Particulate material loading equipment

Loading equipment for particulate material comprising a working deck and angularly displaceable paddles mounted for repeated to and fro movement about pivotal axes along a portion of the working deck to urge the particulate material over the deck, each paddle being seen as a sector of a circle when viewed along the pivotal axis.

This invention relates to particulate material loading equipment and in 
particular, although not exclusively, to broken rock loading equipment 
comprising loading aprons which in use are adapted to be urged into piles 
of broken rock to be loaded. 
It is known for such loading equipment to have gathering arms which 
repeatedly and continuously sweep over portions of the loading apron deck 
in order to urge broken rock on the deck towards a conveyor extending 
rearwardly from the loading apron. Unfortunately the drive mechanism for 
the gathering arms tends to be intricate and involves a high initial cost 
as well as a high level of maintenance. 
An object of the present invention is to provide loading equipment which is 
efficient, robust, relatively inexpensive and simple to operate. 
According to the present invention, particulate material loading equipment 
includes a working deck for receiving particulate material to be loaded 
and at least one driven paddle device for urging particulate material over 
at least a portion of the deck towards a discharge, the driven paddle 
device comprising an angularly displaceable paddle device mounted for 
repeated to and fro movement about a pivotal axis along the portion of the 
deck, and displacing means for angularly displacing the paddle device 
about the pivotal axis, the paddle device having a working face for urging 
the particulate material, the working face extending from adjacent to the 
pivotal axis of the paddle device towards a radially more remote 
peripheral face of the paddle which, in use when the paddle device moves 
in a material urging direction, substantially extends along the full 
length of the path defined by the radially outer portion of the working 
face of the paddle device throughout angular displacement of the paddle 
device. 
Preferably, the paddle device is seen as a sector of a circle looking along 
the pivotal axis. 
Advantageously, the displacing means comprises a drive shaft passing 
through the working deck, the shaft being drivably connected to the paddle 
device. 
Preferably, a chain sprocket is drivably connected to a portion of the 
shaft below the deck, the sprocket being rotated to and fro by the action 
of ram means on a chain drivably engaging the sprocket. 
Advantageously, two similar but opposed paddle devices are mounted on the 
deck. 
Conveniently, both the paddle devices have drive shafts provided with chain 
sprockets drivably engageable by a common chain and the ram means 
comprises two rams attached to the ends of the chain, respectively, for 
urging the paddles in a non-conveying direction and a further ram engaging 
the chain intermediate the two sprockets for urging the paddle devices in 
a conveying direction. 
Conveniently, control means for the ram means are provided such that both 
the paddle devices are actuated simultaneously to urge particulate 
material towards a central discharge. 
Advantageously, the discharge includes conveyor means. 
The control means may control the ram means such that the paddle devices 
are actuated separately. 
The present invention also provides a mining machine including loading 
equipment as defined above.

FIG. 1 shows loading equipment constructed in accordance with the present 
invention mounted on a track mounted mining machine 1 (only parts of the 
outline of which are shown). The loading equipment comprises a downwardly 
inclined loading apron 2 having pivotal supports 4 for attachment to 
leading portions of the mining machine and a hollow working deck assembly, 
the leading margin 8 of which is tapered enabling the apron in use to be 
urged into the bottom of a pile of broken rock to be loaded. The loading 
apron has an upper working deck 10 having a central cut out discharge 11 
accommodating a scraper chain conveyor 12 for conveying broken rock from 
the loading apron rearwardly towards further converyor means (not shown). 
Broken rock falling from the pile onto the working deck is urged towards 
the conveyor 12 by a driven paddle device comprising two similar, but 
opposed, angularly displaceable paddles 13 and 14 mounted for repeated to 
and fro movement about pivotal axes coincident with the axes of two driven 
shafts 15 (only one of which is shown in FIG. 1). Each paddle 13 and 14 is 
generally shaped as a quadrant looking along the pivot axis of the paddle 
and having an upright working face 16 for urging broken rock which extends 
radially from adjacent to the pivotal axis of the paddle towards a 
radially more remote curved peripheral face 18 which substantially extends 
along the full length of the path defined by the radially outer portion of 
the working face 16 throughout the angular displacement of the paddle. The 
peripheral face 18, thereby, prevents broken rock debris being urged in 
the non-conveying direction by the rear surface of the working face 16. 
The upper face of each paddle is closed by a plate or cover 20 shaped as a 
sector of a circle and the rear face is closed by an upright plate 22. A 
toe plate 24 is provided in front of the working face 16, the curved 
peripheral face 18 projecting forward beyond the working face towards the 
leading margin of the toe plate. As seen in FIG. 1, the leading margin of 
the curved peripheral face 18 has cut outs to help guide the paddle into 
the pile of broken rock on the working deck. 
Each paddle 13 or 14 is drivably mounted on a substantially square-section 
uppermost of the associated drive shaft 15, the paddle being retained on 
the shaft by bolts 25 engaged in threaded holes formed in the end of the 
drive shaft. Each drive shaft 15 extends through the working deck 10 and 
is rotatably mounted in bearings (not shown) provided on the deck 
assembly. The lowermost portion of each drive shaft is substantially 
square-sectioned and is drivably engaged by a similarly sectioned bore of 
a chain sprocket 27 or 28. Thus, rotation of the chain sprockets 27, 28 
results in angular displacement of the paddles 13, 14 respectively. The 
chain sprockets 27, 28 are drivably engaged by a common chain 30, movement 
of which is controlled by ram means comprising two single acting rams 32, 
33 secured between the ends of the chain and to brackets 34, 35, 
respectively, fixedly secured to the deck assembly. The ram means also 
comprises a central single acting ram 36 secured between a bracket 37 
fixedly secured to a leading portion of the deck assembly and a slide 
bracket 38 slidably mounted in two parallel guides 40, 41 of a guideway. 
The slide bracket 38 is provided with a curved chain guide or chain 
bollard 42 which engages the chain 30 intermediate the two sprockets 27, 
28 such that in operation as the ram 32 and 33, and 36 are alternatively 
actuated to move the slide bracket 38 to and fro along the guideway the 
two halves of the chain are urged to rotate the sprockets 27, 28. 
Consequently, the paddles are moved to and fro. As the central ram extends 
to move the paddles in the loading direction the two rams 32, 33 
simultaneously act to maintain the chain tension substantially constant 
throughout operation of the central ram. In practice, internal friction in 
the rams may be sufficient to maintain the chain taut. 
FIG. 2 shows the circuit diagram for the loading equipment of FIG. 1. 
Pressure fluid is supplied by a pump 50 to a manually controlled three way 
hydraulic valve 52. In FIG. 2 the valve is shown in its neutral position 
feeding pressure fluid back to tank. The valve 52 can be actuated to feed 
pressure fluid either to the central ram 36 or alternatively to the rams 
32 and 33, the other rams 32 and 33 or 36 simultaneously being connected 
to exhaust. Thus, if the valve 52 is actuated to feed pressure fluid to 
ram 36 the slide member 38 is urged by the ram 36 along the guideway to 
rotate both chain sprockets together with the drive shafts and paddles to 
urge broken rock towards the central discharge. As stated previously, the 
portions of the chain adjacent to the rams 32 and 33 are kept taut due to 
the internal friction of the rams. When the paddles have moved fully in 
the conveying direction the operator actuates the valve 52 to feed 
pressure fluid to the rams 32 and 33 and to connect the ram 36 to exhaust. 
Thus, the rams 32 and 33 move the chain sprockets, drive shafts and 
paddles in the non-conveying direction ready for more broken rock debris 
to fall on the portion of the working deck swept by the paddles. Thus, by 
repeated actuation of the valve 52 the paddles can be continuously moved 
to and fro to urge broken rock debris towards the discharge and, thereby, 
onto the conveyor which conveys the debris rearwards towards the mining 
machine. 
If it is desired to actuate the paddles non-simultaneously associated 
manual valves 55 and 56 are suitably actuated to prevent feed of pressure 
fluid to the rams 32 and 33, respectively. Thus, actuation of the ram 36 
displaces the piston of only one ram 32 or 33. Consequently, it is 
possible to actuate only one paddle or to actuate the two paddles in turn. 
In other embodiments of the invention, the control means is provided with 
sensing means enabling the operation of the loading device to be 
automatic. 
In other embodiments of the invention, the chain drive is dispensed with 
and each of the paddles 14 is driven repeatedly to and fro by the 
associated ram 32 or 33 acting through a lever extending transverse to the 
pivotal axis of the driven shaft 15, respectively, the lever being 
drivably attached to paddle. 
In still other embodiments of the invention more than two paddles are 
provided on the loading equipment and in which case the paddle devices 
provided on each side of the loading equipment are arranged to feed 
material successively from one paddle to the next paddle.