IMPROVEMENTS IN APPARATUS FOR CUTTING OR DRESSING MILLSTONES
Year: 1868

page_text: LETTERS PATENT to John Hine, of Cockermouth, in the County
of Cumberland, Miller, for the Invention of "IMPROVEMENTS IN
APPARATUS FOR CUTTING OR DRESSING MILLSTONES."
Sealed the 30th April 1869, and dated the 12th December 1868.
PROVISIONAL SPECIFICATION left by the said John Hine at the
Office of the Commissioners of Patents, with his Petition, on the
12th December 1868.
I, JOHN HINE, of Cockermouth, in the County of Cumberland,
Miller, do hereby declare the nature of the said Invention for "Iм-
PROVEMENTS IN APPARATUS FOR CUTTING OR DRESSING MILLSTONES," to be as
follows:-
My Invention relates to improvements in apparatus for facilitating
the cutting or dressing of millstones by means of diamonds or other hard
stones or cutters.
One arrangement of apparatus consists of a rectangular frame having
a longitudinal opening or slot in which works the block containing the
diamond or other cutter; this frame is firmly attached by means of a
nut working in a slot at one end of said frame to a radial arm pivotted

page_text: at the centre of the millstone so as to turn freely. The attachment
between the arm and frame is adjusted by means of the nut and slot
above mentioned, so that lines may be cut tangentially to any circle
described from the centre of the stone. When a line has been cut by
traversing the cutting tool or block above mentioned by hand from one
end to the other of the opening in the frame said frame is advanced a
suitable distance for making a second cut by turning a thumbscrew in rear
and near the outer end of said frame working in a screw socket pivotted
to a bed plate resting on the stone on which the operator sits. In this
manner by turning the thumbscrew each time the cutting block traverses
the frame a number of similar and successive cuts will be produced
extending tangentially from any circle described from the centre of the
stone to the circumference according to the angle at which the radial
arm is fixed to the frame. When the thumbscrew has reached the end
of its course its motion is reversed, and the bed plate advanced to
proceed as before until the cutting or dressing of the stone is completed.
In order to facilitate the dressing by causing the cutting tool to bear
on the stone with a uniform force the latter is provided-with-a-projecting.
flange on either side at the lower part received in a recess in-the-under
surface of the frame, so that the cutting block which must be inserted
in the frame from below is kept close down on the surface of the stone
during the cutting operation. The diamond I set in a holder placed
vertically in the plane or block. and secured therein as desired by
suitable set screws; this holder in which the diamond is set consists
of a metal shank enlarged at one end in the shape of a truncated cone,
in the centre of the base of which the diamond is set at the point of
intersection of two cross cuts made through the cone and extending
about half way up the shank, the diamond being held between the four
segments of the cone. Round the latter is passed a collar which is
forced over it by a nut screwed on the shank so as to cause the diamond
to be securely gripped in its setting. The cutting and dressing will be
further facilitated by adjusting several diamonds or other cutting stones
in a line in the block in such manner that the depth of the cut
in the stone may be gradually increased by each cutter successively,
instead of being made the whole depth at once by a single cutter only
as hitherto.
Another arrangement of my Invention, by means of which greater
cutting power is obtained, consists of a bar resting on the stone and
having a central longitudinal slot; this bar is jointed at one end to a

page_text: radial arm pivoted at the centre of the millstone. This joint is provided
with a binding screw working in a slot by means of which the bar can be
fixed at any angle to the radial arm. A movable clamp is placed in
the central slot in the bar near the outer end, so as to bear against
the periphery of the stone and fix said bar firmly in position. A
horizontal hand lever works at one end on a movable fulcrum placed
in the slotted bar, which fulcrum is fixed at any point in said slot
by means of a suitable nut; this hand lever carries the cutting tool or
block in which one or more diamonds or other cutters are fixetl, said
block being placed in a frame at about mid length of the lever. The
cutter block is passed over the surface of the stone for producing one or
more cuts by partially rotating the lever on its fulcrum before mentioned
as being fixed at any point in the slot, each cut produced being of curved
form and forming an arc of a circle of which the lever fulcrum is the
centre. When one cut, or in case of more than one diamond being
employed when one set of cuts) has been matle, the cutting block is
advanced along the lever the desired distance for making another cut
or set of cuts by means of a hand screw mounted longitudinally in the
lever and working in the cutting block. When the cutting block has
been moved along the lever by the rotation of the hand screw for making
cach cut or set of cuts, and so caused to traverse the whole extent of the
frame in which it slides, the slotted bar is removed by unfixing the
clamp before mentioned and transferred to another position on the stone,
where it is again fixed by means of the clamp and the cutting effected
as before, and so on until the dressing of the stone is completed.
Instead of the slotted bar being made to dress a portion of the stone
and shifted in position from time to time as above described said bar
may be made self-acting so as to advance after each motion of the hand
lever the distance desired for making another cut or set of cuts until
the dressing of the stone is completed; this I effect in the following
manner: The clamp before mentioned is dispensed with, and the
slotted bar instead of being hinged at one end to a radial arm as before
described is pivoted directly to the centre of a circular disc or plate
fixed by bolts or otherwise to the eye or centre of the stone. A.fixed
part projecting from the under side of the slotted bar takes under the
edge of the fixed plate, which is bevilled so as to keep said slotted bar
close down to the surface of the stone; this plate is provided with
projecting pins fixed at equal distances around its circumference, with
which gears a worin screw mounted in bearings in the slotted arm; this

page_text: worm screw is provided with a ratchet wheel at one end which is
operated on by a pawl. A lever arm works loosely on the axis of the screw,
provided with a slot in which is mounted the end of a rod connected to
the hand lever, said rod also carrying the pawl above mentioned. In
this manner every time a cut or set of cuts is produced by the partial
rotation of the land lever on its fulcrum the pawl is caused to act on the
ratchet and rotate the same (together with the worm screw to which it
is fixed) one tooth. As the worm screw gears as before described
with the pins on the fixed plate the slotted bar will be advanced or
rotated on its pivot the distance desired for making another cut or
set of cuts, which, supposing one diamond only to be employed, instead
of forming a series of concentric curves as in the previous arrangement,
will or curves of equal radius described from different centres.
Another arrangement of apparatus by which straight cuts are pro-
duced consists of a rectangular frame which rests on the surface of the
stone and is fixed-in-any-position-thercon by means of a tightening screw
with which it is provided engaging-with-a-part-pivoted_at_the_centre of
the stone; one or more parts projecting from the under surface of said
frame at the outer edge also abut against the periphery of the stone.
A second open frame slides in the first or fixed frame in dovetail slides
or-grooves... This sliding frame is provided with slots at one side in one
or other of which a slotted guide bar may be fixed at a diagonal position
by means of suitable bolts passing through both the cutter block slides
in this slotted guide bar, it being rebated therein so as to bear with
equal pressure on the stone. The cutting block is also provided with a
projecting pin received in a longitudinal slot formed in a horizontal hand
lever pivoted at one end to the sliding frame. In this manner on the
hand lever being partially rotated on its fulcrum or pivot the cutting
block will be traversed from one end to the other of the slotted guide
bar. After a cut has thus been produced the sliding frame (and con-
sequently the guide bar and cutting block) is advanced in its guide in
the fixed frame the distance required for making another cut by means
the following self-acting arrangement. On the fulcruma of a hand
lever a spur wheel is loosely mounted, said wheel being further provided
with ratchet teeth acted on by a pawl mounted on the hand lever. The
tecth of this spur wheel gear with an inclined wheel placed at right
angles to the first, by which it is rotated and mounted on a screw shaft
carried at one end in a bearing on the sliding frame and at the other

page_text: in a screwed socket formed on the fixed frame. In this manner at
every movement of the lever in one direction the pawl will engage with
the ratchet and so rotate tho spur wheel and screw shaft, the rotation of
which in its socket will move the sliding frame in its guides for the
purpose above mentioned. When the sliding frame has traversed the
whole extent of the fixed frame the latter is transferred to another
position on the stone and fixed as before described.
The sliding cutting block or diamond holder is made in two parts and
jointed together, so that in its backward motion the diamond or other
cutter will slide over the surface of the stone without cutting the
same.
In the several arrangements last described in which a hand lever is
employed steam or other motive power may be substituted for manual
labour if desired.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John line in the Great Seal Patent Office on
the 12th June 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HINE, of Cockermouth, in the County of Cumberland, Miller, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twelfth day of December, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said John Hine, Her special
licence that I, the said John Hine, my executors, administrators, and
assigns, or such others as I, the said John Eline, my executors, adminis-
trators, 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 Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN APPARATUS
FOR CUTTING OR DRESSING MILLSTONES," upon the condition (amongst
others) that I, the said John Hine, my exccutors or administrators,

page_text: by an instrument in writing under my, or their, or one or their hands
and seals, should particularly 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 Hine, 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, reference being had to the three Sheets of
Drawings hereunto annexed, and to the letters, and figures marked
thereon (that is to say) :-
My Invention, which relates to improvements in apparatus for facili-
tating the cutting or dressing of millstones by means of diamonds or
other hard stones or cutters, is illustrated in the accompanying Drawings,
in which Figure 1 shows a plan, and Figure 2-an-end--view-of-an-
improved arrangement of apparatus as applied for cutting or dressing a
millstone, a portion only of the latter being shown. The apparatus
consists of a rectangular frame A, having a longitudinal opening or slot
in which works the block B containing the diamond or other cutter.
This frame A is firmly attached by means of a nut 6 (working in a
slot at one end of said frame) to a radial arm C pivotted at the
centre D of the millstone so as to turn freely, pivot D being fixed to
an adjustable plate D' fitting in the eye of the stone. The attachment
between the arm C and frame A is adjusted by means of the nut band
slot 6', so that lines. may be cut tangentially to any circle described from
the centre of the stone. When a line has been cut by traversing the cutting
tool or block B by hand from one end to the other of the opening in the
frame A said frame is advanced a suitable distance for making a second
cut, as shown in red lines, by turning a thumbscrew E. connected to and
placed in rear and near the outer end of said frame A, said thumbscrew
working in a screw socket E¹ pivotted to a bed plate Fresting on the
stone, on which plate F the operator sits. In this manner, by turning the
thumbscrew E each time the cutting. block B. traverses the frame A, a
number of similar and successive cuts will be produced extending from
the circumference of the stone tangentially to any circle described from
the centre of the stone, according to the angle at which the radial arm C

page_text: is fixed to the frame A. When the thumbscrew E has reached the
end of its course the motion is reversed, and the bed plate F advanced to
procced as before until the cutting or dressing of the stone is completed.
In order to facilitate the dressing by causing the cutting tool to bear
on the stone with a uniform force the cutter block B (which is of similar
form to that described in a former Patent granted to me, and dated
June 26th, 1868, No. 2050) is provided with a projecting flange B' on
either side at the lower part, as scen in Figure 2. These flanges B
are received in a recess in the under surface of the frame A as seen,
so that the cutting block B, which must be inserted in the frame A
from below, is kept close down on the surface of the stone during the
cutting operation.
Figure 8 is a transverse vertical section of the cutter block B, showing
the mode of mounting the diamond or other hard stone cutter therein.
a is the diamond, which I set in a holder & placed vertically in the plane
or block B, and secured therein by a suitable set screw or screws e.
This holder d is shown partly in section in the detached view, Figure 4,
which also shows a face view of the diamond. The diamond holder d
consists of a metal shank enlarged at the lower end in a conical form, as
seen in Figure 4. The diamond a is set in the centre of the base of this
cone at the point of intersection of two cross cuts f made through the
cone and extending about half way up the shank, the diamond being
held between the four segments of the cone, as seen.
On said cone is:
placed a collar g, which is forced over it by a nut h, screwed on the
shank as seen, so as to cause the diamond a to be securely gripped in
its setting. The position of the holder d in block B is adjusted by
means of a screw i provided with a suitable knob and mounted in
block B, in which it is retained by means of a screw working in a
circular groove formed round the upper part of the screw shank, as seen.
This screw i works in a screw hole in the holder d, so that on said
screw being turned in in the one direction or the other (set screw e
having been previously loosened) the diamond a may be adjusted in any
position desired, and again secured by tightening screw e..
By adjusting several diamonds or other cutting stones in a line in the
block, as shown in Figures 5 and 6, the cutting and dressing will be
further facilitated. The diamonds e¹, e, e³, are of increasing dimensions,
so that the cut will be first produced by cutter e¹, the depth of said cut
being gradually increased by cutters e² and successively until the

page_text: desired depth of cut is attained, instead of the cut being made the whole
depth at once by a single cutter only as hitherto.
Another arrangement of my Invention, by means of which greater
cutting power is obtained, is shown in plan in Figure 7 as applied to a
millstone. It consists of a bar G, resting on the stone and having a
central longitudinal slot. This bar G is jointed at one end to a radial
arm H pivotted at the centre of the millstone. This jointed bar G is
provided with a binding screw j working in a slot in the end of arm H,
by means of which the bar G can be fixed at any angle to the radial
arm H. A movable clamp k is placed in the central slot in bar G near
the outer end, so as to bear against the periphery of the stone and fix
said bar G firmly in position thereon. I, horizontal hand lever working
at one end on a movable fulcrum 2 placed in the slot of bar G, which
fulcrum is fixed at any point in said slot by means of a suitable nui.
This hand lever carries the cutting tool or block B, in which one or
_more_diamonds or other cutters are fitted, block B being placed in
a-frame-m,-scen-in-Figure 8, which is an end view of bar G. The
cutter block B is passed over the surface of the stone for producing one
or more cuts by partially rotating the lever I on its fulcrum before
mentioned as being fixed at any point on the slotted bar G, each cut
produced being of curved form, as shown in red lines, and forming an arc
of a circle of which the lever fulcrum is the centre. When one-cut-.(or
in case of more than one diamond being employed when one set of cuts)
has been made, the cutting block B is advanced along the lever I the
desired distance for making another set of cuts by means of a hand
screw n, mounted longitudinally in the lever and working in the cutting
block B. When cutting block B has been moved along lever I by the
rotation of the hand screw n for making each cut or sct of cuts, and so
caused to traverse the whole extent of frame m in which it slides, the
slotted bar G is removed by unfixing the clamp k before mentioned and
transferred to another position on the stone, where it is again fixed by
means of the clamp k and the cutting effected as before, and so on until
the dressing of the stone is completed. Instead of the slotted bar G
being shifted in position from time to time after each portion of the
stone has been dressed, as above described, said bar may be made self-
acting, so as to advance after each motion of the hand lever I the
distance desired for making another cut or set of cuts, until the dressing
of the stone is completed. This I effect by means of the arrangement
shown in plan in Figure 9, and in longitudinal section Figure 10. The

page_text: clamp k before mentioned is dispensed with, and the slotted bar G instead
of being hinged at one end to a radial arm H, as before described, is
pivotted directly to the centre of a circular disc or plate L fixed by bolts
or otherwise to the eye or centre of the stone. A fixed part M projecting
from the under side of the slotted bar G takes under the edge of the
fixed plate L, which is bevilled so as to keep said slotted bar G close
down to the surface of the stone, as seen in section Figure 10. This
plate L is provided with projecting pins L' fixed at equal distances
around its circumference, with which gears a worm screw N mounted in
bearings in the slotted arm G, as seen. This worm screw N is provided
with a ratchet wheel at one end, which is operated on by a pawl o. A
lever arm N' works loosely on the axis of the screw N, and is provided
with a slot in which is mounted the end of a rod p connected to the
hand lever I before referred to, said rod p also carrying the pawl o
above mentioned. The parts being arranged in this manner every time
a cut or set of cuts is produced by the partial rotation of the hand
lever I on its fulcrum l, the pawl is caused to act on the ratchet and
rotate the same (together with the worm screw N to which it is fixed)
one tooth. As the worm screw N gears as before described with the
pins L' on the fixed plate L the slotted bar G will thus be advanced or
rotated on its pivot at the centre of the stone the distance desired for
making another cut or set of cuts, which (supposing one diamond only
to be employed) instead of forming a series of concentric curves, as in
the previous arrangement, will form curves of equal radius described
from different centres.
Another arrangement of apparatus by which straight cuts are pro-
duced is shown in plan at Figure 11. It consists of a rectangular
frame P which rests on the surface of the stone, and is fixed in any
position thereon by means of a tightening screw P¹ with which it is
provided engaging with a part På pivotted at the centre of the stone.
One or more parts projecting from the under surface of said frame at the
outer edge also abut against the periphery of the stone. A second open
frame Q slides in the first or fixed frame P in dovetail slides or grooves,
as seen in Figure 12, which is a section on line 1, 2, Figure 11; this
sliding frame Q is provided with slots rat one side in one or other of
which a slotted guide bar A (somewhat similar to that described in
Figures 1 and 2) may be fixed in a diagonal position on frame Q by
means of suitable bolts passing through both. The cutter block B
slides in this slotted guide bar A, it being rebated therein so as to bear

page_text: with equal pressure on the stone.
The cutter block B is also provided
with a projecting pin 2 received in a longitudinal slot q' formed in a
horizontal hand lever I pivotted at one end R to the sliding frame Q.
In this manner on the hand lever I being partially rotated on its fulcrum
or pivot R the cutter block B will be traversed from one end to the
other of the slotted guide bar A. After a cut has thus been produced
the sliding frame Q (and consequently the guide bar A and cutter
block B) is advanced in its guides in the fixed frame D the distance
required for making another cut by means of the following self-acting
arrangement-On the fulcrum R of hand lever I a spur wheel is
loosely mounted, said wheel being further provided with ratchet teeth s
acted on by a pawl s¹ mounted on the hand lever I, as shown in
detail in Figure 14. The teeth of this spur wheel gear with an inclined
toothed wheel placed at right angles to the first by which it is rotated,
said wheel being mounted on a screw shaft S carried at one end in a
bearing on the sliding_frame_Q_ and at the other in a screwed socket
-formed-on-the-fixed-frame-P.--In-this-manner-at-every-movement-of-the-
lever I in one direction the pawl &, seen in Figure 14, will engage
with the ratchet, and so rotate the spur wheel and screw shaft S, the
rotation of which in its socket will move the sliding frame Q in its
guides for the purpose above mentioned. When the sliding frame Q
has traversed the whole extent of the fixed frame P the latter is trans-
ferred to another position on the stone, and again fixed as before
described.
The sliding cutter block or diamond holder B is made in two parts
jointed together at T, as seen in Figure 13, which is a detached view of
the block, so that in its backward motion the diamond or other cutter a
will slide over the surface of the stone without cutting the same.
In the several arrangements of apparatus last described in which a
hand lever I is employed steam or other motive power may be substituted
for manual labor if desired for operating the same.
Having described the nature of my Invention, and the manner of
performing the same, I declare that what I claim as my Invention
to be protected by the herein-before in part recited Letters Patent
is,―
1st. I claim the apparatus shown in Figures 1 and 2 for cutting
tangential lines on the millstone arranged and operated substantially
in the manner shown and described.

page_text: 2ndly. I claim the mode of mounting the cutters described and
illustrated in Figures 3 and 4 of the Drawings.
3rdly. I claim producing the cut by gradually deepening the same
by means of several cutters arranged in the manner described and shown
in Figures 5 and 6 of the Drawings.
4thly. I claim the apparatus shown in Figures 7 and 8, by means of
which curved lines or cuts are produced, together with the self-acting
modification of the same shown in Figures 9 and 10, all arranged and
operating substantially in the manner shown and described.
5thly. I claim the apparatus shown in Figures 11, 12, 13, and 14
arranged and operated substantially in the manner shown and
described.
In witness whereof, I, the said John Hine, have hereunto set my
hand and seal, this Tenth day of June, in the year of our Lord
One thousand eight hundred and sixty-nine.