IMPROVEMENTS IN CUTTING AND DRESSING MILLSTONES AND OTHER HARD SUBSTANCES OR SURFACES, AND IN THE MACHINERY OR AP- PARATUS AND MEANS EMPLOYED THEREFOR.
Year: 1877

page_text: LETTERS PATENT to Robert Lees and James Anderson, both of Glasgow, in
the County of Lanark, North Britain, Millwrights and Engineers, for the
Invention of "IMPROVEMENTS IN CUTTING AND DRESSING MILLSTONES AND
OTHER HARD SUBSTANCES OR SURFACES, AND IN THE MACHINERY OR AP-
PARATUS AND MEANS EMPLOYED THEREFOR.' A communication from abroad
by Ambroise Millot, of Zurich, Switzerland.
"
Sealed the 8th September 1877, and dated the 21st March 1877.
PROVISIONAL SPECIFICATION left by the said Robert Lecs and James
Anderson at the Office of the Commissioners of Patents on the 21st March
1877.
ROBERT LEES and JAMES ANDERSON, both of Glasgow, in the County of Lanark,
North Britain, Millwrights and Engineers. "IMPROVEMENTS IN CUTTING AND
DRESSING MILLSTONES AND OTHER HARD SUBSTANCES OR SURFACES, AND IN THE
MACHINERY OR APPARATUS AND MEANS EMPLOYED THEREFOR." A communica-
tion from abroad by Ambroise Millot, of Zurich, Switzerland.
Our said Invention relates to the cutting and dressing of millstones and other
hard surfaces by a special new or improved construction or arrangement of that
class of machine known as the "diamond millstone dressing machine," which has
heretofore required constant attendance, having many of its parts or motions actu-
ated by the hand; and the object of the present improvements is to render such
machinery completely portable or self contained, and automatic or self acting in all
its motions, so that when once adjusted and started it may be left to dress round
the whole stone, without fear of derangement, thus doing much more work in a
given time, and rendering the constant services of an attendant unnecessary,
and effecting considerable economy in millstone dressing.
And the nature and novelty of the Invention or improvements consist in carrying
the whole dressing mechanism on a vertical, hollow, central column or frame, fitted
to a short hollow stem by a socket and universal joint, or "jimble" centres at
right angles to each other, the centre stem being either fixed on the top of the
spindle of the millstone, or secured by a flange to a block of wood or other

page_text: equivalent in the eye of the millstone, the lower boss or outer part of the column frame
having secured to it three nearly radial arms, a little above the upper surface of the
stone to be dressed, with movable steadying discs or flanges resting near the outer
edge thereof. One of these arms carries and has secured to it a nearly radial V
slide, on which the traversing carriage slides, and is reciprocated to and fro, having
fulcrumed to its lower edge the light horizontal oscillating frame which carries the
revolving spindle of the diamond holder, and held up by a spiral or other spring,
and pressed down by regulating pinching screws to give the desired depth of cut of
the diamond into the upper surface of the millstone. The first-motion and driving
shaft is carried in footstep and journal bearings in the centre column or frame, with
the upper end projecting sufficiently above to carry the driving and transmitting
cord or band pulleys, the upper smaller one preferably having one, two, or more V
conical grooves for giving different speeds, running loose on the spindle, and fitted
above with a central ball screw for engaging and disengaging this pulley to its
spindle or transmitting boss by friction, the lower larger pulley being secured by
its boss to the spindle having an endless cord passed round it, and led over two
guide pulleys, carried at the outer end of a sliding bar, carried on a radial bracket
secured to the top of the column frame over the slide carriage of the diamond
spindle, thence down to a small pulley, round which the free loop of the cord passes
to drive it at a high speed.
The diamond or other hard stones used for cutting and dressing in this machine
are mounted in an improved manner in a new or improved construction of diamond-
holding case or tool, which consists of a small cylinder, formed with a deep hollow
parallel screw at the head or back end, tightly fitted with a corresponding gripping
screw pin or stem, with head outside for screwing it up with a screwdriver or other
equivalent, both the case and pin or plug being preferably made of steel. The
other end of the case below the end of the screw plug is bored with a short conical
aperture, smallest at the outer end and widest within, and fitted with a corre-
spondingly shaped truncated conical brass bush, with a small conical or hollow recess
in its centre, also widest within, into which the diamond is set or fitted with gravers
or sharp steel tools, until the cutting point of the diamond projects a thirty-second
part of an inch or so beyond the outer end of the bush and its holding case, which
are both rounded and flush with each other at the end, so that the diamond only
projects to touch the work, the bush holding and supporting it down to near the
cutting point.
The inner end of the diamond is also left projecting a little beyond its holding
bush, and a small disc or thin plug of copper or other tough metal or material, into
which the inner projecting part of the diamond could bed itself, is placed between
it and the lower pressing end of the screw pin or plug, which when screwed up by
holding its outer case in a vice, compresses the soft washer down over the inner
projecting part of the diamond which is thus firmly embedded into the washer and
held between this and its holding bush, into which it may be more perfectly
embedded by solder, when desired.
This improved diamond holder or tool is fixed in a transverse, nearly round, hole
in the centre cylindrical part of its revolving spindle, and held between a slightly
V shaped slot on the one side, and two gripping prongs sliding in side slots at the
other end; these prongs being formed on the one side of the driving-cord pulley, on
the screw stem end of the spindle, with a tightening-up nut behind it, beyond
which the conical running centre projects, formed on the stem at this end, but pre-
ferably formed by an inserted removable centre fitted in the other end, which is
squared to hold by while screwing up the gripping nut behind its driving-cord
pulley at the other end: The said tightening-up nut and square at the opposite ends
of this improved driving spindle are formed with internal hollow annular grooves to
contain oil or other lubricant all round the large shoulder ends of its conical centres,
but contracted at the outer edge to fit and admit the inner ends of the hollow
conical bearing carrying centres, made in the form of short cylindrical stud centres,
fitted and fixed by pinching screws from the outside, within eyes or arms projecting

page_text: out from the duplex armed oscillating frame, carried on a fulcrum joint and pin at
the lower central part of the radial traversing carriage.
As this diamond-tool driving spindle revolves at a very high speed, the self-
lubrication of its running and bearing centres for a number of hours without
attention is of the utmost importance in this improved automatic machine, and to
effect. this, the outer end of each fixed centre is fitted with a close hinge-topped oil
cup, with wick tube running down the centre to a groove in the outer circumference
of the centre, with small radial holes leading to a larger axial hole or chamber in
the axial centre, carried forward to enter the conical bearing by a small hole, which
admits a small constant supply of oil to the bearing, which works out to the larger
bearing and close oil-containing groove part before mentioned; in the ends of the
running spindle, screw pins and washers are fitted at the ends of these centres for
keeping on the oil cups, the removal of which onables tlie holes or chambers up the
centre to be cleaned when required, the whole being found most effectual in
keeping the bearing rivets lubricated without attention for long periods.
The radial traversing carriage carrying this oscillating frame and diamond spindle
is actuated by the jointed end of a connecting rod, which is plain and parallel at
the other end, so as to be passed through and fixed in the centre of a swivelling
joint pin, at any desired position, by a pinching screw or other equivalent in the
lower end of its actuating pendent lever, fulcrumed on a strong stud in the upper
arın before mentioned, carrying the guide pulleys of the diamond-spindle driving
cord at the centre and face of its actuating disc, with radial slot and shifting crank
pin, which works through a sliding bush within a slot in the lever, the disc turning
on the same axis as its actuating worm or screw wheel, all carried on a bracket
projecting from the column frame through a slot in which the wheel works, so as
to gear into its actuating screw or worin, fixed on the lower end of the first motion
spindle working within the column, thus reciprocating the tool carriage to and fro
radially on its sliding guides, automatically at a slow regular speed from the first
motion shaft, the shifting of the crank pin in the revolving disc giving any
required length of stroke, the length of the connecting rod being adjusted
accordingly by its fixing pin in the joint at the lower free end of the actuating
lever.
The forward feeding motion of the whole frame and diamond tool revolving and
reciprocating mechanism round the stone on its lower socket, universal joint, and
steadying tripod arins, for cach new radial cut inwards and outwards of the
diamond, is given at each end of the traverse of the slide carriage by stud rollers
fixed on the back of the shifting crank pin and disc, nearly at right angles thereto,
to strike and. move a lever projecting up from one end of a counter or top feod
shaft carried in bearings on the upper side of the eye of the steadying arms, and
which by a weighted hand lever on the other end of the spindle, and a pendent
connecting rod, gives motion to the ratchet pall lever, so as to turn the ratchet
wheel with which it gears, fixed on the outer end of a screw spindle carried in
bearings in a swivelling hinged bracket jointed to the front of the outer boss of the
three-armed steadying frame, so as, by a small handle to be raised and lowered, to
put the screw out of or into gear with a large stationary screw spur wheel fixed
on the non-revolving part of the socket carrying the whole frame and just
below it.
A slot and holes, with retaining springs in the weighted feeding lever of the
ratchet motion, allow the pin at the upper end of the connecting rod to be shifted
to give a turn of one, two, or more teeth to the ratchet wheel, at each action every
time a tappet pin roller in the crauk disc comes round, and so turn the whole frame
and diamond cutter to the required extent for each new cut and traverse of the
diamond, and when it is only wished to cut in the one direction, inwards or out-
wards, one tappet roller only is used in the back of the disc, thus giving a perfect
automatic feeding action continuously all round the millstone.
The shifting of the bar and pulleys for compensating for the necessary shortening
and lengthening of the driving cord, during the traverse of the carriage and diamond

page_text: spindle frame, is effected by a cord attached at its inner end brought forward under
its guiding pulley over a pulley at the outer end of its carrying bracket, having a
weight attached thereto which presses out the compensating pulleys with the
regular tensional pressure due to that weight, sufficient to drive the spindle of the.
diamond, and yet not strain the cord or gut string.
For dressing the upper outer cutting surface of the stone truly flat, with the
usual sharp or "cracking" lines, the slide of the traversing carriage is fixed exactly
parallel to the surface, and the carrying frame of the diamond spindle is set to
project outwards, and automatically traversed to and fro and fed forward circum-
ferentially to give a fresh cut at every traverse, or only on the inner or outer
traverse, as desired, all as herein-before described; but for dressing and reducing
the inner or heart part of the surface of the stone at a slight angle towards the
centre for the feeding in of the grain, the inner end of the slide is lowered to the
angle desired by its fixing bolts and slotted holes for that purpose, and the oscil-
lating carriage, carrying the diamond spindle with its holding spring, is reversed on
its fulcrum joint so as to project inwards, and fitted with a pinching screw on that
side of its traversing carriage for regulating the depth of cutting action, all so that
the diamond can cut at any desired surface angle right into the eye of the stone.
The radial arm carrying the slide of the diamond frame and spindle is set parallel
to the radial cutting line of the diamond and not truly radial as the other arms
of the steadying frame are, so that the sharpening or cracking lines are cut truly
radial all round the stone; but when it is desired to cut the lines at any angle to
thic radial line, as along the landings parallel to the grooves, this might be done by
fixing the dovetailed or V slide of the carriage to its carrying arm at the angle
desired.
Although in the foregoing description the cutting and dressing of the surface
of the stones has been described as effected by a revolving diamond, this being
generally found preferable, it will be obvious that the same arrangement of auto-
matic mechanism may be used for working a non-revolving diamond in a fixed
holder in its oscillating frame attached to the reciprocating carriage, and although
the machine has been described as applied to dressing the surface of millstones, it
is equally applicable for dressing the flat surfaces of other stones, or the circum-
ferential surfaces of conical grinding or other stones, or of parallel grinding or other
rollers whether inade of stone, steel, porcelain, or other hard material, in which case
the stone or roller might be turned or fed round at cach cut with ratchet mechanism,
substantially as described for the feeding round of the frame and traversing
carriage.
The essential improvements or features of novelty constituting this Invention,
are,-
First. The carrying of the whole working parts of the machine on a single
portable revolving frame, preferably on a universal joint and stem at the bottom.
Second. The carrying of the first motion shaft within the axial column of the
frame, with the driving and transmitting cord or band pulleys on its upper end,
with engaging and disengaging friction clutch.
Third. The radial reciprocation of the diamond traversing carriage automatically
by a reciprocating lever through a disc and screw wheel, actuated by a screw in
the central first motion shaft.
Fourth. The automatic feeding or turning of the whole frame and radial slides
at each single or double traverse of the carriage by tappets in the crank disc
actuating the ratchet pawl and screw feeding mechanism, substantially as described,
for causing the diamond to cut either on the outward or inward traverse of its
carriage, or both, so that the whole surface of the stone may be continuously dressed
without stopping the machine.
Fifth. The carrying of the compensating guide pulleys of the endless cord for
driving the diamond revolving spindle on a reciprocating horizontal bar, moved by
a cord and weight.

page_text: Sixth. The new mode of securing the diamonds in the ends of hollow cylinders
with screw plugs, to be screwed radially in their driving or revolving spindles.
Seventh. The improved mode of constructing this revolving spindle for the
gripping of the diamond holder radially, and the carrying of the same in improved
hollow lubricating centres, each fitted with oil cups for automatically lubricating
the same.
Eighth. The carrying of the diamond revolving spindle, as stated, in a reversible
frame jointed to the lower side of the radially traversing carriage.
Ninth. The general arrangement and combination of the parts as before set forth,
forming for the first time a diamond cutting machine for dressing millstones, solf-
contained, portable, and perfectly automatic in all its motions, its mathematical
accuracy of construction and action effecting great economy of motive power,
reduction in the wear of diamonds, the universal joint enabling the mechanism
to bend in any direction, permits the dressing and simultaneous levelling of uneven
surfaces, while the diamond shaft being shorter than those used heretofore there
is no vibration, and consequently the diamonds are less subject to split or get loose.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Lees and James Anderson in the Great Seal Patent Office on
the 21st September 1877.
ROBERT LEES and JAMES ANDERSON, both of Glasgow, in the County of Lanark,
North Britain, Millwrights and Engineers. "IMPROVEMENTS IN CUTTING AND
DRESSING MILLSTONES AND OTHER HARD SUBSTANCES OR SURFACES, AND IN THE
MACHINERY OR APPARATUS AND MEANS EMPLOYED THEREFOR." A communica-
tion from abroad by Ambroise Millot, of Zurich, Switzerland.
Our said Invention relates to the cutting and dressing of millstones, and other hard
surfaces by a special new or improved construction or arrangement of that class of
machine, and many of its parts, known as the "diamond millstone dressing machine,"
which as heretofore constructed always required constant attendance, having many
of its parts or motions actuated by the hand; and the object of the present improve-
ments is to render such machinery or machines completely portable or self-contained,
and automatic or self-acting in all its motions, so that when once crected, adjusted,
and started, it may be loft to dress round the whole stone without fear of derange-
ment, thus doing much more work in a given time, and rendering the constant
services of an attendant unnecessary, thereby effecting considerable economy in mill-
stone dressing.
And in order that the nature, novelty, and mode of performing our said Invention
may be properly understood, we now proceed to describe the several Figures on the
Sheet of Drawings which we have hereunto appended for the purpose of showing
the best modes and means we are at present aware of for carrying the same into
effect or practice, the reference letters and numerals indicating the same or like parts
in all the Figures where shown.
Figures 1, 2, and 3, are a side and end vertical elevation and plan respectively of
this new or improved diamond automatic portable stone cutting or dressing machine,
all complete, in accordance with and illustrative of the improvements of this
Invention, and shown as erected on and in the act of dressing or sharpening the
grinding face of the millstone.
Figures 4 and 5 are respectively a vertical elevation and plan of the lower
stationary central support secured to the stone to be dressed, showing the improved
universal joint connection on which the pillar frame (carrying the working machine)
traverses round the stone. While Figures 6 to 13 are various elevations of special
parts of the machine shown full size, detached, to show the improvements and details
of construction more clearly; and Figure 13A is a sectional elevation of the cutting
diamond holder or tool, for being fixed in the revolving spindle, and drawn to an

page_text: enlarged scale of twice the actual size to show the improved construction more
clearly.
Referring to these Figures 1, 2, and 3, the new or improved construction or general
arrangement of this machine and of the special improved parts thereof consists all
as follows:-The whole moving and dressing mechanism is carried on a vertical
hollow central column A, or frame a, a, a¹¹, fitted to revolve on the eye A¹, and a
hollow stem B, screwed or fixed by the flanges B₁ to wood in the eye of the mill-
stone Z, or other equivalent, through an arrangement of socket piece C, tightly fitted
to the stem B, with one set of jimble joints c, and loose universal joint ring D,
swivelling on these with the second set of jimbles d on it, set at right angles to the
former c, and on which the lower eye A', on which the column A, a, a', a¹¹, rotates
and oscillates by snugs A", all as a universal joint connection or socket piece A', B, D,
C, on which the portable column A, with its arms a, a, a", and mechanism turn
when "shipped" on to the stem B, B. The boss or lower part A' of the column
frame A, has secured to, or formed on it, three nearly radial arms a¹¹, all, and a¹, a
little above the upper surface of the stone Z to be dressed, with movable steadying
discs a¹¹¹, or flange a³, resting near the outer and thereof. One of these arms a
carries and has screwed to it at El a nearly radial V slide guide E, on which the
traversing slide carriage F is carried and reciprocated to and fro by the connecting
rod F, and bas fulcrumed by snugs at F its lower edge, the light horizontal
oscillating frame G, shown full size in side elevation and plan detached in Figures G
and 7, and which carries the revolving spindle I shown in full sized side view,
detached in Figure 8, of the diamond holder K, shown full size and in section in
Figures 13 and 13A; a spiral or other spring of holding up the frame G against
one of the set screws,, in the slide carriage F, which are screwed up or down
to regulate the desired depth of the cut of the diamond in the upper surface
of the millstone Z or other hard surface to be dressed. The first motion and
driving shaft L is carried in footstep and journal bearings L, L", in the centro
column A of the frame A, a, a, a, a", having the upper end L' projecting
sufficiently above, to carry the loose driving and fixed transmitting cord or band
pulleys and respectively, the upper small one, Z, preferably having one, two, or
more different sized V grooves or cone, for the cord z to drive the pulley and
spindle at different speeds. A central band ball with screw L is fitted above on
the top L' of the spindle L to screw down the loose hollow boss of the pulley
and engage or, vice versa, disengage a conical friction clutch on its lower end into
that in the boss of the lower larger pulley ', secured to the spindle L, having the
endless cord passed round it, and led over two guide pulleys M (carried at the
outer end of a sliding bar m) carried and reciprocated on a radial bracket M',
secured to the top of the column frame A, over the slide and carriage E, F, thence
down to a small pulley on the diamond spindle I, round which the free loop of the
cord passes, to drive the spindle at a high speed.
Referring to Figures 13 and 13A the diamond or other hard stone, used for
cutting and dressing in this machine, is mounted in an improved manner in a new
or improved construction of diamond holding case or tool K, which consists of a
small hollow cylinder formed with a deep hollow parallel screw in the head or back
end, tightly fitted with. a corresponding gripping or pinching screw pin K¹, with
slit head for screwing it up outside with a screwdriver or other equivalent, both the
case K and screw pin K' being preferably made of steel; the other end of the case
K, below the end of the screw plug K, is bored with a short conical aperture,
smallest at the outer end and widest within, which is fitted with a correspondingly
shaped truncated conical brass or other metal bush or seating k¹, with a small
conical or hollow recess in its centre, also widest within, into which the diamond
is fitted or set, with gravers or sharp steel tools, until the cutting point of the
diamond projects a thirty-second part of an inch or so beyond the outer end of the
bush and its holding case, which are both rounded and flush with each other at the
end, so that when fixed radially in the hole I' of its revolving spindle I, as seen in
Figures 7 and 8, the diamond only projects to touch the face of the stone, or work

page_text: to this greatest depth of cut required, the bush holding and supporting the diamond
down to near the cutting point.
The diamond may be secured to the bush ¹ by a rim of solder round it on the
inside, and left projecting a little beyond to have a small disc or thin plug of
copper (or other tough metal or inaterial) inserted over it, and into which tho
inner projecting part of the diamond could berl itself by the pressure on a second or
corresponding washer of iron, both placed between the diamond and the lower
pressing end of the screw pin K₁, which when screwed up by holding its outer
case K in a vice or other equivalent compresses the soft metal washer & down over
the inner projecting part of the diamond k, which is thus firmly embedded in this
washer, and held between it and its holding or setting bush as in a vice.
This improved diamond holder or tool K, K', is fixed in a transverse nearly round
hole I' in the centre cylindrical part of its revolving spindle I, and held between
a slightly shaped slot i on the one side, and two gripping prongs sliding in
side slots at the other side, these prongs being formed on the one side of the driving
cord pulley 73 fitted on the screw stem end of the spindle I, with a tightening up
nut I behind it, beyond which the conical running centre I projects, formed on
the stom at this end, but preferably formed with an inverted removable centro I*
fitted in the other end I³, which is squared to hold by while screwing up the griping
nut I behind its driving cord pulley at the other end, all as seen in the detached
view, Figures 8 and 11 respectively of the spindle I, pulley 1, and centre. The
said tightening-up square 13 and nut I, at the opposite ends of this improved
driving spindle I, are formed with internal hollow annular grooves, as seen dotted
in at I, Figure &, to contain oil or other lubricant all round the large shoulder ends
of its conical centres I¹¹, I³, but contracted at the outer edge to fit and adinit the
innor ends of the hollow conical bearing carrying centres made in the forin of short
cylindrical stud centres g, shown detached in Figure 10, fitted and fixed by pinching
screws g¹ from the outside, within eyes or arms G₁ projecting out from the duplex
armed oscillating frame G, carried by back arms on a fulcrum joint and pin G₁ on
shugs Fat the lower central part of the radial traversing carriage F.
As this diamond tool driving spindle I revolves at a high speed the self-lubrication
of its running and bearing centres I", 12, for a number of hours without attention is
of the utmost importance in this improved automatic machine, and to effect this the
outer end of each fixed centre g is fitted with a close jointed oil cup gl, with a cap
on top, and wick tube gå running down the centre to a groove gl in the outer
circuniference of the centre g, with small radial holes leading to a larger axial hole
or chamber g³ in the axial centre, carried forward to enter the conical Bearing by a
sinall hole, which admits a small constant supply of oil to the bearing, which works
out to the larger bearing surface and close oil-containing groove I, before mentioned,
in the end of the running spindle I and nut 1111, washers g' being screwed on the
ends of these centres for keeping on the oil cups ", the removal of which enables
the holes or chambers up the centre to be cleaned when required, the whole being
found most effectual in keeping the bearing centres I¹¹, I², lubricated for long periods
without attention.
The radial traversing carriage F, carrying this oscillating frame G, G¹, and diamond
spindle I is actuated by the jointed end of a connecting rod F, which is plain and
parallel at the other end, so as to be passed through and fixed in the centre of a
swivelling joint pin N¹ at any desired position by a pinching screw or other equiva-
leht in the lower end of its actuating pendent lever N, fulcrumed on a strong stud
N" at the inner part of the upper arm M¹, before inentioned, over the centre and
face of its actuating disc O, with radial slot and shifting crank pin O¹, which
works through a sliding bush within a slot in the lever N, the disc turning on the
same axis O as its actuating worm or screw wheel P, all carried on a bracket A*
projecting from the lower part of the column A through a slot in which the wheel P
works, so as to gear into its actuating screw or worm P¹ fixed on the lower end of
the first motion spindle L working within the column, thus reciprocating the tool
carriage F to and fro radially on its slide guides E automatically at a slow regular

page_text: speed from the first-motion shaft L, the shifting of the crank pin O' in the revolving
dise O giving any required length of stroke, the length of the connecting rod Fi
being adjusted accordingly by its fixing pin N¹ in the joint at the lower free end of
the actuating lever N.
The forward feeding motion of the whole frame A, a, a¹, a¹¹, and diamond tool
revolving and reciprocating mechanisın round the stone on its lower eye A¹ of the
.socket B, C, D, universal joint C, D, and steadying tripod arms a, a, a¹¹, for cach
.new radial cut inwards and outwards of the diamond is given at each end of the
traverse of the slide carriage F, by stud rollers o fixed on the back of the crank
pin disc O, nearly at right angles to the crank pin O¹, to strike and move a lever pl
projecting up from one end of a counter or top feed spindle p, carried in bearings on
the upper side of the eye a of the steadying arms a, a¹, a¹¹, and which, by a weighted
hand lever on the other end of this spindle and a pendent connecting rod 22³,
gives motion to the ratchet pawl lever ql, so as to turn the ratchet wheel q¹¹¹, with
which it gears, fixed on the outer end of a screw spindle q, carried in eccentric..
bearings of a swivelling bracket q², jointed at g³ to the front of the outer boss a of
the three-armed steadying frame, so as by a small handle to be raised and lowered,
to put the screw of the spindle y out of or into gear with a large stationary screw
spur wheel q', fixed on the lower non-revolving socket A¹
り
A slot and holes are formed in the weighted feeding lever 21 of the ratchet
motion with a retaining spring, allow the pin at the upper end of the connecting
rod p² to be shifted in either of these holes, so as to give a turn of one, two, or more
teeth to the ratchet wheel q¹¹ of the screw spindle q at each action, every time a
tappet pin roller o in the crank disc O comes round, and so turn the whole
frame A, a, a, all, and diamond cutter to the required extent for each new cut
and traverse of the diamond; and when it is only wished to cut in the one direction,
inwards or outwards, one tappet roller o only is used in the back of the disc O,
thus giving a perfect automatic feeding action continuously all round the mill-
stone Z.
The shifting of the bar m and pulleys AI for compensating for the necessary
shortening and lengthening of the driving cord 2 during the traverse of the carriage
and diamond spindle frame F is effected by a cord m' attached at the inner end of
the bar m, and brought forward under its guiding pulley m³ over a pulley m² at the
outer end of its carrying bracket A, having a weight m" attached thereto which
presses out the compensating pulleys ML with the regular tensional pressure due to
that weight, sufficient to drive the spindle I of the diamond holder K, and yet not
strain the cord or gut string 12."
.
For dressing the upper outer cutting surface of the stone Z truly flat, with the
usual sharp or "cracking" lines, the slide E of the traversing carringe F is fixed
exactly parallel to the surface, and the carrying frame G of the diamond spindle I.
is set to project outwards, and automatically traversed to and fro, and fed forward
circumferentially to give a fresh cut at every traverse, or only on the inner or outer
traverse, as desired, all as herein-before described. But for dressing and reducing
the inner or heart part Z' of the surface of the stone, at a slight angle towards the
centre for the feeding in of the grain, the inner end of the slide E is lowered to the
angle desired by its fixing bolts E¹ and slotted holes in the retaining brackets for
that purpose, and the oscillating carriage G carrying the diamond revolving spring I,
with its holding spring f, is reversed on its fulcrum joint G", so as to project
inwards, and fitted with a pinching screw f¹ on that side of its traversing
carriage F for regulating the depth of cutting action, all so that the diamond and
tool K,, can cut at any desired surface angle right into the eye of the stone.
The radial arm a³, carrying the slide E of the diamond frame F and spindle I, is
set parallel to the radial cutting line of the diamond, and not truly radial, as the
other arms a¹¹, al, of the steadying frames A, a, a, a¹¹, are, so that the sharpening
or cracking lines are cut truly radial all round the stone; but when it is desired to
cut the lines at any angle to the radial line, as along the landings Z" parallel to the

page_text: grooves, this might be done by fixing the dovetailed or V slide E of the carriage F
to its carrying arm a at the angle desired.
Although in the foregoing description the cutting and dressing of the surface of
tho stones has been described as effected by a revolving diamond, this being generally
found preferable, it will be obvious that the same arrangement of automatic
mechanism may be used for working a non-revolving diamond, in a fixed holder, in
its oscillating frame G attached to the reciprocating carriage F; and although the
machine has been described as applied to dressing the surface of millstones Z it is
equally applicable for dressing the flat surfaces of other stones, or the circumferential
surfaces of conical or parallel grinding, or other stones, or rollers made of stone, steel,
porcelain, or other hard material; in which case the stone or roller might be turned
or fed round at each cut with ratchet mechanism, substantially as described for the
feeding round of the frame and traversing carriage.
This general arrangement and combination of the parts, all as herein described,
forms for the first time a diamond cutting machine for dressing millstones, which is
self-contained, portable, and perfectly automatic in all its motions, being driven by
a single open or cross band z passed round the differential V pulley from a pulley
on any adjacent motive-power shaft; its mathematical accuracy of construction and
action affecting great economy of motive power and reduction in the wear of
diamonds. And the mounting of the frame to turn on a universal socket and stem
joint at the bottom, enabling this and the mechanism carried on it to bend slightly
in any direction, admits of the simultaneous dressing and levelling of uneven
surfaces, while by the shortness of the diamond driving spindle I, obtained by those
improvements, all vibration is avoided, and consequently the diamonds are less
subject to split or get loose.
Having now described the nature of our said Invention, and the manner of per-
forming the same, we have to state that we do not confine ourselves to the precise
details herein described or delineated, but what we consider novel and original, and
therefor claim as the Invention secured to us by the herein-before in part recited
Letters Patent is,―
First. The general arrangement and combination of the parts of a portable
automatic diamond stone dressing or cutting machine, all substantially as herein
described in reference to and shown in the accompanying Drawings, or any mere
modification thereof.
.
Second. The carrying of the whole working parts of the machine on a single
portable column frame A, a, a¹, all, revolving on a universal joint and stem at the
bottom, all substantially as herein described in reference to and shown in the
accompanying Drawings, or any mere modification thereof.
Third. The carrying of the first-motion shaft L within the axial column of the
frame with the driving and transmitting cord or band pulley on its upper end,
with engaging and disengaging fricton clutch, all substantially as herein described
in reference to and shown in the accompanying Drawings, or any mere modification
thereof.
Fourth. The mounting of the whole portable frame and working parts on a
universal joint stem and socket arrangement, substantially as herein described in
reference to and shown in the accompanying Drawings, or any more modification
thereof.
Fifth. The radial reciprocation of the diamond traversing carriage F' automatically
by a reciprocating lever N through a disc O and screw wheel P, actuated by a screw
P on the central first-motion shaft L, all substantially as herein described in
reference to and shown in the accompanying Drawings, or any mere modification
thereof.
Sixth. The automatic feeding or turning of the whole frame and radial slides at
each single or double traverse of the carriage by tappets o in the crank disc O
actuating the ratchet pawl and screw-feeding mechanism fitted at its lower end,
for causing the diamond to cut either on the outward or inward traverse of its
carriage, or both, so that the whole surface of the stone may be continuously dressed

page_text: without stopping the machine, all substantially as herein described in reference
to and shown in the accompanying Drawings, or any mere modification thereof.
Seventh. The carrying of the compensating guide pulleys M of the endless cord
(for driving the diamond revolving spindle I) on a reciprocating horizontal
bar m, moved by a cord and weight, all substantially as herein described in
reference to and shown in the accompanying Drawings, or any mere modification
thereof.
Eighth. The new or improved mode of securing the diamond in the ends of
hollow cylinders or holders K, with pinching screw and metal washers, to be
fixed radially in their driving or revolving spindles I, all substantially as herein
described in reference to and shown in the accompanying Drawings, or any mero
modification thereof.
Ninth. The improved mode of actuating the revolving spindle I for gripping the
diamond holder K radially, and the carrying of the same in improved hollow
lubricating centres g, each fitted with oil cups for automatically lubricating the
same, all substantially as herein described in reference to and shown in the
accompanying Drawings, or any mere modification thereof.
Tenth. The carrying of the diamond revolving spindle I in a reversible frame G,
jointed to the lower side of the radially traversing carriage F, all substantially as
herein described in reference to and shown in the accompanying Drawings, or any
mere modification thereof.
In witness whereof, we, the said Robert Lees and James Anderson, have
hereunto set our hands and scals, this Twentieth day of September, in
the year of our Lord One thousand eight hundred and seventy-seven.
Witness,
W. R. M. THOMSON,
Patent Agent,
Glasgow.
ROBERRT LEES.
(L.S.)
JAMES ANDERSON.
(L.S.)