IMPROVEMENTS IN TOOLS, TOOL HOLDERS, AND MACHINERY FOR CUTTING OR DRESSING STONE, SLATE, MARBLE, COAL, AND OTHER SIMILAR SUBSTANCES."
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by William Bennet Adamson at the
Office of the Commissioners of Patents on the 1st September 1876.
WILLIAM BENNET ADAMSON, of Glasgow, in the County of Lanark, North Britain,
"IMPROVEMENTS IN TOOLS, TOOL HOLDERS, AND MACHINERY FOR CUTTING OR
DRESSING STONE, SLATE, MARBLE, COAL, AND OTHER SIMILAR SUBSTANCES."
The improvements constituting this Invention relate firstly to a new and improved
method of fitting the discs of stone dressing or cutting machinery with holders for
carrying the tools or cutters. Instead of dovetailing each tool holder at the
necessary distance in the disc as hitherto, pieces of steel or other suitable material
are inserted by dovetail or otherwise into the edge of the disc, or parts are left
which project from the disc. Between these projecting pieces or parts are inserted
by dovetail or otherwise bars of steel or other suitable material of the length
necessary to carry the number of tools required in each, and the tools are fastened
in these bars instead of in tool holders hitherto used. The outline of the bars varies
according to the character of tool and the method by which it is fastened.
The improvements iclate secondly to tools and tool holders.
Under the first modification the cutting part of the tool is circular or any seginent
of a circle, and of a cup or saucer form inside, and bevilled outside with a shank at
the back. A recess is made in the tool holder or bar into which the shank is fitted,
and the tool is held firmly in its place by means of a screw or pin bearing firmly
upon the shank upon any side thereof, and at any angle, but at right angles by
preference. The cutting portion of the tool may be elliptical, triangular, square,
polygonal, or any segment thereof.
Under a second modification the improved tool is of a circular cup or saucer form,
or a segment thereof, bevilled on the outside with a corresponding hollow inside
having a boss or shank at the back, and at the inside of the tool is formed a boss
brought up to the level of the cutting part of the tool or thereabouts. The tool is
inserted in a recess formed on the front of the tool holder or bar, and in the portion
thereof which projects over the tool a screw is inserted, which being screwed down
to the top of the boss of the tool keeps the tool firmly in its place; or in the case
of a tool where the cutting part is only the segment of a circle, the boss may be
dispensed with and the holding pin screwed down to the bottom of the tool. These
tools may vary in form as in the first modification.

page_text: Under a third modification the tool is of an oval form on one side and straight on
the other side, so that one side cuts the stone or other analogous material, and the other
side acts as a scraping tool to clean out the tool marks, in which case the tools are
set in the disc with the oval side and straight side to the right or left hand
alternately, and these tools so far as the holding portion theroof and the tool
holders for holding the same may be held as in the case of the first and second
modification or otherwise.
Under a fourth modification the cutting tool is constructed of thin strips of steel
or any other suitable metal, which after being slightly worn are turned and again
turned until the whole cutting portion of the tool is exhausted. By this means the
tool always keeps a sharp cutting edge. This tool is held in a tool holder, of which
the front portion is in two parts. Between these parts the tool is held in its place
by a screw or pin, and to keep the tool steadier in its position a recess may be cut
in the bottom of the tool, into which the screw or pin is fitted. The shank which
may be round, oval, square, or any other form, fits into a corresponding hole in the
disc, bar, or main portion of the tool holder, and the shank is held securely by
means of a screw or nut at the end thereof When these tools are worn on one
side, the screw is slackened, the fiont portion of the tool holder turned half round
and the screw again tightened up, and when the fresh side of the tool is worn, the
front portion of the tool holder is again turned half round, and so on until the
cutting portion of the tool is exhausted
On one part of the shank a projection or projections are formd which fit into
corresponding recesses in the main tool holder, bar, or disc, and thus prevent the
front portion from turning round.
In some cases instead of the tools being made in short pieces as hercin-before
described, they may be made in long lengths with a holder to correspond into
which they are inserted, and as the tool wears it is brought down in the holder'
until the entire piece is worn out; or instead of turning the front portion of the
tool holder half round, the tool itself may be taken out and turned round in the
holder. This form of tool may be used either in an ordinary stone sawing or facing
machine, or in a machine for planing stone, and in the latter case may be used both
as a roughing and finishing tool. Or the same tool may be used as a finishing or
scraping tool by having the requisite number fixed on the periphery of a disc,
facing drum, or barrel, and projecting slightly beyond the roughing tool as now
used for such a purpose, and it may be applied to either plane or moulded work by
altering the shape of the tool accordingly.
Another improvement in tools for cutting stone and other analogous materials
where a tool is used similar to a pick either pointed or square at the end, consists in
having the main portion of the pick tool and the point of two pieces instead of one
as at present The main portion may either be cast with the drum, or may be cast
separate and inserted in a recess in the drum and held therein by ineans of a screw,
wedge, or the equivalent thereof. At the extremity of the main portion of the pick
a recess is formed, into which a corresponding projection on the pick point is
inserted, and the pick point is held firmly in its place by a screw inserted into the
main portion and bearing upon the said projection. When a point is worn it is
taken out and another put in its place. The tools before described may be made of
steel punched, pressed, forged, or cast to the shape, or of cast iron, or of malleable
iron, or malleable cast iron, case hardened, or they may be made of the material
from which malleable cast iron is made, but instead of being fully annealed they are
only partially annealed by being exposed for a short time to the action of oxide of
iron, and then tempered like steel by being heated up and immersed in cold
water.
Another improvement in the construction of tools for cutting stone and analogous
material consists in constructing them of ground emery or corundum mixed with a
sufficient quantity of india-rubber, fibrous matter and oil to make the mixture
pufficiently plastic, and then pressed into the requisite shapes by hydraulic or other.

page_text: pressure, or a mixture of ground emery water glass and petroleum may be used and
pressed into the necessary shapes
The materials of which such tools consist are the same as that which is used in
engineers' work shops for grinding or reducing metals in the form of revolving
wheels or burrs, and of which the principal portion is ground emery. These tools
may be made of the required shape and held in the tool holders of stone cutting
machines as at present, or the material may be made into cutting discs, or it may
be fastened with screws or otherwise on the periphery of a disc made of steel or
other suitable material; in either case the cutting surface may be plane, or it inay
have serrated teeth as in the case of a circular saw for cutting wood or teeth of
other forms; or the disc may be made to work on either side thereof with a plane
surface, or with teeth or projections, or such teeth or pieces of the material may be
carried in endless chains.
Another improvement in tools for cutting stone consists in using rough ground
emery or corundum instead of diamonds as at present.
This Invention relates also to improvements in machinery for cutting or dressing
stone, and this part consists in constructing the barrels of stone dressing machines of
a series of discs placed side by side, and fitted with tool holding bars as herein-
before described with reference to saws.