Materials handling system

A materials handling system (30) for controlling the gravity discharge of material through a discharge opening (33) onto a conveyor (34) comprises a gate (40) extending across the discharge opening (33) and having a plurality of outlet openings (40.4) therein for the through flow of material from the discharge opening (33) through the gate (40). The gate (40) has closure members (71) for the outlet openings (40.4). First and second linkage members (71.4, 71.5) extend along the gate (40) and a power source (71.6, 71.7) for moving the linkage members (71.4, 71.5) relative to the gate (40) and independently of each other, is provided. Coupling members (71.8) for selectively coupling the closure members (71) to either one or the other of the linkage members (71.4, 71.5) is provided. In an another embodiment, a feeder deck (60) is provided below the gate (40). The feeder deck (60) has a materials receiving surface (61.5), corresponding with each outlet opening (40.4) in the gate (40). A scraper (61.8) for each materials receiving surface (61.5) is provided for moving material along the surface (61.5) to discharge the material onto the conveyor (34).

FIELD OF THE INVENTION 
This invention relates to a materials handling system. In particular, it 
relates to a system which can be used in conjunction with a tunnel 
conveyor for the discharge of bulk materials stored in in-line storage 
hoppers or in open stockpiles. 
BACKGROUND OF THE INVENTION 
Storage hoppers are provided with gates for the discharge of material 
therefrom, normally onto a conveyor belt located below the hopper. In a 
typical installation, a plurality of in-line hoppers are provided with a 
conveyor belt running along a tunnel beneath the hoppers. Such a tunnel 
conveyor then transports the material discharged from the hoppers to a 
desired location. 
Most gates are installed in hoppers by using hog backs in order to narrow 
the opening to a controllable size, typically 4 ft.times.4 ft. These are 
fixed gates which are opened and closed manually to permit material 
discharge onto the belt conveyor. Hang up of material is very common and 
vibrators must be used to relieve plugged materials. 
The gates do not permit accurate metering or control of discharge rates. 
This results in material surges and flooding of the conveyor belts and 
considerable dust emission. 
It is accordingly an object of the present invention to alleviate the 
above-mentioned difficulties. 
SUMMARY OF THE INVENTION 
According to the invention there is provided a materials handling system 
for controlling the gravity discharge of material through a discharge 
opening onto a conveyor, which discharge opening has a width dimension and 
a length dimension in the horizontal direction, the system comprising: a 
gate extending across said discharge opening and having a plurality of 
outlet openings therein for the through flow of material from the 
discharge opening through the gate and including closure members for said 
outlet openings; first and second linkage members extending along said 
gate and a power source for moving the linkage members relative to the 
gate and independently of each other; and coupling means for selectively 
coupling the closure members to either one or the other of said linkage 
members. 
Also according to the invention there is provided a materials handling 
system for controlling the gravity discharge of material through a 
discharge opening onto a conveyor, which discharge opening has a width 
dimension and a length dimension in the horizontal direction, the system 
comprising a gate extending across said discharge opening and having a 
plurality of outlet openings therein for the through flow of material from 
the discharge opening through the gate and including closure members for 
said outlet openings; a feeder deck below the gate having a materials 
receiving surface corresponding with each outlet opening; and a scraper 
for each materials receiving surface for moving material along the surface 
to discharge the material onto said conveyor. 
Further objects and advantages of the invention will become apparent from 
the description of a preferred embodiment of the invention below.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
With reference to FIGS. 1 to 4 of the drawings, reference numeral 30 
generally indicates a material handling system according to the invention. 
The system 30 can be used in conjunction with a plurality of in-line 
storage hoppers (only one hopper 32 being shown in FIGS. 3 and 4) and 
beneath which hoppers 32 a tunnel conveyor belt 34 extends for conveying 
the material discharged from the hoppers 32. Each hopper 32 has a 
discharge opening 33 at its lower end. The hoppers 32 are supported on 
columns 36 or other convenient structures. 
In one embodiment, the system 30 comprises a gate 40 for each storage 
hopper 32 and a feeder deck 60 which is located below the gates 40 and 
with the ability to travel from one gate 40 to another along a rail 42 
which extends along the bottom of the hoppers 32. 
As shown in FIGS. 5A and B, each gate 40 comprises an elongate framework 
40.1 which is supported below its respective hopper 32 on the track 42. 
The framework 40.1 is provided with transverse and longitudinal stiffening 
members 40.2 and a number of pairs of transverse members 40.3 defining a 
series of gate openings or slots 40.4 therebetween. In the present example 
there are four slots 40.4 in the gate 40. Plates 40.5 are provided on the 
framework 40.1 to cover the framework 40.1 leaving only the gate openings 
40.4 unobscured. The gate 40 has a plurality of wheels 40.6 for running 
along the track 42. 
The gate 40 is movable in its longitudinal direction relative to the hopper 
discharge opening 33. In this way, the location of the gate openings 40.4 
can be moved along the hopper discharge opening 33 to counteract hang up 
of material in the hopper 32, as will be described below. The movement of 
the gate 40 in either direction is effected through a pair of hydraulic 
cylinders 40.7 located on opposite sides of the gate 40. The cylinders 
40.7 are connected to the columns 36 at their one end and to the gate 40, 
at their other end, through stiffeners 40.8. Material is prevented from 
flowing between the hopper outlet 33 and the gate 40 by seals 40.9 
provided around the hopper outlet opening 33, as shown in FIGS. 3 and 4. 
A closure plate assembly 70, as shown in FIGS. 7A and B, is provided for 
each gate 40. The assembly 70 comprises a plurality of closure plate units 
71, one for each of the slots 40.4 in the gate 40. 
The units 71 are in association with two pairs of linkage bars, an inner 
pair being referenced 71.5 and an outer pair being referenced 71.4. The 
units 71 are provided with guides 71.10 through which the bars 71.5, 71.4 
extend so that the bars 71.5, 71.4 can be moved relative to the units 71 
by sliding movement in the guides 71.10. Bolts 71.8 which extend into the 
guides 71.10 are provided so that each unit 71 can be selectively fastened 
to either one of the two pairs of linkage bars 71.5, 71.4. 
A pair of opposing hydraulic cylinders 71.7 and 71.6, which are operative 
between the gate framework 40.1 and the pairs of linkage bars 71.5 and 
71.4, respectively, are provided. Thus, the cylinder 71.7 operates to move 
the inner pair 71.5 longitudinally of the gate 40 and the cylinder 71.6 
operates to move the outer pair of bars 71.4. 
As shown in FIGS. 6A, B and C, each of the closure plate units 71 comprises 
a cover plate 71.1 located on a framework 71.2. The framework 71.2 is 
supported by cam followers or rollers 71.3 which travel along a track 
61.23 provided along the opposite inner sides of the gate framework 40.1. 
Sealing strips 71.9 are provided on the cover plate 71.1 to counteract the 
flow of material through the respective slot 40.4 when the cover plate 71 
is closed. 
Each closure plate unit 71 is provided with a U-shaped retainer plate 41.3, 
which is attached to the unit 71, and a retainer plate 41.1, which is 
attached to the underside of the gate 40. 
As shown in FIGS. 8A and B, the arrangement is such that the opening, 
indicated by reference numeral 50, provided by the closure unit 71, when 
in a fully or partially open position under the corresponding gate opening 
40.4, is surrounded by the plates 41.1 and 41.3. As can be seen, these 
plates form a rectangular framework or box around the opening 50. (The 
closure plate unit 71 shown in FIGS. 8A and B has a square shape, whereas 
the embodiment of the unit 71 shown in FIGS. 6A and 7A is of elongate 
shape in plan view). 
As shown in FIGS. 9A and B and 10A and B, the feeder deck 60 comprises an 
outer framework 61.1 which is stiffened internally by perpendicular 
bracing 61.2 and diagonal bracing 61.3. The framework 61.1 is supported by 
wheels 61.4 which also run on the track 42. As can be seen from FIGS. 3 
and 4, the wheels 40.6 of the gate 40 run on an upper part of the track 
42, while the wheels 61.4 run along a lower part of the track 42. 
The deck 60 is provided with a plurality of transverse material receiving 
surfaces or trays 61.5 equal in number with the slots 40.4 in the gate 40. 
The arrangement is such that, when the deck 60 is in position beneath one 
of the gates 40, the trays 61.5 are located beneath the slots 40.4 in the 
gate 40, so as to receive the material falling through the slots 40.4. 
A scraper bar assembly 61 is provided for the feeder deck 60. As shown in 
FIGS llA and B, it comprises a pair of elongate plates 61.6 with 
transverse bracing members 61.7 extending between the plates 61.6. A set 
of three transverse scraper bars or plates 61.8 extending between the 
plates 61.6 are provided for each tray 61.5 and located above the tray 
61.5. As shown in FIG. 9B, the plates 61.6 extend along the length of the 
feeder deck 60 and are slidable relative thereto. 
The plates 61.6 are connected through links 61.13 to cranks 61.12 which are 
located on the opposite ends of a drive shaft 61.11 driven by a drive 
61.10. Rotation of the drive shaft 61.11 results in reciprocating movement 
of the plates 61.6 and hence the scraper plates 61.6 relative to the trays 
61.5. 
The plates 61.6 are supported by cam followers or rollers 61.9 which are 
engaged with and movable along the framework 61.1. 
The shaft 61.11 also drives a pair of sprockets 61.14 and 61.15 which are 
interconnected by a chain 61.16. The sprocket 61.15 in turn drives a shaft 
61.17 on which is located wheels 61.18 and sprockets 61.19. The sprockets 
61.19 are connected to sprockets 61.20 and wheels 61.21 by chains 61.22. 
The driven wheels 61.18 and 61.21 are used to move the feeder deck 60 from 
one gate 40 to another. A clutch mechanism 61.23 is used to engage the 
sprocket 61.15 to the shaft 61.17 to effect the movement of feeder deck 
60. 
Each gate 40 is provided with locking pins 40.10 to lock the gate 40 to the 
deck 60. 
In an alternative embodiment of the invention, the feeder deck 60, instead 
of having only the trays 61.5, is provided with a plate 62.2 adjacent each 
tray, as shown in FIG. 10C, so that the material receiving surface now 
comprises both the tray 61.5 and the plate 62.2. 
Instead of three scraper plates 61.8 for each tray 61.5, only one scraper 
plate is provided for each tray 61.5. In this embodiment, when material 
falls onto the plate 62.2, the area above the plate 62.2 is filled with 
material, thus providing a constant cross section of material. Relative 
reciprocating motion of the scraper bar 61.8 to the plate 62.2 will push 
material further down the plate 62.2 until consecutive reciprocating 
motions eventually push the material off the plate 62.2. In this way, an 
even flow or fall off of material is achieved which can be controlled. 
This arrangement provides a stone box which is capable of reciprocating 
movement. 
In another embodiment of the invention, shown in FIGS. 9C and D, the 
scraper plate 61.8 is replaced by a U-shaped plate 63.1 which is attached 
between the elongate plates 61.6, as shown more clearly in FIG. 12. In 
addition, a bar 63.3 is attached to the elongate framework 61.1, extending 
transversely thereto, as shown in FIG. 13. A scraper plate 63.2 is 
provided on the bar 63.3. 
In operation, the U-shaped plate 63.1, which is attached to the 
reciprocating plates 61.6, will effect reciprocating movement relative to 
the plate 63.2. Therefore, material which falls through the slot 40.4 past 
the open closure plate unit 71 onto the U-shaped plate 63.1 will be moved 
along the plate 63.1 by the scraper plate 63.2, until the material is 
eventually pushed off the plate 63.1. Thus, again, a constant 
cross-section of material being moved along the plate 63.1 can be 
obtained. 
Material which is stored in a hopper 32 is kept inside the hopper 32 by the 
gate 40 with the closure plate units 71 in a closed position, thus sealing 
off the openings 40.4 in the gate 40. 
When material from a hopper 32 is to be discharged, the feeder deck 60 is 
moved to the hopper 32. This is achieved by activating the driven wheels 
61.18 and 61.21 on the deck 60 by the drive 61.10. When the deck 60 is in 
position, the feeder deck trays 61.5 are located below the hopper gate 
openings 40.4. The deck 60 is then locked to the gate 40 by means of the 
locking pins 40.10. 
The flow of material from the hopper 32 is controlled by the gate 40. The 
closure plate units 71 are opened by the linkage bars 71.4 and 71.5 
connected to the cylinders 71.6 and 71.7. The two sets of linkage bars 
71.4 and 71.5 allow for a variation of open slots 40.4, e.g. alternative 
slots 40.4 open with the others closed; or alternate slots 40.4 half open 
and the others fully open; or only one slot 40.4 open and the others 
closed; etc. 
With a particular closure plate unit 71 in an open position, the material 
is discharged through the respective slot 40.4 onto the respective feeder 
deck tray 61.5. The translational motion of the scraper bars 61.8 plows or 
pushes the material off the deck tray 61.5. The rate of discharge of 
material through the gate 40 can be controlled or metered by controlling 
the speed of the drive 61.10. 
In the event that material discharged from the hopper 32 seizes or slows 
due to hang ups, the gate 40 is moved relative to the discharge opening 33 
by means of the hydraulic cylinders 40.7. The gate 40 and the feeder deck 
60 are then moved together due to the locking pins 40.10 which are 
operative for locking the gate 40 and the deck 60 together. At the end of 
the discharge, the gate 40 is moved relative to the discharge opening 33 
until material is entirely discharged. This is achieved by means of a 
scraper bar 32.1 on the hopper which scrapes the material off the plates 
40.5 on the top of the gate 40. 
After the material has been discharged from the hopper 32, the pins 40.10 
are disengaged to release the feeder deck 60 from the gate 40. The feeder 
deck 60 can then be moved to the next hopper 32 to be discharged. 
In a further alternative embodiment of the invention, the feeder deck 60 
can be dispensed with and replaced by a reciprocating stone box 
configuration on the gate 40 so that the gate 40 now also operates as a 
feeder deck. 
In this arrangement, a stone box plate 41.2 is bolted to the inside pair of 
linkage bars 71.5 so that it extends transversely between the bars 71.5, 
as shown in FIGS. 6D and E. A plate 41.2 is provided for each closure 
plate unit 71. 
Since the plates 41.2 are connected to the linkage bars 71.5, the closure 
plate units 71 are connected to the outer linkage bars 71.4 only. In this 
way, the hydraulic cylinders 71.7 will operate to reciprocate the plates 
41.2 relative to the backs of the U-shaped plates 41.3, which will now act 
as scraper plates to produce the reciprocating stone box effect, while the 
hydraulic cylinder 71.6 will operate to move the closure plate units 71 
relative to the slots 40.4 for controlling the through flow of material. 
The U-shaped plate 41.3 will guide material parallel to the belt 34 below. 
Consecutive reciprocating motions of the plates 41.2 will eventually push 
the material off the plate 41.2. Again, a constant cross-section of 
material is obtained with an even fall off which can be controlled. 
In another alternative embodiment, the plate 41.1 can be dispensed with and 
the back of the U-shaped plate 41.3 which is attached to the closure plate 
unit 71, takes the place of a scraper plate. This arrangement is shown in 
FIG. 14, in which the back portion of the plate 41.3 is referenced 41.7. 
In yet another embodiment the gate 40 may be used on its own without the 
reciprocating stone box configuration. In this embodiment, use is made of 
selective attachment of the closure plate units 71 to either one or the 
other pair of linkage bars 71.4, 71.5. 
The advantage of these embodiments without the separate feeder deck 60 is 
that any one of the in-line hoppers 32 can be discharged as desired 
without the need to move the deck 60 to the hopper 32. It is also possible 
to discharge two or more hoppers 32 at the same time. 
The gates 40 and feeder decks 60 may be provided in modular units for 
attachment to each other to fit different sizes of hopper openings 33. 
Some applications of the system 30 will now be described with reference to 
FIGS. 15-19. Parts which correspond with parts shown in FIGS. 1-14 are 
given the same reference numerals. These applications are described with 
reference to a system which includes a feeder deck 60. 
In FIGS. 15 and 16, a typical application with multiple in-line domes 100 
is shown. As shown in FIG. 16, the lower part of each dome 100 is formed 
into two side by side hoppers 32. The system 30 is installed with respect 
to each of the hoppers 32. Thus, in this application, two of the systems 
30 are located side by side, each provided with a respective tunnel 
conveyor 34. 
In FIG. 15, reference numerals 102 and 104, respectively, indicate a 
tripper conveyor and a telescoping asymmetrical soft loading chute for 
loading materials into domes 100. Reference numeral 106 indicates a 
transfer conveyor for receiving material from tunnel conveyors 34. 
The track 42 of each system 30 runs along the bottom of all the domes 100. 
Thus, by movement of the feeder deck 60 along the track 42 to the gate 40 
of a required dome 100, material discharge from any one of the domes 100 
can be effected as desired. 
In FIGS. 17-19, an application of the system 30 in a self-unloading ship 
110 is shown. The ship 110 has seven separate holds 112, the lower parts 
of which are shaped to form two side-by-side hoppers 32, as shown in FIG. 
19. Thus, there are again two of the systems 30 installed side-by-side. 
As can be seen in FIG. 17, there is one tunnel conveyor 34 on the starboard 
side of the ship 110 and one tunnel conveyor 34 on the port side. There is 
also a transfer conveyor 106 on the starboard side and a transfer conveyor 
106 on the port side. 
The track 42 of each system 30 runs along the length of the ship 110 past 
all the gates 40 of the holds 112. Thus, in this application again 
material from any one of the holds 112 can be discharged and unloaded by 
movement of the feeder deck 60 to the gate 40 or one of the longitudinally 
spaced gates 40 of any one of the holds 112, as desired. 
Reference numeral 108 refers to an incline conveyor which receives material 
from the transfer conveyors 106 for transporting the material to the 
outside for unloading purposes. 
While only preferred embodiments of the invention have been described 
herein detail, the invention is not limited thereby and modifications can 
be made within the scope of the attached claims.