
a circular path 11, when the header is operating in down crops, the reel 5 
is positioned as close as possible to the cutterbar 2 in order to optimize 
the cooperation between the reel and cutterbar. More specifically the 
arrangement is such that the tine path 11 extends as close as possible to 
the ground forwardly of the cutterbar 2 to lift down crop for presenting 
it to the cutterbar 2 to pass crop to the auger 3 for consolidation 
centrally of the machine for passage through a central opening (not seen 
in the drawings) in the rear wall 13 of the header for processing by a 
conventional combine harvester (not shown) to which the header is, in use, 
fitted. 
Depending on the nature and condition of the crop to be harvested, the 
cutterbar 2 has to be adjusted relative to the auger 3. In accordance with 
the present invention, the cutterbar is adjustable in a generally 
fore-and-aft direction of the machine for which the header is intended. 
Referring now to FIGS. 1-5, the cutterbar 2 comprises a plurality of knife 
guards 14 which are bolted on a flange 16 of a hollow transverse beam 17, 
as best seen in FIG. 3. Attached to the rear face of the beam 17 at spaced 
intervals therealong, via plates 18, are a plurality of inner ones 19 of 
pairs of telescopic members 19,21, the outer members 21 being attached to 
respective curvilinear frame members 22. The frame members 22 are of 
inverted U-section with this section being closed by plates 23 (FIG. 4) at 
the portions attached to the outer telescopic members 21. The pairs of 
telescopic members 19,21 have a cross-sectional shape in the general form 
of a lemon (as seen in FIG. 3) these being readily available components 
having the necessary structural strength and sliding characteristics but 
components of other cross-sectional shape may, of course, be employed. It 
will be seen from FIG. 3 that the telescopic members 19,21 are not 
co-extensive, the inner members 19 extending beyond the outer members 21 
and being connected at their rear ends to generally L-shaped brackets 24 
which themselves extend between and are connected to adjacent ends of the 
rear edges 25 of shows 15. Individual shoes 15 extend in between adjacent 
pairs of telescoping members 19,21. These shoes 15 are secured to the beam 
17 of the cutterbar 2 at their forward edges and have rear edges which are 
turned up to form U-channels 25 for reinforcing said shoes. 
Depending on the width of the header, preferably three or five shoes 15 are 
provided, which means that also four, respectively six pairs of 
telescoping members 19,21 are provided. The shoes 15 together form a 
ground contacting surface for the header which extends substantially 
across the full width thereof; the facing edges of the individual shoes 15 
being positioned generally at the location of the corresponding 
telescoping members 19,21. The cutterbar 2, with the beam 17, the inner 
telescoping members 19, the L-shaped brackets 24 and the shoes 15 together 
thus form a rigid structure which is fore-and-aft adjustable relative to 
the header auger 3. 
Reinforcing profile members 20 and 30 are welded to the upper surface of 
each shoe 15; the member 20 extending generally parallel to the 
corresponding U-channel 25 and the member 30 extending generally in the 
fore-and-aft direction between the respective U-channel 25 and the 
corresponding transverse member 20 generally midway of the width of the 
shoe 15. 
The bottom of each U-channel 25 carries a bracket 26 generally in alignment 
with the corresponding reinforcing member 30. Reinforcing L-shaped ribs 27 
are provided on the upper surface of the shoes 15 and are disposed to 
slidingly engage with the lower edges of the U-shaped frame members 22 
when the shoes 15 are deformed slightly under the weight of the header 
when supported on the ground. The L-shaped ribs 27 further also have a 
sealing function to prevent the ingress of dirt into the space above the 
shoes 15. 
Each bracket 26 carries a lug 28 which is received between the bifurcated 
end 29 of one half or limb 31 of a wishbone-shaped linkage 32 as best seen 
in FIG. 2, the linkage 32 acting as actuating means for fore-and-aft 
adjustment of the cutterbar 2. As one linkage 32 is associated with each 
shoe 15, there preferably are provided in total respectively three or five 
such linkages 32 depending on the width of the header. The linkage half 31 
is pivotally connected to the bracket 26 by a pivot pin 33, and one end of 
the other limb or half 34 of the linkage 32 receives a pivot pin 35 which 
is connected via a bracket 36 to a transverse tubular member 37 forming 
part of the header frame 1. 
The two halves 31,34 of each linkage 32 are pivotally connected together by 
a pivot pin 38. The adjacent ends of the linkage halves 31,34 are both 
bifurcated with the end of half 34 receiving the end of half 31 which in 
turn receives a flat connecting link 39 through which the pivot pin 38 
also passes. Except for the two extreme stirrup links 32 (of which one is 
seen at the top right of FIG. 2), the links 39 extend to either side of 
the pivot pins 38 to receive the flattened ends of individual tubes 40 
which, in combination with the links 39, make up a drive rod which serves 
to operate all of the linkages 32 simultaneously. It will be remarked that 
the linkages 32 and the coupling members 39,40 extending therebetween 
merely act as adjustment synchronization means to the extent that these 
components do not have to take up any vertically oriented forces of any 
significance such as the weight of e.g., the cutterbar 2 and the shoes 15, 
which is beneficial for the accuracy of the synchronization of the 
adjustment. In other words, this is beneficial to ensure that, during 
fore-and-aft adjustment, the cutterbar 20 is moved in perfect parallel 
relationship with its initial position, whereby jamming of the telescoping 
members 19,21 is avoided. 
Adjacent one of the end linkages 32, which is seen at the top right of FIG. 
2, there is mounted a drive mechanism 50 which initiates adjusting 
movement of the cutterbar 2 relative to the header frame 1. This drive 
mechanism 50 alternatively may be provided adjacent the middle one of the 
linkages 32 so as to improve even further the adjustment synchronization. 
This drive mechanism 50 is shown in greater detail in FIG. 5 and comprises 
a threaded spindle 41 fitted with an hexagonal head 42 at its outer end 
for engagement by a correspondingly shaped box spanner 43 fitted to one 
end of a handle 41. The spindle 41 passes through an aperture in a flange 
45 of a bracket 46 attached to the frame tube 37 and is prevented from 
undergoing axial movement relative to the bracket 46 by two bushes 47 and 
48 disposed on either side of the flange 45 and separated by thrust 
washers 49 and 51. The bush 47 is welded to the spindle 41 and the bush 48 
is attached thereto by two bolts or screws 60. The spindle 41 is received 
by a correspondingly threaded nut 52 which is welded to a flange 53 which 
in turn is bolted to the bottom wall of the U-channel 25 of the adjacent 
shoe 15. 
Referring now to FIG. 6, the drive for the cutterbar 2 is illustrated and 
this is a belt drive arrangement, whereby it is necessary to make 
provision in this drive line for movement of the cutterbar when the latter 
is adjusted. A drive pulley 54 is rotatably mounted on the frame 1 and 
thus does not move with the cutterbar 2. A belt 55 extends around the 
drive pulley 54 and around a tension pulley 56, an idler pulley 57, a 
pulley 58 on a conventional wobble box 59 which converts the rotary drive 
to a reciprocable drive for the cutterbar 2, and a further idler pulley 
61. The wobble box 59 is mounted on the header for movement together with 
the cutterbar 2 in a fore-and-aft direction relative to the header frame 
1. The two idler pulleys 57 and 61 are connected to the wobble box 59 by 
respective arms 62 and 63, the arms being pivotally connected to both the 
wobble box and respective stub shafts 64 and 65 of the associated pulleys. 
The stub shaft 64 of the idler pulley 57 slidably engages a curved slot 66 
in a plate 67 attached to a side sheet (not shown) of the header. The stub 
shaft 65 slidably engages a curved slot 68 provided in a plate 69 also 
attached to the associated side sheet. Also shown in FIG. 6 is a 
conventional slip clutch 71 for the auger 3 and it is the presence of this 
component which dictates the arm and slot arrangements (62,66; 63,68) 
which could otherwise be simplified. 
The full line position of the components illustrated in FIG. 6 is that 
adopted when the cutterbar 2 is in its fully retracted position, with the 
idler pulleys 57 and 61, the wobble box 59 and the arms 62 and 63 also 
being shown in phantom in the fully extended position of the cutterbar 2. 
It will be seen that the wobble box 59 moves with the cutterbar 2 taking 
with its the arms 62 and 63, whereby the stub shafts 64 and 65 are pulled 
along the respective slots 66 and 68, thus moving the idler pulleys 57 and 
61 to new positions. It will be seen that the movement of the idler 
pulleys 57 and 61 is such as to maintain the path length of the belt 55 
substantially constant, whereby drive to the cutterbar 2 is not disturbed 
on cutterbar adjustment. 
Turning now to FIG. 7, this illustrates the present invention, namely an 
interlock 70 between the reel 5 and the cutterbar 2 which prevents 
interference between the reel tines 9 and the cutterbar 2 upon adjustment 
of the cutterbar 2 in a forward direction. Such interference indeed could 
occur if no precautions were taken due to the fact that the cutterbar 2 is 
adjustable in a plane intersecting with the tine path 11 of the reel 5 
when the latter is in its lowermost position, this plane being oriented 
slightly upwardly as seen in a forward direction. The reason for all this 
being that the reel tines 9 of the cutterbar 2 when the reel 5 is adjusted 
for harvesting down crops. Preferably, the reel tines 9 even should reach 
below the level of the cutterbar 2 when the reel 5 is adjusted for 
harvesting down crops. Preferably, the reel tines 9 even should reach 
below the level of the cutterbar at said location and under said 
condition. Consequently, under these circumstances there could be 
interference between the cutterbar 2 and the reel tines 9 when the 
cutterbar 2 is extended. This inevitably would result in damage to the 
reel tines 9 in the first place, but eventually also to the cutterbar 2 in 
case the reel tines 9 are made of spring steel, as is conventional, rather 
than of synthetic material (plastic) as has been proposed in recent years. 
The interlock 70 according to the present invention prevents this by 
raising the reel 5 upon adjustment of the cutterbar 2 in the forward 
direction. Similarly, the interlock 70 also lowers the reel tine path 11 
when the cutterbar 2 is retracted so as to maintain the vertical clearance 
between said path 11 and the cutterbar 2 substantially constant. 
The interlock 70 comprises a linkage system which interconnects each 
hydraulic actuator 10 (which at each side of the header) and the cutterbar 
2. Each linkage system comprises a short link 72 pivotally attached at one 
end to the associated hydraulic actuator 10 and rigidly coupled at the 
other end to one end of a longer link 73. The links 72,73 thus together 
form a cranked lever which is pivotally mounted on the associated header 
sidewall at 80. The other end of the link 73 is pivotally coupled to one 
end of another short link 74, the other end of the latter in turn being 
pivotally attached to one end of a link 75 which itself is fixed to the 
beam 17 carrying the cutterbar 2. 
When the cutterbar 2 is adjusted from the fully retracted (full line) 
position of FIG. 7 to the extended (phantom) position, the crank lever 
72-73 of each linkage system is pivoted around pivot 80, thus imparting a 
lifting to the associated actuator 10 relative to the header, whereby the 
related reel arm 6 (and hence reel 5) is lifted to the position shown in 
phantom in FIG. 7. It will be seen from FIG. 7 that the relative vertical 
position of the reel 5 with its cylinders 10 fully retracted and the 
cutterbar 2 is maintained substantially constant on adjustment of the 
cutterbar. It will also be seen that the relative horizontal position of 
the reel 5 with its cylinders 10 fully retracted and the auger 3 equally 
is maintained substantially constant on adjustment of the cutterbar 2. 
It will be appreciated by those skilled in the art that the foregoing 
characteristics preferably are combined with the reel adjustments already 
known in the art. Indeed, the reel 5 also may be lifted at a substantial 
height above the cutterbar 2 for harvesting standing crop by actuating the 
hydraulic cylinders 10 whereby the reel arms are pivoted in a clockwise 
direction as seen in FIG. 1 around pivot 7. When the reel is in such a 
raised position there is, of course, no risk for interference between the 
reel tines 9 and the cutterbar 2 and thus the action of the interlock 70 
is beneficial only for cutterbar adjustment when the reel cylinders 10 are 
in their retracted position. 
The reel 5 further also may be adjustable in a fore-and-aft direction by 
making it shiftable relative to the reel arms 6. Fore-and-aft reel 
adjustment is generally known in the art and is effective to vary the 
relative horizontal position between the reel 5 and the auger 3 on the one 
hand the reel 5 and the cutterbar 2 on the other hand. The interlock 70 
between the reel 5 and the cutterbar 2 remains operative irrespective of 
the relative fore-and-aft position of the reel in the event fore-and-aft 
reel adjustment means are provided. 
Returning now to FIGS. 1 to 6, the cutterbar 2 is adjusted by taking the 
handle 44 and engaging the head 42 with the box spanner end 43 of the 
handle. The handle is then actuated to rotate the spindle 41 in the 
required direction, according to whether the cutterbar 2 is to be extended 
or retracted. For present purposes of description, it will be assumed that 
cutterbar extension is required, whereby the spindle 41 is rotated to move 
the nut 52 to the left (as seen in FIG. 5) and take with it the associated 
shoe 15 and hence the cutterbar 2 which is attached thereto, the inner 
members 19 of the telescopic members 19,21 associated with said shoe 
sliding within the corresponding outer members 21. Movement of the shoe 15 
associated with the drive mechanism 50 in this manner will initially pull 
apart the halves 31,34 of the wishbone linkage 32 immediately adjacent the 
spindle 41. Since the linkage half 34 is pivotally coupled to the fixed 
frame member 37, separation of the two halves 31,34 pulls the 
interconnecting pivot 38 to the right (as seen in FIG. 2), whereby the 
drive rod made up of the links 39 and tubes 40 also is pulled to the 
right, thus opening all of the other wishbone linkages 32 and thus 
effecting the same adjustment movement of the corresponding shoes 15 along 
the entire length of the cutterbar 2 resulting in a corresponding 
adjustment of the cutterbar 2. 
It will be appreciated that, on extension of the cutterbar 2 in the 
fore-and-aft direction of the machine to which the header is fitted, the 
inner members 19 of the telescopic members 19,21 are pulled out of the 
outer members 21. In order to maintain a solid floor to the auger trough 
4, plates 76 are attached to the beam 17 which are slidable over plates 77 
(FIG. 5) attached to the frame 1 and forming the main floor of the auger 
trough 4. Preferably these plates 76 are made of resilient sheet material 
and are shaped and positioned to resiliently engage the plates 77 in 
overlapping relationship. 
As already described, the drive to the cutterbar 2 remains effective during 
cutterbar adjustment by virtue of the idler pulleys 57 and 61 and arms 62 
and 63, and interference of the idler pulleys 57 and 61 and arms 62 and 
63, and interference between the cutterbar 2 and the reel tines 9 is 
avoided by virtue of the interlock 70 shown in FIG. 7. 
Thus the present invention provides a header with a cutterbar which is 
adjustable generally fore-and-aft of the machine to which the header is 
fitted, this adjustment automatically altering the position of the reel 
relative to the cutterbar by virtue of the provision of the interlock 
mechanism between these two components whereby interference between these 
two components, upon fore-and-aft adjustment of the cutterbar, 
automatically is avoided. It will also be understood by one skilled in the 
art that an automatic adjustment of the reel position in response to the 
fore-and-aft movement of the cutterbar is particularly important under 
circumstances where the cutterbar movement can be accomplished on the go, 
i.e., during operation of the combine. Such an operation can be had by 
utilizing a remotely controlled rotary actuator operably connected to the 
spindle 41. 
It will be understood that changes in the details which have been described 
and illustrated to explain the nature of the invention will occur to and 
may be made by those skilled in the art upon a reading of this disclosure 
within the principles and scope of the invention. As an example, it will 
be appreciated that the interlock mechanism 70 may be disposed between the 
cutterbar 2 and the pivot 7 for the reel arms 6, whereby cutterbar 
movement results either in rotation of the reel arms 6 about the pivot 7 
or shifting of the reel arm pivot axis 7 itself so as to maintain a 
substantially constant reel/cutterbar gap. It will be appreciated that 
linkage mechanisms other than those illustrated in the drawings may be 
employed in the interlock arrangement. Furthermore, the interlock 
mechanism may be hydraulic; for example, a slave cylinder may be provided 
between the cutterbar 2 and the header frame 1 so that, as the cutterbar 
is adjusted, the length of the slave cylinder changes and the resulting 
oil displacement is used to control the main actuators 10 so as to raise 
or lower the reel 5, as appropriate. 
It will be noted that, with the interlock mechanism 70 as described in 
detail and with the alternatives briefly mentioned herebefore, the reel 
position is varied upon adjustment of the cutterbar irrespective of what 
the initial reel/cutterbar spacing is, i.e., the reel is repositioned also 
when the reel is in a raised position for harvesting upright crops. 
Although repositioning of the reel under these circumstances is not 
required for any reason, it also has no adverse effect on the operation of 
the header. It will be noted that it is essential to adjust the reel 
position relative to the cutterbar upon fore-and-aft adjustment of the 
latter only when the reel is in close proximity to the cutterbar as only 
then risks for interference exist. Accordingly and although the embodiment 
shown in FIG. 7 is the preferred embodiment for reason of its simplicity, 
it is equally useful to provide an arrangement wherein the reel position 
relative to the cutterbar is adjusted in response to fore-and-aft 
cutterbar adjustment only when the reel is positioned with its tine path 
in the immediate vicinity of the cutterbar. In other words the interlock 
mechanism according to the invention may control the minimum reel height 
relative to the cutterbar upon fore-and-aft cutterbar adjustment and 
remain inoperative during fore-and-aft cutterbar adjustment when the reel 
is positioned at a substantial height above the cutterbar for harvesting 
upright crop. 
This may be accomplished by providing adjustable stops for the reel arms 
which prevent lowering of the reel below a given minimal spacing above the 
cutterbar, these stops being adjustable in response to fore-and-aft 
cutterbar adjustment by an interlock mechanism of the type disclosed in 
FIG. 7. This interlock mechanism operatively couples the stops with the 
cutterbar in a manner to raise these stops when the cutterbar is adjusted 
in the forward direction and vice versa. 
When, during operation, the reel supporting cylinders 10 are fully 
retracted whereby the reel arms rest on said stops and the cutterbar is 
extended resulting in a lifting of the stops, a corresponding raising of 
the reel together with said stops is obtained. To facilitate this it may 
be necessary to telescopingly couple the plunger rods of the reel 
cylinders to the reel arms whereby these reel arms can be pivoted upwardly 
without the plungers having to follow this movement whereby it is 
prevented that a vacuum is formed below the plungers when the reel is 
lifted relative to the reel cylinders which in turn could cause problems 
by the introduction of air into the hydraulic system.