Note: Descriptions are shown in the official language in which they were submitted.
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ICE PULVERIZING KNIFE AND ICE PULVERIZING DEVICE COMPRISING
AN ICE PULVERIZING KNIFE
TECHNICAL FIELD
[0001] The present disclosure relates to the field of ground surface de-
icing. More particularly, the present disclosure relates to an ice pulverizing
knife
for pulverizing ice from a ground surface, and to an ice pulverizing device
comprising an ice pulverizing knife.
BACKGROUND
[0002] Keeping ground surfaces, particularly roads and airport runways,
free of ice has long been a major problem in geographical regions where
temperatures drop below freezing. Over the years, many methods and devices
have been developed and constructed to clear such ground surfaces of ice.
[0003] Some methods of clearing ground surfaces of ice include
scarifying the ice, which consists in cutting grooves into the ice to increase
the
surface area that is exposed to warming rays of the sun. Numerous devices
with rake attachments or cutter blades are known for scarifying or raking
ground
surfaces. However, in many cases, such methods do not provide the desired
result quickly enough since the ice is not completely removed, but merely
scarred, and the sun has to perform the remaining of the work.
[0004] Another method consists in melting the ice through a chemical
reaction. Chemical methods of de-icing ground surfaces include spraying a de-
icing fluid or scattering de-icing crystals or solids over the ice-covered
surface.
One common disadvantage of these two methods is that, as the ice melts, the
water flows toward low-lying areas, entraining the de-icing chemicals with it.
This effectively removes the de-icing chemicals from high-lying areas.
Therefore, to gain efficiency, the chemical method needs to be combined with
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the scarifying method, which grooves tend to retain the chemicals. A
consequent drawback is that some chemicals, such as salt, do not perform
properly when temperatures are too cold. Furthermore, when the ice melts and
water runs on the side of the road or runway, the water transporting the
chemicals is absorbed by the surrounding ground, which may be detrimental to
the environment.
[0005] Still another method consists in using various types of devices
having ice cutting and / or ice crushing capabilities for removing ice from
the
ground, without assistance from warming rays of the sun or from chemicals.
However, such devices usually do not have the capability to treat surfaces
covered by very hard ice. For instance, some devices cannot operate at all
when the ice is too hard and / or too thick. Other devices are only capable of
removing a partial layer of ice when the ice is too hard, thus leaving a
remaining
layer of ice on the ground. Such devices need to treat the same surface of ice
several times, in order to completely remove a layer of ice covering that
surface.
[0006] There is therefore a need for an ice pulverizing knife and an ice
pulverizing device comprising an ice pulverizing knife.
SUMMARY
[0007] According to a first aspect, the present disclosure provides an ice
pulverizing knife for pulverizing ice from a ground surface. The knife
comprises
a frame and a plurality of blades secured to the frame. The frame has a
substantially circular base and comprises a top having a socket. The socket is
adapted for mechanically coupling the frame with a vertical drive shaft. A
rotation of the vertical drive shaft results in a circular rotation of the
frame. The
frame also comprises the base for engaging with the ice on the ground surface.
The frame further comprises at least one opening between the top and the
base. Each blade partially extends outside the frame and partially extends
inside the frame. A bottom surface of each blade engages with the ice on the
ground surface for cutting the ice. Ice cut by the portion of each blade
partially
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extending inside the frame is evacuated from the frame through the at least
one
opening.
[0008] According to a second aspect, the present disclosure provides an
ice pulverizing device for pulverizing ice from a ground surface. The ice
pulverizing device comprises at least one ice pulverizing knife and a
propulsion
mechanism. The propulsion mechanism comprises the vertical shaft. The
socket of the at lest one ice pulverizing knife is mechanically coupled with
the
vertical drive shaft in such a manner that upon rotation of the vertical drive
shaft, the at least one ice pulverizing knife rotates.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] In the appended drawings:
[0010] Figures 1A and 1B are a front elevation view of an ice pulverizing
knife;
[0011] Figure 2 is a top elevation view of the ice pulverizing knife of
Figure 1;
[0012] Figure 3 is a bottom elevation view of the ice pulverizing knife of
Figure 1;
[0013] Figure 4 is a front elevation view of the ice pulverizing knife,
according to another embodiment;
[0014] Figure 5 is a front elevation view of an ice pulverizing knife in
accordance with yet another embodiment;
[0015] Figure 6 is a top elevation view of the ice pulverizing knife of
Figure 5;
[0016] Figure 7 is a bottom elevation view of the ice pulverizing knife of
Figure 5;
[0017] Figure 8 is a front elevation view of the ice pulverizing knife
according to yet another embodiment.;
[0018] Figure 9A is a bottom view of a ice pulverizing device in
accordance with a first aspect;
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[0019] Figure 9B is a bottom view of the ice pulverizing device in
accordance with a second aspect; and
[0020] Figure 10 is a flow diagram of a method of operating the ice
pulverizing device.
DETAILED DESCRIPTION
[0021] The foregoing and other features will become more apparent upon
reading of the following non-restrictive description of illustrative
embodiments
thereof, given by way of example only with reference to the accompanying
drawings. Like numerals represent like features on the various drawings.
[0022] Various aspects of the present disclosure generally address one
or more of the problems related to ground surface de-icing.
[0023] Reference is now made to Figures 1A, 1B, and 2 - 8 concurrently,
which illustrate an ice pulverizing knife 10 for pulverizing ice from a ground
surface.
[0024] The knife 10 comprises a frame 20. The frame 20 comprises a
substantially circular base 30. Although shown as being perfectly circular on
the
Figures, the present ice pulverizing knife 10 could alternately have another
type
of symmetric shape, such as for example an hexagon, a heptagon, an octagon,
etc. Although not absolutely essential, the base 30 should be shaped so as to
reduce impacts exerted on the ice pulverizing knife upon rotation thereof, to
ensure stability and durability of the latter. Irregular base shapes will
result in a
series of impact which is not desirable.
[0025] The base 30 engages with the ice on the ground surface. Figure
1A illustrates the knife 10 alone; while Figure 1B illustrates the knife 10
operating on a layer of ice 32 on the ground 34, with the base 30 engaging the
layer of ice 32. The ground 34 may consist of a street, a sidewalk, a landing
runaway, a parking lot, etc. Although the ice pulverizing knife 10 is shown on
Figure 1B as being within the layer of ice 32, those skilled in the art will
understand that the ice pulverizing knife 10 may reach such a position only
after
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it has been rotated long enough to pulverize the ice in the layer of ice 32
where
it is located.
[0026] The frame 20 could be built with several interconnected
components as shown on the Figures, or be molded into one piece. The frame
20 comprises a top 40 having or defining a socket 50. The socket 50 is adapted
for mechanically coupling the frame 20 with a vertical drive shaft (not
represented in the Figures). Rotation of the vertical drive shaft results in a
circular rotation of the frame 20, and thus rotation of the ice pulverizing
knife 10.
[0027] The ice pulverizing knife 10 comprises a plurality of blades 70.
The plurality of blades 70 may be secured to the frame 20 or be part of the
frame 20. When the blades 70 are secured to the frame 20, it is possible to
replace one or several blades, while when the blades are part of the frame 20,
it
is necessary to replace the ice pulverizing knife when the blades 70 become
too
dull, broken or overused.
[0028] The blades 70 radially extend from the frame. The blades 70 may
radially extend inside the frame 20 only as shown on Figure 7, radially extend
outside the frame 20 only as shown for example on Figure 1A, radially extend
partially inside and partially outside the frame 20 as shown on Figure 3, or a
combination thereof. The length of the blades radially extending from the
frame
20 may vary, be identical. Alternately, the blades radially extending outside
the
frame 20 may be shorter or longer than the blades 70 radially extending within
the frame 20. The blades 70 are positioned with respect to the base 30 of the
frame 20 so as to provide engagement of each blade 70 with the ice on the
ground surface for cutting the ice thereabout. Furthermore, the blades 70 do
not
extend below the base of the frame 20 so as to avoid damaging the surface
under the layer of ice. The blades 70 are preferably positioned at a regular
interval along the base of the frame 20, so as to provide even resistance on
the
drive shaft (not shown), and thereby avoid disbalancing of the ice pulverizing
knife 10 or premature misalignment of the socket 50. The blades 70 may be
made of a metal or alloy, or of any material very resistant to abrasion, such
as
for example steel, iron, i.e. any material that resists or tolerates abrasion
with
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solid surfaces such as cement, concrete, asphalt, gravel, sand and the like.
The blades 70 may be sharp or dull, depending on the type of material used.
To increase their strength and efficiency, the blades 70 may be positioned at
an
angle a with respect to a center of the frame 20, as shown on Figure 1A. When
the ice pulverizing knife is to be used with a drive shaft turning in the
clockwise
direction, an angle a with respect to the center of the frame 20, as shown on
Figure 4 is recommended, while when the ice pulverizing knife is to be used
with a drive shaft turning in the counterclockwise direction, an angle cc with
respect to a center of the frame 20, as shown on Figure 1A is recommended.
[0029] Figure 1B
illustrates the result of the circular rotation of the blades
70, i.e. pulverizing the layer of ice 32 up to or almost up to the ground 34.
Ice
pulverized by the blades 70 radially extending inside of the frame 20 is
expelled
from the frame 20 thereby through at least one opening 60 between the top 40
and the base 30. Furthermore, upon
displacement of the rotating ice
pulverizing knife 10 along the ground 34, ice pulverized by the blades 70
radially extending outside of the frame 20 gradually enters the inside of the
frame 20, and is also expelled through the at least one opening 60.
[0030] Although four
openings are shown on the Figures, the present ice
pulverizing knife 10 is not limited to such an implementation. Depending on
the
height of the frame 20, the number of blades 70 and the location of the blades
70 either inside and/or outside of the frame 20, a different number of
openings
60 could be used. Alternately, some of the opening could be located at various
height along the frame 20. When no blades 70 is present inside the frame 20, a
scraper (not shown) could be used to help in expelling the pulverized ice
outside of the frame 20 through the opening(s) 60.
[0031] The ice
pulverizing knife 10 may further comprise a plurality of
upper blades 70' on an upper portion of the frame 20. The upper blades 70'
pulverize an upper portion of the layer of ice upon displacement of the
rotating
ice pulverizing knife 10 along the ground 34. The upper blades 70' may be
disposed at a fixed interval around the frame 20. The upper blades 70' may be
located above the blades 70, or in between blades 70. The upper blades 70'
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may be positioned at the angle a as previously discussed, or be aligned with a
central line of the frame 20. There may be more, less or an equivalent number
of upper blades 70' and blades 70. The upper blades 70' may be made of a
similar material as the blades 70, or made of a different material. The upper
blades 70' may be removable from the frame 20 as shown on the Figures, or
made part of the frame 20.
[0032] The base of the frame 20 may further be provided with a series of
notches 90. The notches 90 may be disposed around the base of the frame 20,
and may engage the layer of ice. The notches 90 may groove the layer of ice,
so as to further assist the blades 70 in pulverizing the ice.
[0033] In a particular aspect, each blade 70 is removably secured to the
frame 20, to facilitate the replacement of worn out blades 70. Mechanisms for
removably securing the blades 70 are well known in the art, and include for
example hinges simultaneously secured to the blades 70 and to the frame 20 by
means of screws and nuts. It may be preferable to have the securing
mechanisms attached to the portion 72 (illustrated in Figure 3) of each blade
70
extending inside the frame 20, to avoid a degradation of the performances of
the ice removing function of the blades 70. Alternatively, slots (not
represented
in the Figures) may be provided in the frame 20 for inserting the blades 70.
The
slots may have a specific shape for maintaining the blades 70 engaged in the
base 30 when in use for removing ice, while allowing disengagement of the
blades 70 from the base 30 via a tool (e.g. a hammer) when not in use for
removing ice. Other conventional methods of assembly may also be used.
[0034] In another particular aspect, each blade 70 is integral to the frame
20. For example, the blades 70 are welded to the frame 20. This configuration
may provide a better resistance to the pressure exerted on the blades 70 while
pulverizing ice compared to the removable blades previously discussed.
[0035] A configuration with five blades 70 radially extending partly inside
and partly outside of the frame rotating at 500 rpm or higher has been tested,
with blades positioned at an angle a of 45 degrees and four openings has
provided excellent results in terms of ice pulverizing efficiency, balance of
the
8
frame 20 and resistance to the pressure exerted on the blades 70 while
pulverizing ice. The tested configuration pulverized ice layers of up to 5
inches
thick, transforming pure ice into snow. The rotating ice pulverizing knife 10
was
displaced along the ground surface 34 at a speed of 5 mph.
[0036] Depending on the selected implementation, the frame 20 may be
integrally made of a single material moulded to the proper shape.
Alternatively,
the base 30 may be made separately and assembled with the rest of the frame
20, to become an integral part of the frame 20. For example, the base 30 may
be welded to the rest of the frame 20. Alternatively, hinges may be
simultaneously secured to the base 30 and to the rest of the frame 20 by means
of screws and nuts. Other conventional methods of assembly may also be used.
Similarly, the top 40 may be made separately and assembled with the rest of
the frame 20, to become an integral part of the frame 20. The frame 20 may be
integrally made of a metal, for example steel. Alternatively, different parts
of the
frame 20 (e.g. the based 30 and / or the top 40) may be made of different
materials having specific characteristics adapted to the functionalities of
each
particular parts.
[0037] In another aspect shown on Figure 8, the ice pulverizing knife
is
further provided with rotating wheels 990 along its base, so as to better
protect
the ground surface on which the rotating ice pulverizing knife 10 is used. The
rotating wheels may be made of metal, rubber, or any other appropriate
material. The rotating wheels 990 may be fixed to the base 30, or may be
thereto attached.
[0038] Reference is now made concurrently to Figures 9A and 9B, which
are exemplary bottom views of different aspects of an ice pulverizing device
100. The ice pulverizing device 100 includes at least one ice pulverizing
knife
10. As shown on Figure 9A, the ice pulverizing device 100 includes four ice
pulverizing knives 10 in linear alignment perpendicular to a direction 110 of
movement of the ice pulverizing device 100. Figure 9B depicts five ice
pulverizing knives 10 positioned in two rows aligned perpendicular to the
direction 110 of movement of the ice pulverizing device 100. The ice
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pulverizing device 100 may include any number of ice pulverizing knives 10 in
order to cover the area from which the ice needs to be pulverized. For
example, the ice pulverizing device 100 may include a number of ice
pulverizing
knives 10 positioned so as to pulverize ice over a width corresponding to the
width of the tractor or vehicle with which it is used. For example, in the
case of
sidewalk snow removal vehicles, the ice pulverizing device 100 may include 2
or 3 ice pulverizing knives 10 pulverizing ice over a width of the sidewalk
snow
removal vehicle. In another example, the ice pulverizing device 100 may be
added to a vehicle for removing snow and ice from streets, and may include 6-
ice pulverizing knives 10 positioned in one or two rows, and pulverizing ice
over a width of the vehicle or a snow removal blade thereof.
[0039] The ice pulverizing device 100 may be presented as an implement
to be used with a tractor or a vehicle. In such a case, the ice pulverizing
device
100 is equipped with a power transmission coupler, such as for example a
Power Take Off (PTO) coupler, acting as a propulsion mechanism for rotating
the ice pulverizing knives 10. Any type of power transmission coupler could be
used, so as to transfer power generated by the tractor or vehicle to the ice
pulverizing device 100 to actuate rotation of the ice pulverizing knives 10.
[0040] In another aspect, the ice pulverizing device 100 may be provided
as a vehicle which include the ice pulverizing knives 10 and the propulsion
mechanism. In that case, the propulsion mechanism is mechanically coupled to
the drive shaft which is inserted in the the socket of the ice pulverizing
knives
10. The vehicle is further provided with an engine for displacing the vehicle
and
therewith the rotating ice pulverizing knives 10 along the ground surface.
[0041] Reference is now made to Figure 10, which is a flowchart
describing the method of operating the present ice pulverizing device. The
method starts with actuating the rotation of the ice pulverizing knives. The
method then continues with lowering the ice pulverizing knives on the layer of
ice. The method then awaits for the ice pulverizing knives to pulverize the
ice
so as to reach the ground surface thereunder. The method continues with
displacing the ice pulverizing knives along the ground. When the area of ice
on
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the ground has been pulverized, rotation of the ice pulverizing knives is
stopped
and the ice pulverizing knives are lifted from the ground.
[0042] Although the
present ice pulverizing knife and device have been
described in the foregoing description by way of illustrative embodiments
thereof, these embodiments can be modified at will, within the scope of the
appended claims.
