FROZEN TOP SOIL CUTTER

OUTIL DE DECAPAGE DE SOLS GELES

English Abstract

A device for cutting, fracturing and pulverizing top soil to a predetermined
depth, whereby by the top soil can subsequently be collected by conventional means. The
device comprises a frame being in the shape of a V with two wings rearwardly and sidewardly
extending from a forward, central point, the frame to be carried behind a tractor, a plurality
of spaced cutting wheels rotatably suspended from the frame at the same distance from the
frame, the wheels of sufficient size and strength to cut frozen soil to a predetermined depth,
the wheels oriented in parallel, straightforward relationship with respect to the frame, a first
of the wheels positioned at the central point and the other wheels spaced outwardly and
rearwardly on each side of the first wheel. The device comprises means associated with the
frame to depress the cutting wheels to a predetermined depth in the frozen soil and the wheels
spaced from each other so that, in operation, the first wheel vertically cuts the soil along a
center line, to the predetermined depth, and wheels on each side of the first wheel
progressively vertically cut and horizontally fracture towards the center line the soil to the
predetermined depth. A device according to the present invention provides a simple design
for cutting frozen top soil to a predetermined depth. The device according to the present
invention is one which produces relatively low wear of the functional parts, relative to
conventional devices. It provides increased integrity of surface soil when stripping in frozen
ground conditions.

French Abstract

Cette invention concerne un dispositif servant à défoncer, briser et pulvériser la terre végétale jusqu'à une profondeur prédéterminée en vue du ramassage de cette terre selon des moyens conventionnels. L'objet de l'invention comprend un bâti en forme de V dont les deux ailes s'étendent vers l'arrière et les côtés à partir d'un point central, ledit bâti étant à monter derrière un tracteur, et des roues de travail du sol suspendues à une même distance du bâti. Ces roues ont diamètre et une résistance appropriés pour défoncer la terre végétale gelé jusqu'à une profondeur prédéterminée; elles sont toutes parallèles à l'axe de symétrie longitudinal du bâti, la première étant placé à la pointe du V et les autres progressivement décalées vers l'arrière et les côtés. Le dispositif objet de l'invention comporte un moyen pour enfoncer les roues à une profondeur prédéterminée dans le sol gelé, roues qui sont disposées de manière que la première fasse une entaille verticale le long de l'axe de symétrie longitudinal du bâti et que les autres fassent une entaille parallèle à la première et pousse le sol vers la première entaille pour le briser jusqu'à une profondeur prédéterminée. Le dispositif objet de l'invention se caractérise par la simplicité de mode de défoncement d'un sol gelé jusqu'à une certaine profondeur et par un mode de travail qui produit relativement peu d'usure par rapport aux engins conventionnels. En plus, le décapage par temps de gel à l'aide de ce dispositif a des effets moins destructeurs sur le sol laissé en place. et compriment.

Claims

-9-
WE CLAIM:
1. A device for cutting, pulverizing and fracturing frozen top soil to a
predetermined depth, whereby the top soil can subsequently be collected by conventional
means, the device comprising:
(a) a frame, the frame to be carried behind a tractor;
(b) a plurality of spaced cutting wheels extending in "V"-formation,
rearwardly and sidewardly extending from a forward, central point,
rotatably suspended from the frame at the same height from the frame,
the wheels of sufficient size and strength to cut frozen soil to a
predetermined depth, the wheels oriented in parallel, straightforward
relationship with respect to the frame, a first of the wheels positioned
at the central point and the other wheels spaced outwardly and
rearwardly on each side of the first wheel; and
(c) means associated with the frame to depress the cutting wheels to a
predetermined depth in the frozen soil;
the wheels spaced from each other and positioned so that, in operation, the first wheel
vertically cuts the soil along a center line, to the predetermined depth, and wheels on each side
of the first wheel progressively vertically cut and horizontally fracture it towards the center line
to the predetermined depth.

- 10-
2. A device according to claim 1 further provided with connection means
associated with the frame to operatively connect the frame to a hydraulic support system of a
tractor, in operation when the frame is thus connected, the hydraulic system providing the
downward pressure and height control necessary to have the wheels cut the soil to the
predetermined depth as the frame is drawn by the tractor along a distance.
3. A device according to claim 1 wherein a plurality of shanks are suspended from
the frame, the shanks being downwardly and forwardly oriented and positioned so as to assist
in sinking the cutting wheels to the predetermined depth and maintaining them at that depth
during the cutting operation.
4. A device according to claim 1 wherein the cutting wheels are equally spaced
from adjacent cutting wheels laterally a distance of from about 4 inches to about 8 inches.
5. A device according to claim 4 wherein the cutting wheels are about 1 inch thick
and have a diameter in the range of from of about 12 inches to about 24 inches, with sharpened
peripheral cutting edges.
6. A device according to claim 5 wherein the cutting wheels are spaced at a lateral
distance of about 8 inches from adjacent cutting wheels.
7. A device according to claim 2 wherein the device is further provided with depth

-11-
control means for the cutting wheels. the depth control means selected from the group
comprising sliding feet and support wheels.

Description

CA 02237001 1998-07-10
TITLE OF THE INVENTION
FROZEN TOP SOIL CUTTER
FIELI) OF INVENTION
This invention relates ta a device for cutting frozen soil to a predetermined
5 depth.
BACKGROUND OF THE INVENTION
Present day outdoor construction requirements, in order to address
environmental concerns, require replacement of the surface soil layer after excavation and
construction has been completed. In northern climates, often outdoor construction takes place
10 during winter months when the soil is frozen and may be covered by a blanket of snow. In
order to loosen and salvage surface soil in such conditions, without mixing lower soil which
may for instance be of clay or other coIrlposition, has proven to be a difficult challenge. In the
past, several different methods have been used.
For example, a tractor with a ripper has been used to rip the surface soil in
15 order to loosen the soil so that the material can be recovered by way of a blade or a bucket on
a hoe. Such an approach however does not permit maintenance of the stripping depth,
resulting in admixing of surface soil with subsoil. The result is degradation of the surface soil.

CA 02237001 1998-07-10
Another approach has been to use self-propelled stripper/ditcher/trencher
devices in order to salvage surface soil. These machines are very good at m~int~ining surface
soil depth. Trenchers for example have a track of buckets that circulate on a large wheel
similar to a water wheel. They are however very expensive to run and m~int~in. A self-
propelled stripping device is described and illustrated in laid-open C~n~ n patent application
Serial No. 2,132,078 of Merilainen pub]ished March 16, 1995. A trencher device is described
for example in U.S. Patent No. 4,395,834 of Davison issued August 2, 1983 and the PCT
application of Disney published under ]'ublication No. WO91/14836, on October 3, 1991.
Hoes are often used with frost buckets to strip surface soil. This method is very
time consuming and costly. Admixing of surface soil with subsoil still remains a problem with
this method.
Other patents of general background interest disclosing soil cutting devices of
one form or another include C~n~ n laid-open patent application Serial No. 2,089,705 of
Roggenbuck et al, published November 2, 1993, and U.S. Patents Nos. 5,437,337 ofDietrich,Sr., issued August 1, 1995 and 2,703,518 of Whitmore, issued March 8, 1955. Most
of these patents relate to cutters which are merely pulled by tractors and are intended for
unfroz;en soil. Also of background interest are U.S. Patent No. 2,371,924 of Scarlett issued
March.20, 1945, U.S. Patent No. 2,269,724 of Linkogel issued January 13, 1942, U.S. Patent
No . 3,752,238 of Chilton issued August 14, 1973, U . S . Patent No . 4,057,112 of Taylor issued
Novernber 8, 1977, U.S. Patent No. 4,203,494 of Hansen issued May 20, 1980, U.S. Patent
No. 4,548,276 of Linger issued October 22, 1985, U.S. Patent No. 5,333,694 of Roggenbuck
et al issued August 2, 1994, U.S. Patent No. 4,506,740 of Carter issued March 26, 1985 and

CA 02237001 1998-07-10
U.S. E'atent No. 5,649,602 of Bruce issued July 22, 1997. With frozen soil, most of these
devices would simply skid on the soil surface, and would not act to cut into the soil, or, in
instances where such devices would cut into the frozen soil, they would result in admixing of
surfac~ soil with subsoil and not m~int~in adequately the required cutting/stripping depth.
It is an object of the present invention to provide a device which can loosen and
pulverize frozen top soil in a timely fashion while m~int~ining soil quality, and hence depth
control, better than previously known devices.
SUMMARY OF THE INVENTION
In accordance with the present invention there is a provided a device for cutting,
fracturing and pulverizing top soil to a predetermined depth, whereby by the top soil can
subsequently be collected by conventional means. The device comprises a frame, extending
rearwardly and to the sides from a forward, central "V"-formation, the frame to be carried
behind a tractor, with a plurality of spaced cutting wheels rotatably suspended from the frame
at the same height from the frame. The wheels are of sufficient size and strength to cut frozen
soil to a predetermined depth. The wheels are oriented in parallel, straightforward relationship
with respect to the frame. The first oi- the wheels is positioned at the central point and the
other wheels are spaced outwardly and rearwardly on each side of the first wheel and
positioned so that, in operation, the first wheel vertically cuts the soil along a center line, to
the predetermined depth, and wheels on each side of the first wheel progressively vertically
cut the soil to the predetermined depth and horizontally fracture it towards the center line.

CA 02237001 1998-07-10
The device further comprises means as~ociated with the frame to depress the cutting wheels
to the predetermined depth in the frozen soil.
In a preferred embodiment of the present invention, connection means are
associated with the frame to operatively connect the frame to a hydraulic support system of a
tractor. In operation when the frame is thus connected, the hydraulic system provides the
downward pressure and height control necessary to have the wheels cut the soil to the
predetermined depth as the frame is drawn by the tractor.
As will be described in more detail subsequently, the device according to the
present invention provides a simple design for cutting frozen top soil to a predetermined depth.
The dc vice according to the present invention is one which produces relatively low wear of the
functional parts, relative to conventional devices. It provides increased integrity of surface soil
when stripping in frozen ground conditions.
BRIEF DESCRIPTION OF THE DRAWINGS
The following is a description by way of examples of preferred embodiment of
the present invention, reference being rnade to the accompanying drawings in which:
FIGURE 1 is a perspective view of a tractor carrying a device for cutting,
pulverizing and fracturing frozen top soil in accordance with the present invention.
FIGURE 2 is a schematic plan view, from below, of the device of FIGURE 1.
FIGURE 3 is a partial elevation side view of the device of FIGURE 1.
FIGURE 4 is a schematic: plan view, from below, of an alternative embodiment

CA 02237001 1998-07-10
of the device according to the present i:rlvention incorporating shanks with cutting wheels.
FIGURE 5 is an elevation partial view of the device of FIGURE 3.
FIGURE 6 is a side view of one of the cutting wheels of the device in
accordance with the present invention.
FIGURE 6a is a section view along a diagonal line of the cutting wheel of
Figure 6.
While the invention will be described in conjunction with the illustrated
embodiments, it will be understood tlhat it is not intended to limit the invention to such
embodiments. On the contrary, it is intended to cover all alternatives, modifications, and
equivalents as may be included within the spirit and scope of the invention as defined by the
appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the drawings, similar features have been given similar reference numerals.
Turning to Figure 1 there is illustrated a device 2 for cutting, fracturing and
pulverizing frozen top soil to a predetermined depth, in accordance with the present invention
carriecl behind a tractor 4 as will be described in more detail subsequently.
The device comprises a frame 6.. A plurality of spaced, cutting wheels 12
extend rearwardly and sidewardly from a forward, central point 10, in "V" configuration and
are rotatably suspended from supports 14 so that wheels 12 are all carried at the same distance
20 from l:he frame. The wheels are of sufficient size and strength to cut frozen soil to a

CA 02237001 1998-07-10
- 6 -
predetermined depth. The wheels are preferably about 1 inch in thickness and have a diameter
of about 12 inches up to about 24 inches or more, with sharpened peripheral cutting edges 16
as can be seen in Figure 6. The cutting wheels 12 are spaced approximately the same distance
from adjacent cutting wheels, that dista.nce preferably being about 4 to about 8 inches. The
5 wheels are oriented in parallel, straightforward relationship with respect to the frame, so that
when frame 6 is pulled by tractor 4, the wheels cut in the same direction as the tractor is
travelling.
As can be seen in Figure 2, a first of cutting wheels 12 is positioned at the
centra]L point 10 of frame 6, and the other wheels 12 are spaced outwardly and rearwardly on
10 each side of that first wheel 12. The laleral distance between adjacent wheels is important to
achieve the desired operation of the device, namely that the first wheel vertically cuts the soil
along a center line, to the predetermined depth, and wheels 12 on each side of the first wheel
then progressively vertically cut and horizontally fracture towards the center line the soil to the
predetermined depth.
In order to ensure that the wheels cut the soil to the predetermined depth,
applopliate means 18, in the illustrated embodiment being the tractor's hydraulic support
system 20, are provided. It is nPcess~ry to have sufficient downward pressure exerted by
hydraulic system 20, to have the wheels cut the soil to the predetermined depth as the frame
is drawn by the tractor along a distance, and m~in~in the cutting wheels at that cutting depth
20 in the soil.
While it is preferred that a tractor's hydraulic system 20 provide the downward
pressure and depth control for the cutting wheels, it is envisaged that other means may be

CA 02237001 1998-07-10
provided, for instance through applopriate adjustable weight means associated with frame 6
(not illustrated).
In operation, the lead cutting wheel 12 cuts and fractures the soil. It provides
initial penetration and cutting of the soil under pressure from the hydraulic system 20 of tractor
5 4. The following cutter wheels 12 slice the soil and cause the soil to fracture inwardly towards
the center line where the soil has already been disturbed. The wheels cut vertically and the soil
fractures horizontally. This process can be repeated until a desired width soil of cut aggregat
has been formed.
In the alternative embodiment of device 2 in accordance with the present
10 invent-ion, as illustrated in Figures 3 and 4, certain of the wheels are replaced with shanks 22,
placed at applop~iate locations between cutting wheels 12 as illustrated. The shanks 22 are
intendled to rip and fracture the soil and provide, in the case of lead shank 22, initial
penetration and downward pressure. The following cutter wheels 12 slice the soil and cause
the soil fracture inwardly towards the c:enter line where the soil has already been disturbed.
15 The wheels cut vertically and soil fractures horizontally.
Any number of depth control mech~ni~m.~ can be used to assist maintenance of
the cul:ting, pulverizing and fracturing of the soil to the predetermined depth, such as sliding
feet 24 or wheels (not illustrated), with conventional height adjustment means 26
The size of frame 6 and number and positioning of wheels 12 may be varied,
as determined by the tractor (or other machine) to which it is attached and the soil conditions
in which it is intended to operate.
It will be understood that, through use of a device 2 as described and illustrated,

CA 02237001 1998-07-10
benefils arise over conventional soil stripping machines including:
(1) increased integrity of surface soil when stripping unfrozen ground;
(2) simplicity of design allowing for cost effective production;
(3) increased speed of stripping is greatly increased;
(4) low wear relative to conventional devices; and
(5) accurate depth control.
Thus, it is apparent that there has been provided in accordance with the
invention a device for cutting frozen soil to a predetermined depth that fully satisfies the
objects, aims and advantages set forth above. While the invention has been described in
10 conjunction with illustrated embodiments thereof, it is evident that many alternatives,
modifications and variations will be apparent to those skilled in the art in light of the foregoing
description. Accordingly, it is intended to embrace all such alternatives, modifications and
variations as fall within the spirit and b:road scope of the invention.

Representative Drawing