Note: Descriptions are shown in the official language in which they were submitted.
MOWER ~SSEMBLY
. . _
BACKGROUND OF T~E INVENTION
1. Fleld of the Invention.
The present invention pertains to a mower
05 assembly and particularly one employing an improved
sickle guard to provide greater cutting action.
The standard sickle guard provides for a
spacing between the sickle guard fingers which is
e~ual to the spacing between the teeth of the sickle
bar. Customarily, this is a 3-inch spacing. There
is also a standard 3-inch stroke so that each tooth
alternately moves betwen two sickle guard fingers.
The movement of the single tooth against the sickle
guard finger creates a shearing action. The sickle
guard finger functions both to provide for the
shearing action and also to support and protect the
sickle blade as it moves back and forth.
The problem with the standard sickle guard
is that a standard stroke equal to the spacing
between the fingers slows down the machine and
results in considerable shattering of the plants,
resulting in substantial shatter loss. In other
words, there is so much movement o~ the blades that
the plants are hit sidewise, without cutting them, as
the blade moves from one sickle guard finger to the
next sickle guard finger.
2. Descr ption of Prior Art
There have been various attempts to solve
this problem. One of them involves placing twice as
many sickle guard fingers on the sickle guard
support. A typical sickle guard finger has a
rearwardly facing slot through which the sickle bar
moves. The problem with this is that the tight fit
due to increased number of sickle guard fingers tends
339
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to result in binding problems in wet conditions.
Furthermore, these extra fingers create more pushing
problems in certain crops and large weeds. The
additional finger sections are also very prone to
05 breakage.
The Ronning V.S. Patent 2,226,583 employs
two fingers for each sickle guard section. One of
these is a full sickle guard finger with a rearwardly
facing slot, and the other one is a short finger
which does engage the cutter blade in cutting
engagement, but which does not support it by the use
of a rearwardly facing slot, as is the case with the
long fingers. While the arrangement of Ronning
increases the number of cuts per stroke of the sickle
and decreases the pushing problems that arise when
twice as many long fingers are employed, the Ronning
arrangement has certain drawbacks. In the first
place, it is mounted on a vertically disposed
flange. This is not a very satisfactory design for
low height cutting as is required for a crop like
soybeans. Furthermore, the individual teeth e~tend
directly from the cross support bars and do not have
any reinforcement. In additon, each tooth section is
fastened by merely one fastener. This can result in
the guard sections tilting slightly, causing
alignment problems.
The Curtis U.S. Patent 209,465 shows an
arrangement in which there are a plurality of
sections, each o~ which contains one long guard
finger and one short one. It does use vertical
bolts, unlike Ronning. On the other hand, there is
only one bolt per section so that there would be a
tendency for the sections to tip sidewise~
Furthermore, in order to get four fingers, it is
~LX~7~339
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necessary to use two sections. There is no
reinforcement for the guards and there would be a
tendency for trash to collect between the various
guard fingers.
05 The U.S. Patent to ~elley 1,581,214 shows an
arrangement employing long and short fingers. There
apparently is no contact with the knife with the
short fingers. Also, there is only one long finyer
and one short finger for each guard section.
SUMMARY OF THE INVENTIO~
The present invention is concerned with a
mower assembly in which there is a sickle bar having
a pluraity of uniformly spaced teeth mounted for
horizontal reciprocation and means for guiding the
sickle bar during its reciprocation, this ~eans
including a plurality of guard sections, each
including at least four guard fingers in cutting
engagement with the sickle bar. The alternate guard
fingers are relatively long and include rearwardly
facing slots through which the sickle bar moves. The
other guard fingers are relatively short and extend
forwardly substantially the same distance as the tip
of the teeth of the sickle bar. Each guard section
is fastened at spaced points to the guard support bar
so as to minimize any tendency of the guard section
to turn with respect to the support bar.
The mower assembly preferably has trash
guard bars extending parallel to the support bar
between the guard fingers. These trash guard bars
are rigidly secured to the adjacent guard fingers at
an area adjacent the base of the teeth of the sickle
bar. These trash guards reinforce the guard fingers
and minimize the tendency of trash to collect between
the teeth.
3g
The support bar is parallel to the plane of
the sickle bar and the guard sections are secured to
the top of the support bar. The fastening means for
securing the guard sections to the support bar are
05 preferably each disposed on a center line extending
longitudinally through an adjacent guard finger.
Other features and objects of the invention
will be apparent from a consideration of the
accompanying specification, claims and drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a top plan view of the mower
assembly of the present invention;
Figure 2 is a bottom plan view of the mower
assembly;
Figure 3 is a sectional view taken along the
line 3-3 of Figure 1, and
Figure 4 is a sectional view taken along the
line 4-4 of Figure 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, the reference
numeral 10 is used to generally indicate a sickle~
bar. This sickle bar, which will be described in
more detail later, cooperates with a plurality of
guard sections 11 which are secured to a guard
support bar 12 running longitudinally of the sickle
bar.
Referring to the sickle bar 10, this is a
conventional type of sickle bar comprising a
plurality of knife sections 15 secured to the upper
surface of a bar 16 by rivets 17 or other suitable
fastening means. Each knife section 15 is generally
identical and is formed of a relatively thin member
having forwardly converging sides. The opposite
faces of each knife section are beveled to form
cutting edges 19. The sickle bar 10 is supported to
a large extent by the guard sections 11, as will be
presently described, and is actuated by conventional
actuating means (not shown) so as to reciprocate back
05 and forth.
Referring to the guard sections 11, each of
these comprises two long fingers 22 and 23 and two
short fingers 2~ and 25. All of the four fingers are
secured to a crossbar 28, as best shown in Figure 2,
preferably being integral therewith. Crossbar 28 is
provided with two spaced ears 30. These are secured
to the guard support bar 12 by cap screws 31, as best
shown in Figure 3. The cap screws extend through the
guard support bar 12 into the ear portions 30 of the
crossbar 28. By having two separate fasteners 31 for
each guard section, the guard section is held firmly
against any tendency to turn, as is the case where
each guard section is fastened to the support guard
by only one fastening means.
Extending between the fingers are trash bars
32. Each trash bar is rigidly secured to the
adjacent guard fingers, as best shown in Figure 2.
Normally, these trash bar sections are integral with
the adjacent guard fingers. The trash bar~ 32 serve
to reinforce the fingers 22, 23, 24 and 25.
Furthermore, they prevent trash from jamming between
the various guard fingers, as would be the case if
they were not present. It will be noted that the
trash bars are adjacent of the base of the inclined
cutting edges 19 of the sickle bar sections 15.
Referring now to the manner in which the
cutting action worXs, the long guard fingers 23 are
each provided with a slot 33, as best shown in Figure
3. The knife sections 15 of the sickle blade move
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bacX and forth through this slot. The finger 23 is
provided at the base of the slot 33 with a cutting
sur~ace 34 with which the cutting edges 19 of the
sickle blade sections 15 cooperate. As the blade 15
0S moves back and forth, the cutting edges 19 cooperate
with the cutting surface 14 to provide a shearing
action.
Referring now to the short fingers 2~ and 25,
the finger does not have a slot through which the
sickle blade 15 moves. On the other hand, it does
have a shearing or cutting surface 35 which
cooperates with the cutting edges 19 of the blade to
produce a shearing action. Thus, shearing takes
place both in connection with the long fingers 22 and
23 and the short fingers 24 and 25.
As is best seen in Figures 2 and 4, the tips
of the knife sections 15 extend forwardly beyond the
forward ends o~ the short fingers 24 and 25. This
has the advantage that any plant approaching a short
finger is moved sidewise into cutting engagement with
the blade either as it moves along the short finger
or moves along an adjacent long finger. This
minimizes any tendency of the plants to jam up
between the Xingers, as happens when the blade does
not extend beyond the forward end of the short
fingers.
The long fingers 22 and 23 are provided with
grooves 37 and the short ingers 24 and 25 are
provided with similar grooves 38. The grooves 37 and
38 collectively provide a channel through which the
sickle bar 16 and the rivets 17 can move without
obstruction.
~71~3~3
OPERATION
Referring now to the operation of the entire
mowing assembly, and referring specifically to Figure
2, the sickle bar 10 moves back and forth the
05 distance between the long finger 22 and the long
finger 23. The blades 15 are shown in the drawin~ in
the center portion of their stroke. Thus, for each
stroke in one direction, the sickle blade 15 moves in
shearing engagement with the shearing surface 34 of
the long finger 23, into shearing engagement with the
short finger 24 and then into shearing engagement
with the other long finger 22. Thus, for each stroke
of the sickle bar, the sickle blade comes into
contact with the shearing surfaces of three guard
fingers. This produces twice as much shearing effect
as is normally the case with the conventional mower
assembly.
Because of half of the fingers being short
fingers, there is much less resistance to the
movement of the mower bar through the material being
mowed. Where all of the fingers are long fingers,
there is considerable resistance to movement of the
sickle bar. Furthermore, because of the alternate
fingers being short, any tendency for rocks to jam
between the fingers is minimized.
The trash bars 32 serve several functions.
In the first place, they greatly minimize the
tendency of rocks or plants to become jammed between
the fingers. Since the trash bars are adjacent the
junction of the cutting edges of the sickle blades,
they do not appreciably affect the cutting action.
Moreover, they greatly reinforce the fingers 22
through 25 in that they form a rigid connection
between the fingers well forward of the crossbar 2~.
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It is to be pointed out that the guard
~ections 11 customarily have the same spacing of the
ears 30 as with the conventional type of guard
section in which there are two long fingers for each
05 guard section. All that it is necessary to do to
convert to the present device is to remove the
standard guard sections and secure the new guard
sections, thus doubling the cutting ac-tion and
minimizing the shatter loss due to the long distance
that the cutting blade must travel between the guard
fingers. With ~he present arrangement, the tendency
to shatter is greatly reduced.
While I have shown an arrangement in which
any one blade cooperates with three guard fingers, it
is to be understood that, if desired, there can be
twice as many blades so that there is one blade for
each guard finger, the length of the stroke being the
same. This gives the advantage of twice as much
c~ltting action.
While I have shown certain specific
embodiments for purposes of illustration, it is to be
understood that the scope of the invention is limited
solely by that of the appended claims.
