Improvements in Apparatus for Rope Haulage in Mines and the like.
Year: 1899

page_text: Date of Application, 2nd Sept., 1899-Accepted, 7th Oot., 1899
COMPLETE SPECIFICATION,
Improvements in Apparatus for Rope Haulage in Mines and the like.
We, SIEMENS BROTHERS & Co. LIMITED, of 12, Queen Anne's Gate, West-
minster, in the County of London, Electrical Engineers, do hereby declare the
nature of this invention (as communicated to us from abroad by Siemens &
Halske Aktien Gesellschaft of Markgrafen Strasse No. 94, Berlin, S.W., Ger-
many, Electrical Engineers) and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement:-
This invention relates to that system of rope haulage for mines and the like
where the hauling rope is not fixed upon the winding drum but the hauling
power is obtained solely by the frictional adhesion of the rope to the drum.
With this system it is usual in order to increase the frictional hauling power as
much as possible to cause the rope to pass successively round two or more rope
drums all of which are driven by the same motor or set of motors. This arrange-
ment has however the disadvantage that in the event of there being the slightest
difference in the diameters of the drums, strains are caused in the parts of the
hauling rope passing from the one drum to the other which might increase to
such an extent as to cause considerable weakening or even fracture. Figs. 1 and 2
of the accompanying drawings shew respectively an elevation and plan of an
arrangement of the above described kind. The rope c coming from one of the lift
cages in the mine shaft, passes first over the rope wheel and after passing round
drun a and then round 6 as many times as may be required, it passes at c¹ back
to the second rope wheel and lift cage of the shaft. The two drums have their
cranks connected by a coupling rod a so as to be driven simultaneously by the
motor engine e
Thus if the diameter of drum a should be only slightly smaller than that of
drum 6, then as both drums are made to perform their revolutions in the samo
time, it follows that the drum b will endeavour to draw the rope forward at a
greater speed than the frictional hold thereof of drum a will allow.
If the frictional contact of the rope with the drum is moderate, this
difference may be compensated for by slip, but if the friction be greater, it will
result in a stretching of the rope between a and b and eventually in the fracture
thereof; under any circumstances the rope will be injuriously affected.
The present invention has for its object to obviate this disadvantage and
it consists in employing three rope drums, each of which is driven by an in-
dependent motor and which are arranged as we will describe with reference to
Figs. 3 to 6 of the drawings. Fig. 3 shews a side view, Fig. 4 a front view,
Fig. 5 a plan and Fig. 6 a perspective view. The rope coming from the rising
cage n in the shaft passes first round the pulley g, then round the pulley i and
then round the pulley h to the descending cage o. Each of the pullies is driven
by an independent motor k, l, m, which in the example shewn are assumed to be
electromotors. With this arrangement, if one of the rope pullies should happen to
be larger in diameter than the others, the motor of that pulley would simply
drive it at a correspondingly lower speed, so as to run with the same surface
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page_text: speed as the others, and consequently no excess of strain would be produced in
the parts of the rope passing from the one pulley to the other.
The above described arrangement in which the pulley is situated inter-
mediately between the pulleys h and 9 possesses the farther advantage that as
the frictional resistance of the rope on pulley i will be double that on the pulleys g
and h, double the power can be applied to effect its rotation without risk of slip
this being indicated by providing it with two electromotors m or it might have
a single motor of double power so that either a greater hauling power can be
applied with the same sized pulleys or the same hauling power can be applied
with smaller sized pullies. The latter arrangement would afford the advantage
when electromotors are employed that these could be run at a higher and there-
fore more favourable speed.
Instead of each of the pulleys having only a single turn of the hauling rope,
as shewn, they might each have two or more turns thereof by providing them
each with a guide pulley for leading the rope from the one groove to the next one.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, we declare that what we
claim is
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In apparatus for rope haulage by frictional adhesion the arrangement of three
pulleys, round which the rope is successively led in such manner that it passes
from the one outside pulley to the middle one and from this to the second outside
pulley, each pulley being driven by an independent motor, substantially as and
for the purpose described.