IMPROVEMENTS IN APPARATUS FOR GETTING COAL AND OTHER MINERALS
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by George Edmund Donisthorpe
at the Office of the Commissioners of Patents, with his Petition, on
the 13th April 1868.
I, GEORGE EDMUND DONISTHORPE, of Leeds, in the County of York,
Merchant, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS FOR GETTING COAL AND OTHER MINERALS," to
be as follows:-
!..
When getting coal by means of apparatus carrying picks or cutters
which as the apparatus is moved forward have a rectilinear to-and-fro
motion given to them to cause them to cut a groove into the coal or
mineral, some difficulty is experienced in removing from the groove the
small pieces cut away by the cutter, these small pieces also cake together
into a hard mass at the bottom of the groove and considerably increase
the resistance offered to the cutter at the end of its stroke, as the pieces.
cannot pass away. Now according to my Invention in order to facilitate
the breaking off and removal of the pieces which are to be cut away, by
the cutter. at the end of its stroke I employ in combination with such

page_text: cutter a light lever pick which works in the groove cut by the first
cutter; this lever pick turns at one end on an axis carried by the
machine, and at its other end carries a cutter. Before each blow of the
rectilinear reciprocating cutter a blow is given with the lever pick,
and its cutter then acts to clean or cut smooth the bottom of the groove,
and also to penetrate a short distance into the coal or mineral at the
back of the slice or strip which is to be cut away at the next stroke
of the rectilinear reciprocating cutter, the bottom of the groove being
thus rendered smooth and even and the slice or strip to be removed by
the rectilinear reciprocating cutter being undercut at its end, the slice
or strip will readily be cut off as the pieces will be able readily to break
off and to pass away. In order to remove the pieces so cut away from
out of the groove in the coal or mineral the stem of the lever pick has
projecting from it along its under side a plate which lies close to the
bottom of the groove, and the lever pick, after it has made its stroke,
is not moved back until the rectilinear reciprocating cutter has com-
pleted its stroke; the pieces cut away by the rectilinear reciprocating
cutter are thus received on the plate, the lever pick is then turned back
slowly on its axis so as to draw it back out of the groove in the coal
or mineral, carrying back with it the pieces which are resting on the
plate carried by the stem of the lever; the pieces may then be removed
.therefrom by any suitable means. The light lever pick may be actuated
by any suitable means, but I prefer to employ for this purpose a second
air cylinder or engine in addition to the air cylinder or engine usually
employed for working the rectilinear reciprocating pick, the air cylinder
which works the lever pick might then also be caused at the same time
to give the forward movement to the machine.
Apparatus such as is above described might be employed for simply
removing from the groove the pieces cut away by the cutter without
using a cutting tool at the end of the lever arm, but I believe it to be
always more advantageous for the lever arm to carry at its end a cutting
tool, as above described; the pieces cut away by the rectilinear recipro-
cating cutter might also be caused to pass over the top of the lever arm
and be then swept back by it out of the groove on the return or backward
movement of the lever arm. The lever arm of lever picks might also
:similarly carry a plate to receive the pieces as they are cut away by the
cutter of the pick and to carry them back out of the groove. A fixed

page_text: stop projecting from the machine into the groove in the coal or mineral
might then be used to prevent the pieces as they are cut away being
driven back along the groove, so that at the end of the stroke of the
pick all the pieces cut away may be received on to the plate.