IMPROVE- BEING ADDIDING BAD Dore MITMONDS
Year: 1868

page_text: LETTERS PATENT to John Thomson King, of Liverpool, in the County
of Lancaster, Consulting Engineer, for the Invention of "IMPROVE-
BEING ADDIDING BAD Dore MITMONDS
"
Sealed the 25th September 1868, and dated the 26th March 1868.
PROVISIONAL SPECIFICATION left by the said John Thomson King
at the Office of the Commissioners of Patents, with his Petition, on
the 26th March 1868.
I, JOHN THOMSON KING, of Liverpool, in the County of Lancaster,
Consulting Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN APPARATUS FOR DRESSING MILLSTONES," to be as
follows:-
My Invention consists essentially in the employment of a tool or
drill tipped or fitted with a central cutting point of "bort" or other
hard stone or substance to which I give a rapid rotatory motion on
its own axis, and at the same time a to-and-fro movement over the
stone to be dressed, so that without the said cutting point leaving the
millstone grooves of any desired depth and width can be formed on
the face thereof.

page_text: In carrying my Invention into effect I rest framework on the face
of the stone to be dressed, and by power from any convenient source
through the agency of cords, bands, or gearing cause the drill or tool
tipped as aforesaid with a hard substance and supported in a sliding
piece or its equivalent to rotate at high speed. The sliding piece is
carried by the frame and by a lever operated by hand or otherwise
made to move to and fro over the stone. To traverse the said drill
or tool laterally for a new cut or groove I fit to the sliding piece above
mentioned another transverse sliding piece, and by a tappet wheel and
intercepting piece or their mechanical equivalents cause such transverse
sliding piece to be traversed automatically, or the movement for the
new cut can be effected by operating the tappet wheel or a ratchet by
hand.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said John Thomson King in the Great Seal Patent
Office on the 26th September 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
THOMSON KING, of Liverpool, in the County of Lancaster, Consulting
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of March, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs, and successors,
give and grant unto me, the said John Thomson King, Her special
license that I, the said John Thomson King, my executors, adminis-
trators, and assigns, or such others as I, the said John Thomson King,
my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter
during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United
the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN APPARATUS FOR DRESSING MILLSTONES,
upon the condition (amongst others) that I, the said John Thomson
King, my executors or administrators, by an instrument in writing
وو

page_text: under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Thomson King, do hereby
declare the nature of my said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
accompanying Drawings, and to the figures and letters thereon, that is
to say:
My Invention consists essentially in the employment of a tool or
drill tipped or fitted with a central point of "bort" or other hard
stone or substance to which I give a rapid rotary motion on its own
axis, and at the same time a to-and-fro movement over the stone to
be dressed, so that without the said cutting point leaving the millstone,
grooves of any desired depth and width can be formed on the faco
thereof..
In carrying my Invention into effect I rest framework on the face of
the stone to. be dressed. and by power from any convenient source
through the agency of cords, bands, or gearing cause the. drill or tool
tipped. as aforesaid with a hard substance and supported in a sliding
picce or its equivalent to rotate at high speed.. The sliding piece is
carried by the frame and by a. lever operated by hand or otherwise made
to move to and fro over the stone.. To traverse the said drill or tool
laterally for a. new cut or groove I. fit to the sliding piece above
inentioned another (transverse) sliding piece, and by a tappet wheel and
intercepting pieces.or their mechanical equivalents: cause such transverse
sliding piece to. be traversed automatically, or the movement for each.
successive new cut or groove can be effected by operating the tappet
wheel or a ratchet by hand..
Sheet A of the accompanying Drawings contains views illustrative of
apparatus or a machine according to my Invention, the said apparatus.
or machine being so constructed that it can be readily adjusted for
dressing millstones with either right or left master lines and furrows, and'
so formed that a full "quarter" of a millstone can be dressed without
moving the frame..

page_text: Fig. 1 is a plan view; Fig. 2 a side elevation; and Fig. 3 a
transverse section at the line A, B. Like letters and figures. denote the
same parts in both views.
The frame in this modification is shewn made of two castings marked
respectively a and a*, and these parts are joined together by a feather_on
one hand and a groove on the other to allow the part a to be moved to
one side or the other to suit the angle or direction of the master lines
and furrows, and "land" to be dressed. Set screws or their equivalents
can be used when necessary to bind them firmly together. bare support-
ing feet fitted with adjusting screws to level the machine on the face of
the stone; it will be obvious however the under side of the frame a can
be planed true and the feet connected thercto dispensed with. The foot
and arm of the part a* can also be dispensed with; and in this case the
central socket formed to receive the end of the millstone spindle when
the machine is in position for dressing a millstone may be cast in one
piece with the part a. If desired pinching screws passing through the
metal of the socket can be employed to fix the machine on the millstone
spindle. In all cases it is desirable to provide a socket to receive the
end of the spindle or a stud fitted in the top stone when turned over, so
as thereby to centre the machine correctly. c is a sliding picee in which
the diamond tipped tool d is carried; this sliding piece bears on the
frame a at both sides and is caused to move to and fro over the stone
by the link e and handle f, the latter being centred on a stud fixed in a
bracket g secured to the frame a. h is a pulley receiving motion from
any available power; and i are guiding pullies over which the endless
driving cord or band jis led. The pullies i rotate on fixed studs. This
cord or band is passed around the diamond tipped tool d so that the tool
is caused to rotate at the travelling speed of j. The tool d rotates in the
transverse sliding piece or carrier k, and the depth of the cut required to
be made by the diamond is regulated by the collar I, which is screwed on
its external surface to take into a female screw in k, a graduated flange
being formed on 1, and a pointer m provided so that the tool can be
moved up or down a short distance with great nicety. A collar is formed
on d to prevent it from rising when at work, and another movable collar
is secured to it by a pin or otherwise to prevent it from falling down and
to allow of easy removal from the carrier with 7. The diamond can be
fixed in its place with soft metal, as is the practice with lapidaries, or
in a recess or space lined with soft metal and covered by a cap provided
with an opening through which a point of the diamond projects, as

page_text: is shewn on the Drawings. In practice the diamond acts most effectively
when rotated at a high speed, say up to 15,000 revolutions a minute.
The sliding piece or carrier / is caused to traverse laterally for the
purpose of making a new cut by the screw m, which is carried by c and
passes through, the tappet wheel n, and intercepting piece o. Every
time the piece c is brought out to the skirt of the stone the wheel n comes
in contact with o and is caused with the screw m on which it is affixed
to make a partial revolution; this propels the carrier k laterally the
required distance. The machine as here shewn is so arranged that the
diamond moves twice over the same surface or makes a double. stroke to
form one groove, but it will be obvious intercepting picces could be
placed at both ends of the frame and lateral movement be caused at
the end of each single stroke; it will also be obvious that by varying
the pitch of the teeth of n the number of grooves in a given space can be
increased or decreased.. Instead of using an automatic feed of the
kind described a, ratchet or other hand feed could be used. The
operate the machine after it is placed in proper position on the stono
and the diamond tipped tool adjusted to make a cut of the proper
depth, it is simply necessary for the attendant to put the machine in
gear, so as to rotate the tool and then to move the handlef to and fro.,
This machine, it will be observed, can be used by simply adjusting the
diamond tipped tool for dressing the angular sides of the master lines
and furrows.
Sheet B of the accompanying Drawings contains three views, Fig. 1
being a plan; Fig. 2 a side elevation; and Fig. 3 a longitudinal section
at the line C, D, all of apparatus or a machine adapted to dress a full
"quarter" of a millstone without moving the frame. Like letters denote
the same parts.
"
Here the frame is made of two castings a', a, bolted together, planed
true on their under surfaces to level the machine on the stone. A
socket to pass over the spindle c', or a stud in the top stone is
provided to centre, the frame, and if necessary secure and steady it in
position when at work; d¹ is a sliding piece or bar bearing on the two
end parts of a; it is caused to traverse laterally for each new cut, as
hereafter is set forth. e¹, the tool carrier, and f¹, the diamond tipped
tool. The said tool carrier is made to move to and fro by means of
the handle g' and link ', the former is supported on a stud carried by
the frame picce . The upper end of the diamond tipped tool f' works

page_text: against and is adjusted by means of the screw. in the thrust piece k¹.
The carrier e¹ is bushed to steady f' and reduce friction, and a
spring is provided to prevent f¹ from falling when at work into
hollows on the face of the stone and for easy removal from the carrier.
The tool is made to rotate at a high velocity by the endless cord m³,
which passes over a small pulley on the tool and also over the shifting
pulley . Pulley n¹ is secured on a spindle, whereon there is also
affixed another pulley o', which latter receives motion by a cord or
band p from pulley q'; o is secured on a driving shaft resting on the
top of the socket b', and receives motion by the pulley, or in any other
convenient manner from any available power. The pulley n¹ is supported
on the movable arms a jointed, so that in every position in whichi
it is possible to move the tool f¹ and its earrier e and the sliding
piece d the cords will always be in proper tension. To obtain speed
the pullies it will be observed are made of different diameters. The
lateral traversing of d with e¹ and f¹ is effected by the tappet piece f³,
and the parts immediately to be mentioned. Each time t comes to
the outer end of the stroke it strikes against the lever secured on
the rocking shaft 2 supported in the frame a³, a²; u³ is coupled at one
end by a link us to the sliding bar v', whereto two pallets to¹ are jointed.
These pallets work into two ratchet wheels x¹ secured on the ends of
the screws y. The screws y¹ pass through d. Each time therefore t
strikes u¹, the parts u², u³, v₁, and w¹, are moved, and the ratchet
wheels and screws y¹ caused to make a partial revolution of length
sufficient to bring the tool into position for the formation of a new cut;
2 is a spring to return the lateral traversing mechanism back into its
place. By duplicating certain parts of the lateral feed mechanism it
will be obvious the operating tool could be made to cut a groove every
single instead of every double stroke.
In practice with a machine of this construction I prefer to dress the
stone in the manner shewn by the dotted lines between X, X, before
moving the frame. The object of this is to reduce the length of that
part of the machine projecting beyond the skirt of the stone. It will
be obvious, however, the size of the frame can be varied. I may here
mention that instead of placing the top end of the tool to rotate
against a rigid thrust an elastic one may be used, such as a spring or
air cushion; but where the millstones are built up of stones of different
qualities I prefer to weight the tool f¹, and to provide a stop so

page_text: that it cannot fall downwards into any of the small cavities in the
stone.
Having now described the nature of my said Invention, and par-
ticularized the same so that others acquainted with the manufacture
and use of apparatus for dressing millstones will be enabled to make
and employ my improvements, I would have it understood that I do
not confine myself to the use of the rotating and travelling tool only
in the particular machines described, as such tools can be advantageously
used in other machines; what I claim is,
First. The employment of a rotating and travelling tool or drill tipped
with diamond or other suitable hard stone or substance for the purpose
of dressing millstones.
Second. The disposition and combination substantially as herein
described and illustrated on Sheet A of the Drawings of the mechanism
or parts for supporting, moving, and rotating a tool to act on and dress
millstones.
Third. The disposition and combination, substantially as herein
described and illustrated on Sheet B of the Drawings of the mechanism
or parts for supporting, moving, and rotating a tool to act on and dress
millstones.
In witness whereof, I, the said John Thomson King, have here-
unto set my hand and seal, this Twenty-fourth day of September,
in the year of our Lord One thousand eight hundred and sixty-
eight.
In the presence of
ROBERT MOSS.
JOHN THOMSON KING. (L.S.)