An Improved Method of and Means for Ventilating and Working Mines.
Year: 1888

page_text: Date of Application, 22nd Sept., 1888
Complete Specification Left, 22nd July, 1889-Accepted. 14th Sept., 1889
PROVISIONAL SPECIFICATION.
An Improved Method of and Means for Ventilating and
Working Mines.
I, CARL MEISSNER of Dudweiler near Saarbrücken, in the German Empire,
Royal Inspector of Mines, do hereby declare the nature of this invention to be as follows:-
This invention relates to a method of and means for carrying on the working of
mines, chiefly coal mines,-and it has for object to do away with dangerous walls,
thirls, or narrows; to diminish the loss of ventilating air; to regulate the supply of
ventilating air to each of the working places so that each of these shall be supplied
with air of the same freshness and in the same quantity, thereby maintaining an
equable temperature in all of them; to render it impossible at the most dangerous
time, namely when a board is being worked, for an explosive mixture of gases to he
formed in overhead boards by the passage thereto of firedamp from the one or more
than one underneath that is or are being worked; to diminish also at the same time
the danger to the upper boards in the event of an explosion taking place in one of the
lower ones; to diminish the overhead pressure from the roofs of the boards upon the
supports and to diminish the cost of the long work homeward, and win an increased
quantity of round or best coal.
For this purpose the horizontal boards are divided in their whole length from their
commencing point at a self acting inclined plane to the further limit of the workings
each into two airtight divisions shut off from one another by an air brattice. The lowest
of the two divisions serves as an intake for the fresh air and the upper one for the
discharge of air and for the extraction of material. Fresh ventilating air is supplied
from below to the self acting inclined plane and thence is distributed into the lower
divisions of the several boards. Each of these smaller air currents passes through its
respective lower division up to the end of the board then passes into the upper or
extraction division of the board back to a heading where it joins the other air currents
forming the previous main air current which flows to an airway-return. Each of the
small air currents is carried across the heading by cross courses. In this way the
boards are not in air communication with one another and consequently fire damp
and explosive gases cannot penetrate from the one into the other. The distribution of
the aggregate ventilating air current into such a number of separate currents as there
are boards and the comparatively large cross sectional area which each of the separate
currents possesses causes a diminution of the atmospheric depression and therewith a
diminution of the loss of ventilating air.. The air is supplied to the boards in the
desired quantity by means of valves or slides.
-
Generally the distribution is so regulated that each working place shall receive
the same quantity of air and therefore be at the same temperature. Doors are
provided where required, for keeping the air currents in the proper path. They may
be double doors so as to prevent disturbance of the ventilation when passing through
them. The self acting inclined plane is shut off at top from the air way by doors and
provided with a bye gallery connecting the air-way so that air may pass and be shut off
from the self acting inclined plane. If there is no working in or over the air-way the
the closure may be built in the self acting inclined plane itself in which case the bye
gallery would be unnecessary. Thus the long work homewards proceeds without
being retarded by the cutting through of the boards and without the usual loss of
coal. The coal falling in the cutting through of the boards is of small value but here
s won at less cost and in better condition. There is less pressure to be taken by the
supports whereby a larger yield of round coal is obtained.
Dated this 22nd day of Sentember 1888.

page_text: COMPLETE SPECIFICATION.
An Improved Method of and Means for Ventilating and
Working Mines.
I, CARL MEISSNER of Dudweiler near Saarbrücken, in the German Empire, Royal
Inspector of Mines, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to a method of and means for carrying on the working of mines
-chiefly coal mines and consists in the method of building board and pillar work, which
is generally constructed with headways or direct communication between the individual
boards so that the ventilating air passes in through the bottom board to its working
place, whence a headway conveys it to the working place directly above and thus it
travels from the working place of one board to the working place of the one above
until it passes out of the return air way after having been in contact with all the
working place at the end of boards.
According to my invention the said headway between boards is entirely done away
with, whereby several important advantages are obtained, among which for the
better understanding of the import and scope of my invention, I may mention, that
there is a saving in cost and in time of building up and that the individual boards
receive an equal quantity of fresh air, so that the temperature is also equalized.
Furthermore the loss of air through leakage is lessened and during the time of
driving of the boards there is no possibility for an explosive mixture of gases to be
formed in overhead boards by, the passage thereto of fire damp from the one or more
than one underneath that is or are being worked. Likewise the occurrence of an
explosion in any one board does not endanger the lives of the workers in other
boards, nor do the blasting-explosive gases which may be produced by a slot in any
one board penetrate into and inolest the workers in other boards. The roof pressure
is also diminished because the pillars are not cut through by headways.
The manner in which I prefer to carry my invention into effect is shewn in the
accompanying drawings.
Fig. 1 is a general plan of board and pillar work according to my invention.
Fig. 2 is a cross section of board on the line -a.
Fig. 3 is a longitudinal section through board on the line y-y.
The boards issuing from the self-acting inclined plane A are divided lengthways
in such a manner, that two channels B & C (Fig. 1 & 2) are formed. The lower
channels B serve the purpose of intake, the upper one that of return air-way and
is also used for hauling purposes. The partition or brattice is of such a construction,
that no intermixture of air can take place. The brattice may be conveniently made
of wood and sail-cloth, which can yield to the roof pressure.
The rubble E which falls in in course of working is let into the lower parts of the
board.
The fresh air enters, as indicated by arrows in Fig. 1, at the bottom of the self-
acting inclined plane A and divides itself into the in-take airways B. being prevented
from access to air-way C by means of double doors 1. Each split-current passes
through the said air-ways B to the working place, whence it doubles back passing
through the air and haulage-way Cinto the travelling-road F, where it meets with
the other split-currents ultimately passing away, through the main return air-road G.
The fresh-air currents passing from the inclined plane A through boards B cross the
travelling road F by means of air crossings H as shewn in Fig. 3.
The individual boards are consequently not in direct communication with each
other so long as the limit of the panel has not been reached.
The subdivision of the main air current into as many split currents. as there are
boards and the proportionally large section which is at the disposal of each
split-current causes depression to become diminished and consequently less loss
of air.

page_text: The proper distribution of air in the individual boards is effected by means of
regulators.
The inclined plane A is shut off above with the doors & and a round about way T
is provided if haulage takes place through the main return road, but if no haulage
must take place through the main return road G the inclined plane is closed by
means of a stopping and in that case the said round about way T is not necessary.
The pillars are most conveniently broken through from above downwards, the
brattice being at the same time extended downwards.
When the pillars are being removed, each pillar receives, in a similar manner as
formerly each board, fresh air direct from the inclined plane, the air passing along
the pillar faces to the main return road G. As soon as the pillars are broken
through and when there is no fear of the pillars falling in, then the brattices are at
once broken down in all the boards up to the travelling way F, which is then closed
with doors above each board. Otherwise and when special reasons do not prevent it,
such as for instance strong roof pressure, then the brattice is broken down only
gradually as the work of removing the pillars proceeds, so that when a pillar breaks,
it may be ventilated in the same way as formerly the board.
In the same manner as when working horizontally placed boards the system of
pillar and board work without headways is also applicable when working gently
ascendant boards as shewn in Fig. 4.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
The method of constructing board and pillar work without headways consisting
essentially in dividing the board longitudinally and causing the air currents to
travel substantially in the manner as & for the purposes described and as shewn in the
drawings.
London July 30th 1989