Improvements in Coal Cutting Machinery.
Year: 1895

page_text: Date of Application, 21st Aug., 1895
Complete Specification Left, 19th May, 1896-Accepted, 20th June, 1896
PROVISIONAL SPECIFICATION.
Improvements in Coal Cutting Machinery.
We, FREDERICK WILSON HURD, of 1, Alfred Terrace, Hillhead, in the
County of Glasgow, North Britain, Engineer, and JOHN JAMES MILLAR, of the
same place, Cashier, do hereby declare the nature of this invention to be as
follows, that is to say :-
This invention relates to coal cutting machinery of the kind in which a long bar
armed with cutters is arranged to act on the coal, and it comprises an improved
construction of such bar and parts appertaining thereto.
In carrying out the invention, the cutter bar, which as in some existing coal-
cutting machinery, is made to rotate and also to reciprocate, is made with a body
part, which is cylindrical or tapering, and has formed on it a projecting spiral or
helical thread of a comparatively small pitch, the spaces between the convolutions
of the thread serving for the free egress of the dust or portions of coal detached in
the cutting operation. A number of cutters are fixed to the helical thread, or to
the body of the bar, either by being secured in holes formed through the thread
and bar, or by being formed with dovetailed backs secured in dovetailed sockets in
the thread, or in any other convenient way.
The bar may be cast with the helical thread, or the thread may be produced by
turning or removing the metal between the threads; and the thread may be of
uniform or varying pitch.
Dated this Twentieth day of August 1895.
EDMUND HUNT,
Applicants' Agent.
Improvements in Coal Cutting Machinery.
We, FREDERICK WILSON HURD, of 1, Alfred Terrace, Hillhead, in the
County of Glasgow, North Britain, Engineer, and JOHN JAMES MILLAR, of the
same place, Cashier, 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, that is to say :-
This invention relates to coal cutting machinery of the kind in which a long
bar armed with cutters is arranged to act on the coal, and it comprises an
improved construction of such bar and parts appertaining thereto. The cutter
bar as in some existing coal-cutting machinery, is made to rotate and also
to reciprocate.
A cutter bar as made with the present improvements is represented on an
accompanying sheet of explanatory drawings with reference to which it is herein-
after particularly described.
Figure, 1, of the drawings is a side elevation, Figure, 2, is a sectional end
elevation, the section being as at a-a, in Figure, 1.
Figure, 3, shows a second modification of the smaller end of the bar.

page_text: Figures, 4, and 5, are a plan and a cross section, enlarged, showing one form of
cutter and mode of securing it; and Figure, 6, is a corresponding longitudinal
section.
In these drawings the same reference letters are used to mark the same or like
parts wherever they are repeated.
The cutter bar, B, which is made with a flange, A, for bolting it by to the parts
of the machine which holds and drives it, is made with a body part which may be
cylindrical but is shown tapering, and has formed on it a projecting spiral or
helical thread, H, the spaces between the convolutions of the thread serving for
the free egress of the dust or portions of coal detached in the cutting operation.
Numerous cutters, C, are.fixed to the helical thread, H, or it might be to the body
of the bar, either by being inserted in holes formed through the thread and bar,
as shown in Figures, 1, and 2; or by being formed with dovetailed backs secured
in dovetailed sockets in the thread as shown in Figures, 4, 5, and 6, or in any other
convenient way.
The bar, B, may be cast with the helical thread, H, or the thread may be
produced by turning off or removing the metal between the threads; and the
thread may be of uniform or varying pitch. At the end of the bar, B, one or more
cutters, as at, D, may be bent so as to cut just beyond the edge of the bar; or an
auger point, E, Figure, 3, may be fixed to the end of the bar. When it is desired
to form a comparatively small hole or cut the cutters may be fixed in a bar made
without the helical thread; and a separate small bar with a helical thread formed
in it may be arranged parallel to and near the cutter bar and be made to rotate so
as to clear away dust and small broken coal.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
:―
The improved construction of cutter bar for.coal cutting machinery.substantially
as herein before described and shown in the accompanying drawings.
Dated this Eighteenth day of May 1896.
EDMUND HUNT,
Applicants' Agent.