Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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HARVESTER EIEADER WITH FLOATING CUTTER BAR
BACKGROUND OF THE INVENTION
Tech_cal Field
This invention relates to the header for a
harvester and more particularly to the construction and
suspension of a floating cutter bar for a harvester
header.
Prior Art
Heretofore, others have provided floating cutter
bars of various types. One such floating cutter bar is
illustrated in U.S. patents 4,206,583 and 4,206,584
wherein a floating cutter bar is supported by a plurality
of laterally spaced linkages each of which are spring
biased by an upstanding compression spring at the rear of
the header. Another floating cutter bar construction is
shown in the UOS. patent 3,982,333 wherein a series of
quadrilateral linkages are employed to support a floating
cutter bar and a sheet spring is employed to partially
20 support it. U.S. patent 3,574$990 is of interest in that
it shows a harvester platform supported by parallel links
which are connected at their front and rear ends to the
platform and vehicle frame by ball and socket joints.
BRIEF DESCRIPTION OF THE INVENTION
This invention has particular use in a crop
harvester header of the type having a transverse rear
wall, a pair of standing end walls and a bottom structure
extending between the end walls and rearwardly to the rear
wall. The invention contemplates use of a flexible
floating cutter bar extending transversely along the front
of the header bottom structure and,a plurality of link
supported ground engaging skids secured in supporting
relation to the cutter bar at transversely spaced
intervals therealong. At least one pair of fore and aft
extending parallel links are provided for each of the link
supported skids. Means are provided to pivotally connect
the rear ends of the links to the bottom structure of the
header so that the linkages swing vertically about
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longitudinally spaced transverse axes and a pair of
universal pivot joints connect the front ends of the links
to the associated skids which,permit the skids to tilt to
accommodate flexing of the cutter bar along its length as
S the skids follow the ground contour during a harvesting
operation. Preferably the links of each pair of links are
in a one above the other relationship.
The invention may include provision of a lateral
stabilizer having a front end pivotally connected to one
of the skids by a ball and socket joint and the rear end
pivotally connected to the underside of the bottom
structure of the header on a transverse axis permitting
vertical swinging movement and preventing horizontal
swinging movement of the stabilizer and cutter bar.
Auxiliary skids may be provided which are not supported by
linkages from the header but rather are connected to the
cutter bar. Splice brackets may also be used to loosely
interconnect laterally adjacent ends of the skids. It may
also be desirable to provide stabilizer links at each
lateral end of the header which pivotally interconnect the
header and the cutter bar on axes spaced above the
transverse axes by which the links are connected to the
bottom structure and above the pivot joints by which the
links are connected to the cutter bar.
A concept of the invention includes the use of
first spring means in the form of a compression spring
interposed between a lever arm on one of the links of each
pair of parallel links and a second spring means in the
form of first and second series of sheet springs which are
in overlapping thrust transmitting engagement to provide
vertical support for the cutter bar. One series of sheet
springs are secured to and extend forwardly from the front
of the header bottom structure and the other series of
sheet springs are secured to the cutter bar and extend
rearwardly therefrom to overlap the front portions of the
first series of sheet springs.
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BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention is illustrated
in the drawings in which:
Fig. 1 is a side view of a header for a
combine;
Fig. 2 is a partial top view showing the
right-hand side of the header;
Fig. 3 is a partial top view showing the
left-hand side of the header;
Fig. 4 is a partial top view of the header
with portions broken away for illustration purposes;
Fig. 5 is a view taken along the line V-V
Fig. 4
Fig. 6 is a view taken along the line
VI-VI in Fig. 5, and
Fig. 7 is a view taker, along the line VII-VII
in Fig. 3.
DETAILED DESCRIPTION OF THE DRAWINGS
Referring to Figs. 1, 2 and 3, a combine header
11 includes a pair of vertical walls 12 and 13 at the
left and right-hand side of the header 11, an upright
rear wall 14 and a bottom structure 16~ A transversely
disposed cylindrical auger 17 is mounted by means not
shown on the side walls 12 and 13 for rotation about a
transverse pivot axls 18. Referring also to Fig. 4, the
bottom structure 16 includes a transverse hollow beam 21
to which a plurality of arms 22 and 23 are welded. The
bottom structure 16 also includes a curved, concave bottom
wall which extends downwardly and forwardly from the
transverse beam 21 as illustrated in Figs. 4 and 5. A
floating cutter bar assembly 36 is mounted on the header
11 and extends along the forward edge thereof between the
opposite side walls 12 and 13. The floating cutter bar
36 includes a cutter bar 37 which extends between the
opposite side walls 12 and 13 and to which a plurality of
guards 38 are attached The cutter bar 37 is bolted to
tabs 40 on a plurality of laterally spaced skids 41, 42,
43~ 44, 45, 46 and 47 by bolts 48 and nuts 49. The
skids are interconnected by splice brackets 51
interconnecting their adjacent ends. The fastening
means for connecting the splice brackets Sl to the skids
41, 42, 43, 44, 45, 46 and 47 as illustrated in Fig. 7
includes spools or spacers 54 through which bolts 56
extend. Retainer straps 57 have a hole through which
bolts 56 extend and the skids also include openings
through which the bolts 56 extend. The splicer bracket
51 includes openings 59 which are substantially greater
in size than the spools 54 thereby permitting
considerable movement between the splice brackets 51 and
the skids. These loose connections afforded by the splice
brackets 51 and fastening means allow relative movement
between the skids for traversing uneven ground. Skid
plates 41, 43 and 47 are mounted on the header 11 by two
pairs of parallel links or linkages 60 which will herein-
after be described. Skid 45 is mounted by a single paral-
lel linkage 60 and auxiliary skids 42 and 46 are secured
to the cutter bar 37 by a bolt 48 and nut 49 but are not
connected to the header 11 by a parallel linkage.
Referring to Figs. 4, 5 and 6, one parallel
linkage 60 for supporting the cutter bar 37 will be
described in detail. The forward ends of parallel links
61 and 62 are pivotally connected to a bracket 63
welded to the upper side of skid plate 64 of skid 45.
The bracket 63 includes a pair of upstanding flanges 66
and 67 with aligned openings for receiving bolts 68 and
69 which carry ball-like or spherically shaped bearings
71 and 72 disposed between suitable spacers through
which the bolts 68 and 69 also extend. The bolts 68 and
69 are secured by nuts 73 and 74. The forward ends of
the links 61 and 62 have spherically shaped sockets 76
and 77 in load bearing engagement with the spherical
surfaces of ball shaped members 71 and 72. These ball
and socket joints act as universal joints in providing
limited movement about a pair of longitudinally spaced
points 78 and 79. The rear ends of the links 61 and 62
are pivotally connected to a channel member 81 by
transversely extending pivot pins 82
and 83 which permit the links 61 and 62 to swing about
horizontal, transverse pivot axes 86 and 87 spaced from
one another in fore and aft direction. The spacing
between the axes 86 and 87 is the same spacing as provided
between the points 78 and 79. The rear ends of the links
61 and 62 include transverse bushiny portions 94 and 96
with radially inner cylindrical bearing surfaces
cooperatively engaging the outward facing cylindrical
bearing surfaces of pins 82 and 83 and serve to stabilize
the links against swing movement in a horizontal plane.
The lower link 62 includes a rearwardly extending lever
arm 98 the rear end of which is pivotally connected to an
eye bolt 99 by a transverse pivot pin 101. The eye bolt
99 carries a nut 102 and a washer 103 and extends
rearwardly through a coil compression spring 104 and
through an opening in an abutment plate 106 welded to the
channel member 81. The rear end 107 of the eye bolt 99
extends through an enlarged opening in the abutment plate
106 so that it is free to move relative thereto as the
floating cutter bar raises and lowers. The compression
spring 104 is preloaded by adjusting nut 102 to exert a
- clockwise torque on the arm 62, as viewed in Fig. 5, to
partly counterbalance the weight of the floating cutter
bar assembly 36. As shown in Fig. S, the spring 104 is
least effective in exerting a moment on lever 62 because
the effective lever arm is short; however, as the 10ating
cutter bar assembly 36 swings upwardly the effective lever
arm increases and the spring 104 experts a greater counter
balancing torque or moment A primary spring biased
support for the floating cutter bar assembly 36 is
provided by cooperating sheet springs 111 and 112. The
front of the front sheet spring 112 is secured Jo the
cutter bar 37 by a series of bolts 113 and nuts 1140 The
rear sheet spring 111 is secured at its rear to the header
bottom wall 31 by bolts 116 and nuts 117~ The front
sheet spring 112 has a rear end portion in overlapping
relation to a front end portion of rear sheet spring 111
and these springs are so proportioned so that there will
always be an overlap regardless of the position of the
cutter bar 37 in relation to the header 11. The sheet
springs 111 and 112 also serve as a ramp for moving crop
material cut by the reciprocating sickle 121 during a crop
harvesting operation. The rear and front sheet springs
111 and 112 are provided in segments which extend
laterally roughly between the parallel supporting linkages
60. Their adjacent lateral ends are in lapped relation to
one another so that seed or grain will not be lost and to
accommodate a transverse wave-like form that may be
assumed by the floating cutter bar as it traverses uneven
terrain. The sheet springs provide greater lift to the
floating cutter bar assembly in the latter 1 5 lowered
position, as shown in Fig. 5, than in the raised position
thereof shown in Fig. l Thus, when the primary springs
111 and 112 exert the least lift, the secondary springs
104 are providing their greatest lift an vice versa.
Referring to Figs. 1, 2 and 3, the sickle 121 is
driven by a wobble drive 131 whose output member or lever
132 is connected to the end of the sickle 121 by an
upstanding pivot bolt 133. The wobble drive housing 137
is bolted to brackets 161, 162 which in turn are bolted to
skid 47. A bracket 136 rigidly secured to the top of the
wobble drive housing 137 is interconnected to the side
wall 12 by a link 138 whose front end is pivotally
connected to the bracket 136 by a transverse pivot pin 139
and whose rear end is pivotally connected to the side wall
12 by a transverse pivot pin 141. The link 138 serves as
a stabilizer link and prevents the parallel linkage from
locking up when the floating cutter bar 37 is in its
extreme raised position. A5 shown in Fig 2~ a similar
stabilizer link 143 is provided on the right side of the
header 11 with its rear end connected to the header end
wall 13 on a transverse axis 144 and with its front end
pivotally connected on a transverse axis 147 to an
upstanding bracket 146 secured to the skid 41. The cutter
bar assembly 36 is stabilized ayainst lateral shifting
movement relative to the header 11 by a lateral s~abili2er
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151 whose front end is pivotally connected to an
upstanding bracket 152 on the skid 47 by a ball and socket
joint 153. The rear end of the lateral stabilizer 151 is
pivotally connected on a transverse axis 154 by pivot pin
156 connected to brackets 157 and 158 secured to laterally
spaced channel members Bl.
Although not fully illustrated in Figs. 2 and 3,
it should be understood that a parallel linkage 60 is
interconnected between each aligned set of channel members
31 and skid brackets 63.
OPERATION
It is particularly important for the cutter bar
to closely follow the ground contour when harvesting low
podding plants such as soybeans. The mounting arrangement
for the cutter bar 37 permits it to assume an end-to-end
configuration similar to the contour of the field being
harvested. The parallel linkages permit different lateral
points of the cutter bar 37 be at different vertical
positions and the use of a series of lateral spaced skids
insures flexing of the cutter bar 37 along its length as
the skids move up and down (and tilt) in following the
field contour. The ball and socket joints securing the
parallel linkage to the cutter bar skids permit the skids
to change their angular relationship to each other.
In harvesting with a floating cutter bar, it is
desirable to have a light cutter bar in wet conditions to
keep the cutter bar from digging into the ground and a
relatively heavy cutte bar in dry field conditions to
provide a low cutting height and rush the plant stubble.
30 The primary springs (sheet sprints 111 and 112) and the
secondary springs 104 in combination provide adequate
counterbalancing forces throughout the vertical floating
range of the cutter bar. The secondary spring force can
be adjusted by turning nut 102 to change the counter-
balance and hence change the down pressure exerted by the
floating cutter bar assembly 36 on the ground. The use of
front and rear overlapping sheet springs provides a better
loading ramp contour for the harvester crop than prior
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single sheet springs spanning the fore and aft space
between the cutter bar and the header bottom. The flatter
profile provided by the double sheet spring arrangement of
this invention reduces the likelihood of seeds being lost
over the front of the cutter bar.
