Note: Descriptions are shown in the official language in which they were submitted.
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CA PATENT
FILE NO. 45113-04
SHANK MOUNTING ADAPTER FOR GROUND-OPENING TOOLS
Field of the Invention
The present invention relates to agricultural implements, and relates in
particular to an
adapter for mounting ground-opening tools on cultivator shanks.
Background of the Invention
Crop farming requires the soil to be opened by plowing in order that seeds may
be planted
at a desired depth below the soil surface. This plowing operation is commonly
carried out using a
cultivator, which is an implement having a number of downward-oriented shanks
to which ground-
opening tools may be mounted. Ground-opening tools, commonly referred to as
"sweeps", are
typically vee-shaped or wedge-shaped, and have an upstanding stem for mounting
to the shanks of
the cultivator. As the cultivator is drawn forward, such as by a tractor, the
shanks may be lowered
so that the sweeps penetrate the soil to a desired depth, forming a furrow in
which seeds may be
deposited. Typically, the seeds are deposited through seed boots mounted to
the cultivator shanks
inunediately behind the sweeps.
Despite being made of metal, sweeps become abraded and worn as they are pulled
through
the soil, and they may also become damaged by objects in the soil such as
rocks. For such reasons,
sweeps need to be replaced regularly. However, removal and replacement of
sweeps is often a
difficult and time-consuming operation. Shanks are typically made from square
or rectangular bar
stock, with a pair of holes passing from front to back through the shanks near
their lower ends.
Sweeps are commonly mounted to such shanks with bolts running through the
holes in the stem of
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the sweep and the shanks, with one end of each bolt exposed in front of the
stem and the other end
exposed on the back face of the shank. The bolts are thus exposed to abrasive
action and moisture
in the soil. The abrasive action of the soil as the shank is drawn forward may
lead to premature
wear. As a consequence of exposure to moisture, the bolts often rust such that
the threads of the
bolts become "frozen", making it virtually impossible to remove the bolts in
the usual fashion. In
such cases the only alternative may be to cut the bolts off with a hacksaw or
even an acetylene
torch. This is very inconvenient because it will often be desired to replace
one or more sweeps
while the cultivator is operating out in the field, perhaps miles from a
convenient workshop,
perhaps in inclement weather conditions, and perhaps late in the day when
lighting conditions are
poor.
The prior art discloses numerous attempts to address some of these problems.
The
apparatus described in U.S. Patent No. 4,195,697, issued to Griffin on April
1, 1980 (corresponding
to Canadian Patent No. 1,093,889 issued to Griffin on January 20, 1981),
features a two-piece
bracket which bolts onto a typical shank using the standard holes in the
shank, with the shank being
sandwiched between the two pieces of the bracket. The portion of the bracket
mounted on the rear
face of the shank has one or more transverse holes for fastening a sweep with
one or more bolts.
The Griffin apparatus uses a sweep having a stem with flanges that extend
rearward of the shank
and which have holes corresponding to the transverse holes in the rear
component of the bracket.
The sweep covers up the heads of the bolts that attach the two-piece bracket
to the shank. No
means for adapting the two piece bracket to shanks with different hole spacing
is disclosed.
In US Patent No. 4,867,248, issued to Robertson et al. on September 19, 1989 a
shank
mounting assembly for a soil opening point also provided an adapter between
the point and the
shank. In this case, the elongated adapter comprises an upper shank mounting
portion and a lower
point-mounting portion. The lower portion included a forwardly extending
tongue that is received
by a rearwardly open socket of the point. A transversely extending pin then
secures the tongue and
point. The upper portion of the adapter is provided with a hidden bolt-
retaining cavity at the
backside for mounting on the shank. Thus, no boltholes are presented on the
front face of the
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assembly by which soil can gain access to bolt heads. To provide for a slight
variation in the angle
of attack of the point, a shim may be located between the upper portion of the
adapter and the
shank.
While the above-mentioned patents represent improvements in the art of bolt-
mounted
cultivator sweep constructions, a disadvantage is that they require the
manufacture and assembly of
multiple parts. In addition, they do not provide for height adjustments of the
sweeps that would
allow for greater control of tillage conditions. There is a need in the art,
therefore, for a simply
constructed, easily releasable bolt-mounted cultivator sweep assembly wherein
the height and the
angle of attack of the sweep may be independently adjusted.
Summary of the Invention.
The invention provides an agricultural cultivator apparatus wherein a ground-
opening tool
may be removably mounted onto a standard tool supporting shank by means of an
adapter. In one
embodiment, the adapter is of unitary construction and generally comprises a
mounting face,
configured to mate with the front surface of the tool holding portion of a
shank, a bulinosed prow
section and a trailing section. The tool is secured onto the prow section by
means of a bolt that
projects transversely through the prow and the tool. The adapter is so
designed as to receive two
longitudinally spaced-apart shank bolts that project from front to back
through the lower tool-
holding portion of the shank for securing the adapter on the shank. In the
adapter, a recess open to
one side of the prow section fits the lower shank bolt and a slot in the
trailing section extending
from the top through the bottom of the adapter fits the upper shank bolt.
In one embodiment, the prow section may also provide at least two vertically
spaced apart
transverse holes such that the ground-opening tool may be bolted onto the
adapter using any one
hole. In this manner, the height of the tool may be adjusted relative to a
fixed mounting location of
the adapter on the shank. The lower shank bolt receiving recess and the upper
shank bolt receiving
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slot of the adapter may be elongated along the length of the adapter. In this
manner, the mounting
location of the adapter on the shank may be adjusted upwards or downwards,
within the limits of
the recess and slot. When mounted on a shank having a vertical curvilinear
configuration, this may
also provide for adjustment of the angle of attack of the ground-opening tool.
Therefore, in one embodiment , the invention comprises an adapter for
releasably mounting
a ground opening tool to a cultivator shank having a tool holding portion
defining an upper and a
lower bolt hole, said adapter comprising:
(a) a mounting face, generally configured to mate with the tool-holding
portion of the
shank;
(b) a prow section configured to mate with a mounting stem channel of a ground
opening tool and defining at least one hole through which a mounting stem bolt
may
be secured, the prow section also having a recess for receiving a lower shank
bolt,
the recess being open to one side of the prow section as well as through the
mounting face and configured to receive the bolt with the head of the bolt
retained
within the recess and with the shaft of the bolt projecting through the
mounting face;
and
(c) a trailing section defining an opening for receiving an upper shank bolt
which
passes through the mounting face with the shaft of the bolt projecting through
the
opening.
In one embodiment, the mounting stem and the leading edge of the prow section
are substantially
vertical when mounted to the shank. The prow section may comprise a plurality
of spaced apart
holes that provide alternative locations for retaining the mounting stem bolt.
The upper shank
bolt receiving slot may be elongated. Alternatively, both the recess and the
upper shank bolt-
receiving slot may be elongated along the length of the adapter, thereby
providing for a range of
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mounting locations of the adapter on the shank, within the limits of the
recess and the slot.
Brief Description of the Drawings
Embodiments of the invention will now be described with reference to the
accompanying drawings, in which numerical references denote like parts, and in
which:
FIGURE 1 is a perspective view of embodiment of an adapter of the present
invention in relation to a sweep and a shank.
FIGURE 2 is a front view of the adapter shown in Figure 1.
FIGURE 3 is a side view of the adapter shown in Figures 1 and 2.
Detailed Description of an Embodiment
Referring to the Figures, an embodiment of the present invention comprises an
adapter (10)
of unitary construction for mounting a ground opening tool (12) such as a
sweep to a cultivator
shank (14).
As shown in Figure 1, the adapter (10) comprises a forward prow section (20)
which mates
with a mounting stem (16) of the sweep (12). The mounting stem (16) is U-
shaped in cross-section
so as to mate with the prow section (20). Mounting holes (22) in the prow
section (20) allow the
sweep (12) to be bolted to the adapter through a sweep bolt hole (24). In one
embodiment, at least
two mounting holes (22) which are vertically spaced apart are provided thereby
allowing a user to
adjust the vertical position of the sweep (12).
The adapter (10) further comprises a trailing section (26) which defines an
opening which is
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used to bolt the trailing section (26) to a shank. In one embodiment, the
opening is a groove (28)
and slot (28) which pass clear through the trailing section (26) and a
mounting face (30). The
mounting face (30) mates with the cultivator shank (14) and the groove (28)
extends into a slot (32)
which opens through the mounting face (30). Preferably, the groove is sized
such that when a
mounting bolt is placed in the groove (28) and passes through the slot (32),
the head of the bolt
engages the groove (28) such that it cannot rotate. As a result, a nut (40)
may be tightened or
loosened without the need to grasp the head of the bolt with a wrench or the
like. The head of the
bolt will bear on a shoulder (31) so as to secure the adapter to the shank.
The prow section (20) may also define an opening which is used to bolt the
prow section to
the shank. In one embodiment, this opening is a recess (34) which may receive
a mounting bolt.
The recess (34) is open to one side of the prow section (20) and through the
mounting face (30) as
is shown in Figure 3. The recess (34) defines a shoulder (35) which the head
of the mounting bolt
will bear upon when tightened. Preferably, the recess is shaped to closely
receive the mounting bolt
head such that the bolt cannot rotate when the bolt is placed in the recess
(34).
The adapter (10) may be mounted to the cultivator shank by aligning the slot
(32) with an
upper bolt hole (36) in the shank and the recess (34) with a lower bolt hole
(38) in the shank. In
one embodiment, the slot (32) is elongated, thereby allowing the adapter (10)
to be mounted to a
wide variety of shanks with different bolt hole spacings.
In one embodiment, both the slot (32) and the recess (34) are elongated
thereby allowing for
some adjustability of the position of the adapter (10) on the shank. As a
result, sweep height and
angle of attack may be adjustable. For example, if the adapter is mounted
lower on the shank, the
2 5 tip of the sweep may be adjusted upward slightly. If the adapter is
mounted slightly higher on the
shank, the tip of the sweep may be adjusted slightly downward.
In the embodiment illustrated, the recess (34) and the lower sweep mounting
hole (22) are
shown to overlap. However, it is not intended that the position of the sweep
mounting holes (22)
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relative to the recess (34) be limiting of the claimed invention.
Preferably but not essentially, the adapter (10) is of unitary construction
and may
conveniently be cast with a suitable metal.
It will be readily seen by those skilled in the art that various modifications
of the present
invention may be devised without departing from the essential concept of the
invention, and all
such modifications and adaptations are expressly intended to be included in
the scope of the claims
appended hereto.
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