Note: Descriptions are shown in the official language in which they were submitted.
~241927
-2-
This invention is concerned with elevators for
particulate material and particularly although not
exclusively to grain augers.
Due to more efficient farming methods and the
increases in acreage under cultivation, farmers are now
faced with handling substantially larger quantities of
grain during harvesting operations. In addition, it is
essential that the grain is harvested not only at the
peak of its maturity but also as rapidly as possible
under suitable weather conditions to avoid the risk of
weather spoilage.
Increased overhead costs in farming have
necessitated the use of contract labour in many
operations including harvesting and transportation ox
the harvested wheat from a farmer's storage silo to a
rail head, mill silo or the like. Accordingly it is
essential that the duration of grain handling
operations be reduced as much as possible to alleviate
the cost of contract labour.
2~ In most farm situations the harvested grain is
first transferred directly from a header into a
transport vehicle such as a truck. The grain is then
transported to a storage silo located at a suitable
position in the field. In practice, a farm may have a
plurality of small silos (either fixed or
transportable) located at different positions in the
field to reduce travelling time between the header and
A :
lZ41927
, -3-
the silo. Alternatively, the plurality of silos may be
located together at the same site as for many farmers
the cost of a plurality of small silos may be
substantially less than a single large silo of
equivalent volume together with its associated integral
grain handling apparatus.
These smaller silos usually comprise a
cylindrical body having a conical roof and a conical
floor. The silo is elevated on a framework to enable
the hopper of a grain auger to be located below an
outlet port in the conical floor. Larger silos may be
supported on a concrete base with a sunken trough
adjacent an outlet port, the trough acting as a feed
hopper for a feed end of a grain auger.
When loading the silo, a grain auger is
positioned such that its outlet chute is located over
an inlet port in the roof of the silo and the feed
hopper below an outlet port on the transport vehicle.
Unloading of the silo is achieved by
positioning the feed hopper of the auger below the
elevated outlet port of the silo and the outlet chute
above the wall of the transportation vehicle.
It can be seen therefore that the requirements
of a grain auger are manoeuvrability as well as
adjustability in terms of its angle of inclination.
Prior art augers of this kind generally
cbmprise an elongate screw auger located within a
12~
,- -4-
tubular body, drive means located at the outlet end
adjacent a fixed outlet chute arranged at right angles
to the rotational axis of the auger, a wheeled support
frame and means to elevate the outlet end of the auger.
The wheeled frame comprised a transverse axle
with a wheel at each end and for transportation and the
auger sometimes included a removable tow-bar at the
feed end of the auger body. In its lowered position,
the feed end of the auger body rests upon the ground
with the auger body inclined to the ground at about 25
degrees. The centre of gravity of the apparatus is
arranged to be close to the axis of the transverse
wheel axle to enable the auger to be manoeuvred by
hand. However when the auger is elevated, e.g. by a
mechanical or hydraulic jacking means between the frame
and the auger body, the centre of gravity becomes
located intermediate the ground wheels and the feed
end. Accordingly when elevated such prior art augers
are very difficult to manoeuvre.
2~ In order to provide greater feed capacity for
such augers, the overall dimensions have been increased
with a consequent increase in difficulty of use and
manoeuvrability.
Other problems with prior art augers relate to
weed hopper design and the tow-bar to facilitate towing
by a towing vehicle. Many prior art augers include a
removable feed hopper to enable the device to be fed
~L24192~
-- 5
by a stream of grain or the like issuing from an elevated silo
outlet or an outlet chute of a transport vehicle or with the
hopper removed, the feed end of the auger may be inserted
directly into a body of grain. Such hoppers usually comprise a
square mouth opening and are supported only by their attachment
to the auger tube. In consequence, the hopper must be accurately
aligned to avoid wastage and damage to the hopper when in use.
Those augers with a fixed tow-bar are limited by the forward
extension of the tow-bar to certain specific uses, while others
with removable tow-bars, while being less limited, are
inconvenient to use due to the need continually to connect or to
disconnect the tow-bar from the auger tube.
It is an aim of the present invention to overcome or
alleviate the problems of prior art elevators and to provide a
relatively inexpensive, high capacity unit which, in use, is
easier to use.
According to one aspect of the invention, a mobile elevator
i6 provided for particulate material, the elevator comprising in
combination: an elongate conveyor tube having an inlet port and
an outlet port; conveyor means for conveying particulate material
through the tube; motor means for operating the conveyar means;
first and second elevation means independently operable
selectively to incline the conveyor tube relative to a ground
surface; a freestanding wheel support frame for the conveyor
tube, the frame including a transversely-extending axle located
. .
I2419Z7
-- 6 --
generally centrally of the conveyor tube and having a ground-
engaging wheel at each end, the frame further including another
wheel located intermediate the axle and the inlet port; means
selectively to move the center of mass of the conveyor tube
longitudinally of the support frame; and drive means for
selectively independently driving the ground-engaging wheels at
the ends of the axle.
Preferably the elevator also includes manual control means
for the drive means, the manual control means being located
generally centrally of the conveyor tube. The elevator may also
include a retractable towbar pivotally attached at one end
thereof to the conveyor tube and having releasable attachment
means intermediate the ends of the towbar, the releasable
attachment means being connectable to a conveyor guard extending
from one end of the conveyor tube to place the towbar in an
extended position for towing, and disconnectable to enable the
towbar to be pivoted to a retracted position, whereby the towbar
extends along the conveyor tube away from the conveyor guard.
The means for moving the center of mass preferably is
associated with one of the elevation means and comprises an
articulated frame having upper and lower link members. The first
elevation means preferably is connected between the upper and
lower link members. The first and second elevation means
preferably are hydraulic cylinders.
'
,.
lZ4~927
- 7
Preferably the support frame also includes a frame portion
extending between the axle and the conveyor tube, and an arm
pivotally depending from the frame portion; and preferably the
another wheel is a castor wheel secured to the free end of the
arm. The second elevation means preferably extends between the
arm and the frame portion. The conveyor means preferably is an
auger.
The elevator may also include a feed hopper for removable
attachment to the inlet port of the conveyor tube, the feed
10 hopper having a resiliently-deformable upper wall portion around
the mouth opening of the hopper. Preferably, the elevator also
includes a releasable conveyor feed assembly connected to the
inlet port, the releasable conveyor feed assembly comprising a
support frame, a housing connected to the support frame, and
powered axially-aligned screw augers located in the housing for
feeding particulate material towards the inlet port of the
conveyor tube, the screw augers being arranged transversely to
the conveyor tube on opposite sides of the inlet port.
In the accompanying drawings,
FIG. 1 illustrates a mobile grain auger in a substantially
horizontal state;
FIG. 2 illustrates the auger in an inclined state;
FIG. 3 illustrates a retractable tow-bar assembly;
FIG. 4 illustrates a feed hopper assembly;
FIG. 5 illustrates a side view of an alternative feed
hopper;
f
1241927
- 7 a -
FIG. 6 shows a perspective view of the hopper of Figure 5;
FIG. 7 shows a front perspective view of a screw feeder
which may be employed in place of a feed hopper; and
FIG. 8 is a rear perspective view of the screw feeder of
Figure 7.
In FIG. 1, the apparatus includes a support frame 1 having a
transversely-extending axle 24 (FIG. 2) with a ground-engaging
wheel 2 at either end thereof. The rear end 3 of the support
frame 1 is pivotally attached to the conveyor tube 4 which has a
screw auger 5 rotatably mounted within it. The tube 4
,~ 2glg27
--8--
, and the screw auger S form an auger assembly. The
forward end of the auger assembly includes drive means
6 such as a hydraulic motor to operate the auger
screw. The outlet port 7 of the conveyor tube 4
5~ includes a hood 8 which is pivotally mounted to the
tube to direct the stream of grain issuing from outlet
port 7 at a selected angle. The conveyor tube is
reinforced with a truss-like frame 9 having a central
upright frame member 10 located approximately at the
centre of mass of the auger assembly. An articulated
frame comprising an upper link frame 11 and a lower
link frame 12 is pivotally connected between frame
member 10 and the transversely extending axle 24. An
hydraulic cylinder 13 is pivotally connected between
upper link frame 11 and lower link frame 12.
The support frame 1 includes a main frame 14a,
an arm 14 pivotally connected at its upper end to frame
14a and a castor wheel assembly 15. The assembly 15 is
secured to the lower end of arm 14. A further
hydraulic cylinder 16 is pivotally connected between
frame 14a and arm 14. The castor wheel assembly 15
includes means to vary the castor angle by tilting of
pivot pin 16. The housing 17 for pivot pin 16 is
pivotally connected adjacent its base to arm 14 and
includes an apertured bracket (not shown) which may be
pinned in registry with one of a series of apertures on
a bracket associated with arm 14 thereby varying the
- ~24~9Z7
castor angle of pivot pin 16. Alternatively, the
castor angle may be varied by any other suitable
mechanical or hydraulic means.
The rear or feed end of the auger assembly
includes a removable feed hopper 18 and a retractable
tow-bar 19, both of which are desc.ibed in more detail
.later.
The support frame 1 has mounted to it a source
of hydraulic power comprising an engine 20, a fluid
reservoir 21, hydraulic control valves 22 and an
operator's seat 23. Control valves 22 are arranged to
selectively control the auger screw drive 6, the
hydraulic cylinders 13 and 16 as well as the hydraulic
motors associated with ground wheels 2. The apparatus
of FIG. 1 thus comprises a self-propelled screw auger
elevator.
FIG. 3 shows the method of attachment of the
retractable tow-bar 19. One end 29 of tow-bar 19 is
pivotally attached to the conveyor tube 4 by a bolt or
the like 30. A bracket 31 is releasably attached to
boss 27 by a pin or the like 32. To retract the
tow-bar or to fit the hopper 18, pin 32 is removed and
the tow-bar 19 is lowered slightly such that bracket
31 clears boss 27. The tow-bar is then pivoted
rearwardly and bracket 31 is connected to the pin 32 by
a further boss (not shown) on the underside of conveyor
tube 4.
~Z41927
--10--
IG. 4 shows hopper 18 attached to the feed
end of conveyor tube 4 with the tow-bar 19 in its
extended position. The hopper is supported at its
lower rear wall 28 by boss 27 extending therethrough
and also by releasable screw clamp 26 extending around
the conveyor tube 4.
The feed hopper 18 is formed with a
substantially circular mouth and an upper rim 25 of a
resiliently deformable material such as rubber or
plastics. The circular mouth permits the hopper to be
fed from either side or the front. This is considered
to be an advantage over prior art square or rectangular
hoppers designed generally to be fed only from the
front. The resilient rim 25 is able to withstand
accidental minor collisions with silos, transport
trucks and the like without damaging the hopper mouth
as in prior art screw augers. The resilient rim also
enables the hopper to firmly engage against a vertical
surface such as the rear wall of a transport vehicle
adjacent an outlet port therein to reduce spillage.
Figures 5 and 6 show an alternative feed
hopper 40 to that shown in Figure 4. Like parts bear
the same numerals as used in Figure 4. The hopper has
side walls 41, 42 and an end wall 43. Boss 27 extends
through wall 43 and a releasable screw clamp 26
extending around tube 4 secures the hopper to the
tube. The hopper 40 is substantially trapezoidal in
124~927
cross section and has a raised end 44. The hopper is
provided with a rim 45 of resiliently deformable
material such as rubber or plastics. The rim 45 has a
raised portion 46 adjacent end 44. Rivets 47 secure
the rim 45 to walls 41, 42, 43.
Figures 7 and 8 show yet a further alternative
feed mechanism for the screw auger.
The feed mechanism 50, known as a "sweep",
comprises oppositely directed augers 73, 74 which
direct grain or other particulate matter inwardly
towards the feed end of screw auger 5 for feeding up
conveyor tube 4.
The "sweep" 50 comprises a tubular frame
member in the form of a torque table 51, end housings
76, 77. Augers 73, 74 are journalled at their inner
ends in bearings 78, 79 respectively which bearings are
suspended from torque tube 51 by brackets 80. The
augers 73, 74 are journalled at their outer ends in
housings 76, 77 which house a suitable drive mechanism
such as a gear train, chain and sprocket assembly or
belt and pulley for rotation of augers 73, 74. The
augers are powered by a fluid powered motor 70
operatively connected to a rotating shaft contained
within torque tube 51, which shaft is operatively
connected to the drive mechanisms contained within
housings 76, 77. The flights of augers 73, 74 are of
opposite hand and thus augers 73, 74 both rotate in the
1241927
-12-
same direction. By completely housing the drive shaft
and drive mechanisms within the torque tube 51 and
housings 76, 77 the entire drive train is protected
against intrusion of dust and foreign matter such as
grain thereby reducing operational maintenance
requirements.
The sweep 51 has a support collar 52
comprising ring 53 and rods 54. The ends of rods are
apertured and fit through eyes 55 on the tube 4.
Wedges 56 pass through the apertures and releasably
secure the feeder 50 to the tube 4 for rapid attachment
and detachment of the sweep assembly 50. The sweep 51
has two support wheels 60 journalled about an axle 61.
The axle 61 is connected to shroud 57 by bracket 62.
Mounting 63 is adjustably securable to the tube 51 and
for this purpose has a series of apertures 64, a
selected one of which may be used to secure mounting 63
to the tube 51 via bracket 65.
The embodiment of Figures 7 and 8 is
particularly suitable for handling of grain and like
particulate material which is stored as a pile on a
ground surface. The operation of the apparatus
according to the invention will now be described with
reference to FIG. 2. The apparatus is driven to a
suitable location say in the orientation shown in FIG.
1. To facilitate manoeuvrability, the pivot pin 16 of
the castor wheel assembly 15 is placed in an
-` ~241927
-13-
approximately vertical position and steering is
effected by selectively actuating the control valves of
the hydraulic motors associated with each ground
wheel. As the drive to one ground wheel may be
reversed relative to the other, the castored frame -
enables the apparatus to be turned within its own
length. Upon approaching a silo, the outlet end of the
screw auger 5 is elevated by means of hydraulic
cylinder 13. This extends upper and lower link frames
11 and 12 such that the centre of mass of the screw
auger assembly remains substantially over the
transversly extending axle 24 even when the conveyor
tube reaches its maximum angle of inclination. The
outlet port 7 is positioned over silo inlet and the
angle of the pivotal chute 8 is adjusted to direct the
stream of grain accurately into the silo. When
elevating the outlet end of the screw auger asembly,
appropriate adjustment may be made with hydraulic
cylinder 16 either to prevent feed hopper 18 from
contacting the ground or to accurately locate it below
the outlet of a transport vehicle.
To unload a silo into a transport vehicle,
substantially the reverse procedures to that mentioned
above are employed. The apparatus is driven towards
the silo with the feed hopper 18 preceding. The hopper
is located below an outlet port of the silo and by
suitable operation of either or both of cylinders 13
~2~192~ -
-14-
and 16, the outlet port 7 of the auger conveyor
assembly is lowered to a suitable height above the
transport vehicle. As can be seen in FIG. 2, tow-bar
l9 is folded to a retracted position to avoid fouling
with the silo support structure.
To unload an unelevated silo of the type
having a sunken pit or trough adjacent its base, it is
necessary to remove the feed hopper from the end of the
conveyor tube. This is readily accomplished by
releasing screw clamp 26 and sliding the hopper over
the boss 27 extending through a lower wall 28 of the
hopper. The apparatus is then propelled towards the
pit with the feed end of the screw auger being lowered
by means of cylinder 16.
It will be clear from the foregoing
description and attached drawings that the elevator
according to the invention offers a substantial
improvement over prior art elevators of this type.
Possibly the greatest advantage is that a substantially
2 larger, high capacity screw auger is capable of being
operated by a sole operator with a far greater degree
of manoeuvrability than hitherto possible.
A particular advantage of the presentinvention
will be apparent. When prior art grain augers are
fully inclined, the centre of mass of the screw auger
assembly becomes located between the supporting ground
wheels and the feed end of the conveyor tube which
~Z419Z7
-15
normally rests on the ground surface for support.
According great difficulty is encountered in removing
or attaching a removable hopper or tow-bar assembly due
to the weight of the conveyor tube at the feed end.
With the present invention, cylinder 16 is used to
elevate the feed end to permit such removal or
attachment by a single operator.
A number of modifications or variations to the
invention are of course possible. To provide a greater
degree of stability in use, the apparatus may be
provided with an adjustable axle assembly to vary track
width. The main axle tube may include a hollow
sub-axle rotatably journalled at each end and adapted
for connection to a drive means. An axle shaft
connected to a wheel may be slidably located within the
sub-axle to increase or decreas track width. The axle
shaft and sub-axle may be locked together by a grub
screw or the like. In this manner the track width of
the apparatus may be reduced to comply with road
traffic regulations or to fit a rail car for rail
transport. In use, the track width may be inceased to
enhance the stability of the elevator, particularly in
the fully elevated position.
In a further modification, the lower end of
cylinder 13 may be disconnectable from cross bar 12a on
link frame 12 to permit the conveyor tube 4 to rest on
cross bar 12a. A further cross bar (not shown) is
12~927
provided at a lower position on link frame 12 for
connection to the free end of cylinder 13. In this
manner the height of the apparatus may be substantially
reduced for storage, towing or transportation purposes.
When transporting the device over long
distances by towing behind a vehicle, it is possible
that a directly connected hydraulic drive system may
become overheated. To avoid this problem the drive
system may be indirectly connected to road wheels 2 via
a disconnectable drive mechanism i.e. a chain and
sprocket drive. Rather than have the hydraulic motors
directly connected to the wheel hubs the motors may be
attached to the axle tube or frame 1. A chain connects
sprockets on the drive motor and the wheel hub and a
chain tensioner may be provided whereby in the
untensioned state the chain may be removed to allow
free wheeling of road wheels 2. Alternatively the
device may be provided with a removable transportation
assembly comprising a wheeled axle incorporating a
suitable shock absorbing suspension such as a rubber
filled torque tube assembly or the like. In this
manner the removable transportation assembly is
attached to the axle of the device or to frame 1. The
road wheels 2 are removed to permit transportation.
Inyet a further alternative, pivotable free wheeling
transportation sub assemblies may be attached to the
axle or frame. For long distance transportation the
1241927
-17-
pivotal suspension units are lowered and locked into
position to elevate road wheels 2 or road wheels 2 are
simply removed.
To further facilitate road transportation, a
tow-bar assembly may be attached to frame 14 instead of
the auger tube as illustrated in FIG. 1. In this
manner the effective towing length of the assembly is
substantially shortened thus avoiding the need in some
districts for an escort vehicle normally required for
long loads. The tow-bar may be removably attached to
frame 14 whereby castor wheel assembly 15 is elevated
during transportation or alternatively castor wheel
assembly 15 may be removed from a mounting bracket to
enable the tow-bar to be attached thereto in its stead.
It will be clear to a skilled addressee that
many other modifications and variations may be possible
without departing from the spirit and scope of the
invention. For example the screw auger conveyor may be
replaced by a "belt in tube" conveyor of known type
wherein an endless belt passes through the conveyor
tube forming either a trough or a substantially closed
moving hollow cylinder for conveying material through
the conveyor tube.
