IMPROVEMENTS IN MACHINERY OR APPARATUS FOR CUTTING, PROAL SPATION Cutting, DRESSING, PLANING, TURNING, AND SHAPING STONE
Year: 1875

page_text: LETTERS PATENT to John Dickinson Brunton, of Leighton Crescent,
Kentish Town, in the County of Middlesex, Engineer, for the In-
vention of "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR CUTTING,
PROVISIONAL SPECIFICATION left by the said John Dickinson Brunton
at the Office of the Commissioners of Patents, with his Petition,
on the 25th February 1875.
I, JOHN DICKINSON BRUNTON, of Leighton Crescent, Kentish Town,
in the County of Middlesex, Engineer, do hereby declare the nature of my
said Invention for "IMPROVEMENTS IN MACHINERY OR APPARATUS for Cutting,
DRESSING, PLANING, TURNING, AND SHAPING STONE," to be as follows :—
This Invention consists of improvements in the method of applying
circular cutters to the cutting, dressing, planing, turning, and shaping
stone. I fix on a shaft or spindle a chuck carrying one or more circular
-cutters which are free to rotate on their own axis, and I give to this

page_text: s
spindle a very rapid revolving motion. On the arbors of the cutters I
place wheels or rollers and cause them to revolve in contact with tho
internal face of a hoop, by which means I give to the cutters such a
rotation on their axes as shall cause their contact with and passage over
the surface of the stone to be of a rolling nature. I bring the stone to
be operated upon into contact with the rapidly revolving cutters, which
cutters by the means already described have such an axial rotation as
causes their edges to roll upon or against the surface of the stone.
Contact with the stone adjusts any small difference that may exist
between the rotatory motion required and that imparted by the rollers or
wheels and hoop. For the purpose of permitting this adjustment the
rollers are not keyed or otherwise immoveably fixed on the cutter arbors,
but have a certain frictional hold only upon them. To the same end
the hoop itself is susceptible of a variable circular motion round the
spindle axis.
To the stone is given a motion rectilineal, circular, or otherwise, as
may be desired, so as to cause the rotating cutters to plane, shape,
mould, or turn the surface of the stone to the required figure.
C
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Dickinson Brunton in the Great Seal Patent 2
Office on the 25th August 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DICKINSON BRUNTON, of Leighton Crescent, Kentish Town, in the
County of Middlesex, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 1
Letters Patent, bearing date the Twenty-fifth day of February, in the
'year of our Lord One thousand eight hundred and seventy-five, in the
38th year of Her reign, did, for Herself, Her heirs and successors, give
'and grant unto me, the said John Dickinson Brunton, Her special
license, that I, the said John Dickinson Brunton, my executors ad-
· ministrators, and assigns, or such others as I, the said John Dickinson
Brunton, my executors, administrators, or assigns, should at any time
agree with, and no others, from time to time, and at all times there-
after during the term therein expressed, should and lawfully might

page_text: Toothed gearing may be employed in lieu of frictional wheels or
rollers, in which case the hoop may be either dispensed with or may
become an internal toothed wheel or ring.
The stone has imparted to it a rectilureal, circular, or other motion, as
desired, so as to cause the rotating cutters to plane, shape, or mould the 5
surface of the stone to the required figure.
And in order that my said Invention may be fully understood, I shall
now proceed more particularly to describe the same, and for that purpose
shall refer to the several Figures on the annexed Sheet of Drawings, the
same letters of reference indicating corresponding parts in all the 1
Figures.
Figure 1 of my Drawings represents a sectional elevation of a chuck
carrying circular cutters, arranged and operated according to one mode
of carrying out my Invention.
Figure 2 is a detail to be herein-after referred to.
Figure 3 is a sectional elevation illustrating a modification of the
arrangement Figure 1.
Figure 4 is a front elevation; and Figure 5 is a side clevation of a
planing machine shewing one mode of mounting a chuck with its
cutters for the purpose of producing plane surfaces on stone. A, Figure 1, 2
is the chuck keyed or otherwise fixed upon the end of the spindle B and
carried round with it as it revolves. a is an inclined boss forming part
of the chuck A. I prefer to employ three of the bosses a, but there
should be at least two such bosses on a chuck. Each boss is bored out
to contain a socket b, through the centre of which passes the cutter
bolt c; the conical head of the cutter bolt c fits into a conical hole in
the centre of the circular cutter d, which by means of the nut e is held
firmly against the socket b, the cutter, cutter bolt, and socket all rotating
together as one piece in the boss a. On the upper end of the socket
which projects above the boss a I fix a roller f, so that by turning this
roller I turn the socket, cutter bolt, and cutter. The roller ƒ may either
be keyed upon the socket 6 or mounted loosely thereon, and secured in
such a manner as to be self-adjustable by means of springs e¹, e¹, fitted
in slots formed in the boss f¹ of the roller ƒ so as to bear against and
have a frictional hold upon the socket 6, as shown in the detail, Figure 2,
or by other suitable means. Upon the spindle B between the neck b¹

page_text: and the chuck A, I mount a belt pulley g which is free to rotate inde-
pendently of such spindle. To this pulley g there are attached arms h, h,
having fastened to their extremeties. a hoop i lined with india-rubber,
leather, or any other suitable substance to give it on its internal face a
better contact with and hold upon the edge or circumference of the
rollers f, or I make the hoop i an internal toothed wheel or ring, and
the rollers toothed wheels gearing into it.
It will be obvious that if while the chuck with its cutters and their
rollers is revolving the hoop is held stationary, the cutters will by virtue
of the contact of the rollers with the interior of the hoop i or by virtue
of the engagement of their teeth with the teeth of the hoop or ring i (if
teeth are employed) make such a number of rotations on their own axis
while making a revolution round the central axis of the spindle B, as is
the product of the internal diameter of the hoop divided by the diameter
of the rollers; also that the number of rotations of the cutters for one
revolution of the central spindle may be governed or determined by
giving to the hoop itself by means of the belt pulley 9 any number of
revolutions either in the same direction as the spindle B revolves or
contrary to it.
The object to be attained in practice is to impart to the cutters & such
a number of revolutions as shall cause the edge of the cutters d to roll
and not to rub upon the stone. By means of this Invention therefore
the cutting discs have imparted to them a positive rotatory motion on
their own axes independently of the rotation which they derive from
their contact with the stone.
In the modification (Figure 3) the pulley g has cast upon or attached
to it a toothed wheel working into an intermediate pinion 7 which is
mounted on a pin in the chuck A and gears into a toothed wheel m
keyed on the socket b. By this means also there is imparted to the
cutters a certain positive rotation, the rate of which can be determined
by means of a belt controlling or regulating the revolutions of the
central wheel k.
Figures 4 and 5 illustrate one mode of applying a chuck with its
discs to a machine for producing plane surfaces on stone.
In the example shewn the arrangement of roller and hoop herein-
before described with reference to Figure 1 is adopted, but the modifi-
cation, Figure 3, may be substituted therefor if desired. The spindle B

page_text: is driven by means of the pulley C, and its lower end is supported on
bearings n, n, carried on a slide D, which latter is capable of being
moved from side to side of the machine by means of the screw E, and of
receiving with the cross slide F a vertical movement by means of the
vertical screws G, G, as in an ordinary metal planing machine. H, H, are
the standards of the machine, and I is the bed on which the stone K to
be operated on is fixed. The bed I rests upon slides or rollers o, o, and is
moved either by a rack and pinion L (as shewn on the Drawing), or by
a screw, or any other of the well known methods of giving motion to
planing machine tables. Between the bearings n, n, may be placed a
cone series of pullies p, from which by means of a belt to a similar cone
series p¹ the latter may derive motion. The cone pullies p¹ are mounted
on a shaft q supported in brackets r, r, extending from the slide D,
which shaft also carries a pulley & for transmitting motion by means of
a belt to the central pulley g which governs the rotation of the cutter,
as before described, or the pulley g may be driven or controlled by any
other convenient means. The spindle B, in addition to being carried in
the bearings n, n, is further supported by means of a guide or stay M
carrying a bearing through which the spindle B is free to slide as the
slide F is raised or lowered, such bearing & being also free to slide along
the guide or stay M as the slido D is moved from side to side of the
machine.
In operating with the machine the slide D is fixed in such a position
as that when the stone to be dressed comes into contact with the
revolving cutters they shall chip away from off the surface, the depth of
chip varying according to circumstances and the nature of the stone.
The spindle B is set in rapid rotation, and the table I as it travels brings
the stone against and carries it along under the revolving discs which
chip away from and dress the surface operated on.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is, imparting
to cutting discs supported on axes arranged around or at the side of a
central or main axis a positive rotatory motion on their own axes inde-
pendent of the rotation which they derive from their contact with the

page_text: stone under operation, substantially as and for the purpose herein-before
described and as illustrated by my Drawings.
In witness whereof, I, the said John Dickinson Brunton, have to
this my Specification set my hand and seal, the Twenty-first
day of August, One thousand eight hundred and seventy-five.
JOHN DICKINSON BRUNTON. (L.s.)