A NEW OR IMPROVED STONE DRESSING MACHINE
Year: 1880

page_text: LETTERS PATENT to John Cockburn, junior, of Berwick-on-Tweed, in tho
County and Borough of Berwick-on-Tweed, Great Britain, for an Invention of
"A NEW OR IMPROVED STONE DRESSING MACHINE."
PROVISIONAL SPECIFICATION left by the said John Cockburn (junior) at the
Office of the Commissioners of Patents on the 22nd June 1880.
JOHN COCKBURN, junior, of Berwick-on-Tweed, in the County and Borough of
Berwick-on-Tweed, Great Britain. "A NEW OR IMPROVED STONE DRESSING
MACHINE."
This Invention relates to a new or improved construction of machine or
apparatus for dressing stone, which is designed to effect the dressing or cutting
operation more expeditiously, with less waste, and without the great expenditure of
power in driving the cutters or cutting mechanism which has been required with
the machines hitherto employed. The Invention comprises a new or improved
construction of rolling or travelling platform or table framing, which carries the
stones in front of a rotating disc fitted with a novel arrangement of cutters by
which the stone or stones are drossed.
The improved travelling platform consists of a rectangular table of sufficient
length to carry one, two, or moro large stones, which are laid flat or on edge, as
may be required, on a wooden board preferably fixed to the table. A strong
framing or side standard is bolted to or formed on each end of the tablo, and these
carry a longitudinal beam or girder some height over the stones, reaching from end
to end, but having lighter intermediate supporting brackets or columns when the
table is long to divide it, and admit a single stone in each of the transverse
divisions. These intermediate brackets are fixed so that when a long stone is to be
dressed they may be taken out, and clasps made to fit the upper flange of the
steadying plates are then slipped over the joints so as to form one continuous bar
or girder from end to end, thus proventing any vibration where the cutters are in
contact with the stone. Each division of the table is fitted with a steadying plate
above the stone which slides vertically in grooves or other guides formed on the
dividing brackets and end frames. When the stone or stones are laid on the table,
these sliding plates are lowered until their lower faces or wooden boards fitted
thereon bear on the upper surface of the stones to steady them, the raising or
I Price Gd

page_text: lowering of the steadying plates being effected by means of a sot of two or more
screws working in nuts fitted in the longitudinal beam above and connected to the
sliding plates below it.
The end frames and transverse guiding divisions are carried to one side of the
travelling platform or table, so that the edge of the stone however narrow can bo
made to project slightly beyond the edge of the table and be acted on by the
cutters. The whole table and framing with the stones is carried on a set or series
of small rollers on transverse horizontal spindles carried in journal bearing blocks
bolted to a long sole plate or sets of sleepers, the rollers being ranged in a horizontal
line to carry the table framing or carriage fairly, and the table is steadied and
guided during its traverse in a horizontal line by means of flanges on the bottom
which bear transversly against the inner edges of the wheels, and also by the
upper girder sliding between small rollers set in a bracket fixed to the sole
plate.
The carriage is traversed by means of a rack and pinion beneath the table, or
screw gearing actuated from an adjacent motive power shaft, and the stones mounted
on it are brought slowly in front of a large revolving disc facing the side of the
carriago and rotating in a plane parallel to the motion of the carriage, and the
stones in passing are acted on and cut or dressed by cutting tools or cutters fixed
on and projecting from the face of the disc. The cutters, which are two, three, or
more in number, are preferably ranged round the disc at slightly different radial
distances, so that the cutters in their revolution each describe circles of different
diameters; and each succeeding radial cutter after the first, or that which is furthest
from the centre of the disc, is set to project out from the face of the disc slightly
beyond the one before it, thereby niaking the cutting or dressing operation a
gradual one, which may be regulated to any degree to suit the character of the
stones being dressed by varying the amount of projection of the cutters from the
face of the disc. The cutters are inserted through the revolving disc to project at
right angles or nearly so to its face, and are fixed preferably to the strengthening
ribs or feathers at the back of the disc; and the cutters are by preference made of
chilled iron or steel of parallel section for a considerable distance from the point, so
that their cross section is not readily changed by wear.
The revolving disc is carried on the end of a strong horizontal shaft mounted in
journal bearing blocks bolted to a sole plate, so that its centre is about in line with
the centre of the stones being dressed, and the disc shaft is driven by means of
spur or other gearing from a counter shaft or by a motive power engine direct.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Cockburn (junior) in the Great Seal Patent Office on the
18th December 1880.
JOHN COCKBURN, junior, of Berwick-on-Tweed, in the County and Borough of
Berwick-on-Tweed, Great Britain. "A NEW OR IMPROVED STONE DRESSING
MACHINE."
My said Invention relates to a new or improved construction of machine 'or
apparatus for dressing stone, which is designed to effect the dressing or cutting
operation more expeditiously, with less waste, and without the great expenditure of
power in driving the cutters or cutting mechanism which has been required with
the machines hitherto employed.
And in order that any said Invention and the manner of performing the same
may be properly understood, I have hereunto appended for that purpose a Sheet of
explanatory Drawings to be hereinafter referred to, and representing a modification
of my improved stone dressing or cutting machine, and various parts shown in
detail. In these Drawings the same reference letters are used to mark the same or
like parts where repeated.
Figure 1 is a transverse vertical section of my improved machine taken as at the
lines 1 -1, in Figure 2, which is a side elevation of the same; Figure 3 is an end
elevation, and Figure 4 is a front view of the bearing block or holder carrying the
cutters and shown fixed to the revolving disc; Figures 5 and 6 are a side and end
elevation respectively of standards or frames between which the stones to be
dressed are fixed; Figures 7 and 8 are an edge and front view of a novel form of
cutter to be used with the improved machine, and Figure 9 is a sectional view
showing the mode of fixing the cutters on their carrying spindle.
Referring to these Drawings, my said Invention comprises a new or improved
construction of rolling or travelling platform or table framing A, which carries the
stones in front of a rotating disc E fitted with a novel arrangement of cutters e by
which the stone or stones are dressed. The improved travelling platform consists
of a rectangular table A of sufficient length to carry one, two, or more large
stones Z which are laid flat or on edge, as may be required, on a wooden board Å¹
preferably fixed to the table A. A strong framing or side standard A³ is bolted to
or forined on each end of the table A, and these carry a longitudinal beam or
girder A³ some height over the stones Z, reaching from end to end, but having
lighter intermediate supporting brackets or columns A' when the table is long to
divide it and admit a single stone in each of the transverse divisions, as shewn
particularly in Figure 2. These intermediate brackets A' are fitted into a socket
on the table A and pass up into the beam A³, so that when a long stone is to be
dressed they may be taken out. Each division of the table A is fitted with a
steadying plate B above the stone, and clasps made to fit the upper flanges of the
steadying plates B may be slipped over the joints, so as to form one continuous bar
or girdler B from end to end, thus preventing any vibration when the cutters are in
contact with the stone. The ends of the steadying plates B fit and slide vertically
in grooves or other guides formed on the dividing brackets A and end frames A³.
When the stone or stones Z are laid on the table A, A', these sliding plates B are
lowered until their lower faces or wooden boards B' fitted thereon bear on the
upper surfaces of the stones to steady them, the raising or lowering of the steadying
plates B being effected by means of a set of two or more screws B, either working
in nuts fitted in the longitudinal beam above and connected to the sliding plates
below it, or formed with bearing shoulders or collars above and screwed down into
sleeves b formed on the plates B, a turning_squaro' or other equivalent 6¹ being
formed on the upper end to turn the screws B². The end frames A² and transverse

page_text: guiding divisions A* are carried to one side of the travelling platform or table A, as
shown in Figure 1, so that the edge of the stone Z however narrow can be
conveniently made to project slightly beyond the edge of the table A and be acted
on by the cutters e. The whole table A and framing A, A, with the stones Z are
carried on a set or series of small wheels C, C¹, on transverse horizontal spindles or
axles c carried by a web framing A³ formed or cast on the lower side of the table A,
these wheels running on longitudinal rails C, and being made either with an inner
flange, as at C, or in the form of V wheels, as C', to run on correspondingly formed
rails which are formed on or fixed to a sole plato C. The tablo A is steadied and
guided during its traverse in a horizontal line by means of these flanges or
V grooves on the wheels C, C¹, which bear transversely against the edges of the
rails C. The table A and framing may be traversed on rollers between guides or
by other equivalent means.
The carriago A is traversed or fed forward by means of a chain or rope D, shown
dotted, and passing over pulleys D' fitting in bearing brackets D2 at each
end of the rail or sole plate C³, or it may be fed by a rack and pinion beneath
the table, or screw gearing actuated from an adjacent motive-power shaft. The
stones Z mounted on the table A are thus brought slowly in front of a large
revolving disc E facing the side of the carriage and rotating in a plane parallel to
the motion of the carriage; and the stones Z in passing are acted on and cut or
dressed by cutting tools or cutters e or e¹ fixed on and projecting from the face of
the disc E. The revolving disc E is formed with a plain face, but has three, four,
or more ribs E' (to which the cutter holders are fixed) cast on the back, as
radiating from the central boss from which the disc is carried by a spindle E
revolving in both bearings F fitted in a strong head-stock framing F bolted to the
sole-plate C, a pulley F3 being keyed on the spindle F driven by a belt from an
adjacent motive-power shaft. The disc E is shown fitted with two sets of
cutters e and e¹ of different kinds, but only one such set is used at a time, the
other set being then removed; the object of so showing the two series of cutters
e and e' being merely to indicate the mode of fitting the two different constructions
of cutters which I employ. The cutters e or e¹ which are two, three, or more in
number (four being shown) are preferably ranged round the disc at slightly different
radial distances, so that the cutters e in their revolution each describe circles of
different diameters, and each succeeding radial cutter e after the first, or that
which is furthest from the centro of the disc E, is set to project out from the face
of the disc E slightly beyond the one before it, thereby making the cutting or
dressing operation a gradual or differential one, which may be regulated to any
degree to suit the character of the stones being dressed, by varying the amount of
projection of the cutters e or e' from the face of the disc E. The cutters e or e
are inserted through the revolving disc E to project at right angles, or nearly so,
to its face, and are fixed preferably to the strengthening ribs or feathers E' at the
back of the disc. The cutters care, by preference, made of chilled iron or steel of
parallel section for a considerable distance from the point, so that their cross
section is not readily changed by wear. These cutters e are fixed in position by
means of a cross bar screwed hard up against them, which presses them against the
edges of the ribs or feathers F, while the cutting edges project through slots in the
disc E.
The cutters which I prefer to use in combination with the improved machine
consist of three, or it may be a larger or less number of circular discs e' with bevilled
edges, the outer faces of which may either be plain, as shown in Figures 4 and 9,
or formed with a large number of radial grooves e", as shown in Figures 7 and 8.
These discs e¹ are formed with squaro central holes e² which fit on to the square
end g of holding spindles G, and are there held by a nut gl and washer on the
extreme screwed end of the spindle G, the discs el being also made thicker at the
centro to keep their outer edges clear from each other. The spindles G carrying
the cutters are fitted to revolve in bushes G₁ fixed to a carrying bracket H,
which is bolted to.a fixed bracket H¹ on the revolving disc E of the dressing

page_text: machine, as shown particularly in Figures 3 and 4. These cutters el project
through slots in the disc E and are placed in advance of each other, each at a
shorter distance from the centre of the disc E than that preceding, and they are
also made to project each a little further from the face of the disc E than that
preceding, as already described. In order to be able to effect this adjustment from
the face of the disc E, the bearing bush G₁ of the cutter spindle G is fixed in a
movable plate H, sliding at an angle on the bracket H, and bolted thereto after
adjustment. The revolving disc E is carried on the end of the horizontal shaft E³,
at such a height from the sole plate C that its centre is about in line with the
centre of the stones Z being dressed, and the disc shaft E³ may be driven by means
of spur or other gearing from a counter shaft or a motive power engine direct,
instead of by the pulley F shown.
In some cases, as for cutting a bevilled edge on stones, the machine may be fitted
with brackets I bolted to the table A, as shown in Figures 5 and 6, these brackets I
having swivelling centre plates or chucks I', between which the stone is held and
carried. The chucks 1' are fitted with short spindles i carried in bearings in the
bracket I, and may be turned round to place the edge of the stone at any anglo by
moving a hand lever 12 outside, fitted on the outer end of one of the spindles i, the
handle I being secured at the desired angle by a nut and bolt i passing through
the bandle and through a slot in the bracket I, and the stones being held by
toothed projections or catches on the faces of the chucks I', which are also
adjusted to grip the stone by a screw spindle at one end.
Having thus described the nature of my said Invention, and the manner of
performing the same, I havo to stato that I do not confine myself to the precise
details herein described or delineated, but what I consider to be novel and original,
and therefore claim as the Invention secured to me by the hereinbefore in part
recited Letters Patent is,-
First. The general arrangement and construction or combination of the parts of
a stone dressing machine, in which the stones to be cut or dressed are traversed by
a travelling carriage or table A, carrying and gripping the stones with their faces
vertical or inclined in front of a revolving disc E carrying the cutters c or c¹,
substantially as and for the purposes herein described in reference to the
accompanying Drawings, or any mere modification thereof.
Second. In stone dressing machines, in which tho stones to be cut or dressed are
traversed on a travelling table or carriage, the arrangement, construction, and fitting
on a stationary head-stock of the revolving cutter disc E in front, with differential
radial and projecting plain fixed cutters e, or equivalent disc cutters c¹ on revolving
spindles, adjustably secured thereto, all substantially as and for the purposes herein
described in reference to and shown in the accompanying Drawings, or any mere
modification thereof.
In witness whereof, I, the said John Cockburn, junior, have hereunto set
my hand and seal, this Fifteenth day of December, in the year of our Lord