Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to tillage implements partic-
ularly those used for minimum tillage farming.
In minimum tillage farming the object is to disturb
the soil as little as possible and perform weed eradication
and other operations in which soil disturbance can occur,
with chemical treatment. Usually planting under minimum till-
age conditions involves in one operation only breaking the
soil, depositing the seed~ depositing fertilized or other
nutrients and/or pest control substances and closing the
furrow over the seed-
In such operations it is usual to form a narrow cutin the soil to form a thin trench into which the seed is
deposited. A difficulty with this technique is that the move-
ment of the tillage implement through the soil produces a
smear or glazed effect on the soil face of the side walls and
bottom of the trench. This effectively provides a barrier to
root penetration in the early life of the plant. After
germination the roots of the plant travel outwardly from the
seed but meet the barrier of the walls and bottom of the
origi~al seed trench ~now filled in~. Following the path of
least resistance the roots tend to move upwards with the
plant stem. Consequently in this stage of growth the plant
experiences difficulty with obtaining soil nutrients and its
growth is retarded if not eventually terminated.
There have been attempts to solve these diff-
iculties and examples are provided in U.S. Patent 3~667,550
(Lehman) and U.S. Patent 4,333,536 (Ryan). Both of these
patents disclose shares which provided an undercut to the
sides of the trench formed by the share. Ryan is concerned
with minimum tillage and provides a narrow soil opening.
However, in Ryan's arrangement a larger portion of the
implement and its associated tine is required below the soil
surface. Further soil displacement with the Ryan device is
not always satisfactory in that during seed planting delivery
of seed does not always precede the fall of soil back into
the trench.
It is an object of this invention to overcome these
~n~ o .L ~
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difficulties experienced in the conventional mode of practis-
ing minlmum til:lage.
To this end the present invention provides a till-
age implement comprising a shaft portion adapted to be
secured to a tine and an earth engaging portion located below
said shaft portion and comprising a soil contacting portion
located forward of said shaft and two parallel side portions
extending rearwarclly and terminating behind the shaft portion
and an externally projecting lateral flange located adjacent
the lower edge of said earth engaging portion.
The flange preferably extends horizontally to
provide an incision in the side walls of the soil trench and
cause soil fracture at the outer edge of said incision. Con-
sequently at least one side of the seed trench provides a
lateral path for sideways root growth. Furthermore, there is
no glaze or smear at the outer edge of the incision and root
growth beyond that point is not impeded. In this way the
present invention provides a means of avoiding the difficulty
of early retardation of plant growth in minimum tillage opera-
tions.
It is preferred that when the tillage implement ofthis invention is mounted on a tine that the implement is
inclined forwardly at an angle of 5 to 20-preferably 10 to
the horiæontal. This angled penetration of the soil results
in the lateral flanges lifting the soil slightly and forming
horizontal cracks which ex~end laterally from the base of the
trench and consequently provide a penetration path for the
plants root system. In addition the inclination of the
implement allows a proportion of the displaced soil to fall
into the trench undernea~h the edge oE the rear of said side
portions. The soil which wou]d fall into the trench in this
way is the moister lower soil layer. When the seed is
initially covered by this moister layer, germination is
enhanced. The bulk oE the soil will fall into the trench
af-ter passage of the side portions.
Preferably the shaft and earth engaging portion are
integra] ancl are formed by folding a metal blank to form an
angled narrow leading face with two parallel vertical sides
extending ~earwardly from the lower portion of said leading
face and the upper portion being formed into a hollow recess
shaped to receive a tine. Conveniently the lower edge of the
leading face and a portion of the lower edge of the side por-
tions are turned outwardly to form said lateral flange.
The width of the tillage implement of this inven-
tion should be narrow to form only a narrow opening in the
soil. The minimum width is determined by the thickness of
the tine and the metal of the implement itself which is
folded about said tine. A seed dropping tube is preferably
located behind the tine and drops seed into the space between
the two side portions at a location behind the shaft. These
two parallel side portions do not displace soil but act to
provide a space for the seed to fall to the bottom of the
trench. Once the implement has moved on the soil falls back
into the trench covering the seed. It is the substantially
vertical sides of the two parallel side portions which make
it possible to obtain neat return of the soil into the trench
with good seed coverage. As mentioned above, some moister
soil will fall into the trench under the edges of the side
portions if the implement is inclined to the horizontal. It
is preferred to increase this beneficial effect further by
removing a triangular section from the lower edge of the rear
section of said side portions.
A preferred embodiment of this invention is
illustrated in the accompanying drawings in which Figure 1 is
a front elevation, Figure 2 is a side view of the implement
attached to a tine, Figure 3 is a ~ront perspective view,
Figure 4 is a near perspective view, Figure 5 is a plan view,
and Figure 6 is a perspective view of the implement secured
to a tine.
The ~illage implement illustrated comprises a shaft
10, a leading point 11, a body portion 12 and trailing pane:Ls
13. The shaft is hollow and tapered internally to fit in
frictional engagement on the foot of a complementary tine 18
of an agricultural machine as shown in Figure 6. The point
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11 and body secti.on 12 in moving through the soil form a seed
trench. Extending outwardly from the point 11 and body por-
ti.on 12 is a f].ange 15 which acts to cut two lateral inci-
sions in the boltom of the side walls of the seed trench and
so provide a growth path for the plant's roots subsequent to
germination. As shown in Figure 2, it is preferred to have
the implement when mounted on a tine to be inclined about 10
to the horizontal.
The panels 13 provide a channel 16 behind the body
section 12 into which a seed tube 19 can extend to drop seeds
at predetermined intervals. The seed tube 19 is attached to
the rear of the tine 180
After passage through the soil of the trailing
panels 13 the displaced soil of the trench falls back into it
lS to cover the seed and close the trench. As shown in Figure
2, the lower edge of the rear part of the traillng panels 13
can be inclined upwardly to increase the flow of soil into
the seed trench from below said panels 13.
From the above it can be seen that the present
invention provides a unique means of ensuring steady plant
growth after seed planting using minimum tillage methods.
