Note: Descriptions are shown in the official language in which they were submitted.
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RAKE ATTACHMENT FOR A SKID STEER
This invention relates to a rake attachment with scarifying teeth for a skid
steer
loader.
The present divisional application is divided out of parent application Serial
No. 2,129,494 filed on April 8, 1994.
The invention of the parent application relates to a tool characterized by
having a
support frame that allows visual access by the operator to the tines.
The invention of the present divisional application relates to a tool
characterized
by having a rake blade and a set of spaced scarifying teeth.
Grounds preparation for seeding and lawn installation is a part of most
building
and construction projects. Preparing soil for seeding and lawn installation
involves
grading, filling, leveling and scarifying the soil around buildings, side
walks, trees and
other obstacles. Conventional industrial and commercial earth moving equipment
is
designed to operate in large open areas, thus they are not well suited for
operation in
confined areas or around the edges of buildings and other structures.
Consequently, most
of the finishing work around buildings and confined areas is still performed
by laborers
with hand tools. Utilizing conventional skid loaders or skid steers as they
are commonly
known has decreased the amount of hand work involved in lawn and grounds
preparation. As a small utility loader, the skid steer is well adapted for
precision earth
moving operations in confined areas. Skid steers have hydrostatic
transmissions with
four independent wheels, which allows the skid steers to pivot in place. Skid
steers also
include hydraulic controlled lift arms and pivoting attachment assembly, which
can be
operated simultaneously while driving skid steers.
A skid steer can be fitted with various attachments to perform a variety of
earth moving functions; however, no single skid steer attachment has been
developed to
address all the operational needs of the lawn or grounds preparation industry.
Bucket
attachments are ideal for transporting loads of soil to low lying areas, but
are ill suited
for spreading the soil radially across the low lying area. The conventional
blade type
attachment allows the skid steer to grade but does not drag soil or scarify
effectively.
The bulk of conventional buckets and blade type attachments obstruct the
operators view
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of the ground being worked. Mechanical scarifying rakes have been developed
for use
with skid steers; however, these scarifying rakes have complex mechanical
parts, which
are often subjected to stress, which results in damage and often failure. The
articulated
mechanical scarifying rakes are large and cumbersome, which makes them
difficult to
operate in confined areas, such as around building and other obstacles. The
operator's
view of the ground being worked is obstructed by the bulk of the mechanical
attachments. Furthermore, the scarifying rakes are ineffective at moving soil
to low
lying areas. Since no single attachment is suitable for all the lawn
preparation functions;
namely grading, filling, leveling, scarifying and vegetation removal the skid
steer
attachments must be frequently interchanged during use at the job site.
Transporting
multiple attachments is cost ineffective.
The rake attachment of the inventions of the parent and divisional
applications
allows a conventional skid steer to be used for all lawn preparation functions
; grading,
filling, leveling and scarifying. The design of the rake attachment allows the
skid steer to
push as well as pull soil. Consequently, the rake attachment can be used to
grade soil off
of high areas, to push soil into low areas, and to scarify the soil to a
seeding ready
finish. The rake attachment eliminates the mechanical complexity of other
attachments
and the inconvenience of frequently changing attachments to perform various
earth
moving functions. The design of the rake attachment also maximizes the
operator's field
of vision for precision operation around buildings and other confined areas.
The rake attachment includes a frame and a replaceable elongated toothed rake
blade having a row of rigid spaced teeth along its forward edge. The frame
includes a
mounting plate for connecting the frame to the pivot plate of the skid loader
and a
forward lateral support member connected by a pair of spaced side members. The
rake
blade is mounted to the forward support member. The positioning of the rake
blade and
the open configuration of the frame provide the operator an unobstructed view
of the
ground being worked.
The rake attachment of Figures 8-12, in addition to the elongated frame with
spaced tines, further includes a plurality of longitudinally spaced ground
penetrating
scarifying teeth that extend from the frame at a ground engaging angle that
forms
substantially a right angle from the tines comprising the rake blade. The
scarifying teeth
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permit deep penetration and scarifying of the earth white still permitting the
tines
comprising the rake blade to level and work the soil. The scarifying teeth may
be
removed from the support member and stored when scarifying is not desired.
Accordingly, an aim of the inventions of the parent and divisional
applications is
to provide for a novel and unique mufti-purpose rake attachment for use with a
skid steer
loader.
Another aim is to provide a rake attachment for a skid steer, which is
suitable for
pushing and pulling soil during grading, filling, leveling, scarifying and
vegetation
removal.
Another aim is to provide for a low maintenance rake attachment for a skid
steer,
which reduces the complexity and number of components and allows a clear line
of
vision to the ground being worked.
Another aim is to provide for deeply scarifying the soil while at the same
time
permitting the soil to be smoothed and worked.
Still another aim is to permit scarifying teeth to be attached to the rake for
deeply
scarifying soil, but permitting such scarifying teeth to be removed when
scarifying is not
necessary.
Other aims will become apparent upon a reading of the following description.
In accordance with one aspect of the parent application, there is provided a
tool
adapted far use with a vehicle for working soil, said vehicle including a
chassis defining
an operator compartment, lift arms pivotally connected to said chassis and
movable
between a raised position and a lowered position, and a mounting plate
operatively
connected to said arms, said tool comprising a support frame, mounting means
for
connecting said support frame to said mounting plate, and a ground working
attachment
connected to said support frame, said ground working attachment configured and
arranged for contacting said soil, said support frame constituting means for
carrying said
ground working attachment to allow visual access from said operator
compartment to
said ground working attachment when said ground working attachment is in
contact with
the ground, said support frame including spaced side support members defining
an
opening therebetween, whereby soil being worked on is visually accessible from
said
operator compartment.
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In accordance with another aspect of the parent application, there is provided
a
tool adapted for use with a vehicle of the type having a chassis defining an
operator
compartment, lift arms pivotally connected to said chassis and movable between
a raised
position and a lowered position, and a mounting plate operatively connected to
said arms
and movable between an up position and a down position, said tool comprising a
support
frame and a ground working attachment, with said support frame operatively
connected
to said mounting plate, and with said ground working attachment operatively
connected
to said support frame, said ground working attachment configured and arranged
to
manipulate soil as the vehicle moves, said support frame comprising an opening
through
which an operator in the operator compartment has a substantially unobstructed
view of
soil adjacent the ground working attachment as it manipulates soil, wherein
the opening
permits a substantially unobstructed view for the operator as the lift arms
move between
the raised position and the lowered position.
In accordance with another aspect of the parent application, there is provided
a
tool adapted for use with a vehicle of the type having a chassis defining an
operator
compartment, lift arms pivotally connected to said chassis and movable between
a raised
position and a lowered position, and a mounting plate operatively connected to
said arms
and movable with respect to said arms between an up position and a down
position,
said tool comprising a support frame and a ground working attachment, with
said
support frame operatively connected to said mounting plate, and with said
ground
working attachment operatively connected to said support frame, said ground
working
attachment configured and arranged to manipulate soil as the vehicle moves,
said support
frame comprising an opening through which an operator in the operator
compartment
has a substantially unobstructed view of soil adjacent the ground working
attachment as
it manipulates soil, wherein the opening permits a substantially unobstructed
view for the
operator as the mounting plate moves between the up position and the down
position.
In accordance with one aspect of the divisional application, there is provided
a
tool for use with a skid steer for working soil, said skid steer including a
chassis, a pair
of lift arms pivotally connected to said chassis, and a mounting plate
extending between
and carried by said lift arms, said tool comprising a support frame, means for
attaching
one end of said support frame to said mounting plate, a rake blade extending
from the
CA 02479654 2005-06-09
other end of said support frame and including a support member carrying tines
for
engaging and working soil, and a set of spaced scarifying teeth extending from
said
support member at one direction with respect to the support member, said tines
extending from said support member at a direction other than the one
direction.
According to another aspect of the divisional application, there is provided a
soil
working tool for use with a vehicle having a chassis and a tool lift mechanism
movably
connected to said chassis, said tool comprising a support frame, means for
attaching one
end of said support frame to said tool lift mechanism, a plurality of tines
extending from
the support frame in a first direction, said tines configured and arranged for
engaging and
working soil, and a set of spaced scarifying teeth extending from said support
frame in a
second direction that is different than the first direction of the tines, said
scarifying teeth
configured and arranged for engaging and working soil.
According to another aspect of the divisional application, there is provided a
soil
working tool suitable for use with a vehicle having a chassis with a tool lift
mechanism
movably connected thereto, the tool comprising: a support frame; means for
attaching the
support frame to the tool lift mechanism; a tooth extending outwardly from
said support
frame in a first direction, with the tooth having an end configured and
arranged to engage
and work soil; and a tine extending outwardly from the support frame in a
second
direction, with the tine having an end configured and arranged to engage and
work soil;
wherein the first and second directions at which the tooth and the tine extend
from the
support frame and work soil define an angle therebetween.
Brief Description of the Drawings
A preferred embodiment of the invention has been depicted for illustrative
purposes only wherein:
Fig. 1 is a perspective view of a skid steer with the rake attachment of this
invention;
Fig. 2 is a top plan view of the rake attachment;
Fig. 3 is a side elevation view of the rake attachment;
Fig. 4 is a side elevation view of the skid steer with the rake attachment
grading
soil in a push/pull position;
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Fig. 5 is a side elevation view of the skid steer with the rake attachment
dragging
soil in a push/pull position and for vegetation removal;
Fig. 6 is a side elevation view of the skid steer with the rake attachment in
an
elevated position above a pile of soil;
Fig. 7 is a side elevation view of the skid steer with the rake attachment
performing
a scarifying operation;
Fig. 8 is a fragmentary perspective view of a skid steer with a rake attached
thereto
pursuant to another embodiment of the invention;
Fig. 9 is a cross-sectional view taken substantially along lines 9-9 Figure 8;
Fig. 10 is a fragmentary side elevational view of the rake according to
Figures 8
and 9 illustrated in its ground engaging and scarifying position;
Fig. 11 is an enlarged view of the circumscribed portion of Figure 9; and
Fig. 12 is a fragmentary side view of the scarifying tooth and attachment
mechanism illustrated in Figure 11.
The preferred embodiment herein described is not intended to be exhaustive or
to
limit the inventions of either the parent or divisional applications to the
precise form
disclosed herein. It is chosen and described to explain the principles of the
inventions
CA 02479654 2004-10-04
6
and their application and practical use to enable others skilled in the art to
utilize its
teachings.
Figs. 1-7 show the rake attachment 20 of this invention used with a
conventional
skid loader or skid steer 2. Rake attachment 20 is shown used on a skid steer
2
manufactured by Melroe Company under the trademark "BOBCAT" although rake
attachment 2 can be adapted for use with any make or model of skid steer.
Skid steer 2 includes a chassis 4, which has an operator's compartment 5. Skid
steer 2 preferably uses the conventional hydrostatic transmission with four
independently
driven wheels 8. The transmission is operated by two steering hand levers 6.
Chassis 4
supports two pivotal lift booms or arms 10, which are raised and lowered by a
pair of
hydraulic lift cylinders 11. Lift arms 10 are pivoted about a horizontal axis
between a
raised position (Fig. 6) and a lowered position (Fig. 7). A cross brace 12
connects arms
in front of operator compartment 5. A pivot assembly 14 is pivotally mounted
to the
front end of lift arms 10. Pivot assembly 14 includes a pivoting mounting
plate 16,
which carries an attachment connecting mechanism (not shown). A pivot cylinder
17 has
its extensible rod 18 connected between mounting plate 16 and cross member 12
as by
clevis 19. Pivot cylinder 17 shifts mounting plate 16 about a second
horizontal axis
between an up position (Fig. 6) and a down position (Fig. 7). As shown in Fig.
6,
mounting plate 16 is substantially vertical when the lift arms 10 are in the
lowered
position and rod 18 is retracted. Mounting plate 16 is angled with respect to
the
horizontal when lift arms 10 are in the Lowered position and rod 18 is
extended out from
cylinder 17. The lift and pivot cylinders are operated by two foot pedals (not
shown)
located within the operator compartment. As commonly known but not shown in
the
figures, mounting plate 16 carries a locking mechanism, which locks the
various
attachments to the mounting plate. The locking mechanism is not shown or
described in
detail and any conventional mounting mechanism can be used to secure the rake
attachment to mounting plate 16.
As common in conventional skid steers, skid steer 2 can be operated in a float
mode, wherein lift cylinders 11 are disabled to allow lift arms 10 to rest in
a lowered
position under their own weight and supported by chassis 4. Consequently, no
additional
downward force is introduced by lift cylinders 11. In the float mode, only the
pivot
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7
cylinder 17 is operative, thereby reducing the number of operation controls to
occupy
the operator's attention. Rake attachment 20 is designed to take full
advantage of this
feature during finishing operations as detailed later in this specification.
As shown in Figs. 2 and 3, rake attachment 20 includes a forward support
member 22 connect to a mounting saddle 40 by a pair of spaced side support
members
30. Forward support member 22 is preferably an elongated L-shaped angle har
with a
lower forward side 26 and a raised back 24. Forward support back 24 is
preferably of
sufficient height to prevent loosened soil from kicking over the upper edge 25
of forward
support member 22, while not substantially impairing the operator's line of
sight to the
rake blade 50.
Mounting saddle 40 is of conventional design and can be adapted for connection
to any type of mounting plate 16. Mounting saddles 40 are standardized for
various
models of skid steers 2 to accommodate various attachments. Mounting saddle 40
includes a pair of connection plates 44 connected by a cross member 42. Cross
member
42 forms a down turned upper lip 43. Each connection plate 44 has a plurality
of
mounting holes
45. Each connection plate 44 also includes a rearwardly extending peripheral
ridge 46
along the outer lower edges, which conforms to the contour of mounting plate
16.
During the mounting process of rake attachment 20 to skid steer 2, ridge 46
serves to
align mounting saddle 40 with mounting plate 16. As shown best in Fig. l, the
upper lip
43 engages the upper edge of mounting plate 16. The back surface of mounting
saddle
40 rests flat against the front surface of mounting plate 16. Mounting saddle
40 is then
locked into place against mounting plate 16 by the skid steer's locking
mechanism (not
shown) carried on mounting plate 16.
As shown in Figs. 1-3, side support members 30 are spaced apart to define a
central opening 31. Each side support member 30 includes a upper extension
part 32 arid
a lower side gussets 34 centrally connected to its upper extension part. Upper
extension
parts 32 are connected between the upper edge 25 of forward support back 24
and the
upper edges of each connection plate 44. Each side gusset 34 has four side
edges 36-39,
which define a substantially triangular configuration with a truncated forward
fourth
side. Each truncated forward edge 36 is connected as by welds to the rear face
of
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7a
forward support back 31. The opposite rear edges 37 are connected as by
welding to the
front face of each connection plate 44. The upper edges 38 are connected as by
welding
to the bottom of each upper extension members 34. The lower edged 39 extend
diagonally between the lower edge of the support back 31 and the lower edges
of each
connection plate 44.
As shown in Figs, 2 and 3, rake attachment 20 includes an elongated tined or
toothed rake blade 50 connected to a frame 30 as by fasteners 58, 59. Rake
blade 50 is
mounted to the bottom face of forward support member 22. Rake blade 50 is
defined by
interconnected rectangular panel sections 52. Each panel section 52 is bolted
to rake
support member 22 by bolts 58, which extend through aligned boxes in panel
sections 52
and lower forward side 26, and nut fasteners 59, which are affixed to bolts
58. Rake
sections 52 are connected to forward support member 30 in this fashion to
allow ready
replacement of individual panel sections. Each panel section 52 is of flat
rectangular
shape with a serrated forward edge, which forms a plurality of elongated tines
or teeth
56. Panel sections 52 are cut or cast from any durable and rigid metal, such
as iron or
steel. Panel sections 52 are preferably hardened to provide additional tensile
strength.
Teeth 56 are straight and rigid to allow the teeth to bite into hard soil
without bending or
breaking and withstand the drag force exerted by the motion of the skid steer
and the
weight of lift arms 10. The contour and spacing of teeth 56 prevent rocks,
foliage and
other debit material from collecting between the teeth, which is common in
drags and
other attachments with coiled tines.
As seen in the figures, rake attachment 20 has a relatively small and compact
design, which allows skid steer 2 to manipulate in tight areas. Rake
attachment 20 uses
no moving parts to effect all operational aspects, which enhances its valve in
field
operations. Furthermore, the design rake
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attachment 20 is easy to store or transport when detached from the skid
steer 2.
Rake attachment 20 is designed to take advantage of the float mode
operation of skid steer Z. Rake attachment 20 is fully operational without
the assistance of the lift cylinders 11. Operation of the skid steer 2 in the
float mode allows the operator to manipulate rake attachment 20 through
all of its operational positions using only the pivot control foot pedal.
Consequently, the operation of the rake attachment and skid steer is
simplified. Using only the pivot control pedal to perform the ground work
simplifies the task of the operator and avoids confusion between the lift
and pivot control pedals. Since rake attachment 20 can operate solely with
pivot cylinder 17, its operation is less taxing on the skid steer's hydraulic
systems, which translates into increased performance and life span of skid
steer 2.
Fig. 6 shows skid steer 2 with rake attachment 20 in the elevated
position. In the elevated position, pivot cylinder 17 draws mounting plate
16 back towards skid steer 2, so that mounting plate 16 is substantially
vertical and perpendicular to the ground. In the elevated position, rake
blade 50 is spaced two to three feet above the ground and approximately
three feet from the bottom edge of mounting plate 16. The lower diagonal
edges 39 of side gussets 34 are slanted upward at approximately a 55
degree angle to the ground. 'The upward slant of lower diagonal edges 39
provides front end clearance, so that skid steer 2 can be positioned adjacent
to small piles of earth with teeth 56 extend over the top of a pile of soil
70,
as shown in Fig. 6. In the elevated position, the operator has a clear view
of the worked ground and soil 70 around side support members 30 and
though central opening 31.
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Fig. 7 shows skid steer 2 with rake attachment 20 in the lowered or
scarifying position. In the scarifying position, pivot cylinder 17 fully
extends
mounting plate 16 so that mounting plate 16 is pivoted beyond horizontal
and rake blade 50 engages the ground perpendicularly. The rotation of
$ mounting plate 16 and the connected rake attachment 20 to the scarifying
position forces lift arms 10 to be raised slightly from their lowered
position.
The weight of lift arms 10 and the vertical position of rake blade 50,
provides an ideal position for scarifying soil. Under the influence of
gravity, the weight of lift arms 10 is transferred directly through rake blade
50. The combined weight of lift arms 10 and rake attachment 20 embeds
teeth 56 into the soil and scars the soil as the skid steer moves backward.
In scarifying position, lift arms 10 and mounting plate 16 are substantial
horizontal and provide a clear unobstructed view of the entire rake blade
50. Consequently, the operator can directly monitor the depth and
effectiveness of each skid steer pass.
Figs. 4 and 5 show the skid steer 2 with rake attachment in an
intermediate or push/pull position. Again as seen in Figs. 4 and 5, the
design of rake attachment 20 provides the operator with a clear view of the
approximate area of ground being worked. The soil can be viewed over
the top of rake attachment 2(), around side support members 30, or through
central opening 31. In the push/pull position, mounting plate 16 is pivoted
between its up and down positions, wherein lower diagonal edges 39 of side
gussets 34 are approximately horizontal and parallel with the ground. In
the push/pull position, rake blade 50 engages the ground at an acute angle,
approximately at a 30 degree angle. The angle at which the rake blade
engages the ground can be adjusted by further lowering mounting plate 16.
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As pivot plate 16 rotates past the rake blade's contact point with the
ground, lift arms 10 are slightly raised from their lowered position to place
the weight of the arms on teeth 56.
In the push/pull position, rake attachment 20 can be used to grade
soil by pushing rake blade 50 forward or to drag soil by pulling soil
backward. As shown in Fig. 4, forward movement of skid steer 2 pushes
teeth 56 across the top layer of soil, which turns up a volume of soil along
the way. The loosened soil gathers above rake blade 50 and in front of
forward support member 22 as skid steer 2 moves forward. Forward
10 support back 31 prevents the soil from moving over the top of the rake
support, and does not obstruct the operators view of the ground being
worked or rake blade S0. Rocks embedded in the soil are drawn up and
accumulate on the top of forward support member 22. The contour,
spacing and rigidity of teeth 56 allow rocks to be dislodged from the soil,
but not lodged between teeth 56. Conventional rakes use coils chisels or
tines, which flex under the friction of the skid steer movement, allowing
rocks to lodge in between the chisels and tines. Adjusting the angle at
which rake blade 50 engages the ground varies the amount of soil graded
with each pass.
Fig. 5 shows soil dragged behind rake attachment 20 as skid steer 2
moves backward. As skid steer 2 moves backward, a small volume of soil
is pulled backward by the under side of rake blade 50 and forward support
member 22. The spacing between teeth 56 allows small amounts of loose
soil to pass through, which gives a raked soil appearance. Increasing or
decreasing the angle of pivot plate 16 increases or decreases the attitude of
rake attachment 20 to vary the amount of soil dragged.
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Referring now to the alternate embodiment of Figs. 8-12, elements
the same or substantially the same as those in the embodiment of Figs. 1-7
retain the same reference character, but increased by 100. Referring now
to Figs. 8-12, a plurality of tubular sockets indicated by the numeral 160 are
spaced evenly along the back 24 of support plate 122. Each of the sockets
160 define a vertically extending opening 162 which slidingly receives a
scarifying tooth 164. Each of the scarifying teeth are substantially
rectangular bars having a tapering ground penetrating end 166 which joins
v~rith side edge 168 at corner 170. As will be discussed hereinafter, the
tapering end 166 and edge 170 permit the scarifying teeth 164 to chisel into
hard ground to facilitate scarifying. Each of the teeth 164 is provided with
an aperture which registers with apertures 174, 176 on the opposite sides of
each of the sockets 160. A retaining pin 178 is inserted through the
apertures 174, 176 and through the aperture in the corresponding tooth 164
to retain the corresponding scarifying tooth 164 in its corresponding socket
160. The retaining pin 178 is maintained in its position by a finch pin 180
which is received within an aperture 182. A ring 184 extends through an
opening in the finch pin and is freely movable with respect thereto. Ring
184 is attached to another ring 186 on the other end of the pin 178 by a
chain 188. Accordingly, each tooth 164 is installed in its corresponding
socket 160 by inserting the pin 178 through apertures 174, 176, and through
the corresponding tooth 164. The finch pin 180 is then installed in the
aperture I82 with the ring 184 deflected out of the way. When the ring 184
is released, it sags to a point that prevents the linch pin 180 from vibrating
out of the aperture 182. A washer 190 is installed on the other end of the
pin to prevent the pin from being inserted ixato the apertures 172, 174, 176
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lla
so far that the socket 160 interferes with the ring 186.
In operation, the scarifying teeth penetrate the ground when the
support member 122 is disposed at any ground working angle, such as that
illustrated in Fig. 10. Each of the teeth 164 are rectangular bars of
$ substantial thickness and thus, because of beveled edge 160, are able to
chisel into the ground and scarify the ground during both forward and
backward movements of the skid steer. As the teeth 164 are scarifying the
ground, the tines 156 smooth and work the ground as it is being scared.
If scarifying is not desired, the teeth 164 may be removed from the fork
member 122 by removing the finch pin 180 of each tooth and then
removing retaining pin 178. The teeth 164 can then be removed from their
sockets 160, and are then conveniently stored on pins 192 which project
from lower support braces 194 which are a part of side support members
130 and extend between back 124 and lower cross bar 196 which
interconnects the side support members 130 and also extends between the
connection plates 144.
Scarifying can also be accomplished with the scarifying teeth 164
removed by moving the rake to the scarifying position illustrated in Figure
5 to use the tines 156 for scarifying, but the tines 156 are unable to
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penetrate the ground to the same depth as do the scarifying teeth 164 and
obviously the tines 156 are not then available to level and work the soil as
it is scarified.
