IMPROVEMENTS IN MACHINERY FOR DRESSING OR SURFACING STONE, MARBLE, AND SIMILAR MATERIALS
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by William Henderson at the
Office of the Commissioners of Patents, with his Petition, on the
14th October 1875.
I, WILLIAM HENDERSON, of Glasgow, in the County of Lanark,
North Britain, Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MACHINERY FOR DRESSING OR SURFACING
STONE, MARBLE, AND SIMILAR MATERIALS," to be as follows, that is to
say:―
This Invention relates to improved machinery specially adapted for
the application of a multiple graduated diamond tool for dressing or
surfacing stone, marble, and similar materials, the said tool being by
preference of the kind used by Robert Young and Thomas Thomson,
who applied for Letters Patent therefor on 24th April last (No. 1509).
In one arrangement of the improved machinery a long carriage or
sliding bed arranged to move horizontally on guides as in a metal
planing machine, is formed with vertical side and end flanges provided
with hand wheel screws for securing a number of blocks of stone, which
are set on the bed and jammed together by wedges or screws. The

page_text: sliding bed is moved directly by a long cylinder, in which steam, water,
or other fluid under pressure is employed. The cylinder may
be
stationary and the piston be connected to the sliding bed, or the
cylinder may be formed in or attached to the bed. The tool holder is
mounted as in a metal planing machine on a cross guide frame
adjustable vertically on a pair of connected stationary side standards.
In some cases a saving of space and power may be obtained by making
the bed on which the stone blocks are fixed stationary, and by giving
the necessary horizontal movement to the framing carrying the tool
holder.
In a second arrangement the tool holder is adjustably attached to one
end of a horizontally sliding ram, to which a short reciprocating
traverse is imparted by a revolving crank, the crank being connected to
the ram by a rod or acting in a vertical slot in the ram or in a piece
connected to it; or the ram may be directly moved by means of a
stationary cylinder or by means of one formed in or attached to the ram
itself and worked by steam or other fluid. The blocks of stone are
secured by hand wheel screws on a sliding bed, which has imparted to
it a slow intermittent progressive motion at right angles to the traverse
of the tool ram. The sliding bed is by preference supported and guided
by means of flanges and wheels on its inner side, and moving on guido
rails or flanges formed in the vertical face of the stationary frame
carrying the tool ram and driving gearing. In some cases the bed on
which the stone blocks are fixed may be stationary, and the progressive
motion be imparted to the tool ram. When the length of stroke makes
it desirable an outside bearing is provided for the tool ram.
In the first and second arrangements it is the top face of the stone
which is dressed, but in a third arrangement the dressing action is
applied to a vertical face of the stone, a vertical reciprocating movement
being given to the tool holder, whilst a horizontal progressive movement
is given to a sliding bed or case, on or in which the stone is secured by
hand wheel screws; or the stone may be stationary and both horizontal
and vertical movements be imparted to the tool holder. The tool holder
is fixed on the bottom end of a vertical slide mounted and moved like
the tool bar of a metal slotting machine, or it may be moved directly by 3
means of a cylinder worked by steam or other motive fluid.
In the three arrangements herein-before described the progressive
motion is made intermittent, and to take place after each single stroke

page_text: or each movement in either direction of the tool holder, and in the
second and third arrangements the stroke of the tool holder is made
somewhat longer than the breadth of stone acted on.
In a fourth arrangement a moving bed or box in which one or more
blocks of stone are fixed is mounted like a turntable or otherwise so as
to revolve about a vertical axis, and a slow continuous feed motion is
given to the tool holder. If the feed motion is at right angles to the axis
of revolution of the stone a flat dressed surface will be formed; but
the tool holder may be moved along an inclined or curved guide so
as to produce a conical, spherical, or other surface of revolution.