ENGINES FOR THE EXTRACTION OF THE PRODUCE OF MINES, AND NEW ARRANGEMENT OF THE ROPES FOR SUPPRESSING ALL DEAD WEIGHT
Year: 1861

page_text: COMPLETE SPECIFICATION filed by the said Théodore Lemielle at the
Office of the Commissioners of Patonts, with his Petition and Decla-
ration, on the 1st February 1861, pursuant to the 9th Section of the
Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THÉODORE
LEMIELLE, of Bruxelles, in the Kingdom of Belgium, and of 51, High
Holborn, in the County of Middlesex, Civil Engineer, send greeting.
WHEREAS I am in possession of an Invention for "ENGINES FOR THE
EXTRACTION OF THE PRODUCE OF MINES, AND NEW ARRANGEMENT OF THE ROPES FOR
SUPPRESSING ALL DEAD WEIGHT," and have petitioned Her Majesty to grant unto
me, my executors, administrators, and assigns, Her Royal Letters Patent for
the same, and have made solemn Declaration that I am the true and first
Inventor thereof.
NOW KNOW YE, that I, the said Théodore Lemielle, do hereby declare that
the following Complete Specification, under my hand and seal, fully describes
and ascertains the nature of the said Invention, and in what manner the same
is to be performed in and by the following statement and accompanying
Drawings (that is to say):-
In the system at present in use for the extraction of the produce of mines,
the rope to which is suspended the corbs to be raised, after first passing over
a pulley, is coiled up round a roller, on which it turns a considerable number
of times, thus increasing by its own thickness at every turn the radius of the
first coil. The great objection to this system is, that while one of the ropes
is entirely unrolled the other is entirely rolled up, and that their weight,

page_text: which is enormous, is never balanced. When a corbs filled with the produce
of the mine is to be raised the engine must necessarily have sufficient power
to raise, in addition to the cor, the whole length of the rope unrolled in the
shaft. By this process the first coil round the roller is formed by very short
turns, which by suddenly breaking the fibres of the rope, injures it consider-
ably, and renders it less durable.
At the beginning of the ascent the engine has often great difficulty to raise
the load; towards the end of the ascent the contrary defect is made manifest.
The rope which descends on the other side of the shaft tends to draw up the
ascending corbs too rapidly, and may, if the brake be not applied, carry it
above the sheave.
The idea occurred to me of balancing the two ropes by means of each
other, whatever might be the respective positions of the two corbs, and I
have succeeded in effecting this by an arrangement so simple that every one
must feel surprised at its not having always been put into practice in prefer-
ence to all others. The rope is no longer rolled up in a coil, but simply
makes half a turn round a pulley of large diameter placed vertically above the
shaft, and falls on either side of the pulley into the shaft. The two ends are
joined together below the last fastening, forming thus an endless rope, the
lower part of which is guided by a second roller or pulley, round which it also
makes half a turn. The motion is no longer communicated to the rope, but
to the upper pulley, which for this reason I call the moving pulley, and it is
this pulley which draws the rope in its rotatory motion in virtue of the
adhesion of the two surfaces. This adhesion is produced by the weight of the
rope and the two corbs, and is much more than sufficient to communicate
the motion from the pulley to the rope, a fact of which I have become con-
vinced after accurate and repeated experiments. These experiments show
that the net weight that can be raised by the rope on one side varies in pro-
portion to the weight producing the adhesion, that is, to the weight of the
rope added to that of the corbs even when working on pulleys with smooth
surfaces, the net weight that may be raised is equal to of the weight of the
rope, if the rope used be round, and neither tarred nor wet, 12 times this
weight if the rope be tarred, and 14 times if the rope be tarred and wet.
With flat ropes of 2 centimétres by 12, the dimensions generally used in
mines, the above number is increased by 3 (we mean here, of course, the
weight of one side of the endless rope.) Thus, in all conditions of mining
work, the adhesion will be much more than sufficient to raise the net weight,
that is, the weight of the produce to be extracted. If it were necessary,
however, nothing could be more simple than to increase this adhesion either

page_text: by the pressure of a roller, by additional weight, or by a combination of sup-
plementary pulleys; but I repeat that all this is superfluous, and the weight of
the ropes which hitherto has been a source of great embarrassment, becomes,
in my system, a power which renders great service, and is admirably adapted
to the requirements of extraction. Any kind of steam engine may be employed
for the purpose of turning the moving pulley.
In all new installations the simplest engine to be employed may consist of
two vertical cylinders placed on either side of the axis of the shaft, having
their cranks at right angles to each other, in order to avoid the dead points.
The pulley to which the motion is communicated turns in a plane parallel to
that of the ropes. For pits in active operation the engine already in use
can be made available; for this system, which consists in not coiling up the
ropes, may be applied to it in a very simple manner. It is sufficient for the
rope to make half a turn round a pulley placed in the middle of the rollers
now used, and to carry the two ends over the two sheaves in order to join
them at the bottom of the shaft. In no case are toothed wheels ever required
to communicate the motion to the ropes; it is sufficient to give to the moving
pulley a diameter equal to the mean diameter of the roller now employed,
increased by the thickness of the coil. A trifling expence and a suspension
of operations for three or four days would be sufficient for this alteration to be
effected.
The endless rope must pass quite through the corbs by means of a sheath.
The corbs are attached to the ropes by chains of a few yards in length, the
utility of which is as follows:-When the corbs at the bottom of the shaft is
resting on its supports, it must not be supposed that the corbs at the top will
be also at rest. The motion must be continued, the chains of the corbs at
the bottom will slacken and bend while the rope continues its motion, and
the corbs at the top will rise to the level of its supports, on which it will
then rest. If it be desirable to receive the corbs at the top before placing
the one at the bottom on its supports, the motion of the rope is not stopped
until they have both passed beyond their resting places, and being then
reversed, the first corbs is lowered on its supports at the bottom on which it
is stopped, in order to be loaded with the produce of the mine. The chains
are fastened to the central rope by means of iron jaws with bolts on both
sides.
When it is required to extract water from the mine, as it is generally in a
part of the pit below the lower fastening, it is necessary to attach the corbs to
the ropes at a point on a level with the surface of the water, so that they
may be sunk into it according to custom. It is evident that a chain may be
"

page_text: substituted for any part of the rope that is required to be
in the water, provided its weight be equal, length for length, to that of the rope
it replaces.
In order to prevent the corbs from rising up to the sheave, a stop made so as
to slide on the moving pulley may be fixed at the required point on the rope;
the pulley will then turn without drawing the rope with it, thus rendering any
accident impossible. The same effect would be produced of the corbs became
entangled in the ropes, thus preventing them from being broken.
The brake is adapted so as to act only on the moving pulley, embracing at
the same time the pulley and the rope, by which means the motion is stopped
without the slightest shock.
ADVANTAGES OF THIS ARRANGEMENT.
i
1. By this system there is not a single pound of dead weight to be raised;
the rope is balanced throughout. If the extraction is carried on at a
depth of 400 metrés with a cable weighing 6 kilog. per metre, and the weight
of the coal extracted be 2000 kilog. each time, instead of having to raise, at
the beginning of the ascent, as it is the case in the system at present in use, a
weight of 4400 kilog., of which 2400 kilog. of rope or dead weight, only
2000 kilog. net weight is required to be raised, consequently if a new engine
be used with this system, one of half the power only will produce the same
effect, and if the old one. be retained, its useful power will be more than
double, thus either extracting twice the usual quantity at each time, or the
usual quantity with twice the usual rapidity. People were frightened, and not
without reason, at the enormous dimensions it was requisite to give the
engines used for the purpose of extraction in order to meet demands; I
diminish them by one half to produce the same effect.
2. Instead of 800 metrés of sound rope only 400 will be required; the
second 400 metrés, which extends from the bottom of one corbs to the bottom
of the other, acts only by its own weight, and never as a tractive power.
Thus old ropes, which are never wanting in mining establishments, may be
made available.
3. The engine always works with a regular uniform motion; no additional
effort is required to move the load, nor is any resistance necessary when it
reaches the top of the shaft. There is no longer any risk of the corbs being
drawn up to the sheave, nay, it is quite impossible for this to occur even if
the conductor wished it..
4. The engine may be erected as near to, or as far from the shaft as may
be desired; hence those immense foundations, buildings, and roofings so

page_text: ruinous, yet necessary for the enormous engines required to meet the demands
for produce may be dispensed with.
I shall no longer expatiate on the immense advantages of this Invention ;
it consists, not in the adoption of a new engine for the purposes of extraction.
but a new and more simple arrangement of the ropes. Hitherto no one had
supposed that the adhesion of the rope and pulley would be sufficient for
motion to be communicated from one to the other. Having convinced myself
of this fact, the idea immediately occurred to me of giving but one half turn
to the rope round the pulley, and all persons who have witnessed the diffi-
culties attending the working of the engines at present in use for the purpose
of extraction will appreciate at its full value the arrangement which I here
submit to them, and I trust they will not hesitate to adopt it, since it can be
perfectly well applied to pits already furnished with their engines either by
diminishing by one half the effort to be produced, or by doubling their power,
and in all cases the expense of the ropes will be reduced to one-half.
Another advantage for the economy of labour, in connection with the lower
pulley, is, that one half of the force of the extracting engine can be used to
drag the small wagons in the subterranean roads and galeries. The motion is
communicated from the lower pulley through a windlass to the rope connected
with the wagons.
When the pulley is lower than the level of the water it is enclosed in an
envelope, which preserves it from the contact of the liquid, and which is pro-
longed by two pipes preserving equally the lowest part of the rope.
The same object is attained by using a bucket suspended under the corb;
that bucket comes down to draw the water under the level of the pulley, and
exhausts it without interrupting the work of extraction.
In witness whereof, I, the said Théodore Lemielle, have hereunto set my
hand and seal, this First day of February, in the year of our Lord
One thousand eight hundred and sixty-one.
THEODORE LEMIELE
THEODORE LEMIELLE
(1.0.)