Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to an apparatus which
may be used to spread sand, gravel, and chemicals such
as salt on snow and ice covered paths, sidewalks and other
pedestrian thoroughfares. For convenience of description,
such an apparatus will be referred to as a sand spreader.
Sand spreaders conventionally comprise a hopper
carried by a frame which has two ground wheels on a common
axle adjacent its rear end. A towing bracket is provided
at the front end of the frame so that the spreader can be
towed behind a tractor. Sand is dispensed from the hopper
by a rotary auger which is positioned in the bottom of
the hopper and is driven in rotation from one of the ground
wheels.
In the particular sand spreader disclosed in
Canadian Patent No. 1,011,358 for example the auger is
cor.nected to a drive wheel by means of a chain and sprocket
mechanism and the drive wheel can be slidably moved into
contact with one of the ground wheels so that the auger
will be turned as the sand spreader is towed over the
ground. While this sand spreader works well, the chain
drive mechanism must be cleaned on a regular basis or it
may jam in use, particularly when the sand spreader is
stored outdoors while not in use.
According to the present invention, there is
provided a sand spreader having a frame supported on wheels
for movement over the ground in use. A sand hopper is
mounted on the frame and has an opening at its lower end
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through which sand can be dispensed. A rotary auger ex-
tends about a longitudinal axis and is positioned in the
opening in the hopper for movement perpendicular to the
]ongitudinal axis between an operative posit}on in which
the auger controls the flow of sand from the hop~er in use
and an inoperative position in which the flow of sand from
the hopper is stopped. A driving wheel is coupled to the
auger coaxially therewith and first and second slides
are coupled to the auger at positions spaced along the
longitudinal axis for movement between the operative and
inoperative positions. The driving wheel is arranged to
peripherially engage one of the ground wheels when the
auger is in its operative position, whereby rotation of
that ground wheel as the spreader moves over the ground
in use drives the auger by way of the driving wheel, and
to move clear of the ground wheel when the auger is moved
to its inoperative position. Means are provided for sim-
ultaneously moving the slides between their respective
first positions in which the auger is in its operative
position and their respective second positions in which
the auger is in its inoperative position, the means includ-
ing an over centre linkage adapted to lock the slides in
their respective first positions when the auger is required
to be operative.
An advantage of this form of friction drive is
that is can slip in the event that the auger becomes jammed
due to the pressence of a stone or other foreign material
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in the sand. A conven~ional chain and sprocket drive has
no provision for slip and accordingly, if the auger does
jam, damage to the drive mechanism is almost inevitable.
The invention will be better understood by ref-
S erence to the drawings wherein:
: Fig. 1 is a perspective view from the frontand one side of a sand spreader in accordance with the
invention;
Fig~ 2 is an enlarged partially fragmented per-
spective view from the front and one side of the auger anddrive mechanism shown in Fig. l;
Fig 3 is a perspective view along line 3 of
Fig. 2 of the slide mechanism shown in Figs. 1 and 2;
Fig. 4 is a perspective view along line 4 of
Fig, 2 of the slide mechanism and agitator drive; and
Fig. 5 is a sectional view along line 5-5 of
Fig. 2.
Referring firstly to Fig. 1, the sand spreader
basically comprises a sand hopper 20 mounted on a frame
22 adapted to be towed behind a trailer or the like. Frame
22 has a pair of side members 24 whiGh are of channel shape
in cross-section and each of which includes a straight
portion 25. A pair of transverse members 26 which are
of similar cross-section extend between the ends of the
straight portions 25. At the left hand end of the frame
;n Fig. 1, the side members 24 extend beyond the relevent
transverse member 26, and are inwardly inclined and joined
~a
directly together at their ends to form a triangular
leading end portion of the frame. A pair of vertically
spaced hotizontal plates 28 are provided at the junction
between th~ s~de members 24 and are formed with vertically
aligned holes 20 to receive a link pin of a tractor hitch
(not shown). `~
The frame is supported for movement over the
ground by a pair of main ground wheels 23 (only one of which
is visible Fig. 1). Each wheel 32 is mounted on a fixed
stub axle 34 carried by a reinforced L-shaped bracket
36 welded to the underside of the relevant frame side member
24 adjacent its rear end.
A stand 37 is provided to enable the frame to be
supported in a horizontal disposition when the sand spreader
is not in use. The stand includes a cylindrical sleeve
38 welded to the front transverse member 26 of the frame.
Sleeve 38 is arranged with is axis vertical and is interally
threaded to receive a threaded spindle 40. A foot 42 is
provided at the lower end of the spindle and a handle 44
on the spindle upper end facilitates rotating the threaded
spindle to adjust the vertical extensionof the spindle 40
and hence the height of the front end of the frame 22.
After the spreader has been hitched to a tractor, the
spindle 40 must of course be lifted by an amount sufficient
to ensure that the foot 42 clears the ground.
As can be seen, the hopper 20 is of generally
triangular shape in side view, comprising a pair of parallel,
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Each end of pipe 56 is closed by a disk member
62 having a central aperture to receive a spindle 63 which
extends axially of pipe 56. Two bolts 57 are provided
to secure the pipe 56 to spindle 63 so that the pipe
rotates with the spindle. Both ends of spindle 63 extend
through bearings 65 and project to the outside of the hopper.
Drive means, to be described, engage one of the projecting
ends of the spindle 63 and rotate the auger unidirectionally
in use to deliver sand from the hopper 20. The provision
on the auger of opposite handed helical blades ~formed
by the rods 53, 60) has the result that sand tends to be
conveyed inwardly from the ends of the auger towards its
centre to distribute the sand. Further, it avoids the need
for a thrust bearing at one end of the auger spindle.
The drive for the auger is taken from the main
ground wheel 32 shown in Fig. 1 to the auger by way of a
driving wheel 66 mounted on the projecting end of the
spindle 63. For convenience of illustration af Fig. 1,
the driving wheel 66 is shown in ghost outline. In prac-
tice each of these wheels carries a pheumatic rubber tire
as indicated in Fig. 3. The drivingwheel 66 is mounted
on one of the projecting ends of the spindle 63. The
spindle 63 is carried by slide mechanisms which are gen-
erally designated 70, 70-1 and which will be more specific-
ally described later. At this stage it is sufficientto say that the slide mechanisms are moveable horizontally
in the direction o arrow 72 in Fig.3 to mo~2e the wheel
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66 between an "on" position in which the wheel 66 is in
peripheral driving contact with the ground wheel 32 and an
"off" in which wheel 66 is clear of wheel 32.
When the driving wheel 66 is in its right hand
position in Fig. 1 (its "on" position), therefore, auger
54 will be driven in rotation by way of the spindle 63.
However, when wheel 66 is in its left hand position in
Fig. 1 (its "off" position) out of peripheral engagement
with wheel 32, the drive will be disengaged and auger 54
will be stationary.
As shown in Fig. 4 the projecting end of spindle
63 opposite the end of spindle 63 on which the driving
wheel 66 is mounted is also carried on a slide mechanism
which is generally designated 70-1 and which will be more
specifically described later. At this stage it is suff-
icient to say that the slide mechanism is moveable hori-
zontally in the direction of arrow 72 in conjunction with
the slide mechanism carrying the driving wheel 66. The end
of the spindle 63 opposite the end carrying the drive wheel
66 carries an elliptical cam 80 arranged to drive an agi-
tator mechanism generally designated 81. This mechanism
comprises a shaft 82 which extends parallel to the spindle
63 of auger 54, and which is shown both in broken outline
inside the hopper 20 in Fig. 1 and in full outline in the
hoppex in Fig. 2, above auger 54. Shaft 82 has welded
thereto a number of longitudially spaced rectangular pro-
jections 84 arranged in two groups, the projections in
i~s~e
the respective groups being posit.ioned at right angles
to one another. As can be seen, in this particular em-
bodiment, there are three vertical projections 84 and
two horizontal projections 84. Shaft 82 extends through
the hopper, its opposite ends projecting through the
respective side plates 46. The end of the shaft 82 ad-
jacent cam 80 is provided with two rectangular projections
86 positioned at right angles to one another such that the
rectangular projections 86 roll on the edge of cam 80~
The length of the rectangular arms 86 and the sides of the
cam 80 are such that the cam 80 is in contact with one of
the rectangular projections 86 when the drive mechanism
is engaged.
The elliptical shape of cam 80 causes the uni-
directional rotation of the spindle 63 of auger 54 to
impart to the agitator an oscillatory motion about the
axis of shaft 82. This will tend to agitate and break up
the sand in hopper 20 immediately before the sand reaches
the auger 54. This oscillatory motion of the agitator
is preferred to a rotary motion as is found in conventional
sand spreaders, as rotary agitators tend to perform a
mixing action which, if the sand is wet, can lead to the
formation of mortar in the bottom of the hopper.
The construction of the slide mechanisms 70,
70-1 which carr~l the projecting ends of the spindle 63
referred to above will now be described in more detail:-
The mechanisms comprise horizontally moveable
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slides 96, 96~1 which are ~eceived in ~uides 98~ 98-1 one
of which is welded to the top sur~ace o~ the straight port-
ion 25 and the other of which is welded to the bottom sur-
face of the straight portion 25. Slides 96, g6-1 ~arry the
projecting ends of the spindle 63 which project through the
oval shaped cut outs 27, 27-1 of the straight portions 25.
~ovement of slides 96, 96-1 is controlled by a cranked oper-
ating lever 102 which is pivotally connected to the straight
portions 25 by a pivot rod 104. Generally elliptical pro-
jections lOQ, 100-1 are provided on each end of the pivot rod
104~ Slides 96, 96-1 are connected to the elliptical pro-
jections 100, 100-1 by means of threaded lug assemblies
106, 106-1 and L-shaped intermediate links 108, 108-1.
Threaded lug assemblies 106, 106`1 consist of flat portions
106a, 106a-1 pivotally connected to slides 96, 96-1 and
threaded portions 106b~ 106b-1 welded to the flat portions
106a, 106a-1 at the end opposite the pivotal connection.
L-shaped intermediate links 108, 108-1 consist of flat
portions 108a, 108a-1 pivotally connected to elliptical pro~
jections 100, 100-1 and projecting portions 108b, 108b-1
which contain threaded openings 108c, 108c-1 adapted to re-
ceive the threaded portions 106b, 106b-1 of lug assemblies
106, 106-1 me arrangement of the threaded lug assemblies 106, 106-1
and the intermediate links 108, 108-1 is such that the distance between
the pivotal connections to the ell~;`ptical projections 100, 100-1 and the
slides 96, 96-1 can be adjusted to prevent jamming of the slide
mechanisms 70, 70-1 in use.
Lever 102 is moveable about its pivot bet~een t~e -
"off" position in which it is shown in Fig. 1 and the "on"
which it is shown in Fig. 3. In the "off" position,
slides 96, 96-1 are drawn to the left in Fig. 1 by the
intermediate links 108, 108-1 and the threaded lug ass-
emblies 106, 106-1. If lever 102 is moved to the left in
Fig. 1 about its pivotl it will cause the rectangular
projections 100, 100-1 to pivot ahout the axis of the
pivot rod 104 thus causing the slides 96, 96-1 to move to
the right and causing the intermediate links 108, 108-1
to go over centre and lock the slides 96, 96-1 in the right
hand position in which driving wheel 66 is in peripheral
engagement with ground wheel 32. This over centered lock-
ing action occurs because the pivot point between the
intermediate links 108, 108-1 and rectangular projections
100, 100-1 is above the line joining pivot rod 104 and the
pivotal connection of the threaded lug assemblies 106,
106-1 to slides 96, 96-1.
As has already been mentioned, the sand spreader
shown in the drawings is intended to be towed behind a
tractor or the like. To enable the tractor driver to op-
erate the slide mechanisms 70, 70-1 from his driving seat,
the other end of lever 102 has an aperture through which
is threaded a rope 110 formed with a knot (not shown)
to prevent it slipping through the aperture. From lever
102, the rope 110 extends rearwardly of the frame and
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around a pulley 112 rotatably mounted on the hopper side
plate 46 which carries mechanisms 70, 70-1. Pulley 112
is secured to the hopper by a bracket 114 and bolt 116
on which the pulley turns. From pulley 112 the rope again
extends forwardly of the sand spreader through a horizontal
guide sleeve 118 welded to one side plate 46. Both ends
of rope 110 are lead forwardly from the sand spreader to the
tractor by which it is towed and are for example tied to a
convenient part of the tractor so that they are within
easy reach of the driver. However, care mustbe taken
to ensure that there is sufficient slack in the rope to
prevent it being accidentially pulled as the tractor moves
relative to the spreader. Considering the slide mechanisms
70, 70-1 to be in the position in which they are shown in
Fig. 1 (i~e., the "off" position), the tractor driver
pulls on the bottom run of the rope to turn the oper-
ating lever 102 of mechanisms 70, 70-1 in a counter clock-
wise direction, thereby bringing the driving wheel 66 into
engagement with wheel 32 to establish a drive train from
that wheel to the auger 54 and to the agitator. The auger
will then rotate and the agitator oscillate to dispense
sand through the bottom of hopper 20. To stop sand being
dispensed, the tractor driver pulls on the top run of
rope 110 to move lever 102 in the clockwise direction and
thereby disengage wheel 66 from wheel 32.
In order to allow variation in the rate at which
sand is dispensed from the spreader, a rear end plate of
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hopper 20 is provided with a hinged lower portion 48a
(see Fig. 5), the position of which can be adjusted to vary
the width of the gap between its bottom edge and the
auger 54.
As shown in Fig. 5, the lower portion 48a is
welded to a second pivot rod 120 which is shown in end
view and which is pivotally mounted on the straight portions
25 of frame 22. The position of the flap forming portion
48a of plate 48-2 is controlled by a rod 122 extending
from the pivot rod 104 to a channel member 123 welded to
the flap portion 48a below the second pivot rod 120.
Rod 122 is screw threaded adjacent its upper end, the screw
threaded portion passing through a nut 124 which is pivot-
ally mounted on a rectangular projection 126 welded to the
pivot rod 104. At its upper end, rod 122 has a handle
130 which facilitates rotating the rod 122 to vary the dis-
tance between the nut 124 and the channel member 123.
The lower end of rod 122 passes through an aper-
ture formed in a bracket 132 which is welded to the lower
portion of channel member 123 as shown in Fig. 5. The
bottom end of rod 122 is provided, above the bracket 132,
with a washer 134 which abuts the front face of bracket
132. A compression spring 136 maintains bracket 132 in
contact with washer 134, the spring extending between the
bracket and a second washer 138 welded to the rod.
It will be appreciated that, by turning rod 122
by means of handle 130, the gap between the flap forming
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portion 48a of plate 48-2 and the auger can be increased
or decreased depending on the direction in which the rod
is turned. It will further be appreciated that the conn-
ection between rod 122 and portion 48a is such that the
latter can hinge outwardly against the action of spring
136 (see Fig. 5), in the event that a stone or other
obstruction is presnt in the sand being dispensed by auger
54.
It will further be appreciated that the position
of the handle 130 is such that the driver sitting on the
seat of the tractor towing the sand spreader can easily
adjust the rate at which sand is dispensed from the spread-
- er. This, in conjunction with the rope arrangement for
engaging and disengaging the driving wh~el 66, greatly
increases the efficiency of the sand spreading operation.
It will further be appreciated that the provision
of the rectangular projection 126 and the pivotal conn-
ection to nut 124 causes the flap forming portion 48a of
plate 48-2 to remain in a spaced relation with the auger
54 as the auger and the slide mechanisms70, 70-1 slide hor-
izontally from the "on" position to the "off" position.
Thus, it can be appreciated that the rod 122 does not have
to be turned during the steps of engagement and disengage-
ment of the drive wheel 66 from the running wheel 32.
When the sand spreader is to be used, hopper
20 is filled with sand to an appropriate level and, ~ith
the spreader hitched to a tractor as described above, is
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towed, for example, along the sidewalk. When the tractor
driver wishes to dispense sand, he pulls on the lower run
of rope 110 to bring driving wheel 66 into contact with
running wheel 32 so that the auger 54 and agitator rod
82 commence operation. Accordingly, sand is dispensed
from hopper 54 across the whole length of auger 54, the
sand being distributed inwardly by the auger as described
above. If it appears that the quantity of sand being
dispensed is incorrect, the rate of sand flow can be ad-
justed by the driver during operation by turning rod 122by means of handle 130 (Fig. 5) to vary the gap at the
deilvery side of the hopper. When the driver has finished
- his sanding run, he simply pulls on the upper run of rope
110 to return mechanisms 70, 70-1 to their inoperative
positions with wheel 66 clear of wheel 32 and the delivery
of sand will cease as the auger 54 comes to rest.
While one specific embodiment of the invention
has been described, it will be obvious that other em-
bodiments falling within the scope of the invention dis-
closed can be utilized. For example, it would be possibleto mount the slide mechanisms on the side of the hopper
rather than on the frame. Accordingly, the invention
should not be limited to the specific embodiment dis-
closed.
