IMPROVEMENTS IN WEDGING APPARATUS APPLICABLE TO BREAKING DOWN COAL AND OTHER SUBSTANCES.
Year: 1878

page_text: LETTERS PATENT to Jonathan Harrison, of Coalville, in the County of
Leicester, Mining Engineer, F.G.S., for the Invention of "IMPROVEMENTS IN
WEDGING APPARATUS APPLICABLE TO BREAKING DOWN COAL AND OTHER
SUBSTANCES.
"
Sealed the 19th July 1878, and dated the 21st January 1878.
PROVISIONAL SPECIFICATION left by the said Jonathan Harrison at the
Office of the Commissioners of Patents on the 21st January 1878,
JONATHAN HARRISON, of Coalville, in the County of Leicester, Mining Engineer,
F.G.S. ❝IMPROVEMENTS IN WEDGING APPARATUS APPLICABLE TO BREAKING DOWN
COAL AND OTHER SUBSTANCES."
These improvements relate to wedging apparatus for breaking down coal after
the said coal has been "holed."
It is the practice after "holeing" the coal to break it down, or detach it from the
main body of the coal by wedges, and it is the function of the wedge to detach or
break down as much as possible of this coal.
My improved wedging apparatus will break down the coal in larger quantities
than the common wedge in ordinary use, and it is as effecient in operation as other
wedging apparatus of more complicated design and expensive construction.
My improved wedging apparatus consists, firstly, of a strong parallel tube which
is divided into two equal parts in the direction of its length, the said tube (in two
parts) has its internal diameter parallel, but larger at its front end for, say, one-
fifth or one-sixth of its length, and smaller in diameter for, say, the remaining four-
fifths or five-sixth of its length, or thereabouts; but I do not now fix any pro-
portions for the lengths of the large and small internal diameters of any wedge
tube.
The front end of my tube is that which first enters the hole in the coal, and the
back end is that nearest the operator.
My improvements consist, secondly, of a wedge of a peculiar and novel description,
which will be driven into the aforesaid tube, and expand each half thereof, and so
Dins G72

page_text: exert a great pressure on the coal. The said wedge is a combination of the
ordinary flat wedge and the ordinary round taper plug wedge, the round portion
being at the front end, and the flat portion at the back, and that portion of it
between the round and flat parts being flat with the half of a round taper plug on
each side, thereby forming a compound wedge, the round portion of which will act
at or towards the front end of the tube, the half-round and flat parts (combined)
will act at or about the centre, and the flat portion will act at or towards the back
end of the tube, the flat portion of the wedge acting on the flat portions of the sides
(so to speak) of each half of the tube.
The tube (in two parts) and the compound wedge may be made of steel or other
suitable material, and may either be used as first formed, or may be turned, bored,
planed, or otherwise machined or fitted.
When the tube and wedge are placed in position, and the wedge is actuated by
blows from a hammer, or otherwise, the coal will be broken down at or near the
front end of the wedge, as well as at the back end thereof.
If the combined plug and wedge does not break down the coal in the first
instance, other wedges can be used at the back of it, as in the ordinary way of
wedging down coal or other material.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Jonathan Harrison in the Great Seal Patent Office on the 20th
July 1878.
JONATHAN HARRISON, of Coalville, in the County of Leicester, Mining Engineer,
F.G.S. "IMPROVEMENTS IN WEDGING APPARATUS APPLICABLE TO BREAKING DOWN
COAL AND OTHER SUBSTANCES.”
This Invention relates to improvements in apparatus for breaking down masses
of coal and other minerals and substances as used in mining or quarrying the
same.
The apparatus consists of two pieces of grooved iron, steel, or other suitable
material, herein-after termed the feathers, the grooves therein being in the direction
of the length thereof, and tapered towards each end thereof.
The apparatus further consists of a compound or combined wedge of iron, steel,
or other suitable material, which is circular in cross section in the front portion,
both circular and rectangular in cross section in the next portion, and rectangular
only in cross section in the remaining portion so far as it acts on the feathers, and
is of any convenient form in cross section in the back portion which does not act on
the feathers, but which is operated on to drive the wedge along and between the
two feathers.
In using the apparatus the following means can be employed, that is to say:-
The coal having been "holed" in the ordinary manner, and to the usual depth and
distance, a hole is drilled to receive the wedging apparatus, at the level at which
it is desired to fracture the coal, the hole being drilled a few inches beyond the

page_text: furthest point to which the front end of the feathers enter, and a few inches short
of the furthest point to which the coal is holed. The two feathers are then
placed in the hole, and the compound wedge being driven in between them lifts
or acts at or near the back end of the "holing" before it lifts or acts at the front
thereof.
The accompanying Sheet of Drawings clearly illustrate the improved apparatus,
by reference to which and the above description my Invention can be carried into
effect.
°
Fig. 1 is a plan of the under side of the top feather, or the top side of the bottom
feather, showing the tapered groove.
Fig. 2 is a longitudinal section of the feather showing the tapered groove.
Fig. 3 is a plan of the upper or under side of the compound wedge.
Fig. 4 is a side view of the compound wedge.
Fig. 5 is a side view of a complete apparatus showing the wedge driven
home.
Fig. 6 is an end view of the feathers.
Fig. 7 is the front end view of the apparatus, showing the compound wedge
driven home.
Fig. 8 is the back end view of the apparatus, showing the compound wedge
driven home.
Having now particularly described and ascertained in what manner my said In-
vention is to be or may be performed or carried into effect, I wish it to be under-
stood that what I claim as novel and original and secured to me by the herein-
before in part recited Letters Patent is, "Improvements in apparatus for wedging
down or breaking down coal or other minerals or substances," substantially as
herein specified, described, and illustrated by the accompanying Sheet of
Drawings.
In witness whereof, I, the said Jonathan Harrison, have hereunto set my
hand and seal, this Seventeenth day of July, in the year of our Lord One
thousand eight hundred and seventy-eight.
JONATHAN HARRISON. (LS)