AN IMPROVED IMPLE- MENT OR APPARATUS TO BE USED IN GETTING OR BREAKING DOWN COAL OR OTHER MINERALS
Year: 1877

page_text: LETTERS PATENT to George William Elliott, of Chowbent, in the County of
Lancaster, Mechanical Engineer, for the Invention of "AN IMPROVED IMPLE-
MENT OR APPARATUS TO BE USED IN GETTING OR BREAKING DOWN COAL OR
OTHER MINERALS."
PROVISIONAL SPECIFICATION left by the said George William Elliott at
the Office of the Commissioners of Patents on the 28th March 1877.
GEORGE WILLIAM ELLIOTT, of Chowbent, in the County of Lancaster, Mechanical
Engineer. "AN IMPROVED IMPLEMENTOR APPARATUS TO BE USED IN GETTING OR
BREAKING DOWN COAL OR OTHER MINERALS."
This Invention relates to an improved implement or apparatus for use in
wedging, winning, or breaking down coal or other minerals.
This object has previously most generally been effected by first drilling or pre-
paring a hole in the mineral, and then placing a wedging implement therein (com-
posed of three pieces, a central wedge and two segments or cheeks made of iron or
steel), and subsequently either driving or withdrawing the wedge between the
segments, so as to force them apart and effect the fracture of the mineral.
This Invention is based on the principle of the propelled wedge, and by its
adoption many great disadvantages attendant on this principle as hitherto applied
are overcome, a principal one of these disadvantages being that when the wedgo
has been driven in far as possible, whereby the maximum amount of expansion is
obtained, and the mineral fails to be fractured or brought down, it is not possible to
insert an additional wedge or in any way increase the expansion, and the implement
has therefore to be left in place until it is either hewn out or the mineral is brought
down by other means.
In my present improved implement I employ two central or driving wedges of
peculiar conformation (as herein-after described), and which rest upon each other
along the longitudinal axis of the implement, their inner faces being coincident,
while their outer faces are inclined and form the wedge planes, upon or against
which the segments or cheeks are placed, one on each side. The four pieces when
thus combined, and in their proper position to commence work, present in cross section
Davina G71
"

page_text: a circular figure corresponding or nearly so in diameter with the circumference of
the drilled hole.
From the point where the inclined planes of the wedges and of the segments
terminate all four pieces are continued outwards by thinner bars, which (when the
implement is placed in position in the hole) project beyond the orifice thereof, the
segments very slightly, and the wedge pieces considerably. Also at the point
where the inclines of the wedges cease the bars which form their continuation,
instead of being coincident and resting upon cach other, as do the inner faces of
the wedges as above alluded to, spring or deviate slightly from the axial line, so
as to leave an opening between them sufficient for introducing an additional wedge
if required.
The improved implement is used as follows:-A hole of the required diameter
and length having been drilled in the mineral, as usually, the segments are placed
therein, a space being left between their inner ends and the same end of the hole
(so that the wedges may have sufficient freedom of action endways), and their bar
ends projecting beyond the orifice of the hole; the wedge pieces are then inserted
between the segments and pushed in as far as can be done by hand; then with a
haminer the wedges are alternately driven in a little at a time until the desired
fracture of the mineral is effected; but if the maximum amount of expansion thus
attainable is not sufficient to fracture the mineral as desired an additional wedge is
then introduced at the opening above referred to, between the wedges, to produce a
sufficient amount of expansion.
The advantages of this system of double wedges are obvious, because the
power of a wedge being in proportion to its tenuity, or the small angle of its
inclined planes, by this system double the expansive force may be obtained to that
obtainable with a single wedge with the same expenditure of propelling on cach
wedge. A considerably increased wedging angle can thus be obtained over that
obtainable with a single wedge; these are material advantages, the object of using
the implements being to obtain the greatest possible expansive force against the
material forming the circumference of the hole with the least expenditure of pro-
pelling power.
According to this system also there is the further advantage of being able to
introduce an additional wedge between the others if necessary, and so increase the
available power considerably.
Another important advantage is, that the implement can be made very
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said George William Elliott in the Great Seal Patent Office on the 28th
September 1877.
GEORGE WILLIAM ELLIOTT, of Chowbent, in the County of Lancaster, Mechanical 4
Engineer. "AN IMPROVED IMPLEMENT OR APPARATUS TO BE USED IN GETTING OR
BREAKING DOWN COAL OR OTHER MINERALS."
This Invention relates to an improved implement or apparatus for use in
wedging, winning, or breaking down coal and other minerals.
This object has previously most generally been effected by first drilling or pre-
paring a hole in the mineral, and then placing therein a wedging implement com-
posed of three pieces, a central wedge and two segments or cheeks (made of iron or
steel), and subsequently either driving or withdrawing the wedge between the
segments, so as to force them apart and effect the fracture of the mineral.
The present Invention is based on the principle of the propelled wedge, and by
its adoption many great disadvantages attendant on this principle as hitherto
applied are overcome, a principal one of these disadvantages being that when the

page_text: wedge has been driven in as far as possible whereby the maximum amount of
expansion is obtained, and the mineral rails to be fractured or brought down, it has
not been possible to insert an additional wedge or in any way increase the expan-
sion, and the implement has therefore had to be left in place until it was either hewn
out or the mineral was brought down by other means.
The improved apparatus forming the subject of the present Invention is illus-
trated in Figures 1 to 13 of the accompanying Drawings.
According to the modification illustrated in Figures 1 to 8 1 employ two central
or driving wedges 1 (of the peculiar conformation herein-after described), which
rest against each other along the longitudinal axis of the implement, their inner
faces 2 being coincident, while their outer faces 3 are inclined and form the wedge
planes, against which the segments or cheeks are placed one on eachside. The four
pieces (1, 1, 4, 4) when thus combined and in their proper position to commence work.
(see Figure 1), present in end view and cross section (see Figures 2 to 7) a circular
figure corresponding or nearly so in diameter with the circumference of the drilled
hole. From the point, 5 where the inclined planes 3, 6, of the wedges 1 and of the
segments 4 terminate, all four piecos (1, 1, 4, 4,) are continued outwards by thinner
bars 7, 8, which when the implement is placed in position in the hole 12, see
Figure 1, project beyond the orifice,9 thereof, the segment bars 8 very slightly, and
the wedge bars 7 considerably. Also at the point 5, where the inclines 3 of the
wedges 1 cense, the bars 7 which form their continuation, instead of being coincident
and rosting against each other, as do the inner faces 2 of the wedges, as above
alluded to, spring or deviate slightly from the axial line, so as to leave an opening
10 between them sufficient for introducing an additional wedge 11 (see Figure 8),
if required, as herein-after referred to.
The above-described improved implement is used as follows:-A hole 12 of the
required diameter and length having been drilled in the mineral 13, as usually, the
segments 4 are placed therein, a space 14 being left between their inner ends and
the same end of the hole 12 (so that the wedges may have sufficient freedom of
action endways), and their bar ends 8 slightly projecting beyond the orifice 9 of the
hole; the wedge pieces 1 are then inserted between the segments 4, and pushed in
as far as can be done by hand; then (with a hammer the wedge pieces 1, 7, are
alternately driven in a little at a time until the desired fracture of the mineral 13
is effected; but if the maximum amount of expansion thus attainable is not sufficient
to fracture the mineral as desired an additional wedge 11 is then inserted at the
opening 10 above referred to, between the wedge extensions 7, 7, (see Figure 8) to
produce a sufficient amount of expansion.
The advantages of this system of duplicate wedges are obvious; because the
power of a wedge being in proportion to its tenuity on the small angle of its
inclined planes, by this system there may be obtained double the expansive forco
obtainable with a single wedge with the same expenditure of propelling power on
cach wedge. A considerably increased wedging angle can also be obtained over
that obtainable with a single wedge; these are material advantages, the object of
using the implements being to obtain a maximum expansive force against the
material forming the circumference of the hole with a minimum expenditure of
power.
According to this system also there is the further advantage of being able to
introduce an additional wedge between the others if necessary, and so increase the .
available power considerably.
Another important advantage is, that the implement can be made very
cheaply.
Of the Figures illustrating this modification Figure 1. represents a side view of
the implement when in position in the hole ready for work; Figure 2, a front end
view; Figure 3, a back end view; and Figures 4 to 7, sections respectively through
the lines a-b, c-d, e-f, and gh, Figure 1; and Figure 8, a side view of the
implement when expanded, shewing two wedges driven up, and a third inserted
ready to be driven up.

page_text: Figures 9 to 13 represent another modification of the arrangement of the above
parts, and illustrate the arrangement of two side pieces intended to be driven on to
a central wedge.
Of these Figures, Figure 9 represents a similar view to Figure 1, and Figures
10 to 13 sections respectively through the lines i-j, kl, m―n, and o—p. .
Having now described the nature and object of my said Invention, together
with the inanner in which the same is to be or may be performed or carried into
practical effect, I would remark in conclusion that I claim as my Invention, the
above-described improved apparatus for use in wedging, winning, or breaking down
coal and other minerals, and consisting in the one modification of two or more
central wedges and two side picces or segments, and in the other modification of
one central wedge and two or more wedge side pieces, these constituent parts being
of the peculiar conformation herein-above described, and as illustrated on the accom-
panying Drawings.
In witness whereof, I, the said George William Elliott, have hereunto set my
hand and seal, this Twenty-sixth day of September, in the year of our
Lord One thousand eight hundred and seventy-seven.