Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to a land levelling device
for use with a tractor or other farm implement. More parti-
cularly this invention relates to a device especially adapted
to level a narrow strip of land immediately in front of a
tractor wheel.
There are, of course, many types of land levelling
devices on the market or which have been developed for
specific applications, including harrows, rollers and the like
which are towed behind a powered vehicle such as a tractor,
and blade devices which are normally mounted on the front of
a powered vehicle. With any leve~ling device which is
mounted behind the tractor there remains the problem that
the ground over which the tractor is travelling has not yet
been levelled and this can result in an extremely uncomfort-
able ride for the driver as well as imposing severe strains
on the vehicle suspension. The problem is particularly severe
when a tractor is being used to cross cultivate ploughed or
even ploughed and harrowed land. The transverse ridges left
by the plough create a washboard effect which is extremely
fatiguing for the driver as he is constantly bracing himself
against the next bump. A blade attachment, such as a bull-
dozer blade across the front of the tractor would, of course
solve the problem of a rough ride, but such blades are
expensive to produce and operate. Indeed it is rarely
possible to attach a bulldozer blade to the front of a
; powered vehicle and use it to clear a smooth path for the
vehicle and still have enough power available to be able to
tow a cultivating implement or the like behind the vehicle
as well. It is clear therefore that a bulldozer blade
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actually moves far more earth and the like than is actually
required to provide a smooth ride for the tractor driver.
It is an object, therefore, of the present invention
to provide a simple, relatively inexpensive attachment for
mounting on the front of a tractor or the like which will
smooth a pair of parellel, spaced narrow paths, each just
sufficiently wide to permit passage of a tractor wheel, thus
ensuring a relatively smooth ride for the driver.
Thus, by one aspect of this invention there is
provided a land levelling device for attachment to a tractor
forwardly thereof, comprising:
frame means having a pair of forwardly projecting parallel-
ly spaced arms;
means to attach said frame to said tractor;
at least two arms pivotally supported from said frame
and dependent downwardly therefrom;
ground levelling blade means rigidly mounted at the lower
end of each said dependent arm; and
means to pivot said blade means into and out of ground
contact.
The invention will be described in more detail herein-
after with reference to the drawings in which:
Figure 1 is an isometric view of one embodiment of
the present invention, attached to a tractor;
Figure 2 is a side view of the device of Figure l;
Fiqure 3 is a plan view of the device of Figure 1: and
Figure 4 is an isometric view of an alternative embodi-
ment of the invention, attached to a tractor.
In Figure 1 there is shown a device of the present
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invention attached to the front of a tractor 1 (shown in
phantom). A frame 2, having a cross bar 3, a pair of
parallel forwardly extending arms 4 and 5, and a pair of
parallel rearwardly extending arms 6 and 7, is pivotally
mounted on the front axle 8 of the tractor 1 at the outer ends
of arms 6 and 7, via mounting brackets 9, on each side of the
tractor motor, and pivot pins 10. Pivotal movement of
frame 2 between a lowered operative position and a raised
inoperative or travelling position is effected in any conven-
tional manner as by means of one or more hydraulic cylinders 11and 12 pivotallymounted at one end thereof to brackets 13 and
14 on one or both sides of the tractor frame, and to suitable
lugs 15, 16 on frame 2 at the other end thereof.
Downwardly dependent arms 17 and 18 are pivotally
mounted at the forward ends of arms 5 and 6 respectively and
provided with springs 19 and 20 biasing the ground engaging
ends of arms 17 and 18 forwardly. V-shaped harrow-type blades
21 and 22 are secured to the ground engaging ends of arms 17
and 18. In the event that blades 21 or 22 strike a rigid
obstruction arms 17 and 18 are moved rearwardly against the
action of springs 19 and 20. Preferably, but not essentially,
a slotted plate 23 is slidably secured between dependent
arm 17 and arm S, and similarly between arm 18 and arm 4,
to act as a stabilizer against twisting of the respective
dependent arms relative to the frame.
It will, of course, be appreciated that the design of
blades 21 and 22 is a matter of choice and that these blades
may be of any selected length, depending upon the vehicle to
, which they are attached. As seen most clearly in Figure 3
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the length of the arms of blades 21 and 22, and the angle
between them should be selected such that the width of the
swept path created thereby is slightly greater than the
width of the tractor tire 24 behind it. In the event that a
tractor with dual rear wheels is employed, it may be preferable
rather increasing the length of blades 21 and 22 to cover both
wheels, to provide dual blades on each side of the tractor.
As the levelling path is relatively narrow, relatively little
of the power available from the tractor is actually used to
smooth the path, and consequently regular cultivating operations
with a towed implement can be carried out without difficulty
with the same sized tractor.
An alternative and preferred embodiment of the
invention is illustrated in Figure 4. Frame members 30, 31 are
securely bolted to front axle 8 on each side of the tractor
motor and projecting substantially horizontally forwardly in a
planar relationship. Adjacent the outboard ends thereof
there is provided a substantially circular hole 32, 33 through
which a bar 34 is inserted for angular rotation. Arms 17 and
18 are rigidly mounted on bar 34 and depend downwardly. Blades
21 and 22 are rigidly mounted at the lower ends of arms 17, 18
for ground engagement as described above. In order to position
blades 21 and 22 in either a ground engaging position or a
pivotally retracted position, a lever arm 35 is rigidly secured
to bar 34 at a position intermediate holes 32 and 33 and
pivotally connected to a hydraulic cylinder 11, mounted on one
side of the tractor frame. Generally a single cylinder 11 is
sufficient although it will be appreciated that a second
cylinder 12 may be provided on the other side of the tractor
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frame if required. Hydraulic cylinder 11 is actuable, utilizing
power from the tractor, to move the upper end of lever arm 35
back and forth, thus pivotally turning bar 34 and blades 21 and
22 into and out of ground engagement respectively. Cylinder 11
also provides some resiliency, in the form of an accumulator,
should the blades 21, 22 strike a rock or the like.
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